Arquivo mensal: maio 2021

‘Belonging Is Stronger Than Facts’: The Age of Misinformation (The New York Times)

Max Fisher

The Interpreter

Social and psychological forces are combining to make the sharing and believing of misinformation an endemic problem with no easy solution.

An installation of protest art outside the Capitol in Washington.
Credit: Jonathan Ernst/Reuters

Published May 7, 2021; Updated May 13, 2021

There’s a decent chance you’ve had at least one of these rumors, all false, relayed to you as fact recently: that President Biden plans to force Americans to eat less meat; that Virginia is eliminating advanced math in schools to advance racial equality; and that border officials are mass-purchasing copies of Vice President Kamala Harris’s book to hand out to refugee children.

All were amplified by partisan actors. But you’re just as likely, if not more so, to have heard it relayed from someone you know. And you may have noticed that these cycles of falsehood-fueled outrage keep recurring.

We are in an era of endemic misinformation — and outright disinformation. Plenty of bad actors are helping the trend along. But the real drivers, some experts believe, are social and psychological forces that make people prone to sharing and believing misinformation in the first place. And those forces are on the rise.

“Why are misperceptions about contentious issues in politics and science seemingly so persistent and difficult to correct?” Brendan Nyhan, a Dartmouth College political scientist, posed in a new paper in Proceedings of the National Academy of Sciences.

It’s not for want of good information, which is ubiquitous. Exposure to good information does not reliably instill accurate beliefs anyway. Rather, Dr. Nyhan writes, a growing body of evidence suggests that the ultimate culprits are “cognitive and memory limitations, directional motivations to defend or support some group identity or existing belief, and messages from other people and political elites.”

Put more simply, people become more prone to misinformation when three things happen. First, and perhaps most important, is when conditions in society make people feel a greater need for what social scientists call ingrouping — a belief that their social identity is a source of strength and superiority, and that other groups can be blamed for their problems.

As much as we like to think of ourselves as rational beings who put truth-seeking above all else, we are social animals wired for survival. In times of perceived conflict or social change, we seek security in groups. And that makes us eager to consume information, true or not, that lets us see the world as a conflict putting our righteous ingroup against a nefarious outgroup.

This need can emerge especially out of a sense of social destabilization. As a result, misinformation is often prevalent among communities that feel destabilized by unwanted change or, in the case of some minorities, powerless in the face of dominant forces.

Framing everything as a grand conflict against scheming enemies can feel enormously reassuring. And that’s why perhaps the greatest culprit of our era of misinformation may be, more than any one particular misinformer, the era-defining rise in social polarization.

“At the mass level, greater partisan divisions in social identity are generating intense hostility toward opposition partisans,” which has “seemingly increased the political system’s vulnerability to partisan misinformation,” Dr. Nyhan wrote in an earlier paper.

Growing hostility between the two halves of America feeds social distrust, which makes people more prone to rumor and falsehood. It also makes people cling much more tightly to their partisan identities. And once our brains switch into “identity-based conflict” mode, we become desperately hungry for information that will affirm that sense of us versus them, and much less concerned about things like truth or accuracy.

Border officials are not mass-purchasing copies of Vice President Kamala Harris’s book, though the false rumor drew attention.
Credit: Gabriela Bhaskar for The New York Times

In an email, Dr. Nyhan said it could be methodologically difficult to nail down the precise relationship between overall polarization in society and overall misinformation, but there is abundant evidence that an individual with more polarized views becomes more prone to believing falsehoods.

The second driver of the misinformation era is the emergence of high-profile political figures who encourage their followers to indulge their desire for identity-affirming misinformation. After all, an atmosphere of all-out political conflict often benefits those leaders, at least in the short term, by rallying people behind them.

Then there is the third factor — a shift to social media, which is a powerful outlet for composers of disinformation, a pervasive vector for misinformation itself and a multiplier of the other risk factors.

“Media has changed, the environment has changed, and that has a potentially big impact on our natural behavior,” said William J. Brady, a Yale University social psychologist.

“When you post things, you’re highly aware of the feedback that you get, the social feedback in terms of likes and shares,” Dr. Brady said. So when misinformation appeals to social impulses more than the truth does, it gets more attention online, which means people feel rewarded and encouraged for spreading it.

How do we fight disinformation? Join Times tech reporters as they untangle the roots of disinformation and how to combat it. Plus we speak to special guest comedian Sarah Silverman. R.S.V.P. to this subscriber-exclusive event.

“Depending on the platform, especially, humans are very sensitive to social reward,” he said. Research demonstrates that people who get positive feedback for posting inflammatory or false statements become much more likely to do so again in the future. “You are affected by that.”

In 2016, the media scholars Jieun Shin and Kjerstin Thorson analyzed a data set of 300 million tweets from the 2012 election. Twitter users, they found, “selectively share fact-checking messages that cheerlead their own candidate and denigrate the opposing party’s candidate.” And when users encountered a fact-check that revealed their candidate had gotten something wrong, their response wasn’t to get mad at the politician for lying. It was to attack the fact checkers.

“We have found that Twitter users tend to retweet to show approval, argue, gain attention and entertain,” researcher Jon-Patrick Allem wrote last year, summarizing a study he had co-authored. “Truthfulness of a post or accuracy of a claim was not an identified motivation for retweeting.”

In another study, published last month in Nature, a team of psychologists tracked thousands of users interacting with false information. Republican test subjects who were shown a false headline about migrants trying to enter the United States (“Over 500 ‘Migrant Caravaners’ Arrested With Suicide Vests”) mostly identified it as false; only 16 percent called it accurate. But if the experimenters instead asked the subjects to decide whether to share the headline, 51 percent said they would.

“Most people do not want to spread misinformation,” the study’s authors wrote. “But the social media context focuses their attention on factors other than truth and accuracy.”

In a highly polarized society like today’s United States — or, for that matter, India or parts of Europe — those incentives pull heavily toward ingroup solidarity and outgroup derogation. They do not much favor consensus reality or abstract ideals of accuracy.

As people become more prone to misinformation, opportunists and charlatans are also getting better at exploiting this. That can mean tear-it-all-down populists who rise on promises to smash the establishment and control minorities. It can also mean government agencies or freelance hacker groups stirring up social divisions abroad for their benefit. But the roots of the crisis go deeper.

“The problem is that when we encounter opposing views in the age and context of social media, it’s not like reading them in a newspaper while sitting alone,” the sociologist Zeynep Tufekci wrote in a much-circulated MIT Technology Review article. “It’s like hearing them from the opposing team while sitting with our fellow fans in a football stadium. Online, we’re connected with our communities, and we seek approval from our like-minded peers. We bond with our team by yelling at the fans of the other one.”

In an ecosystem where that sense of identity conflict is all-consuming, she wrote, “belonging is stronger than facts.”

Study finds humans are directly influencing wind and weather over North Atlantic (EurekaAlert!)

News Release 17-Apr-2021

The findings suggest that winters in Europe and in eastern US may get warmer and wetter

University of Miami Rosenstiel School of Marine & Atmospheric Science

Research News

IMAGE: The Positive NAO index phase shows a stronger than usual subtropical high pressure center and a deeper than normal Icelandic low. The increased pressure difference results in more and stronger… view more  Credit: Columbia University Lamont-Doherty Earth Observatory.

MIAMI–A new study led by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science provides evidence that humans are influencing wind and weather patterns across the eastern United States and western Europe by releasing CO2 and other pollutants into Earth’s atmosphere.

In the new paper, published in the journal npj Climate and Atmospheric Science, the research team found that changes in the last 50 years to an important weather phenomenon in the North Atlantic–known as the North Atlantic Oscillation–can be traced back to human activities that impact the climate system.

“Scientists have long understood that human actions are warming the planet,” said the study’s lead author Jeremy Klavans, a UM Rosenstiel School alumnus. “However, this human-induced signal on weather patterns is much harder to identify.”

“In this study, we show that humans are influencing patterns of weather and climate over the Atlantic and that we may be able to use this information predict changes in weather and climate up to a decade in advance,” said Klavans.

The North Atlantic Oscillation, the result of fluctuations in air pressure across the Atlantic, affects weather by influencing the intensity and location of the jet stream. This oscillation has a strong effect on winter weather in Europe, Greenland, the northeastern U.S. and North Africa and the quality of crop yields and productivity of fisheries in the North Atlantic.

The researchers used multiple large climate model ensembles, compiled by researchers at the National Center for Atmospheric Research, to predict the North Atlantic Oscillation. The analysis consisted of 269 model runs, which is over 14,000 simulated model years.

The study, titled “NAO Predictability from External Forcing in the Late Twentieth Century,” was published on March 25 in the journal npj Climate and Atmospheric Science. The study’s authors include: Klavans, Amy Clement and Lisa Murphy from the UM Rosenstiel School, and Mark Cane from Columbia University’s Lamont-Doherty Earth Observatory.

The study was supported by the National Science Foundation (NSF) Climate and Large-Scale Dynamics program (grant # AGS 1735245 and AGS 1650209), NSF Paleo Perspectives on Climate Change program (grant # AGS 1703076) and NOAA’s Climate Variability and Predictability Program.

Human Brain Limit of ‘150 Friends’ Doesn’t Check Out, New Study Claims (Science Alert)

Peter Dockrill – 5 MAY 2021

It’s called Dunbar’s number: an influential and oft-repeated theory suggesting the average person can only maintain about 150 stable social relationships with other people.

Proposed by British anthropologist and evolutionary psychologist Robin Dunbar in the early 1990s, Dunbar’s number, extrapolated from research into primate brain sizes and their social groups, has since become a ubiquitous part of the discourse on human social networks.

But just how legitimate is the science behind Dunbar’s number anyway? According to a new analysis by researchers from Stockholm University in Sweden, Dunbar’s famous figure doesn’t add up.

“The theoretical foundation of Dunbar’s number is shaky,” says zoologist and cultural evolution researcher Patrik Lindenfors.

“Other primates’ brains do not handle information exactly as human brains do, and primate sociality is primarily explained by other factors than the brain, such as what they eat and who their predators are.”

Dunbar’s number was originally predicated on the idea that the volume of the neocortex in primate brains functions as a constraint on the size of the social groups they circulate amongst.

“It is suggested that the number of neocortical neurons limits the organism’s information-processing capacity and that this then limits the number of relationships that an individual can monitor simultaneously,” Dunbar explained in his foundational 1992 study.

“When a group’s size exceeds this limit, it becomes unstable and begins to fragment. This then places an upper limit on the size of groups which any given species can maintain as cohesive social units through time.”

Dunbar began extrapolating the theory to human networks in 1993, and in the decades since has authored and co-authored copious related research output examining the behavioral and cognitive mechanisms underpinning sociality in both humans and other primates.

But as to the original question of whether neocortex size serves as a valid constraint on group size beyond non-human primates, Lindenfors and his team aren’t so sure.

While a number of studies have offered support for Dunbar’s ideas, the new study debunks the claim that neocortex size in primates is equally pertinent to human socialization parameters.

“It is not possible to make an estimate for humans with any precision using available methods and data,” says evolutionary biologist Andreas Wartel.

In their study, the researchers used modern statistical methods including Bayesian and generalized least-squares (GLS) analyses to take another look at the relationship between group size and brain/neocortex sizes in primate brains, with the advantage of updated datasets on primate brains.

The results suggested that stable human group sizes might ultimately be much smaller than 150 individuals – with one analysis suggesting up to 42 individuals could be the average limit, with another estimate ranging between a group of 70 to 107.

Ultimately, however, enormous amounts of imprecision in the statistics suggest that any method like this – trying to compute an average number of stable relationships for any human individual based off brain volume considerations – is unreliable at best.

“Specifying any one number is futile,” the researchers write in their study. “A cognitive limit on human group size cannot be derived in this manner.”

Despite the mainstream attention Dunbar’s number enjoys, the researchers say the majority of primate social evolution research focuses on socio-ecological factors, including foraging and predation, infanticide, and sexual selection – not so much calculations dependent on brain or neocortex volume.

Further, the researchers argue that Dunbar’s number ignores other significant differences in brain physiology between human and non-human primate brains – including that humans develop cultural mechanisms and social structures that can counter socially limiting cognitive factors that might otherwise apply to non-human primates.

“Ecological research on primate sociality, the uniqueness of human thinking, and empirical observations all indicate that there is no hard cognitive limit on human sociality,” the team explains.

“It is our hope, though perhaps futile, that this study will put an end to the use of ‘Dunbar’s number’ within science and in popular media.”

The findings are reported in Biology Letters.

Your Immune System Could Be Hurting You as a Way of Signalling to Others (Science Alert)

Jonathan R Goodman, The Conversation – 13 May 2021

A major debate during the pandemic, and in infectious disease research more broadly, is why infected people die. No virus “wants” to kill anyone, as an epidemiologist once said to me. Like any other form of life, a virus’s goal is only to survive and reproduce.

A growing body of evidence instead suggests that the human immune system – which the science writer Ed Yong says is “where intuition goes to die” – may itself be responsible for many people’s deaths.

In an effort to find and kill the invading virus, the body can harm major organs, including the lungs and heart. This has led some doctors to focus on attenuating an infected patient’s immune response to help save them.

This brings up an evolutionary puzzle: what’s the point of the immune system if its overzealousness can kill the same people it evolved to defend?

The answer may lie in humanity’s evolutionary history: immunity may be as much about communication and behavior as it is about cellular biology. And to the degree that researchers can understand these broad origins of the immune system, they may be better positioned to improve responses to it.

The concept of the behavioral immune system is not new. Almost all humans sometimes feel disgust or revulsion – usually because whatever has made us feel that way poses a threat to our health.

And we aren’t alone in these reactions. Research shows that some animals avoid others that are showing symptoms of illness.

Eliciting care

However, more recent theoretical research suggests something more: humans, in particular, are likely to show compassion to those showing symptoms of illness or injury.

There’s a reason, this thinking goes, why people tend to exclaim when in pain, rather than just silently pull away from whatever is hurting them, and why fevers are linked to sluggish behavior.

Some psychologists argue that this is because immune responses are as much about communication as they are about self-maintenance. People who received care, over humanity’s history, probably tended to do better than those who tried to survive on their own.

In the broader evolutionary literature, researchers refer to these kinds of displays as “signals”. And like many of the innumerable signals we see across the natural world, immune-related signals can be used – or faked – to exploit the world around us, and each other.

Some birds, for example, feign injury to distract predators from their nests; rats suppress disease symptoms so that potential mates won’t ignore them.

We also see many illustrations of immune-signal use and misuse in human cultures. In The Adventure of the Dying Detective (1913), for example, Sherlock Holmes starves himself for three days to elicit a confession from a murder suspect. The suspect confesses only when he is convinced that his attempt to infect Holmes with a rare disease has been successful, misreading Holmes’s signs of illness.

This is an extreme example, but people feign signals of pain or illness all the time to avoid obligations, to elicit support from others, or even to avoid submitting an article by an agreed deadline. And this is an essential element of any signalling system.

Once a signal, be it a wince or a jaundiced complexion, elicits a response from whoever sees it, that response will start to drive how and why the signal is used.

Even germs use – and abuse – immune signals for their own gain. In fact, some viruses actually hijack our own immune responses, such as coughs and sneezes, to pass themselves on to new hosts, using our own evolved functions to further their interests.

Other germs, like SARS-CoV-2 (the virus that causes COVID-19) and Yersinia pestis (the bacterium that causes plague), can prevent our signalling to others when we are sick and pass themselves on without anyone realizing.

This perspective of immunity – one that takes into account biology, behavior and the social effects of illness – paints a starkly different picture from the more traditional view of the immune system as a collection of biological and chemical defenses against sickness.

Germs use different strategies, just as animals do, to exploit immune signals for their own purposes. And perhaps that’s what has made asymptomatically transmitted COVID-19 so damaging: people can’t rely on reading other people’s immune signals to protect themselves.

Insofar as doctors can predict how a particular infection – whether SARS-CoV-2, influenza, malaria or the next pathogen with pandemic potential – will interact with a patient’s immune system, they’ll be better positioned to tailor treatments for it. Future research will help us sort through the germs that hijack our immune signals – or suppress them – for their own purposes.

Viewing immunity not just as biological, but as a broader signalling system, may help us to understand our complex relationships with pathogens more effectively.

Jonathan R Goodman, PhD Candidate, Human Evolutionary Studies, University of Cambridge.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Ten million reasons to vaccinate the world (The Economist)

Our model reveals the true course of the pandemic. Here is what to do next

May 15th 2021 8-10 minutos

THIS WEEK we publish our estimate of the true death toll from covid-19. It tells the real story of the pandemic. But it also contains an urgent warning. Unless vaccine supplies reach poorer countries, the tragic scenes now unfolding in India risk being repeated elsewhere. Millions more will die.

Using known data on 121 variables, from recorded deaths to demography, we have built a pattern of correlations that lets us fill in gaps where numbers are lacking. Our model suggests that covid-19 has already claimed 7.1m-12.7m lives. Our central estimate is that 10m people have died who would otherwise be living. This tally of “excess deaths” is over three times the official count, which nevertheless is the basis for most statistics on the disease, including fatality rates and cross-country comparisons.

The most important insight from our work is that covid-19 has been harder on the poor than anyone knew. Official figures suggest that the pandemic has struck in waves, and that the United States and Europe have been hit hard. Although South America has been ravaged, the rest of the developing world seemed to get off lightly.

Our modelling tells another story. When you count all the bodies, you see that the pandemic has spread remorselessly from the rich, connected world to poorer, more isolated places. As it has done so, the global daily death rate has climbed steeply.

Death rates have been very high in some rich countries, but the overwhelming majority of the 6.7m or so deaths that nobody counted were in poor and middle-income ones. In Romania and Iran excess deaths are more than double the number officially put down to covid-19. In Egypt they are 13 times as big. In America the difference is 7.1%.

India, where about 20,000 are dying every day, is not an outlier. Our figures suggest that, in terms of deaths as a share of population, Peru’s pandemic has been 2.5 times worse than India’s. The disease is working its way through Nepal and Pakistan. Infectious variants spread faster and, because of the tyranny of exponential growth, overwhelm health-care systems and fill mortuaries even if the virus is no more lethal.

Ultimately the way to stop this is vaccination. As an example of collaboration and pioneering science, covid-19 vaccines rank with the Apollo space programme. Within just a year of the virus being discovered, people could be protected from severe disease and death. Hundreds of millions of them have benefited.

However, in the short run vaccines will fuel the divide between rich and poor. Soon, the only people to die from covid-19 in rich countries will be exceptionally frail or exceptionally unlucky, as well as those who have spurned the chance to be vaccinated. In poorer countries, by contrast, most people will have no choice. They will remain unprotected for many months or years.

The world cannot rest while people perish for want of a jab costing as little as $4 for a two-dose course. It is hard to think of a better use of resources than vaccination. Economists’ central estimate for the direct value of a course is $2,900—if you include factors like long covid and the effect of impaired education, the total is much bigger. The benefit from an extra 1bn doses supplied by July would be worth hundreds of billions of dollars. Less circulating virus means less mutation, and so a lower chance of a new variant that reinfects the vaccinated.

Supplies of vaccines are already growing. By the end of April, according to Airfinity, an analytics firm, vaccine-makers produced 1.7bn doses, 700m more than the end of March and ten times more than January. Before the pandemic, annual global vaccine capacity was roughly 3.5bn doses. The latest estimates are that total output in 2021 will be almost 11bn. Some in the industry predict a global surplus in 2022.

And yet the world is right to strive to get more doses in more arms sooner. Hence President Joe Biden has proposed waiving intellectual-property claims on covid-19 vaccines. Many experts argue that, because some manufacturing capacity is going begging, millions more doses might become available if patent-owners shared their secrets, including in countries that today are at the back of the queue. World-trade rules allow for a waiver. When invoke them if not in the throes of a pandemic?

We believe that Mr Biden is wrong. A waiver may signal that his administration cares about the world, but it is at best an empty gesture and at worst a cynical one.

A waiver will do nothing to fill the urgent shortfall of doses in 2021. The head of the World Trade Organisation, the forum where it will be thrashed out, warns there may be no vote until December. Technology transfer would take six months or so to complete even if it started today. With the new mRNA vaccines made by Pfizer and Moderna, it may take longer. Supposing the tech transfer was faster than that, experienced vaccine-makers would be unavailable for hire and makers could not obtain inputs from suppliers whose order books are already bursting. Pfizer’s vaccine requires 280 inputs from suppliers in 19 countries. No firm can recreate that in a hurry.

In any case, vaccine-makers do not appear to be hoarding their technology—otherwise output would not be increasing so fast. They have struck 214 technology-transfer agreements, an unprecedented number. They are not price-gouging: money is not the constraint on vaccination. Poor countries are not being priced out of the market: their vaccines are coming through COVAX, a global distribution scheme funded by donors.

In the longer term, the effect of a waiver is unpredictable. Perhaps it will indeed lead to technology being transferred to poor countries; more likely, though, it will cause harm by disrupting supply chains, wasting resources and, ultimately, deterring innovation. Whatever the case, if vaccines are nearing a surplus in 2022, the cavalry will arrive too late.

A needle in time

If Mr Biden really wants to make a difference, he can donate vaccine right now through COVAX. Rich countries over-ordered because they did not know which vaccines would work. Britain has ordered more than nine doses for each adult, Canada more than 13. These will be urgently needed elsewhere. It is wrong to put teenagers, who have a minuscule risk of dying from covid-19, before the elderly and health-care workers in poor countries. The rich world should not stockpile boosters to cover the population many times over on the off-chance that they may be needed. In the next six months, this could yield billions of doses of vaccine.

Countries can also improve supply chains. The Serum Institute, an Indian vaccine-maker, has struggled to get parts such as filters from America because exports were gummed up by the Defence Production Act (DPA), which puts suppliers on a war-footing. Mr Biden authorised a one-off release, but he should be focusing the DPA on supplying the world instead. And better use needs to be made of finished vaccine. In some poor countries, vaccine languishes unused because of hesitancy and chaotic organisation. It makes sense to prioritise getting one shot into every vulnerable arm, before setting about the second.

Our model is not predictive. However it does suggest that some parts of the world are particularly vulnerable—one example is South-East Asia, home to over 650m people, which has so far been spared mass fatalities for no obvious reason. Covid-19 has not yet run its course. But vaccines have created the chance to save millions of lives. The world must not squander it. ■

Dig deeper

All our stories relating to the pandemic and the vaccines can be found on our coronavirus hub. You can also listen to The Jab, our podcast on the race between injections and infections, and find trackers showing the global roll-out of vaccines, excess deaths by country and the virus’s spread across Europe and America.

This article appeared in the Leaders section of the print edition under the headline “Vaccinating the world”

Neanderthals carb loaded, helping grow their big brains (Science)

By Ann GibbonsMay. 10, 2021 , 3:00 PM 5-7 minutos

A reconstruction of Neanderthal mealtime Mauricio Anton/Science Source

Here’s another blow to the popular image of Neanderthals as brutish meat eaters: A new study of bacteria collected from Neanderthal teeth shows that our close cousins ate so many roots, nuts, or other starchy foods that they dramatically altered the type of bacteria in their mouths. The finding suggests our ancestors had adapted to eating lots of starch by at least 600,000 years ago—about the same time as they needed more sugars to fuel a big expansion of their brains.

The study is “groundbreaking,” says Harvard University evolutionary biologist Rachel Carmody, who was not part of the research. The work suggests the ancestors of both humans and Neanderthals were cooking lots of starchy foods at least 600,000 years ago. And they had already adapted to eating more starchy plants long before the invention of agriculture 10,000 years ago, she says.

The brains of our ancestors doubled in size between 2 million and 700,000 years ago. Researchers have long credited better stone tools and cooperative hunting: As early humans got better at killing animals and processing meat, they ate a higher quality diet, which gave them more energy more rapidly to fuel the growth of their hungrier brains.

Still, researchers have puzzled over how meat did the job. “For human ancestors to efficiently grow a bigger brain, they needed energy dense foods containing glucose”—a type of sugar—says molecular archaeologist Christina Warinner of Harvard and the Max Planck Institute for the Science of Human History. “Meat is not a good source of glucose.”

Researchers analyzed the bacterial DNA preserved in dental plaque of fossilized teeth, such as this one from a prehistoric human. Werner Siemens Foundation/Felix Wey

The starchy plants gathered by many living hunter-gatherers are an excellent source of glucose, however. To figure out whether oral bacteria track changes in diet or the environment, Warinner, Max Planck graduate student James Fellows Yates, and a large international team looked at the oral bacteria stuck to the teeth of Neanderthals, preagriculture modern humans that lived more than 10,000 years ago, chimps, gorillas, and howler monkeys. The researchers analyzed billions of DNA fragments from long-dead bacteria still preserved on the teeth of 124 individuals. One was a Neanderthal who lived 100,000 years ago at Pešturina Cave in Serbia, which produced the oldest oral microbiome genome reconstructed to date.

The communities of bacteria in the mouths of preagricultural humans and Neanderthals strongly resembled each other, the team reports today in the Proceedings of the National Academy of Sciences. In particular, humans and Neanderthals harbored an unusual group of Streptococcus bacteria in their mouths. These microbes had a special ability to bind to an abundant enzyme in human saliva called amylase, which frees sugars from starchy foods. The presence of the strep bacteria that consume sugar on the teeth of Neanderthals and ancient modern humans, but not chimps, shows they were eating more starchy foods, the researchers conclude.

Finding the streptococci on the teeth of both ancient humans and Neanderthals also suggests they inherited these microbes from their common ancestor, who lived more than 600,000 years ago. Although earlier studies found evidence that Neanderthals ate grasses and tubers and cooked barley, the new study indicates they ate so much starch that it dramatically altered the composition of their oral microbiomes.

“This pushes the importance of starch in the diet further back in time,” to when human brains were still expanding, Warinner says. Because the amylase enzyme is much more efficient at digesting cooked rather than raw starch, the finding also suggests cooking, too, was common by 600,000 years ago, Carmody says. Researchers have debated whether cooking became common when the big brain began to expand almost 2 million years ago or it spread later, during a second surge of growth.

The study offers a new way to detect major shifts in diet, says geneticist Ran Blekhman of the University of Minnesota, Twin Cities. In the case of Neanderthals, it reveals how much they depended on plants.

“We sometimes have given short shrift to the plant components of the diet,” says anthropological geneticist Anne Stone of Arizona State University, Tempe. “As we know from modern hunter-gatherers, it’s often the gathering that ends up providing a substantial portion of the calories.”

Foto de criança expõe crise na assistência à saúde dos yanomamis (Folha de S.Paulo)

Território sofre com o aumento da malária e com a desnutrição infantil crônica

9.mai.2021 às 12h00 Atualizado: 9.mai.2021 às 20h02

Fabiano Maisonnave

Manaus Na aldeia Maimasi, em Roraima, uma criança yanomami jaz sobre a rede. Com as costelas expostas pela desnutrição, ela foi diagnosticada com malária e verminose. Mas a primeira equipe médica no local em seis meses não dispunha de medicamentos suficientes para tratar toda a aldeia.

A foto dessa criança e a história por trás dela foram obtidas pelo missionário católico Carlo Zacquini, 84, que atua entre os yanomamis desde 1968. Ele é cofundador da Comissão pela Criação do Parque Yanomami (CCPY), que deu visibilidade aos problemas causados pelos brancos, promoveu atendimento em saúde e lutou pela demarcação, concluída em 1992.

O território yanomami sofre com o aumento da malária e com a desnutrição infantil crônica, que atinge 80% das crianças até 5 anos, segundo estudo recente financiado pela Unicef e realizado em parceria com a Fiocruz e o Ministério da Saúde.

Os indígenas também enfrentam uma grande invasão de garimpeiros, incentivados por promessas do presidente Jair Bolsonaro de legalizá-los e pelo alto preço do minério. São cerca de 20 mil não indígenas morando ilegalmente na Terra Indígena Yanomami, contaminando os rios com mercúrio e contribuindo para espalhar Covid-19 e malária, além do álcool e da prostituição.

Procurado, o Distrito Sanitário Especial Indígena (Dsei) Yanomami, do Ministério da Saúde, informou que a criança, do sexo feminino, foi transferida a Boa Vista (RR) dois dias após a visita médica, acompanhada dos pais e dos irmãos.

Ela tem 8 anos e pesa 12,5 kg. Internada desde 23 de abril, está em tratamento para pneumonia, anemia e desnutrição grave —a malária foi curada. Ela está estável e em acompanhamento pelo serviço social. Segundo o órgão, trata-se de um caso isolado.

O Dsei negou a escassez de medicamentos e afirma que a quantidade é definida de acordo com a demanda prevista pela semana epidemiológica. O órgão não informou sobre como está o tratamento de outros yanomamis doentes na mesma região, mas alega que o atendimento de saúde é dificultado pelo fluxo constante dos indígenas e atribuiu a alta de incidência de malária à presença do garimpo ilegal.

A seguir, o depoimento de Zacquini:

É uma criança da aldeia Maimasi, a dois dias a pé da Missão Catrimani. Ela está sem assistência há muito tempo, com malária e verminose.

A fotografia foi feita por volta de 17 de abril. O pessoal das equipes de saúde tem receio de denunciar essa situação, pois podem ser punidos, colocados em lugares mais penosos ou ser demitidos. Vários polos de saúde estão abandonados. Não há estoque de medicamentos para verminose na sede do Dsei (Distrito Sanitário Especial Indígena Yanomami), em Boa Vista. Até para malária a quantidade é limitada.

O posto de saúde tem muita dificuldade para conseguir medicamentos. Faltam profissionais para revezamento e falta gasolina para deslocamento. Há três meses, eles usam a canoa com rabeta [motor] dos próprios yanomamis.

Criança magra ao ponto de ter ossos visíveis sob a pele, em rede
Com quadro de verminose e malária, criança yanomami dorme em rede na aldeia Maimasi, perto da Missão Catrimani, na Terra Indígena Yanomami, em Roraima – Divulgação

Para chegar a Maimasi, seriam oito minutos de helicóptero, mas, a princípio, isso só ocorre em casos de emergência. Evidentemente, essa criança é um caso de emergência!

Para levar medicamento ao pólo-base, foram deslocados um avião com uma equipe médica, porém eles ficaram aguardando inutilmente a chegada do helicóptero.

Havia seis meses que ninguém visitava a aldeia. Dessa vez, foram medicamentos para malária, mas não deu para repetir a dose. Uma equipe da Sesai (Secretaria Especial de Saúde Indígena, do Ministério da Saúde), incluindo médico, foi de avião até a Missão Catrimani para levar esses medicamentos.

O pessoal da saúde faz tratamentos com medicamentos, mas o tratamento não tem continuidade quando trocam de equipe. Assim, quando possível, fazem a primeira dose de tratamento, mas depois de um tempo os doentes devem recomeçar a partir da primeira dose.

Estou revoltado e com o sangue fervendo. É uma situação que parece estar se generalizando na Terra Indígena Yanomami.

O vaivém de garimpeiros é contínuo e isso implica voos de avião, barcos, helicópteros e a pé. São milhares os invasores da Terra Indígena Yanomami, e o presidente da República anuncia que irá pessoalmente falar com os militares que estão ali e com os garimpeiros também. Faz questão de dizer que não vai prender estes últimos, mas somente conversar.

Até para malária os medicamentos são contados, incluindo a cloroquina. Tem cloroquina para Covid, mas não para malária. A criança desnutrida está numa aldeia a oito minutos de helicóptero de um posto de saúde, mas leva um dia a pé. E depois dessa aldeia há outras, que na época estavam reunidas para o cerimonial funerário em outra aldeia mais afastada.

A equipe do pólo-base se deslocou a pé para a aldeia e encontrou um grupo grande de yanomamis que fazia um ritual funerário para uma criança que tinha morrido sem assistência. Eles ministraram medicamentos para verminose a todos, mas esse medicamento acabou e não puderam dar uma outra dose, o que é a praxe.

Aliás, havia mais de um ano que aquelas aldeias não recebiam atendimento contra verminose. A criança da foto e outros 16 indígenas presentes estavam com malária, a maioria deles com falciparum, a variedade mais agressiva. Os demais 84 estavam todos com sintomas de gripe e de febre.

A Diversity of Wildlife Is Good for Our Health: To Prevent Future Pandemics, We Must Restore and Protect Nature (SciTechDaily)

By Cary Institute of Ecosystem Studies on May 08, 2021

Ecosystems with a diversity of mammals, including larger-bodies and longer lived creatures like foxes, are better for our health. Credit: Ali Rajabali / Flickr

A growing body of evidence suggests that biodiversity loss increases our exposure to both new and established zoonotic pathogens. Restoring and protecting nature is essential to preventing future pandemics. So reports a new Proceedings of the National Academy of Sciences (PNAS) paper that synthesizes current understanding about how biodiversity affects human health and provides recommendations for future research to guide management.

Lead author Felicia Keesing is a professor at Bard College and a Visiting Scientist at Cary Institute of Ecosystem Studies. She explains, “There’s a persistent myth that wild areas with high levels of biodiversity are hotspots for disease. More animal diversity must equal more dangerous pathogens. But this turns out to be wrong. Biodiversity isn’t a threat to us, it’s actually protecting us from the species most likely to make us sick.”

Zoonotic diseases like COVID-19, SARS, and Ebola are caused by pathogens that are shared between humans and other vertebrate animals. But animal species differ in their ability to pass along pathogens that make us sick.

Rick Ostfeld is a disease ecologist at Cary Institute and a co-author on the paper. He explains, “Research is mounting that species that thrive in developed and degraded landscapes are often much more efficient at harboring pathogens and transmitting them to people. In less-disturbed landscapes with more animal diversity, these risky reservoirs are less abundant and biodiversity has a protective effect.”

Rodents, bats, primates, cloven-hooved mammals like sheep and deer, and carnivores have been flagged as the mammal taxa most likely to transmit pathogens to humans. Keesing and Ostfeld note, “The next emerging pathogen is far more likely to come from a rat than a rhino.”

This is because animals with fast life histories tend to be more efficient at transmitting pathogens. Keesing explains, “Animals that live fast, die young, and have early sexual maturity with lots of offspring tend to invest less in their adaptive immune responses. They are often better at transmitting diseases, compared to longer-lived animals with stronger adaptive immunity.”

When biodiversity is lost from ecological communities, long-lived, larger-bodied species tend to disappear first, while smaller-bodied species with fast life histories tend to proliferate. Research has found that mammal hosts of zoonotic viruses are less likely to be species of conservation concern (i.e. they are more common), and that for both mammals and birds, human development tends to increase the abundance of zoonotic host species, bringing people and risky animals closer together.

“When we erode biodiversity, we favor species that are more likely to be zoonotic hosts, increasing our risk of spillover events,” Ostfeld notes. Adding that, “Managing this risk will require a better understanding of how things like habitat conversion, climate change, and overharvesting affect zoonotic hosts, and how restoring biodiversity to degraded areas might reduce their abundance.”

To predict and prevent spillover, Keesing and Ostfeld highlight the need to focus on host attributes associated with disease transmission rather than continuing to debate the prime importance of one taxon or another. Ostfeld explains, “We should stop assuming that there is a single animal source for each emerging pathogen. The pathogens that jump from animals to people tend to be found in many animal species, not just one. They’re jumpers, after all, and they typically move between species readily.”

Disentangling the characteristics of effective zoonotic hosts – such as their immune strategies, resilience to disturbance, and habitat preferences – is key to protecting public health. Forecasting the locations where these species thrive, and where pathogen transmission and emergence are likely, can guide targeted interventions.

Keesing notes, “Restoration of biodiversity is an important frontier in the management of zoonotic disease risk. Those pathogens that do spill over to infect humans–zoonotic pathogens–often proliferate as a result of human impacts.” Concluding, “As we rebuild our communities after COVID-19, we need to have firmly in mind that one of our best strategies to prevent future pandemics is to protect, preserve, and restore biodiversity.”

Reference: “Impacts of biodiversity and biodiversity loss on zoonotic diseases” by Felicia Keesing and Richard S. Ostfeld, 5 April 2021, Proceedings of National Academy of Sciences.
DOI: 10.1073/pnas.2023540118

This research was supported by a National Science Foundation Grant OPUS 1948419 to Keesing.

Cary Institute of Ecosystem Studies is an independent nonprofit center for environmental research. Since 1983, our scientists have been investigating the complex interactions that govern the natural world and the impacts of climate change on these systems. Our findings lead to more effective management and policy actions and increased environmental literacy. Staff are global experts in the ecology of: cities, disease, forests, and freshwater.

Inventing the Universe (The New Atlantis)

Winter 2020

David Kordahl

Two new books on quantum theory could not, at first glance, seem more different. The first, Something Deeply Hidden, is by Sean Carroll, a physicist at the California Institute of Technology, who writes, “As far as we currently know, quantum mechanics isn’t just an approximation of the truth; it is the truth.” The second, Einstein’s Unfinished Revolution, is by Lee Smolin of the Perimeter Institute for Theoretical Physics in Ontario, who insists that “the conceptual problems and raging disagreements that have bedeviled quantum mechanics since its inception are unsolved and unsolvable, for the simple reason that the theory is wrong.”

Given this contrast, one might expect Carroll and Smolin to emphasize very different things in their books. Yet the books mirror each other, down to chapters that present the same quantum demonstrations and the same quantum parables. Carroll and Smolin both agree on the facts of quantum theory, and both gesture toward the same historical signposts. Both consider themselves realists, in the tradition of Albert Einstein. They want to finish his work of unifying physical theory, making it offer one coherent description of the entire world, without ad hoc exceptions to cover experimental findings that don’t fit. By the end, both suggest that the completion of this project might force us to abandon the idea of three-dimensional space as a fundamental structure of the universe.

But with Carroll claiming quantum mechanics as literally true and Smolin claiming it as literally false, there must be some underlying disagreement. And of course there is. Traditional quantum theory describes things like electrons as smeary waves whose measurable properties only become definite in the act of measurement. Sean Carroll is a supporter of the “Many Worlds” interpretation of this theory, which claims that the multiple measurement possibilities all simultaneously exist. Some proponents of Many Worlds describe the existence of a “multiverse” that contains many parallel universes, but Carroll prefers to describe a single, radically enlarged universe that contains all the possible outcomes running alongside each other as separate “worlds.” But the trouble, says Lee Smolin, is that in the real world as we observe it, these multiple possibilities never appear — each measurement has a single outcome. Smolin takes this fact as evidence that quantum theory must be wrong, and argues that any theory that supersedes quantum mechanics must do away with these multiple possibilities.

So how can such similar books, informed by the same evidence and drawing upon the same history, reach such divergent conclusions? Well, anyone who cares about politics knows that this type of informed disagreement happens all the time, especially, as with Carroll and Smolin, when the disagreements go well beyond questions that experiments could possibly resolve.

But there is another problem here. The question that both physicists gloss over is that of just how much we should expect to get out of our best physical theories. This question pokes through the foundation of quantum mechanics like rusted rebar, often luring scientists into arguments over parables meant to illuminate the obscure.

With this in mind, let’s try a parable of our own, a cartoon of the quantum predicament. In the tradition of such parables, it’s a story about knowing and not knowing.

We fade in on a scientist interviewing for a job. Let’s give this scientist a name, Bobby Alice, that telegraphs his helplessness to our didactic whims. During the part of the interview where the Reality Industries rep asks him if he has any questions, none of them are answered, except the one about his starting salary. This number is high enough to convince Bobby the job is right for him.

Knowing so little about Reality Industries, everything Bobby sees on his first day comes as a surprise, starting with the campus’s extensive security apparatus of long gated driveways, high tree-lined fences, and all the other standard X-Files elements. Most striking of all is his assigned building, a structure whose paradoxical design merits a special section of the morning orientation. After Bobby is given his project details (irrelevant for us), black-suited Mr. Smith–types tell him the bad news: So long as he works at Reality Industries, he may visit only the building’s fourth floor. This, they assure him, is standard, for all employees but the top executives. Each project team has its own floor, and the teams are never allowed to intermix.

The instructors follow this with what they claim is the good news. Yes, they admit, this tightly tiered approach led to worker distress in the old days, back on the old campus, where the building designs were brutalist and the depression rates were high. But the new building is designed to subvert such pressures. The trainers lead Bobby up to the fourth floor, up to his assignment, through a construction unlike any research facility he has ever seen. The walls are translucent and glow on all sides. So do the floor and ceiling. He is guided to look up, where he can see dark footprints roving about, shadows from the project team on the next floor. “The goal here,” his guide remarks, “is to encourage a sort of cultural continuity, even if we can’t all communicate.”

Over the next weeks, Bobby Alice becomes accustomed to the silent figures floating above him. Eventually, he comes to enjoy the fourth floor’s communal tracking of their fifth-floor counterparts, complete with invented names, invented personalities, invented purposes. He makes peace with the possibility that he is himself a fantasy figure for the third floor.

Then, one day, strange lights appear in a corner of the ceiling.

Naturally phlegmatic, Bobby Alice simply takes notes. But others on the fourth floor are noticeably less calm. The lights seem not to follow any known standard of the physics of footfalls, with lights of different colors blinking on and off seemingly at random, yet still giving the impression not merely of a constructed display but of some solid fixture in the fifth-floor commons. Some team members, formerly of the same anti-philosophical bent as most hires, now spend their coffee breaks discussing increasingly esoteric metaphysics. Productivity declines.

Meanwhile, Bobby has set up a camera to record data. As a work-related extracurricular, he is able in the following weeks to develop a general mathematical description that captures an unexpected order in the flashing lights. This description does not predict exactly which lights will blink when, but, by telling a story about what’s going on between the frames captured by the camera, he can predict what sorts of patterns are allowed, how often, and in what order.

Does this solve the mystery? Apparently it does. Conspiratorial voices on the fourth floor go quiet. The “Alice formalism” immediately finds other applications, and Reality Industries gives Dr. Alice a raise. They give him everything he could want — everything except access to the fifth floor.

In time, Bobby Alice becomes a fourth-floor legend. Yet as the years pass — and pass with the corner lights as an apparently permanent fixture — new employees occasionally massage the Alice formalism to unexpected ends. One worker discovers that he can rid the lights of their randomness if he imagines them as the reflections from a tank of iridescent fish, with the illusion of randomness arising in part because it’s a 3-D projection on a 2-D ceiling, and in part because the fish swim funny. The Alice formalism offers a series of color maps showing the different possible light patterns that might appear at any given moment, and another prominent interpreter argues, with supposed sincerity (although it’s hard to tell), that actually not one but all of the maps occur at once — each in parallel branching universes generated by that spooky alien light source up on the fifth floor.

As the interpretations proliferate, Reality Industries management occasionally finds these side quests to be a drain on corporate resources. But during the Alice decades, the fourth floor has somehow become the company’s most productive. Why? Who knows. Why fight it?

The history of quantum mechanics, being a matter of record, obviously has more twists than any illustrative cartoon can capture. Readers interested in that history are encouraged to read Adam Becker’s recent retelling, What Is Real?, which was reviewed in these pages (“Make Physics Real Again,” Winter 2019). But the above sketch is one attempt to capture the unusual flavor of this history.

Like the fourth-floor scientists in our story who, sight unseen, invented personas for all their fifth-floor counterparts, nineteenth-century physicists are often caricatured as having oversold their grasp on nature’s secrets. But longstanding puzzles — puzzles involving chemical spectra and atomic structure rather than blinking ceiling lights — led twentieth-century pioneers like Niels Bohr, Wolfgang Pauli, and Werner Heisenberg to invent a new style of physical theory. As with the formalism of Bobby Alice, mature quantum theories in this tradition were abstract, offering probabilistic predictions for the outcomes of real-world measurements, while remaining agnostic about what it all meant, about what fundamental reality undergirded the description.

From the very beginning, a counter-tradition associated with names like Albert Einstein, Louis de Broglie, and Erwin Schrödinger insisted that quantum models must ultimately capture something (but probably not everything) about the real stuff moving around us. This tradition gave us visions of subatomic entities as lumps of matter vibrating in space, with the sorts of orbital visualizations one first sees in high school chemistry.

But once the various quantum ideas were codified and physicists realized that they worked remarkably well, most research efforts turned away from philosophical agonizing and toward applications. The second generation of quantum theorists, unburdened by revolutionary angst, replaced every part of classical physics with a quantum version. As Max Planck famously wrote, “A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die.” Since this inherited framework works well enough to get new researchers started, the question of what it all means is usually left alone.

Of course, this question is exactly what most non-experts want answered. For past generations, books with titles like The Tao of Physics and Quantum Reality met this demand, with discussions that wildly mixed conventions of scientific reportage with wisdom literature. Even once quantum theories themselves became familiar, interpretations of them were still new enough to be exciting.

Today, even this thrill is gone. We are now in the part of the story where no one can remember what it was like not to have the blinking lights on the ceiling. Despite the origins of quantum theory as an empirical framework — a container flexible enough to wrap around whatever surprises experiments might uncover — its success has led today’s theorists to regard it as fundamental, a base upon which further speculations might be built.

Regaining that old feeling of disorientation now requires some extra steps.

As interlopers in an ongoing turf war, modern explainers of quantum theory must reckon both with arguments like Niels Bohr’s, which emphasize the theory’s limits on knowledge, and with criticisms like Albert Einstein’s, which demand that the theory represent the real world. Sean Carroll’s Something Deeply Hidden pitches itself to both camps. The title stems from an Einstein anecdote. As “a child of four or five years,” Einstein was fascinated by his father’s compass. He concluded, “Something deeply hidden had to be behind things.” Carroll agrees with this, but argues that the world at its roots is quantum. We only need courage to apply that old Einsteinian realism to our quantum universe.

Carroll is a prolific popularizer — alongside his books, his blog, and his Twitter account, he has also recorded three courses of lectures for general audiences, and for the last year has released a weekly podcast. His new book is appealingly didactic, providing a sustained defense of the Many Worlds interpretation of quantum mechanics, first offered by Hugh Everett III as a graduate student in the 1950s. Carroll maintains that Many Worlds is just quantum mechanics, and he works hard to convince us that supporters aren’t merely perverse. In the early days of electrical research, followers of James Clerk Maxwell were called Maxwellians, but today all physicists are Maxwellians. If Carroll’s project pans out, someday we’ll all be Everettians.

Standard applications of quantum theory follow a standard logic. A physical system is prepared in some initial condition, and modeled using a mathematical representation called a “wave function.” Then the system changes in time, and these changes, governed by the Schrödinger equation, are tracked in the system’s wave function. But when we interpret the wave function in order to generate a prediction of what we will observe, we get only probabilities of possible experimental outcomes.

Carroll insists that this quantum recipe isn’t good enough. It may be sufficient if we care only to predict the likelihood of various outcomes for a given experiment, but it gives us no sense of what the world is like. “Quantum mechanics, in the form in which it is currently presented in physics textbooks,” he writes, “represents an oracle, not a true understanding.”

Most of the quantum mysteries live in the process of measurement. Questions of exactly how measurements force determinate outcomes, and of exactly what we sweep under the rug with that bland word “measurement,” are known collectively in quantum lore as the “measurement problem.” Quantum interpretations are distinguished by how they solve this problem. Usually, solutions involve rejecting some key element of common belief. In the Many Worlds interpretation, the key belief we are asked to reject is that of one single world, with one single future.

The version of the Many Worlds solution given to us in Something Deeply Hidden sidesteps the history of the theory in favor of a logical reconstruction. What Carroll enunciates here is something like a quantum minimalism: “There is only one wave function, which describes the entire system we care about, all the way up to the ‘wave function of the universe’ if we’re talking about the whole shebang.”

Putting this another way, Carroll is a realist about the quantum wave function, and suggests that this mathematical object simply is the deep-down thing, while everything else, from particles to planets to people, are merely its downstream effects. (Sorry, people!) The world of our experience, in this picture, is just a tiny sliver of the real one, where all possible outcomes — all outcomes for which the usual quantum recipe assigns a non-zero probability — continue to exist, buried somewhere out of view in the universal wave function. Hence the “Many Worlds” moniker. What we experience as a single world, chock-full of foreclosed opportunities, Many Worlders understand as but one swirl of mist foaming off an ever-breaking wave.

The position of Many Worlds may not yet be common, but neither is it new. Carroll, for his part, is familiar enough with it to be blasé, presenting it in the breezy tone of a man with all the answers. The virtue of his presentation is that whether or not you agree with him, he gives you plenty to consider, including expert glosses on ongoing debates in cosmology and field theory. But Something Deeply Hidden still fails where it matters. “If we train ourselves to discard our classical prejudices, and take the lessons of quantum mechanics at face value,” Carroll writes near the end, “we may eventually learn how to extract our universe from the wave function.”

But shouldn’t it be the other way around? Why should we have to work so hard to “extract our universe from the wave function,” when the wave function itself is an invention of physicists, not the inerrant revelation of some transcendental truth? Interpretations of quantum theory live or die on how well they are able to explain its success, and the most damning criticism of the Many Worlds interpretation is that it’s hard to see how it improves on the standard idea that probabilities in quantum theory are just a way to quantify our expectations about various measurement outcomes.

Carroll argues that, in Many Worlds, probabilities arise from self-locating uncertainty: “You know everything there is to know about the universe, except where you are within it.” During a measurement, “a single world splits into two, and there are now two people where I used to be just one.” “For a brief while, then, there are two copies of you, and those two copies are precisely identical. Each of them lives on a distinct branch of the wave function, but neither of them knows which one it is on.” The job of the physicist is then to calculate the chance that he has ended up on one branch or another — which produces the probabilities of the various measurement outcomes.

If, alongside Carroll, you convince yourself that it is reasonable to suppose that these worlds exist outside our imaginations, you still might conclude, as he does, that “at the end of the day it doesn’t really change how we should go through our lives.” This conclusion comes in a chapter called “The Human Side,” where Carroll also dismisses the possibility that humans might have a role in branching the wave function, or indeed that we have any ultimate agency: “While you might be personally unsure what choice you will eventually make, the outcome is encoded in your brain.” These views are rewarmed arguments from his previous book, The Big Picture, which I reviewed in these pages (“Pop Goes the Physics,” Spring 2017) and won’t revisit here.

Although this book is unlikely to turn doubters of Many Worlds into converts, it is a credit to Carroll that he leaves one with the impression that the doctrine is probably consistent, whether or not it is true. But internal consistency has little power against an idea that feels unacceptable. For doctrines like Many Worlds, with key claims that are in principle unobservable, some of us will always want a way out.

Lee Smolin is one such seeker for whom Many Worlds realism — or “magical realism,” as he likes to call it — is not real enough. In his new book, Einstein’s Unfinished Revolution, Smolin assures us that “however weird the quantum world may be, it need not threaten anyone’s belief in commonsense realism. It is possible to be a realist while living in the quantum universe.” But if you expect “commonsense realism” by the end of his book, prepare for a surprise.

Smolin is less congenial than Carroll, with a brooding vision of his fellow scientists less as fellow travelers and more as members of an “orthodoxy of the unreal,” as Smolin stirringly puts it. Smolin is best known for his role as doomsayer about string theory — his 2006 book The Trouble with Physics functioned as an entertaining jeremiad. But while his books all court drama and are never boring, that often comes at the expense of argumentative care.

Einstein’s Unfinished Revolution can be summarized briefly. Smolin states early on that quantum theory is wrong: It gives probabilities for many and various measurement outcomes, whereas the world of our observation is solid and singular. Nevertheless, quantum theory can still teach us important lessons about nature. For instance, Smolin takes at face value the claim that entangled particles far apart in the universe can communicate information to each other instantaneously, unbounded by the speed of light. This ability of quantum entities to be correlated while separated in space is technically called “nonlocality,” which Smolin enshrines as a fundamental principle. And while he takes inspiration from an existing nonlocal quantum theory, he rejects it for violating other favorite physical principles. Instead, he elects to redo physics from scratch, proposing partial theories that would allow his favored ideals to survive.

This is, of course, an insane act of hubris. But no red line separates the crackpot from the visionary in theoretical physics. Because Smolin presents himself as a man up against the status quo, his books are as much autobiography as popular science, with personality bleeding into intellectual commitments. Smolin’s last popular book, Time Reborn (2013), showed him changing his mind about the nature of time after doing bedtime with his son. This time around, Smolin tells us in the preface about how he came to view the universe as nonlocal:

I vividly recall that when I understood the proof of the theorem, I went outside in the warm afternoon and sat on the steps of the college library, stunned. I pulled out a notebook and immediately wrote a poem to a girl I had a crush on, in which I told her that each time we touched there were electrons in our hands which from then on would be entangled with each other. I no longer recall who she was or what she made of my poem, or if I even showed it to her. But my obsession with penetrating the mystery of nonlocal entanglement, which began that day, has never since left me.

The book never seriously questions whether the arguments for nonlocality should convince us; Smolin’s experience of conviction must stand in for our own. These personal detours are fascinating, but do little to convince skeptics.

Once you start turning the pages of Einstein’s Unfinished Revolution, ideas fly by fast. First, Smolin gives us a tour of the quantum fundamentals — entanglement, nonlocality, and all that. Then he provides a thoughtful overview of solutions to the measurement problem, particularly those of David Bohm, whose complex legacy he lingers over admiringly. But by the end, Smolin abandons the plodding corporate truth of the scientist for the hope of a private perfection.

Many physicists have never heard of Bohm’s theory, and some who have still conclude that it’s worthless. Bohm attempted to salvage something like the old classical determinism, offering a way to understand measurement outcomes as caused by the motion of particles, which in turn are guided by waves. This conceptual simplicity comes at the cost of brazen nonlocality, and an explicit dualism of particles and waves. Einstein called the theory a “physical fairy-tale for children”; Robert Oppenheimer declared about Bohm that “we must agree to ignore him.”

Bohm’s theory is important to Smolin mainly as a prototype, to demonstrate that it’s possible to situate quantum mechanics within a single world — unlike Many Worlds, which Smolin seems to dislike less for physical than for ethical reasons: “It seems to me that the Many Worlds Interpretation offers a profound challenge to our moral thinking because it erases the distinction between the possible and the actual.” In his survey, Smolin sniffs each interpretation as he passes it, looking for a whiff of the real quantum story, which will preserve our single universe while also maintaining the virtues of all the partial successes.

When Smolin finally explains his own idiosyncratic efforts, his methods — at least in the version he has dramatized here — resemble some wild descendant of Cartesian rationalism. From his survey, Smolin lists the principles he would expect from an acceptable alternative to quantum theory. He then reports back to us on the incomplete models he has found that will support these principles.

Smolin’s tour leads us all over the place, from a review of Leibniz’s Monadology (“shockingly modern”), to a new law of physics he proposes (the “principle of precedence”), to a solution to the measurement problem involving nonlocal interactions among all similar systems everywhere in the universe. Smolin concludes with the grand claim that “the universe consists of nothing but views of itself, each from an event in its history.” Fine. Maybe there’s more to these ideas than a casual reader might glean, but after a few pages of sentences like, “An event is something that happens,” hope wanes.

For all their differences, Carroll and Smolin similarly insist that, once the basic rules governing quantum systems are properly understood, the rest should fall into place. “Once we understand what’s going on for two particles, the generalization to 1088 particles is just math,” Carroll assures us. Smolin is far less certain that physics is on the right track, but he, too, believes that progress will come with theoretical breakthroughs. “I have no better answer than to face the blank notebook,” Smolin writes. This was the path of Bohr, Einstein, Bohm and others. “Ask yourself which of the fundamental principles of the present canon must survive the coming revolution. That’s the first page. Then turn again to a blank page and start thinking.”

Physicists are always tempted to suppose that successful predictions prove that a theory describes how the world really is. And why not? Denying that quantum theory captures something essential about the character of those entities outside our heads that we label with words like “atoms” and “molecules” and “photons” seems far more perverse, as an interpretive strategy, than any of the mainstream interpretations we’ve already discussed. Yet one can admit that something is captured by quantum theory without jumping immediately to the assertion that everything must flow from it. An invented language doesn’t need to be universal to be useful, and it’s smart to keep on honing tools for thinking that have historically worked well.

As an old mentor of mine, John P. Ralston, wrote in his book How to Understand Quantum Mechanics, “We don’t know what nature is, and it is not clear whether quantum theory fully describes it. However, it’s not the worst thing. It has not failed yet.” This seems like the right attitude to take. Quantum theory is a fabulously rich subject, but the fact that it has not failed yet does not allow us to generalize its results indefinitely.

There is value in the exercises that Carroll and Smolin perform, in their attempts to imagine principled and orderly universes, to see just how far one can get with a straitjacketed imagination. But by assuming that everything is captured by the current version of quantum theory, Carroll risks credulity, foreclosing genuinely new possibilities. And by assuming that everything is up for grabs, Smolin risks paranoia, ignoring what is already understood.

Perhaps the agnostics among us are right to settle in as permanent occupants of Reality Industries’ fourth floor. We can accept that scientists have a role in creating stories that make sense, while also appreciating the possibility that the world might not be made of these stories. To the big, unresolved questions — questions about where randomness enters in the measurement process, or about how much of the world our physical theories might capture — we can offer only a laconic who knows? The world is filled with flashing lights, and we should try to find some order in them. Scientific success often involves inventing a language that makes the strange sensible, warping intuitions along the way. And while this process has allowed us to make progress, we should never let our intuitions get so strong that we stop scanning the ceiling for unexpected dazzlements.

David Kordahl is a graduate student in physics at Arizona State University. David Kordahl, “Inventing the Universe,” The New Atlantis, Number 61, Winter 2020, pp. 114-124.