19 January 2013 New Scientist

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LASER VISION Mysterious cure for blindness

WEEKLY 19 January 2013

Sacrificing

Einstein Why we must let go of a foundation of relativity

weird weather

News, ideas and innovation www.newscientist.com The best jobs in science

From fires to freezes, 2013 is already a year of extremes Johnny come lately

New design for the humble condom

inexplicable dna Genes that appear from nowhere

bUMPOLOGY What to really expect when you’re expecting

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Greenfinch.......................................... House sparrow................................... Long-tailed tit .................................... Magpie................................................ Robin .................................................. Starling ............................................... Woodpigeon....................................... Other species

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20–29 January 2011

BWDNG20221

Contents

Volume 217 No 2900

This issue online newscientist.com/issue/2900



News

6 UPFRONT Space station prepares to blow up. Climate change plan B. Americans wealthy but not healthy. Wind farm for Fukushima. US flu alarm unnecessary. Beijing’s pollution 8 THIS WEEK Laser hope for blindness. The largest structure in the universe. Wanted: new dark force of nature. A clock to redefine the kilogram 16 IN BRIEF Wolverine mouse. Social supergene. Start early for musical genius. Why trees can only grow so tall. “Straitjacket” drug halts herpes

10 CHINE NOUVELLE/SIPA/Rex

Extreme weather From Australia to Brazil to the US, is this the new normal?

On the cover

32

8 Laser vision Mysterious cure for blindness 10 Weird weather 2013 is already extreme 37 Johnny come lately Condoms redesigned 40 Inexplicable DNA Genes from nowhere 28 Bumpology What to expect when you’re expecting

Sacrificing Einstein Why we must let go of a foundation of relativity

Cover image Jerry Young/Getty

44

Aperture 24 Shock waves from a speeding star



Opinion

26 Bluster buster Reg Platt on cutting through false claims about wind power 27 One minute with… Lisa Randall Let’s ditch theories of everything, says the top physicist 28 Call off the pregnancy police Women need facts, not myths or unsought advice about their condition, says Linda Geddes 30 LETTERS Animated psyche. Astro-pology

Features

32 Sacrificing Einstein (see above left) 37 Johnny come lately Condoms get a long-overdue makeover 40 Inexplicable DNA The genes that come from nowhere 44 Where in the world...? (see left)

Guillaume Pazat/Kameraphoto/Picturetank

Mapping enters uncharted territory

Technology

19 Superconducting  wind turbines. Vanishing skyscrapers. Drive by vibration. Cybermussels. Depth sensors for all. Scaring birds



Features

Where in the world…?

News



CultureLab

48 Laugh and the world laughs… Botox may change lives in a very unexpected fashion 49 Radiant health What we need to know about radiation. PLUS: Cosmic clarity



Coming next week… Dark solar

How to tap the sun’s energy 24/7

Regulars

5 Editorial Get used to wild weather 30 ENIGMA 60 Feedback Fossil poo. Mega spam 61 The Last Word Meaning of freckles 50 Jobs & careers

The 10,000-year bender

Humans’ long love affair with alcohol

19 January 2013 | NewScientist | 3

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Extreme is the new normal The wild weather that greeted the new year is here to stay ALL eyes have been on Australia more common, and now it is. in recent weeks as a blistering What’s more, although single heatwave triggered huge events can rarely be confidently wildfires. The result has been a attributed to climate change, slew of amazing stories, including clusters probably can. a family escaping by jumping into Many expected that such the sea and meteorologists adding weather disasters would be what new colours to heat maps. finally spurs governments into But Australia’s fires are just action. Perhaps surprisingly, there the most dramatic of a cluster of are signs that this is happening. ongoing extreme weather events, A report by GLOBE International – including droughts in the US and “Australia’s fires are just Brazil and a lethal cold snap in the most dramatic of Asia (see page 10). a cluster of ongoing Lumping extreme weather extreme weather events” events under a single umbrella can be misleading. Al Gore got into trouble when his film An a collective of environmentally Inconvenient Truth stitched concerned parliamentarians, of together footage of numerous which Gore was a founder – says hurricanes and presented them that politicians are doing more to as “evidence” of climate change. combat climate change than they But in this case it seems there are given credit for (see page 6). It really is a bigger picture. Scientists is a reminder that the impotent have warned for years that United Nations negotiations are extreme weather would become not the only game in town.

But don’t expect too much. Even if we began seriously cutting emissions, it would make little difference in the short term. A new study on stopping the impacts of climate change shows that rapid emissions cuts now would have only a small effect by 2050. The big dividends only emerge around 2100 (Nature Climate Change, doi.org/j7g). This effectively means that emissions cuts cannot help us or our children. That is not an argument for giving up, but it doesn’t inspire confidence that emissions reductions will ever be made a priority. The spate of extreme weather, then, is a snapshot of the not-toodistant future. Soon, this will be the new normal. We call events like the Australian heatwave “extreme weather”, but within the next few decades they will simply be “weather”. n

Into uncharted territory WHEN Google Maps launched in 2005, the reaction in some quarters was puzzlement. Why was a search engine getting into cartography? The answer became apparent as it rapidly enhanced the service with navigation, Street View, local business listings and so on. Google doesn’t just want to catalogue the online world; it wants to know where everything is in the physical world, too. Eight years on, that goal looks within reach. Google and its competitors now offer maps of the depths of the oceans and the far side of the Moon. They help their users to navigate everywhere from side streets to shopping malls. And they have revolutionised the way we think about location – putting us, rather

than some culturally significant but geographically arbitrary prime meridian, at the centre of the map (see page 44). This innovation has made digital maps all but indispensable to millions of people. They provide an alternative view of the world: one that offers suggestions about directions and places. They are also becoming one of the primary tools for exploring the wealth of civic data now available about our surroundings, from crime statistics to traffic flows. When the maps turn out to be wrong, though, we feel betrayed: witness the rare bloody nose dealt to Apple when it recently unveiled a buggy iPhone map app. Such trust issues hint at bigger battles to come. Many of today’s

wondrous maps are powered by deep-pocketed companies, each claiming to offer the ultimate in verisimilitude. But many details of their construction are trade secrets. This matters because all maps have their quirks and biases. Consider the Mercator projection, breakthrough mapping of a different age: it helped make global exploration possible, but grossly distorts the land area of different countries. More than 80 years ago, the philosopher Alfred Korzybski observed that “the map is not the territory”. A representation of reality, no matter how faithful it may seem, is not the same thing as reality itself. We should be mindful of that distinction as digital mapping evolves. n 19 January 2013 | NewScientist | 5

nasa/bigelow Aerospace

UPFRONT

Space station pumped up NASA wants to blow up part of the International Space Station – and a Las Vegas firm is eager to help. The US space agency has signed a $17.8-million contract with Bigelow Aerospace of Nevada to build an inflatable crew habitat for the ISS. Due for launch in 2015, the Bigelow Expandable Activity Module, or BEAM, will let astronauts test the module for safety and comfort. BEAM will fly uninflated inside the trunk of a SpaceX Dragon capsule. Once docked and fully expanded, the module will be 4 metres long and 3 metres wide. For two years astronauts will monitor conditions inside, such as temperature and radiation levels. Bigelow hopes tests will prove that inflatable capsules are safe and reliable for space tourists and

commercial research, an idea almost as old as NASA itself. The space agency began investigating the concept in 1958. Space stations like this would be easier to launch and assemble than metal components, so would be cheaper. But research ended after a budget crunch in 2000, and Bigelow licensed the technology. The company has made progress, such as designs that resist punctures from space debris. BEAM’s skin is made from layers of Kevlar to protect occupants from high-speed impacts. “It’s a great example of how a commercial company can save the taxpayer money while still allowing the agency to move forward aggressively with innovative new technologies,” says Bigelow director Mike Gold.

Climate progress

efficiency, the report says, with newly industrialising countries like China, Mexico and South Korea at the forefront. Such national measures are not enough, of course – the World Bank recently concluded that the world is still heading for 4 ˚C of warming by 2100 – but they may help enable a global emissionscutting deal in time for the United Nation’s 2015 target date. “Only if national regulatory frameworks are in place will it be possible to reach an agreement in 2015,” says GLOBE secretary Adam Matthews. There is no Plan C.

–Ready, steady, blow…–

US health horror

“In nine categories of ill health, US citizens consistently came near the bottom of the table” ranging from infant mortality rates to the prevalence of sexually transmitted disease, US citizens consistently came at or near the bottom of the table. 6 | NewScientist | 19 January 2013

Ed Jones/AFP/Getty Images

WEALTHY it may be, but healthy it is not. The US population experiences poorer health at all stages of life than the populations of 16 other rich countries. Despite leading the world in pioneering anti-smoking laws, cancer screening and controlling high blood pressure, the US trails its richer “peer” countries in almost all other measures of health and longevity, says a US National Research Council report published last week. At 75 years, men in the US have the lowest life expectancy in the group, while women have a life expectancy of 81 years – higher only than Denmark. In nine categories of ill health

“I was stunned by how pervasive the disadvantages were across so many factors,” says Steve Woolf of Virginia Commonwealth University in Richmond, who chaired the report panel. Woolf and his colleagues say that the problem is less to do with faults in the US health system, and more to do with behaviours that put US citizens at greater risk. “They consume the most calories per person, have higher rates of drug abuse, are less likely to use seat belts, and are more likely to use firearms in acts of violence,” says Woolf.

IT MAY be climate change’s bestkept secret. While global talks flounder, national governments are passing legislation to curb greenhouse gas emissions – a Plan B for fighting climate change. This optimistic message is at the centre of a new analysis by the London School of Economics, published by GLOBE International, a group of environment-minded parliamentarians. Of 33 major economies, 32 have now passed legislation to either combat climate change or improve energy

Soot woes deepen BEIJING is choking – and its sootladen smog is far worse for the world than we thought. With the city’s smog hitting a record high over the weekend, hospital admissions are up. Some reports have put airborne soot at over 30 times the World Health Organization’s recommended limit. Now Tami Bond of the University of Illinois at Urbana–Beijing smog: nasty in so many ways– Champaign and colleagues have

For daily news stories, visit newscientist.com/news

Wind over nuclear

revised the effect that soot has on climate change. They say its warming effect is almost twice the Intergovernmental Panel on Climate Change’s estimates, making it the second biggest warmer after carbon dioxide (Journal of Geophysical Research: Atmospheres, DOI: 10.1002/ jgrd.50171). Unlike CO2, soot only stays in the air for a few days. So action to curb soot from coal fires, diesel exhausts and cooking stoves could be a quick fix, says Bond. It would save lives, too. Soot is estimated to kill 2 million people a year, mostly through indoor pollution from cooking stoves.

60 Seconds

tsunami shutdown of the nation’s nuclear reactors. Project manager Takeshi Ishihara of the University of Tokyo insists that the area’s seismic activity won’t be an issue for the turbines: “All extreme

IT’S goodbye nuclear, hello renewables as Japan prepares to build the world’s largest offshore wind farm this July. By 2020, the plan is to build a total of 143 wind turbines on “Seismic activity won’t be platforms 16 kilometres off the an issue for the turbines. coast of Fukushima, home to the All conditions have been stricken Daiichi nuclear reactor taken into consideration” that hit the headlines in March 2011 when it was damaged by an conditions have been taken into earthquake and tsunami. The project, which will generate consideration”. Another issue is the impact on the fishing industry 1 gigawatt of energy, is part of a plan to increase renewable energy but Ishihara says the farm will be a “marine pasture”, attracting fish. resources following the post-

It’s only flu – not Flu-maggedon

No to Death Star

andrew kelly/reuters

NO IDEA is too outlandish to DON’T panic! Alarm over flu has gripped parts of the US this week: ignore. That might be a good hospitals were overwhelmed with motto for the White House, which cases, drug and vaccine supplies ran has announced that the US won’t low, and Boston and New York state be building a version of the Death declared public health emergencies. Star, the planet-destroying space But the situation is not as severe as station in Star Wars. it may seem. The White House was replying In the northern hemisphere, the to a request that began last year annual flu season usually peaks on its We the People website, around February. Even though it took which allows anyone to set up a off in December this time, such an petition and vows to respond to early start is not unheard of, and the those that gain enough support. number of new cases is already The Death Star petition suggested starting to fall. Hospital admissions that the project would create jobs and deaths have not been and strengthen US defences. It got exceptional, either. And this winter’s more than 34,000 signatures. flu viruses are not a major worry as The response was a goodthey are almost unchanged from natured but firm “no”. Paul those behind last year’s mild Shawcross, chief of the White House budget office’s science and space branch, cited a lack of US support for blowing up planets, the project’s estimated cost – close to a quintillion dollars – and a fatal design flaw exposed by one Luke Skywalker (who destroys the fictional Death Star). In his response, Shawcross also tries to inspire, mentioning the International Space Station, the Mars Curiosity rover and the exoplanet-hunting Kepler telescope. “If you do pursue a career in a science, technology, engineering or math-related field, the Force will be with us!” he adds. –We can cope in the usual way–

season – although it is notoriously hard to predict how a season will play out, says Jake Dunning, an infectious disease specialist at Imperial College London. So why have hospitals struggled? One reason is that the number of cases rose twice as fast as last winter, and with budget cuts over the past four years there are no spare beds to absorb the surge, public health experts say. Jack Herrmann of the US National Association of County and City Health Officials fears that recent efforts to build capacity to deal with disasters have been rolled back to such an extent that hospitals can’t handle a moderately severe flu season – never mind a disaster.

Confession time? Lance Armstrong, seven-time winner of the Tour de France, is reported to have admitted to using performance-enhancing drugs in an interview with Oprah Winfrey, set to air on 17 January. By coming clean, Armstrong could see his lifetime professional cycling ban reduced.

Cancer prophylactic Healthy women with a family history of breast cancer may be offered drugs to reduce their chances of developing the disease. Guidelines issued by the UK’s National Institute for Health and Clinical Excellence propose offering “high risk” women tamoxifen and raloxifene for five years. This is the first time a preventative drug for cancer has been recommended in the UK.

Vostok life quest Is there life beneath Antarctic ice? We may soon find out. Russian scientists have pulled up the first core of ice from Lake Vostok – a subglacial lake hidden under 3.5 kilometres of ice – which they intend to analyse for microbes.

Web activist tribute Hundreds of researchers are flagging up open-access versions of their work on Twitter as a tribute to Aaron Swartz, the internet freedom activist who committed suicide on 11 January. Swartz, who helped develop RSS and Reddit, was facing hacking charges after accessing the network of the Massachusetts Institute of Technology and downloading nearly 5 million articles.

Boeing battery fire US air safety watchdog NTSB is investigating a lithium battery fire that broke out on an empty Boeing 787 aircraft in Boston on 7 January. The Federal Aviation Administration, which attached strict safety conditions to the use of lithium batteries in the airliner, has also begun a “comprehensive review” of the 787’s design and manufacture.

19 January 2013 | NewScientist | 7

A laser to keep blindness at bay A promising treatment is shaking up our understanding of a major cause of vision loss Michael Slezak

IMAGINE the horror of being told you are losing your sight and that nothing can be done to prevent it. This is the reality for millions of people with age-related macular degeneration (AMD). But a novel laser treatment technique gives hope that this leading cause of blindness in the West could one day be preventable. Unpublished results from a successful pilot trial which ended last year, described to New Scientist, have left researchers scratching their heads as to exactly how it works. The findings also challenge ideas about the basis of the disease. A larger, randomised placebo-controlled trial is now under way. It’s very early days but, if successful, the treatment could prevent vision loss in millions of people globally. AMD corrodes the macula, a part of the retina at the back of the eye with the highest density of photoreceptors. The disease leaves people with a gaping hole in the middle of their vision, making reading and recognising faces difficult or impossible. AMD affects about 1 in 15 people at some point in their lives, and has a strong genetic component. It is most common among older white women, affecting about 1 in 6 over the age of 80. There is no treatment for the most common form of the disease (dry AMD), but drugs that slow its progression are available for the rarer, more aggressive form (wet AMD). In most people, the condition starts with unusually large or numerous deposits of extra8 | NewScientist | 19 January 2013

Macular regeneration A build-up of cellular debris (drusen) in the macular area of the retina causes the common form of age-related macular degeneration

NORMAL MACULA Photoreceptor cells

Back of eye

DRY MACULAR DEGENERATION

Degenerating photoreceptors

Drusen build-up Retinal pigment epithelium Shining a laser onto the macula seems to rejuvenate the cells of the retinal pigment epithelium, somehow enabling the clearance of the drusen Ciliary body Retina

Sclera Cornea Iris

Optic nerve Vitreous MACULA LASER

Lens

BSIP/UIG Via Getty Images

THIS WEEK cellular debris called “drusen” littering the retina. Drusen, which consist of proteins and lipids, are supposed to be cleared away by the retinal pigment epithelium (RPE) cells that they accumulate beneath (see diagram). But as those cells age they become less effective at doing that. The exact cause of what happens next is not well understood. Either because of the extra drusen, or as a result of whatever is damaging the RPE cells in the first place, the RPE cells become starved of oxygen. As they die off, they stop providing energy to the photoreceptors, causing them to die too. This is a serious problem as the density of photoreceptors is highest in the macula, so any loss noticeably affects vision. As early as the 1970s, there was some indication that laser treatment cleared away the drusen, but this did not come with an improvement in sight. In some cases, trials were even halted for fear they were making things worse. This is unsurprising as the lasers used were high energy and made visible burns on the retina. But today’s more sophisticated, low-energy lasers offer more trouble,” says Guymer. “There’s subtle options. been no other intervention where In 2010, ophthalmologist you can improve the function of a Robyn Guymer at the University person’s retina.” of Melbourne’s Centre for Eye So why should lasering the Research Australia conducted a already embattled RPE improve pilot trial with 50 volunteers who things? One theory is that the cells were in the very early stages of the “Volunteers had one eye disease, with some build-up of treated, yet surprisingly, drusen. They each had treatment many of them found an in one eye with a specially improvement in both eyes” designed laser. After treatment, the majority of the participants saw benefits – are so tightly bound that they a reduction in the amount of never divide and regenerate, drusen, an improvement in their eventually becoming less effective sight, or both. In lab tests, some at removing drusen. If the laser participants were able to notice shot through that layer, killing small differences in the intensity some of the cells and breaking of light that they hadn’t been able up the tight bonds, it may have to before, indicating that the allowed new RPE cells to be retina had regained some of its created. The laser should be able function. “The sensitivity of the to do this because, rather than a retina improved in the spots that uniform beam, it is made up of were most at risk of running into thousands of little beam spikes

In this section n The rise of extreme weather, page 10 n Dark matter made puffy by dark force, page 14 n How to make a sky scraper disappear, page 20

Guymer stresses, “that’s just the working hypothesis.” Philip Rosenfeld at the Bascom Palmer Eye Institute in Miami, Florida, is excited by the results and says the immune explanation is plausible. “You can come up with a lot of explanations but the most likely is that something is being stimulated in the immune system that’s been transferred to the other eye,” he says. Because of the surprising effects found in the pilot study, Guymer will be treating just one eye in each of the 300 people she

“There’s been no other intervention that has improved the function of a person’s retina”

which turn its target into a pincushion. It kills a smattering of individual cells but leaves enough healthy cells in between to kickstart the regeneration of the RPE. This cannot be the whole story, though. When Guymer conducted the pilot study she treated only one of each volunteer’s eyes in order to use the other as a control. To her surprise, among those participants who saw a reduction in the drusen, most of them experienced the effect in both eyes. “It’s a little hard to explain how the other eye is affected by the [rejuvenation] mechanism,” says Guymer. It seems something else is triggering a response in both eyes. Guymer reckons the immune system might be responsible. To protect the eye from potentially damaging inflammation caused by an immune response, it

aims to recruit for the larger trial, and is expecting both to benefit. The results will be keenly anticipated. “Small functional changes are very difficult to measure with precision and to repeat,” says Emily Chew from the National Eye Institute in Bethesda, Maryland. “I’m waiting to see the next step, when patients are –Time to loosen the drusen?– randomised. If there are truly differences, that will be very usually sits outside the immune some of the RPE cells, it effectively exciting and interesting for sure.” system’s radar. Unfortunately, Although still a long way off, alerts the immune system to the this means that the drusen are presence of the drusen, triggering Guymer sees a future where the also “in an immune privileged new laser is used as a preventative a double-whammy clean-up of position”, says Guymer, hidden measure in people at high risk of the debris by both the immune by a tight layer of RPE cells. She system and the newly rejuvenated AMD, in a similar fashion to the thinks that when the laser kills way heart attacks are prevented RPE cells. “That’s not proven,” by treating blood pressure. “Ultimately, if your parents had Retinal cells busted? Grow new ones AMD, you’ll have a genetic test Another way to stop age-related to use induced pluripotent stem and if you’ve got the gene you’ll macular degeneration might be to (iPS) cells. These are made by have this laser and you won’t get grow yourself some new retinal taking a volunteer’s own cells and the disease. That’s where we pigment epithelium (RPE) cells. “rewinding” them to a stem cell state. would like to head. One lasering, Several groups around the world This enables the cells to turn into perhaps once a year, for those who have been using embryonic any kind of tissue, and since they are genetically at risk,” she says. stem cells to do just that – but come from a volunteer’s own body, If Guymer had her way, this with embryonic cells, there is a they are unlikely to be rejected. approach would be just the risk that your immune system will In the next 18 months, Takahashi start. She imagines a time when reject them. will embark on one of the world’s people at genetic risk simply To tackle this problem, Masayo first human trials of an iPS cell get vaccinated so their body Takahashi and colleagues from the treatment, turning participants’ recognises the drusen and clears it Riken Centre for Developmental skin cells into RPE cells before away. “We just need to trigger the Biology in Kobe, Japan, are planning injecting them into their eyes. immune system to do a better job cleaning up that debris.” n 19 January 2013 | NewScientist | 9

NEWS FOCUS / Extreme weather

WELCOME TO EARTH’S FUTURE

CHINE NOUVELLE/SIPA/Rex

The rise in extreme weather is a sign of things to come, find Michael Marshall and Sara Reardon

10 | NewScientist | 19 January 2013

US: The new dust bowl The US is experiencing one of its worst droughts in a century. About 60 per cent of the country is affected. In 2012, a quarter of the corn (maize) crop was lost. The drought is set to continue, and its impacts will be felt around the world. Last year was the hottest year on record

world’s corn and much of its grain. According to the US Department of Agriculture, the 2012 grain loss means global food prices will rise by 3 to 4 per cent in 2013, even if the drought abates. That’s unlikely to happen soon. The US National Oceanic and Atmospheric

in the US. News coverage of the resultant drought may have slowed, but the event is simply lying dormant through the winter. The US provides about half of the

Administration’s 2013 drought outlook predicts that conditions in the agricultural Midwest will continue or worsen until at least April. “There really isn’t anything on

Victor J. Blue/Bloomberg via Getty

THE year has just begun, yet it is already shaping up to be an unusual one. Millions of people in Australia, Brazil, China and the US are having a rough January as extreme weather events wreak havoc around the world. In the absence of natural climatic triggers like an El Niño event, such an accumulation of extremes is highly unusual, says Omar Baddour of the World Meteorological Organization in Geneva, Switzerland. Until further studies are carried out, it is impossible to rule out that some of the extremes are freak events. But they all coincide with regional increases in extreme weather linked to climate change. The US, for example, is in the grip of worsening drought. Last week, the US Global Change Research Program released a draft of the third National Climate Assessment. This shows that the country is seeing longer periods of excessively high temperatures, and in places more severe droughts due to the accumulation of greenhouse gases in the atmosphere. Global temperature records show that there is an 80 per cent chance that any new monthly heat record is caused by climate change (Climatic Change, doi.org/ j7h). That means events like the heatwave that has set Australia ablaze (see page 12) have become more likely because of long-term warming, says Dim Coumou of the Potsdam Institute for Climate Impact Research in Germany. The effect of climate change varies regionally, and if a new monthly record is set in Australia at the end of January, there is a 50 per cent chance that the current heatwave was triggered by global warming, he adds.

Drought is baking much of the US, but China has hit its lowest temperatures for 28 years

the horizon that’s showing an overall improvement to the drought situation,” says Brian Fuchs of the National Drought Mitigation Center in Lincoln, Nebraska. For states such as Kansas and Texas, which have been in drought since 2010, conditions are comparable to those of the 1950s and the 1930s Dust Bowl, Fuchs says. This month, the US Department of Agriculture declared 20 per cent of the agricultural US a natural disaster area.

Track global warming where you are: bit.ly/WarmingWorld

Much of Asia has been freezing in the

intense waves of cold, says Omar

past few months. Since the end of November, China has seen its coldest

Baddour of the World Meteorological Organization in Geneva, Switzerland.

temperatures in 28 years, according to

Paradoxically, there is growing

its meteorological administration. Sea

evidence that retreating Arctic sea ice,

ice in Bohai Bay, to the northeast of the country, has grown to the largest

which hit a record low in September, is to blame, which links the trend to

extent for 25 years. The cold conditions

greenhouse gas emissions.

have extended into western Russia, where temperatures have been 6 °C

Normally, winters in the northern hemisphere are dominated by westerly

below average, and northern India – where over 200 have died as a result. Even the Middle East has been hit, with Israel and neighbouring countries suffering snowstorms and floods. It is the fourth year in a row that the northern hemisphere has seen large,

winds, driven by the temperature gradient between the warm equator and the cold North Pole. But as the Arctic sea ice retreats, the polar ocean warms faster and the westerlies are weakened. This allows cold air to spill out of the Arctic, and into Eurasia.

BULENT KILIC/AFP/Getty

Asia: Record low and storms of snow

Heavy snow brought Istanbul to a halt this month

Brazil: drought threatens power

Eraldo Peres/ap

A bone to pick: drought-stricken Brazilian farmers campaign for financial assistance The north-east of Brazil is going through its worst drought in decades. It has dragged on for more than a year, according to the US National Oceanographic and Atmospheric Administration. The event offers a stark warning of the problems climate warming could cause for Brazil. Brazil relies on two power sources that are vulnerable to drought. In 2010, hydroelectricity met 29 per cent of the country’s energy needs, according to the US Energy Information Administration. And Brazil’s production of ethanol

biofuels more than doubled between 2001 and 2010 – although it fell almost 20 per cent in 2011. This makes Brazil’s energy supply sensitive to climate change, says André Frossard Pereira de Lucena of the Federal University of Rio de Janeiro. In 2008, his team looked at how the climate would affect these supplies by 2100. Ethanol, they found, was unlikely to be affected, but biodiesel was vulnerable. Hydroelectric power was worse off, as river flows were likely to shrink. The north-east of the country, already the poorest, is most prone to change (Energy Policy, doi.org/dp7t52). So far, no study has directly linked this drought to climate change. But the latest report of the Intergovernmental Panel on Climate Change predicted that rising emissions will make semi-arid regions, including the north-east of Brazil, increasingly susceptible to such events.

19 January 2013 | NewScientist | 11

Dan Himbrechts/Newspix/Rex

NEWS FOCUS / Extreme weather

How will Australia cope with more bush fires?

12 | NewScientist | 19 January 2013

Tinderbox: fire risk in parts of Australia is so high no homes should be built there

‘Impossible’ ‘Impossible’ weather weather forecast forecast

Temperature Temperature Both models and data show that climate change increases Both models and data show that climate change increases temperatures and their variability. This creates a more flattened temperatures and their variability. This creates a more flattened bell curve of likely temperatures. Events that were once incredibly bell curve of likely temperatures. Events that were once incredibly unlikely – in the tail end of the curve – become relatively normal. unlikely – in the tail end of the curve – become relatively normal. Events never seen before become the new extremes Events never seen before become the new extremes

SOURCE: SOURCE: IPCC, IPCC, HANSEN HANSEN 2012 2012

Unprecedented Unprecedentedheat heat

Extreme Extremeheat heat

How does a rise in global temperatures of approximately How does a rise in global temperatures of approximately 1°C – a seemingly small number - bring about an onslaught 1°C – a seemingly small number - bring about an onslaught of extreme weather events? of extreme weather events?

Extreme Extremecold cold

CLIMATE change is ramping up fire risk around the world. In Australia, home to some of the most fire-prone regions on Earth, the bush fires raging now could be a taster of what’s to come. Parts of the world where the fire risk is rising can learn from Australia’s experience, says John Handmer, director of the Centre for Risk and Community at RMIT University in Melbourne. A good place to start would be “uninhabitable zones” – places where the fire risk is so high no homes should be built. Such zones became a reality after “black Saturday” in 2009, when fires killed 173 people and destroyed over 2000 homes in the state of Victoria alone. A royal commission recommended a “retreat and resettlement” strategy for areas of “unacceptable fire risk”. Under a voluntary buy-back scheme, the state bought more than 100 properties destroyed in the fires, and new buildings in high-risk areas now require a special permit. Handmer says Australia should be mapped based on fire risk, and the government should buy up the spots

that are too dangerous for houses. North-facing ridges or gullies, where we know fires tend to funnel, should be considered out of bounds for housing development. Many of these areas have been developed in the absence of such policies, he warns. “They’re setting us up for the catastrophes of the future.” There is little doubt that climate change is already making fires more likely in Australia, says Andy Pitman of the University of New South Wales in

Probability Probabilityofof occurrence occurrence

Michael Slezak, Sydney

Sydney. Australians were warned that they faced the highest ever risk this year. A couple of wet years led to extra growth in forests and grasslands, then a record heatwave dried everything out, turning it into a tinderbox. The heatwave smashed records and Australia’s Bureau of Meteorology has called it “consistent” with climate change. The average temperature across the country reached 40.33 °C last week, beating a 1976 record of 40.17 °C. In 1973 the average maximum temperature sat above 39 °C for four days. Last week, it stayed that way for seven days. “We are absolutely annihilating records,” says Pitman. Such records are made more likely by rising greenhouse gas emissions (see graph, below). Additional factors that help fuel fires will also worsen as the climate continues to warm, says Pitman. Elevated carbon dioxide in the atmosphere will fertilise plants during moist periods, creating more fuel. Increased variability means wetter wet periods will boost plant growth, and be followed by drier dry spells – a perfect storm of conditions for fires to break out. So fires are more likely, and likely to be bigger, says Pitman. Predictions are sobering. A 2011 study of the south-east of the country used climate models to predict changes in the number of days with “very high” or “extreme” fire risk. It forecast an increase of 70 per cent by 2050. That would leave less time for safe controlled burning – a method used to reduce the amount of fuel available for bush fires – potentially making fires more severe. Another study, led by Pitman, found the national fire risk in January would increase by 25 per cent by 2050. By the end of the century it could double in some areas, including the New South Wales and Queenland coastlines, (Climatic Change doi.org/b46h7m). These studies don’t include detailed models of how vegetation will change and affect fires, but they are the best we have at such small scales, notes Ross Bradstock, director of the Centre for Environmental Risk Management of Bushfires at the University of Wollongong in New South Wales. “It’s getting a bit scary to be perfectly honest,” says Pitman. n

ESO/M. Kornmesser

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Largest structure defies smooth cosmic theory A COLUMN of galaxies 4 billion light years long has grabbed the accolade as the largest known structure in the universe. It also challenges Einstein’s idea that, on large scales, the cosmos looks the same in every direction. The hunt for cosmic giants focuses on quasars, brightly glowing cores found at the centre of some galaxies. These tend to clump together in large quasar groups (LQGs), in which each quasar is closer to another member of the group than those outside. “We look for quasars that have a certain separation from the next nearest quasar,” says Roger Clowes of the University of Central Lancashire in Preston, UK. In 1991, Clowes helped discover the previous record holder, containing 34 quasars and measuring 1 billion light years across.

Now his team has found an LQG four times as long using data from the Sloan Digital Sky Survey, the most comprehensive 3D map of the universe (Monthly Notices of the Royal Astronomical Society, doi.org/ j7d). Composed of 73 quasars and dubbed Huge-LQG, it not only steals the cosmic size crown, but threatens to defy the cosmological status quo. When Albert Einstein first applied his theory of general relativity to the universe as a whole, to make the calculations workable he was forced to assume that one large part looks much like any other. This became known as the cosmological principle, but a question remained: how large is a large part? Previous calculations gave a maximum value of 1 billion light years, the size of the 1991 LQG.

–Quasars: heart of the size hunt– But Huge-LQG smashes this limit. “There is structure on scales at which the universe is supposed to be boring,” says Subir Sarkar, a theorist at the University of Oxford who was not involved in the work. That could simply reflect a need to revise upwards the size limit on large structures, or, as Clowes suggests, it could undermine the cosmological principle. After all, other evidence,

including a controversial “dark flow” of galaxies that seem to move in the same direction, is also poking holes in the uniformity of the universe. However, the cosmological principle is so ingrained – and useful – that it may be hard to shake. “People are understandably reluctant to give up on the thing, because it will make cosmology too bloody complicated,” says Sarkar. Jacob Aron n

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THIS WEEK

Dark matter slowed by unknown force A MYSTERIOUS force acts only on dark matter. That’s the conclusion from observations of a huge galactic collision, and it hints that there could be a whole menagerie of particles and forces lurking at the edge of human perception. Dark matter is the invisible stuff that makes up 86 per cent of the mass in the universe. It famously refuses to interact with ordinary matter except via gravity, so theorists had assumed that its particles would be just as aloof with each other. Some of the best evidence for this comes from the Bullet cluster, the aftermath of a small galaxy cluster plunging through a larger one about 100 million years ago. Separated by hundreds of light years, the galaxies in the two clusters sailed right past each other and drifted apart. But the intergalactic gases collided and slowed down. The sluggish gas got dragged along as the clusters parted ways, and it pooled on their trailing ends. Mass maps of the Bullet cluster show that dark matter stayed with the galaxies and did not

Tick of matter may help define the kilogram IMAGINE weighing yourself with a watch. In theory, that’s now possible thanks to a clock with a tick that depends on the mass of a single atom. More practically, the clock could help efforts to redefine the kilogram in terms of fundamental constants. The most accurate clocks are atomic clocks, which measure how often electrons in an atom such as 14 | NewScientist | 19 January 2013

X-ray: NASA/CXC/UCDavis/W.Dawson et al; Optical: NASA/STScI/UCDavis/W.Dawson

Lisa Grossman

they found that its galaxies are separated from its dark matter (coloured blue in the picture below) by about 19,000 light years. Some dark matter was more in line with the hot, slow-moving gas (shown below in pink). “The galaxies outrun the dark matter. That’s what creates the offset,” says Dawson, who presented the work last week during a meeting of the American Astronomical Society in Long Beach, California. The scenario suggests that dark matter does slow down like gas and so must be interacting with itself via some force other than gravity. Dawson thinks the Bullet cluster doesn’t look the same because it is much younger and its dark matter

hasn’t had time to separate out. The new work could solve some outstanding mysteries in cosmology, Dawson says. If dark matter did not interact with itself, it should sink to the cores of star clusters and dwarf galaxies, but slow down with the gas, which observations show that it is more hints that dark matter wasn’t evenly distributed. If it interacts interacting with itself and was with itself through a dark force, affected by gravity alone. that might cause it to puff up But last year, William Dawson and spread outwards like a gas. of the University of California, Dawson thinks the result might Davis, and colleagues found a be a starting point for finding smash-up that told a different an entire zoo of dark forces and tale. Nicknamed the Musket particles, like a shadow version Ball cluster, this pair of clusters of the fundamental physics that collided about 700 million govern normal matter. years ago. When Dawson’s team “There could be a whole class analysed the concentration of of dark particles that don’t interact mass in the Musket Ball cluster, with normal matter but do interact with themselves,” agrees team member James Bullock of the University of California, Irvine. “Dark matter could be doing all sorts of interesting things, and we’d never know.” Still, two clusters are not a lot to go on. Dawson, Bullock and colleagues are following up with about 20 more galactic collisions to see if they also show any unusual behaviour. “Self-interacting dark matter is worth pursuing because we’re still very ignorant,” says Louis Strigari of Stanford University in California, who was not involved in the study. “We’re desperate to understand what dark matter is, –Musket Ball galaxies outrun dark matter– so any new window is welcome.” n

caesium jump between two energy levels. Roughly 9 billion of these transitions equal 1 second. But there is another way to count time using an atom. Quantum theory says that all matter exists as a wave, as well as a particle. This means each particle has a frequency, which can act as the tick of a clock. As the frequency depends on the atom’s mass, the clock could in principle be used to weigh things, but the frequency itself is too high to count. So instead a team led by Holger Müller at the University of California, Berkeley, split the wave of a caesium

atom in two, keeping one half stationary and the other moving. Einstein’s theory of special relativity means time passes slower for the moving wave, so when the two were re-combined, they were out of phase. Müller’s team were able to measure this phase difference, which, like the atomic frequency, also depends on the mass of the atom. The result was the tick of the

“Quantum theory means each particle has a frequency, which can act as the tick of a clock”

first mass clock (Science, doi.org/j7j). This new kind of clock might make an expected, more precise definition of the kilogram easier to use. The scientific standard for mass is currently defined by a lump of metal, but its mass is drifting so the plan is to replace this with a definition based on fundamental constants. A device is still needed to measure physical masses, though. The current favourite is called a watt balance, but this is limited to macroscopic objects. The new mass clock provides a way to measure microscopic masses, too. Jacob Aron n

Win a trip to the top of the world... and the bottom of the sea New Scientist has teamed up once again with the global energy company Statoil to offer one lucky winner and a guest the trip of a lifetime. You will sail around Svalbard in the Arctic Circle, take a helicopter ride to the Troll platform and visit the bottom of the North Sea.

To win this fabulous prize all you have to do is to tell us in no more than 100 words which energy technology you think will have the biggest impact on our lives in the near future, and why. That doesn’t just mean energy-generating technologies, but any device or process that could save energy or perhaps trigger a new, world-changing industry or behaviour.

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IN BRIEF Ghost in the cosmic fog machine

Think this leaf is big? Take a look at the ones over there TYPICALLY, the taller the tree, the smaller its leaves. The mathematical explanation for this phenomenon, it turns out, also sets a limit on how tall trees can grow. Kaare Jensen of Harvard University and Maciej Zwieniecki of the University of California, Davis, compared 1925 tree species, with leaves ranging from a few millimetres to over 1 metre long, and found that leaf size varied most in relatively short trees. Jensen thinks the explanation lies in the plant’s circulatory system. Sugars produced in leaves diffuse through a network of tube-shaped cells called the

phloem. Sugars accelerate as they move, so the bigger the leaves the faster they reach the rest of the plant. But the phloem in stems, branches and the trunk acts as a bottleneck. There comes a point when it becomes a waste of energy for leaves to grow any bigger. Tall trees hit this limit when their leaves are still small, because sugars have to move through so much trunk to get to the roots, creating a bigger bottleneck. Jensen’s equations describing the relationship show that as trees get taller, unusually large or small leaves both cease to be viable (Physical Review Letters, doi.org/ j6n). The range of leaf sizes narrows and at around 100 m tall, the upper limit matches the lower limit. Above that, it seems, trees can’t build a viable leaf. Which could explain why California’s tallest redwoods max out at 115.6 m.

Drug spoils herpes’s straitjacket escape AS ANYONE with recurrent cold sores knows, herpes is a master escape artist. But now a treatment that cuts off the virus’s means of escape could thwart its disappearing and reappearing act. When the virus infects cells, the body defends itself by wrapping up the viral genome to prevent the viral genes from being expressed. The virus hijacks the cell’s own enzymes to free itself. After the 16 | NewScientist | 19 January 2013

infection, the virus hides elsewhere in the body. Thomas Kristie at the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, and colleagues developed a drug that halts the virus’s escape by inhibiting the enzymes it uses to free itself (Science Translational Medicine, doi.org/j64). The team tested the drug on mice infected with the herpes that

causes cold sores. A month later, once the virus was dormant, neurons were cultured from the brain’s trigeminal ganglia, which harbours that type of herpes. The virus did not reactivate. The approach could “open up a new arena of antiviral drugs” that shut down herpes viruses at an early stage of infection, says Kristie. But the drug is a bit of “a sledgehammer”, says Robert White at Imperial College London, so side effects must be investigated.

GHOSTLY galaxies in the distant universe are almost certainly the culprits behind reionisation, a change in intergalactic gas that allows us to see across the cosmos. About 300,000 years after the big bang, the charged hydrogen that filled the universe became neutral and opaque, creating a cosmic fog that blotted out visible light for a billion years. Then some form of radiation broke up the hydrogen, reionising it and making it clear. One theory says the radiation came from galaxies, but Hubble’s deepest view of the universe shows that bright galaxies present during the reionisation era would not have been powerful enough. Now statistical analysis shows there should be many faint galaxies we can’t yet see – enough to do the job, Matthew Schenker of the California Institute of Technology said last week at an astronomy meeting in California.

Planet guts found on dead stars ZOMBIE stars covered in pollution can reveal the types of planets that existed when the stars were alive. A white dwarf is the dense core left behind when a sun-like star dies. Heavy elements should sink deep inside, leaving only hydrogen and helium in the star’s atmosphere. But about a quarter of all white dwarfs are polluted with elements such as iron and silicon. An analysis of 60 dirty dwarfs shows that heavy elements exist in similar ratios to what is inside Earth, says Michael Jura of the University of California, Los Angeles, who presented the work last week at an astronomy meeting in California. He thinks the stars are eating bits of planets and asteroids that were similar to objects in our solar system.

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Mikael Damkier/Alamy

GOOD news for pushy parents. If you want your child to excel musically, you now have better justification for starting their lessons early. New evidence comes from brain scans of 36 highly skilled musicians, split equally between those who started lessons before and after the age of 7, but who had done a similar amount of training and practice. MRI scans revealed that the white matter in the corpus callosum – the brain region that links the two hemispheres – had more extensive wiring and connectivity in the early starters. The wiring of the late starters was not much different from that of non-musician controls. This makes sense as the corpus callosum aids speed and synchronisation in tasks involving both hands, such as playing musical instruments (Journal of Neuroscience, DOI: 10.1523/jneurosci.3578-12.2013). Christopher Steele of the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany, says this is the most compelling evidence yet that younger-trained musicians have an advantage because their training coincides with a key period of brain development. At age 7 or 8, the corpus callosum is more receptive than ever to the alterations in connectivity necessary to meet the demands of learning an instrument.

Polymer’s flips wring electricity from wet surface IT’S quite a mover – but only when damp. A polymer that flips over if it absorbs water has been used to wring electricity from a wet surface. The film could one day allow small devices to run on nothing but sweat, and provide power in remote areas where conventional sources are scarce. When a dry polymer absorbs water, its molecular structure changes. In principle, this can be converted into larger-scale motion and thus supply energy. But until now, attempts to devise a material

powered by the difference in chemical potential energy between a wet and a dry region have not yielded useful motion. Now Robert Langer and colleagues at the Massachusetts Institute of Technology have blended two polymers to create a film that mimics structures found in muscle and plant tissues that bend when humidity changes. When placed on a wet surface, the film curves up at its ends, becomes unstable and flips over. The ends quickly dry out but absorb water again, and the

process repeats. By flipping over repeatedly, the film can travel across a suitably moist surface unaided. The team found that a 4-centimetre-long strip could lift a load 380 times its own mass, and move sideways when carrying a load 10 times its mass. To extract energy, Langer’s team added a layer of piezoelectric material, which produces electricity when squeezed. When a piece of this film flipped over, it generated 5.6 nanowatts of power – enough to fuel a microchip in sleep mode (Science, doi.org/j6w). MICHAEL AND PATRICIA fogden/MINDEN/ngs

Start early for musical genius

The genetics of queenly behaviour FIRE ants are a family divided. When setting up a new colony, young queens go one of two ways. Some strike out on their own and remain independent, stockpiling fat reserves and creating workers that kill rival queens. But others prefer the communal life, joining colonies in which multiple queens reign side by side. By sequencing the fire ant genome, Laurent Keller at the University of Lausanne in Switzerland and colleagues discovered that two chromosome regions, social B (SB) and social b (Sb) determine the two types of behaviour. Each is made up of several hundred genes and inherited as SB/SB or SB/Sb pairs (Nature, DOI: 10.1038/nature11832). Keller suggests that a similar inheritance pattern might also be found in other organisms. “If you have two or more very different types of behaviour within a single species, I’d be ready to guess that this is what’s going on,” he says. It means that complex differences in behaviour and physiology can be inherited as a single unit, says an impressed Daniel Kronauer at the Rockefeller University in New York.

Secrets of the scorpion swallower DEEP in the Sonoran desert, a terrifying creature searches for fresh meat – even venomous scorpions are on the menu. Throwing its head back, the animal howls at the moon. This isn’t a horror movie but a day in the life of the southern grasshopper mouse (Onychomys torridus, pictured), North America’s only carnivorous mouse. It may hold the secret to a new kind of painkiller. The venom of Arizona bark scorpions causes pain and respiratory failure in humans. Yet grasshopper mice eat them without pause, even while being stung. To discover their

secret, Ashlee Rowe of Sam Houston State University in Austin, Texas, and colleagues examined how the venom affected the nerve cells of mice. Scorpion venom usually activates a protein called Nav1.7 that makes nerves fire pain signals to the brain. Grasshopper mice have a mutation in protein Nav1.8 that prevents this signal from reaching the brain. Rowe presented the work at a meeting of the Society for Integrative and Comparative Biology last week in San Francisco. The team is looking at how the mutation blocks signals to aid the design of novel painkillers.

19 January 2013 | NewScientist | 17

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TECHNOLOGY

outside. Neumann thinks they have cracked the problem with a novel arrangement of an outer vacuum vessel and insulating inner layers of plastic and titanium. But however good their technology, they have to contend with an unusual property of superconductors – when the wires sweep through a magnetic field,

“Making a coil that can be cooled while rotating with the turbine blades is a big engineering challenge” their ability to generate current is reduced. That means more coil –Even colder inside the turbines– turns would be needed to make up for the current loss, which would negate some of the weight savings and make the turbines more expensive to construct. “Magnetic flux lines interfere with the wires’ ability to transport Wind turbines built with superconducting innards promise electricity, lowering its to generate far more power – and be lighter to boot performance,” says Venkat Selvamanickam at the University of Houston, Texas, where the US a big challenge. A research project superconductors, which needed Paul Marks government is funding work via dubbed Suprapower, funded by cooling way down to 4 kelvin,” WIND turbines may soon get a the European Union, kicked off in Neumann says. That temperature its Advanced Research Projects supercharge. Turbines wound December to address this problem. difference might not sound much Agency – Energy. Selvamanickam’s with superconducting wire team thinks they have found a way Holger Neumann at the but it means, crucially, that instead of regular copper could to solve this problem – adding Karlsruhe Institute of Technology cooling the magnesium diboride turn today’s 2 to 3-megawatt in Germany and other members superconductor requires just one- 5-nanometre-wide particles of generators into 10-megawatt barium zirconate to the wire. The of the Suprapower consortium seventh of the power. powerhouses, say teams in are betting on a new “high The team will also have to build team found that this “pins” the Europe and the US that are temperature” superconductor, a casing, called a cryostat, in which magnetic flux lines in place as racing to produce the machines. the wires sweep through the field, magnesium diboride, which the superconducting coil will be At heart, a wind turbine is preventing the formation of works at 20 kelvin. “It’s light, kept chilled by gaseous helium. simple – a series of wire coils swirling magnetic vortices that easily made into wires and is This is tricky as its supporting attached to the rotor blade spin in really cheap compared with reduce current flow. So far they structure will act as a “heat the presence of strong magnetic have eliminated 65 per cent of the old niobium-titanium bridge” to the warmer world fields, provided by stationary this current-limiting problem. magnets. This generates a The US team claims to be within current, but the resistance in a few years of building their own copper wire limits the amount 10-megawatt wind turbine, and Lasers could slash wind-turbine as it involves peppering each blade of current that can flow through says that their techniques could power outages, say engineers at with strain sensors. the coils. Making the coils from a make superconducting wires Chonbuk National University in A cheaper answer is to place resistance-free superconductor attractive for distributing South Korea. If the bolts securing a laser on the tower and instead would cut down on weight and electricity as well as generation. turbine blades to a rotor begin to measure the reflection time from boost power generation. “If we can demonstrate this loosen, or blade mass is lost due to every blade as it passes by. This Using superconductors will superconducting-wire technology a lightning strike, a blade can strike way, deviation of all the blades is not be easy, though, partly due to in a wind turbine, we think it’s the turbine tower and fall off. But measured using just one low-cost the ultra-low temperatures they more likely that it will make its monitoring for when a blade starts sensor (Smart Materials and require. Developing a coil that can way into the power cables of to go out of alignment is expensive Structures, doi.org/j62). be cooled while simultaneously the electricity grid,” says rotating with the turbine blades is Selvamanickam. n

Supercool wind power

Merrily spins as laser looks on

19 January 2013 | NewScientist | 19

TECHNOLOGY

Vanishing skyscrapers

robert gilhooly

skyscrapers over 100 metres tall, around 150 of which will be between 30 and 40 years old in the next decade, says Ichihara. This has historically been the age when Say goodbye to explosions; tall buildings can now simply disappear such buildings are earmarked for demolition, but conventional methods are not suitable for such Rob Gilhooly tall skyscrapers. This has prompted IN THE heart of Tokyo an iconic Taisei and its competitors Kajima skyscraper, the Grand Prince Hotel and Takenaka Corporations to Akasaka, is being demolished. develop new demolition systems. But there are no explosives or Kajima’s “cut and down” method wrecking balls in sight. Instead, all dismantles floors from the ground that can be seen is the roof slowly up, while Takenaka’s approach is sinking as the aluminium-clad almost identical to Taisei’s. building shrinks beneath it. Whether the country’s current The demolition is being carried crop of high-rises should have out by the Taisei Corporation, such a short life span is a matter which has developed what it of debate. After Tokyo was shaken claims is a cleaner and more by earthquakes in March 2011, the environmentally friendly way to prominent billionaire property tear down high-rises. Called the developer Akira Mori called for Taisei Ecological Reproduction the country to stop building System, it works from the top skyscrapers over 100 metres high. down, breaking a building apart Instead he suggested lower, widerfloor by floor. The once 140-metre based structures should be built. tall hotel is now missing its top No such restrictions have yet 30 metres. By May it will have been imposed. Takuro Yoshida, a vanished. professor at Kogakuin University The levels being dismantled in Tokyo, argues that newer –Losing height without the dust– engineering techniques could are sealed within an enclosure that wraps around the building keep buildings safely standing says Taisei’s Hideki Ichihara. as the pieces are lowered. By (see time-lapse photo), while huge for longer periods. “The idea Before demolition begins, all recycling building materials and jacks slowly lower the original that buildings are rebuilt on a non-structural elements of the getting rid of heavy machinery roof down as floors are removed. 30- to 40-year cycle is itself about building are removed by hand. that runs on fossils fuels, Ichihara 20 years old,” he says, adding Fully enclosing the demolition Workers then take out beams says, the process reduces carbon area reduces the volume of dust that the ecological benefits of and concrete flooring, which are dioxide emissions by as much particles emitted from the site keeping a building in service carried to ground level by a crane as 85 per cent. by a factor of 100 compared outweigh even the most efficient system that generates electricity In Japan alone there are 797 with conventional methods, means of demolition. n

Buzzing steering wheel to guide dazzled drivers WORRIED that the sun in your eyes will impair your driving? For the first time, a vibrating steering wheel will tell drivers where to steer when undipped headlights or other visual impediments leave them temporarily blinded. Eelke Folmer and Burkay Sucu at the University of Reno in Nevada, designed the steering wheel to help 20 | NewScientist | 19 January 2013

cut the accident toll caused by glare, especially in winter, when motorists are most likely to be dazzled by low sun and reflections from snow and ice. Cars with vibrating seats can already warn drivers when another vehicle is approaching in their blind spot. But the team’s design is the only one to help drivers steer using tactile cues. The system relies on car sensors like GPS and lane-keeping cameras to map the road ahead and work out where the vehicle is. When sensors detect the driver may be dazzled and drifting from their lane, the vibro-

tactile system buzzes into action. The vibrations are tuned to 275 hertz, the frequency that our skin is most sensitive to. And the cues are directional, so if a driver drifts left, the left side of the wheel will vibrate – a signal to steer right until it stops vibrating, just like a rumble strip. “It’s fairly easy for the system to anticipate or sense glare conditions and activate itself,” says Folmer.

“If a driver drifts left, the left side of the wheel will vibrate, a signal to steer right until vibrations stop”

The system worked well in tests with 12 volunteers in a simulator, but the drivers’ hands strayed from the left and right vibrators – so the devices may need to be more widely distributed around the wheel. It’s promising work, says Paul Newman, who is developing a driverless car at the University of Oxford. “Touch is an extraordinarily rich sensory pathway and is an ideal way to provide safety-improving hints. In this case, the hints are felt at the very place action is required – on the steering wheel itself,” he says.

Paul Marks n

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One Per Cent

RIVER mussels wearing tiny sensor backpacks could help monitor the Mississippi for dangerous pollutants. The plan is for the mussels to measure the flow of nitrogen-rich fertiliser that courses down the river and empties into the Gulf of Mexico. An excess of the nutrient there can cause dead zones that suffocate marine life. Researchers at the University of Iowa in Iowa City have attached wireless sensor packages to mussels for measuring their “gape” – how much their shells are open. They are also working on monitoring the animals’ heart rate, how much water they filter and when they burrow. Each behaviour changes according to the water conditions. In a previous experiment the mussels’ backpacks successfully transmitted signals to a receiver on the riverbed that relayed the signals to a lab on shore via a wired connection. The researchers are now testing their system on a group of mussels living in a tank, so that they can measure how the mussel shells gape in response to varying nitrogen levels. The advantage of using mussels as a sensing mechanism is that they stay clean, unlike the electronic sensors that are normally used to monitor nitrogen content, says

team member Anton Kruger. “Everything flocks to it and all kinds of muck starts to grow on the device,” he says. “But if you put a mussel out, they clean themselves and live for years and years.” Kruger will present the design for the mussel backpacks next month at the Sensor Applications Symposium in Galveston, Texas. Team member Craig Just says the creatures could also be useful as hazardous waste or spill indicators. “They’d be the canary in the coal mine,” he says. They could also help

“Mussels will measure the flow of nitrogen-rich fertiliser that courses down the Mississippi” researchers understand how mussels feed on nitrogen from rivers. Donna Myers of the US Geological Survey in Reston, Virginia, praised the idea’s creativity, adding that you still need conventional sensors for precise readings of nitrogen concentrations in the river. At the moment the USGS has about two dozen in operation. “But you can’t afford to put sensors everywhere,” Myers says. “It would be wonderful if they came up with something that could be used as an alternative.”

Hal Hodson n

oculus rift

Mussels toting backpacks to keep watch on Mississippi

Throw yourself right into the action Virtual reality will be reborn. Oculus VR hopes to resurrect the fading 1980s dream of fully immersive gaming. And as we found at the Consumer Electronics Show (CES) in Las Vegas last week, the feeling of realism the company’s goggles provide is remarkable. The Oculus Rift headset creates a 3D effect by projecting a different view into each eye. Sensors track your head’s orientation while the images update at 60 frames per second to help you suspend disbelief. Oculus Rift began life as a Kickstarter project and raised almost $2.5 million through the site.

Flashing bulbs know where you are Not all bulbs that flicker are faulty. The ByteLight system uses flashing LED bulbs to pinpoint people’s locations. It is more accurate than WiFi and reaches places that GPS signals can’t. The bulbs flash with patterns that humans can’t see, but a smartphone or tablet camera can. Software works out where a user is by triangulating the locations of two bulbs of a set intensity. The device is being trialled at Boston’s Museum of Science to tell visitors what is nearby.

“It allows you to compute in a way you have never done before” Leap Motion’s Michael Zagorsek shows off a device that tracks each of a user’s fingers independently, at CES last week

University of Iowa

Make yourself a gardening guru Does every plant you own end as a heap of shrivelled leaves? Don’t worry, Flower Power is here to help. Also unveiled at CES, the device is simply a Bluetooth-enabled stick that you shove into the soil next to your plant. Sensors monitor moisture and sunlight levels and send that information to the cloud. A smartphone app warns you, with colour-coded signs, when your beloved flora need a drink.

For breaking tech news go to: newscientist.com/onepercent –Cybermussels taste the river– 19 January 2013 | NewScientist | 21

TECHNOLOGY Insight Next-generation electronics

–Every reach recorded–

Depth-sensors for all The device that powers Microsoft Kinect is making the leap into everyday life WHEN Microsoft’s Kinect gaming shoppers’ behaviour. Because the sensor first exploded onto the gaming sensor can track arm movements – scene in 2010, it wasn’t long before just like in Kinect – it knows when people started getting excited about a shopper has picked up a certain what it might make possible. product. The data is compiled and But despite some imaginative retailers can see a “heat map” of hacks, and even a stint in the operating exactly where on a shelf most theatre, the breakthrough depthcustomers are reaching. sensing technology that made Kinect The sensor is also being put to use such a success has had a hard time by Portuguese firm CoVii, which has moving beyond the lab or living room. written software that lets the sensor Now the firm behind the 3D sensor turn any simple flat-screen TV or at the heart of the Kinect system is monitor into a “touch–sensitive” pushing to make the leap into a wide device – only the user doesn’t have variety of consumer fields far removed “We’re taking our sensor from gaming. way beyond the living At the International Consumer room and putting it into Electronics Show (CES) in Las Vegas almost anything” last week, Israeli firm PrimeSense showed how their depth sensor, called Carmine, is being put to use in myriad to touch the screen. Because it can applications. And a smaller version of detect how far a user’s hand is from the sensor may soon be sitting in your the screen, it lets people interact by smartphone or tablet. hovering their finger a set distance “We’re taking it way beyond the from the surface – something that living room and putting it into almost would be perfect for interactive anything,” says PrimeSense’s head of advertising displays that could be commercial markets, Ohad Shvueli. kept safe behind glass windows. Retail is the sector that looks Meanwhile, California-based to benefit the most. One firm, Matterport has been using the Shopperception, uses the sensor to sensor to cheaply create an accurate, constantly scan the area in front of the 360-degree 3D scan of a room that shelves in a supermarket to gauge is complete within 10 minutes. Such 22 | NewScientist | 19 January 2013

mapping would make buying furniture for your living room a cinch, for example. Styku, also at CES, has been using the sensor to create a virtual changing room where online shoppers scan their bodies at home and create an avatar to try on outfits to see how they look. Sean Murphy, an industry analyst for the Consumer Electronics Association, which organises CES, says 3D sensing and gestural control are poised to become a much bigger part of our lives. “It really is the next frontier for getting people interacting with the world around them,” he says. Shvueli agrees, and is pushing hard for the technology to mature into a mainstay of our everyday lives. “Despite Kinect, 3D sensing is a non-existent market at the moment,” he says. “We are in the very early stages of making it integrated into everything.” To that end, he says a new version of the sensor, called Capri, will bring depth-sensing to mobile devices. Capri is far smaller than the Carmine sensor, thanks to better heat dissipation. “Once Capri is in a tablet or a smartphone it is going to break the mass market wide open,” Shvueli claims. He expects to have Capri sensors installed in commercially available devices next year. Niall Firth n

PLANES and birds aren’t good at sharing air space – bird strikes worldwide cause over a billion dollars in damage every year, and put passengers and crew at risk. To scare avians away, a new device will fire low-frequency sound waves at flocks as they near busy flight paths. Noise makers are often used to scare birds away from airports or contaminated waterways. But loud sounds also annoy any humans within earshot. Now a system developed by Technology International, based in Laplace, Indiana, aims to deter birds using infrasound, below the range of human hearing. The trial version of the Avian Infrasound Non-lethal Denial System has a passive infrasound detector that listens for an approaching flock, and activates a series of rotary subwoofers that generate high-intensity, but low-frequency sound. It worked well in tests. Thunderstorms also emit lots of infrasound, which may be why birds are naturally averse to it, says Abdo Husseiny, the firm’s CEO. Husseiny adds that the system could be used to keep pigeons away from public squares, or divert flocks away from wind turbines. He says that the equipment should be commercially available within two years. David Hambling n

Charles Polidano/Touch The Skies/Alamy

Fancy/Alamy

Low down sound keeps birds away from planes

Aperture

24 | NewScientist | 19 00 January Month 2013 2013

Star racer NOW that’s one groovy star. Seen speeding like a bullet through a cloud of dust and gas, the massive star Zeta Ophiuchi is creating a colourful wave known as a bow shock. This happens because the star’s motion is compressing dust grains like water at the bow of a ship. To the naked eye Zeta Ophiuchi is a placid dot parked in the constellation Ophiuchus. But the infrared vision of NASA’s Spitzer Space Telescope shows how the shooting star is electrifying its surroundings. It creates a scene akin to a UV-triggered fluorescent blacklight poster, says Spitzer image specialist Robert Hurt of the Jet Propulsion Laboratory in Pasadena, California. In this picture infrared wavelengths have been translated into visible ones, with shorter waves in blue, middle waves in green and longer ones in red. That’s why the bright stars glitter like sapphires, while small dust grains fluoresce in a faint teal as they absorb Zeta Ophiuchi’s light. Red in the bow shock comes from the larger, hotter dust grains that can survive the star’s fierce radiation. Given its speed and direction, astronomers think the star once orbited an even heftier companion. But the biggest stars live fast and die young, and its partner exploded in a violent supernova blast that sent Zeta Ophiuchi careening away at a whopping 87,000 kilometres per hour. This isn’t the first or even the fastest runaway but it is perhaps one of the most detailed. “Here you have a star hurtling through space and having a huge impact on its environment,” says Hurt. “It really gives you a general sense of how everything is interconnected.” Victoria Jaggard

Photograph NASA/JPL-Caltech

19 00January Month 2013 | NewScientist | 25

OPINION

Cut the bluster Concerns over the aesthetics of wind turbines need to be heard, but claims that the technology does not deliver are simply untrue, says Reg Platt THE location of the British Isles at Europe’s wild and windy western fringe does not always seem like a blessing. But in one important respect it is: the UK has the greatest potential for wind power, both onshore and offshore, of any European country. Onshore wind power has expanded steadily across the UK in recent years and is a key plank of the country’s commitment to greening its electricity supply. But as the turbines have gone up across the countryside, so has the level of opposition. Wind power has become a deeply divisive issue in British politics. The issue exploded last year when 106 members of parliament, mostly Conservatives representing rural constituencies, signed a letter to Conservative Prime Minister David Cameron. They urged him to cut subsidies for the onshore wind industry, describing wind technology as “inefficient and intermittent”. Things escalated in the autumn when the recently appointed Conservative energy minister, John Hayes, told two newspapers that “enough is enough” and that no new onshore wind farms would be built. He was slapped down by his boss Edward Davey, the secretary of state for energy and climate change and a member of the Liberal Democrat party. But simmering tensions remain at the top level of the coalition government. Another Conservative, finance minister George Osborne, is known to be sympathetic to the anti-wind cause. Wind turbines also became an important point of contention 26 | NewScientist | 19 January 2013

between the parties in a recent frequently make claims about the by-election. shortcomings of wind power. Their Two of the anti-wind main complaints are that the campaigners’ main concerns are turbines are so inefficient that they the impact of turbines on the actually increase carbon dioxide beauty of the countryside and emissions, and so unreliable that the opposition of local people. they require constant backup It is absolutely right that these be from conventional coal and gastaken into account. But they need fired stations. to be balanced against the bulk of If correct, these claims would public opinion, which strongly be devastating to wind power. supports the increased use of But they are not. wind turbines. My organisation, the Institute Any misgivings must also be for Public Policy Research, balanced against the important recently published a report role that this technology can play “We should not sacrifice for the UK, both in fulfilling its opportunities because of climate-change commitments the unsubstantiated claims and for future economic success. of vocal minority groups” Anti-wind campaigners

tackling these questions. Our conclusions are unambiguous. Onshore wind power reduces carbon emissions and is a reliable source of electricity, at least up to the capacity of wind power that is forecast to be installed in the UK by 2020. To answer the carbon question, we used a simple model of the UK electricity market. As demand increases, say on a weekday morning when people are waking up and getting ready to go to work, power plants increase output to meet it. Plants with the lowest marginal cost – that is, those that can produce additional electricity most cheaply – are selected first by the market. Here wind beats gas and coal, as no fuel is needed to generate electricity. The upshot is that, in theory, adding wind power to the energy mix should displace coal and gas, and hence cut carbon. This is backed up by empirical data on emissions reductions from wind power in the US. There is another way of looking at it. In 2011, wind energy contributed approximately 15.5 terawatt-hours of electricity to the UK. If this had been supplied by fossil fuels instead, CO2 emissions would have been at least 5.5 million tonnes higher, and as much as 12 million tonnes higher. As for the important matter of reliability, the obvious worry is that because the wind does not always blow, the system will sometimes not be able to supply electricity when needed. This seems like common sense. However, the reliability of wind

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Reg Platt is a research fellow at the Institute for Public Policy Research, a think tank based in London

One minute with...

Lisa Randall It’s time to stop obsessing about a theory of everything, says one of the world's most prominent theoretical physicists Doesn’t every physicist dream of one neat theory of everything? There are lots of physicists! I don’t think about a theory of everything when I do my research. And even if we knew the ultimate underlying theory, how are you going to explain the fact that we’re sitting here? Solving string theory won’t tell us how humanity was born. So is a theory of everything a myth? It’s not that it’s a fallacy. It’s one objective that will inspire progress. I just think the idea that we will ever get there is a little bit challenging. But isn’t beautiful mathematics supposed to lead us to the truth? You have to be careful when you use beauty as a guide. There are many theories people didn’t think were beautiful at the time, but did find beautiful later – and vice versa. I think simplicity is a good guide: the more economical a theory, the better. Is it a problem, then, that our best theories of particle physics and cosmology are so messy? We’re trying to describe the universe from 1027 metres down to 10-35 metres, so it’s not surprising there are lots of ingredients. The idea that the stuff we’re made of should be everything seems quite preposterous. Dark matter and dark energy – these are not crazy ingredients we’re adding. Did the discovery of the Higgs boson – the “missing ingredient” of particle physics – take you by surprise last July? I was surprised that the Large Hadron Collider experiments reached that landmark. I thought the teams would say something very affirming but the announcement of the discovery was amazing. It was a feat of engineering that they got the collision rate up to what it had to be, and the experiments did a better job at analysing the data. Are you worried that the Higgs is the only discovery so far at the LHC? I’m not worried that nothing else exists. But I am worried that the LHC might have too low an energy.

Profile Lisa Randall is a professor of physics at Harvard University. Her recent books are Knocking on Heaven’s Door (Vintage) and Higgs Discovery: The power of empty space (Bodley Head)

Had the Superconducting Super Collider been built in Texas, it would have had almost three times the energy. There is a distinct possibility we’ll discover things when the LHC’s energy is nearly doubled next year. But it’s too early to see signs of warped extra dimensions – they will take longer to find. What would an extra dimension look like? The best signature of the warped extra dimensions would be seeing a so-called KaluzaKlein particle. These are partners of the particles that we know about but they get their momentum from extra dimensions. They would look to us like heavy particles with properties similar to the ones we know, but with bigger masses. What if we don’t see one? Some argue that seeing nothing else at the LHC would be best, as it would motivate new ideas. I don’t know what dream world they are living in. It would be very hard to make the argument to build a higher energy machine based on the fact that you didn’t see something. Interview by Valerie Jamieson and Richard Webb

19 January 2013 | NewScientist | 27

Christopher Kim

power does not depend on the variability of wind. Instead, it depends on how well changes in wind power output can be anticipated. Forecasts of wind farm output are increasingly accurate, and drops in output can be predicted and compensated for using conventional power stations. In any case, output is surprisingly stable across the country’s entire network of wind farms: when the wind isn’t blowing in one area, it usually is somewhere else. The relatively small changes that do occur are well within the capabilities of existing systems for balancing supply and demand on the grid. Even when winter delivers a “long, cold, calm spell” with low temperatures and little wind, the system can cope. This was demonstrated by a two-week period in February 2010 in Ireland, a country that is much more reliant on wind than the UK. It coped perfectly well. If the UK government caves into pressure and lowers its ambitions for onshore wind, it will make more expensive forms of low-carbon generation a necessity to hit the UK’s target of producing 30 per cent of its electricity from renewables by 2020. The result will be even higher electricity bills. Scaling back on wind would also be a lost opportunity. The natural resource at our disposal, combined with the UK’s engineering heritage, could create significant economic growth and jobs. The concerns of people who do not want wind power on their doorsteps need to be taken into account. We must also be sensitive to the need to preserve areas of natural beauty. But we should not sacrifice important opportunities because of the views of vocal minority groups and their unsubstantiated claims. n

OPINION THE BIG IDEA

Just call off the pregnancy police Can you eat soft cheese? Have a home birth? Exercise? Pregnant women are bombarded from all directions with myths and half-truths, says Linda Geddes IT’S tough being pregnant these days. Apart from the nausea, heartburn, swollen ankles and constant pummelling from within, practically every aspect of your life is under scrutiny. You mustn’t eat too much because it could increase the baby’s risk of obesity and diabetes, but nor should you diet – for the same reasons. And you can forget exercise in case it triggers a miscarriage. Just thinking about it all is enough to raise your blood pressure, except that pregnant women mustn’t get too stressed because that too is bad for baby. Time to chill out? Not so fast: a glass or two is strictly off limits, and so are innocent-sounding spa treatments in case you overheat. Even lying down in bed could cut off the baby’s blood supply.

“I believe that we need greater honesty about what labour entails” Recently the British charity Sense About Science carried out its own preliminary research and evaluated newspaper coverage of pregnancy from 2006 to 2011. It identified no fewer than 138 different factors that allegedly influence the outcome of pregnancy, adding ice cream, night work, sunbeds, perfluorinated compounds in plastic food packaging, hair dye and pet shampoo to the list of things to avoid. Worse, because some 30 per cent of these reports gave no clues about the source of the research cited, there was no way expectant parents could properly assess the risks or judge the quality of the science. It’s not just newspapers. Even health organisations in different countries disagree. Is it safe to eat pasteurised soft cheese? The US Centers for Disease Control says yes; the UK’s Health Protection Agency says no. And home 28 | NewScientist | 19 January 2013

births? The UK’s Royal College of Obstetricians and Gynaecologists and the Royal College of Midwives say yes; the American Congress of Obstetricians and Gynecologists says no. Then there’s disagreement between doctors and midwives over whether to delay clamping the umbilical cord to allow more of the blood in the placenta to flow into the baby’s body, and when to intervene in pregnancies that run over 40 weeks, or if labour is slow. Not surprisingly, when I found myself pregnant for the first time three years ago, I felt overwhelmed, not just by the media but from the offerings of doctors, antenatal teachers and friends. Even complete strangers seemed to think it acceptable to advise me on the wisdom of drinking a glass of wine or carrying a suitcase up a flight of stairs. I was so incensed that I set out to look for the truth behind the old wives’ tales, alarming headlines and possibly problematic government guidelines. What started as a 14-part blog for New Scientist during the last weeks of my first pregnancy developed into a two-and-a-half-year obsession with the science of bumps, birth and newborn babies. Eventually, my book, Bumpology, was born. What I discovered frequently amazed me. I learned how wrong the still popular notion that babies are born “blank slates” really is: newborn babies have some concept of who

Profile Linda Geddes is currently on leave from New Scientist following the birth of her second child, Max. Her book Bumpology is published by Transworld this month

their mother is, of what a human face looks like, and some appreciation of numbers and language. I discovered the evidence is weak for many things that pregnant and breastfeeding women are told to avoid – including exercise and peanuts (increased risk of peanut and other food allergies) – and often contradicted by later studies or meta-analyses. I was also angered. Shortly after starting to write the book, I became pregnant with my second child, and began to revisit much of what I had been told by antenatal teachers first time. I realised that much of it was misleading (some plain wrong) and I began to appreciate the power that the words “increased risk” can have over our decision-making. For example, when I sailed past my due date in my first pregnancy, I tried everything to kick-start labour, from pineapple to curry to sex,

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me how common tearing is – and that it isn’t so bad, but that if you feel swelling, heat or discharge from the wound you should insist on speaking to a doctor. And I wish someone had warned me what might happen if I got constipated through not drinking enough, and told me that it is normal for your breasts to become engorged, and that lying in a warm bath and massaging the milk out can help.

Meyer/Tendance Floue See left: Ian Patrick/Alamy

Birth support

because I had been told that if I was induced I was at increased risk of having an epidural or a caesarean section. I had also been warned these interventions would, in turn, increase my risk of tearing, decrease the chances of bonding with, and/or being able to breastfeed my baby. Quite apart from failing to find evidence to support the idea that curry, pineapple or sex induce labour, I also discovered that if you study pregnant women who are 2 weeks overdue, you find that they are actually less likely to need a C-section if they opted to be induced rather than waiting for the baby to arrive. And although there is an increased risk among pregnant women generally of having an instrumental delivery (involving forceps or a suction device called a ventouse) if you request epidural anaesthesia, the absolute

risk is very small indeed: 20 women would need to have an epidural for one additional instrumental delivery to take place. I also felt short-changed by antenatal teachers who glossed over the uncomfortable realities of natural birth: 85 per cent of women will experience some tearing; you can end up so constipated that the lining of your anus may be damaged; while 36 per cent of women anticipate suffering severe pain during labour, 65 per cent report experiencing it; and when your milk comes, your breasts will become so hot and swollen that you may fear someone has replaced them with a sack of boulders. What’s more, all of this is perfectly normal, and there are things you can do to alleviate the suffering and reduce chances of infection. I wish, for example, that someone had told

I strongly believe women should have the birth they want, but they need support and solid facts when they make their decision – and they need to appreciate that labour does not always proceed smoothly. For example, according to the voluntary organisation Birth Choice UK, in 2010 just 42 per cent of UK women had a normal birth without medical intervention (including epidural anaesthesia). Some experts argue fewer women would undergo unnecessary medical procedures if they were in a midwife-led unit. One unit, at the City Hospital, Birmingham, achieved a normal birth rate of 54 per cent, so it seems steps can be taken to increase women’s odds of delivering naturally, but there will always be a significant number who need medical help. This is not a choice, and it is irresponsible to suggest that women have a huge amount of control over what happens to them during labour. I don’t want to scare pregnant women, but I believe that we need greater honesty about what labour entails so people are more open to the possibility of drugs, or to the idea they may need medical assistance without feeling like failures for not living up to a fantasy of what birth should be like. I say this because at least one study, at Brigham and Women’s Hospital in Boston, Massachusetts, found that women who plan a natural birth and end up requesting an epidural say it made their childbirth unsatisfying, even though it relieved pain and they gave birth to a healthy baby. Among the reasons given were a sense of failure, and misplaced concern that an epidural might have harmed their baby. The study also suggested that those women who went into birth with their eyes open were the ones who achieved their goal of a natural birth. It’s time for society to reconsider the effect of this advice, moral judgement and scaremongering on pregnant women and new parents. Having a baby can be one of the greatest joys life bestows, but it is hard work. We can do without unnecessary guilt, anxiety and doubt – but not without the facts. n 19 January 2013 | NewScientist | 29

OPINION LETTERS Synaesthesia for all From Amy S. Bouska Your look at tapping multiple senses to enhance enjoyment of food seemed to be describing undiagnosed synaesthesia – a crossing of the senses (22/29 December 2012, p 60). Perhaps, rather than being either synaesthetes or “normals”, we all exist on a scale of greater or lesser synaesthesia. And for most people this synaesthesia could be subconscious. As a synaesthete myself, I don’t think I could ever associate yellow with sourness because it is the colour of “9” for me. But then I haven’t tried putting a printout of this number next to my dinner plate to see what the taste effect would be (if any). Cresco, Iowa, US

Flintstone flicks From Ted Rockley I am grateful to Catherine Brahic for confirming my belief that animation is deeply embedded in the human psyche. Her wonderful article describes some of the

requires little imagination to understand how potent such an experience would have been. Perhaps cinema-going could be interpreted as a modern manifestation of that ancient cave experience. Urgent research is required into any grains or seeds found on the cave floor. I’m betting they had popcorn too. London, UK

ingenious methods that our ancestors came up with to create a sense of movement in cave art and artefacts (22/29 December 2012, p 44). Animation predated the cinema, with “toys” such as the modern zoetrope creating the illusion of movement, but until now few people would have appreciated that animation began thousands of years ago. However, there is more to the astonishingly skillful, beautiful and stylistic imagery of such ancient artists. It implies highly ordered social groupings, a storyteller, an audience and perhaps music and dance. The stories may have had a purpose – to teach, to recall, to worship. It

Enigma Number 1732

Cache up front BOB WALKER Joe was having a dream. He was planning a solo trek to the North Pole and back, a total of 500 miles. His main problem was not being able to carry daily supplies sufficient for more than 240 miles, that is, in addition to the rest of his kit. He calculated how many supply

dumps he would have to make on his way to the pole. After he had calculated the minimum total number of miles he would have to walk, setting up the dumps and getting to the pole and back, he woke up. How many miles would Joe have to walk?

WIN £15 will be awarded to the sender of the first correct answer opened on Wednesday 13 February. The Editor’s decision is final. Please send entries to Enigma 1732, New Scientist, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to [email protected] (please include your postal address). Answer to 1726 Conspicuous consumption: Fuel consumption for the return journey is 62 miles per gallon The winner Tom Flannery of Derby, UK

30 | NewScientist | 19 January 2013

A walnut would do From Andrew Lenton Bob Holmes explores ways of avoiding a scalding while carrying a hot drink (22/29 December 2012, p 65). I am sure the answer to this appeared in New Scientist about 25 years ago. The solution, at least for African women carrying pots of water, is to float a coconut shell in the liquid. This acts as a damper on surface motion and prevents slopping. In a cup a smaller device would suffice. Another way is to drink cappuccino; the milk froth is an efficient damper. Eindhoven, The Netherlands

Astro-pology From Derek Long Feedback, and correspondent Bryn Glover, need to go back to their roots (22/29 December). The word “astronomy” has nothing to do with naming, but everything to do with nomos – law, order, arrangement. But I agree that “astrology” might be a better word for what astronomers do. Liverpool, UK

Drink to that From Malcolm Bacchus Your article on logician George Boolos’s hardest logic puzzle ever and related problems (22/29 December 2012, p 50) reminded me of the truth teller/ liar problem set by science writer Martin Gardner in 1959. Readers

had to find the correct road to a village by asking one question of a liar or truth teller, knowing the status of neither, nor the words for “yes” and “no”. After his original problem was published in Scientific American Gardner got a letter from Willison Crichton and Donald E. Lamphiear of Ann Arbor, Michigan, suggesting an alternative question to solve the puzzle: “Did you know that they are serving free beer in the village?” The truth teller answers “no” and sets off for the village; most liars will answer “yes”, but still set off for the village. In each case, the questioner simply follows. This would work just as well today. Philosophy and logic may change and develop, but the desire for free beer is timeless. London, UK

Gut reaction From Caroline Herzenberg Your look at the influence of the enteric nervous system notes that a lot of the information the gut sends to the brain affects wellbeing, but not in a conscious way (15 December 2012, p 38). Perhaps the subconscious “ gut instincts” and “gut reactions” that we experience may involve not just us, but also our symbiotic gut bacteria communicating information to our bodies, perhaps not just for our benefit but for their own. Chicago, Illinois, US The editor writes: n See our recent feature for the latest on the influence of gut bacteria (12 January, p 30). From Alastair Dobbin It is always unhelpful to separate the brain and the body into distinct entities; this only leads to inaccuracies and supports the discredited idea that we can, for instance, “think” our way out of depression. The brain cannot survive without the body, and

To join the debate, visit newscientist.com/letters

without the body there can be no consciousness. Edinburgh, UK

Seeing red From Vernon C. Barber Your report on detecting longer wavelengths of red light with a modified human visual protein (15 December 2012, p 19) suggests a way for us to see auras. If some people naturally have mutated versions of such proteins that are stimulated by infrared radiation, then the phenomenon would be possible. Westcliff on Sea, Essex, UK The editor writes: n We recently published a story on auras (5 January, p 13). They do exist for some people, but it’s likely they stem from rewiring in the brain rather than differences in proteins in the eye.

Expert view From Peter Bauer Jeremy Howard of Kaggle, a website that hosts problemsolving competitions, champions data science over experts for solving predictive problems in many disciplines (1 December 2012, p 28). This

struck a chord, as I have found that expert knowledge can get in the way when trying to solve cutting-edge problems. But before we decide to shoot the experts, let’s take a broader

look. It’s only human to value our hard-won knowledge, and most of it will turn out to be correct. We do need curious and creative people unconstrained by existing ideas to advance any field, but we also need knowledgeable people to guide their efforts so we don’t keep reinventing the wheel. Egg Harbor City, New Jersey, US

Blowing a fuse From C. Leroy Ellenberger The “electric universe” described in Greg Shanahan’s letter (22/29 December 2012, p 41) is a misconception supported with naive analogies to laboratory plasma effects, and refuted by the vast majority of astronomers. He mentions physicist Anthony Peratt as a proponent. But Peratt accepts the standard model for thermonuclear stars and has disavowed the idea of electrical engineer Donald Scott, also mentioned by Shanahan, that stars are powered by massive flows of galactic electrons rather than fusion. St Louis, Missouri, US From W. T. Bridgman Peratt’s plasma galaxy model, while an interesting alternative in the 1980s, failed later key observational tests. The orbiting Cosmic Background Explorer (COBE) and the later Wilkinson Microwave Anisotropy Probe found no trace of the spaghetti-like streamers of microwave emission that Peratt predicted would be created by galaxy-powering electric currents. Peratt’s models could not reproduce the uniformity of the cosmic microwave background. And if stars were powered by external electric currents rather than fusion then the accompanying particle fluxes and fields would damage satellites and kill astronauts, which of course is not something we see happening. Silver Spring, Maryland, US

Language loss From Duncan Cameron Why do so many languages coexist in some parts of the world (8 December 2012, p 38)? Most languages, like many species, become extinct, making the history of language, especially how it dies out, a bit of a sketchy affair. However, I believe when states form they squeeze out small languages. Regions of the world where state formation is relatively recent – such as New Guinea and eastern Siberia – are the areas with greatest linguistic diversity. China and Europe, with a long history of strong states, have fewer diverse languages. New Guinea’s multiplicity of languages is remarkable – but I don’t believe it can be explained by inter-group rivalry and tropical climate. Brighton, East Sussex, UK

labelled Project Habbakuk. It showed a test of something which was definitely not an iceberg ship. In fact, it resembled a semisubmersible rig, with a deck above wave height on very stout columns supported by a pair of submerged pontoons. What other ideas might Habbakuk have included? Kennington, Kent, UK

Bitter lesson From Donald A. Sands How ironic that coffee should become a victim of global warming, considering that its

Mosquito Nobel From Ullrich Fischer You reported research online showing how the mosquito avoids infection by the malaria parasite as it passes through its body (11 December 2012, newscientist. com), with talk of bioengineering its immune system to prevent transmission altogether. If this can be made to work in mosquitoes and leads to a series of attacks on other diseases transmitted in a similar way, there should be a Nobel prize in it. Surrey, British Columbia, Canada

More than ice From Tom Groves You told the tale of research during the second world war on ships made of ice under the guise of Project Habbakuk (22/29 December 2012, p 63). I suspect it was a cover for wider work. When at the National Physical Laboratory in the late 1960s, a colleague showed me a film

export worldwide is one of the causes (5 January, p 33). The mass transportation of products across the planet has a huge carbon footprint, and is a major contributor to climate change. Mount Horeb, Wisconsin, US

For the record n In the map to accompany our look at how to protect New York from storm flooding (5 January, p 6) we wrongly labelled the Bayonne and Jersey City area as Manhattan. Letters should be sent to: Letters to the Editor, New Scientist, 84 Theobald’s Road, London WC1X 8NS Fax: +44 (0) 20 7611 1280 Email: [email protected] Include your full postal address and telephone number, and a reference (issue, page number, title) to articles. We reserve the right to edit letters. Reed Business Information reserves the right to use any submissions sent to the letters column of New Scientist magazine, in any other format.

19 January 2013 | NewScientist | 31

jirayu koo

COVER STORY

32 | NewScientist | 19 January 2013

Our hopes of finding an ultimate theory depend on upsetting a balance that Einstein cherished, says Stuart Clark

Differently equal C

OINCIDENCE is not generally something scientists have much truck with. If two things are genuinely unrelated, there is little further of interest to be said. If the coincidence keeps turning up, however, there must be some deeper underlying link. Then it is the job of science to tease out what it is and so explain why there was no coincidence in the first place. That makes it rather odd that a large chunk of modern physics is precariously balanced on a whopping coincidence. This coincidence is essential to the way we view and define mass. It is so fundamental to the world’s workings that most of us encounter its consequences every day without  giving them another thought. Yet it has vexed some of the best minds in physics for centuries. Galileo and Newton grappled with it, and ended up just accepting it, rather than understanding it. Einstein went one better: he declared it a principle of nature. He went on to use this “equivalence principle” as the fundament of his general theory of relativity, still our best stab at explaining the mysterious  force of gravity. But there is a problem. If we want to find some bigger, better theory that can unify gravity with the other forces that dictate the world’s workings, the equivalence principle cannot stay. We must either unmask this coincidence – or radically rethink how physics can progress from here. There are several versions of the equivalence principle, but all boil down to one idea: that the effects of gravitational fields are indistinguishable from the effects of accelerated motion. A thought experiment of Einstein’s expresses it best. Imagine a person

standing inside an elevator on Earth. What keeps their feet firmly planted on the floor? The inexorable pull of gravity downwards, of course. Now imagine the same person in the same lift, but in empty space far from any gravitating object. In this case a rocket just so happens to be pushing the lift up in empty space with the same acceleration that Earth’s gravity produces. The passenger will remain squarely on the lift floor in exactly the same way (see “An enigmatic equivalence”, page 34). How so, when there is no gravity involved? In this case, it is the person’s inertia that is preventing them floating upwards. Inertia is the natural resistance of any body to acceleration – the same effect that pushes you back into your car seat when the driver puts their foot down. The two elevator situations have a common property, mass. But the two masses come from very different places. One, gravitational mass, is something that responds to the pull of gravity, tending to accelerate a body in a gravitational field. The other, inertial mass, is the property of a body that opposes any acceleration. Another way of stating the equivalence principle is to say that these two masses are always numerically exactly the same. The consequences of this coincidence are profound. If the two masses weren’t the same, objects of different masses could fall to Earth at different rates, rather than all accelerating in the same way in a gravitational field. This “universality of freefall” was apocryphally first tested by Galileo dropping a bag of feathers and a bag of lead shot from the Leaning Tower of Pisa. In fact, the equality of gravitational and inertial mass dictates all > 19 January 2013 | NewScientist | 33

An enigmatic equivalence An enigmatic equivalence gravitational motion throughout the universe. If gravitational mass responded just a little bit more to gravity than inertial mass does to acceleration, for example, then planets would orbit their stars and stars orbit their galaxies just a little bit faster than they do. Yet there is no obvious reason why this correspondence should be so. It was only by assuming it was that Einstein fully developed the strange contortions and contractions of time and space he had first introduced in his special theory of relativity in 1905. What if a massive object such as a planet, Einstein wondered, squeezes the surrounding space into successively more compact volumes the closer you get to it? As something moved towards the planet’s surface, it would then take less and less time to cross these compacted spaces: it would appear to accelerate.

The odd force By 1916, this thought had guided Einstein to his general theory of relativity. What looks like gravity is just uniform motion through a progressively compacted space. And if there is no gravity, gravitational mass is fictitious too. The only mass at work in the universe is the one that gives a body its inertia. The coincidence behind equivalence disappears. General relativity is, as far as we have tested it, peerlessly accurate, predicting the positions of celestial bodies and guiding our satellites with minute precision. Yet there is something odd about it that physicists don’t like. All the other forces of nature are transmitted between bodies by physical, if ethereal, quantum particles. The electromagnetic force, for example, is transmitted between bodies with electrical charge by the exchange of the massless particles called photons. Outwardly, gravity works in exactly the same way. It looks like a duck, swims like a duck – but it can’t quite be made to quack like a duck. Attempts to make gravity quack with a quantum voice are the guiding thought behind string theory and other projects to construct all-embracing “theories of everything”. But if gravity is to be reborn as a real force, it needs something to latch on to, just as electromagnetism latches on to electric charge. It needs a gravitational mass that is separate and distinct from inertial mass. That means progress towards a theory of everything has an essential first step: slaying Einstein’s holy cow. “Any theory of quantum gravity must violate the equivalence principle at some level,” says Ben Gripaios, a theoretical physicist at the University of Cambridge. 34 | NewScientist | 19 January 2013

Einstein’s equivalence principle states that the physics of acceleration and gravity Einstein’s equivalence that the physics acceleration andcase gravity work in exactly the sameprinciple way. Butstates there’s no reason why of that should be the work in exactly the same way. But theres no reason why that should be the case Accelerate a rocket in gravity-free space and a body’s inertial mass Accelerate a rocket in gravity-free will resist spacethe andmotion a body’s inertial mass will resist the motion ACCELERATION (a)

The mutual attraction between gravitational masses is what The mutual attraction between keeps our feet on masses the ground gravitational is what keeps our feet on the ground

MASS (m) BODY MASS (m)

ACCELERATION (a) GRAVITY (g) GRAVITY (g)

MASS (m) BODY MASS (m)

EARTH MASS (M) EARTH MASS (M)

In all situations In all situations inertial mass gravitational mass inertial mass gravitational mass acceleration gravity acceleration gravity It’s only by assuming the equivalence principle is true that we can explain It’s only because equivalence principle toground be trueat that that bodies at the the same distance from Earthappears fall to the thebodies same rate at the same distance from Earth fall to the ground at the same rate Newton’s 2nd law of motion Newton’s gravitational law Newton’s 2nd law of motion Newton’s gravitational law

force = If then

mass

m

acceleration mass force = acceleration a m mass x = m x a m =

x

then

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a

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G M

r between body Distance and centre of thebetween Earth body Distance and centre of the Earth

m=m m=m

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Gravitational constant Gravitational constant Mass of Earth Mass of Earth G M

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At a distance (r) from Earth’s centre, At adue distance (r) (g) from Earth’sTHE centre, the acceleration to gravity is ALWAYS SAME

the acceleration due to gravity (g) is ALWAYS THE SAME

How? One tried and tested method is to attempt to prove that the two masses aren’t actually equivalent at all – just very, very close. Even the slightest sliver of a difference would mean that general relativity is built on an approximation and that a deeper, more precise theory must exist. “If someone finds a difference then we have made a major breakthrough,” says Claus Lämmerzahl of the University of Bremen in Germany. A way to do this is to continue on in the spirit of Galileo’s Leaning Tower experiments, testing the universality of free fall and other

”Gravity looks like a duck and swims like a duck – but it can’t quite be made to quack like a duck”

consequences of the equivalence principle in the hope of teasing out some tiny anomaly – so far with little success (see “Drop the subject”, page 35). Meanwhile, theorists are picking at a different thread. They point out that whether or not Einstein was right about there being no gravity, just inertia, no one has yet come up with a convincing explanation of inertia. “We do not yet know how to define it,” says Gripaios. “We know it must be related closely to mass, but until we can define it precisely and know how to measure it, there can be no theory for it.” One thing’s for sure: it doesn’t all come from the Higgs field, feted as the giver of mass. Evidence for the existence of this field and its associated particle was presented by physicists sifting through the debris of particle collisions at the Large Hadron Collider at CERN near Geneva, Switzerland, last year. But while the

Looming 146 metres over the north German plain like a great white rocket poised for take-off, it’s hard to ignore the University of Bremen’s “drop tower” (picture, right). Inaugurated in 1990 as part of the Center of Applied Space Technology and Microgravity (ZARM), it provides up to 9.3 seconds of free fall in which to conduct experiments. So far tests of rubidium and potassium atoms in free fall have provided no deviation from the behaviour predicted by the equivalence principle (see main story). The atoms have been found to fall at the same rate to accuracies of 11 decimal places. At the University of Washington in Seattle, meanwhile, Eric Adelberger and his “Eöt-Wash” team use a high-tech set of scales known as a torsion balance to compare the motions of standard masses made of different elements, including copper, beryllium, aluminium and silicon. They hold the record for test accuracy, with no violations of the equivalence principle to 13 decimal places. At some point, however, these earthbound experiments are going to hit a brick wall. “It is getting harder to make the instruments better,” says Adelberger. Working somewhere where gravity is a lot smaller would make any deviations from equivalence a lot easier to spot.

The French-led MICROSCOPE mission due to launch in 2016 will do just that, testing the motions of masses of platinum and iridium in the microgravity conditions of space. “MICROSCOPE will achieve an accuracy 100 times better than a laboratory on Earth,” says Claus Lämmerzahl of ZARM. His organisation is testing the satellite’s accelerometers in their drop tower, and also developing the software needed to analyse the satellite’s final results. An even more sensitive mission, the Space-Time Explorer and Quantum Equivalence Principle Space Test, is currently being evaluated by the European Space Agency, with a decision on funding due by the end of this year. ZARM

Higgs field is thought to give fundamental particles such as electrons and quarks their mass, when quarks combine into the heavier particles, protons and neutrons, that make up the bulk of normal matter, the resulting mass is roughly a thousand times the summed mass of the constituent quarks. This extra mass comes not from the Higgs mechanism, but from the energy needed to keep the quarks together. Somehow, these two effects must combine and latch on to something else to create the property of a body’s resistance to acceleration. “There is no way the Higgs alone can be some sort of mysterious ingredient that gives inertia,” says Gripaios. What then? One suggestion has its origins in work by Stephen Hawking in the 1970s. Ironically, it was motivated back then by a strict application of the equivalence principle. Hawking was investigating the properties of black holes, the unimaginably dense gravitating bodies whose existence is a central prediction of general relativity. He suggested that a black hole should be an apparent source of radiation, because pairs of quantum particles that constantly pop up in space would become separated close to a black hole, with one being sucked in and the other spat out. That led the Canadian physicist William Unruh and others to suggest that, if gravitation and acceleration really are one and the same thing, similar emissions should be a feature of any body accelerating in a vacuum.

zarm

Drop the subject

Nothing doing Like Hawking’s radiation, Unruh’s has never been unambiguously detected. The accelerations necessary to achieve a measurable effect in a lab are generally too high, although some argue the effect has been seen with electrons accelerated in the high magnetic fields of particle accelerators. A decade or so on from Unruh’s original work, astrophysicist Bernard Haisch of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and electrical engineer Alfonso Rueda of California State University in Long Beach were playing with a similar idea when they realised the vacuum’s interaction with an accelerating body would not just occur on its surface, but permeate its entire volume. That could produce a force that acts in the opposite direction to the body’s movement. They originally likened it to the way in which charged particles moving through a magnetic field experience a force – the Lorentz force – that affects their motion. In this case there were electromagnetic

If objects fall at different rates under gravity, the equivalence principle is broken 19 January 2013 | NewScientist | 35

Dark inertia

jirayu koo

In the 1930s, we noticed that galaxies spinning around other galaxies were not moving as Newton’s and Einstein’s laws of gravity dictated. A few decades later, something similar was observed of the rotation of individual spiral galaxies. It was almost as if some invisible matter was whirling the matter we could see around faster. That idea has now become mainstream: standard cosmology textbooks will tell you that “dark matter” outweighs normal matter by a factor of 5 to 1. Yet despite particle physicists supplying an almost endless list of hypothetical particles that might fit the bill, to date none has been definitively detected. An alternative first championed in the 1980s by Mordehai Milgrom, a physicist then at Princeton University, is that gravity must somehow be modified at a galaxy’s edges. This could be explained if there was a drop in inertial mass without a drop in gravitational mass for stars experiencing the ultra-low accelerations found at the outskirts of galaxies. This would naturally make them move faster. If vacuum interactions can really bring this about (see main story), they could be just the ticket to mimic dark matter.

interactions with the quantum vacuum. “It appears to be exactly what you need for inertia,” says Haisch.

Anomalous accelerations Mike McCulloch of the University of Plymouth, UK, thinks such interactions are also just what you need to break the equivalence principle. One prediction made of Unruh radiation is that, like the rays emitted from a hot body, it comes in a spectrum of many different wavelengths. For very small accelerations, the temperature of the radiation that a body “sees” from the vacuum is low, and dominated by very long wavelengths. Make the acceleration very small indeed, and some of these wavelengths become longer than the size of the observable universe, effectively cutting them off. In this case, according to calculations McCulloch did in 2007, originally to explain the seemingly anomalous accelerations of the Pioneer spacecraft as they crossed the solar system, the total amount of Unruh radiation experienced by a body would drop, and it would feel less of an opposing force. Its inertia would thus fall, making it easier to move than Newton’s standard laws of motion dictate – and cutting the connection with gravitational mass. 36 | NewScientist | 19 January 2013

The problem with this idea is testing it. In the high-gravity environment of Earth, accelerations small enough for the effect to be observed would not be easy to manufacture. But its effects might well be seen in a lowgravity environment such as that found at the edge of a galaxy. Indeed, looking at the anomalous motions of most spiral galaxies, McCulloch suggests this mechanism could also explain another enduring cosmic mystery – that of dark matter (see “Dark inertia”, above). It’s fair to say such ideas have not set the world alight. When Haisch and Rueda came up with their mechanism, NASA was sufficiently impressed to fund further study and the duo also attracted some $2 million in private investment. But the lack of testable predictions of how the effect might manifest itself led the money and interest to dry up. Nevertheless, a traditionalist such as Lämmerzahl thinks we should not dismiss the idea out of hand. “Even though I follow more the ideas of string theory, these ideas of vacuum interactions are not nonsense,” he says. “We need to look at them seriously and decide whether they give us new ways to test the equivalence principle.” One proposal to do that was made in 2010 by a trio of Brazilian astronomers led by Vitorio De Lorenci of the Federal University of

Itajubá. They suggested using a spinning disc to cancel out the accelerations produced by Earth’s rotation and its movement through space. At minuscule accelerations, the disc’s inertia would drop, meaning it would spin faster than expected from Newton’s laws. Despite a relatively modest cost, however, no money has yet been forthcoming to fund the experiment. And so the deadlock remains until someone delivers either an experiment that exposes the equivalence principle as a sham, or a theoretical idea that shows why it must be just so. But if in the end gravitational mass is indeed just inertial mass in another guise – whatever inertial mass is – then it will be the quantum theories of gravity, including string theories, that will find themselves laid upon the sacrificial altar. Paths to a theory of everything will become even more winding. If gravity is not a force, but truly an illusion that springs from the warping of space, as described by general relativity, we will have to look more closely to understand at a basic level what makes that warping come about. Just a coincidence? This is one that science is not finding so easy to dismiss. ■ Stuart Clark is a consultant to New Scientist and the author of The Sky’s Dark Labyrinth trilogy (Polygon)

The condom has remained unchanged for decades, but not because it cannot be improved. Hannah Krakauer goes in search of new designs

See ya, latex!

PATRICK LLEWELYN-DAVIES/SCIENCE PHOTO LIBRARY

I

Simple and effective, what’s not to love?

F I didn’t already know what they were, I would have difficulty identifying the objects in front of me. There are about 20, mounted on a rack of vertical wooden pegs and illuminated into ghostly shadows by a light box beneath. They resemble elaborate sculptures in translucent resin. One looks like a thin, hollow lemon juicer; others are like accordions or abstract spaceships. Designers Danny Resnic and Ray Chavez joke that they used to keep these racks in the window since passers-by had no chance of guessing what they were. And it’s true; they share only the most rudimentary qualities with what most people think of when they think of a condom. Despite being available in various colours, flavours and textures, modern condoms all follow a basic design that has been with us for more than 150 years: a rubber tube with one end sealed up. But perhaps not for much longer. The first reference to condoms in the medical literature was by Gabriele Falloppio, a 16th-century Italian anatomist who is best known for describing the fallopian tube. In a posthumously published article in 1564 he claimed to have invented a linen sheath that could prevent syphilis, which he got 1100 men to try out. Linen was eventually supplanted by various animal skins, intestines and bladders. Casanova reportedly used, but did not like, them. The invention of vulcanisation by Charles Goodyear in 1844 made rubber a viable condom material, though the earliest rubbers were as thick as a bicycle inner tube with a seam up the side. The advent of liquid latex in the 1930s allowed condoms to become thinner, stretchier and last longer on the shelf. Since then, condoms have remained fundamentally unchanged. But not because there is no room for improvement. Condoms may be functional, but they have never really been sexy. In the > 19 January 2013 | NewScientist | 37

”Spray-on condoms were cast aside when none of the volunteers were willing to insert anything other than a finger into the machine”

origami condoms

beginning, that was part of the point, since the health authorities naively thought condoms would discourage people from having sex, thus halting the spread of disease. A few radical alternatives have been attempted but none have risen to the challenge. Female condoms made their debut in 1993 to overwhelmingly negative reviews. Made of polyurethane and sporting a baggy and intrusive design, they frequently slipped out of place and made an unfortunate crinkling sound during sex. In 2006, German entrepreneur Jan Vinzenz Krause invented the spray-on latex condom, only to cast it aside when none of his volunteers were willing to insert anything other than a finger into the latex-spraying machine. The potentially troublesome 3 minute drying time was thus never properly road-tested. The latex condom’s cheapness and simplicity are evidently hard to beat. But condoms may not remain so homogenous for long. Researchers and designers are reexamining them from bottom to top, looking at their intended functions of contraception and disease prevention and digging deep to see if those goals can’t be accomplished in a rather more elegant fashion.

Latex condoms operate under the basic principle of transferred sensation: the latex is sufficiently thin for the penis to feel contact. This is why the few genuine condom innovations that have been made are in the realm of thinness. But the obvious problem with making a material thinner is that it is more liable to break. Resnic’s experience in this area gave him a compelling motivation to improve on the design. In 1994 he learned that he was HIV positive, the likely result of a split condom.

10bn condoms used in 2005

A sculpture in silicone, half contraceptive, half sex toy (right) 38 | NewScientist | 19 January 2013

He was flabbergasted that it was possible for a product on which people rely so heavily to simply fail. But when Resnic, founder of a Los Angeles design company called Strata, began to investigate he quickly ran into a barrier. Condoms are made by dipping a mould into a vat of liquid latex which is allowed to dry before being rolled off. That means the design options are limited. The production method also explains why they have to be scrolled on. So he decided to start from scratch, first turning to a new material: silicone. Stretchier and more flexible than latex, silicone also turns out to be better at blocking viruses and bacteria. It can also be folded accordion-style, which means it can be slipped on rather than rolled. Where silicone really shines is in the pleasure department. Resnic’s “Origami” condoms are thicker and looser than latex ones, but this actually becomes a design feature. By adding textures and ridges, Resnic says he can make sex with condoms feel better for both partners than sex without. The result is what he describes as a hybrid sex toy and contraceptive. The prototypes on display represent a series of brainstorms and experimentations with silicone’s mouldable potential. The latest version even includes a backflow-prevention reservoir at the tip. Instead of just including a teat at the end to catch semen – from which it can easily escape – Resnic has created a separate chamber blocked by a one-way valve that he compares to a lobster trap: liquid can get in, but it cannot get out again. The condoms are now ready to be put to the test. Resnic and his business partner Chavez have received funding from the US National Institutes of Health to carry out clinical trials of three types of condom: a male condom, a female condom and a specialised anal sex condom which, if it passes, will be the first condom approved for anal sex by the US Food and Drug Administration. The three separate trials, conducted by researchers at the California Family Health Council, RTI International and the Fenway Institute in Boston, are in the very earliest stage. Participants are given a couple of different prototypes and are asked to try them. For safety reasons, there is no partner involved in this stage, so participants are instead asked to simulate sex with their hand or a dildo. The feedback thus far has been positive, at least according to testimony the company allowed me to see. “Terrific,” commented one

tester. “Would make anyone use a condom,” said another. Still others said they were “really enjoying the feeling”. The condoms still need to be tested by couples before larger-scale studies can start, and then there’s the commercialisation process. But Resnic and Chavez are convinced that their emphasis on pleasure is going to make condoms more popular. “The reason our focus is on pleasure is that’s what’s going to keep people using condoms,” Resnic says. “We’re developing ones that people are going to like.”

Despite safety testing, condoms can fail

Elsewhere in the world there are other very good reasons for rethinking the condom. In many parts of the developing world where HIV is prevalent, resistance to condoms among men is fierce. For these people, silicone condoms may not gain much traction. Instead, microbicide gels and creams have been seen as a discreet solution to the problem many women have getting their partners to use condoms. The polymer gel sticks to mucous membranes in the vagina and acts as a temporary internal condom that eventually dissolves, with the male partner none the wiser. Because it is a physical barrier, the gel stops viruses from infecting host cells, and has even been shown to interfere with the maturation process of HIV. But in recent years enthusiasm for microbicides has waned, since chemicals that block HIV in the test tube often fail when tested in the real world. The Alliance for Microbicide Development, an alliance of pharma companies and not-for-profit labs, closed in 2009. Not everyone has given up on them, though. Rabeea Omar, an infectious disease researcher at Laval University in Quebec, Canada, has held fast to the belief that the problem was not with the gel, but how it was applied. So he asked women to apply the gel using a standard applicator with a single hole at the top – the same kind used to apply yeast infection medications. Then he gave them an MRI scan to see where the gel was actually going and found that it stuck only to the surface of the cervix without covering the rest of the vagina. So Omar and his colleagues set out to design a better applicator. Rather than having just one hole at the tip, theirs has many small holes all over the surface, spreading the gel more evenly. Results coming back from clinical trials conducted in Cameroon are extremely promising, he says. When applied with his

Goh Seng Chong/Bloomberg via Getty Images

Invisible condoms

team’s “Invisible Condom” applicator, MRI images show the gel is going and staying right where it needs to be, forming a thin layer that lasts for six hours. Getting the applicator onto the market will cost up to $40 million. Aside from the money, the biggest challenge is the intimate nature of what is being tested. The controlled environment of the lab and its MRI machines must be abandoned in favour of real-world situations. Excusing himself for the indelicacy,

27bn condoms predicted to be used in 2015

Omar explains that “you cannot get into the bedroom to make sure couples use the product before sex.” Omar’s voice is sincere when he describes his research, reminding me over and over of the injustice he and his colleagues want to address. “Men have always had control over the condom. Women have no say,” he says. “Our goal is just to help women.” The sex-toy condom and the invisible one couldn’t represent two more opposing visions of the future of safe sex. But they have one important thing in common: their starting point was thinking outside the box. Resnic is sure that the future will be even more diverse. “The era of there only being one rolled male condom is over,” he says. Instead, we will have a variety of devices that address the needs of everybody – male, female, straight, gay, wealthy, impoverished. It has only been in the past 50 years that people have gotten comfortable enough talking about sex to openly discuss condoms, he says. Hopefully it will not be as long before the rubber receives its long-awaited makeover. n Hannah Krakauer is a writer based in Seattle 19 January 2013 | NewScientist | 39

Many of our genes have no obvious relatives or evolutionary history. So where did they come from, wonders Helen Pilcher?

Gordon Wiebe

All alone

40 | NewScientist | 19 January 2013

N

OT having any family is tough. Often unappreciated and uncomfortably different, orphans have to fight to fit in and battle against the odds to realise their potential. Those who succeed, from Aristotle to Steve Jobs, sometimes change the world. Who would have thought that our DNA plays host to a similar cast of foundlings? When biologists began sequencing genomes, they discovered that up to a third of genes in each species seemed to have no parents or family of any kind. Nevertheless, some of these “orphan genes” are high achievers, and a few even seem have played a part in the evolution of the human brain. But where do they come from? With no obvious ancestry, it was as if these genes had appeared from nowhere, but that couldn’t be true. Everyone assumed that as we learned more, we would discover what had happened to their families. But we haven’t – quite the opposite, in fact. Ever since we discovered genes, biologists have been pondering their origins. At the dawn of life, the very first genes must have been thrown up by chance. But life almost certainly began in an RNA world, so back then, genes weren’t just blueprints for making enzymes that guide chemical reactions – they themselves were the enzymes. If random processes threw up a piece of RNA that could help make more copies of itself, natural selection would have kicked in straight away. As living cells evolved, though, things became much more complex. A gene became a piece of DNA coding for a protein. For a protein to be made, an RNA copy of the DNA has to be created. This cannot happen without “DNA switches”, which are actually just extra bits of DNA alongside the protein-coding bits saying “copy this DNA into RNA”. Next, the RNA has to get to the protein-making factories. In complex cells, this requires the presence of yet more extra sequences, which act as labels saying “export me” and “start making the protein from here”. The upshot is that the chances of random mutations turning a bit of junk DNA into a new gene seem infinitesimally small. As the French biologist François Jacob famously wrote 35 years ago, “the probability that a functional protein would appear de novo by random association of amino acids is practically zero”. Instead, back in the 1970s it was suggested that the accidental copying of genes can result in a single gene giving rise to a whole family of

genes, rather like the way animals branch into families of related species over time. It’s common for entire genes to be inadvertently duplicated. Spare copies are usually lost, but sometimes the duplicates come to share the function of the original gene between them, or one can diverge and take on a new function. Take the light-sensing pigments known as opsins. The various opsins in our eyes are not just related to each other, they are also related to the opsins found in all other animals, from jellyfish to insects. The thousands of different opsin genes found across the animal kingdom all evolved by duplication, starting with a single gene in a common ancestor living around 700 million years ago (see diagram, page 42). Most genes belong to similar families, and their ancestry can be traced back many millions of years. But when the yeast genome was sequenced around 15 years ago, it was discovered that around a third of yeast genes appeared to have no family. The term orphans (sometimes spelt ORFans) was used to describe individual genes, or small groups of very similar genes, with no known relatives. “If you see a gene and you can’t find a relative you get suspicious,” says Ken Weiss, who studies the evolution of complex traits at Penn State University. Some suggested orphans were the genetic equivalent of living fossils like the coelacanth, the last surviving members of an ancient family. Others thought they were nothing special, just normal genes whose family hadn’t been found yet. After all, the sequencing of entire genomes had only just begun.

So many orphans But as the genomes of more and more organisms were sequenced, genetic family reunions proved to be the exception rather than the rule. Orphan genes have since been found in every genome sequenced to date, from mosquito to man, roundworm to rat, and their numbers are still growing. The study of orphan genes is still in its infancy, and we know very little about most of them. Those we do know about are a mixed bag. Some are involved with the repair and organisation of DNA, or in controlling the activity of other genes. The insect orphan flightin, which encodes a muscular wing protein, evolved to aid flight. And in a study published last year, Manyuan Long of the University of Chicago and his team showed that two recently evolved young insect > 19 January 2013 | NewScientist | 41

42 | NewScientist | 19 January 2013

A family affair The genes for light-detecting pigments in animals all evolved by duplication from a single ancestral gene. It was thought that almost all genes arose this way and thus belonged to families

C-opsins - main light detector in vertebrates R-opsins - main light detector in arthropods RGR-opsins - assist light detection Placopsins - light detectors in placozoa Melatonin receptor - detects the hormone VERTEBRATES

MOLLUSCS & ARTHROPODS

JELLYFISH

PLACOZOA

SOURCE: FEUDA 2012

Curiously, orphan genes are often expressed in the testes – and in the brain. Lately, some have even dared speculate that orphan genes have contributed to the evolution of the biggest innovation of all, the human brain. In 2011, Long and his colleagues identified 198 orphan genes in humans, chimpanzees and orang-utans that are expressed in the prefrontal cortex, the region of the brain associated with advanced cognitive abilities. Of these, 54 were specific to humans. In evolutionary terms, the genes are young, less than 25 million years old, and their arrival seems to coincide with the expansion of this brain area in primates. “It suggests that these new genes are correlated with the evolution of the brain,” says Long. Critics argue that most genes, new or old, are somehow involved with the workings of the brain, and that correlation does not prove causation. But Long cites a recent animal study that lends credence to the theory. Expressing one of the human orphan genes, SRGAP2C, in the neurons of developing mice doesn’t make the animals’ brains grow bigger. But it does encourage the nerve cells to grow denser arrays of dendritic spines, the tiny protrusions that enable neurons to connect with their neighbours. Having more connections might increase computing power, he argues. So these recently evolved human genes may have helped shape the human brain. “I think we’ve underestimated orphan genes,” says geneticist Diethard Tautz of the Max-Planck Institute for Evolutionary Biology in Plön, Germany. But where did they come from? In 2003, Tautz and a colleague suggested that orphan genes are formed by duplication, but then evolve so rapidly that any similarity to the original is obliterated. And they did have evidence that seemed to support this idea. They showed that orphans in fruit flies evolve three times more quickly than non-orphans. Orphan genes were thus crowbarred into the old model of genes arising by duplication. Later studies, however, suggest this can only explain the origins of a minority of orphans. So while the process is clearly important, it’s not the whole story. “The idea seemed reasonable at the time,” says Tautz,

”The idea seemed reasonable at the time because the alternative was so unlikely”

700 million years ago

However improbable…

“because the alternative seemed so unlikely.” The alternative? The only other possibility was that genes really can evolve from scratch, from random stretches of non-coding DNA. This is the idea long dismissed as completely implausible, because the leap from noncoding DNA to a gene with a useful protein product was considered so huge as to be impossible. But nature hasn’t read the textbooks. A few years ago, evidence began to emerge of genes created “de novo” in yeast, rice, mice and fruit flies. Then in 2009, David Knowles and Aoife McLysaght of the University of Dublin in Ireland showed that three orphan genes in people had indeed been created from scratch. They found that DNA sequences nearly identical to the genes existed in several other primates but were non-coding, meaning the genes must have arisen sometime after the human-chimpanzee split. They also showed that the orphan genes are transcribed to RNA and then translated into protein in multiple tissues, though the functions of the genes are not known yet. In 2011, another team described a further 60 human orphan genes created from scratch. McLysaght thinks this might be an overestimate – she believes that de novo gene synthesis is a rare phenomenon.

SINGLE ANCESTRAL GENE

orphans help shape foraging behaviour in the fruit fly Drosophila. In corals, jellyfish and polyps, orphan genes guide the development of explosive stinging cells, sophisticated structures that launch toxin-filled capsules to stun prey. In the freshwater polyp Hydra, orphans guide the development of feeding tentacles around the organism’s mouth. And the polar cod’s orphan antifreeze gene enables it to survive life in the icy Arctic.

Some other researchers, however, are starting to think it may be surprisingly common. A study of 270 primate orphan genes, led by M. Mar Albà and Macarena Toll-Riera of the Municipal Foundation Institute for Medical Research in Barcelona, Spain, found that only a quarter could be explained by rapid evolution after duplication (Molecular Biology and Evolution, vol 26, p 603). Instead, around 60 per cent appeared to be new. “De novo evolution is clearly a strong force – constantly generating new genes over time,” says Tautz. “It seems possible that most orphan genes have evolved through de novo evolution.” But how can it be possible? Knowles and McLysaght showed that the orphan genes they found sit next to and slightly overlap existing, older genes, so the orphans might be able to “borrow” their switches. Similarly, Albà and Toll-Riera found that half of the 270 primate orphans had acquired sequences from the genes of “transposable elements”, genetic parasites that can jump around in the genome. Meanwhile, the ENCODE study of the human genome published earlier this year showed that our DNA is littered with millions of potentially useful short switching sequences, and that single switches can interact with many genes. All this suggests that it is relatively easy for non-coding DNA to acquire the switches needed for RNA copies of it to be made. Indeed, the ENCODE study found that as much as

Richard Herrmann/Minden Pictures/FLPA

80 per cent of DNA is copied into RNA at least occasionally. Some argue that all this RNA is functional, but another interpretation is that most of this activity is just noise, and that junk DNA is routinely transcribed into RNA.

Proto-genes If so, we are basically experimenting with thousands of potential new genes all the time – and Anne-Ruxandra Carvunis of the University of California, San Diego, has shown that this is indeed the case, at least in yeast. Last year, her team analysed 108,000 short, unknown but potentially proteincoding sequences in the yeast genome (Nature, vol 487, p 370). More than 1000 were interacting with the cell’s protein-making factory, suggesting that they were being converted to proteins. “These may just be the tip of the iceberg,” says Carvunis. Her findings suggest that the protein-making factories in yeast are constantly churning out new proteins, allowing them to be “tested”, and she suspects that same is happening in all complex organisms. In between non-coding DNA and fully fledged genes, Carvunis thinks there is a whole continuum of “proto-genes”. Most will code for proteins that are neutral or harmful, so there will be no selection and the vast majority of proto-genes will revert to noncoding DNA sooner or later. But a few protogenes that are neutral or maybe even helpful will sometimes persist, and start to gather

beneficial mutations. Over millions of years of natural selection, they can become a proper gene – and thus is an orphan born. All this helps explain why orphan genes are often expressed in the testis. In most cells, DNA is tightly packaged, which reduces the chances of RNA copies being made. In certain immature sperm cells, however, the structure is more open, making it easier for proto-genes to be copied into RNA. Over time, the gene may come to be expressed in other tissues and evolve new functions. New discoveries about the nature of proteins also make the idea of genes arising de novo seem far more plausible. It was once thought proteins must be folded into a delicate, precise 3D structure to work properly, but it now seems many exist in a state of intrinsic disorder, flitting through thousands of different possible conformations, all the while remaining perfectly functional. About half of human proteins have at least one long intrinsically disordered segment, while 10 per cent are disordered from beginning to end. Peter Tompa of the Flanders Institute of Biotechnology in Brussels, who studies intrinsically disordered proteins, suspects that

”Between non-coding DNA and fully fledged genes there could be a continuum of ‘proto-genes’ ”

Most of our genes have relatives in animals like jellyfish, but a surprising number are orphans

new orphan genes are likely to code for disordered proteins because they are easier to make than folded proteins. And disordered proteins often play a role in cell signalling and regulation. “I wouldn’t be surprised if orphan genes turn out to have regulatory functions,” says Tompa. Perhaps this helps explain why orphan genes can become essential very quickly. In 2010, Long’s team used RNA interference to switch off evolutionarily old and new genes in fruit flies. They found that new genes, including orphans, were just as likely to be essential for life as old genes (Science, vol 330, p 1682). “This goes against the textbooks, which say the genes encoding essential functions were created in ancient times,” says Long. We still have a lot to learn about orphan genes, but we are now starting to trace their ancestry. And it looks as if we couldn’t find the families of most orphans because they don’t really have families. The raw DNA from which they sprung can be traced, but as genes they are the first of their kind. In this sense, the term orphans may be a misnomer. Perhaps they ought to be renamed Pinnochio genes – non-genes carved by chance and natural selection into proper, “living” genes. n Helen Pilcher is a freelance science writer based in the UK 19 January 2013 | NewScientist | 43

Where in the world…?

Guillaume Pazat/Kameraphoto/Picturetank

The way we use maps is changing fast, says Kat Austen, so prepare to enter uncharted territory

44 | NewScientist | 19 January 2013

D

O YOU know where you are? You are no doubt aware of who and what is immediately next to you. You may also be able to peer further, to a street name, a river or a skyscraper looming above rooftops. Chances are, then, that you could find your location on a map. Without maps, our mental picture of our place in the world would be utterly different. Before printed maps became widespread, humans had a much narrower idea of their true surroundings, based instead on memory or verbal descriptions. Another upheaval in our understanding of the world through maps is now under way, thanks to advances in the digital realm. There’s a race on featuring some of the world’s biggest companies to chart the globe and all its happenings in exquisite detail, and many believe it’s just getting started. These digital mapping efforts promise more than just the virtual reproduction of physical space. For centuries, the centre of the world was the hub of a civilisation, like China or Jerusalem, then it was Greenwich. Now, it’s you. For the first time, we’re using maps that know where we are and which can be customised to our needs. This development is poised to transform our ideas about our surroundings and influence our decisions as we navigate through the world. But while there may be no dragons or sea monsters in this uncharted territory, there could be surprises and dangers ahead. Given the ubiquity of digital maps on computers and smartphones, it’s easy to forget that they didn’t exist until relatively recently. One of the first efforts to digitise maps was in 2001, when the UK’s Ordnance Survey published virtual versions of their paper products. A few years later, a group called OpenStreetMap announced plans to create a free virtual map of the world, intended to be built by volunteers in a similar way to Wikipedia entries. Yet digital maps only entered the mainstream after Google got involved in the mid-2000s. Google Local was launched in 2004, in which businesses’ details were listed alongside a small map. Within a year, Google Maps arrived, complete with functions to search the map and give directions. Soon digital maps began to underpin hundreds of smartphone apps. These developments were only the start. “We’re still in the dot-matrix-printer period of online maps, and it’s moving so quickly,” says mapping historian Jerry Brotton at Queen Mary, University of London. “We’re going to > 19 January 2013 | NewScientist | 45

“We’re in the dot-matrix printer period of online maps, and it’s moving so quickly ” databases, says Nigel Shadbolt, chairman of the Open Data Institute in London. In recent years, these stores have been opening up. “My feeling is that this is a public good in the same way that clean air and clean water is a public good,” he says. For example, when police forces started publishing their crime data by location online, various apps emerged to display it geographically, such as Crime Maps in the UK and Spot Crime in the US. These allow people to see maps showing crimes in their vicinity, from antisocial behaviour to murder. The data is often updated rapidly – Hampshire Constabulary in the UK upload theirs within 24 hours of it happening. Some groups are trying to synthesise all this information. City Dashboard from University College London’s Centre for Advanced Spatial Analysis, for example, provides online maps of eight major UK cities, showing live weather conditions, air pollution data from a UK government agency and CCTV images of particular streets. What’s more, some of the information added to digital maps has arguably never been charted in real-time before. For example, City Dashboard also displays indicators of local happiness, fed by data from a website called Mappiness that asks volunteers to log their mood throughout the day. Similarly, various researchers are building maps of sentiment by turning to Twitter. Many tweets are tagged by location, and by analysing the language used in updates, it is possible to infer a population’s mood or opinions and plot this on continually updated maps.

look back in 10 or 15 years’ time and go ‘Oh my god this is embarrassing’.” Recently, other technology giants have cottoned on to the vast financial potential of digital maps. Microsoft has developed Bing Maps, Nokia has an app called Here and provides maps for Amazon’s Kindle Fire, and last year Apple entered the fray. There’s big money to be made: by owning the map, companies can sell geographically relevant advertising, as well as charge businesses to be listed. They can also charge third-parties for using the maps within apps and websites.

Inner space

46 | NewScientist | 19 January 2013

Small-screen maps may shrink your mental world too

Baptiste FENOUIL/REA

Despite all this activity, much of the world remains digitally uncharted. The ocean is one such frontier. Google is mapping the Great Barrier Reef; Bing Maps features shipwrecks; and a project called OpenSeaMap is charting the ocean’s shipping lanes, buoys and other features. The most coveted territory, however, is closer to home: the indoors. A navigation aid for large buildings is more useful to most people than one for a remote corner of the globe – and, crucially, there’s more money to be made in a map of one small mall than one of an entire desert. Google Maps now features the annotated floor plans of around 10,000 buildings, while Bing Maps has more than 3300. The list includes public places such as airports, hospitals, train stations, universities and museums and, increasingly, large shops such as IKEA, Harrods and John Lewis in the UK, and Home Depot in the US. Like outdoor digital maps, viewing such floor plans on a smartphone provides smarter navigation than you would get with a traditional map. One place this might come in useful is in an airport, where existing static maps on signs can be confusing, says Manik Gupta, senior product manager at Google Maps. His company’s digital airport maps show where you are, and soon they hope to provide directions for getting to your gate. This is not the only way that we are being placed at the centre of the map. Digital maps can also carry many layers of information about the world immediately around us – be it live traffic data, approaching buses or the impending weather. And crucially, the elements we see can be customised according to our needs. A lot of this information was previously inaccessible to most people. Much of it was locked away in government or proprietary

Gaining such an enhanced awareness of our surroundings could influence our decisions as we navigate through the world. Imagine that you have just arrived in a new city. We have always had a vague awareness of crime levels in certain areas, but a detailed map is something more concrete on which to base decisions. Combine this with maps of house prices, restaurant reviews, local demographics, well-being and more, and it is bound to change our perception of where we choose to live or visit. This is not necessarily a welcome development for all – it could discourage investment where it is needed and entrench social deprivation in some areas. Having such apparently rich maps to hand also raises another unanticipated consequence – that we will trust them too much. Already, prominent errors have highlighted the perils of doing so. For example, Apple recently misplaced an Australian town on its iPhone map, a mistake which led to the map’s users becoming lost in the outback and having to be rescued by police. Ensuring accuracy is far from simple (see “Maps and MacGyver”, right). At the root of such problems is an important truth: no map presents reality; it is always an abstraction. “Maps are true for a certain approach,” says Pat Seed, a mapping historian at the University of California, Irvine. “There aren’t universal truths.” Map-makers have always made a series of choices about how reality is represented – and this curation can affect our perspective without us realising. There’s an analogy in printed maps: most world maps rely on

‘Unviersalis tabula iuxta Ptolemeum’, Mercator’s edition Ptolemy’s ‘Geographia’ 1578/bridgeman art library

Ever since the first maps, designers have shaped our world view

the Mercator projection, devised in 1569 by Gerardus Mercator. It amplifies the size of Europe and diminishes that of Africa significantly, making it more of an abstraction of geopolitical dominance than accurate geography. Yet it still shapes our mental image of the globe.

Hidden features The problem with many digital maps is that it is difficult to know how they have been curated – and who, what and where is left out. “These questions are often extremely hard to answer,” says Mark Graham, director of research at the Oxford Internet Institute at the University of Oxford. The map-making choices made by the likes of Google or Microsoft are often unclear, he says, and their underlying code and principles remain secret. What’s more, the interests of these companies may not always align with those of individuals hoping for an accurate map. By searching for local cafes or bars, for instance, it can sometimes be hard to tell if the results are a true depiction of all that’s out there, or a display of paid-for advertisements. The opportunity for commodification of online maps is endless – and obscured. Reassuringly, efforts to make digital maps more transparent have been gathering pace. At its launch in 2004, OpenStreetMap (OSM) couldn’t compete with the scale and detail of Google, since it relies upon user submissions. Since then, however, it has grown significantly, and is now the basis of many location-based apps. Many of its users claim that in some cities it is more accurate than Google. OSM’s open approach to editing offers people greater autonomy over the maps they use. “It allows people to go in and change what

maps and macgyver Making digital maps is far from easy. Underneath the surface, they are built from myriad sources, which can lead to errors. For their base maps, the likes of Google and Apple still heavily rely on traditional mapping organisations. For topographic information on many countries, Google Maps turned to Dutch mapping provider Tele Atlas, which in turn collates information from established bodies, such as the UK’s Ordnance Survey. Google wants to change that. For the last few years, it has been implementing a project called Ground Truth. A large part of this effort involves processing satellite and Street View imagery to build maps from scratch. Google engineers train algorithms with optical character recognition software to read signs – such as street names or “one way” warnings – so that roads are accurately labelled. They can also recognise company logos on shopfronts so that businesses on the map are up-to-date. Using software automation to map the world helps speed up the process, but it can come at a price. In 2010, for instance, Google accidentally renamed the Greek island of Samos after the 1980s TV character MacGyver. Google’s algorithms were scraping Wikipedia for geographical information, but a vandal had altered the online encyclopedia. The “island of MacGyver” wasn’t corrected for several days.

was otherwise dictated to them,” says Steve Coast, the organisation’s founder. Whether OSM can dislodge Google’s dominance is unclear, but its supporters argue that at least there is competition from an organisation whose priority is accuracy and transparency, not financial profit. Digital maps may end up influencing more than just our commercial decisions, though. As more and more of us rely on smartphone-based maps for navigation, this may affect our ability to build maps in our minds, says Georg Gartner, a cartographer at the Vienna University of Technology in Austria, and president of the International Cartographic Association. Gartner argues that reading maps on cellphones can affect our spatial cognition. Small screens mean that we view less of a map’s context at once. In one experiment, Gartner found that people who used a series of smaller maps to navigate through a city found it harder to orient themselves in relation to landmarks compared with those who used a larger map with more visible context. They also struggled to describe an accurate picture of their route. And, if you are on foot at least, digital maps can be less effective than paper maps at helping you navigate. Toru Ishikawa at the University of Tokyo, Japan, compared the navigation skills of digital and paper map users on unfamiliar streets. He found that those referring to their phones travelled more slowly, walked longer distances and were worse at working out their orientation than those using a paper map (Journal of Environmental Psychology, vol 28, p 74). When using paper maps, we have to make an effort to interpret our location. But without flexing these mental muscles we are in danger of becoming less able to hold maps in our heads. “A map on a mobile device or in a navigation system leads to less accurate mental maps and a lower ability to act in the real world,” says Gartner. Digital maps offer to enhance and optimise the world, giving us an even richer experience as we navigate through it. But equally, there is the risk that they could make us duller, less questioning and more unadventurous – providing a curated, virtually mediated experience that will make us more reliant on proprietary tools than ever before. The potential risks and rewards as we enter this digitally mapped terrain are high. If we stay informed, perhaps we won’t get lost. n Kat Austen is an opinion editor at New Scientist 19 January 2013 | NewScientist | 47

CULTURELAB

Laugh and the world laughs with you Could one of the world’s most popular cosmetic procedures really change lives, asks Michael Bond

THE idea that emotions and feelings are triggered by changes in the body, rather than the other way round, seems counter-intuitive. Yet this idea has been entertained by psychologists for more than a century. In 1890, the father of them all, William James, wrote: “Common-sense face into a smile or frown will says, we lose our fortune, are sorry induce feelings of happiness or and weep; we meet a bear, are sadness. Finzi, an American frightened and run; we are dermatological surgeon, is a insulted by a rival, are angry fundamentalist in the church of and strike… The more rational embodied emotion. He believes statement is that we feel sorry facial expressions are “the power because we cry, angry because we behind the throne”, the principal strike, afraid because we tremble.” driver of our moods and feelings. Recent research has put flesh More than that, he thinks he can on the bones of these musings. change people’s feeling of mental Neurobiologists such as Antonio well-being by manipulating what Damasio of the University of they can do with their face. And Southern California have for some years he has been doing demonstrated that emotions just that by injecting botox into begin with actions – rapidly increased heart rate, for example – “The debate about the regulation of emotions is and end with the perception of as lively as ever, and this is those actions – the sensation of a provocative contribution” fear or anger. Damasio calls this the “body loop”: the brain learns of the body’s response to change the corrugator, or “frowning”, via chemical and electric signals muscle of depressed patients to conveyed by the bloodstream prevent it from contracting. and nervous system. Thus feeling This, he reasons, interrupts the follows behaviour; the mind feedback loop to the brain that follows the body. causes their negative outlook and In The Face of Emotion, Eric thus improves their mood. Finzi explores how this plays out It sounds incredible. Finzi in facial expressions. There is no seems to be saying that people doubt these are integral to the with depression can cure way we embody and experience themselves just by looking emotions: simply forcing your happier, or by repressing their 48 | NewScientist | 19 January 2013

Thierry Du Bois/REPORTERS/eyevine

The Face of Emotion: How botox affects our mood and relationships by Eric Finzi, Palgrave Macmillan, £16.99/$27

ability to look sad. Yet he describes some striking success stories. One person who had had severe depression for 13 years felt so much better after botox that he decided not to take his Prozac. Another who had tried therapy and various antidepressants with no effect reported a “dramatic improvement” after Finzi’s work. Finzi mentions several clinical trials, such as one last year in the Journal of Psychiatric Research, that confirm his findings. Is this a solution to depression or is it merely cosmetic? Time and more research will tell. Finzi does acknowledge the treatment is no cure, and that the injections need repeating every few months to maintain the effect. He says his patients do not feel better simply because they look better – not all of them had pronounced frown lines before treatment (a contracting corrugator does not always leave wrinkles). Yet given the effect of social interaction on mood, it is possible that some of the improvement is due to those around the treated person reacting more positively to a brighter countenance.

People respond more positively to a smile, so turn that frown upside down

This is one of several questions that Finzi fails to address. He has a knack of glossing over or not recognising potential downsides. What are the effects of not being able to express sadness or anger? How might it affect the way we relate to others, beyond boosting our ability to bluff in poker? Some studies, not mentioned in the book, suggest that because botox impairs people’s capacity to mimic facial expressions, it can make them seem less trustworthy or likeable. None of this gets much of a look-in. It all sounds a bit too good to be true. Yet The Face of Emotion is well worth reading. The scientific debate about the regulation of the emotions is as lively as ever, and this is a provocative and insightful contribution. Some of the outcomes Finzi reports look remarkable, even if the mechanism is unclear. As one satisfied patient testifies after receiving botox to reduce his anger, “I don’t really understand how this is working, but my wife says keep it up.” ■

For more books and arts coverage and to add your comments, visit newscientist.com/culturelab

Radiant health We must fully understand the risks of radiation to make the right choices health risks from radiation. Gale is a doctor specialising in treating patients exposed to high doses of radiation, and Lax is a scientific writer. Touring through various scenarios, from nuclear accidents to irradiated food, they show how our inability to put risk into context can have serious consequences. They start with an account of an

Radiation: What it is, what you need to know by Robert Peter Gale and Eric Lax, Knopf, $26.95

CIGARETTE smokers have three times the amount of polonium-210 in their blood as nonsmokers. Some medical uses of radiation expose us to a higher dose in one go than smokers get in a year, yet many are happy to accept these radiation risks. Compare this with the global alarm following the Fukushima disaster in 2011. As Robert Peter Gale and Eric Lax tell us in Radiation, Californians reacted to the news by buying iodine tablets, which in the circumstances were “as useful as Californians buying raincoats to protect them from rain falling in Barcelona”. Humans are ill-equipped to deal with uncertainty, and we know too much about the uncertainties around data on

Heavenly introduction A Down to Earth Guide to the Cosmos by Mark Thompson, Bantam Press, £16.99 Reviewed by Marcus Chown

ONCE upon a time, when I was a professional astronomer, I enjoyed a stint at a big telescope in the southern hemisphere. During an observing break, I went outside with colleagues and, with

High anxiety: a little knowledge can do more harm than good

HAMILTON/REA

Reviewed by Gerry Thomas

incident in Goiania, Brazil. In 1987, radiotherapy equipment was stolen and the thieves, tempted by the alluring blue glow inside, dismantled it carelessly. Because they didn’t know how to handle and contain radiation many people were exposed to variable doses of caesium-137, some with fatal consequences. Mishandling is not the only danger that flows from a dearth of proper knowledge about radiation. Confusion over the risks to health, both on the part of the public and politicians, can lead to societal stress and

stagnation in energy policy. The book navigates this troublesome territory without bias. The authors summarise health risks associated with various non-nuclear options, suggesting that energy policy should take into account all the possible health risks of a given strategy. Surprisingly, one conclusion is that the fly ash from coal power stations actually generates more radiation than is emitted by a nuclear power plant. Gale and Lax aim to fill in the gaps in public understanding of all things nuclear, and they are adept at doing so. Throughout the book they present a host of interesting facts and figures in humorous and accessible prose, and their explanation of the biological effect of internal radiation is excellent. These days we can measure radiation incredibly accurately, but are not good at putting health risks from radiation into perspective with all of the other risks that threaten our health. This book does a good job at explaining radiation and what it does, both good and bad. Radiation is integral to our planet and its use will shape our future here. In Radiation, Gale and Lax help us understand how and why. n Gerry Thomas is a molecular pathologist at Imperial College London

the aid of a star map, we began searching the sky for the Large Magellanic Cloud. When we found it, we cringed with embarrassment: this satellite galaxy of our Milky Way was a huge smudge, about six times the apparent size of the moon. I use this example to illustrate how professional astronomers, reliant on software to steer their telescopes, can be poor at finding their way around the night sky. Despite knowing how stars work, they may have little clue how to locate them. Well, they could do a lot worse than arm themselves

with A Down to Earth Guide to the Cosmos. Mark Thompson, astronomer on the BBC’s The One Show and Stargazing Live, has written an admirably clear and concise guide to the wonders of the night sky, which will give anyone with a hankering to rise above the humdrum a toehold in the heavens. Thompson deals with the nuts and bolts of how to read

“Professional astronomers know how stars work, but may have little clue how to locate them”

a star map depending on your latitude and the time of year. He weaves in a clear history of astronomy and an overview of modern astrophysics – so when you have found the stars you are looking for, you know how they work. From black holes to brown dwarfs, Neptune to neutron stars, pulsars to the Pole Star, it’s all here. “The real beauty of astronomy,” says Thompson, “is that it is free and open to anyone.” This is a book to get people started, whether keen amateurs or clueless professionals. n 19 January 2013 | NewScientist | 49

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