Life on Mars: Imagining Martians

If you had the chance to travel to Mars, would you take it?

Astronomer David A. Weintraub thinks it won’t be long before we are faced with this question not as a hypothetical, but as a real option. Based on the pace of research and the growing private interest in space exploration, humans might be considering trips to Mars before the next century.

In his new book Life on Mars: What to Know Before We Go, Weintraub argues that would-be colonizers of the red planet should first learn whether life already exists on Mars. Just as colonization of various parts of Earth has historically decimated human, animal, and plant populations, so, argues Weintraub, will human colonization of Mars dramatically affect and likely destroy any life that might already exist on Mars. Before we visit, we need to know what – and whom – we might be visiting.

While scientists have yet to determine whether life exists on the red planet, they agree that if Martians do exist, they probably aren’t little green men. So where does our popular idea of Martians come from? Artists and writers have been imagining and depicting Martian life in a variety of ways since long before space travel was a reality. Check out these descriptions of imagined Martian life from over one hundred years ago.

Cover of The Martian, by George du Maurier

In George du Maurier’s 1897 gothic science fiction story The Martian, Martians are described as furry amphibians who are highly skilled in metalworking and sculpting:

“Man in Mars is, it appears, a very different being from what he is here. He is amphibious, and descends from no monkey, but from a small animal that seems to be something between our seal and our sea-lion….

“His five senses are extraordinarily acute, even the sense of touch in his webbed fingers and toes….

“These exemplary Martians wear no clothes but the exquisite fur with which nature has endowed them, and which constitutes a part of their immense beauty….

“They feed exclusively on edible moss and roots and submarine seaweed, which they know how to grow and prepare and preserve. Except for heavy-winged bat-like birds, and big fish, which they have domesticated and use for their own purposes in an incredible manner (incarnating a portion of themselves and their consciousness at will in their bodies), they have cleared Mars of all useless and harmful and mutually destructive forms of animal life. A sorry fauna, the Martian—even at its best—and a flora beneath contempt, compared to ours.”

“How the Earth Men Learned the Martian Language,” from Edison’s Conquest of Mars by Garrett P. Serviss

In Garrett Serviss’s Edison’s Conquest of Mars (1898), on the other hand, Martians are huge creatures, two to three times as tall as a human:

“It is impossible for me to describe the appearance of this creature in terms that would be readily understood. Was he like a man? Yes and no. He possessed many human characteristics, but they were exaggerated and monstrous in scale and in detail. His head was of enormous size, and his huge projecting eyes gleamed with a strange fire of intelligence. His face was like a caricature, but not one to make the beholder laugh. Drawing himself up, he towered to a height of at least fifteen feet.”

Edwin Lester Arnold, in Lieut. Gullivar Jones: His Vacation, published in 1905, describes Martians instead as “graceful and slow,” with an “odor of friendly, slothful happiness about them”:

“They were the prettiest, daintiest folk ever eyes looked upon, well-formed and like to us as could be in the main, but slender and willowy, so dainty and light, both the men and the women, so pretty of cheek and hair, so mild of aspect, I felt, as I strode amongst them, I could have plucked them like flowers and bound them up in bunches with my belt. And yet somehow I liked them from the first minute; such a happy, careless, light-hearted race, again I say, never was seen before.” 

“The old man sat and talked with me for hours,” from A Princess of Mars by Edgar Rice Burroughs

And in Edgar Rice Burroughs’ A Princess of Mars, published in 1917, Martians are finally depicted as the little green men of the popular imagination:

“Five or six had already hatched and the grotesque caricatures which sat blinking in the sunlight were enough to cause me to doubt my sanity. They seemed mostly head, with little scrawny bodies, long necks and six legs, or, as I afterward learned, two legs and two arms, with an intermediary pair of limbs which could be used at will either as arms or legs. Their eyes were set at the extreme sides of their heads a trifle above the center and protruded in such a manner that they could be directed either forward or back and also independently of each other, thus permitting this queer animal to look in any direction, or in two directions at once, without the necessity of turning the head.

“The ears, which were slightly above the eyes and closer together, were small, cup-shaped antennae, protruding not more than an inch on these young specimens. Their noses were but longitudinal slits in the center of their faces, midway between their mouths and ears.

“There was no hair on their bodies, which were of a very light yellowish-green color. In the adults, as I was to learn quite soon, this color deepens to an olive green and is darker in the male than in the female. Further, the heads of the adults are not so out of proportion to their bodies as in the case of the young.”

To learn more about Martians in popular culture, the history of planetary astronomy, and the scientific search for life on Mars, read David Weintraub’s Life on Mars!

David Weintraub on Life on Mars: What to Know Before We Go

WeintraubDoes life exist on Mars? The question has captivated humans for centuries, but today it has taken on new urgency. NASA plans to send astronauts to Mars orbit by the 2030s. SpaceX wants to go by 2024, while Mars One wants to land a permanent settlement there in 2032. As we gear up for missions like these, we have a responsibility to think deeply about what kinds of life may already inhabit the plane—and whether we have the right to invite ourselves in. This book tells the complete story of the quest to answer one of the most tantalizing questions in astronomy. But it is more than a history. Life on Mars explains what we need to know before we go.

Why does Mars matter?

Are we alone in the universe? Earth might be an oasis of life, the only place in the universe where living beings of any kind exist. On the other hand, life might be as common across the universe as the hundreds of billions of stars and planets that populate it. Mars is the closest habitable world in the universe where we can begin to learn about extraterrestrial life. If life is common, if the genesis of life is possible given the right environment and the necessary elemental materials, some form of life might exist right next door, on Mars, and if life were discovered on Mars that is of an independent origin than life on Earth, we could safely predict that life is common throughout the universe. Such a discovery would be extraordinary. Mars Matters.

Haven’t we already discovered life on Mars?

Maybe. Maybe not. Some astronomers believe that evidence from NASA’s Viking Lander biology experiments strongly suggest the presence of past or present life on Mars. Other astronomers believe that evidence found in a meteorite from Mars is evidence of ancient life on Mars. Still others believe that methane gas discovered in the atmosphere of Mars is evidence for life on Mars today. However, no consensus exists. None of the data is definitive that would prove or disprove the hypothesis that Mars once harbored or still nurtures life. The jury is still out.

Could life on Mars and life on Earth be related?

Could be. In order for a meteorite to get knocked off Mars and arrive on Earth, several things must happen. First, an asteroid of significant size must hit the surface of Mars and some of the debris from that impact must be lofted off the surface intact and at high speed. The impact debris kicked off the surface then must drill a hole through the Martian atmosphere and emerge above the atmosphere with a high enough velocity (known as “escape velocity”) to escape the gravitational clutches of Mars. Then that object has to end up on an orbit that intersects with that of Earth. All of these things are improbable but possible. Have they actually happened?

A meteoritic breakthrough occurred in 1982, when the leader of the 1981–1982 U.S. search party looking for meteorites in Antarctica found a tiny, unusual-looking rock now known as ALH 81005, which showed mineralogical similarities to lunar rocks. By 1983, several teams of meteoriticists, working independently, had confirmed that this specimen was, without any doubt, a lunar meteorite. For the first time, we had evidence that meteorites can come from objects as large as our Moon.

Then, in 1985, a geochemist proved that the gases trapped inside air bubbles inside EETA 79001, another Antarctic meteorite, this one collected in 1979 in the Elephant Moraine region, were a perfect match to the gases found by NASA’s Viking lander in the atmosphere of Mars. Therefore, without any doubt, EETA 79001 itself was a piece of Mars. We now know of several dozen meteorites that are, without question, of Martian origin.

If a meteorite can travel from Mars to Earth (or vica versa), then life could be transported by this vehicle from one planet to the other.

Why should you care about microscopic Martians?

Do microscopic Martians matter? Yes. Microscopic Martians, if they exist, would be astoundingly important to our understanding of life in the universe. A second genesis, life that began completely independently of terrestrial origins, might have occurred on Mars. Even if life on Mars is limited to bacterial-sized beings, buried underground or hiding deep in a crevice where they are protected from dangerous ultraviolet radiation and cosmic rays and where they can find water, those beings would teach us something of enormous importance about the existence of life beyond Earth. Life on Mars that is independent of life on Earth would send us a clear message about exobiology: life could happen anywhere and everywhere that conditions allow. Alternatively, if we find microscopic life that is DNA-based, we also receive an enormously important message about exobiology and clues about our distant, evolutionary past: such a discovery would tell us that life is easily transported across interplanetary space. Once life gets started, it can spread, and thus, whether we are Martians or the Martians are us, we’re all related. Finally, if we discover that Mars is barren and sterile, without even microscopic Martians, we will know that we are more alone in the solar system and perhaps in the galaxy and universe than many of us currently think.

How Earth-like is Mars? And does that matter?

Mars is very nearly a twin of Earth. Like Earth, Mars is a small rocky planet with a solid surface and an atmosphere.  Mars orbits the Sun at a similar distance as Earth, where the amount of solar heating is sufficient, for at least part of every year, to allow the possibility of the existence of liquid water on at least parts of the surfaces of both planets. The length of the day and night of Mars — 24 hours, 39 minutes — is extremely similar to the day/night spin (24 hours) of Earth. The obliquity of Mars (the 25 degree tilt of Mars’ rotation axis with respect to the plane of its orbit around the Sun) is almost the same as the tilt of Earth (23.5 degrees). These tilts generate seasonal changes, and the seasonal changes of Mars are very similar to the seasons we find here on Earth. The polar caps on Mars, which are mostly water ice, closely resemble the ice caps on Earth. The thin Martian atmosphere behaves like the thicker atmosphere of Earth, with clouds, frost that condenses on the surface, and winds that blow across the surface of the planet. And Mars has large reservoirs of water, just like Earth.  Yes, differences exist. The mass of Mars is smaller than the mass of Earth; the density and composition of the Martian atmosphere are different from those of Earth; Earth has a strong magnetic field while Mars does not; Mars’ water is either frozen or buried deep beneath the surface, while most of Earth’s water is either frozen or liquid and is at or near the surface.  But if you’re looking for an Earth-like planet where Earth-like forms of life could thrive, Mars is a great place to look.

Why did you decide to write this book?  Why should someone read your book?

I think, without any doubt, that humanity will colonize Mars in the near future, perhaps within a decade, and most certainly by the end of the twenty first century. When we settle on Mars, we will contaminate Mars. If any life exists there today, we almost certainly will alter or destroy it in the same way that human and animal diseases have devastated the native species on every continent and island on Earth to which human explorers have extended their reach, putting life forms that have been isolated and protected from other life forms in harm’s way. After we place human colonies on Mars, we will lose the opportunity to discover, with certainty, whether Mars ever was or still is inhabited.

We have one chance to make these discoveries, and that is the present time before we colonize Mars. I think the knowledge we might gain about Mars and Martian life before we send colonists to the red planet is so unique and valuable that we humans should, collectively, debate whether the 2020s and 2030s are the right time to send the first wave of settlers to Mars. Perhaps we should wait just a bit longer, and let robotic exploration continue until the debate about life on Mars is settled. With this book, I hope to help trigger that public debate before it is too late.

David A. Weintraub is professor of astronomy at Vanderbilt University. He is the author of How Old Is the Universe? and Is Pluto a Planet?: A Historical Journey through the Solar System. He lives in Nashville.

Russell Bonduriansky & Troy Day on Extended Heredity

ExtendedFor much of the twentieth century it was assumed that genes alone mediate the transmission of biological information across generations and provide the raw material for natural selection. In Extended Heredity, leading evolutionary biologists Russell Bonduriansky and Troy Day challenge this premise. Drawing on the latest research, they demonstrate that what happens during our lifetimes—and even our grandparents’ and great-grandparents’ lifetimes—can influence the features of our descendants. On the basis of these discoveries, Bonduriansky and Day develop an extended concept of heredity that upends ideas about how traits can and cannot be transmitted across generations. Extended Heredity reappraises long-held ideas and opens the door to a new understanding of inheritance and evolution.

Why does heredity need to be extended?

We are at an interesting moment in the history of biology. Classical genetics, molecular biology, and genomics have greatly enriched our understanding of how organisms function, why individuals vary, and how biological variation is transmitted from parents to their offspring. But, along the way, biologists have made many discoveries that can’t be shoehorned into the conventional picture. For example, every first-year biology student learns that “acquired traits” can’t be passed on to descendants, but a great deal of evidence now contradicts this conventional wisdom. Taken together, these discoveries strongly suggest that genes are not the whole story, and that heredity needs to be extended to encompass a variety of non-genetic factors that operate alongside genes.

What does extended heredity have to do with evolution?

Heredity is one of the essential ingredients required for evolution to occur. If some individuals have particular features that enable them to produce more surviving offspring, and if those features are heritable, then those features will be represented in a greater proportion of individuals in the next generation. This simple formula is the essence of Darwin’s theory, and it was developed long before the discovery of genes. But, in the 20th century, evolution came to be defined in purely genetic terms because biologists assumed that only genes could be passed on to descendants. So what happens if there’s more to heredity than genes, and if nongenetic hereditary factors operate by very different rules? As we show, extended heredity broadens our understanding of how evolution works and leads to some surprising conclusions.

Weren’t such ideas—so-called “Lamarckian” or “soft” inheritance—refuted long ago?

The history of heredity—in particular, how heredity came to be defined in exclusively genetic terms—is a fascinating story in its own right. A commonly held view is that, after a lengthy scientific debate involving numerous experiments, the evidence ultimately showed that Mendelian genes (which were later recognized as DNA sequences) are the sole bearers of heredity. The actual history is far messier. In fact, the rejection of nongenetic forms of hereditary was never well-justified by evidence or logic, and current efforts to dismiss nongenetic inheritance as irrelevant to evolution don’t fare much better. On the other hand, some of the arguments made by proponents of an “extended evolutionary synthesis” are problematic as well, and so we search for a firm middle-ground.

What would you say to a skeptic?

Many biologists are wary of such unorthodox ideas, and some simply wonder what the fuss is about. After all, evolutionary biology has been wonderfully successful without extended heredity, so why open this can of worms? But science progresses by constantly updating knowledge and reassessing ideas. Not everyone will agree with our concept of extended heredity, but we hope to at least convince skeptics that non-genetic inheritance is real and should no longer be neglected in evolutionary thinking. There is a wealth of intriguing evidence out there that challenges conventional ideas, and we should confront this evidence and see where it leads us.

Is all this just an academic debate or are there practical implications?

Heredity is extremely relevant to health and many other practical concerns. Although our primary focus is on evolution, we also consider some of the practical implications of extended heredity. For example, we are exposed in our daily lives to many substances, such as the BPA found in certain plastic products, that have been shown to affect embryonic development in other animals. Many people are now aware that maternal smoking or obesity can harm a developing foetus, but few know that paternal lifestyle and health can also affect the foetus by reprograming the genes carried in sperm. There’s a disturbing historical dimension to this as well. It’s hard to believe today, but doctors and scientists used to believe so strongly in the exclusive role of genes in heredity that they denied the possibility that toxins ingested by pregnant women—most notably alcohol—could cause congenital abnormalities. We’ve obviously come a long way since then, but the idea that our children’s health and features could be shaped, not only by the genes that we pass to them, but also by our own lifestyle choices is still not widely appreciated.

Russell Bonduriansky is professor of evolutionary biology at the University of New South Wales in Australia. Troy Day is a professor in the Department of Mathematics and Statistics and the Department of Biology at Queen’s University in Canada. His books include Biocalculus and A Biologist’s Guide to Mathematical Modeling in Ecology and Evolution (Princeton).

Eelco Rohling: A view from the ocean for Earth Day

On April 22, we celebrate Earth Day. Mostly, we use this holiday to demonstrate support for environmental protection.

The oceans cover some 72% of Earth’s surface; this is why we sometimes call the Earth the “Blue Planet.” Yet, in a time when people are talking about “the best deals,” the oceans are getting an extremely shoddy one.

Humanity is stretching the global oceanic ecosystem to its limits. Major impacts come from global overfishing, and from the physical destruction of critical pristine environments such as coral reefs and mangrove coasts. Combined, these reduce species diversity and richness, as well as breeding potential and resilience to disease. Our impacts on coastal systems are also strongly reducing the natural protection against wave- and storm-damage. We’d be wise to be more appreciative of, and careful with, our key food supplies and protection from the elements. After all, with 7 billion of us to feed, and with almost half of these people living within 100 miles from the sea, we have it all to lose.

Yet our deal with the oceans is even worse than that. That’s because the oceans also get to be the end-station for everything transported by water, which includes plastics as well as toxic chemicals. To boot, we have for many decades unceremoniously dumped vast quantities of society’s unwanted waste products directly into the oceans. Although legal frameworks have been introduced to limit dumping directly into the sea, illegal practices are still rife. In addition, indirect dumping via rivers—whether wittingly or unwittingly—remains a major headache.

As a result of our wasteful demeanour, we are leaving a legacy of oceans (and wildlife) that are visibly filling up with long-lived non-biodegradable plastics, which leads to graphic news coverage. In consequence, plastic pollution is now being billed by some as our oceans’ biggest threat today. It’s certainly a very visible one, with up to 240,000 tons of plastic floating in the oceans. And that amount is equal to only 1% or less of the amount of plastic that is available for entering the ocean every year. This illustrates the massive potential for the plastic problem to explode out of control.

Much less visible, but just as devastating, is the pollution of our oceans with highly toxic and long-lived chemicals—especially human-made PCBs and other organic compounds, along with concentrated heavy metals. PCBs are among the very worst threats because they are so long-lived and so toxic.

Some 10% of all 1.3 million tons of PCBs produced have made it into the oceans already (that is, about 130,000 tons). While this is alarming enough by itself, there’s up to 9 times as much waiting to be released and make its way into the oceans. All we can do to stop that from happening, is prevent any stored PCBs from making it into the open environment. So far, this has been done to 17% of the stores, while 83% have yet to be eliminated.

PCBs have become widespread in marine organisms, from coastal and estuarine waters to the greatest depths of the largest ocean: the Pacific. They cause an endless list of severe health problems, deformities, hormonal unbalance, immune-system weakening, cancer, and a decrease in fertility. Like most long-lived pollutants, PCBs accumulate into higher concentrations through the food web. Their accumulated impacts in whales already drive important infant mortality, as females pass lethal amounts of PCBs to unborn or suckling calves.

Nutrient-pollution is another big issue. This may sound like a strange type of pollution. After all, wouldn’t more nutrients just lead to more happy life in the ocean? When nutrients come in reasonable amounts, then the answer is yes. But when the nutrient flux is excessive—we then talk about eutrophication—all manner of problems develop. And the flux of artificial and human and animal waste-derived nutrients is excessive in many estuaries and coastal regions. Together with ocean warming, this has caused a rapid global expansion of regions where decomposition of massive algal blooms strips all oxygen from the waters, resulting in vast “dead zones” with completely collapsed ecosystems.

Finally, there is the sinister, lurking threat of global warming and ocean acidification. The current rate of warming has been successfully documented through scientific study, and is 10 to 100 times faster than ever before in the past 65 million years. Meanwhile, ocean acidification is caused by the oceans absorbing roughly a third of our carbon emissions. By now, the oceans have become about 0.1 pH unit more acidic than they were before the industrial revolution; that is an acidity increase of 25%. Projections for a business-as-usual emissions trajectory show a 0.3 to 0.4 pH unit change by 2100. In humans, a 0.2 pH unit change results in seizures, coma, and death. Fish, and most other vertebrates, are equally sensitive.

If the changes are slow enough, organisms can evolve to adapt. But researchers are very concerned about the extreme rate of acidification. For coral reefs, the combination of warming and acidification is certainly implicated in massive bleaching and die-off events that are going on around the world already. And let’s not forget that coral reefs house one third of all oceanic biodiversity, while oceans cover more than two thirds of the Earth surface.

The Oceans, by Eelco RohlingSo here’s my plea

We really need an Earth Day, but we need an Ocean Day as well—to build awareness about  this critical part of our planet.

At a passing glance, the oceans’ problems remain hidden under a mesmerising veil of waves and reflections. We need to remind ourselves to keep looking beneath the surface, and to keep taking this critical system’s pulse, lest it dies without us knowing about it. Maybe then we will realise how urgently we need to stop using it as a dumping ground and infinite food larder. That we instead should look for sustainable ways forward, not just for life on land, but also for life in the oceans.

Our attitude going forward will make or break society. Chances are very high that a marine mass extinction will drag us, the ultimate overpopulated top consumer, along with it.

Eelco J. Rohling is professor of ocean and climate change in the Research School of Earth Sciences at the Australian National University and at the University of Southampton’s National Oceanography Centre Southampton.

Mark Serreze on Brave New Arctic

In the 1990s, researchers in the Arctic noticed that floating summer sea ice had begun receding. This was accompanied by shifts in ocean circulation and unexpected changes in weather patterns throughout the world. The Arctic’s perennially frozen ground, known as permafrost, was warming, and treeless tundra was being overtaken by shrubs. What was going on? Brave New Arctic is Mark Serreze’s riveting firsthand account of how scientists from around the globe came together to find answers. A gripping scientific adventure story, Brave New Arctic shows how the Arctic’s extraordinary transformation serves as a harbinger of things to come if we fail to meet the challenge posed by a warming Earth.

Why should we care about what is going on in the Arctic?

The Arctic is raising a red flag. The region is warming twice as fast as the globe as a whole. The Arctic Ocean is quickly losing its summer sea ice cover, permafrost is thawing, glaciers are retreating, and the Greenland ice sheet is beginning to melt down. The Arctic is telling us that climate change is not something out there in some vague future. It is telling us that it is here and now, and in a big way. We long suspected that as the climate warms, the Arctic would be leading the way, and this is exactly what has happened.

There are a lot of books out there on the topic of climate change. What makes this one different and worth reading?

I wanted to get across how science is actually done. Scientists are trained to think like detectives, looking for evidence, tracking down clues, and playing on hunches. We work together to build knowledge, and stand on the shoulders of those who came before us. It a noble enterprise, but a very human one as well. We sometimes make mistakes (I’ve made a few doozies in my time) and get off the rails. Too often, science gets twisted up with politics. I tell it like it is, as a climate scientist who was there back when the Arctic was just beginning to stir, and both watched and participated in the story of the changing north.

You’ve hinted about how growing up in Maine got you interested in snow and ice. Can you tell us a little about this?

I grew up in coastal Maine in the 1960s and 1970s when there were some pretty impressive winters. Winter was my favorite season. I was way into daredevil sledding, and spent countless hours building the iciest, slickest track possible and modifying my sled for maximum speed. I developed a reputation for building tremendous snow forts with five or six rooms connected by tunnels. We’d would go crawling through the tunnels at night and light candles in each room. Then there was the simple primal joy of watching a big Nor’easter snowstorm come through and grind commerce to halt. The craziest winter activity I got into with my sister Mary and friend Dave was riding ice floes on the Kennebunk River. I probably should have drowned several times over, but, in retrospect, I learned a lot about the behavior of floating ice. Now, this was all back in an era when most of us were free-range kids—my mom would say, “get out of the house, I don’t want to see you ‘til dinner.” So you made your own fun and it wasn’t always safe. But it prepared me very well for a career studying snow and ice.

It took you quite a few years to be convinced of a human role in climate change. Why so long?

As mentioned, scientists are detectives, and we are always weighing the evidence. For me, it was never a question of if we would eventually see the human imprint of climate change in the Arctic—the basic physics behind greenhouse warming had been understood as far back as the late 19th century. Rather, it was a question of whether the evidence was solid enough to say that the imprint had actually emerged. The challenge we were up against is that natural variability is quite strong in the Arctic, the system is very complex, and most of the climate records we had were rather short. By the late 1990s, it was clear that we were seeing big changes, but at least to me, a lot of it still looked like natural variability. It was around the year 2002 or 2003 that the evidence became so overwhelming that I had to turn. So, I was a fence sitter for a long time on the issue of climate change, but that is how science should work. We are trained to be skeptical.

What happened in the year 2007?  Can you summarize?   

In the early summer of 2007, sea ice extent was below average, but this didn’t really grab anyone’s attention. That quickly changed when ice started disappearing at a pace never seen before. Through July and August, it seemed that the entire Arctic sea ice community was watching the daily satellite images with a growing sense of awe and foreboding. Huge chunks of the ice were getting eaten away. By the middle of September, when it was all over, the old record low for sea ice hadn’t just been beaten, it had been blown away. There was no longer any doubt that a Brave New Arctic was upon us. Arctic climate science was never really the same after that.

We keep hearing about how science tends to be a male-dominated field. But the impression that one gets from your book is that this isn’t really the case in climate research. Can you comment?

I don’t know what the actual numbers look like in climate science versus, say, computer science, but in my experience,  when it comes climate research, nobody really cares about your gender. What’s important is what you know and what you can contribute. What you do see, certainly, is more female graduate students now coming through the system in STEM fields (Science, Technology, Education, Mathematics).

Are you frustrated by the general inaction, at least in the United States, to deal with climate change? 

I’m constantly amazed that we don’t take the issue of climate change more seriously in this country. We are adding greenhouse gases to the air. The climate is warming as a result. The physics are well understood. Just as expected, the Arctic is leading the way. Sure, there are uncertainties regarding just how warm it well get,  how much sea level will rise, and changes in extreme events, but we know plenty about what is happening and where we are headed. The costs of inaction are going to far outweigh the costs of addressing this issue.

Mark C. Serreze is director of the National Snow and Ice Data Center, professor of geography, and a fellow of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder. He is the coauthor of The Arctic Climate System. He lives in Boulder, Colorado.

Keith Oatley on Our Minds, Our Selves: A Brief History of Psychology

OatleyAdvances in psychology have revolutionized our understanding of the human mind. Imaging technology allows researchers to monitor brain activity, letting us see what happens when we perceive, think, and feel. But technology is only part of how ideas about the mind and brain have developed over the past century and a half. In Our Minds, Our Selves, distinguished psychologist and writer Keith Oatley provides an engaging, original, and authoritative history of modern psychology told through the stories of its most important breakthroughs and the men and women who made them.

What prompted you to write this book?

There didn’t seem to be a book about the mind that people could read and say, “Oh, that’s why I see a certain person in this way, but feel myself to be rather different,” or “So that’s what goes on in a conversation.” I wanted to write a book on psychology that throws light on everyday human life, that gives the reader a sense of important turning points in research, and that focuses on the deeper principles of how the mind works, principles that help us think about our selves and others.

We like to think that we’re in direct touch with reality, but you say that’s not quite how it is.

In a way we are in touch with reality, but the mind isn’t a place into which reality can enter through eyes and ears. It’s the other way round: we project what we know from our inner understandings onto what comes in from the senses. Think of reading. If you did not know how to read, what you would see on a page would be black bits and white spaces. But since you can read, you project meanings onto these bits and spaces. With people it’s the same. You can read other people’s minds, project your understandings onto them.

You start with the problem of consciousness. Isn’t that a bit difficult?

Consciousness may seem difficult and people have argued about it for centuries, but the basic idea is straightforward. The brain contains some 86 billion nerve cells, each of which has connections to hundreds or thousands of others. We couldn’t possibly be aware of everything that goes on as these neurons interact with each other. The brain gives us a set of conclusions from these processes. This was the theory that Helmholtz proposed. Not many people know it, but really he was the main founder of our understanding of mind. The conclusions the mind offers are what we become conscious of: “That’s what it’s like out there in the world, laid out in space, with people to meet, objects to use, places to go.” From physics we might get a different depiction, perhaps of protons and electrons and waves, but that wouldn’t be of much help to us, in our ordinary lives. The conclusions the brain offers come into our conscious awareness, from sampling patterns of light and sound, to tell us: “That’s what this person means.” Or looking back to something remembered: “That’s what happened.” Or looking forward, with a plan: “Here’s what I might do.”

You say the book is about the principles of mind. What do you mean?

The deepest principle is that the mind offers us conclusions by being able to make models of the world, and even of our own self. A clock is a model of the rotation of the earth. We use it to get up in the morning, or to go and meet a friend. With some kinds of models, we can do more: we can see what would happen if we make alterations to the model, because models are things we can change. We translate an idea, or an aspiration, into our model of the world. Then we can manipulate the model, change it, to create new states. We call this thinking. Then we translate back again, from the resulting model-states into terms of the world again, to see something in a particular way, or to say this, or to do that.

You said there are other principles, too. What’s another one?

The characteristic of our human species that separates from other animals is our ability to cooperate. From an early age, human children, but not chimpanzees, can recognize when someone is trying to do something, but isn’t quite able to, and can know how to help. A two-year-old child, for instance, can see an adult with her hands full of books who seems to be wanting to put the books into a cupboard, but because her hands are full can’t open the door. The two-year-old will open the cupboard door for this person. And children of this age start to make joint plans, for instance when they play. They don’t just play on their own, they play together. Even a simple game like hide-and-seek requires cooperation. Plans that involve goals and activities shared with others become more important than anything else for us: how to join with another in living together, how to raise a family, how to cooperate with others at our place of work for ends that are useful. This principle widens so that we humans form communities and cultures, in which what goes for the whole group becomes important. So we try to be helpful, we are upset by injustice, we don’t want to tolerate people who are destructive. This is called morality. We strive to make the world a better place, not just for our selves, individually, but for everyone.

Is human intelligence going to be overtaken by artificial intelligence?

The most recent kinds of artificial intelligence are starting to think in ways similar to how we humans think, by forming intuitions from many examples, and projecting meanings from these intuitions onto new inputs. Often, when we humans have encountered a new group of people, or a new situation, we have become antagonistic; we have reacted as if the situation is one of conflict. With newer forms of artificial intelligence, we will need to think hard, to take on what is known from psychology, history, and social science, to fashion not conflict but cooperation with these new forms.

Keith Oatley is a distinguished academic researcher and teacher, as well as a prize-winning novelist. He has written for scientific journals, the New York Times, New Scientist, Psychology Today, and Scientific American Mind. He is the author of many books, including Such Stuff as Dreams and The Passionate Muse, and a coauthor of the leading textbook on emotion. He is professor emeritus of cognitive psychology at the University of Toronto and lives in Toronto.

The Royal Institution: Science Lives Here

by Katie Lewis and Keira Andrews

RIThe Royal Institution is a scientific gem in the heart of London. It was founded in 1799 by leading British scientists of the age with the aim of bringing technology and science to the general public. On nearly any day of the year, a member of the public can take part in live events with the world’s leading thinkers, experiment in a research laboratory, and take part in hands-on masterclasses with specially trained experts. The lecture theatre at the Royal Institution is infamous; some truly remarkable scientific breakthroughs have occurred within its walls as a result of the Friday Evening Discourses where top scientists of the time would show off their research. It was here that Thomas Young established the wave theory of light; John Tyndall discovered the greenhouse effect; Humphry Davy discovered nine chemical elements; and Michael Faraday developed the electric motor and electric generator.

Ri

The Royal Institution has left—and continues to leave—a lasting legacy upon the scientific community. One of the more publically-recognised services is the Christmas Lectures that were started by Michael Faraday in 1825 and continue to this day. In today’s world these lectures come in the form of a televised Christmas broadcast aimed at children with a changing theme each year and guest speakers that range from David Attenborough to Richard Dawkins. Originally, however, the lectures are thought to have come to fruition after adults began bringing their children along to the adult afternoon courses in the early 1800s, and someone had the idea of a yearly lecture to inspire a new generation of scientists. These lectures have continued to run every year since 1825—only being put on hold between 1939 and 1942 when the majority of London children had been sent away as evacuees. The Royal Institution also holds over one hundred other events each year on a wide variety of subjects.

It is at these events that many of our Princeton University Press authors have spoken. On average, five of our authors step the boards of this famous lecture theatre each year, and talk animatedly to an audience that ranges from the curious layperson to the science graduate and above. In this, the Royal Institution has never changed; science is for everyone. In recent years, the Royal Institution, colloquially known as the Ri to mimic an element on the periodic table, has hosted Princeton University Press authors across a wide range of scientific subjects from astronomy and the evolution of the human mind, to first impressions and how to clone a mammoth. Last week, it was the turn of Professor Peter Ungar, Distinguished Professor and director of the Environmental Dynamics Program at the University of Arkansas, and author of the Ungarrecently published Princeton book Evolution’s Bite: A Story of Teeth, Diet, and Human Origins (May 2017).

In his fascinating talk, Ungar illustrated how important teeth are for understanding the story of human evolution. Ungar described how a tooth’s “foodprints”—distinctive patterns of microscopic wear and tear—provide telltale details about what an animal actually ate in the past. These clues, combined with groundbreaking research in paleoclimatology, demonstrate how a changing climate altered the food options available to our ancestors—what Ungar calls the biospheric buffet. When diets change, species change, and Ungar traced how diet and an unpredictable climate determined who among our ancestors was winnowed out and who survived, as well as why we transitioned from the role of forager to farmer. By showing us the scars on ancient teeth, Ungar made the important case for what might or might not be the most natural diet for humans.

Ungar also revealed some fascinating facts about teeth in modern humans. Orthodontic issues such as crooked teeth, overbites, and impacted wisdom teeth did not affect our distant ancestors. The reason our mouths are overcrowded lies in the modern diet: our ancestors would have had to chew hard to break up tough foods. Bone responds to strain by growing, and our tooth size evolved to fit perfectly into a jaw exposed to a hard or tough diet. Our modern diet of pizza and burgers does not provide the same challenge for our jaws, and so they are not put under the strain required to reach optimum jaw size. In some tribes around the world, there are groups of people who still eat a similar diet to our ancestors, and it is no coincidence that these people tend to, on the whole, have beautiful straight teeth.

It is amazing what you can learn from teeth; Ungar explained how toothwear shows us how dinosaur jaws moved, allowing us to build muscle onto the bones of the face, to see what they would have looked like. In this way, teeth play an important role in the reconstruction of prehistoric animals, and also the face shapes of our ancestors. Ungar’s talk was a fascinating addition to the Royal Institute’s line-up this year.

Keeping in tone with the idea behind the Christmas Lectures series, it is fascinating to see the number of young children—usually one in ten—in the audience at these adult-level general lectures. It is a benchmark of the accessibility of the Ri that it is not uncommon to see a nine year old articulating her ideas about ecosystems or an eleven year old asking for more details about CRISPR. The Institution, the lecture hall, and the people that encompass it continue to be a point of inspiration for anybody who chooses to listen.

Martin Rees: Stephen Hawking — An Appreciation

Soon after I enrolled as a graduate student at Cambridge University in 1964, I encountered a fellow student, two years ahead of me in his studies; he was unsteady on his feet and spoke with great difficulty. This was Stephen Hawking. He had recently been diagnosed with a degenerative disease, and it was thought that he might not survive long enough even to finish his PhD. But, amazingly, he lived on to the age of 76. Even mere survival would have been a medical marvel, but of course he didn’t just survive. He become one of the most famous scientists  in the world—acclaimed  as a world-leading researcher in mathematical physics, for his best-selling books about space, time, and the cosmos, and for his astonishing triumph over adversity.

Astronomers are used to large numbers. But few numbers could be as large as the odds I’d have given, back in 1964 when Stephen received his ‘death sentence,’ against witnessing this uniquely inspiring crescendo of achievement sustained for more than 50 years. Few, if any, of Einstein’s successors have done more to deepen our insights into gravity, space, and time.

Stephen went to school in St Albans, near London, and then to Oxford University. He was, by all accounts, a ‘laid back’ undergraduate, but his brilliance nonetheless earned him a first class degree in physics, and an ‘entry ticket’ to a research career in Cambridge. Within a few years of the onset of his disease he was wheelchair-bound, and his speech was an indistinct croak that could only be interpreted by those who knew him. But in other respects fortune had favored him. He married a family friend, Jane Wilde, who provided a supportive home life for him and their three children, Robert, Lucy, and Tim.

The 1960s were an exciting period in astronomy and cosmology: this was the decade when evidence began to emerge for black holes and the big bang. In Cambridge, Stephen  joined a lively research group. It was headed by Dennis Sciama, an enthusiastic and effective mentor who urged him to focus on the new mathematical concepts being developed by Roger Penrose, then at London University, which were initiating a renaissance in the study of Einstein’s theory of general relativity. Stephen mastered Penrose’s techniques and quickly came up with a succession of insights into the nature of black holes (then a very new idea),   along with new arguments that our universe had expanded from a ‘big bang.’ The latter work was done jointly with George Ellis, another of Sciama’s students, with whom Stephen wrote a monograph entitled The Large-Scale Structure of Space-Time. Especially important was the realization that the area of a black hole’s horizon (the ‘one-way membranes’ that shroud the interior of black holes, and from within which nothing can escape) could never decrease. The analogy with entropy (a measure of disorder, that likewise can never decrease) was developed further by the late Israeli theorist Jacob Bekenstein. In the subsequent decades, the observational support for these ideas  has strengthened—most spectacularly with the 2016 announcement of the detection of gravitational waves from colliding black holes.

Stephen was elected to the Royal Society, Britain’s main scientific academy, at the exceptionally early age of 32. He was by then so frail that most of us suspected that he could scale no further heights. But, for Stephen, this was still just the beginning. He worked in the same building as I did. I would often push his wheelchair into his office, and he would ask me to open an abstruse book on quantum theory—the science of atoms, not a subject that had hitherto much interested him. He would sit hunched motionless for hours—he couldn’t even to turn the pages without help. I wondered what was going through his mind, and if his powers were failing. But within a year he came up with his best-ever idea—encapsulated in an equation that he said he wanted on his memorial stone.

The great advances in science generally involve  discovering a link between phenomena that seemed hitherto conceptually unconnected: for instance, Isaac Newton famously realized that the force making an apple fall was the same as the force that held the moon and planets in their orbits. Stephen’s ‘eureka moment’ revealed a profound and unexpected  link between gravity and quantum theory: he predicted that black holes would not be completely black, but would radiate in a characteristic way. Bekenstein’s concept that black holes had ‘entropy’ was more than just an analogy. This radiation is only significant for black holes much less massive than stars—and none of these have been found. However, ‘Hawking radiation’ had very deep implications for mathematical physics—indeed one of the main achievements of string theory has been to corroborate his idea. It is still the focus of theoretical interest—a topic of debate and controversy more than 40 years after his discovery. Indeed the Harvard theorist, Andrew Strominger (with whom Stephen recently collaborated) said that this paper had caused ‘more sleepless nights among theoretical physicists than any paper in history.’ The key issue is whether information that is seemingly lost when objects fall into a black hole is in principle recoverable from the radiation when it evaporates. If it is not, this violates a deeply believed general physical principle. In 2013 he was one of the early winners of the Breakthrough Prize, worth 3 million dollars, which was intended to recognize theoretical work.

Cambridge was Stephen’s base throughout his career, and he became a familiar figure navigating his wheelchair around the city’s streets. By the end of the 1970s, he had advanced to one of the most distinguished posts in the University—the Lucasian Professorship of Mathematics, once held by Newton himself. He held this chair with distinction for 30 years; but reached the retiring age in 2009 and thereafter held a special research professorship. He travelled widely: he was an especially frequent visitor at Caltech, in Pasadena, California; and at Texas A&M University. He continued to seek new links between the very large (the cosmos) and the very small (atoms and quantum theory) and to gain deeper insights into the very beginning of our universe—addressing questions like ‘was our big bang the only one?’ He had a remarkable ability to figure things out in his head. But latterly he worked with students and colleagues who would write a formula on a blackboard; he would stare at it, and say whether he agreed with it, and perhaps what should come next.

In 1987, Stephen contracted pneumonia. He had to undergo a tracheotomy, which removed even the limited powers of speech he then possessed. It had been more than 10 years since he could write, or even  use a keyboard. Without speech, the only way he could communicate was by directing his eye towards  one of the letters of the alphabet on a big board in front of him.

But he was saved by technology. He still had the use of one hand; and a computer, controlled by a single lever, allowed him to spell out sentences. These were then declaimed by a speech synthesizer, with the androidal American accent that has since become his trademark. His lectures were, of course, pre-prepared, but conversation remained a struggle. Each word involved several presses of the lever, so even a sentence took several minutes. He learnt to economize with words. His comments were aphoristic or oracular, but often infused with wit. In his later years, he became too weak to control this machine effectively, even via facial muscles or eye movements, and his communication—to his immense frustration—became even slower.

At the time of his tracheotomy operation, he had a rough draft of a book, which he’d hoped would describe his ideas to a wide readership and earn something for his two eldest children, who were then of college age. On his recovery from pneumonia, he resumed work with the help of an editor. When the US edition of   A Brief History of Time appeared, the printers made some errors (a picture was upside down), and the publishers tried to recall the stock. To their amazement, all copies had already been sold. This was the first inkling that the book was destined for runaway success—four years on bestseller lists around the world.

The feature film The Theory of Everything (where he was superbly impersonated by Eddie Redmayne, in an Oscar-winning performance) portrayed  the human story behind his struggle. It surpassed most biopics in  representing the main characters so well that they themselves were happy with the portrayal (even though it understandably omitted and conflated key episodes in his scientific life). Even before this film, his life and work had featured in movies. In  an excellent TV docudrama made in 2004, he was played by Benedict Cumberbatch (In 2012 Cumberbatch spoke his words in a 4-part documentary The Grand Design made for the Discovery TV  Channel).

Why did he become such a ‘cult figure?’ The concept of an imprisoned mind roaming the cosmos plainly grabbed people’s imagination. If he had achieved equal distinction in (say) genetics rather than cosmology, his triumph of intellect against adversity probably wouldn’t have achieved the same resonance with a worldwide public.

The Theory of Everything conveyed with sensitivity how the need for support (first from a succession of students, but later requiring a team of nurses) strained his marriage to breaking point, especially when augmented by the pressure of his growing celebrity. Jane’s book, on which the film is based chronicles the 25 years during which, with amazing dedication, she underpinned his family life and his career.

This is where the film ends. But it left us only half way through Stephen’s adult life. After the split with Jane, Stephen married, in 1995, Elaine Mason, who had been one of his nurses, and whose former husband had designed Stephen’s speech synthesizer. But this partnership broke up within a decade. He was sustained, then and thereafter, by a team of helpers and personal assistants, as well as his family. His daughter Lucy has written books for children with her father as coauthor. His later theories were described, and beautifully illustrated, in other books such as Our Universe in a Nutshell and The Grand Design. These weren’t  bought by quite as many people as his first book—but probably more readers got to the end of them.

The success of A Brief History of Time catapulted Stephen to international stardom. He  featured in numerous TV programs; his lectures filled the Albert Hall, and similar venues in the US and Japan. He  featured in Star Trek and The Simpsons, and in numerous TV documentaries, as well as advertisements. He lectured at Clinton’s White House; he was back there more recently when President Obama presented him with the US Medal of Freedom, a very rare honor for any foreigner—and of course just one of the many awards he accumulated over his career (including Companion of Honor from the UK). In the summer of 2012, he reached perhaps his largest-ever audience when he had a star role at the opening ceremony of the London Paralympics.

His 60th birthday celebrations, in January 2002 , were a memorable occasion for all of us. Hundreds of leading scientists came from all over the world to honor and celebrate Stephen’s discoveries, and to spend a week discussing the latest theories on space, time, and the cosmos. But the celebrations weren’t just scientific—that wouldn’t have been Stephen’s style. Stephen was surrounded by his children and grandchildren; there was music and singing; there were ‘celebrities’ in attendance. And when the week’s events were all over, he celebrated with a trip in a hot air balloon.

It was amazing enough that Stephen reached the age of 60; few of us then thought that he would survive 16 more years. His 70th birthday was again marked by an international gathering of scientists in Cambridge, and also with some razzmatazz. So was his 75th birthday, though now shared by several million people via a livestream on the internet. He was in these last years plainly weakening. But he was still able to ‘deliver’ entertaining (and sometimes rather moving) lectures via his speech synthesizer and with the aid of skillfully prepared visuals.

Stephen continued, right until his last decade, to coauthor technical papers, and speak at premier international conferences—doubly remarkable in a subject where even healthy researchers tend to peak at an early age. Specially influential were his contributions to ‘cosmic inflation’—a theory that many believe describes the ultra-early phases of our expanding universe. A key issue is to understand the primordial seeds which eventually develop into galaxies. He proposed (as, independently, did the Russian theorist Viatcheslav Mukhanov) that these were quantum fluctuations—somewhat analogous to those involved in ‘Hawking radiation’ from black holes. He hosted an important meeting in 1982 where such ideas were thoroughly discussed. Subsequently, particularly with James Hartle and Thomas Hertog, he made further steps towards linking the two great theories of 20th century physics: the quantum theory of the microworld and Einstein’s theory of gravity and space-time.

He continued  to be an inveterate traveller—despite attempts to curb this as his respiration weakened. This wasn’t just to lecture. For instance, on a visit to Canada he was undeterred by having to go two miles down a mine-shaft to visit an underground laboratory where famous and delicate experiments had been done. And on a later trip, only a last-minute health setback prevented him from going to the Galapagos. All these travels—and indeed his everyday working life—involved an entourage of assistants and nurses. His fame, and the allure of his public appearances, gave him the resources for  nursing care, and protected him against the ‘does he take sugar?’ type of indignity that the disabled often suffer.

Stephen was far from being the archetype unworldly or nerdish scientist—his personality remained amazingly unwarped by his frustrations and handicaps. As well as his extensive travels, he enjoyed  trips to theatre or opera. He had robust common sense, and was ready to express forceful political opinions. However, a downside of his iconic status was that that his comments attracted exaggerated attention even on topics where he had  no special expertise—for instance philosophy, or the dangers from aliens or from intelligent machines. And he was sometimes involved in media events where his ‘script’ was written by the promoters of causes about which he may have been ambivalent.

But there was absolutely no gainsaying his lifelong commitment to campaigns for the disabled, and (just in the last few months) in support of the NHS—to which he acknowledged he owed so much. He was always, at the personal level, sensitive to the misfortunes of others. He recorded  that, when in hospital soon after his illness was first diagnosed, his depression was lifted when he compared his lot with a boy in the next bed who was dying of leukemia. And he was firmly aligned with other political campaigns and causes. When he visited Israel, he insisted on going also to the West Bank. Newspapers in 2006 showed remarkable pictures of him, in his wheelchair, surrounded  by fascinated and curious crowds in Ramallah.

Even more astonishing are the pictures of him ‘floating’ in the NASA aircraft  (the ‘vomit comet’) that allows passengers to experience weightlessness—he was manifestly overjoyed at escaping, albeit briefly, the clutches of the gravitational force he’d studied for decades and which had so cruelly imprisoned his body.

Tragedy struck Stephen Hawking when he was only 22. He was diagnosed with a deadly disease, and his  expectations dropped to zero. He himself said that everything that happened since then was a bonus. And what a triumph his life has been. His name will live in the annals of science; millions have had their cosmic horizons widened by his best-selling books; and even more, around the world, have been inspired by a unique example of achievement against all the odds—a manifestation of amazing will-power and determination.

Martin Rees is Astronomer Royal of Great Britain, a Fellow of Trinity College, Cambridge, a former director of the Cambridge Institute of Astronomy and author, most recently, of the bestselling Just Six Numbers: The Deep Forces That Shape the Universe. His forthcoming book, On the Future, will be available in October 2018.

Introducing Volume 15 of The Collected Papers of Albert Einstein

From fraudulent science to hope for European reunification, the newest volume of The Collected Papers of Albert Einstein conveys the breakneck speed of Einstein’s personal and professional life. Volume 15, covering June 1925 to May 1927, is out now!

THE COLLECTED PAPERS OF ALBERT EINSTEIN
Volume 15: The Berlin Years
Writings & Correspondence, June 1925-May 1927, Documentary Edition

Edited by Diana Kormos Buchwald, József Illy, A. J. Kox, Dennis Lehmkuhl, Ze’ev Rosenkranz & Jennifer Nollar James

Princeton University Press, the Einstein Papers Project at the California Institute of Technology, and the Albert Einstein Archives at the Hebrew University of Jerusalem, are pleased to announce the latest volume in the authoritative COLLECTED PAPERS OF ALBERT EINSTEIN. This volume covers one of the most thrilling two-year periods in twentieth-century physics, as matrix mechanics—developed chiefly by W. Heisenberg, M. Born, and P. Jordan—and wave mechanics—developed by E. Schrödinger—supplanted earlier quantum theory. The almost one hundred writings, a third of which have never before been published, and the more than thirteen hundred letters demonstrate Einstein’s immense productivity at a tumultuous time.

Within this volume, Einstein grasps the conceptual peculiarities involved in the new quantum mechanics; falls victim to scientific fraud while in collaboration with E. Rupp; and continues his participation in the League of Nations’ International Committee on Intellectual Cooperation.

ENGLISH TRANSLATION SUPPLEMENT

Every document in The Collected Papers of Albert Einstein appears in the language in which it was written, and this supplementary paperback volume presents the English translations of select portions of non-English materials in Volume 15. This translation does not include notes or annotation of the documentary volume and is not intended for use without the original language documentary edition which provides the extensive editorial commentary necessary for a full historical and scientific understanding of the documents.

Translated by Jennifer Nollar James, Ann M. Hentschel, and Mary Jane Teague, Andreas Aebi and Klaus Hentschel, consultants

THE COLLECTED PAPERS OF ALBERT EINSTEIN

Diana Kormos Buchwald, General Editor

THE COLLECTED PAPERS OF ALBERT EINSTEIN is one of the most ambitious publishing ventures ever undertaken in the documentation of the history of science.  Selected from among more than 40,000 documents contained in the personal collection of Albert Einstein (1879-1955), and 20,000 Einstein and Einstein-related documents discovered by the editors since the beginning of the Einstein Papers Project, The Collected Papers provides the first complete picture of a massive written legacy that ranges from Einstein’s first work on the special and general theories of relativity and the origins of quantum theory, to expressions of his profound concern with international cooperation and reconciliation, civil liberties, education, Zionism, pacifism, and disarmament.  The series will contain over 14,000 documents as full text and will fill close to thirty volumes.  Sponsored by the Hebrew University of Jerusalem and Princeton University Press, the project is located at and supported by the California Institute of Technology and has made available a monumental collection of primary material. It will continue to do so over the life of the project. The Albert Einstein Archives is located at the Hebrew University of Jerusalem. The open access digital edition of the first 14 volumes of the Collected Papers is available online at einsteinpapers.press.princeton.edu.

ABOUT THE SERIES: Fifteen volumes covering Einstein’s life and work up to his forty-eighth birthday have so far been published. They present more than 500 writings and 7,000 letters written by and to Einstein. Every document in The Collected Papers appears in the language in which it was written, while the introduction, headnotes, footnotes, and other scholarly apparatus are in English.  Upon release of each volume, Princeton University Press also publishes an English translation of previously untranslated non-English documents.

ABOUT THE EDITORS: At the California Institute of Technology, Diana Kormos Buchwald is professor of history; A. J. Kox is senior editor and visiting associate in history; József Illy and Ze’ev Rosenkranz are editors and senior researchers in history; Dennis Lehmkuhl is research assistant professor and scientific editor; and Jennifer Nollar James is assistant editor.

Jason Rosenhouse: Yummy, Delicious Pi!

RosenhouseHere is a classic bar bet for you: take a wine glass, the kind with a really long stem. Ask whoever is near you to guess whether the height of the glass or the circumference at the top is greater. Most people will choose the height. In fact, they will regard it as obvious that the height is greater. But they will be wrong! Unless it is a very oddly-shaped glass, the circumference will be significantly greater. (Of course, you will need a piece of string to convince your mark of that.) It is a remarkably effective optical illusion.

As we all learned in grade school, the circumference of a circle is pi times the diameter, and pi is just a little greater than three. So the circumference at the top will be three times longer than the diameter. Any glass taller than that would be unpleasant to drink from.

Apparently knowing something about pi can make you money. Who said math isn’t practical?

I remember being fascinated by pi as a kid. When my father—a chemical engineer—first told me about it, I asked him if there was also a number called cake. The number pi is typically defined as a sort of geometrical object: it is the ratio of the circumference of a circle to its diameter. We could also say that pi is the area of a circle whose diameter is one. Yet somehow it keeps appearing in the most unexpected of places.

For example, suppose you pick two whole numbers at random, by which I mean the usual numbers like 1, 2, 3, 4, and so on. Sometimes the two numbers will share a common factor, like 4 and 6, which share a common factor of 2. Other times the two numbers will share no common factor (other than 1), like 3 and 7. Pairs like the second are said to be relatively prime. It turns out the probability that a pair of randomly chosen numbers is relatively prime is 6 divided by pi squared. Not a circle in sight, yet there is pi!

Or imagine that you have a very large sheet of notebook paper whose lines are one inch apart. Suppose you take a one-inch needle and drop it from a height onto the paper. The probability that the needle hits a line is 2 divided by pi. Only lines this time. Still no circles. This is called the Buffon needle problem, if you were curious.

One of the first things you learn about pi is that it is an irrational number, which means it is an infinite, non-repeating decimal. My sixth grade math teacher told me it was just crazy that a number should behave like that, and that is why it is called irrational. You can imagine my disappointment when I later learned that it is irrational only in the sense that it cannot be expressed as a ratio of whole numbers. I like my teacher’s explanation better. You can find fractions that are good approximations, like 22/7 or 355/113, but approximations are not the real thing.

The fact that pi is an infinite, non-repeating decimal, and that it cannot be written simply in terms of whole numbers, makes it difficult to write down at all. That is why we just give it a name, pi, and call it a day. We could as easily have called it Harry the number if we wanted to, but perhaps that lacks gravitas.

Pi is one of the special numbers of mathematics. Another is e, which is typically defined in ways that require calculus, and which have nothing to do with circles. This is another of those strange, irrational numbers that seems to keep popping up in unexpected places. Still another is i, which is defined to be the square root of minus 1, a number so bizarre it is commonly said to be imaginary. And we certainly should not forget the two most special numbers of them all, by which I mean 1 and 0.

Perhaps having experienced social ostracism at the hands of more normal numbers, the five special numbers have gotten together to create one of the most remarkable equations in mathematics. It is called Euler’s identity, and says:

e+1=0

It is remarkable that these five special numbers, defined in contexts entirely separate from one another, should play together so well. At the risk of seeming melodramatic, religions have started over less.

So take a moment this March 14 to give some thought to the most delicious number we have: pi. We will not have another perfect square day until May 5, 2025 (a date that will be written 5/5/25). And since e is 2.72 when rounded to two decimal places, we will never have an e day until February is granted 72 days. Or perhaps someday we will dramatically increase the size of the calendar, and then we will have e day on the second day of the twenty-seventh month.

But pi day comes every year. Enjoy it!

Jason Rosenhouse is a professor of mathematics at James Madison University in Harrisonburg, Virginia. He is the author or editor of six books, including The Monty Hall Problem: The Remarkable Story of Math’s Most Contentious Brainteaser, and Among the Creationists: Dispatches From the Anti-Evolutionist Frontline. His book Taking Sudoku Seriously, coauthored with Laura Taalman, received the 2012 Prose award, from the American Association of Publishers, for popular science and mathematics. With Jennifer Beineke, he is the editor of the Mathematics of Various Entertaining Subjects series, published by Princeton University Press and the Museum of Mathematics in New York. He is currently working on a book about logic puzzles, to be published by Princeton.

Jeffrey Bub & Tanya Bub: There are recipes for Pi. But quantum mechanics?

There’s a recipe for Pi, in fact quite a few recipes. Here’s one that dates to the fifteenth century, discovered by the Indian mathematician and astronomer Nilakantha:

Bub

For the trillions of decimal places to which the digits have been calculated, each digit in the decimal expansion of Pi occurs about one-tenth of the time, each pair of digits about one-hundredth of the time, and so on. Its still a deep unsolved mathematical problem to prove that this is in fact a feature of Pi—that the digits will continue to be uniformly distributed in this sense as more and more digits are calculated—but the digits aren’t totally random, since there’s a recipe for calculating them.

Quantum mechanics supplies a recipe for calculating the probabilities of events, how likely it is for an event to happen, but the theory doesn’t say whether an individual event will definitely happen or not. So is quantum theory complete, as Einstein thought, in which case we should try to complete the theory by refining the recipe, or are the individual events really totally random?

Einstein didn’t like the idea that God plays dice with the universe, as he characterized the orthodox Copenhagen interpretation of quantum mechanics adopted by Niels Bohr, Werner Heisenberg, and colleagues. He wrote to his friend the physicist Max Born:

I find the idea quite intolerable that an electron exposed to radiation should choose of its own free will, not only its moment to jump off, but also its direction. In that case, I would rather be a cobbler, or even an employee in a gaming house, than a physicist.

But Einstein was wrong. Consider this puzzle. Could you rig pairs of coins according to some recipe so that if Alice and Bob, separated by any distance, each toss a coin from a rigged pair heads up, one coin lands heads and the other tails, but if they toss the coins any other way (both tails up, or one tails up and the other heads up), they land the same? It turns out that if each coin is designed to land in any way at all that does not depend on the paired coin or how the paired coin is tossed—if each coin has its own “being-thus,” as Einstein put it—you couldn’t get the correlation right for more than 75% of the tosses. This is a version of Bell’s theorem, proved by John Bell in 1964.

Einstein

What has this got to do with quantum randomness? The coin correlation is actually a “superquantum” correlation called a PR-correlation, after Sandu Popescu and Daniel Rohrlich who came up with the idea. Quantum particles aren’t correlated in quite this way, but measurements on pairs of photons in an “entangled” quantum state can produce a correlation that is close to the coin correlation. If Alice and Bob use entangled photons rather than coins, they could simulate the coin correlation with a success rate of about 85% by measuring the polarizations of the photons in certain directions.

Suppose Alice measures the polarizations of her photons in direction A = 0 or A′ = π/4 instead of tossing her coin tails up or heads up, and Bob measures in the direction B = π/8 or B′ = −π/8 instead of tossing his coin tails up or heads up. Then the angle between Alice’s measurement direction and Bob’s measurement direction is π/8, except when Alice measures in the direction A′ and Bob measures in the direction B′, in which case the angle is 3π/8. According to the quantum recipe for probabilities, the probability that the photon polarizations are the same when they are measured in directions π/8 apart is cos2(π/8), and the probability that the photon polarizations are different when they are measured in directions 3π/8 apart is sin2(3π/8) = cos2(π/8). So the probability that Alice and Bob get outcomes + or − corresponding to heads or tails that mimic the coin correlation is cos2(π/8), which is approximately .85.

Bell’s theorem tells us that this pattern of measurement outcomes is closer to the coin correlation pattern than any possible recipe could produce. So God does play dice, and events involving entangled quantum particles are indeed totally random!

BubTanya Bub is founder of 48th Ave Productions, a web development company. She lives in Victoria, British Columbia. Jeffrey Bub is Distinguished University Professor in the Department of Philosophy and the Institute for Physical Science and Technology at the University of Maryland, where he is also a fellow of the Joint Center for Quantum Information and Computer Science. His books include Bananaworld: Quantum Mechanics for Primates. He lives in Washington, DC. They are the authors of Totally Random: Why Nobody Understands Quantum Mechanics (A Serious Comic on Entanglement).

Celebrate Pi Day with Books about Einstein

Pi Day is coming up! Mathematicians around the world celebrate on March 14th because the date represents the first three digits of π: 3.14.

In Princeton, Pi Day is a huge event even for the non-mathematicians among us, given that March 14 is also Albert Einstein’s birthday. Einstein was born on March 14, 1879, in Ulm, in the German Empire. He turns 139 this year! If you’re in the Princeton area and want to celebrate, check out some of the festivities happening around town:

Saturday, 3/10/18

  • Apple Pie Eating Contest, 9:00 a.m., McCaffrey’s (301 North Harrison Street). Arrive by 8:45 a.m. to participate.
  • Einstein in Princeton Guided Walking Tour, 10:00 a.m. Call Princeton Tour Company at (855) 743-1415 for details.
  • Einstein Look-A-Like Contest, 12:00 p.m., Nassau Inn. Arrive early to get a spot to watch this standing-room-only event!
  • Pi Recitation Contest, 1:30 p.m., Prince William Ballroom, Nassau Inn. Children ages 12 and younger may compete. Register by 1:15 p.m.
  • Pie Throwing Event, 3:14 p.m., Palmer Square. Proceeds to benefit the Princeton Educational Fund Teacher Mini-Grant Program.
  • Cupcake Decorating Competition, 4:00 p.m., House of Cupcakes (34 Witherspoon Street). The winner receives one free cupcake each month for the rest of the year.

Wednesday, 3/14/18

  • Princeton School Gardens Cooperative Fundraiser, 12:00 p.m. to 6:00 p.m., The Bent Spoon (35 Palmer Square West) and Lillipies (301 North Harrison Street). All proceeds from your afternoon treat will be donated to the Princeton School Gardens Cooperative.
  • Pi Day Pop Up Wedding/Vow Renewal Ceremonies, 3:14 p.m. to 6:00 p.m., Princeton Pi (84 Nassau Street). You must pre-register by contacting the Princeton Tour Company.

Not into crowds, or pie? You can also celebrate this multifaceted holiday by picking up one of PUP’s many books about Albert Einstein! In 1922, Princeton University Press published Einstein’s The Meaning of Relativity, his first book produced by an American publisher. Since then, we’ve published numerous works by and about Einstein.

The books and collections highlighted here celebrate not only his scientific accomplishments but also his personal reflections and his impact on present-day scholarship and technology. Check them out and learn about Einstein’s interpersonal relationships, his musings on travel, his theories of time, and his legacy for the 21st century.

Volume 15 of the Collected Papers of Albert Einstein, forthcoming in April 2018, covers one of the most thrilling two-year periods in twentieth-century physics, as matrix mechanics—developed chiefly by W. Heisenberg, M. Born, and P. Jordan—and wave mechanics—developed by E. Schrödinger—supplanted the earlier quantum theory. The almost one hundred writings by Einstein, of which a third have never been published, and the more than thirteen hundred letters show Einstein’s immense productivity and hectic pace of life.

Einstein quickly grasps the conceptual peculiarities involved in the new quantum mechanics, such as the difference between Schrödinger’s wave function and a field defined in spacetime, or the emerging statistical interpretation of both matrix and wave mechanics. Inspired by correspondence with G. Y. Rainich, he investigates with Jakob Grommer the problem of motion in general relativity, hoping for a hint at a new avenue to unified field theory.

Readers can access Volumes 1-14 of the Collected Papers of Albert Einstein online at The Digital Einstein Papers, an exciting new free, open-access website that brings the writings of the twentieth century’s most influential scientist to a wider audience than ever before. This unique, authoritative resource provides full public access to the complete transcribed, annotated, and translated contents of each print volume of the Collected Papers. The volumes are published by Princeton University Press, sponsored by the Hebrew University of Jerusalem, and supported by the California Institute of Technology. Volumes 1-14 of The Collected Papers cover the first forty-six years of Einstein’s life, up to and including the years immediately before the final formulation of new quantum mechanics. The contents of each new volume will be added to the website approximately eighteen months after print publication. Eventually, the website will provide access to all of Einstein’s writings and correspondence accompanied by scholarly annotation and apparatus, which are expected to fill thirty volumes.

The Travel Diaries of Albert Einstein is the first publication of Albert Einstein’s 1922 travel diary to the Far East and Middle East, regions that the renowned physicist had never visited before. Einstein’s lengthy itinerary consisted of stops in Hong Kong and Singapore, two brief stays in China, a six-week whirlwind lecture tour of Japan, a twelve-day tour of Palestine, and a three-week visit to Spain. This handsome edition makes available, for the first time, the complete journal that Einstein kept on this momentous journey.

The telegraphic-style diary entries—quirky, succinct, and at times irreverent—record Einstein’s musings on science, philosophy, art, and politics, as well as his immediate impressions and broader thoughts on such events as his inaugural lecture at the future site of the Hebrew University in Jerusalem, a garden party hosted by the Japanese Empress, an audience with the King of Spain, and meetings with other prominent colleagues and statesmen. Entries also contain passages that reveal Einstein’s stereotyping of members of various nations and raise questions about his attitudes on race. This beautiful edition features stunning facsimiles of the diary’s pages, accompanied by an English translation, an extensive historical introduction, numerous illustrations, and annotations. Supplementary materials include letters, postcards, speeches, and articles, a map of the voyage, a chronology, a bibliography, and an index.

Einstein would go on to keep a journal for all succeeding trips abroad, and this first volume of his travel diaries offers an initial, intimate glimpse into a brilliant mind encountering the great, wide world. 

More than fifty years after his death, Albert Einstein’s vital engagement with the world continues to inspire others, spurring conversations, projects, and research, in the sciences as well as the humanities. Einstein for the 21st Century shows us why he remains a figure of fascination.

In this wide-ranging collection, eminent artists, historians, scientists, and social scientists describe Einstein’s influence on their work, and consider his relevance for the future. Scientists discuss how Einstein’s vision continues to motivate them, whether in their quest for a fundamental description of nature or in their investigations in chaos theory; art scholars and artists explore his ties to modern aesthetics; a music historian probes Einstein’s musical tastes and relates them to his outlook in science; historians explore the interconnections between Einstein’s politics, physics, and philosophy; and other contributors examine his impact on the innovations of our time. Uniquely cross-disciplinary, Einstein for the 21st Century serves as a testament to his legacy and speaks to everyone with an interest in his work. 

The contributors are Leon Botstein, Lorraine Daston, E. L. Doctorow, Yehuda Elkana, Yaron Ezrahi, Michael L. Friedman, Jürg Fröhlich, Peter L. Galison, David Gross, Hanoch Gutfreund, Linda D. Henderson, Dudley Herschbach, Gerald Holton, Caroline Jones, Susan Neiman, Lisa Randall, Jürgen Renn, Matthew Ritchie, Silvan S. Schweber, and A. Douglas Stone.

On April 6, 1922, in Paris, Albert Einstein and Henri Bergson publicly debated the nature of time. Einstein considered Bergson’s theory of time to be a soft, psychological notion, irreconcilable with the quantitative realities of physics. Bergson, who gained fame as a philosopher by arguing that time should not be understood exclusively through the lens of science, criticized Einstein’s theory of time for being a metaphysics grafted on to science, one that ignored the intuitive aspects of time. Jimena Canales tells the remarkable story of how this explosive debate transformed our understanding of time and drove a rift between science and the humanities that persists today.

The Physicist and the Philosopher is a magisterial and revealing account that shows how scientific truth was placed on trial in a divided century marked by a new sense of time.

 

After completing the final version of his general theory of relativity in November 1915, Albert Einstein wrote a book about relativity for a popular audience. His intention was “to give an exact insight into the theory of relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical apparatus of theoretical physics.” The book remains one of the most lucid explanations of the special and general theories ever written.

This new edition features an authoritative English translation of the text along with an introduction and a reading companion by Hanoch Gutfreund and Jürgen Renn that examines the evolution of Einstein’s thinking and casts his ideas in a broader present-day context.

Published on the hundredth anniversary of general relativity, this handsome edition of Einstein’s famous book places the work in historical and intellectual context while providing invaluable insight into one of the greatest scientific minds of all time.