3 November 2018, №3202 New Scientist (Australia)

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CONTENTS

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Volume 240 No 3202

This Week Automated lie detection to be tested at national borders 5

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On the cover

Leaders

Tel +61 404 237 198 Email [email protected] Recruitment sales manager Mike Black Key account manager Viren Vadgama US sales manager Jeanne Shapiro

Marketing

35 Brain tingles What’s behind the ASMR craze? 8

Head of marketing Lucy Dunwell David Hunt, Chloe Thompson

Ghost moons The hunt for Earth’s extra satellites

Web development Maria Moreno Garrido, Tom McQuillan, Amardeep Sian

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8

3

News 4

THIS WEEK Lie-detecting tech at border control. Brazil’s new president. Fracking quakes in the UK. Animal populations in decline

6

NEWS & TECHNOLOGY Crickets evolve to purr. Rigid light is weird state of matter. Ditch cannabis for memory boost. Forgotten famine. Earth may have ghost moons. Orangutans are great mothers. Battle tech tested. Lewis Carroll is helping physicists. Animal huddles improve microbiomes. Removing sun spots. Higgs boson may have stopped universe from collapsing. New species of early bird

World’s best mothers Why orangutans take the prize

28 Did we really find gravitational waves? Breakthrough physics result questioned Plus VR without a headset (45). Rigid light (6). Purring crickets (6). Extremely old water (38). Maths in Wonderland (10)

Questions over gravitational wave discovery need answers. Should lie-detecting tools be trusted?

17 IN BRIEF Where backbones evolved. CCTV search engine. Skin tans better with a day out of the sun. Humpback whales stop singing around ships

Analysis 22 INSIGHT What climate change is doing to tropical storms 24 COMMENT Scientists should lobby for a better Brexit. Venezuela’s cryptocurrency 25 ANALYSIS Trump is wrong about air pollution

Features 28 Did we really find gravitational waves? 2015’s breakthrough discovery is in doubt 35 Brain tingles Some videos can trigger a weird state of relaxation called ASMR. What’s going on? 38 First there was water Earth’s liquid could predate the planet 42 Leave those kids alone Sugata Mitra believes children should have the chance to teach themselves

Culture 44 Rise of technopower How to resist frontierless technology 45 No-helmet VR Will superblack paint create virtual reality 2.0? PLUS: this week’s cultural picks 46 Long road to Mars Creating a space epic takes grit and guts

Regulars 26 APERTURE Help, I’m in a black hole! 52 LETTERS Depression isn’t just one condition 55 50 YEARS AGO Early attempts at IVF 56 FEEDBACK Second moon rising 57 THE LAST WORD Dangerous current

3 November 2018 | NewScientist | 1

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THE news that gravitational waves had been detected reverberated beyond the halls of physics. Confirming a long-standing prediction of Einstein’s general theory of relativity, the discovery presaged a new era in cosmology. Then came the doubts. No experiment could reproduce the claimed signal, and theorists began to question whether Joseph Weber’s massive aluminium bars, set up at the University of Maryland, could really have been moved by ripples in space-time. The theory and experimental practice of gravitational-wave detection have advanced immeasurably since these events

of the summer of 1969, and few would bank on history repeating itself. Yet Weber’s debunked claim is a reminder of how bias and wishful thinking can easily colour the best of scientific minds. Now, as we report this week, questions have been raised about the quality of the analysis behind the LIGO collaboration’s celebrated 2015 gravitational wave detection (see page 28). The dissenting researchers are credible and their own analysis is peer-reviewed. It should not be dismissed out of hand. To be clear: few people doubt gravitational waves are out there or that LIGO is our best bet to find

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HUMANS are terrible at spotting liars, so it is no wonder that we have long sought help from technology. Now border forces are interested in a tool that uses artificial intelligence to detect liars (see page 5). It will be trialled at some land borders into the European Union between November and May. The hope is it could detect anyone

coming to a country with plans to commit a crime or stay longer than allowed. However, the technology isn’t good enough yet to be rolled out, as those running the project concede. Worryingly, past trends with the use of tech suggests this may not matter for many. Polygraph-based lie detector tests are a case in point. Despite

them. Its peerless instruments are the result of decades of expert development to shut out extraneous noise that would confound this delicate detection. But no scientific discovery should be beyond scrutiny – no matter how advanced the technology that made it, how big and expert the team behind it, or how good the internal checks and balances they employ. The Weber controversy, which simmered on until his death in 2000, had an upside: it spurred the development of superior detection technologies that underlie LIGO today. Robust, open debate is science’s lifeblood. ■

their accuracy rates being poor, they are still used around the world, including in some situations by police in the UK and the US. Another example is police use of face-recognition software, despite reports showing it makes a significant number of mistakes. The new tool will only be advisory and not make decisions on its own. But history suggests people will give its advice too much weight, trusting it when they shouldn’t. ■ 3 November 2018 | NewScientist | 3

THIS WEEK

Brazil’s climate blow

FERNANDO MAIA/EPA-EFE/REX/SHUTTERSTOCK

THE election of Jair Bolsonaro, Brazil’s far-right new president, looks likely to further weaken protections for the Amazon rainforest, making the goal of limiting global warming to less than 2°C even harder to achieve. Bolsonaro has set out few specific environmental policies, and his statements have sometimes been contradictory. But there is no doubt that he wants to make it much easier to clear the country’s rainforest for new farms, mines and roads. Because his party does not have a majority in Brazil’s National Congress, Bolsonaro cannot overturn laws that limit deforestation by landowners and that guarantee the land rights of indigenous peoples. This obstacle may not matter, though: if he slashes support for the agencies that enforce environmental laws, farmers and

Massive drop in animal numbers

Fracking quakes pause operations

fracking after some smaller quakes. Experts say it is normal for fracking to cause such “microquakes”, and

miners will be able to flout them with impunity. The Amazon rainforest is one of the richest and most diverse habitats on Earth, and it continues to remove huge amounts of carbon dioxide from the atmosphere each year despite ongoing deforestation. But research suggests it is soaking up much less than it used to, so the task of limiting future warming will get even tougher. The stance of other nations could be crucial. Some European countries have suggested that they will not buy agricultural products from nations or companies that continue to clear land. If the whole European Union adopted this position, it could have a major impact: the EU is one of the biggest importers of Brazilian soya and beef, the very products driving deforestation.

Low breastfeeding rates in England

that many quakes of this magnitude THE world’s wild vertebrate species have seen populations crash by 60 per

A RASH of recent earthquakes has

already occur naturally in the UK every

AS FEW as four in 10 mothers in

forced fracking operations in the UK

year, although they are too small to

England breastfeed their babies

cent on average since 1970, according

to be halted several times. All are linked to fracking for gas at a site in Lancashire, pictured below.

be felt by people on the surface. But

beyond the age of 6 weeks, according

to conservation group WWF. The charity’s Living Planet Report

there is a danger such quakes could

to figures published by Public Health

break the seal on the fracking site

England last week.

says that the driving force behind the

Regulations say work must be paused

borehole, allowing methane to leak

decline is rising human consumption

when fracking causes quakes of

out and add to global warming, says

The World Health Organization recommends that babies be breastfed

of resources. While climate change is a

magnitude 0.5 or greater. Since 22

geologist Stuart Haszeldine at the

exclusively for the first 6 months of

growing problem, the biggest threats

October, several quakes have been

life. But in many cases, women are

to animals, as well as plants, are their

large enough to require this, the

overexploitation and loss of habitat to

largest measuring 1.1. The extraction

University of Edinburgh, UK. Cuadrilla said checks showed that the well had not been compromised

agriculture, which together account

firm Cuadrilla also voluntarily paused

following the magnitude-1.1 quake.

for 75 per cent of extinctions since

Rates of breastfeeding for babies between 6 and 8 weeks old have been

1500. Only a quarter of Earth’s land

relatively stable in England for the last

is essentially free of the impacts of

four years, only varying by a couple of

human activities, and this area is

per cent each year, according to data

projected to shrink to a tenth by 2050. The report urges world leaders

collected by NHS England. That so few

to make “the most ambitious global

suggests that, in their current state,

agreement yet” to tackle the decline in wildlife when they meet at the UN

they are unrealistic for many women. Breastfeeding is strongly

Biodiversity Conference in November.

recommended for a range of health

“We have an opportunity to design a

reasons. Breastfed babies are at lower

co-exist sustainably with the wildlife we depend upon,” says Ken Norris of the Zoological Society of London, which contributed to the report. 4 | NewScientist | 3 November 2018

various reasons.

mothers are meeting the guidelines

REUTERS/PETER POWELL

new path forward that allows us to

unable to continue breastfeeding for

risk of cot death and allergies, and are less likely to develop diabetes or become overweight later in life. Breastfeeding also reduces a mother’s risk of breast and ovarian cancer.

For new stories every day, visit newscientist.com/news

AI to interrogate travellers Trial of automated lie-detector test set to begin at some EU borders, reports Douglas Heaven

OLI SCARFF/GETTY

What’s in your suitcase? If you open the suitcase and show me what is inside, will it confirm that your answers were true? These are just two of the questions that an automated lie-detection system will ask travellers during a six-month pilot starting this month at four border crossing points in Hungary, Latvia and Greece with countries outside the European Union. It will be coordinated by the Hungarian National Police. The lie detector uses artificial intelligence and is part of a new tool called iBorderCtrl, developed by a Europe-wide consortium. The pilot will involve actual travellers, who will be invited to use the system after they have passed through border control. It won’t affect their ability to travel. But the plan is that the system will interview stage of iBorderCtrl asks eventually be able to grant people you questions via a virtual border permission to cross a border by guard on your laptop or phone. automatically assessing a range When you give your answers, the of information, including official device’s camera films your face documents, biometric data and This video is then analysed by social media activity – as well as AI software that looks at 38 microthe truthfulness of responses to gestures to spot patterns, such as security questions. slight movements of an eyelid. The web-based tool is intended “If the AI system thinks you to make crossing into the EU are lying, the virtual border quicker and safer, and identify guard becomes more stern, anyone wishing to break laws changing its expressions” when entering a country, such as staying longer than allowed. Yet several independent experts Some say such gestures are contacted by New Scientist associated with lying, but the idea expressed strong reservations is controversial and has little about the idea, questioning evidence, says Bennett Kleinberg the accuracy of automated at University College London, who lie-detection systems in general. works on crime prediction and In principle, automating the isn’t associated with the project. detection of deceit makes sense, The system scores each as people are terrible at spotting response and if you pass the test – liars, barely better at identifying documents in order, answers them than chance, according to a deemed truthful – you will be meta-study in 2006. given a QR code that you can scan Instead of a human asking when you reach the border to be you questions at the border, the let through. If it thinks you are

lying, the virtual border guard becomes more stern, changing its expressions and manner. It will refer you to a human guard when you reach the border, who will have access to your iBorderCtrl report. The lie-detector component is adapted from an existing system created by some members of the team, and was tested recently in a small experiment with 30 people. The participants were asked a series of questions by the virtual border guard. Half the group was asked to tell the truth and the other half to lie. The software identified those lying with around 76 per cent accuracy, according to results the team recently presented at a conference. The team acknowledges that this isn’t high enough and plan to improve the system’s accuracy by training it on the much larger data set that will be obtained during the pilot. “We’re quite confident of bringing it up to the 85 per cent level,” says Keeley Crockett at Manchester Metropolitan

A virtual border guard could soon be asking the questions

University, UK, one of the team. However, this is still very low accuracy. Were the system to be rolled out across the whole EU, many millions of people could be flagged as liars each year. The key problem with training a lie-detection algorithm on people who have been told to lie is that genuine liars have different tics than people who are acting, says Maja Pantic at Imperial College London. “If you ask people to lie, they will do it differently and show very different behavioural cues than if they truly lie, knowing that they may go to jail or face serious consequences if caught,” she says. “This is a known problem in psychology.” Crockett says the team is aware of the pitfalls and the main point of the pilot is to identify and address them. It will also train the border guards using the tool to understand its limitations. ■ 3 November 2018 | NewScientist | 5

NEWS & TECHNOLOGY

Fast evolution of purring crickets IN WHAT appears to be a case of remarkably fast animal evolution, crickets on Hawaii have begun to purr. The discovery is the latest twist in a decades-long battle between crickets and a parasitic fly that is attracted by their songs. Male crickets normally use their wings to “sing” to attract a mate, but this makes Pacific field crickets (Teleogryllus oceanicus) on Hawaii easy targets for a parasite. This fly (Ormia ochracea) tracks down crickets by listening out for their songs. It then deposits maggots that burrow inside their host, killing it. In 1999, researchers noticed that this strong incentive to stop singing meant that crickets on the Hawaiian island of Kauai were evolving to stay silent. This was the result of a mutation that gave males unusually flat wings, preventing them from producing a sound. By 2003, silent males made up about 90 per cent of the population, making it one of the fastest cases of evolution ever recorded in the wild. Similar silencing has been detected on other Hawaiian

Rigid light is a strange new state of matter THERE’S a new state of matter — and it’s weird. It is made from light and is somewhere between a solid and a superfluid. It can’t be stirred, rotated or even pushed. “If you have some water in a pipe and you start pushing it, it will flow a little faster,” says Marzena Szyman ´ ska at University College London. “Whereas this fluid is so 6 | NewScientist | 3 November 2018

islands. In 2014, for example, researchers discovered that crickets on the island of Oahu have also evolved flat wings, but via a different genetic mutation. “It’s a really cool rapid convergent evolution story,” says Robin Tinghitella at the University of Denver in Colorado. But now, some crickets seem to be regaining their voice and singing in new ways to escape detection by the flies. Studying crickets on the island of Molokai,

The Pacific field cricket has evolved rapidly to evade parasites

rigid that even pushing it will not change its velocity.” The new state is made from “liquid

bucket and rotate the bucket, the fluid itself will remain stationary. But Szyman ´ ska and her colleagues

light”. This is a fluid consisting of light trapped in a material, in which each photon is coupled with another particle. These hybrid particles, called polaritons, can flow and interact with one another in a way that photons alone cannot. In the past decade or so, it has been shown that liquid light can become a superfluid, a fluid that flows with no viscosity or friction. Because of the lack of friction, superfluids cannot be stirred or rotated. If you put one in a

calculated that, in certain situations, liquid light takes things one step further: not only is rotation impossible, its flow also cannot be changed at all. They call this new phase of matter and light a rigid state.

E. DALE BRODER

Colin Barras

Tinghitella and her colleagues have discovered males using what she describes as a “cat-like purr”. Examining these crickets in the lab, the team found that females are attracted by this call (The American Naturalist, doi.org/ cwdr). However, it is probably too low in pitch for the parasitic flies to hear. The team doesn’t yet know when the Molokai crickets began to purr. Tinghitella says that all the males she has studied on this island either purr or are silent, so it is possible that purring evolved from a silent ancestor. Purring may be the ideal

The state arises because of how liquid light is created. Photons are

“The laser actually sets the properties of the liquid light from the outside, so they cannot be changed”

solution for the crickets of Hawaii and their parasite problem. Mute males find it difficult to attract a mate, so starting to purr might boost their chances of success. This depends on how effective the new sound is as a mating song. “I definitely think it is plausible the purring crickets can communicate with potential mates,” says Ann Hedrick at the University of California, Davis. “The experiments are convincing.” However, the lab studies also revealed that the purr is a bit messy, varying a lot in pitch, for instance. Typically, effective signals evolve to have little variation for the sake of clarity. “We’ve caught this trait so early that natural selection doesn’t seem to have done much to the signal yet,” says Tinghitella. By choosing to mate with those that purr in a specific way, female crickets may refine this new song in generations to come. “The females might whittle it down so that it’s more like a typical male song,” says Tinghitella. Alternatively, the females might learn to love the purr as it is now. It is possible that they become so accustomed to it that they stop finding the original song attractive. If this were to lead to purring crickets no longer breeding with non-purring ones, it could be a step towards the evolution of a new species. ■

always leaking out of the material trap, so they must be replaced using a laser. The team found that the laser actually sets the properties of the liquid light from the outside, so they cannot be changed (Nature Communications, doi.org/gfgbd4). It’s not yet clear what this strange rigid light could be used for, but it could one day find a role in optical communications, says David Snoke at the University of Pittsburgh in Pennsylvania. “Even if it’s not good for anything, it’s interesting because it’s different,” he says. “It really is a new phase of matter.” Leah Crane ■

For daily news stories, visit newscientist.com/news

A depiction of the impact of famine that hit India in the 1870s

Smoking a joint makes your memory hazy

for making people less mentally sharp, it is hard to know if the drug causes the problems reported or if users have a worse memory to begin with. The only definitive way to find out is a randomised trial in which some people who don’t normally smoke cannabis take it up for months, but this wouldn’t ever get past an ethics board. So Randi Schuster at Massachusetts General Hospital in Boston hit on the idea of a trial that asks existing users to stop and compares them with a control group who continue. Schuster’s team recruited 88 people in the US aged between 16 and 25 who used cannabis at least once a week. Two-thirds of them, chosen at random, were incentivised with cash to quit for a month, with regular urine tests to keep everyone honest. At the start of the trial and then once a week they took tests of memory. The quitters scored significantly better in these tasks in the first week, and stayed at that level for the rest of the month (Clinical Psychiatry, doi. org/cwd2). Those who continued using cannabis only improved their scores slightly over the month, probably because they were getting used to the tests, says Schuster. Brain-scanning studies have shown that regular cannabis users have lower amounts of a receptor in the brain that binds chemicals in the drug. This receptor is normally found at high levels in the hippocampus, part of the brain involved in memory, says Tom Freeman at the University of Bath, UK, who wasn’t involved in the study. “It makes sense that this is where we are going to see the impairments.” Brain scans have also shown that cannabis receptor levels return to normal within two or three days of quitting. Clare Wilson ■

© ILLUSTRATED LONDON NEWS LTD/MARY EVANS

CANNABIS use really does weaken your memory. People who gave up smoking the drug saw their cognitive abilities improve after just a week. Though cannabis has a reputation

Freak climate event that killed millions explained IT IS the forgotten famine. A Holocausts. He estimated that global drought in the 1870s led to 50 million people died. starvation in South America, Asia Now Singh and her colleagues, and Africa, but the event doesn’t including Davis, have examined even have a Wikipedia page. the drought in detail. The first At last we are shedding light step was getting weather data on its causes. The drought was “If we had a drought like triggered by a combination of this today, there would be climate events never seen before. devastating effects on While rare, this was entirely hunger and on poverty” natural, so could happen again. Between 1875 and 1878, severe drought ravaged India, China from a time before records were and parts of Africa and South kept. Fortunately, in 19th century America. The result was a famine India a network of rain gauges was that struck three continents. set up. For other places, like China, “It is one of the worst the researchers estimated rainfall humanitarian disasters in human from tree rings. history,” says Deepti Singh at Singh says the results suggested Washington State University. the events of the 1870s were The resulting famine was unusually severe. By looking at described by Mike Davis at the estimates of rainfall based on tree University of California, Riverside rings and other proxies, the team in his 2001 book Late Victorian estimated that the drought at this

time was the most severe in Asia for 800 years. The researchers identified several factors that may have helped trigger the catastrophe. The most obvious was a big El Niño from 1877 to 1878. During an El Niño, warm water spreads over the Pacific, releasing heat into the air. This affects weather across the world, bringing storms to some places and drought to others. But that’s not all. In 1877, a second climate cycle, the Indian Ocean Dipole, was active, which meant the western Indian Ocean was warmer than the east. This typically weakens India’s raingenerating monsoon. “It was the strongest Indian Ocean Dipole on record,” says Singh. Finally, there is evidence of unusual warmth in the Atlantic from 1877 to 1879. To check which of these events may have played a role in the drought, the team ran a climate model in two ways. One used global sea surface temperatures. The other used just Pacific temperatures, simulating the El Niño alone. They found they could only explain the drought using the global sea temperatures (Journal of Climate, doi.org/cwb7). The study has impressed climatologist Isla Simpson of the National Center for Atmospheric Research in Colorado. “It’s pretty unusual to be able to go into this much detail on an event that far back,” she says. This pattern of climate events was natural, beyond our control, and so could be repeated. The good news is the world is more resilient to droughts today, thanks to better crops and extensive trade, says Olivier Rubin at Roskilde University, Denmark. “If we had a drought like this today, there would be devastating effects on hunger, devastating effects on poverty,” he says. But while people would go hungry, it should be possible to avoid such a deadly famine. Michael Marshall ■ 3 November 2018 | NewScientist | 7

NEWS & TECHNOLOGY

The hunt for Earth’s ghost moons Lagrange points, never being pulled down to Earth or the moon. In 1951, astronomer Józef Witkowski predicted that cosmic dust that floats through space should collect at two particular Lagrange points, each about 400,000 kilometres from Earth and from the moon. Then, in 1961, astronomer Kazimierz Kordylewski took the first pictures that seemed to show bright spots near these areas and used them as evidence that the clouds existed. The collected dust clouds are named Kordylewski clouds after him. But because these clouds are

Leah Crane

EARTH may have a pair of “ghost moons”, translucent clouds of dust that orbit along with our moon. New pictures seem to show these clouds, which could be up to 100,000 kilometres across, in fresh detail, potentially ending the debate over whether they exist. But not everyone is convinced. The Earth-moon system has a set of five gravitational balance points, where the gravitational forces from Earth and the moon balance out. Objects can get trapped in these regions, called

so tenuous and dim, it has Society, doi.org/cwf9). been difficult to observe them They found lots of this definitively, and astronomers polarised light in the area have debated whether they really where we would expect one are there or just a theoretical idea. of the Kordylewski clouds to A Japanese spacecraft that flew be. Their observations have through the two Lagrange points similar patterns to those seen in the early 1990s seemed to in earlier, lower-quality images. settle the debate when it didn’t “It has been difficult to find a clear increase in dust observe them definitively, levels, suggesting no dust clouds and astronomers have are present. debated if they do exist” But now there has been a twist in the story. Gábor Horváth at Eötvös Loránd University in “We are sure that these clouds Hungary and his colleagues are there,” says Horváth. claim to have pictured one of Nevertheless, other the Kordylewski clouds in detail. astronomers aren’t convinced They took pictures of one of that these observations show any these ghostly satellites using an difference from the surrounding Earth-based telescope and filters areas. “Rather than a ‘smoking designed specifically to pick up gun’, this latest paper seems to be light that has been bounced more like the smell of gunsmoke,” around by dust grains (Monthly says Anthony Dobrovolskis at the Notices of the Royal Astronomical SETI Institute in California. ■

populations. While children do have a higher survival rate in many countries today, not all achieve the orangutan’s level of success. Counter-intuitively, the key factor to the high survival rate is that forests

ORANGUTANS have staggeringly low rates of infant mortality. They are better at keeping their offspring alive than people have been for most of human history. “We see this incredibly high survival

in South-East Asia are unproductive, and fruit availability is erratic, says van Noordwijk. To ensure they get enough food without travelling too far, orangutans are solitary. This reduces competition and aggression, and protects them against disease. They also spend more time in trees than other great apes, protecting them from predators. “Together the protection against predation and disease makes it possible to have this high survival,” says van Noordwijk.

that’s higher than any [non-human] mammal that we know of so far,” says Maria van Noordwijk at the University of Zurich in Switzerland. Orangutan infants are raised solely by their mothers. The high survival rate is linked to orangutans’ lifestyle, which is more solitary than other apes. But the factors that help explain the high rate – including a low birth rate – may actually make orangutans more vulnerable to a population crash. Van Noordwijk and her colleagues compiled data on births and infant survival from two populations of Sumatran orangutans and three of Bornean orangutans. There is also a third species, the Tapanuli orangutan described in 2017, but they haven’t been studied long 8 | NewScientist | 3 November 2018

PEDRO NARRA/NATUREPL.COM

Orangutan mothers may be best in world

enough to estimate survival rates. Infants had a very good chance of surviving. Overall, 91 per cent survived

Orangutans have better infant survival rates than some human populations–

until they were weaned – which in

couldn’t determine survival rates for males after weaning, as they roam and so are harder to track (Journal

orangutans sometimes doesn’t happen until the infant is 8 years old. What’s more, the researchers discovered that 94 per cent of weaned females made it to adulthood and gave birth themselves. The team

of Human Evolution, doi.org/cwfg). This is a better survival rate than for any other great ape. It is also better than in some human

However, their slow lifestyle puts them at risk. Humans are killing orangutans and logging is carving up their forest habitat. “It takes a very long time to recover from a crash,” says van Noordwijk. “It’s one infant at a time.” The crucial thing will be to protect the largest possible habitats. “Having large connected populations is the best way of making sure they’ll hang in there,” says van Noordwijk.

Michael Marshall ■

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NATO tests battle tech of the future

During Trident Juncture, Odin will be monitored from 500 kilometres away with the help of a high-speed radio connection. NATO is also testing a selfdriving land vehicle that carries a remote-controlled gun. The vehicle can select an appropriate route to take once an operator has chosen its destination. In the exercise, its weapon will be loaded with blanks, not live ammunition. The gun has a visual sensor that will be used to test the vehicle’s surveillance capabilities. “We’re thinking we can use it for defence in Norway,” says Kim Mathiassen at the Norwegian Defence Research Establishment.

own, robots that grab stored items for personnel and 3D printers that pump out spare parts. The autonomous boat, called Odin, is able to tow a minesweeping device. As it crosses a naval minefield, the device beams acoustic and magnetic signals into the water to detonate nearby mines. The boat can also deploy underwater autonomous vehicles to make closer inspections. Such a system would entirely remove humans from the mine-clearing process.

The autonomous vessel Odin can tow a minesweeping device

Lewis Carroll’s equation helps physicists

Germany has built on Dodgson’s work to help simplify the complex equations that arise when trying to calculate what happens when particles interact (arxiv.org/ abs/1810.06220).

prize-winning physicist Richard Feynman. One early way of deriving equations from these diagrams is known as the parametric representation, but it has lost favour owing to its apparent complexity.

CURIOUSER and curiouser! Particle physicists have the author of Alice’s Adventures in Wonderland to thank for helping to simplify their calculations. Lewis Carroll, the 19th-century

The hope is that it could result in speedier and more accurate computations, allowing physicists at places like the Large Hadron Collider near Geneva, Switzerland, to improve the design of their experiments.

To mathematicians, however, patterns in the resulting equations suggest it might be possible to dramatically simplify them. Golz’s work makes use of the

children’s author, was the pen name of mathematician Charles Lutwidge Dodgson. Now, Marcel Golz at the Humboldt University of Berlin in

Working out the probabilities of different particle interactions is commonly done using Feynman diagrams, named after the Nobel

Chris Baraniuk

FFI

IT IS the biggest NATO exercise since the end of the cold war, and it features self-driving vehicles and 3D printers. The exercise, named Trident Juncture 18, started last week in Norway and will go on for about a month. Around 50,000 people are taking part, along with 10,000 land vehicles and more than 200 aircraft and marine vessels. There are also a boat and a land vehicle that can manoeuvre all on their

10 | NewScientist | 3 November 2018

“The work could improve the design of experiments at places like the Large Hadron Collider”

“Border control is one possible application.” The project to create the vehicle initially followed a desire to automate aspects of reconnaissance and surveillance. New technology also features in the form of 3D printing, as a facility developed by Norwegian manufacturing firm Fieldmade will be tried out. It looks like a large shipping container, but houses 3D printers that can churn out spare parts for vehicles on demand. For Trident Juncture, it will print plastic parts, not metal ones, but it is possible for such parts to replace metal ones in some vehicles, depending on how much load they must bear. The operators of the facility will also link up with a similar system used by the US Marine Corps, to see how easily the two teams can share designs. Finally, Norwegian firm AutoStore is bringing an equipment storage and retrieval system to the exercise. It features a unit packed with compartments in which tools or spare parts are kept. Small robots whizz around and pick out whatever is needed. But there is a potential catch with this sort of technology, says Justin Bronk at the Royal United Services Institute in London. “The logistics chain is one of the most vulnerable to cyberattack,” he says. “Automation there could make that worse.” ■

Dodgson identity, a mathematical equivalence that Dodgson noted in an 1866 paper, to perform this exact sort of simplification. While much of the connecting mathematics was previously done by Francis Brown at the University of Oxford, who tutored Golz, the intellectual lineage can be traced all the way back to Dodgson. “It’s kind of a nice curiosity,” says Golz. “A nice conversation starter.” “I can say with confidence that these parametric techniques, applied to the right problems, are gamechanging,” says Brown. Gilead Amit ■

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Huddling makes vole gut more energy efficient

huddling on the microbiome, Dehua Wang at the Chinese Academy of Sciences in Beijing and his colleagues put voles in a room at 4°C. They placed some in a single cage so they could huddle together for warmth, while others were kept alone. After three weeks in these conditions, Wang and his colleagues extracted gut bacteria from both sets of voles. They used antibiotics to sterilise the guts of another 12 voles kept at 23°C, and then seeded six of them with “huddling” vole gut bacteria and the other six with “isolated” vole bacteria. They found those with huddling vole bacteria in their guts consumed 15 per cent less food and had a resting metabolic rate 20 per cent lower than those with bacteria in their guts from the isolated voles. The finding suggests that huddling in the cold triggers changes to the gut flora that slow down the voles’ metabolism. This might be useful given that food is often scarce in winter (Microbiome, doi.org/gdqk5m). Wang’s team found a greater variety of bacteria in the huddling vole microbiome. They also noticed a spike in the concentration of one particular group of bacteria, Lachnospiraceae. These can generate short-chain fatty acids by breaking down dietary fibre. Wang says these fatty acids can be absorbed into the body of the host animal, which could explain why voles with lots of these bacteria in their gut don’t need to eat as much food as normal. “This is the first time we have shown that huddling behaviour changes animals’ gut bacteria,” Wang says. Yvaine Ye ■

DAVID TROOD/GETTY

MANY small mammals huddle together to keep warm in winter. It now turns out that this behaviour also changes the composition of bacteria in the animals’ guts in a way that seems to slow their metabolism and help them conserve energy. To investigate the effect of

Rubbing off years of sun exposure Alice Klein

a cream based on aminolevulinic acid (British Journal of Dermatology, doi.org/cwc3). After aminolevulinic acid is applied to the skin, it is absorbed by sun spots and forms a chemical called protoporphyrin IX. People must keep the cream on for

BROWN spots on skin caused by long-term sun exposure can be removed using medicated creams, a process that may help prevent some skin cancer. While the skin pigment melanin can help screen us from “It’s a bit scary at first as some of the effects of the sun’s you get all these raised ultraviolet rays (see page 18), sores, and the itchiness long-term exposure can still lead drives you crazy” to brown or pink scaly marks on the skin, called actinic keratoses. Also known as sun spots, these 2 hours while sitting in sunlight, can go on to become cancerous. which triggers protoporphyrin IX In the past, sun spot removal was to release molecules called usually done by freezing them reactive oxygen species. These with liquid nitrogen, but the cause the cells in sun spots to die pain this caused meant that only and ultimately fall off. one or two spots could be treated The prescription cream is at a time. normally applied once and works Creams that remove dozens of quickly, says Stephen Shumack sun spots at once are a less painful at the University of Sydney. alternative. Now a study led by It does inflame the skin though. Janne Räsänen at the University “You look like you’ve had a bad of Tampere in Finland has sunburn for the first few days, highlighted the most effective – then the skin gets scabby and

crusted over and the sun spots peel off within a week,” he says. “The skin looks a lot better afterwards – it becomes very smooth,” says Shumack. Räsänen’s study, which took place in Finland, compared the effectiveness of two different creams when used by 69 adults. They were aged 49 to 92 and had an average of 11 sun spots each, although some had as many as 32. The cream with aminolevulinic acid was more effective, removing 80 per cent of a person’s actinic keratoses. The majority of the participants said using this cream was almost completely painless. The other cream the study looked at contained methyl aminolevulinate instead, and the team found it removed 74 per cent of the keratoses. In Australia, aminolevulinic acid does not fall under the government’s drug subsidy scheme, so many people use less expensive fluorouracil cream instead. This is also effective for removing sun spots over large areas, but must be used daily for about four weeks and causes more irritation, says Shumack. Rob Brazier, a retired farmer in the rural town of Jandowae in Australia, recently tried fluorouracil cream to treat the spots on his arms, face, ears and chest. “It’s a bit scary at first because you get all these raised sores where the cream is reacting and the itchiness drives you crazy,” he says. After a few weeks, Brazier’s sun spots started to scrape off when he washed. Five months later, he is pleased with the results. “My skin looks pretty good now.” In farming areas like Brazier’s, where high sun exposure has been a way of life, the use of such creams seems to be catching on. “Everyone you speak to knows someone who’s doing it. A lot of people here grew up the same way I did – you’d work out in the sun ploughing all day with no shirt on and often no hat, and you wouldn’t think anything of it.” ■ 3 November 2018 | NewScientist | 13

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Did Higgs bosons save the universe? disorganised or high-entropy state, simply because there are more such states than highly ordered ones. Sloan illustrates this point by imagining rolling a million dice: There’s only one way to get all sixes, but once you introduce one number that’s not a six, there are 5 million permutations, he says. One of the highest-entropy states is that of a black hole, but suggesting the pre-inflation universe was filled with black

THE Higgs boson may have stopped the early universe from collapsing into black holes. Shortly after the birth of the universe, all matter was still crammed into a tiny region. Then, a process called inflation took over, rapidly expanding space. Most cosmologists agree that this inflation happened, but it’s not clear how. David Sloan at the University of Oxford and George Ellis at the University of Cape Town in South Africa reason that the Higgs boson may offer an explanation. Inflation requires a particular kind of particle that permeates every point in space, and the only particle we have seen like this is the Higgs boson. According to Sloan and Ellis’s calculations, if the Higgs boson is actually the right kind of particle, it would solve an important sticking point in our understanding of inflation: what the universe must have been like just before it happened. They suggest that the pre-inflation universe, just micromoments after the big bang, probably started in a fairly

Fossil reopens debate over the first bird

dinosaur ancestors. However, over the past decade its first-bird status has been questioned following the discovery of similar winged dinosaurs in China. This led to a 2011 study that concluded Archaeopteryx was not

WE HAVE identified a new species of Archaeopteryx, the famous “first bird” – and it supports the idea that the extinct animal really is a transitional form between dinosaurs and their bird descendants.

technically an early bird after all. Now it’s all change again. Martin Kundrát at the University of Pavol Jozef Šafárik in Slovakia and his colleagues have studied a hithertounexamined Archaeopteryx fossil

Archaeopteryx was named in the 1860s. It had wings and feathers, but teeth instead of a beak, which helped make the case that birds evolved from

which they say overturns that idea. The fossil contains most of the skull, plus parts of the shoulders and left wing. It was found in the early

14 | NewScientist | 3 November 2018

Inflation saw the universe go from a speck to humongous rather fast

HENNING DALHOFF / SCIENCE PHOTO LIBRARY

Leah Crane

holes creates a problem. This is because black holes often clump together and wouldn’t lead to the smooth universe we see now, with matter equally spread out everywhere. For similar reasons, a single mega black hole wouldn’t be right either. “You’d have this one singularity and you wouldn’t be able to expand it into trees and birds and all the wonderful things we see in the universe,” says Sloan. While we still don’t fully understand the Higgs boson, one suggested property is useful to the work of Sloan and Ellis. The particle has an associated Higgs

1990s, reportedly in a quarry near Daiting, Germany, and ended up with a private collector. In 2009, palaeontologist Raimund Albersdörfer bought it and it is now at the Bavarian State Collection of Palaeontology and Geology in Munich, Germany. The team found subtle differences between its bones and teeth and those of other known fossils of Archaeopteryx. The researchers say

“It looks more likely that Archaeopteryx really is somewhere on the lineage towards recent birds”

field, and as this field strengthens, gravity weakens. Sloan and Ellis’s calculations show this would allow the problem of black holes in a pre-inflation universe to be avoided entirely. That’s because the Higgs field would have been stronger shortly after the big bang, so gravity would have been much weaker. This would keep matter from being crushed into black holes before inflation began to spread everything out (arxiv. org/abs/1810.06522). It is a big step beyond the standard model of particle physics, but it is plausible because of the ways we think gravity and the Higgs field interact now, says David Wands at the University of Portsmouth, UK. However, one downside of the idea that the Higgs played this role is that we may be unable to test it. “Inflation is so extravagant in the amount of space that it produces that we only get to see a tiny portion of the whole universe as inflated,” says Wands. “It is hard to test these ideas about what happens before inflation in the patch of the universe that we see.” Sloan believes we shouldn’t write off testing the idea yet. He says we may be able to see its effects in the areas of the observable cosmos that are most like the super-dense pre-inflation universe, such as just outside a black hole. ■

that the specimen is a new species, Archaeopteryx albersdoerferi. When they built a new family tree of birds and dinosaurs, they placed the new species of Archaeopteryx at the base of the bird (or avian) line. “It’s in an important position to tell us about the early evolution of avian dinosaurs,” says Kundrát (Historical Biology, doi.org/cwbs). “It looks more and more likely that Archaeopteryx really is somewhere on the lineage towards recent birds,” says Oliver Rauhut of the Bavarian State Collection of Palaeontology and Geology. Michael Marshall ■

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IN BRIEF AI can find people from descriptions

Bird breaths may show how dinosaurs ruled the planet

smooth, which Brocklehurst says may allow the lungs to slide as they move to pump air in and out while the animal swims. In contrast, rows of vertebrae and ribs jut

FINDING someone in a surveillance video could soon be as easy as googling them. Descriptions of a suspect or a missing person are usually given in terms of height, gender and clothing. But trying to find a short woman wearing a red jacket in a video, say, often requires scanning hours of footage manually. A new tool can do it automatically. The system, created by Hiren Galiyawala at Ahmedabad University in India and his colleagues, uses machine learning to match individuals in videos to their descriptions. It was trained on 110 videos. Given a video it has not seen and a physical description, it looks for people in each frame and works out their height. If several people are the same height, it uses gender and colour of clothing to narrow down the selection. In tests, the system found 28 out of 41 people (arxiv.org/abs/1810.05080).

into the ostrich lung cavity, leaving deep grooves in the MANY dinosaurs were swift and active animals, which

lung surface. With that much support, the lung walls can

is puzzling given that Earth’s atmosphere held less

be thinner, says Brocklehurst, allowing birds to transfer

oxygen back then. But they may have thrived in the

more of the oxygen they breathe in into their blood. When Brocklehurst and his colleagues used CT scans

challenging conditions due to efficient, bird-like lungs. Robert Brocklehurst at the University of Manchester, UK, and his colleagues compared dinosaur lungs both

to compare the lung cavities of modern birds and

with those of living crocodilians, which share a common

found that all the dinosaurs had vertebrae more similar

ancestor with dinosaurs, and with those of birds, which

in shape to those of birds than those of reptiles. This

descended from them. First, they compared the lung of an alligator and an

suggests dinosaur vertebrae jutted into the lung cavity

ostrich. They found that the alligator’s lung cavity is

doi.org/cv99).

crocodilians with those of 16 dinosaur species, they

as they do in living birds (Royal Society Open Science,

Pregnancy length linked to breast cancer A WOMAN’S risk of breast cancer is affected by how many children she has and the age when she has them – although exactly why is a mystery. Now it seems pregnancy duration may be key. Mads Melbye at the Statens Serum Institute in Denmark and his colleagues examined Danish and Norwegian registries on childbirth and cancer. They looked at long-term effects,

tracking breast cancer cases at least 10 years after pregnancy. Women whose pregnancies lasted 33 weeks or less saw their breast cancer risk drop by 2.4 per cent on average. If the pregnancies reached 34 weeks or more, this risk fell by 13.6 per cent (Nature Communications, doi.org/cwbn). The numbers did not change when Melbye and his team adjusted for socio-economic

status. They also found that the link between lower cancer risk and a pregnancy of 34 weeks or more occurred whether or not the pregnancy resulted in a live birth. Although breastfeeding has been shown to cut cancer risk after pregnancy, this finding suggests other factors are at work. Susan Gapstur at the American Cancer Society says genetics, alcohol consumption and diabetes may also play a part, alongside length of pregnancy.

Shipping puts a halt to whale songs WHALES stop singing when ships are nearby. Male humpback whales living around the Ogasawara Islands in Japan stopped or reduced their singing in response to low-frequency shipping noise. Koki Tsujii at the Ogasawara Whale Watching Association and colleagues used two underwater recorders to capture the animals’ song in a remote area where a passenger-cargo liner was the only large ship running. They found that fewer whales sang within 500 metres of the ship’s route than sang elsewhere. Whales within 1200 metres of the ship when it passed tended to temporarily reduce or stop their singing. There were 26 singers in total (PLoS One, doi.org/cv98). 3 November 2018 | NewScientist | 17

For new stories every day, visit newscientist.com/news

IN BRIEF A day in the shade builds up a tan SKIN seems to tan most when you spend every other day out of the sun. This also reduces DNA damage. Sunlight contains ultraviolet rays that can harm DNA and lead to premature ageing and skin cancer. To protect against this, skin produces melanin, a dark pigment that acts like a natural sunscreen. The pigment starts to form within hours of sunlight exposure and gives the skin a tanned look. Carmit Levy at Tel Aviv University in Israel and her colleagues

Exercise hormone may lead to drug to prevent memory loss A HORMONE released by bone during exercise boosts memory storage and retrieval in older mice. The protein it uses has now been identified, and could form the basis of a treatment for agerelated memory loss. As we get older, the gearwheels that keep our body functioning, such as hormone secretion and cell regeneration, turn at a slower rate. For instance, we make less of a bone-building hormone called osteocalcin as we age. In previous research, Eric Kandel and his colleagues at

Columbia University in New York found that mice with osteocalcin deficiency showed symptoms of memory loss. They have also tied this memory loss to a gene called RbAp48, whose activity increases in mice injected with osteocalcin. Now Kandel’s team has injected 16-month-old mice with osteocalcin. Within 48 hours, the expression of RbAp48 in the brains of these old mice had risen by 15 per cent. In tests, old mice given the injection appeared to have fewer memory problems than old mice

that had not received the shot. Digging deeper, the researchers found that RbAp48 controls the expression of a protein called GPR158, to which osteocalcin must bind to pass on its memoryboosting impact (Cell Reports, doi.org/cwbt). “It’s the first time we have shown the detailed pathway between RbAp48 and osteocalcin,” says Kandel. “In the future, it may be possible to develop a form of GPR158 that can be administered to help reverse age-related memory loss.”

measured how much melanin exposed to UV light every day, every second day or every third day. To their surprise, the mice that tanned the most were those exposed to UV every second day. The extra pigmentation the mice produced meant their skin also experienced the least DNA damage. The same result was seen for human skin samples (Molecular Cell, doi.org/cwbb). Together, the findings suggest that skin cells need 48 hours between sun exposure periods to build up their maximum defences, says Levy. Her team is now trying to work out the evolutionary reason behind the two-day melanin cycle. “It’s strange because ancient humans would have been exposed to sun most days, so we don’t know why

PLAINPICTURE/TROMP L’OEIL

it takes 48 hours to work,” she says.

18 | NewScientist | 3 November 2018

NOBUMICHI TAMURA

mice produced when they were

Liquid metal puts wheels in motion A SMALL drop of liquid metal pushed along by an electric current is enough to propel a wheeled robot. Larger, soft-bodied robots that can change their shape could use the technique to roll like tumbleweed through unfriendly terrain on rescue missions. First, Shi-Yang Tang at the University of Wollongong in Australia and his colleagues put a drop of liquid metal made mostly of gallium in a small, plastic wheel. They added two electrodes, one either side of the drop, on a platform that slides around the wheel as it turns. While the electrodes are switched on, the resulting voltage pushes the metal droplet towards one electrode. Like a hamster running in a wheel, the metal drop keeps moving forward as the tiny tyre turns. Because the drop changes the robot’s centre of gravity, it continues to roll (Advanced Materials, doi.org/ gff6ds). The system takes less than 0.4 seconds to reach a maximum speed of 5.5 centimetres a second. This rolling motion takes less power and can generate higher speeds than other methods of robot motion, says Tang.

Fish evolution soared in the shallows BACKBONES helped vertebrate animals conquer the oceans, then

our well-preserved fish fossils are

early history of the group has been

no more than 360 million years old. Now Lauren Sallan at the University of Pennsylvania and her

a bit of a mystery, but an analysis

colleagues have collated records of

suggests shallow waters were key. Vertebrates are thought to have

fish fossils from before this time.

begun to diversify about 480 million

the first jawless forms to sharks

years ago, splitting into groups

and bony fishes, originated in very

that would become jawless fish,

restricted shallow waters hugging

cartilaginous fish and a lineage

the coastline,” says Sallan. This suggests that the evolutionary events that helped

the land and the skies. Until now, the

including bony fish. This last group ultimately gave rise to amphibians, reptiles, birds and mammals. But our grasp of this split is hampered by the fact that most of

“We found that all vertebrates, from

fill the seas with fishes occurred in tidal areas and lagoons (Science, DOI: 10.1126/science.aar3689).

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INSIGHT HURRICANES

Kicking up storms Tropical storms are becoming more intense and less predictable – and there is little doubt remaining that we are to blame, says Michael Le Page HURRICANE Michael was a big one. Intensifying faster than expected, its 250-kilometres-perhour winds were just short of Category 5 strength, making it the fourth most powerful hurricane to hit the US mainland since records began. The building codes in the Florida panhandle, where Michael made landfall on 10 October, are designed to protect only against

JOE RAEDLE/GETTY

Mexico Beach, Florida, was largely wiped out by Hurricane Michael

22 | NewScientist | 3 November 2018

winds of 180 kilometres an hour. Most houses were built long before even these codes were introduced. In seaside towns such as Mexico Beach, below, the winds and storm surge left few buildings standing. Michael is just the latest in a series of extraordinary tropical storms around the world (see “Trails of destruction”, right). “It’s been pretty shocking,” says hurricane expert Jeff Masters of online information service Weather Underground.

These storms are not just stronger, as climate scientists have long predicted for a warming world. They are also forming and moving over regions far beyond their normal range, as well as producing more rainfall and higher surges, and strengthening more rapidly, giving us less warning of their arrival. “There are many reasons to be concerned,” says atmospheric scientist Adam Sobel at Columbia University, New York. “We are not as prepared as we should be.”

Tropical storms are fuelled by the evaporation of warm water from the ocean surface. Hurricane season peaks in the northern hemisphere from August through to October, when the oceans are at their warmest. There are relatively few hurricanes each year, a lot of variability from year to year and problems with our records – for instance, some storms may have been missed before satellite records began in the 1970s. For those reasons, there is still some

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debate about whether ocean warming through climate change is creating clear trends. But the evidence is growing. The number of storms with wind speeds of 200 km/h or more has doubled since 1980 and those with winds of 250 km/h and up have tripled. “Modelling and theory says we should expect to see the strongest hurricanes get stronger,” says Masters. “By gosh, we certainly have seen some very strong hurricanes the last two years.”

Worrying trends Modelling suggests these maximum wind speeds will rise still further as the world warms. If we don’t limit carbon emissions, by 2100 we could be seeing storms with speeds topping 370 km/h, says Timothy Hall at the NASA Goddard Institute for Space Studies in New York. That’s worse even than it sounds because a wind’s destructive power is proportional to its speed cubed. Flooding is often a storm’s most severe impact. A warmer atmosphere contains more moisture, meaning more rain – or snow – can fall when conditions are right. Each degree of warming could result in 5 to 2o per cent more rainfall, says Sobel, resulting in a greater risk of inland flooding when storms make landfall. A trend yet to be confirmed is that hurricanes also seem to be moving more slowly as the world warms, dumping more rain in one place. Hurricane Florence this year and Hurricane Harvey last year may be examples. Storm surges are certainly getting higher because of global warming: average sea level has already risen around 0.2 metres, and could rise another 3 metres by 2100. A storm surge’s size also depends on wind strength, the area of water it blows over and how long it blows for. Bigger, stronger and slower-moving storms might pile up higher surges on top of rising seas,

TRAILS OF DESTRUCTION Tropical storms have set a series of disturbing records over recent years – in wind speed, intensity and geographical range. OCTOBER 2018: Hurricane Leslie Kept its hurricane status until it was within 300 kilometres of Portugal. No hurricane had been recorded in this region of the Atlantic since modern weather records began.

OCTOBER 2017: Hurricane Ophelia Was literally off the charts used by the US National Hurricane Center, forming further to the north-east than any on record. With peak winds of more than 180 km/h, it weakened into an extratropical storm before striking Ireland, where it caused extensive damage. SEPTEMBER 2017: Hurricane Irma Maintained wind speeds of more than

SEPTEMBER 2018: Typhoon Jebi Its storm surge flooded Kansai airport, Japan’s third biggest, shutting it down for 17 days. The airport was supposedly built to withstand surges.

300 km/h for 37 hours, longer than

SEPTEMBER 2018: Hurricane Florence

hit New Orleans in 2005, for the title

Dumped a record amount of rain in the Carolinas and caused extensive flooding, just a month before Hurricane Michael hit Florida (see main story).

of costliest hurricane on record, it

SEPTEMBER 2018: Storm Zorba Caused extensive flooding and wind damage in Greece and Turkey. This was a peculiarly intense “medicane”, a sort of hybrid storm, with a hurricane-like eye, that forms when extratropical storms push cold air over the Mediterranean and the system starts deriving energy from the warmer waters below it. Medicanes remain rare, but a study last year concluded that the risk will double if warming continues unabated.

although this trend remains uncertain, says Sobel. The warming of the oceans also means that the region where storms can reach peak strength is expanding out from the tropics. In the northern hemisphere, it is migrating 50 kilometres northwards each decade. In the southern hemisphere, it is moving south. This raises the risk of places at higher latitudes, such as Europe, being hit by major storms. By the time storms get that far north or south, they may technically be extratropical storms, powered

any other storm, and left a trail of destruction across the Caribbean. AUGUST 2017: Hurricane Harvey Vying with Hurricane Katrina, which

dumped more rain on the US than any

Technology. The rate at which tropical storms can intensify rises exponentially as the maximum potential strength, which depends on ocean heat, goes up. “That’s very concerning because it doesn’t give people time to prepare,” says Masters. Forecasters won’t be able to help much: although weather models are now great at predicting the paths storms will take, they are much less adept at predicting changes in intensity. These are thought to depend on small-scale features of storms far beyond the power of models to capture. We are also unsure of the effects a warming world might have on typical storm tracks, or how many storms will form. Earlier models had suggested there would be fewer storms overall, with a

other hurricane, causing extensive flooding around Houston, Texas. FEBRUARY 2016: Cyclone Winston The strongest tropical storm on record in the southern hemisphere, with winds of over 280 km/h. It killed 44 people in Fiji. OCTOBER 2015: Hurricane Patricia A Pacific hurricane, it became the strongest tropical storm ever recorded in terms of wind speeds, increasing from 135 km/h to a peak of 345 km/h in just 24 hours. It was small in extent, however, weakening before hitting a sparsely populated part of Mexico.

by the temperature difference between warm and cold air masses. “But it doesn’t really matter much how it’s classified if it does a lot of damage,” says Masters. “This has major implications for the design of infrastructure.” Perhaps the most disturbing feature of Hurricane Michael was how it intensified rapidly just before landfall. Such storms are likely to become increasingly common as the planet warms, according to modelling done in 2016 by Kerry Emanuel at the Massachusetts Institute of

“The region where hurricanes reach their peak strength is expanding out from the tropics” greater number of strong ones, but some more recent models have started showing an overall rise in numbers. Either way, we need to adapt. The main reason why the costs of tropical storms have soared in recent decades is that ever more people are living in the danger zones. Countries should be discouraging development in places at risk, says Sobel. And if people insist on living in harm’s way, they should prepare for the worst. The photographs of places like Mexico Beach show both the immense destructive power of hurricanes, and that some buildings, like the nowiconic Sand Palace, can withstand it if they are designed to. While the devil is still in the detail, there seems to be no doubt that tropical storms are set to become ever more dangerous as the world warms – and besides limiting further warming, now is the time to prepare. “Is this the future?” says Masters. “I think it very well could be.” ■ 3 November 2018 | NewScientist | 23

COMMENT

Holding it together Europe’s scientific elite say a hard Brexit will damage science. They should use their clout to get a less bad deal for all, says Ehsan Masood WHEN 29 Nobel prizewinners and six Fields medallists last week conveyed the danger posed to science by Brexit in a letter to UK prime minister Theresa May and European Commission president Jean Claude Juncker, you can be sure they sat up and took notice. Such was the concern inside the UK government that science minister Sam Gyimah took to the radio to reiterate his commitment to finding ways for scientists to be able to work in Europe; and to replace funds that might be lost. This response didn’t satisfy some of the letter’s signatories, because it will always be second best to the research community’s desire to stay in the EU. But it was still an impressive display of science’s collective firepower, and scientists’ ability to persuade the government on a matter that is of vital importance to their interests. The unfolding tragedy of Brexit

will damage science, but it will be far worse for other parts of society. A hard Brexit will be a disaster for those who need medication from Europe. It will be catastrophic for those on the lowest incomes when prices rise. A hard Brexit also risks rocking the peace in Northern Ireland and rekindling the flames of independence in Scotland. By the government’s own estimates, crashing out of the EU poses a risk to public order. And yet, you won’t find government ministers in a rush to respond to these communities. There are no ministers taking to microphones promising to replace the close to €11 billion that the UK’s poorest regions will receive from the EU between 2014 and 2020. That is a more concerning problem than scientists losing access to EU projects. Top scientists are among our society’s

Petro dollars Venezuela’s cryptocurrency isn’t just about keeping the economy afloat, says Brett Scott VENEZUELA is caught in a triplepinch. Oil production is falling, hyperinflation is undermining its currency, the bolivar, and foreign reserves to pay for imports are dwindling. Against this backdrop, President Nicolás Maduro went on TV last month to encourage citizens to invest in the petro, a national cryptocurrency launched 24 | NewScientist | 3 November 2018

in February. Can it succeed where the bolivar has failed? Venezuela needs to raise US dollars, but is frozen out of international financial markets after defaulting on its loans. Its answer, it seems, is to mint petro tokens and sell them in exchange for foreign currency. Maduro claims they are like an “oil

voucher”, representing oil from a particular region. This way the petro, notionally backed by real resources and foreign reserves, can be linked to the bolivar, arresting its slide. The crypto community already has a reputation for harbouring opportunists. It is common practice for them to generate tokens, give them a catchy name, and then try to sell them for dollars. If anything, Maduro is just following a well-established

“The libertarian core of the crypto community has been riled by this statecontrolled cryptocurrency”

formula. Holding a petro seems not to give the holder the right to redeem it for either oil or oil revenues, which suggests Maduro’s link between the petro and oil exists in words alone. The libertarian core of the crypto community has been riled by this state-controlled cryptocurrency. But they are prone to seeing the world as a battle between two monolithic forces – states and markets – and they fail to recognise that not all states are equal. Countries like Venezuela occupy the lower rungs of the world’s geopolitical hierarchy. They are supposed to play nicely within the global

For more opinion articles, visit newscientist.com/opinion

Ehsan Masood was editor of Research Fortnight from 2009 to 2017. His latest book is The Great Invention: The story of GDP and the making and unmaking of the modern world

financial system and produce oil for the advanced nations. Maduro and former president Hugo Chavez have refused to play along. Post-colonial governments have long tried to achieve financial independence from neoimperialist powers, but doing so invites sanctions and attempts at regime change. Cryptocurrencies were explicitly intended to free the underdog from the influence of big banks. Venezuela is hoping the petro can make that promise a reality. ■ Brett Scott is author of The Heretic’s Guide to Global Finance: Hacking the future of money

ANALYSIS US air pollution

TED SOQUI/GETTY

more privileged groups. They have key jobs at the heart of government. They have seats in the House of Lords, and can be found at the top of universities and businesses. They have close links to media institutions. When they speak, policy-makers are compelled to listen and respond. Thanks to these relationships, the UK’s science budget was relatively protected throughout the years of austerity. As welfare benefits were cut and children’s centres closed, scientists saw a succession of new institutions come on stream. Both the Labour and Conservative parties are committed to yet further funding increases, taking the science budget from 1.7 per cent of GDP to at least 2.4 per cent inside a decade. The value to society of all of this is not in doubt, but after a succession of good years, now is the time for the scientific elite to start taking a longer view. They have both political power and intellectual heft. They should be using more of their access to argue on behalf of others whose lives could be destroyed by Brexit. ■

Why Trump’s ‘cleanest air’ boast is just wrong Chelsea Whyte

exposed to air pollution concentrations above WHO suggested level”. That statement is simply false, as was pointed out by John Walke, an attorney who once worked for the US Environmental Protection Agency (EPA) and is now director of the Clean Air, Climate & Clean Energy Program at lobby group the National Resources Defense Council. Contrary to the president’s claim, Walke tweeted, 45 US cities have PM2.5 levels above those suggested for healthy air, according to the WHO data. These include some of the country’s most populous cities like

THERE are places in the US where air quality is so poor that it can lead to serious health problems, but you wouldn’t know that if you took President Trump’s word for it. On 22 October, Donald Trump took to Twitter to declare that the US has “the cleanest air in the world – by far”. His tweet included a map based on data gathered by the World Health Organization, showing the global distribution of PM2.5 – air pollution consisting of particles less than 2.5 micrometres in diameter. These fine pollutants come from “The only countries with vehicle exhaust, power plants and more deaths linked to this the burning of wood or heating oil, as kind of pollution than the well as natural sources like wildfires US are China and India” and volcanic eruptions. They are small enough to penetrate deep into the lungs and aggravate respiratory Atlanta, Chicago and Los Angeles. problems like asthma. Long-term Whether wilfully or unintentionally, PM2.5 exposure has been linked to Trump has misinterpreted the WHO’s lung cancer and cardiovascular disease. map. When taken in bulk, air pollution The map Trump tweeted stems in the US may be lower than in from an April 2018 WHO report but other countries. But a country with included a label not present in the vastly varied land use like the US – original. It read: “91% of the world including urban areas, desert and population (none in the U.S.) are large nature reserves – cannot

be summed up by one number. It is true that, compared with many urban areas across the world, those in the US do have relatively clean air. Nevertheless, cities in Australia, Canada, Sweden and several others have it much better. Not only are plenty of people in the US exposed to pollution above the WHO recommended levels, but nearly 94,000 people in the US are thought to have died in 2016 as a result of PM2.5 pollution, according to the 2018 State of Global Air report, compiled by health researchers in North America. That puts the US in third place after China and India, which together account for more than half of the world’s deaths due to fine particulate matter. “There is no safe level of exposure to PM2.5 pollution, which is deadly well below the US standard of 12 or the WHO level of 10 micrograms per cubic metre,” Walke tweeted. And while Trump touts the greatness of US air quality, he is simultaneously overseeing the dismantling of environmental protections in favour of cost-saving measures for industry. He has got rid of the part of the Clean Air Act that places limits on cancer-causing pollutants, and the EPA is looking to reverse strict ozone standards brought in by the Obama administration. If that goes through, US cities will be plagued by yet more smog, further exacerbating PM2.5 pollution. ■ 3 November 2018 | NewScientist | 25

APERTURE

26 | NewScientist | 3 November 2018

Help, I’m in a black hole! A GLORIOUS simulation lets visitors experience what it might be like to be sucked into a black hole, but without becoming human spaghetti. The Distortions in Spacetime simulation was created by Marshmallow Laser Feast. The aim, says Barney Steel from the design studio, is “to take people out of their bodies and put them in a space where they feel like they’re floating”. The installation’s 10-square-metre room feels like deep space thanks to its completely mirrored surfaces. The only light source is a panoramic screen, so when this is black, the room becomes deeply dark. Images on the screen then take visitors on a journey into a black hole. Approaching the event horizon, shapes distort and colours intensify. Extreme lensing effects then transport viewers on a psychedelic ride towards a big squeeze.

DREW FORSYTH/MANCHESTER SCIENCE FESTIVAL

The simulation was commissioned by the Manchester Science Festival in the UK, where the installation recently sucked in its first victims. It was created with advice from Matthew Allen, an astrophysicist at Cardiff University, UK. Steel hopes to arrange more showings in the UK and elsewhere soon. Liz Else

Photographer Barney Steel Marshmallow Laser Feast

3 November 2018 | NewScientist | 27

WAVE GOODBYE? Doubts are being raised about 2015’s breakthrough gravitational wave discovery.

ENRICO SACCHETTI

Michael Brooks investigates

28 | NewScientist | 3 November 2018

T

HERE was never much doubt that we would observe gravitational waves sooner or later. This rhythmic squeezing and stretching of space and time is a natural consequence of one of science’s most well-established theories, Einstein’s general relativity. So when we built a machine capable of observing the waves, it seemed that it would be only a matter of time before a detection. In point of fact, it took two days. The Laser Interferometer Gravitational-Wave Observatory collaboration, better known as LIGO, switched on its upgraded detectors on 12 September 2015. Within 48 hours, it had made its first detection. It took a few months before the researchers were confident enough in the signal to announce a discovery. Headlines around the world soon heralded one of the greatest scientific breakthroughs of the past century. In 2017, a Nobel prize followed. Five other waves have since been spotted. Or have they? That’s the question asked by a group of physicists who have done their own analysis of the data. “We believe that LIGO has failed to make a convincing case for the detection of any gravitational wave event,” says Andrew Jackson, the group’s spokesperson. According to them, the breakthrough was nothing of the sort: it was all an illusion. The big news of that first sighting broke on 11 February 2016. In a press conference, senior members of the collaboration announced that their detectors had picked up the signature of

gravitational waves emitted as a pair of distant black holes spun into one another. The misgivings of Jackson’s group, based at the Niels Bohr Institute in Copenhagen, Denmark, began with this press conference. The researchers were surprised at the confident language with which the discovery was proclaimed and decided to inspect things more closely. Their claims are not vexatious, nor do they come from ill-informed troublemakers. Although the researchers don’t work on gravitational waves, they have expertise in signal analysis, and experience of working with large data sets such as the cosmic microwave background radiation, the afterglow of the big bang that is spread in a fine pattern across the sky. “These guys are credible scientists,” says Duncan Brown at Syracuse University in New York, a gravitational wave expert who recently left the LIGO collaboration. Gravitational waves are triggered by the collision of massive objects such as black holes or neutron stars. They travel for billions of years, alternately squeezing and stretching the space-time in their path. Spreading out in all directions, they get weaker as they go, but they can be detected on Earth with a sufficiently sensitive instrument. The LIGO collaboration built two such instruments, the Hanford detector in Washington state and the Livingston detector in Louisiana. A third, independent instrument called Virgo, located near Pisa, Italy, joined the others in 2017. These “interferometers” shoot lasers down two long tunnels, then reflect them back in such a way that the pulses should arrive at the same time. Passing gravitational waves will distort space-time, making one tunnel longer than the other, and throwing off the synchronisation. By the time the waves wash over Earth, they are extremely weak, and the sort of change in tunnel length we expect is equivalent to about a thousandth of the diameter of a proton. That is far smaller than the disturbances that come from background seismic tremors and even the natural thermal vibrations of the > 3 November 2018 | NewScientist | 29

EMBARRASSING NOISES In 2014, the operators of the BICEP2 telescope made an announcement so momentous there was talk of a Nobel prize. A year later however, far from making their way to Stockholm for the award ceremony, they were forced to admit they had been fooled by an embarrassing noise.

detector hardware. Noise is a huge problem in gravitational wave detections. Hence why there are detectors in different places. We know that gravitational waves travel at the speed of light, so any signal is only legitimate if it appears in all the detectors at the right time interval. Subtract that common signal, and what is left is residual noise unique to each detector at any moment, because its seismic vibrations and so on constantly vary. This is LIGO’s main ploy for extracting a gravitational wave signal from the noise. But when Jackson and his team looked at the data from the first detection, their doubts grew. At first, Jackson printed out graphs of the two raw signals and held them to a window, one on top of the other. He thought there was some correlation between the two. He and his team later got hold of the underlying data the LIGO researchers had published and did a calculation. They checked and checked again. But still they found that the residual noise in the Hanford and Livingston detectors had characteristics in common. “We came to a conclusion that was very disturbing,” says Jackson. “They didn’t separate signal from noise.” The Danish team wrote up their research and posted it online. After receiving no response from the LIGO collaboration, they submitted it to the Journal of Cosmology and Astroparticle Physics. The journal’s editor, Viatcheslav Mukhanov of the Ludwig Maximilian University in Munich, Germany, is a world-renowned cosmologist. The editorial and advisory boards include top physicists such as Martin Rees from the University of Cambridge, Joanna Dunkley at the University of Oxford and Andrei Linde

Situated at the South Pole, BICEP2 had been scanning the cosmic microwave background, the pattern of radiation left on the sky from light emitted soon after the big bang. The big announcement was that it had found that gravitational waves had affected the pattern in such a way that proved a core theory of cosmology. The theory in question was inflation, which says the universe went through a period of superfast growth right after the big bang. For almost four decades it had been unproven. Now, suddenly, inflation’s supporters were vindicated. Except awkward warnings emerged within weeks, suggesting that cosmic dust clouds had scattered the radiation in a way that fooled the BICEP2 researchers. In the end, the team’s estimate of the amount of dust present and the analysis of the kind of noise the dust would produce both proved to be flawed. Noise can hoodwink even the smartest. That is why, despite LIGO being a highly respected collaboration, there is good reason to take questions about its noise analysis seriously (see main story).

CUTTING THROUGH THE NOISE

SOURCE: arXiv 1706.04191

Amplitude

The gravitational wave observed in September 2015 is obscured by noise in the raw signal from LIGO’s Livingston detector. It is only visible in the cleaned-up plot, where irrelevant frequencies have been removed and the scale is magniied 100 times

0

5

10

15 Time (seconds)

30 | NewScientist | 3 November 2018

20

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of Stanford University in California. Mukhanov sent the paper for review by suitably qualified experts. Reviewers’ identities are routinely kept secret so they can comment freely on manuscripts, but these were people with a “high reputation”, says Mukhanov. “Nobody was able to point out a concrete mistake in the Danish analysis,” he says. “There is no mistake.” A storm in a teacup, still? General relativity is one of our most well-verified theories, after all, so there is every reason to think its prediction of gravitational waves is correct. We know LIGO should be sensitive enough to detect them. The instruments are finding the waves at exactly the right rate predicted by theory. So why worry about this noise?

Seek and ye shall find There’s a simple answer to that question. Physicists have made mistakes before, mistakes that have been exposed only by paying close attention to experimental noise (see “Embarrassing noises”, left). The first step to resolving the gravitational wave dispute is to ask how LIGO’s researchers know what to look for. The way they excavate signal from noise is to calculate what a signal should look like, then subtract it from the detected data. If the result looks like pure, residual noise, they mark it as a detection. Working out what a signal should look like involves solving Einstein’s equations of general relativity, which tell us how gravitational forces deform space-time. Or at least it would if we could do the maths. “We are unable to solve Einstein’s equations exactly for the case of two black holes merging,” says Neil Cornish at Montana State University, a senior figure among LIGO’s data analysts. Instead, the analysts use several methods to approximate the signals they expect to see. The first, known as the numerical method, involves cutting up space-time into chunks. Instead of solving the equations for a continuous blob of space, you solve them for a limited number of pieces. This is easier but still requires huge computing power, meaning it can’t be done for every possible source of gravitational waves. A more general approach, known as the analytic method, uses an approximation of Einstein’s equations to produce templates for gravitational wave signals that would be created by various sources, such as black holes with different masses. These take a fraction of a second to compute, but aren’t accurate enough to model the final merger of two black

DAVID RYDER/BLOOMBERG VIA GETTY IMAGES

To spy gravitational waves, LIGO’s detectors (pictured, page 28) need a quiet environment

holes. This endgame is modelled in an add-on calculation in which researchers tweak the parameters to fit the results of the initial analytic solution. This use of precalculated templates is a problem, Cornish concedes. “With a template search, you can only ever find what you’re looking for.” What’s more, there are some templates, such as those representing the waves created by certain types of supernovae explosions, that LIGO researchers can’t create. That’s why Cornish prefers the third method, which he helped develop. It involves building a model from what he calls wavelets. These are like tiny parts of a wave signal that can be assembled in various ways. You vary the number and shape of the parts until you find a combination that removes the signal from the noise. Because wavelet analysis makes no assumptions about what created the gravitational wave, it can make the most profound discoveries. The wavelets “allow us to detect the unknown unknowns”, says Cornish. The downside is that they tell us nothing about the physical attributes of the detected source. For that, we have to compare the constructed signal against the templates or the numerical analysis. The challenge with all three methods is that accurately removing the signal from the data requires you to know when to stop. In other words, you have to understand what the residual noise should look like. That is exceedingly tricky. You can forget running the detector in the absence of gravitational waves to get a background reading. The noise changes so much that there is no reliable background. Instead, LIGO relies on characterising the noise in the detectors, so

they know what it should look like at any given time. “A lot of what we do is modelling and studying the noise,” says Cornish. Jackson is suspicious of LIGO’s noise analysis. One of the problems is that there is no independent check on the collaboration’s results. That wasn’t so with the other standout physics discovery of recent years, the Higgs boson. The particle’s existence was confirmed by analysing multiple, well-controlled particle collisions in two different detectors at CERN near Geneva, Switzerland. Both detector teams kept their results from each other until the analysis was complete. By contrast, LIGO must work with single, uncontrollable, unrepeatable events. Although there are three detectors, they

“ T H E PA P E R ON THE FIRST DETECTION U S E D A D ATA P L O T T H AT WAS   M O R E ‘ I L L U S T R AT I V E ’ THAN PRECISE”

work almost as one instrument. And despite there being four data-analysis teams, they cannot work entirely separately, because part of the detection process involves checking that all the instruments saw the signal. It creates a situation in which each positive observation is an uncheckable conclusion. Outsiders have to trust that LIGO is doing its job properly.

Purely illustrative And there are legitimate questions about that trust. New Scientist has learned, for instance, that the collaboration decided to publish data plots that were not derived from actual analysis. The paper on the first detection in Physical Review Letters used a data plot that was more “illustrative” than precise, says Cornish. Some of the results presented in that paper were not found using analysis algorithms, but were done “by eye”. Brown, part of the LIGO collaboration at the time, explains this as an attempt to provide a visual aid. “It was hand-tuned for pedagogical purposes.” He says he regrets that the figure wasn’t labelled to point this out. This presentation of “hand-tuned” data in a peer-reviewed, scientific report like this is certainly unusual. New Scientist asked the editor who handled the paper, Robert Garisto, whether he was aware that the published data plots weren’t derived directly from LIGO’s data, but were “pedagogical” and done “by eye”, and whether the journal generally accepts illustrative figures. Garisto declined to comment. There were also questionable shortcuts in the data LIGO released for public use. The collaboration approximated the subtraction of the Livingston signal from the Hanford one, leaving correlations in the data – the very correlations Jackson noticed. There is now a note on the data release web page stating that the publicly available waveform “was not tuned to precisely remove the signal”. Whatever the shortcomings of the reporting and data release, Cornish insists that the actual analysis was done with processing tools that took years to develop and significant computing power to implement – and it worked perfectly. However, anyone outside the collaboration has to take his word for that. “It’s problematic: there’s not enough data to do the analysis independently,” says Jackson. “It looks like they’re being open, without being open at all.” Brown agrees there is a problem. “LIGO has taken great strides, and are moving towards open data and reproducible science,” he > 3 November 2018 | NewScientist | 31

Simultaneous signal There is other evidence to suggest that at least one of the later detections came from a gravitational wave. On 17 August 2017, the orbiting Fermi telescope saw a burst of electromagnetic radiation at the same time as the LIGO and Virgo detectors picked up a signal. Analysis of all the evidence suggests that both signals came from the brutal collision of two neutron stars. The double whammy makes LIGO’s detection seem unequivocal. Even here, though, the Danish group is dissenting. They point out that the collaboration initially

SAUL LOEB/AFP/GETTY IMAGES

says. “But I don’t think they’re quite there yet.” The Danish group’s independent checks, published in three peer-reviewed papers, found there was little evidence for the presence of gravitational waves in the September 2015 signal. On a scale from certain at 1 to definitely not there at 0, Jackson says the analysis puts the probability of the first detection being from an event involving black holes with the properties claimed by LIGO at 0.000004. That is roughly the same as the odds that your eventual cause of death will be a comet or asteroid strike – or, as Jackson puts it,“consistent with zero”. The probability of the signal being due to a merger of any sort of black holes is not huge either. Jackson and his colleagues calculate it as 0.008.

The first gravitational wave discovery was announced to the world on 11 February 2016

registered the event as a false alarm because it coincided with what’s known as a “glitch”. The detectors are plagued by these short, inexplicable bursts of noise, sometimes several every hour. They seem to be something to do with the hardware with which the interferometers are built, the suspension wires and seismic isolation devices. Cornish says that LIGO analysts eventually succeeded in removing the glitch and revealing the signal, but Jackson and his collaborators are again unconvinced by the methods used, and the fact there is no way to check them. What are we to make of all this? Nothing, apparently. “The Danish analysis is just

H O W T O C AT C H A WAV E Output from gravitational wave detectors is full of noise. Disentangling the signal requires decision– making – and poor ones could be disastrously misleading. The best weapon in the arsenal is known as a Fourier transform. This splits a signal into various frequency components and converts it into a power spectrum, which details how much of the signal’s power is contained in each of those components. This can be done with a window function, a mathematical tool that operates on a selected part

of the data. Whether or not to use one is at the heart of the disagreement over LIGO’s results (see main story). Andrew Jackson’s dissenting team at the Niels Bohr Institute in Denmark chose not to use a window function, a decision that LIGO’s Neil Cornish describes as a “basic mistake”. Jackson says they didn’t use one because it subtly alters the Fourier-transformed data in a way that can skew the results of subsequent processing. Even with the Fourier analysis done, judgements

32 | NewScientist | 3 November 2018

must be made about the noise in the detectors. Is it, for example, distributed in a predictable pattern equivalent to the bell-shaped Gaussian distribution? And does it vary over time or is it “stationary”? The appropriate techniques for processing the data are different depending on the answers to these questions, so reliably detecting gravitational waves depends on making the right assumptions. Jackson’s group says the decisions made during the LIGO analysis are opaque at best, and probably wrong.

wrong,” insists Cornish. “There were very basic mistakes.” Those “mistakes” boil down to decisions about how best to analyse the raw data (see “How to catch a wave”, below). Not everyone agrees the Danish choices were wrong. “I think their paper is a good one and it’s a shame that some of the LIGO team have been so churlish in response,” says Peter Coles, a cosmologist at Maynooth University in Ireland. Mukhanov concurs. “Right now, this is not the Danish group’s responsibility. The ball is in LIGO’s court,” he says. “There are questions that should be answered.” Brown thinks the Danish group’s analysis is wrong, but worth engaging with. And Cornish admits the scrutiny may not be a bad thing. He and his colleagues plan to put out a paper describing the detailed properties of the LIGO noise. “It’s the kind of paper we didn’t really want to write because it’s boring and we’ve got more exciting things to do.” But, he adds, it is important, and increased scrutiny and criticism may in the end be no bad thing. “You do have to understand your noise.” Coles himself doesn’t doubt that we have detected gravitational waves, but agrees with Jackson that this cannot be confirmed until independent scientists can check the raw data and the analysis tools. “In the spirit of open science, I think LIGO should release everything needed to reproduce their results.” Jackson is unconvinced that explanatory papers will ever materialise – the collaboration has promised them before, he says. “This LIGO episode continues to be the most shocking professional experience of my 55 years as a physicist,” he says. Not everyone would agree – but for a discovery of this magnitude, trust is everything. ■ Michael Brooks is a consultant for New Scientist

CIVILISATION Discover how our species built a global civilisation, how we gained and lost by doing so, and what might happen next. %X\\RXUFRS\IURPDOOJRRG PDJD]LQHUHWDLOHUV

Where did we come from? How did it all begin?

And where does belly-button fluff come from? Find the answers in our latest book. On sale now. Introduction by Professor Stephen Hawking

Brain tingles Videos of people folding towels or painting can trigger a mysterious state of relaxation in some people, including Michael Marshall. What’s going on?

MADS PERCH/GETTY

A

FEW years ago, I sat down in my home office and clicked through to a YouTube video. In it, a woman slowly folded towels on a table, while talking in a gentle whisper. Almost immediately, a warm, fuzzy tingle started around the nape of my neck, spreading across my shoulders and back. Within a minute, I was in a state of utter relaxation. The sensation lasted long after I stopped watching. I have experienced this calming tingle since I was a child, when my mother would stroke my back at bedtime. But I never mentioned it – it just seemed weird. Then a few years ago, I read an article about an internet subculture devoted to the “brain tingles” elicited by videos of people folding towels or The Joy of Painting – a TV show in which the host Bob Ross would produce an oil painting and quietly explain how he did it. Just reading the descriptions of these videos was enough to set off the sensation. Watching someone fold towels may seem tedious, but that clip has had more than 1,900,000 views. Clearly, I’m not alone. That got me wondering what was happening in my brain to elicit these feelings. Do they serve a purpose? And how many other people share my ability to easily find a state of blissful relaxation? >

“Brain tingles,” or ASMR, can send you into a state of bliss. But what is it?

3 November 2018 | NewScientist | 35

“A lot of people said ‘woah, I thought I was the only one who experienced this’ ” the phenomenon in which people’s senses merge, so they hear colour or see sound. “A friend approached me to ask if ASMR was related to synaesthesia,” says Barratt. “That was the first time I’d heard of it.” To start investigating, she and Davis asked people in online ASMR communities to fill out a questionnaire. From the 475 responses, they learned that episodes were pretty consistent: typically described as “a tingling sensation which originated towards the back of the scalp and progressed down the line of the spine and, in some cases, out towards the shoulders”. Four triggers were most popular, each favoured by more than half of respondents: whispering, personal attention, slow movements and “crisp sounds” like tapping fingernails. Barratt and Davis had established the basic reality of ASMR. Nevertheless, many questions remained unanswered – like what proportion of people experience it. The only estimate of prevalence comes from Giulia Poerio at the University of Sheffield, UK, who surveyed guests at a public neuroscience event in 2014. Of 91 36 | NewScientist | 3 November 2018

people, 53 had experienced ASMR, 15 hadn’t and 23 weren’t sure. It is clearly no niche sensation, and it seems far more common than synaesthesia, which is only experienced by 4.4 per cent of us. The responses also illustrated how misunderstood the phenomenon is. “A lot of people who said they had ASMR either thought everyone had, or they thought ‘whoa, I thought I was the only person who experienced it’,” says Poerio. There is also some information about who does and doesn’t experience it, thanks to two studies from 2017. Stephen Smith at the University of Winnipeg, Canada, and his colleagues asked 290 people with ASMR and 290 matched people without it to complete a test that measured the five main personality traits. People with ASMR had higher scores on openness-to-experience and neuroticism, and lower levels of conscientiousness, extroversion and agreeableness. The second study partly backed this up: people with ASMR scored high for openness-to-experience and low for conscientiousness. However, it isn’t clear what that means, says Daniel Bor at the University of Cambridge. “It’s quite possible that there is some underlying genetics that makes people both susceptible to ASMR and neurotic,” or the high openness-to-experience could simply reflect the people who try odd-sounding videos. It doesn’t help that nobody actually knows what ASMR is yet, although there are many ideas. Certainly, it resembles several known neurological states. Barratt and Davis looked for a link with synaesthesia, but found no significant difference in the frequency of synaesthesia among people who did and didn’t experience ASMR. They also compared it to “flow”: the mental state in which you concentrate fully on a task and it starts to feel almost automatic. Their survey revealed that people who experienced flow more readily also had more ASMR triggers. But anyone who has experienced ASMR knows it isn’t flow: it is fuzzy, almost trance-like. A more promising comparison is “frisson”. This sensation is similar to shivering, complete with goosebumps, but is triggered by an emotional experience like powerful music. It is sometimes called “musical chills”. People often reportedly confuse ASMR and frisson – but ASMR lacks the shivery, electric element. A 2016 review argued that ASMR is relaxing while frisson is arousing. Perhaps they are two ends of a spectrum.

KAI JABS/PLAINPICTURE

The phenomenon first came to people’s attention in 2007, in an online forum thread titled “weird sensation feels good”. Many names were suggested, notably “attentioninduced head orgasm” – a misnomer because the feeling is not as sudden or short-lived as an orgasm, and is distinct from sexual arousal. The term that stuck was coined in 2010 by cybersecurity expert Jennifer Allen: “autonomous sensory meridian response”, or ASMR. She wanted something that represented the key elements of the sensation, but that sounded scientific, so people wouldn’t be embarrassed to talk about it. It worked: those who experience the phenomenon are now a thriving online community. For instance, the ASMR subreddit has about 165,000 subscribers. The sensation has been popularised by pharmacologist Craig Richard of Shenandoah University in Virginia, who set up the website ASMR University. Science then began to catch up. The first studies of ASMR began to appear in 2014, with work by Emma Barratt and Nick Davis, both then at Swansea University, UK. Barratt was a master’s student interested in synaesthesia:

Slow movements, personal attention and whispering all seem to trigger ASMR – and perhaps not just in us

Whatever ASMR is, it has real effects. In a study published in June, Poerio and her colleagues monitored people’s heart rate and skin conductance – a measure of emotional arousal – while they watched ASMR videos. Everyone’s heart rates slowed, but the hearts of those who experience ASMR slowed more. The team also found that those with ASMR had increased skin conductance, indicating greater emotional arousal. “We expected to find a reduction,” says Poerio. “It might be to do with the fact ASMR is a complex emotional experience.” To really understand the phenomenon, however, we need to know what is going on in the brain during ASMR. In 2013, a student named Bryson Lochte at Dartmouth College in New Hampshire scanned the brains of people experiencing ASMR as part of his thesis. But the study went unpublished for years while Lochte studied medicine. In 2016, Smith and his colleagues used functional MRI to scan the brains of 11 people who experience ASMR and 11 who don’t, while they lay down doing nothing in particular. This activates brain regions called the default

Richard suggested something similar in 2014: that ASMR triggers neurological pathways involved in emotional bonding. In line with this, Lochte’s study found that the brain activation sparked by ASMR was similar to that seen in people and animals experiencing friendly behaviour. Poerio’s volunteers also reported greater feelings of social connection after ASMR. Maybe it is an intense version of the feeling we all get when loved ones tend to us – and videos can be a shortcut to it.

MONICA FECKE/GETTY

ROY TOFT/NATIONAL GEOGRAPHIC IMAGE COLLECTION

Genuine benefits

mode network, which is poorly understood but known to be involved in daydreaming, and the team found that some of the connections in this network were weaker and others stronger in people who experience ASMR. “The brain, at rest, is functioning differently in those with ASMR,” says co-author Jennifer Kornelsen at the University of Manitoba, Canada. She says this may help explain the sensation: the altered connectivity may reflect “a reduced ability or tendency to inhibit sensory-emotional experiences”. However, Bor is unconvinced. He says the participants weren’t matched by personality. “All the effects could be due to personality

differences,” he says. “It might not have anything to do with the ASMR trait.” Kornelsen says the team has since scanned the brains of people while they are experiencing ASMR, but the results aren’t yet published. However, in June, Lochte’s study finally appeared, with Richard as a co-author (BioImpacts, vol 8, p 295). It came out under a cloud: another author, William Kelley, also of Dartmouth College, was investigated for sexual misconduct, and resigned. Lochte and his colleagues used functional MRI to monitor brain activity in 10 ASMR-sensitive people as they watched videos that trigger the sensation. The scans showed significant activation in parts of the brain associated with reward and emotional arousal. Similar patterns are seen in frisson, suggesting the two sensations are indeed related. It is still unclear what all these findings mean, other than that the brain of someone who experiences ASMR seems to work differently. But why? It could be that this phenomenon evolved for an evolutionary purpose, says Davis, not least because it is so often triggered by personal attention. “If you look at great apes being groomed, I suspect they’re feeling something like ASMR,” he says. “They’re receiving close personal attention from another ape. I think it’s a rewarding state to be in.”

But others have doubts, arguing that the brain sometimes just does odd things. “Why should some visual stimulus cause head tingling?” asks Bor. “I can’t see any evolutionary purpose for that whatsoever.” Regardless of any explanation, the benefits seem genuine. Barratt “really didn’t expect ASMR to be therapeutically applicable”, but she and Davis found otherwise in 2014. “People showed this amazing elevation in mood during ASMR, but also that mood elevation persists for a few hours after,” says Davis. “It makes you happier when you’re doing it and it keeps you happy.” What’s more, those who were generally less happy showed a greater change. “People who are quite down are using ASMR to improve their mood,” says Davis. “People with chronic pain were using it, I don’t want to say to treat, but at least to distract from the pain.” For those who can, ASMR may be a simple way to relieve pain and stabilise mood. Poerio’s June study backs this up. A lower heart rate implies people are less stressed and more relaxed. When it comes to pain relief, it could be that the sensation of ASMR overpowers or distracts from the pain temporarily, or relaxation and improved mood might help with the pain. “It shows there’s a physiological benefit,” she says. Heart rates fell by 3.1 beats per minute during ASMR, which was similar to the effects of music-induced relaxation for people with cardiovascular disease. It is early days, but “our research would support this idea that potentially it could be used for therapeutic benefit”, she says. So even though I still don’t fully understand why I experience ASMR, I feel I was dealt a lucky hand. I have a mental trick that lets me pick up my mood if I’m feeling low or stressed. With the world going to hell in a handcart, that’s a handy thing to have. ■ Michael Marshall is a freelance writer based in Devon, UK 3 November 2018 | NewScientist | 37

From beyond the stars VINCE CAVATAIO/PLAINPICTURE

Could Earth’s water be older than Earth itself, asks geochemist Natalie Starkey

38 | NewScientist | 3 November 2018

M

ILTON KEYNES has the dubious distinction of being the town that supposedly has the most roundabouts in the UK. It is not the sort of place you might expect to be at the centre of a profound debate about Earth’s deep history. And yet, on its outskirts there is a lab housing a seemingly haphazard set of metal tubes, canisters, wires, cables and control boards, assembled into a piece of apparatus the size of a small car. My colleagues and I have used it to make the most precise measurements ever of rocks bearing traces of Earth’s earliest atmosphere. We believe that those measurements may put to bed a perplexing scientific mystery. This planet is a lush world of rivers, lakes and streams. But it shouldn’t be, according

to our traditional interpretation of Earth’s past. Our measurements at the Open University in Milton Keynes provide a strong indication that this explanation is past its sell-by date. The true story of how Earth got its water looks to be far stranger. If we are right, it means water, and potentially life that thrives in it, is probably far more widespread in the universe than we dared dream. To understand why the presence of so much water on Earth is so unlikely, we need to go back more than 4.6 billion years. The young sun is shining, and encircling it is a maelstrom of gas and dust that will clump into the planets. Any water exists as ice in interstellar space. If any of that ice found itself in the inner part of the solar system, where the rocky planets like

Earth will form, the heat and radiation split it into its constituent atoms of hydrogen and oxygen. This means the material that formed Earth shouldn’t have contained a speck of moisture. Let’s imagine that, somehow, interstellar water did survive the tumultuous starforming process to condense into oceans on Earth’s surface. It would then have the small matter of the impact that formed the moon to contend with. There are many details about how the moon formed that are contested. But our best understanding is that a Mars-sized object called Theia smashed into Earth about 4.5 billion years ago. The scientific consensus is that the impact was so epic that it vaporised our planet. Some of that cloud of gas coalesced into the moon and some >

3 November 2018 | NewScientist | 39

of it collapsed under its own gravity to remake idea that cosmic missiles delivered our water Earth. The conventional view was that water came from the Rosetta probe, which visited couldn’t have survived this. comet 67P/Churyumov-Gerasimenko in 2014 Yet here we are all the same. Free water may and found it had the “wrong type of water”. make up only a tiny proportion of the total All chemical elements, including those stuff on Earth, but there’s more than enough in water molecules, come in varieties called to go around: some 1.3 billion cubic kilometres isotopes that have different masses. The in the oceans alone (see diagram, below). proportions of the different isotopes of How can this be so? hydrogen in Earth’s water didn’t match those Many planetary scientists used to think that Earth must have received its water after the “We’ve sought the comets moon formed, by special delivery from space. that delivered Earth’s water The couriers could have been comets and asteroids, many of which formed far enough for years – but nothing fits” from the sun for water to survive. These space in the comet’s water. And this was one in a series rocks rained down on us in abundance during a period known as the late veneer, shortly after of failed matches. For decades, astronomers the moon’s formation. They brought with them have been hunting for a comet or asteroid that an inventory of precious metals, organic matter contains the right type of water together with the right mix of other elements we know were and volatile compounds, including water. We delivered in the late veneer. So far, nothing fits. can see evidence of this frenzied pelting if we That brings us to an impasse. Our story so look upwards: the surface of the moon is still far says that water shouldn’t have been pockmarked with the impact craters. present when Earth formed. It shouldn’t have There is no denying that Earth was bombarded in this way. But a strong blow to the survived the moon-forming impact. And it

Skin deep Crucial to Earth’s life though water is, its total volume is tiny compared with that of the planet

Earth 1.08 trillion km3

Oceans 1.34 billion km3

Groundwater 23.4 million km3

Swamps, lakes and rivers 190,000 km3

Water in atmosphere

seems our water can’t have been delivered by any comet or asteroid we know of. I never intended to get mixed up in this intractable mystery. The reason I did dates back to my PhD in the mid-2000s, when I was looking at rocks that originated from the boundary between Earth’s core and mantle. These samples were brought to the surface millions of years ago by upwellings of hot rock called mantle plumes. They only occur in rare places, like Baffin Island, Canada, and western Greenland in the case of my samples. I looked at tiny pockets of gas trapped in these rocks. Each pocket is a time capsule, allowing you to study an untouched sample of the young Earth’s atmosphere. A few years ago, I began working with Richard Greenwood at the Open University, who helped build that seemingly haphazard contraption. It is actually a precision mass spectrometer, which can separate and measure the isotopes in rock samples. Greenwood and his colleagues had been tinkering with it for years and had finally reached the point where they could make incredibly accurate measurements of oxygen isotopes in tiny samples of rock. We decided to compare the rock samples I studied during my PhD with moon rocks collected by the Apollo astronauts. We thought we could put to bed a long-running fracas over whether there is any isotopic difference between the moon and Earth. If the story we tell ourselves about our satellite’s formation is true, the isotopes from the two bodies should match. When Earth was vaporised during the giant impact, the isotopes of all elements should have been mixed up and then distributed evenly between the two. A long series of measurements of their isotopes had gone back and forth, first showing there was a difference, then there wasn’t, then there was again. It was a mess.

12,900 km3 SOURCE: USGS

Just like the moon Our more-precise analyses showed that there was a tiny yet clear difference between the isotopic composition of Earth and the moon – but that this could be accounted for by the shower of space rocks that bombarded our planet during the late veneer, so the two really could have started out the same. In trying to close the esoteric debate about Earth and the moon, we ended up shedding light on the mystery of our planet’s water. Based on our conclusions, we could tell that at least 70 per cent of the water on Earth today was here before the moon formed. Any less

MICHAEL CHRISTOPHER BROWN/MAGNUM PHOTOS

would have required there to have been more Funny seeing you here: it is a puzzle why impacts from space to deliver the rest of the Earth has any water water. Yet if this were so, we would have expected to see a larger difference between the isotopic compositions than we did. But hang on: haven’t we already said it is impossible for Earth’s water to have been here before the moon formed? Unlikely as it seems, some recent studies find that it might have been possible to hang on to our life-giving liquid through such a catastrophe. For example, a computer simulation of the vapour cloud, developed in 2015 by Robin Canup at the Southwest Research Institute in Texas, shows that it could have had enough gravity to cling on to the vaporised water. However, water first had to clear another hurdle: surviving the high temperatures of Earth before the moon-forming impact. This was the Hadean, a geological aeon named after hell because it was so hot. It sounds like a tough environment for water to endure. But some now think that any water our planet contained could have been locked inside now at the Harvard-Smithsonian Center for minerals deep in the mantle. Others say that Astrophysics, set up a simulation of the early Earth had cooled enough that a crust of rock solar system to investigate whether there could have formed over the molten surface, were any parts of the disc of gas and dust that sealing in water. formed around the young sun that might have There is an even weirder twist. Not only been able to manufacture water with excess did some of our water at least apparently deuterium – perhaps places where there was survive the infernal conditions of Earth’s lots of radiation. They couldn’t find any. early years and the moon-forming impact, That brings us to the surprising conclusion it might be even older than our planet that our planet’s water isn’t just older than itself. This conclusion comes from observations the moon. It must have come from interstellar of hydrogen and its sister isotope deuterium space, which means it is older than the sun in the water inside comets, asteroids, planets and the space between stars. Interstellar “In this radical story, our space has traces of water with a high ratio of rivers are filled with water deuterium to hydrogen. This is reflective of the environment. Interstellar space is cold that is older than the sun” and continuously bombarded by high-energy cosmic rays, producing conditions that favour itself. It is hard to fathom how it survived the inclusion of deuterium in water ice. entry into the solar system. But once you have We have also discovered that all the eliminated the impossible, it forces you to objects – comets, asteroids, planets – in the this conclusion. Cleeves suggests, drawing on solar system also have large amounts of other simulations, that there was probably a deuterium in their water. That is odd. If this short window of opportunity – after the sun water were originally interstellar, it must have had cooled enough, but before the planets somehow made its way into the inner solar formed – for interstellar water ice to sneak system during its early years. As the water into the solar system, raining down as the arrived, the young sun’s extreme radiation planets were beginning to form. should have broken it into its constituent All this adds up to a radically new story for atoms. When they recombined to form water how Earth got its water, one in which our that eventually ended up on the planets, planet’s rivers and oceans are filled with liquid more of the regular hydrogen should have that came from the void between the stars. been picked up than we actually see. It was Strange as it seems, I am confident this is the another mystery. best explanation of the evidence we have. A few years ago, a team led by Ilse Cleeves, This has wide-ranging implications,

including for the search for life beyond our solar system. If interstellar water is preserved on Earth, despite what we thought were incredible odds, it could be common in star systems across the universe. We believe all planets ultimately form from the same range of materials that collect around young stars. So if interstellar water survived here, then there is every chance that this life-fostering ingredient is widely available. Astronomers using NASA’s Spitzer space telescope have detected water in the discs around the young stars DR Tau and AS 205A, more than 350 light years from Earth. Water exists in their inner disc regions, the hottest zones close to the stars. These discs are yet to have formed planets, but this is evidence that water is available to newly forming planets from the early stages of a star’s history. True, it is not enough for water to have survived the first few million years of a star system’s life. It also has to cling to a planet during its chaotic early years. In the search for potentially life-sustaining exoplanets, those that were bombarded throughout their early years by comets and asteroids are usually discounted, the thinking being that large impacts would drive off any water. But as we showed, that too needs a rethink. Right now, the evidence suggests watery planets are common throughout the universe. ■ Natalie Starkey is a geochemist at the Open University and author of Catching Stardust, published by Bloomsbury Sigma 3 November 2018 | NewScientist | 41

INTERVIEW

Hey, teacher! Leave those kids alone In a Delhi slum two decades ago, Sugata Mitra discovered that a computer with an internet connection was enough to harness children’s curiosity and capacity to learn. We should learn the lesson, he tells Bob Holmes

I

N 1999, an inquisitive physicist named Sugata Mitra installed a computer in a slum in New Delhi, India, and then walked away. Local children congregated and began trying to use the unfamiliar device. When Mitra returned a few days later, they had already taught themselves to surf the internet. Mitra is now a professor of educational technology at Newcastle University in the UK. In the decades since the “hole in the wall” experiment, he has found that groups of children aged 8 to 12, left alone with the internet, can teach themselves even technical subjects such as evolutionary biology to a level several years ahead of their school age. In 2013, he won a $1 million TED prize to help his work.

How can children learn on their own, without guidance?

But are the children really learning, or just repeating phrases they don’t really understand?

The learning I’m talking about appears spontaneously in response to a query, which may be posed by an adult, or by the children themselves. I need the internet to be available on large, publicly visible screens in a safe space. I need to have mixed groups of children – boys and girls of different ages together, not each child on a different computer. Then I need to remove all supervision. We have got to keep the adults away. Everybody says, who taught them? How clever they are! But this doesn’t have anything to do with cleverness or teaching. It has to do with a hive-like mind with a common desire.

I could give them questions on quantum mechanics, and they would come back, not with the understanding that a physicist like me would have, but with a child’s understanding. I teased 9-year-olds by saying something could be in two places at the same time. They said no, if you have a pencil, it is here when you put it here and there when you put it there. I said there are some things that can be here and there at the same time – then I left. They came back with quantum entanglement, and said it means that the two particles know about each other, but we don’t know how those particles know.

PHILIPPE TARBOURIECH

Children in India worked together to teach themselves when provided with a “hole in the wall” computer

42 | NewScientist | 3 November 2018

Can children discriminate between good and bad information on the internet? Many adults have trouble with this.

The children get as confused as you and I. However, when they work in groups, they can detect extreme points of view and avoid those. Working in groups is key: the hive mind is more discriminating and less gullible than an individual in front of the screen. If I show kids a picture of the Colosseum in Rome and ask “what’s that building? And why is it broken?”, they come back with a lot of information about the Roman Empire. But now I go on to ask “how do we know what you said is true?” They start by saying that every website says so, which is good, but then they start going deeper, toward understanding historical evidence.

Sugata Mitra believes knowledge should be learned, not taught

make the information infrastructure answer a question just in time, when we need it to. This is as opposed to the old system, which is to teach the child everything we think they need, just in case. Does that mean I can go through life without knowing what the solar system is? That’s a horrifying thought. So perhaps we can agree on the big questions that children should engage with at various ages, then give teachers the liberty to pose the questions as they wish. Should we allow internet access during exams, then?

I think we should. But then we have a problem: who is going to evaluate the answer, and how? I don’t know yet – that’s what I’m working on now. But for example, when you are learning

“You just don’t need teachers telling children things they can look up on their own” to play an instrument, the exam is to play the instrument, and judges assess how good you are. Maybe we should move toward that kind of assessment in an internet-assisted world.

MURDO MACLEOD

If knowledge is in the cloud, not our heads, what happens if the internet fails?

Is this method effective even for very young children?

You can push it down to the point where the child is beginning to read, which might be age 4 or 5. And it accelerates reading development. With the TED prize, I set up labs in seven schools – five in India and two in England. We have got all the data now, and there is a definite, measurable improvement in reading comprehension over and above what would be expected. What role does this leave for teachers, and what do they think of your approach?

It’s not that you don’t need a teacher. You just don’t need the teacher to tell children things they could look up for themselves. You need the teacher to ask them questions that make

them sit up and wonder. My teacher friends tell me it is harder than preparing for a lesson where they just read out facts. In the 20 years I’ve been doing this work, the opinion of teachers has changed dramatically – from saying this is rubbish to saying, isn’t what you say obvious? But isn’t there a set of basic knowledge that needs to be learned by every child for them to get by in society?

I’m very glad that you said needs to be learned, not needs to be taught. All my work is about making that distinction. My answer is yes, but I’m not able to define that basic set very well. How much should I keep in my head, and how much should I rely on the internet? I tend toward thinking that we should know how to

If the internet goes down, we will live very uninformed. But that doesn’t mean that we should learn how to live without the internet – no more than we should learn how to tell the time of day without looking at a watch, just in case watches disappear. If I don’t have a watch, I won’t be able to tell the time. Sorry. You have faced scepticism because you haven’t published much comparative data in top-tier journals. What has stopped you?

I find it hard to publish – I get one rejection after another. I’m not from the social sciences. In the natural sciences, if results are unexpected, others repeat the experiment and report whether they got the same results. In the social sciences, people just seem to point at the holes in your work, but nobody ever says they repeated the experiment and got something else. So I have a humble request to social scientists: replicate my work and see if you get the same results. ■ Bob Holmes is a consultant for New Scientist 3 November 2018 | NewScientist | 43

CULTURE

The rise of technopower

MYRIAM ABDELAZIZ/REDUX/EYEVINE

How do we tackle forces that transcend frontiers? Ben Collyer explores

Nervous States: How feeling took over the world by William Davies, Jonathan Cape The Death of the Gods: The new global power grab by Carl Miller, William Heinemann

IN 2013, few outside Russia had heard of Valery Gerasimov – until he wrote a certain article in a military periodical. Gerasimov, then recently appointed chief of the general staff of the Russian armed forces, used the piece to reflect on the so-called Arab Spring and the novel role of social media and smartphones in mobilising crowds. He suspected that a new form of warfare was emerging, in which states could achieve more without resorting to armed conflict. If they could incite civil unrest against a rival state, to the 44 | NewScientist | 3 November 2018

point of toppling it, then their own forces might simply roll over the borders – perhaps even in the guise of peacekeepers. Five years on, the “Gerasimov doctrine” is well known as a controversial rethinking of the future of warfare. It also exemplifies the emergence of a new kind of power, one that knows no frontiers and is based

“These firms proudly claim to be ‘disrupters’. Facebook staff are still told to ‘move fast and break things’ ” on the ability to penetrate every device connected to the internet. Two alarming but excellent books, The Death of the Gods by Carl Miller and Nervous States by William Davies, place the doctrine at the centre of the many tools of

The latest tech helped galvanise crowds during the Arab Spring

technochaos. These matter as our familiar institutional landmarks (Miller’s “old gods”) vanish daily, to be replaced by a disturbing and strange combination of internet tech with military might, fake news and populist targeting. Not to mention the rise of cybercrime, tech corporations the size of states, cryptocurrencies and scary algorithms that track and shape individual lives. It is likely that all major powers now have a military capable of digital intervention. Miller reports on his visit to the British army’s 77th Brigade, whose barracks display the motto “behavioural change is our USP”. The brigade already numbers several hundred cyberwarriors.

Later, in eastern Europe, Miller meets the generators of what many in the West would regard as fake news, incentivised by a share of ad revenue from the major Silicon Valley outfits. And he warns of the opaque governance of those companies, proudly claiming to be “disrupters” heralding a new age. Facebook employees are still told to “move fast and break things”, while at Google, workers tell him the company’s central purpose is to “monetise data”. The new forms of power made possible by networked technology, says Miller, “have something in common which older… more recognisable forms of power typically do not. They are far less constrained by rules.” Luckily, there may still be opportunities to resist this. But discovering them means taking into account not just the spread of disinformation, but also why we are vulnerable to it. Davies gives a thoughtful analysis of the influence of fake news and populist rhetoric against experts, statistics and the civil order of liberal democracies. It will not be enough, he argues, to combat them by increasing calls for rational thought and Enlightenment principles. We must also recognise the emotional triggers that make the irrational effective, especially among people who have not fared well in recent decades. Even in the most democratic countries, inequalities in income and wealth have grown, and the burdens of austerity have fallen largely on the poor. Former manufacturing regions no longer offer skilled work, and both physical and mental health are suffering. For those at the sharp end, talk of national economic growth and social progress means little and may be seen as outright lies. Citing a review of psychological studies, Davies finds that what makes people most vulnerable to disinformation are factors linked with self-esteem and control. When people feel their status is

For more books and arts coverage, visit newscientist.com/culture

threatened, and they are victims of social change rather than agents of it, they are more likely to support authoritarian solutions and leaderships that will sweep away the slow process of evidence-based policy-making. Lurking beneath the surface is a resort to violence, which is why Davies finds this “war-in-peace” concept so worrying. A feature of mass mobilisation in war, first used by Napoleon, is to stir up a sense of injury and a desire for

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Call of Duty, Black Ops 4, out now

STANDING in front of a surface coated in Vantablack is terrifying. The nanotech material is the blackest black there is, reflecting so little light back that a room painted floor to ceiling with the stuff makes the world disappear. I feel I’m in a sensory deprivation tank as my eyes and ears strain to get a grip on something, anything. Suddenly, a screen explodes with colour, and the roar of Activision’s latest Call of Duty game, Black Ops 4, shatters the void. “This is VR 2.0,” says Ben Jensen, chief technology officer at UK-based Surrey NanoSystems, the company behind Vantablack. To date, Vantablack’s main industrial use is in precision cameras for satellites or autonomous vehicles, where it prevents interference from stray light. Anish Kapoor, who is the only artist licensed to work with Vantablack, and marketing agencies are also busy dreaming up other uses. This is the first time the largescale version of the paint,VBx2, has been used to paint the inside of a structure. I am with other gamers in a warehouse set up by

Activision to try out Black Ops 4, the biggest, most bombastic of the series. To play well takes skill and reflexes that are easier to develop in an environment that shuts out everything but the game. Could Vantablack offer a no-helmet immersion for virtual worlds? Jensen has played VR games for years, but cuts them short because he finds helmets exhausting. “But in the Vantablack room I feel like I could play all day.” Don’t plan on redecorating your living room though – applying the material isn’t easy, says Jensen. The blackest version of Vantablack reflects just 0.0365 per cent of light. Photons hitting the material get trapped in a carbon nanotube structure, bouncing around until they are absorbed. Jensen’s team has developed sprayable versions of Vantablack, but they still need to be applied in a way that lets the nanostructure build up. “It takes significant training,” he says. “We use robots.” Still, everyone leaving that blacker-than-black room had big grins on their faces. ■

Read Biologist Rob Dunn reminds us we are cultivating a playground for evolution in our ever-cleaner homes in his book Never Home Alone: From microbes to millipedes, camel crickets, and honeybees, the natural history of where we live (Basic Books).

Listen Planetary Radio, the podcast by the Planetary Society, is packed with discussions about the latest astronomical findings. In a recent episode, Cassini project scientist Linda Spilker discusses brand-new data from Saturn.

THE TOM DALE COMPANY

Ben Collyer is a science writer based in Essex, UK

I Infinite (pictured below) is the most powerful 3D immersive entertainment we have seen: a dance performed in a virtual space marked out by image projection. The Tom Dale Company is touring it around the UK until 20 November.

Watch

“For those at the sharp end, talk of national economic growth and social progress means little” revenge: politicians, Davies reminds us, have long understood the “political energy in suffering and defeat”. We are not facing new types of manipulation, but rather a broader and more intrusive method of delivery. Other features of war-in-peace include using emergency powers, merging corporate and state power, telling lies designed to affect morale, increased secrecy and restricting knowledge to small groups. Davies sees signs of these in elite tech companies, in which a handful of billionaires have a tight personal grip on ownership and control, and wield influence without oversight. So how do we resist? Davies thinks experts have a vital role, but only if they recognise and reach out to the emotional component in popular thinking (and their own). More concretely, he suggests we act wherever emotion can usefully help unite populations on rationally sound issues – such as global warming, the #MeToo movement and the Black Lives Matter campaign. These are small seeds of hope perhaps, but they are grounded in an encouraging and novel picture of how we got here, and how we might find a way out. ■

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Douglas Heaven is a consultant for New Scientist 3 November 2018 | NewScientist | 45

CULTURE

It’s a long road to Mars Creating a space epic is an enormously detailed and soul-searching job, discovers Simon Ings The First, created by Beau Willimon, starts on Channel 4 this week. Also available in the US on Hulu

HULU

FOR reasons that remained mysterious by the end of episode one, veteran astronaut Tom Hagerty (Sean Penn) has been grounded. This left him watching helplessly as a launch accident wipes out his former crewmates, bound for Mars on a rocket bankrolled by prickly space visionary Laz Ingram (Natascha McElhone). By the episode’s end, the disaster has taken a huge psychological toll, not least on Ingram herself. Welcome to the future – don’t expect it to be easy. Set 15 years overnight. A Mars project will from now, the world of The First take years of planning.” is not very different from our own. Virtually the whole of the Some cars drive themselves. Media first season of this intriguing gadgets proliferate. The women Martian epic will be set on Earth. who currently hold high executive It is a risky approach, but one positions in private space that persuaded Charles Elachi, companies are now public figures. a former director of NASA’s To hit the next launch Jet Propulsion Laboratory in window, Ingram and thousands California, to be a consultant for of others – in government, in the show. “Only one organisation industry, in NASA and in space “It takes thousands of agencies across the world – are people and thousands of going to have to figure out how they are going to get a second stab years of experience to get one astronaut into space” at Mars. And what’s more, they are going to have to convince their paymasters, their employees, has successfully landed their constituents, their families something on Mars,” he tells me and themselves, that all the time with relish, “and I used to head it.” and sacrifice and renewed risk “What attracted me,” says will be worthwhile. Elachi, “was Willimon’s desire The First is not your typical to look at the Mars project in the fictional voyage to Mars. “It would round, taking in the scientific have been safer to just get into aspects, but also all the technical space in the first episode,” says and personal and political series creator Beau Willimon, best challenges. How do you convince known for his stylish US remake people to commit to these of political thriller House of Cards. amazing projects? Important “But space exploration, with all of as the science is, exploration is its excitement, doesn’t happen a human endeavour.” 46 | NewScientist | 3 November 2018

Elachi has seen the truth of this at first hand, having witnessed the decades of effort and sacrifice required to land rovers on Mars, and he is impressed that the series, although it accelerates events tremendously, still reflects the likely scale of a Mars mission. “The series starts 15 years in the future, but for me, as the show’s technical consultant, it’s really a story of the next 15 years,” says Elachi. “It’s about all the things that come before that first flight: the power sources, the vehicles, all the equipment that needs to be developed and deployed before a human ever boards a rocket.” Building the backstory to the series was essential. And according to Willimon, it was cool: “A lot of the questions we had were questions that researchers themselves are asking,” he says. “Every design element on the screen has a clear function and a precise reason for being there. We don’t want this to be an 8-hour science lecture, but it’s important for the audience that we can explain everything in the frame.”

Sean Penn and LisaGay Hamilton look to the future in The First

It takes thousands of people to get one astronaut into space. Engineers, scientists, the medical team, the ground-support team: people bring thousands of years of combined experience to the business of making several minutes tick by without failure. Willimon, whose father served months at a time on nuclear submarines, also knows the sacrifices families make. While his father was away, he says, “I used to make these drawings and maps and plans, trying to figure out where he was, under what ice shelf, in what ocean? And I’d try to work out what he was doing.” This makes The First a very personal project. “We all ask ourselves, What does it all mean? Is there a God? Where’s my place in the universe?” Willimon reflects. If we asked these things of ourselves all the time, we’d go mad. “But space travel,” he says, “literally travelling into the heavens, forces your hand.” ■

Position Title: Research

Associate Professor

Req # 03919

Department of Chemistry at The University of Chicago invites applications for the position of Research Associate Professor. The successful candidate will be responsible for maintaining a research program and advise graduate students in Theoretical or Computational Chemistry. The candidate is expected to collaborate with experimental and/or theoretical faculty within the department. Ideally, candidates should have demonstrated ability to raise support for their research and lead collaborative projects. *HUKPKH[LZT\Z[OH]LHKVJ[VYH[LPU*OLTPZ[Y`VYYLSH[LKÄLSK HSVUN ^P[O H[ SLHZ[ Ä]L `LHYZ VM WVZ[NYHK\H[L YLZLHYJO HUK teaching experience in Chemistry. The successful candidate will have demonstrated competence in teaching, and have experience mentoring graduate students in Chemistry. Candidates must have evidence of publication and research dissemination. Applicants must apply online at the University of Chicago’s Academic Jobs website https://tinyurl.com/yd8tkptv, and must upload a curriculum vitae and cover letter. Review of applications will begin November 15, 2018 and will JVU[PU\L\U[PS[OLWVZP[PVUPZÄSSLK ;OL