scientificamerican--2020-10-13--Moving in Sync Creates Surprising Social Bonds among People

To save any of his marching bandmates , Steve Marx says , he would run into onrushing traffic with no @ @ @ @ @ kind of language often heard from former army buddies , not musicians , but Marx @ @ @ @ @ show the strength of his feelings about this group .
The marching band director at @ @ @ @ @ been participating in musical ensembles for more than 20 years , since he was in @ @ @ @ @ that “ the sort of bonding that you form is extremely strong .
It 's @ @ @ @ @ is in matching uniforms , musical instruments in hands , marching forward in perfect harmony @ @ @ @ @ leg , movements and sounds so synchronized that individuals blur into the greater group .
@ @ @ @ @ that much about music , he admits .
Marching , for him , is mostly @ @ @ @ @ .

To save any of his marching bandmates, Steve Marx says, he would run into onrushing traffic with no hesitation. It's the kind of language often heard from former army buddies, not musicians, but Marx brings up the scenario to show the strength of his feelings about this group. The marching band director at Gettysburg College in Pennsylvania has been participating in musical ensembles for more than 20 years, since he was in high school, and says that “the sort of bonding that you form is extremely strong. It's like a family.” Everyone is in matching uniforms, musical instruments in hands, marching forward in perfect harmony, left leg, right leg, movements and sounds so synchronized that individuals blur into the greater group. The allure is not even that much about music, he admits. Marching, for him, is mostly about the sense of kinship.
Many group activities boost our sense of belonging, but research shows that doing things synchronously can build even stronger social ties and create a greater sense of well-being. Crew rowing, line dancing, choir singing or simply tapping fingers in sync increases generosity, trust and tolerance toward others, often beyond effects seen in more disorderly doings. It can even increase people's threshold for pain. Why simultaneous, coordinated movement delivers this extra dose of affinity is just now becoming understood, according to Laura Cirelli, a psychologist and synchrony researcher at the University of Toronto. The phenomenon's powerful effects on us result from a combination of neurohormonal, cognitive and perceptual factors. “It's a complicated interplay,” she says. There is also evidence that we have a propensity for synchrony that may have been selected during the course of human evolution, in part because it allows us to bond with large numbers of people at once, offering a survival advantage.
People are not unique in their capability to synchronize activities—certain animals do it as well. Bottlenose dolphins arc through the water in unison, for instance, and males of some firefly species harmonize their flashes. Animal behaviorists theorize that, as with humans, these coordinated behaviors promote various positive social benefits, like attracting a mate. What sets us apart is that our synchrony happens across such a wide variety of behaviors. Some are organized—think of group prayers, chorale singing, military parades and flash mobs. Some are spontaneous—think of concertgoers clapping in time to a song or of a couple strolling through a park, their feet hitting the path at the exact same time. If two people sit in rocking chairs beside each other, studies have shown, they will impulsively start moving back and forth in parallel.
Marx credits synchrony for his devotion to his bandmates, and psychological experiments have shown this kind of coordination does improve group feelings. In one study, researchers at the University of Oxford split young schoolchildren into two groups. One wore orange vests and the other green vests. Such costuming can incite divisions among kids. The experimenters, however, asked the children to spend time dancing together synchronously. Afterward the greens and the oranges bonded more and played closer to each other than similarly divided children who danced in an uncoordinated way.
Performers move as a group for ingoma, a traditional Zulu dance in South Africa. Credit: Rajesh Jantilal Getty Images
Improved affinity
It's not just child's play. A series of experiments in Hungary, published in 2019, suggests that walking in sync with a person from an ethnic minority can reduce prejudice. Negative stereotyping of Roma people is prevalent in Hungary. When researchers asked non-Roma to assign positive or negative words to pictures of traditionally dressed Roma people, they used more negative words. When the same group looked at pictures of traditionally dressed Hungarian people, they used more positive words. Then the investigators asked the non-Roma to walk laps around a large room either in sync or out of sync with someone who was introduced as Roma. When later the researchers asked about the volunteers' feelings toward the Roma, those who engaged in synchrony expressed a greater sense of closeness and indicated more desire to see their partners again.
The scientists do not know how long such effects might last, so coordination may not be a permanent remedy for antagonism. Still, it does appear to minimize bias in some situations, and one possible reason may be because it simply makes us like one another more. In a study published in 2009 in Social Cognition, participants tapped their fingers in rhythm with a metronome and in some instances were joined by an experimenter who drummed either to the same beat or to a different one. Results showed that volunteers who were coordinated with the experimenter were later more inclined to say that they found him likable.
These feelings of affinity translate into more positive behavior toward others. Synchronous finger tapping, for example, can prompt people to be more generous when donating money. In a series of experiments published in 2017 in Basic and Applied Social Psychology, researchers divided volunteers into groups of six, which were then further split into subgroups of three. After members briefly worked together on a group activity, they were given various scenarios for splitting money among themselves and asked to whom they would give. If they then spent time tapping fingers in synchrony with their little trio only, they were more willing to donate money to those people. But if two of these trios tapped in sync—forming a group of six for a few minutes—the members were more likely to donate to all six. Asynchronous tapping, meanwhile, did nothing to boost generosity. A 2017 meta-analysis of 42 studies confirmed that synchronous activities, from running in sync to rocking in chairs at the same pace, prompt people to behave prosocially.
Psychologists and neuroscientists explain the way synchrony draws people together with a dry term: self-other blurring. “It's a weakening of boundaries between self and other. As we become attuned to other people's actions, whether we do it consciously or not, we integrate them with our own,” says Ivana Konvalinka, a cognitive neuroscientist at the Technical University of Denmark.
Even very small children tend to be more helpful after engaging in synchrony. Babies cannot be told to act in sync, of course, so researchers have come up with creative ways to examine the effect. In one experiment published in 2017 in Music Perception, a person had a 14-month-old infant strapped to his or her chest in a baby carrier and another person standing in front of them. Both adults began to bounce, sometimes in perfect synchrony, sometimes not. This made the babies bounce, too. Psychologists conducted a series of experiments using this design. After the in-unison bouncing session, if the second adult dropped a ball or other object, the babies were quite eager to pick it up and hand it back. But those infants who were not bounced in sync were not as helpful. The fact that the effects of synchrony are apparent in such small children suggests this behavior is important to the species, says cognitive anthropologist Emma Cohen of the University of Oxford. “If something is emerging really early in life, then it's likely fairly automatic and really salient for us as humans,” she says. It may even have played an important role in our evolution.
Evolving in unison
Psychologist Robin Dunbar of Oxford believes that by facilitating prosocial behaviors and cooperation, synchrony could have encouraged bonding in groups of early humans as their populations grew. He has been researching synchrony for years, a fascination that started at a conference on the archaeology of music. One of the evening sessions was unusual. A musician from South Africa invited Dunbar and other attendants to participate in something resembling a traditional Zulu dance. He told them to stand in a circle, handed them plastic pipes cut to different lengths and instructed them to blow across the top of the pipes, making random noise, and to start walking around the circle. At first, Dunbar says, the noise was horrible, but after a few minutes the sounds and movements changed without particular effort, the scientists became synchronized, playing music in a consistent tune with one another. “Everybody felt this sense of belonging, being part of the group. I realized this was an amazing effect,” he says.
Dunbar now theorizes that in human evolution synchrony might have enhanced grooming as an important bonding mechanism. Nonhuman primates groom one another to remove fleas and other parasites, and the time spent doing this promotes group cohesion. The activity does take a lot of time and effort as the number of groomed individuals increases, and Dunbar argues that sets an upper limit on the size of a close-knit group. When he plotted the time that various primate species spend grooming one another against their typical group size, it appeared that the two were directly correlated. The upper limit corresponded to a group size of 50 primates. No monkey or ape species forms groups that are, on average, larger, but humans do. Dunbar calculated that a natural community for us stands at about 150 people. He worked out this number based on the size of the human neocortex compared with those of other primates, as well as the populations of villages in small-scale societies and the number of friends and family that people in larger-scale societies tend to have. That figure is borne out in early historical records, too: it was the average village size in England in A.D. 1086 when William the Conqueror surveyed his new kingdom. (Not everyone agrees 150 is a solid number; some scientists have argued it is based on overly selective data.)
One reason early humans may have been able to sustain a group size that is triple that of the average ape, Dunbar suggests, is they came up with a way to “groom” several people at once—using voices or body movements instead of picking parasites with fingers. The larger size offered groups protection against raids by other humans, increasing their ability to survive and reproduce, which in turn allowed for the natural selection of a propensity for synchrony in future generations, Dunbar contends.
The adoption of such behavior often has biological underpinnings. In nonhuman primates grooming triggers the release of neurochemicals called endorphins, which seems to enhance good feelings, Dunbar says. And research suggests that endorphins, which the body produces to reinforce pleasure and relieve pain, might be among the mechanisms that allowed singing and dancing to replace classic grooming in human bonding. Some researchers have called them the “neurochemical glue” of human relationships.
Rowers who train in synchrony have higher levels of endorphins, brain chemicals that blunt pain. Credit: Harald Sund Getty Images
Brains and movement
An endorphin-infused sense of bonding and commitment has been apparent in several experiments, some of them coming from Dunbar's laboratory. One of the early studies showed not only that synchronous behaviors likely trigger the endorphin systems but also that they do so beyond the effects produced by the physical activity itself (the famed “runner's high”). In one of Dunbar's studies, male athletes from the University of Oxford Boat Club were invited to train on rowing machines independently and then work out in synchrony. After the exercise, researchers measured how much pain each of the rowers could take by inflating blood pressure cuffs on their arms until they could no longer take the discomfort. (Measuring endorphin levels directly is difficult, so brief pain perception is commonly used as a proxy.) Dunbar and his colleagues learned that athletes who exercised in sync with others were much more resistant to pain afterwards, and the scientists calculated their endorphin output basically doubled.
A similar series of experiments showed that when it comes to dancing, synchrony boosts endorphin effects far more than do dissonant moves around the floor. Volunteers were first taught some basic dance moves such as “driving” (one hand is extended as if resting on top of a steering wheel, crossing from left to right and back, while the other hand hangs relaxed along the body) or “swimming” (knees bending rhythmically, arms alternating from side to side as if doing the front crawl). Afterward, the participants were divided into groups of four and went onto the dance floor, where everyone was handed headphones through which music would flow. The trick, though, was that in some groups all four volunteers heard exactly the same music and were instructed to do the same movement routine, causing synchrony. But in other foursomes, the members heard different tunes or were instructed to do different routines—causing a weird, discordant silent disco. After the dancing was over, the blood pressure cuffs came out, and the measurements began. Once again, those who engaged in synchrony proved more resistant to pain, confirming that the effects are not merely caused by dancing with others but by dancing with others in synchrony. The scientists behind the experiments, which were published in 2016 in Evolution and Human Behavior, also checked how well the participants bonded. As in other studies of emotional reactions, those who boogied in sync said they felt closer to the other participants than did those who danced separately.
Although endorphins offer a neurochemical explanation for synchrony's powerful effects, other biological mechanisms may be at play, too. When it comes to activity patterns within the brain, synchrony seems to prompt different effects than does humming or shimmying without harmony. A 2020 study using functional near-infrared spectroscopy—a noninvasive technique that measures how much oxygen a particular brain region is using, which indicates how hard it is working—showed that while nonsynchronous movements mostly activate just the left hemisphere of the brain, synchrony involves activation of both the left and right hemispheres. This suggests that synchrony is a far more complex behavior than simpler movements.
Coordinated Rewards
Other research suggests that the brain's reward system, including the neural structures involved in desire and motivation, also plays a role in the power of synchrony by creating a positive feedback loop. Using functional magnetic resonance imaging—another way to gauge brain activity—a series of experiments revealed that for those who find drumming easy, doing it in sync hikes activity in the right caudate, a reward-related area, which in turn makes people more likely to help the person they drummed with. “We believe that during synchronized drumming, the caudate activity reflects the rewarding nature of the experience,” says Christian Keysers, a neuroscientist at the Netherlands Institute for Neuroscience and the study's lead author. “Participants will then be more likely to engage in joint actions with that person in the future.” People synchronize, our reward areas of the brain activate, and that pushes us to do more to help our partners.
Although not everyone experiences the effects of synchrony with equal force, the experience of moving in rhythm with others or of harmonizing voices appears to play an important role in human societies. That is likely why we see synchrony all over, in large symphony concerts, in dance parties and in village ceremonial performances. When we are in sync, our hormones and our brain activity help to smooth societal wrinkles, keeping us together. Joining a marching band may not be the path to world peace, but behavior like it may help make us more tolerant and better able to see the greater good in wider communities.


scientificamerican--2020-10-13--Do We Live in a Simulation? Chances Are about 50–50

It is not often that a comedian gives an astrophysicist goose bumps when discussing the laws of physics .
But comic Chuck Nice managed to do just that in a recent episode of the podcast StarTalk .
The show ’ s host Neil deGrasse Tyson had just explained the simulation argument—the idea that we could be virtual beings living in a computer simulation .
If so , the simulation would most likely create perceptions of reality on demand rather than simulate all of reality all the time—much like a video game optimized to render only the parts of a scene @ @ @ @ @ @ @ that ’ s why we can ’ t travel faster than the speed of light , because if we could , we ’ d be able to get to another galaxy , ” said Nice , the show ’ s co-host , prompting Tyson to gleefully interrupt .
“ Before they can program it , ” the astrophysicist said , delighting at the thought .
“ So the programmer put in that limit.
” Such conversations may seem flippant .
But ever since Nick Bostrom of the University of Oxford wrote a seminal @ @ @ @ @ @ @ , philosophers , physicists , technologists and , yes , comedians have been grappling with the idea of our reality being a simulacrum .
Some have tried to identify ways in which we can discern if we are simulated beings .
Others have attempted to calculate the chance of us being virtual entities .
Now a new analysis shows that the odds that we are living in base reality—meaning an existence that is not simulated—are pretty much even .
But the study also demonstrates that if humans were to ever develop the ability @ @ @ @ @ @ @ would overwhelmingly tilt in favor of us , too , being virtual denizens inside someone else ’ s computer .
( A caveat to that conclusion is that there is little agreement about what the term “ consciousness ” means , let alone how one might go about simulating it . )
In 2003 Bostrom imagined a technologically adept civilization that possesses immense computing power and needs a fraction of that power to simulate new realities with conscious beings in them .
Given this scenario , his simulation argument showed that at least @ @ @ @ @ @ @ be true : First , humans almost always go extinct before reaching the simulation-savvy stage .
Second , even if humans make it to that stage , they are unlikely to be interested in simulating their own ancestral past .
And third , the probability that we are living in a simulation is close to one .
Before Bostrom , the movie The Matrix had already done its part to popularize the notion of simulated realities .
And the idea has deep roots in Western and Eastern philosophical traditions , from Plato ’ @ @ @ @ @ @ @ s butterfly dream .
More recently , Elon Musk gave further fuel to the concept that our reality is a simulation : “ The odds that we are in base reality is one in billions , ” he said at a 2016 conference .
“ Musk is right if you assume [ propositions ] one and two of the trilemma are false , ” says astronomer David Kipping of Columbia University .
“ How can you assume that ?
” To get a better handle on Bostrom ’ s simulation argument , Kipping @ @ @ @ @ @ @ This type of analysis uses Bayes ’ s theorem , named after Thomas Bayes , an 18th-century English statistician and minister .
Bayesian analysis allows one to calculate the odds of something happening ( called the “ posterior ” probability ) by first making assumptions about the thing being analyzed ( assigning it a “ prior ” probability ) .
Kipping began by turning the trilemma into a dilemma .
He collapsed propositions one and two into a single statement , because in both cases , the final outcome is that there are @ @ @ @ @ @ @ pits a physical hypothesis ( there are no simulations ) against the simulation hypothesis ( there is a base reality—and there are simulations , too ) .
“ You just assign a prior probability to each of these models , ” Kipping says .
“ We just assume the principle of indifference , which is the default assumption when you don ’ t have any data or leanings either way.
” So each hypothesis gets a prior probability of one half , much as if one were to flip a coin to decide @ @ @ @ @ @ @ the analysis required thinking about “ parous ” realities—those that can generate other realities—and “ nulliparous ” realities—those that can not simulate offspring realities .
If the physical hypothesis was true , then the probability that we were living in a nulliparous universe would be easy to calculate : it would be 100 percent .
Kipping then showed that even in the simulation hypothesis , most of the simulated realities would be nulliparous .
That is because as simulations spawn more simulations , the computing resources available to each subsequent generation dwindles to @ @ @ @ @ @ @ realities will be those that do not have the computing power necessary to simulate offspring realities that are capable of hosting conscious beings .
Plug all these into a Bayesian formula , and out comes the answer : the posterior probability that we are living in base reality is almost the same as the posterior probability that we are a simulation—with the odds tilting in favor of base reality by just a smidgen .
These probabilities would change dramatically if humans created a simulation with conscious beings inside it , because such an @ @ @ @ @ @ @ previously assigned to the physical hypothesis .
“ You can just exclude that [ hypothesis ] right off the bat .
Then you are only left with the simulation hypothesis , ” Kipping says .
“ The day we invent that technology , it flips the odds from a little bit better than 50–50 that we are real to almost certainly we are not real , according to these calculations .
It ’ d be a very strange celebration of our genius that day.
” The upshot of Kipping ’ s analysis is @ @ @ @ @ @ @ is wrong about the one-in-billions odds that he ascribes to us living in base reality .
Bostrom agrees with the result—with some caveats .
“ This does not conflict with the simulation argument , which only asserts something about the disjunction , ” the idea that one of the three propositions of the trilemma is true , he says .
But Bostrom takes issue with Kipping ’ s choice to assign equal prior probabilities to the physical and simulation hypothesis at the start of the analysis .
“ The invocation of the principle @ @ @ @ @ @ @ ” he says .
“ One could equally well invoke it over my original three alternatives , which would then give them one-third chance each .
Or one could carve up the possibility space in some other manner and get any result one wishes.
” Such quibbles are valid because there is no evidence to back one claim over the others .
That situation would change if we can find evidence of a simulation .
So could you detect a glitch in the Matrix ?
Houman Owhadi , an expert on computational mathematics @ @ @ @ @ @ @ has thought about the question .
“ If the simulation has infinite computing power , there is no way you ’ re going to see that you ’ re living in a virtual reality , because it could compute whatever you want to the degree of realism you want , ” he says .
“ If this thing can be detected , you have to start from the principle that [ it has ] limited computational resources.
” Think again of video games , many of which rely on clever programming to minimize @ @ @ @ @ @ @ world .
For Owhadi , the most promising way to look for potential paradoxes created by such computing shortcuts is through quantum physics experiments .
Quantum systems can exist in a superposition of states , and this superposition is described by a mathematical abstraction called the wave function .
In standard quantum mechanics , the act of observation causes this wave function to randomly collapse to one of many possible states .
Physicists are divided over whether the process of collapse is something real or just reflects a change in our knowledge about @ @ @ @ @ @ @ just a pure simulation , there is no collapse , ” Owhadi says .
“ Everything is decided when you look at it .
The rest is just simulation , like when you ’ re playing these video games.
” To this end , Owhadi and his colleagues have worked on five conceptual variations of the double-slit experiment , each designed to trip up a simulation .
But he acknowledges that it is impossible to know , at this stage , if such experiments could work .
“ Those five experiments are just @ @ @ @ @ @ @ Davoudi , a physicist at the University of Maryland , College Park , has also entertained the idea that a simulation with finite computing resources could reveal itself .
Her work focuses on strong interactions , or the strong nuclear force—one of nature ’ s four fundamental forces .
The equations describing strong interactions , which hold together quarks to form protons and neutrons , are so complex that they can not be solved analytically .
To understand strong interactions , physicists are forced to do numerical simulations .
And unlike any putative @ @ @ @ @ @ @ must rely on shortcuts to make those simulations computationally viable—usually by considering spacetime to be discrete rather than continuous .
The most advanced result researchers have managed to coax from this approach so far is the simulation of a single nucleus of helium that is composed of two protons and two neutrons .
“ Naturally , you start to ask , if you simulated an atomic nucleus today , maybe in 10 years , we could do a larger nucleus ; maybe in 20 or 30 years , we could do a molecule @ @ @ @ @ @ @ 50 years , who knows , maybe you can do something the size of a few inches of matter .
Maybe in 100 years or so , we can do the [ human ] brain.
” Davoudi thinks that classical computers will soon hit a wall , however .
“ In the next maybe 10 to 20 years , we will actually see the limits of our classical simulations of the physical systems , ” she says .
Thus , she is turning her sights to quantum computation , which relies on superpositions @ @ @ @ @ @ @ certain computational problems that would be impossible through classical approaches .
“ If quantum computing actually materializes , in the sense that it ’ s a large scale , reliable computing option for us , then we ’ re going to enter a completely different era of simulation , ” Davoudi says .
“ I am starting to think about how to perform my simulations of strong interaction physics and atomic nuclei if I had a quantum computer that was viable.
” All of these factors have led Davoudi to speculate about the @ @ @ @ @ @ @ a simulation , then the simulator is likely also discretizing spacetime to save on computing resources ( assuming , of course , that it is using the same mechanisms as our physicists for that simulation ) .
Signatures of such discrete spacetime could potentially be seen in the directions high-energy cosmic rays arrive from : they would have a preferred direction in the sky because of the breaking of so-called rotational symmetry .
Telescopes “ haven ’ t observed any deviation from that rotational invariance yet , ” Davoudi says .
And even @ @ @ @ @ @ @ seen , it would not constitute unequivocal evidence that we live in a simulation .
Base reality itself could have similar properties .
Kipping , despite his own study , worries that further work on the simulation hypothesis is on thin ice .
“ It ’ s arguably not testable as to whether we live in a simulation or not , ” he says .
“ If it ’ s not falsifiable , then how can you claim it ’ s really science ?
” For him , there is a more obvious @ @ @ @ @ @ @ which says that in the absence of other evidence , the simplest explanation is more likely to be correct .
The simulation hypothesis is elaborate , presuming realities nested upon realities , as well as simulated entities that can never tell that they are inside a simulation .
“ Because it is such an overly complicated , elaborate model in the first place , by Occam ’ s razor , it really should be disfavored , compared to the simple natural explanation , ” Kipping says .
Maybe we are living in base @ @ @ @ @ @ @ weird quantum physics notwithstanding .

It is not often that a comedian gives an astrophysicist goose bumps when discussing the laws of physics. But comic Chuck Nice managed to do just that in a recent episode of the podcast StarTalk. The show’s host Neil deGrasse Tyson had just explained the simulation argument—the idea that we could be virtual beings living in a computer simulation. If so, the simulation would most likely create perceptions of reality on demand rather than simulate all of reality all the time—much like a video game optimized to render only the parts of a scene visible to a player. “Maybe that’s why we can’t travel faster than the speed of light, because if we could, we’d be able to get to another galaxy,” said Nice, the show’s co-host, prompting Tyson to gleefully interrupt. “Before they can program it,” the astrophysicist said, delighting at the thought. “So the programmer put in that limit.”
Such conversations may seem flippant. But ever since Nick Bostrom of the University of Oxford wrote a seminal paper about the simulation argument in 2003, philosophers, physicists, technologists and, yes, comedians have been grappling with the idea of our reality being a simulacrum. Some have tried to identify ways in which we can discern if we are simulated beings. Others have attempted to calculate the chance of us being virtual entities. Now a new analysis shows that the odds that we are living in base reality—meaning an existence that is not simulated—are pretty much even. But the study also demonstrates that if humans were to ever develop the ability to simulate conscious beings, the chances would overwhelmingly tilt in favor of us, too, being virtual denizens inside someone else’s computer. (A caveat to that conclusion is that there is little agreement about what the term “consciousness” means, let alone how one might go about simulating it.)
In 2003 Bostrom imagined a technologically adept civilization that possesses immense computing power and needs a fraction of that power to simulate new realities with conscious beings in them. Given this scenario, his simulation argument showed that at least one proposition in the following trilemma must be true: First, humans almost always go extinct before reaching the simulation-savvy stage. Second, even if humans make it to that stage, they are unlikely to be interested in simulating their own ancestral past. And third, the probability that we are living in a simulation is close to one.
Before Bostrom, the movie The Matrix had already done its part to popularize the notion of simulated realities. And the idea has deep roots in Western and Eastern philosophical traditions, from Plato’s cave allegory to Zhuang Zhou’s butterfly dream. More recently, Elon Musk gave further fuel to the concept that our reality is a simulation: “The odds that we are in base reality is one in billions,” he said at a 2016 conference.
“Musk is right if you assume [propositions] one and two of the trilemma are false,” says astronomer David Kipping of Columbia University. “How can you assume that?”
To get a better handle on Bostrom’s simulation argument, Kipping decided to resort to Bayesian reasoning. This type of analysis uses Bayes’s theorem, named after Thomas Bayes, an 18th-century English statistician and minister. Bayesian analysis allows one to calculate the odds of something happening (called the “posterior” probability) by first making assumptions about the thing being analyzed (assigning it a “prior” probability).
Kipping began by turning the trilemma into a dilemma. He collapsed propositions one and two into a single statement, because in both cases, the final outcome is that there are no simulations. Thus, the dilemma pits a physical hypothesis (there are no simulations) against the simulation hypothesis (there is a base reality—and there are simulations, too). “You just assign a prior probability to each of these models,” Kipping says. “We just assume the principle of indifference, which is the default assumption when you don’t have any data or leanings either way.”
So each hypothesis gets a prior probability of one half, much as if one were to flip a coin to decide a wager.
The next stage of the analysis required thinking about “parous” realities—those that can generate other realities—and “nulliparous” realities—those that cannot simulate offspring realities. If the physical hypothesis was true, then the probability that we were living in a nulliparous universe would be easy to calculate: it would be 100 percent. Kipping then showed that even in the simulation hypothesis, most of the simulated realities would be nulliparous. That is because as simulations spawn more simulations, the computing resources available to each subsequent generation dwindles to the point where the vast majority of realities will be those that do not have the computing power necessary to simulate offspring realities that are capable of hosting conscious beings.
Plug all these into a Bayesian formula, and out comes the answer: the posterior probability that we are living in base reality is almost the same as the posterior probability that we are a simulation—with the odds tilting in favor of base reality by just a smidgen.
These probabilities would change dramatically if humans created a simulation with conscious beings inside it, because such an event would change the chances that we previously assigned to the physical hypothesis. “You can just exclude that [hypothesis] right off the bat. Then you are only left with the simulation hypothesis,” Kipping says. “The day we invent that technology, it flips the odds from a little bit better than 50–50 that we are real to almost certainly we are not real, according to these calculations. It’d be a very strange celebration of our genius that day.”
The upshot of Kipping’s analysis is that, given current evidence, Musk is wrong about the one-in-billions odds that he ascribes to us living in base reality. Bostrom agrees with the result—with some caveats. “This does not conflict with the simulation argument, which only asserts something about the disjunction,” the idea that one of the three propositions of the trilemma is true, he says.
But Bostrom takes issue with Kipping’s choice to assign equal prior probabilities to the physical and simulation hypothesis at the start of the analysis. “The invocation of the principle of indifference here is rather shaky,” he says. “One could equally well invoke it over my original three alternatives, which would then give them one-third chance each. Or one could carve up the possibility space in some other manner and get any result one wishes.”
Such quibbles are valid because there is no evidence to back one claim over the others. That situation would change if we can find evidence of a simulation. So could you detect a glitch in the Matrix?
Houman Owhadi, an expert on computational mathematics at the California Institute of Technology, has thought about the question. “If the simulation has infinite computing power, there is no way you’re going to see that you’re living in a virtual reality, because it could compute whatever you want to the degree of realism you want,” he says. “If this thing can be detected, you have to start from the principle that [it has] limited computational resources.” Think again of video games, many of which rely on clever programming to minimize the computation required to construct a virtual world.
For Owhadi, the most promising way to look for potential paradoxes created by such computing shortcuts is through quantum physics experiments. Quantum systems can exist in a superposition of states, and this superposition is described by a mathematical abstraction called the wave function. In standard quantum mechanics, the act of observation causes this wave function to randomly collapse to one of many possible states. Physicists are divided over whether the process of collapse is something real or just reflects a change in our knowledge about the system. “If it is just a pure simulation, there is no collapse,” Owhadi says. “Everything is decided when you look at it. The rest is just simulation, like when you’re playing these video games.”
To this end, Owhadi and his colleagues have worked on five conceptual variations of the double-slit experiment, each designed to trip up a simulation. But he acknowledges that it is impossible to know, at this stage, if such experiments could work. “Those five experiments are just conjectures,” Owhadi says.
Zohreh Davoudi, a physicist at the University of Maryland, College Park, has also entertained the idea that a simulation with finite computing resources could reveal itself. Her work focuses on strong interactions, or the strong nuclear force—one of nature’s four fundamental forces. The equations describing strong interactions, which hold together quarks to form protons and neutrons, are so complex that they cannot be solved analytically. To understand strong interactions, physicists are forced to do numerical simulations. And unlike any putative supercivilizations possessing limitless computing power, they must rely on shortcuts to make those simulations computationally viable—usually by considering spacetime to be discrete rather than continuous. The most advanced result researchers have managed to coax from this approach so far is the simulation of a single nucleus of helium that is composed of two protons and two neutrons.
“Naturally, you start to ask, if you simulated an atomic nucleus today, maybe in 10 years, we could do a larger nucleus; maybe in 20 or 30 years, we could do a molecule,” Davoudi says. “In 50 years, who knows, maybe you can do something the size of a few inches of matter. Maybe in 100 years or so, we can do the [human] brain.”
Davoudi thinks that classical computers will soon hit a wall, however. “In the next maybe 10 to 20 years, we will actually see the limits of our classical simulations of the physical systems,” she says. Thus, she is turning her sights to quantum computation, which relies on superpositions and other quantum effects to make tractable certain computational problems that would be impossible through classical approaches. “If quantum computing actually materializes, in the sense that it’s a large scale, reliable computing option for us, then we’re going to enter a completely different era of simulation,” Davoudi says. “I am starting to think about how to perform my simulations of strong interaction physics and atomic nuclei if I had a quantum computer that was viable.”
All of these factors have led Davoudi to speculate about the simulation hypothesis. If our reality is a simulation, then the simulator is likely also discretizing spacetime to save on computing resources (assuming, of course, that it is using the same mechanisms as our physicists for that simulation). Signatures of such discrete spacetime could potentially be seen in the directions high-energy cosmic rays arrive from: they would have a preferred direction in the sky because of the breaking of so-called rotational symmetry.
Telescopes “haven’t observed any deviation from that rotational invariance yet,” Davoudi says. And even if such an effect were to be seen, it would not constitute unequivocal evidence that we live in a simulation. Base reality itself could have similar properties.
Kipping, despite his own study, worries that further work on the simulation hypothesis is on thin ice. “It’s arguably not testable as to whether we live in a simulation or not,” he says. “If it’s not falsifiable, then how can you claim it’s really science?”
For him, there is a more obvious answer: Occam’s razor, which says that in the absence of other evidence, the simplest explanation is more likely to be correct. The simulation hypothesis is elaborate, presuming realities nested upon realities, as well as simulated entities that can never tell that they are inside a simulation. “Because it is such an overly complicated, elaborate model in the first place, by Occam’s razor, it really should be disfavored, compared to the simple natural explanation,” Kipping says.
Maybe we are living in base reality after all—The Matrix, Musk and weird quantum physics notwithstanding.


scientificamerican--2020-10-13--Magic Is (Literally) for the Birds

Magic Is (Literally) for the Birds

The magician climbs into the cage to perform a show for one .
For this special event , he eschews coins and cards for peanuts .
He rolls his sleeves and faces his captive audience : a corvid bird by the name of Stuka .
He shows Stuka a peanut and waves it through the air , sweeping it from one hand to another .
Stuka tracks the treat , moving its head like a spectator at a tennis match .
Then the magician opens his right hand and shows … nothing !
The nut has disappeared !
Stuka seems @ @ @ @ @ @ @ , but the magician pulls it from inside his mouth .
Was it there all along ?
Now the magician vanishes the peanut again , pulling it from his ear next .
The peanut keeps magically switching from one place to another , and a second bird approaches to watch , perhaps out of curiosity .
The question is , what are those birdbrains thinking ?
Elias Garcia-Pelegrin learned to perform magic as an undergraduate student studying drama at University College London ( UCL ) .
Upon graduating—and realizing that acting wouldn ’ @ @ @ @ @ @ @ bar magician .
He also took a job as a zookeeper in an aquarium and grew fascinated with the possible role of social transmission in the mating rituals of penguins .
By then , he had gone back to college for a second degree in psychology .
Now a Ph.D. student at the University of Cambridge , Garcia-Pelegrin is set to apply his multifaceted background in psychology , zoology and magic to the study of animal cognition .
Garcia-Pelegrin 's approach , presented in a recent Science perspective co-authored by Alexandra Schnell , @ @ @ @ @ @ @ , follows in the footsteps of research deploying visual illusions to better understand perception in such disparate species as lions , horses , monkeys and bees .
Their framework also extends prior explorations of the intersection of magic , psychology and neuroscience in subjects ranging from human audiences to nonhuman minds .
Since the late 2000s , cognitive scientists increasingly have exploited magic tricks to delve into the human psyche , sometimes in explicit partnership with professional magicians .
One example is the Magic of Consciousness Symposium in 2007 , which brought together @ @ @ @ @ @ @ Apollo Robbins and James Randi , and led to a joint academic article proposing collaboration between both spheres .
In 2008 , a follow-up article in Scientific American coined the word neuromagic to describe the nascent field of enquiry .
Dozens of research papers using magic to explore human perception and cognition have been published in the intervening years .
The foundations for probing animal minds with magic are solid , given the abundant evidence of misdirection and deception in many species .
For instance , chimpanzees look away from desired objects to @ @ @ @ @ @ @ corvids ) protect their food caches by pretending to store food in bogus locations .
There is also reason to believe that animals can be fooled by human trickery .
Animal scientists occasionally use techniques related to magic to investigate cognition , such as invisible string—used for levitation effects—or the shell game .
However , it is important to consider species-specific behavior , warns animal cognition expert Irene Pepperberg .
Because parrots don ’ t store food , experiments having to do with episodic memory and caching behavior make little sense in parrots @ @ @ @ @ @ @ permanence there is as much work on parrots as there is on corvids , ” Pepperberg says .
Viral YouTube videos also feature sleight-of-hand demonstrations by human conjurers to dogs , chimps and baboons , spurring emotions that seem to range from amusement to annoyance .
If you have ever played a game of fetch with your dog , withholding a stick while pretending to throw it , you have performed a rudimentary form of magic , coarsely related to the classical vanishing ball illusion .
Garcia-Pelegrin understands the apparent frustration sometimes expressed @ @ @ @ @ @ @ a typical magic show , the stakes are very low for audience members , ” he says .
“ Even if the magician takes somebody ’ s wallet , that person knows they ’ ll get it back at the end of the show.
” In contrast , when a magician performs for an animal , they may engage attention by handling food ( a high-stakes reward ) that mysteriously appears or disappears .
The social contract that makes magic feel safe to human audiences does not necessary apply to animal spectators .
@ @ @ @ @ @ @ in addition , that nonhuman audiences may be less than enchanted by human magicians .
“ We know that even chimpanzees don ’ t pay the same attention to humans compared to their own species .
This is recognized as the main problem with human-administered tests of chimpanzee cognition .
Perhaps magicians would need to be conspecifics for this method to work ?
This would complicate things considerably , ” he says .
Jamy Ian Swiss , a sleight-of-hand magician , skeptic and wildlife activist , also ponders the unforeseen assumptions that animals @ @ @ @ @ @ @ “ An adult will generally fall for a false transfer like the French drop , but a child witnessing the same false transfer will immediately know where the object is , because they do not make all the assumptions that adults make .
If the bird is operating at a child ’ s level , then it ’ s not going to be making the conventional assumptions [ expected from an adult ] .
” Despite such limitations , Pepperberg thinks that the strategy may produce big returns : “ We get a @ @ @ @ @ @ @ kinds of reactions , ” because they hint at the animals ’ awareness of their own cognition .
So , what is the most important unanswered question in animal cognition this type of research could address ?
“ I would say consciousness , ” Pepperberg says .

Susana Martinez-Conde and Stephen L. Macknik

The magician climbs into the cage to perform a show for one. For this special event, he eschews coins and cards for peanuts. He rolls his sleeves and faces his captive audience: a corvid bird by the name of Stuka. He shows Stuka a peanut and waves it through the air, sweeping it from one hand to another. Stuka tracks the treat, moving its head like a spectator at a tennis match. Then the magician opens his right hand and shows … nothing! The nut has disappeared! Stuka seems to look around for the missing legume, but the magician pulls it from inside his mouth. Was it there all along? Now the magician vanishes the peanut again, pulling it from his ear next. The peanut keeps magically switching from one place to another, and a second bird approaches to watch, perhaps out of curiosity. The question is, what are those birdbrains thinking?
Elias Garcia-Pelegrin learned to perform magic as an undergraduate student studying drama at University College London (UCL). Upon graduating—and realizing that acting wouldn’t pay the bills—he worked as a bar magician. He also took a job as a zookeeper in an aquarium and grew fascinated with the possible role of social transmission in the mating rituals of penguins. By then, he had gone back to college for a second degree in psychology. Now a Ph.D. student at the University of Cambridge, Garcia-Pelegrin is set to apply his multifaceted background in psychology, zoology and magic to the study of animal cognition.
Garcia-Pelegrin's approach, presented in a recent Science perspective co-authored by Alexandra Schnell, Clive Wilkins, and Nicola S. Clayton, follows in the footsteps of research deploying visual illusions to better understand perception in such disparate species as lions, horses, monkeys and bees. Their framework also extends prior explorations of the intersection of magic, psychology and neuroscience in subjects ranging from human audiences to nonhuman minds.
Since the late 2000s, cognitive scientists increasingly have exploited magic tricks to delve into the human psyche, sometimes in explicit partnership with professional magicians. One example is the Magic of Consciousness Symposium in 2007, which brought together neuroscientists and magicians such as Teller, Apollo Robbins and James Randi, and led to a joint academic article proposing collaboration between both spheres. In 2008, a follow-up article in Scientific American coined the word neuromagic to describe the nascent field of enquiry. Dozens of research papers using magic to explore human perception and cognition have been published in the intervening years.
The foundations for probing animal minds with magic are solid, given the abundant evidence of misdirection and deception in many species. For instance, chimpanzees look away from desired objects to thwart possible competitors, and jays (corvids) protect their food caches by pretending to store food in bogus locations.
There is also reason to believe that animals can be fooled by human trickery. Animal scientists occasionally use techniques related to magic to investigate cognition, such as invisible string—used for levitation effects—or the shell game. However, it is important to consider species-specific behavior, warns animal cognition expert Irene Pepperberg. Because parrots don’t store food, experiments having to do with episodic memory and caching behavior make little sense in parrots. “But in terms of object permanence there is as much work on parrots as there is on corvids,” Pepperberg says.
Viral YouTube videos also feature sleight-of-hand demonstrations by human conjurers to dogs, chimps and baboons, spurring emotions that seem to range from amusement to annoyance. If you have ever played a game of fetch with your dog, withholding a stick while pretending to throw it, you have performed a rudimentary form of magic, coarsely related to the classical vanishing ball illusion.
Garcia-Pelegrin understands the apparent frustration sometimes expressed by his unusual audiences. “In a typical magic show, the stakes are very low for audience members,” he says. “Even if the magician takes somebody’s wallet, that person knows they’ll get it back at the end of the show.” In contrast, when a magician performs for an animal, they may engage attention by handling food (a high-stakes reward) that mysteriously appears or disappears. The social contract that makes magic feel safe to human audiences does not necessary apply to animal spectators.
Primatologist Frans de Waal points out, in addition, that nonhuman audiences may be less than enchanted by human magicians. “We know that even chimpanzees don’t pay the same attention to humans compared to their own species. This is recognized as the main problem with human-administered tests of chimpanzee cognition. Perhaps magicians would need to be conspecifics for this method to work? This would complicate things considerably,” he says.
Jamy Ian Swiss, a sleight-of-hand magician, skeptic and wildlife activist, also ponders the unforeseen assumptions that animals might make during a magic performance. “An adult will generally fall for a false transfer like the French drop, but a child witnessing the same false transfer will immediately know where the object is, because they do not make all the assumptions that adults make. If the bird is operating at a child’s level, then it’s not going to be making the conventional assumptions [expected from an adult].”
Despite such limitations, Pepperberg thinks that the strategy may produce big returns: “We get a glimmer of knowledge when we get these kinds of reactions,” because they hint at the animals’ awareness of their own cognition. So, what is the most important unanswered question in animal cognition this type of research could address? “I would say consciousness,” Pepperberg says.


scientificamerican--2020-10-13--Why the World's Biggest Dinosaurs Keep Getting Cut Down to Size

On August 9 , 2017 , paleontologists at the American Museum of Natural History in New York City unveiled the largest animal ever to walk the earth .
Dubbed Patagotitan mayorum , the reconstructed skeleton of the 100-million-year-old dinosaur was so huge that it didn ’ t even fit wholly inside the room in which it stood .
The dinosaur ’ s long neck , bulging body and long tail stretched about 120 feet long , with the living animal estimated to weigh in at more than 70 tons .
But now it ’ s shrunk .
In a new @ @ @ @ @ @ @ representing several individuals of differing ages , paleontologist Alejandro Otero and his colleagues have slimmed down Patagotitan to around 57 tons .
The full length of the dinosaur is in question , too , especially as no complete skeleton is known .
What was heralded as the largest dinosaur of all in 2014 has wound up in a neck-and-neck tie with several other dinosaurian giants such as Argentinosaurus .
The shrinkage comes as part of a long history of supersized dinosaurs that have been downsized after their initial discovery .
Incomplete fossils , @ @ @ @ @ @ @ with enormous dinosaurs have all played into the constant quest to find the biggest creature to walk the planet .
Although many dinosaurs lived large—the famous T. rex was 40 feet long and weighed nine tons—all of the very largest dinosaurs belonged to a group called sauropods .
These quadrupedal herbivores are immediately recognizable by their tiny heads , long necks , hefty bodies and tapering tails .
Dinosaurs such as Brontosaurus and Diplodocus conveyed the standard image of these plant eaters to museumgoers for more than a century .
But even these @ @ @ @ @ @ @ of all .
“ The fact that literally a handful of bones indicates that there truly were terrestrial titans of near mythic proportions leaves us in sheer awe , ” says University of Toronto paleontologist Cary Woodruff .
Not to mention that these dinosaurs are so strange , from the tip of their snouts to the end of their tapering tails .
“ With nothing quite like sauropods today , ” says Macalester College paleontologist Kristi Curry-Rogers , “ our work on these creatures is akin to studying aliens.
” One of the @ @ @ @ @ @ @ herbivore known from a paltry collection of bones uncovered in western Colorado in 1900 .
Even though only about 20 percent of the skeleton was found , comparisons with similar dinosaurs led to estimates that Brachiosaurus was more than 60 feet long and more than 40 feet tall , a giant that towered over the likes of Apatosaurus and Diplodocus .
But there were larger species out there .
The “ great-dinosaur renaissance ” that lasted from the 1970s through the 1990s saw a new bone rush that uncovered several ever larger dinosaurs @ @ @ @ @ @ @ its stature , with “ Ultrasaurus , ” “ Supersaurus , ” “ Seismosaurus , ” and more all making news and documentary appearances as the biggest of the big .
Yet the initial announcements from the field didn ’ t hold up once the fossils were brought back to the lab for study .
In fact , some of the supposed giants—such as Ultrasaurus—turned out to be misidentified representatives of other species and not quite so exceptional as originally thought .
And then there are the lost giants .
Part of a @ @ @ @ @ @ @ Cope in the 19th century seemed to suggest a sauropod , known as Amphicoelias , that measured almost twice as long as any other .
The problem is that the bone was mysteriously lost , and no other example has turned up over more than a century of fossil expeditions .
Likewise a dinosaur from India named Bruhathkayosaurus was rumored to be the largest , but those fossils disintegrated and are no longer available to study .
Even among the giants that paleontologists have in hand , determining the winner is challenging .
@ @ @ @ @ @ @ of the largest dinosaur skeletons are incomplete .
“ When we imagine how unlikely it is for an entire adult sauropod skeleton to overcome the vagaries of the fossil record , it ’ s not at all surprising that complete specimens are hard to come by , ” Curry-Rogers says .
A huge amount of sediment was needed to bury the bodies , which were often ravaged by scavengers before burial .
Add different analytic methodologies to the mix , and experts often have to revise their expectations .
“ Another huge problem @ @ @ @ @ @ @ issue of exactly what is being measured or estimated , ” she says , especially as some longer dinosaurs might be lighter than heavier , shorter dinosaurs , meaning there ’ s no single metric to determine a winner .
“ We all can step on a scale today , but how do we weigh something that can not be traditionally weighed ?
” Woodruff says .
Paleontologists have tried a variety of methods , from dunking plastic models in water to estimate a dinosaur ’ s volume to looking at the relation @ @ @ @ @ @ @ bones to mass .
Experts continue to compare and refine techniques , and one study published earlier this year found that different techniques are finding similar results .
Over time , estimations of dinosaur size are becoming more refined and falling into accord with each other .
New realizations can change experts ’ expectations , too .
When paleontologists realized that the vertebrae of sauropods were filled with air sacs to keep them light , she notes , paleontologists had to adjust how they determine mass .
“ With more knowledge , whether @ @ @ @ @ @ @ for comparison or better fossils , comes more precision , ” Curry-Rogers says .
But how to determine a winner ?
Various methods might find a difference of a few tons in sauropod size estimates .
That ’ s a large mass for humans , Woodruff says , but “ for an animal already weighing 30 to 40 tons , that ’ s not a terribly dramatic difference.
” Still , those variations will likely only keep fueling the persistent quest to identify the largest animal of all .
As Woodruff says , @ @ @ @ @ @ @

On August 9, 2017, paleontologists at the American Museum of Natural History in New York City unveiled the largest animal ever to walk the earth. Dubbed Patagotitan mayorum, the reconstructed skeleton of the 100-million-year-old dinosaur was so huge that it didn’t even fit wholly inside the room in which it stood. The dinosaur’s long neck, bulging body and long tail stretched about 120 feet long, with the living animal estimated to weigh in at more than 70 tons. But now it’s shrunk.
In a new study of the available Patagotitan fossils, representing several individuals of differing ages, paleontologist Alejandro Otero and his colleagues have slimmed down Patagotitan to around 57 tons. The full length of the dinosaur is in question, too, especially as no complete skeleton is known. What was heralded as the largest dinosaur of all in 2014 has wound up in a neck-and-neck tie with several other dinosaurian giants such as Argentinosaurus. The shrinkage comes as part of a long history of supersized dinosaurs that have been downsized after their initial discovery. Incomplete fossils, evolving techniques, and the paleontological preoccupation with enormous dinosaurs have all played into the constant quest to find the biggest creature to walk the planet.
Although many dinosaurs lived large—the famous T. rex was 40 feet long and weighed nine tons—all of the very largest dinosaurs belonged to a group called sauropods. These quadrupedal herbivores are immediately recognizable by their tiny heads, long necks, hefty bodies and tapering tails. Dinosaurs such as Brontosaurus and Diplodocus conveyed the standard image of these plant eaters to museumgoers for more than a century. But even these enormous animals weren’t the largest of all.
“The fact that literally a handful of bones indicates that there truly were terrestrial titans of near mythic proportions leaves us in sheer awe,” says University of Toronto paleontologist Cary Woodruff. Not to mention that these dinosaurs are so strange, from the tip of their snouts to the end of their tapering tails. “With nothing quite like sauropods today,” says Macalester College paleontologist Kristi Curry-Rogers, “our work on these creatures is akin to studying aliens.”
One of the first front-runners was Brachiosaurus, a long-necked herbivore known from a paltry collection of bones uncovered in western Colorado in 1900. Even though only about 20 percent of the skeleton was found, comparisons with similar dinosaurs led to estimates that Brachiosaurus was more than 60 feet long and more than 40 feet tall, a giant that towered over the likes of Apatosaurus and Diplodocus.
But there were larger species out there. The “great-dinosaur renaissance” that lasted from the 1970s through the 1990s saw a new bone rush that uncovered several ever larger dinosaurs. Each was given a name befitting its stature, with “Ultrasaurus,” “Supersaurus,” “Seismosaurus,” and more all making news and documentary appearances as the biggest of the big. Yet the initial announcements from the field didn’t hold up once the fossils were brought back to the lab for study. In fact, some of the supposed giants—such as Ultrasaurus—turned out to be misidentified representatives of other species and not quite so exceptional as originally thought.
And then there are the lost giants. Part of a backbone described by fossil hunter E. D. Cope in the 19th century seemed to suggest a sauropod, known as Amphicoelias, that measured almost twice as long as any other. The problem is that the bone was mysteriously lost, and no other example has turned up over more than a century of fossil expeditions. Likewise a dinosaur from India named Bruhathkayosaurus was rumored to be the largest, but those fossils disintegrated and are no longer available to study.
Even among the giants that paleontologists have in hand, determining the winner is challenging. Part of the problem is that many of the largest dinosaur skeletons are incomplete. “When we imagine how unlikely it is for an entire adult sauropod skeleton to overcome the vagaries of the fossil record, it’s not at all surprising that complete specimens are hard to come by,” Curry-Rogers says. A huge amount of sediment was needed to bury the bodies, which were often ravaged by scavengers before burial. Add different analytic methodologies to the mix, and experts often have to revise their expectations. “Another huge problem, no pun intended, is the issue of exactly what is being measured or estimated,” she says, especially as some longer dinosaurs might be lighter than heavier, shorter dinosaurs, meaning there’s no single metric to determine a winner.
“We all can step on a scale today, but how do we weigh something that cannot be traditionally weighed?” Woodruff says. Paleontologists have tried a variety of methods, from dunking plastic models in water to estimate a dinosaur’s volume to looking at the relation between the circumference of thigh and upper-arm bones to mass. Experts continue to compare and refine techniques, and one study published earlier this year found that different techniques are finding similar results. Over time, estimations of dinosaur size are becoming more refined and falling into accord with each other.
New realizations can change experts’ expectations, too. When paleontologists realized that the vertebrae of sauropods were filled with air sacs to keep them light, she notes, paleontologists had to adjust how they determine mass. “With more knowledge, whether in the form of better living models for comparison or better fossils, comes more precision,” Curry-Rogers says.
But how to determine a winner? Various methods might find a difference of a few tons in sauropod size estimates. That’s a large mass for humans, Woodruff says, but “for an animal already weighing 30 to 40 tons, that’s not a terribly dramatic difference.” Still, those variations will likely only keep fueling the persistent quest to identify the largest animal of all. As Woodruff says, “everyone likes a winner.”


scientificamerican--2020-10-13--Play Helped Dogs Be Our Best Friends

Play Helped Dogs Be Our Best Friends

All domestic dogs belong to a single species that descended from wolves—despite vast differences in size , appearance , behavior and temperament among breeds .
While dogs first became domesticated tens of thousands of years ago , the breeds we know today are largely the result of selection for certain traits by humans over the past several hundred years .
“ We have an enormous amount of diversity within the same species , and we can rarely observe such diversity in nature .
So , it 's a wonderful system to understand how evolution works within a short period of @ @ @ @ @ @ @ the Institute of Ecology and Botany in Hungary .
He says that our playing with dogs is a key component of the human-canine bond .
But breeds vary in their degree of playfulness .
For example , a breed called the Vizsla is very playful .
“ On the other hand , the Chihuahua doesn ’ t like to play at all .
Of course , you can train a little bit , but the average level of playfulness will be always lower than in the Hungarian Vizsla.
” Garamszegi and his colleagues @ @ @ @ @ @ @ purebred dogs across 132 breeds , from Pomeranians to Great Danes .
The dogs were all given a test measuring their degree of enthusiasm for a game of tug-of-war with people .
“ We were interested in whether breeds could be distinguished by their average level of playfulness , and what are the evolutionary forces that makes different breeds behave differently.
” The researchers found that after controlling for the degree of genetic relatedness between breeds , dogs bred for herding and sporting were more playful on average than dogs that had been @ @ @ @ @ @ @ non-sporting and toy breeds .
“ For some functions , like hunting or herding , you need trainable dogs and the very strong owner-dog relationship .
So , if you have a playful dog , it 's easy to train .
One way to train a dog is to play with the dog.
” By tracing playfulness back genetically through canine evolution , the researchers showed that the ancestors of today ’ s dogs already possessed an intermediate level of playfulness .
“ So , this was one of the traits that was @ @ @ @ @ @ @ ” “ But some breeds , like the toy dogs , they actually lost some of this playfulness.
” Toy breeds were originally meant to be fashion accessories for the aristocracy , so playfulness could be a liability .
“ They need to match with your clothes , they need to match with your traveling habits .
But they do not need too much attention .
And in this particular situation , if you have a playful dog , it just creates a problem for you.
” The study is in the journal @ @ @ @ @ @ @ et al.
, The link between selection for function and human-directed play behaviour in dogs ] The research could help people choose the optimal pet for their family .
But , ultimately : “ If you want to train your dog , you have to play a lot with your dog .
”

Full Transcript
All domestic dogs belong to a single species that descended from wolves—despite vast differences in size, appearance, behavior and temperament among breeds. While dogs first became domesticated tens of thousands of years ago, the breeds we know today are largely the result of selection for certain traits by humans over the past several hundred years.
“We have an enormous amount of diversity within the same species, and we can rarely observe such diversity in nature. So it’s a wonderful system to understand how evolution works within a short period of time.”
Evolutionary biologist László Garamszegi of the Institute of Ecology and Botany in Hungary. He says that our playing with dogs is a key component of the human-canine bond. But breeds vary in their degree of playfulness. For example, a breed called the Vizsla is very playful.
“On the other hand, the Chihuahua doesn’t like to play at all. Of course, you can train a little bit, but the average level of playfulness will be always lower than in the Hungarian Vizsla.”
Garamszegi and his colleagues analyzed the playfulness of more than 89,000 purebred dogs across 132 breeds, from Pomeranians to Great Danes. The dogs were all given a test measuring their degree of enthusiasm for a game of tug-of-war with people.
“We were interested in whether breeds could be distinguished by their average level of playfulness and what are the evolutionary forces that makes different breeds behave differently.”
The researchers found that after controlling for the degree of genetic relatedness between breeds, dogs bred for herding and sporting were more playful on average than dogs that had been selected for other purposes like the nonsporting and toy breeds.
“For some functions, like hunting or herding, you need trainable dogs and the very strong owner-dog relationship. So if you have a playful dog, it’s easy to train. One way to train a dog is to play with the dog.”
By tracing playfulness back genetically through canine evolution, the researchers showed that the ancestors of today’s dogs already possessed an intermediate level of playfulness.
“So this was one of the traits that was also important during the process of domestication.”
Selective breeding often amplified the trait.
“But some breeds, like the toy dogs, they actually lost some of this playfulness.”
Toy breeds were originally meant to be fashion accessories for the aristocracy, so playfulness could be a liability.
“They need to match with your clothes; they need to match with your traveling habits. But they do not need too much attention. And in this particular situation, if you have a playful dog, it just creates a problem for you.”
The study is in the journal Biology Letters. [Niclas Kolm et al., The link between selection for function and human-directed play behaviour in dogs]
The research could help people choose the optimal pet for their family. But ultimately ...
“If you want to train your dog, you have to play a lot with your dog.”
—Susanne Bard
[The above text is a transcript of this podcast.]


scientificamerican--2020-10-13--Natural Disasters May Push Global Finances to the Brink

Over the past two decades , 20 natural disasters made worse by climate change have caused damage to countries worth 10 % or more of their national output .
In the most severe instance , the devastation Hurricane Maria brought to the tiny Caribbean country of Dominica in 2017 accounted for 260 % of its gross domestic product .
Two years earlier , Tropical Storm Erika caused damage worth 90 % of Dominica 's GDP .
The eye-popping figures illustrate just one of the threats a hotter , stormier world poses to sovereign debt and the global financial system that @ @ @ @ @ @ @ sprawling new report from a group of academics , environmentalists and financial analysts .
The financial stability of fossil-fuel-producing nations is also at risk , the 145-page report found , due to international climate policies and the accelerating transition to cleaner energy .
Released yesterday by a team of researchers from the University of London 's Centre for Sustainable Finance , the World Wide Fund for Nature 's Singapore office , the Asian Development Bank Institute and the climate risk data company Four Twenty Seven Inc. , the report urged governments and international @ @ @ @ @ @ @ action to reduce the risks to sovereign debt .
`` Sovereign risk matters , '' said the researchers , who described sovereign debt as `` the single most important asset class . ''
At the end of last year , there was around $ 70 trillion of outstanding government debt or 28 % of total global debt , the researchers found .
That sovereign debt also `` serves as a benchmark for the pricing of corporate debt , '' they said .
Climate change is already straining the finances of small countries like @ @ @ @ @ @ @ climate change .
For instance , the report noted that a series of hurricanes in the early 2000s forced both Grenada and the Dominican Republic to restructure their sovereign debts , a process that alleviated their short-term financial burdens but made it more expensive for them to borrow in the future .
While no countries have seen their borrowing costs increase yet solely due to climate risks , the major ratings agencies are increasingly taking the threat of natural disasters into account .
As the planet warms , more countries will face similar @ @ @ @ @ @ @ Myanmar , the Philippines and other nearby nations .
`` The implications of climate change for macrofinancial stability and sovereign risk are likely to be material for most if not all countries in Southeast Asia , '' the report said .
The finances of other countries that are heavily dependent on fossil fuel exports also are likely to come under growing pressure as demand for oil , natural gas and coal diminishes , the report found .
Particularly at risk from the ongoing energy transition are Russia , which gets a third of @ @ @ @ @ @ @ Saudi Arabia , where the government 's entire revenues stem from drilling for oil and gas .
Countries can reduce the threat climate change poses to their debts by assessing expected impacts , disclosing that information to the market , and creating incentives to direct public and private investment into curbing climate change and preparing for its physical impacts , the researchers said .
International development organizations can help fund those efforts in developing countries , which are the most at risk but least able to prepare for climate impacts .
If governments @ @ @ @ @ @ @ the growing sovereign debt threat , it could lead to a `` vicious circle '' for some countries , the researchers said .
Recurring storms , heat waves and floods have the potential to crush the borrowing ability of vulnerable nations , leaving them even more exposed to future disasters .
`` Governments need to take urgent action to climate-proof their economies and public finances , '' the report said .
`` If they do n't succeed in this , they will be left helpless in an ever-worsening spiral of climate vulnerability and @ @ @ @ @ @ @ Climatewire with permission from E & E News .
E & E provides daily coverage of essential energy and environmental news at www.eenews.net .

Over the past two decades, 20 natural disasters made worse by climate change have caused damage to countries worth 10% or more of their national output.
In the most severe instance, the devastation Hurricane Maria brought to the tiny Caribbean country of Dominica in 2017 accounted for 260% of its gross domestic product. Two years earlier, Tropical Storm Erika caused damage worth 90% of Dominica's GDP.
The eye-popping figures illustrate just one of the threats a hotter, stormier world poses to sovereign debt and the global financial system that relies on it, according to a sprawling new report from a group of academics, environmentalists and financial analysts. The financial stability of fossil-fuel-producing nations is also at risk, the 145-page report found, due to international climate policies and the accelerating transition to cleaner energy.
Released yesterday by a team of researchers from the University of London's Centre for Sustainable Finance, the World Wide Fund for Nature's Singapore office, the Asian Development Bank Institute and the climate risk data company Four Twenty Seven Inc., the report urged governments and international development banks to take swift and coordinated action to reduce the risks to sovereign debt.
"Sovereign risk matters," said the researchers, who described sovereign debt as "the single most important asset class."
At the end of last year, there was around $70 trillion of outstanding government debt or 28% of total global debt, the researchers found. That sovereign debt also "serves as a benchmark for the pricing of corporate debt," they said.
Climate change is already straining the finances of small countries like Dominica that are physically at risk from climate change. For instance, the report noted that a series of hurricanes in the early 2000s forced both Grenada and the Dominican Republic to restructure their sovereign debts, a process that alleviated their short-term financial burdens but made it more expensive for them to borrow in the future.
While no countries have seen their borrowing costs increase yet solely due to climate risks, the major ratings agencies are increasingly taking the threat of natural disasters into account.
As the planet warms, more countries will face similar physical and financial threats, particularly in Myanmar, the Philippines and other nearby nations.
"The implications of climate change for macrofinancial stability and sovereign risk are likely to be material for most if not all countries in Southeast Asia," the report said.
The finances of other countries that are heavily dependent on fossil fuel exports also are likely to come under growing pressure as demand for oil, natural gas and coal diminishes, the report found. Particularly at risk from the ongoing energy transition are Russia, which gets a third of government revenues from fossil fuels, and Saudi Arabia, where the government's entire revenues stem from drilling for oil and gas.
Countries can reduce the threat climate change poses to their debts by assessing expected impacts, disclosing that information to the market, and creating incentives to direct public and private investment into curbing climate change and preparing for its physical impacts, the researchers said. International development organizations can help fund those efforts in developing countries, which are the most at risk but least able to prepare for climate impacts.
If governments and international institutions fail to quickly counter the growing sovereign debt threat, it could lead to a "vicious circle" for some countries, the researchers said. Recurring storms, heat waves and floods have the potential to crush the borrowing ability of vulnerable nations, leaving them even more exposed to future disasters.
"Governments need to take urgent action to climate-proof their economies and public finances," the report said. "If they don't succeed in this, they will be left helpless in an ever-worsening spiral of climate vulnerability and unsustainable debt burdens."
Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.


scientificamerican--2020-10-11--Neandertal DNA May Be COVID Risk

Neandertal DNA May Be COVID Risk

The risk factors for COVID-19 are many : old age , obesity , heart conditions .
But early genetic studies have identified another trait that some people who develop severe COVID-19 seem to share : a cluster of genetic variations on their third chromosome .
And that DNA sequence likely derives from Neandertals , says Hugo Zeberg of the Max Planck Institute .
“ It ’ s quite striking this variant has lingered on for 50,000 years.
” Fifty thousand years ago is the approximate time humans and Neandertals interbred .
And over the millennia , these Neandertal variants have @ @ @ @ @ @ @ populations than others .
For example , 16 percent of people of European descent carry at least one copy of the Neandertal stretch .
Half of South Asians do—and nearly two thirds of Bangladeshis .
“ And it ’ s fascinating it is so high—points to the fact that it must have been beneficial in the past .
It ’ s much higher than we expect .
And then it ’ s totally expunged in East Asia and China .
So something has happened , driving the frequency up in certain places and @ @ @ @ @ @ @ The details are in the journal Nature .
[ Hugo Zeberg and Svante Pääbo , The major genetic risk factor for severe COVID- 19 is inherited from Neanderthals ] Zeberg and his colleague write that perhaps the Neandertal DNA happens to boost the risk of developing severe COVID-19—and they point to the fact that in the U.K. , people of Bangladeshi descent have twice the risk of dying of COVID-19 than the general population .
But as epidemiologist Keith Neal of the University of Nottingham pointed out via e-mail , people of African @ @ @ @ @ @ @ hurt more by the virus—despite having hardly any Neandertal genes .
Instead it ’ s social factors—like crowded , multigenerational households or working frontline jobs—that are more likely to be driving the trends seen in the U.K. That ’ s according to Andrew Hayward , director of the Institute of Epidemiology and Health Care at University College London .
And as both epidemiologists pointed out , it ’ s worth remembering that you can only develop severe COVID-19 if you ’ re exposed to the virus in the first place .
[ The @ @ @ @ @ @ @ podcast . ]

Full Transcript
The risk factors for COVID-19 are many: old age, obesity, heart conditions. But early genetic studies have identified another trait that some people who develop severe COVID-19 seem to share: a cluster of genetic variations on their third chromosome.
And that DNA sequence likely derives from Neandertals, says Hugo Zeberg of the Max Planck Institute.
“It’s quite striking this variant has lingered on for 50,000 years.”
Fifty thousand years ago is the approximate time humans and Neandertals interbred. And over the millennia, these Neandertal variants have become more common in some Homo sapiens populations than others.
For example, 16 percent of people of European descent carry at least one copy of the Neandertal stretch. Half of South Asians do—and nearly two thirds of Bangladeshis.
“And it’s fascinating it is so high—points to the fact that it must have been beneficial in the past. It’s much higher than we expect. And then it’s totally expunged in East Asia and China. So something has happened, driving the frequency up in certain places and removing it totally in other places.”
The details are in the journal Nature. [Hugo Zeberg and Svante Pääbo, The major genetic risk factor for severe COVID- 19 is inherited from Neanderthals]
Zeberg and his colleague write that perhaps the Neandertal DNA happens to boost the risk of developing severe COVID-19—and they point to the fact that in the U.K., people of Bangladeshi descent have twice the risk of dying of COVID-19 than the general population.
But as epidemiologist Keith Neal of the University of Nottingham pointed out via e-mail, people of African descent in the U.K. are also being hurt more by the virus—despite having hardly any Neandertal genes.
Instead it’s social factors—like crowded, multigenerational households or working frontline jobs—that are more likely to be driving the trends seen in the U.K. That’s according to Andrew Hayward, director of the Institute of Epidemiology and Health Care at University College London.
And as both epidemiologists pointed out, it’s worth remembering that you can only develop severe COVID-19 if you’re exposed to the virus in the first place.
—Christopher Intagliata
[The above text is a transcript of this podcast.]


scientificamerican--2020-10-14--How to Avoid COVID While Voting

How to Avoid COVID While Voting

Zeke Dunn of Brooklyn has worked at polling places in nearly every primary and general election since 2017 .
The 39-year-old television producer says doing so provides a way for him to connect with his neighbors and fulfill his civic duty .
But this past June he skipped working in New York State ’ s primary : his partner is pregnant , and he could not risk bringing the novel coronavirus home from a polling place .
As infection rates in New York City declined to low levels over the summer , Dunn decided to work the polls this November @ @ @ @ @ @ @ .
“ I ’ m not crazy about the risks , ” he says .
“ If it ’ s the same as it normally is , it ’ s exactly what they tell you not to do ” to avoid COVID-19 : spending 12- to 14-hour shifts in close proximity to other poll workers , as well as interacting with hundreds of voters , in an old and poorly ventilated building .
Dunn says he is determined to show up despite the risks—and this was not a decision he came to lightly @ @ @ @ @ @ @ older people work these jobs , ” he says .
“ If my being willing to work in a high-contact role means they can be put in a job that has less contact with other people because I came to work that day , I ’ d be happy to make that concession.
” He plans on bringing a face shield and several KN95 masks , which block 95 percent of particles smaller than 0.3 micron , on Election Day .
In June the U.S. Centers for Disease Control and Prevention issued guidelines @ @ @ @ @ @ @ at polling places .
The recommendations advise poll workers and voters to adopt many of the same measures public health experts have encouraged in other settings : wearing masks , maintaining social distancing , and disinfecting surfaces and voting equipment .
And people who feel unwell or have recently been exposed to someone with the virus should stay home .
“ It ’ s incumbent upon all election officials at every level to advocate for the recommendations by the CDC for social distancing and mask wearing , ” says C. Perry Brown , @ @ @ @ @ @ @ University ’ s Institute of Public Health .
“ The only way to cut down on transmission is to adhere to the recommendations.
” Brown says he thinks officials should even go so far as to mandate wearing a mask in public .
( Some states already have such mandates , but others do not . )
Brown recommends that voters look for a voting booth that is next to an empty one and bring disinfecting wipes to quickly clean the booth before touching anything in it .
Voters should also pay attention @ @ @ @ @ @ @ proper infection control protocols—and speak up if it is not—says Lenora Campbell , dean of the College of Health and Human Sciences at North Carolina Agricultural and Technical State University .
She says poll workers should have a plan for how to deal with any voters who might refuse to wear a mask .
“ It is everyone ’ s responsibility to ensure a safe voting experience , ” Campbell says .
Michael Kohanski , a rhinology fellow at the University of Pennsylvania ’ s Perelman School of Medicine , recommends that voters @ @ @ @ @ @ @ are less likely to be crowded and take advantage of early voting options if available .
“ Also , plan a backup time to vote in case you are not comfortable with the wait time at a polling location , ” he says .
“ Take the time to know all the up- and down-ballot candidates and any referendum items that are on your ballot , so you can reduce your indoor time while voting.
” The polling places themselves need to be prepared , too .
In July Lidia Morawska , an @ @ @ @ @ @ @ for Air Quality and Health at Queensland University of Technology in Australia , co-authored an open letter in Clinical Infectious Diseases urging public health agencies such as the World Health Organization to recognize the possibility of airborne transmission of coronavirus .
That week the WHO updated its guidelines to acknowledge the risk of such transmission .
The CDC made a similar update on October 5 .
Morawska says election officials should maximize airflow at polling places by opening windows or running ventilation systems on high and without recirculation in order to bring in @ @ @ @ @ @ @ of airborne spread .
“ Local building ventilation engineers should be consulted to identify the best measures , ” Morawska says .
“ If it is not possible to provide adequate ventilation , air purifiers may be installed—and everybody should be wearing masks , particularly the [ polling ] staff , as they may be potentially exposed in these environments for a long time.
” President Donald Trump—who trails his opponent , former vice president Joe Biden , in national polls—has frequently distorted the facts about mail-in voting and has made unfounded claims @ @ @ @ @ @ @ are safe and secure , but Trump ’ s falsehoods may persuade some Americans to vote in person instead .
Ben Hovland , chairman of the U.S. Election Assistance Commission , says it is important for voters to know they have options .
“ [ Voters should ] think about how they ’ re going to engage and know what their options are , ” he says .
“ Every state has an option to vote by mail or absentee ballot , ” although a handful of states still require an excuse , @ @ @ @ @ @ @ who either want or need to vote in person should go during off hours or take advantage of early voting wherever it is available .
“ Election Day is the last day to vote , ” Hovland says .
“ As we spread out the number of Americans participating over a broader election period , rather than just on Election Day , that helps reduce congestion and helps make a safer voting experience for all Americans.
” Read more about the coronavirus outbreak from Scientific American here .
And read coverage from our @ @ @ @ @ @

Zeke Dunn of Brooklyn has worked at polling places in nearly every primary and general election since 2017. The 39-year-old television producer says doing so provides a way for him to connect with his neighbors and fulfill his civic duty. But this past June he skipped working in New York State’s primary: his partner is pregnant, and he could not risk bringing the novel coronavirus home from a polling place. As infection rates in New York City declined to low levels over the summer, Dunn decided to work the polls this November. But he worries about getting COVID-19.
“I’m not crazy about the risks,” he says. “If it’s the same as it normally is, it’s exactly what they tell you not to do” to avoid COVID-19: spending 12- to 14-hour shifts in close proximity to other poll workers, as well as interacting with hundreds of voters, in an old and poorly ventilated building.
Dunn says he is determined to show up despite the risks—and this was not a decision he came to lightly. “I thought about how many older people work these jobs,” he says. “If my being willing to work in a high-contact role means they can be put in a job that has less contact with other people because I came to work that day, I’d be happy to make that concession.” He plans on bringing a face shield and several KN95 masks, which block 95 percent of particles larger than 0.3 micron, on Election Day.*
In June the U.S. Centers for Disease Control and Prevention issued guidelines to help prevent the spread of COVID-19 at polling places. The recommendations advise poll workers and voters to adopt many of the same measures public health experts have encouraged in other settings: wearing masks, maintaining social distancing, and disinfecting surfaces and voting equipment. And people who feel unwell or have recently been exposed to someone with the virus should stay home.
“It’s incumbent upon all election officials at every level to advocate for the recommendations by the CDC for social distancing and mask wearing,” says C. Perry Brown, an epidemiologist at Florida A&M University’s Institute of Public Health. “The only way to cut down on transmission is to adhere to the recommendations.” Brown says he thinks officials should even go so far as to mandate wearing a mask in public. (Some states already have such mandates, but others do not.) Brown recommends that voters look for a voting booth that is next to an empty one and bring disinfecting wipes to quickly clean the booth before touching anything in it.
Voters should also pay attention to whether their polling place is following proper infection control protocols—and speak up if it is not—says Lenora Campbell, dean of the College of Health and Human Sciences at North Carolina Agricultural and Technical State University. She says poll workers should have a plan for how to deal with any voters who might refuse to wear a mask. “It is everyone’s responsibility to ensure a safe voting experience,” Campbell says.
Michael Kohanski, a rhinologist at the University of Pennsylvania’s Perelman School of Medicine, recommends that voters go to the polls at times that are less likely to be crowded and take advantage of early voting options if available. “Also, plan a backup time to vote in case you are not comfortable with the wait time at a polling location,” he says. “Take the time to know all the up- and down-ballot candidates and any referendum items that are on your ballot, so you can reduce your indoor time while voting.”
The polling places themselves need to be prepared, too. In July Lidia Morawska, an aerosol scientist who directs the International Laboratory for Air Quality and Health at Queensland University of Technology in Australia, co-authored an open letter in Clinical Infectious Diseases urging public health agencies such as the World Health Organization to recognize the possibility of airborne transmission of coronavirus. That week the WHO updated its guidelines to acknowledge the risk of such transmission. The CDC made a similar update on October 5. Morawska says election officials should maximize airflow at polling places by opening windows or running ventilation systems on high and without recirculation in order to bring in fresh outside air and reduce the risk of airborne spread.
“Local building ventilation engineers should be consulted to identify the best measures,” Morawska says. “If it is not possible to provide adequate ventilation, air purifiers may be installed—and everybody should be wearing masks, particularly the [polling] staff, as they may be potentially exposed in these environments for a long time.”
President Donald Trump—who trails his opponent, former vice president Joe Biden, in national polls—has frequently distorted the facts about mail-in voting and has made unfounded claims about potential ballot fraud. Mail-in ballots are safe and secure, but Trump’s falsehoods may persuade some Americans to vote in person instead. Ben Hovland, chairman of the U.S. Election Assistance Commission, says it is important for voters to know they have options. “[Voters should] think about how they’re going to engage and know what their options are,” he says. “Every state has an option to vote by mail or absentee ballot,” although a handful of states still require an excuse, such as age or disability. People who either want or need to vote in person should go during off hours or take advantage of early voting wherever it is available.
“Election Day is the last day to vote,” Hovland says. “As we spread out the number of Americans participating over a broader election period, rather than just on Election Day, that helps reduce congestion and helps make a safer voting experience for all Americans.”
Read more about the coronavirus outbreak from Scientific American here. And read coverage from our international network of magazines here.
*Editor’s Note (10/14/20): This sentence has been edited after posting to correct the description of KN95 masks.


scientificamerican--2020-10-14--Galileo and the Science Deniers

Galileo and the Science Deniers

Four hundred years ago Galileo Galilei ’ s scientific findings were rejected because they didn ’ t fit the prevailing @ @ @ @ @ His story is disturbingly relevant today .
Astrophysicist and author Mario Livio and Scientific American @ @ @ @ @ lessons from Galileo ’ s life for dealing with science deniers now , plus a @ @ @ @ @ ’ s famous motto , “ And yet it moves .
”

Four hundred years ago Galileo Galilei’s scientific findings were rejected because they didn’t fit the prevailing beliefs of the time. His story is disturbingly relevant today. Astrophysicist and author Mario Livio and Scientific American editor Clara Moskowitz to discusses lessons from Galileo’s life for dealing with science deniers now, plus a historical detective story about Galileo’s famous motto, “And yet it moves.”