FROM THE MARCH 2009 ISSUE

They Don't Make Homo Sapiens Like They Used To

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By Kathleen McAuliffe|Monday, February 09, 2009

Our species—and individual races—have recently made

big evolutionary changes to adjust to new pressures.

For decades the consensus view—among the public as well as the world’s preeminent biologists—has been that human evolution is over. Since modern Homo sapiensemerged 50,000 years ago, “natural selection has almost become irrelevant” to us, the influential Harvard paleontologist Stephen Jay Gould proclaimed. “There have been no biological changes. Everything we’ve called culture and civilization we’ve built with the same body and brain.” This view has become so entrenched that it is practically doctrine. Even the founders of evolutionary psychology, Leda Cosmides and John Tooby, signed on to the notion that our brains were mostly sculpted during the long period when we were hunter-gatherers and have changed little since. “Our modern skulls house a Stone Age mind,” they wrote in a background piece on the Center for Evolutionary Psychology at the University of California at Santa Barbara.

So to suggest that humans have undergone an evolutionary makeover from Stone Age times to the present is nothing short of blasphemous. Yet a team of researchers has done just that. They find an abundance of recent adaptive mutations etched in the human genome; even more shocking, these mutations seem to be piling up faster and ever faster, like an avalanche. Over the past 10,000 years, their data show, human evolution has occurred a hundred times more quickly than in any other period in our species’ history.

The new genetic adaptations, some 2,000 in total, are not limited to the well-recognized differences among ethnic groups in superficial traits such as skin and eye color. The mutations relate to the brain, the digestive system, life span, immunity to pathogens, sperm production, and bones—in short, virtually every aspect of our functioning.

Many of these DNA variants are unique to their continent of origin, with provocative implications. “It is likely that human races are evolving away from each other,” says University of Utah anthropologist Henry Harpending, who coauthored a major paper on recent human evolution. “We are getting less alike, not merging into a single mixed humanity.”

Harpending theorizes that the attitudes and customs that distinguish today’s humans from those of the past may be more than just cultural, as historians have widely assumed. “We aren’t the same as people even a thousand or two thousand years ago,” he says. “Almost every trait you look at is under strong genetic influence.”

Not surprisingly, the new findings have raised hackles. Some scientists are alarmed by claims of ethnic differences in temperament and intelligence, fearing that they will inflame racial sensitivities. Other researchers point to limitations in the data. Yet even skeptics now admit that some human traits, at least, are evolving rapidly, challenging yesterday’s hallowed beliefs.

A BONE TO PICK

Bones don’t lie. John Hawks of the University of Wisconsin at Madison likes evidence he can put his hands on, so he takes me on a tour of the university’s bone laboratory. There, the energetic 36-year-old anthropologist unlocks a glass case and begins arranging human skulls and other skeletal artifacts—some genuine fossils, others high-quality reproductions—on a counter according to their age. Gesturing toward these relics, which span the past 35,000 years, Hawks says, “You don’t have to look hard to see that teeth are getting smaller, skull size is shrinking, stature is getting smaller.”

These overriding trends are similar in many parts of the world, but other changes, especially over the past 10,000 years, are distinct to specific ethnic groups. “These variations are well known to forensic anthropologists,” Hawks says as he points them out: In Europeans, the cheekbones slant backward, the eye sockets are shaped like aviator glasses, and the nose bridge is high. Asians have cheekbones facing more forward, very round orbits, and a very low nose bridge. Australians have thicker skulls and the biggest teeth, on average, of any population today. “It beats me how leading biologists could look at the fossil record and conclude that human evolution came to a standstill 50,000 years ago,” Hawks says.

By his account, Hawks’s theory of accelerated human evolution owes its genesis to what he could see with his own eyes. But his radical view was also influenced by newly emerging genetic data. Thanks to stunning advances in sequencing and deciphering DNA in recent years, scientists had begun uncovering, one by one, genes that boost evolutionary fitness. These variants, which emerged after the Stone Age, seemed to help populations better combat infectious organisms, survive frigid temperatures, or otherwise adapt to local conditions. And they were popping up with surprising frequency.

Taken together, the skeletal and genetic evidence convinced Hawks that the ruling “static” view of recent human evolution was not only wrong but also quite possibly the opposite of the truth. He discussed his ideas with Harpending, his former postdoc adviser at the University of Utah, and Gregory Cochran, a physicist and adjunct professor of anthropology there. They both agreed with Hawks’s interpretation. But why, they wondered, might evolution be picking up speed? What could be fueling the trend?

Then one day, as Hawks and Cochran mulled over the matter in a phone conversation, inspiration struck. “At exactly the same moment, both of us realized, gee, there’s a lot more people on the planet in recent times,” Hawks recalls. “In a large population you don’t have to wait so long for the rare mutation that boosts brain function or does something else desirable.”

The three scientists reviewed the demographic data. Ten thousand years ago, there were fewer than 10 million people on earth. That figure soared to 200 million by the time of the Roman Empire. Since around 1500 the global population has been rising exponentially, with the total now surpassing 6.7 billion. Since mutations are the fodder on which natural selection acts, it stands to reason that evolution might happen more quickly as our numbers surge. “What we were proposing was nothing new to animal breeders of the 19th century,” Cochran notes. “Darwin himself emphasized the importance of maintaining a large herd for selecting favorable traits.”

The logic behind the notion was undeniably simple, but at first glance it seemed counterintuitive. The genomes of any two individuals on the planet are more than 99.5 percent the same. Put another way, less than 0.5 percent of our DNA varies across the globe. That is often taken to mean that we have not evolved much recently, Cochran says, “but keep in mind that the human and chimp genomes differ by only about 1 to 2 percent—and nobody would call that a minor difference. None of this conflicts with the idea that human evolution might be accelerating.”

CULTURE SHOCK

If their hunch was correct, the scientists wondered a few years back, how could they prove it? As it turned out, it was an opportune time to pose that question.

For decades theories about human evolution had proliferated despite the absence of much, if any, hard evidence. But now there were finally human genetic data banks large enough to allow the scientists to put their assumptions to the test. One of these, the International Haplotype Map, cataloged differences in DNA collected from 270 people of Japanese, Han Chinese, Nigerian, and northern European descent. Moreover, Harpending knew two geneticists—Robert Moyzis of the University of California at Irvine, and Eric Wang of Veracyte Inc. in South San Francisco—who were at the forefront of developing new computational methods for mining this data to estimate the rate of evolution. Harpending contacted them to see if they would be willing to collaborate on a study.

Human races are evolving away from each other. We are

getting less alike, not merging into a single mixed humanity.

The West Coast scientists were intrigued. On the basis of their own preliminary data, they, too, suspected that the pace of human evolution was accelerating. But they had arrived at the same crossroads by a different route. “We were focused on cultural shifts as a prime driving force of our evolution,” Moyzis says. As he explains it, an exceptional period in the history of our species occurred about 50,000 years ago. Humans were pouring forth from Africa and fanning out across the globe, eventually taking up residence in niches as diverse as the Arctic Circle, the rain forests of the Amazon, the foothills of the Himalayas, and the Australian outback. Improvements in clothing, shelter, and hunting techniques paved the way for this expansion.

Experts agree on that much but then part ways. These innovations, prominent evolutionary theorists insist, insulated us from the relentless winnowing of natural selection, thereby freeing us from the Darwinian rat race. But Moyzis and Wang looked at the same developments and came to the opposite conclusion. In our far-flung domains, they point out, humans presumably encountered starkly different selective forces as they adjusted to novel foods, predators, climates, and terrains. And as we became more innovative, the pressure to change only intensified. “If you’re a human, what is your environment but culture?” Moyzis asks. “The faster our ingenuity alters our habitat, the quicker we have to adapt in response.”

As for the role of population size in spurring our evolution, he and Wang had not given it much thought, but they saw the idea as complementary to their own view, since cultural innovations allowed more people to survive. So when Harpending’s group came calling, Moyzis says, “we were happy to combine ideas and work together.”

To study natural selection, the team combed the International Haplotype Map for long stretches of DNA flanked by a single nucleotide polymorphism (SNP, or “snip”)—that is, an altered base, or “letter,” in the genetic alphabet. When the exact same genetic block is present in at least 20 percent of a population, according to the scientists, it indicates that something about that block has conferred a survival advantage; otherwise, it would not have become so prevalent. Because genes are reshuffled with each generation, Moyzis adds, the presence of large unchanged blocks of DNA means they were probably inherited recently. In the parlance of scientists, it is “a signature of natural selection.”

Scanning genomes in the haplotype map for these clues, the researchers discovered that 7 percent of human genes fit the profile of a recent adaptation, with most of the change happening from 40,000 years ago to the present. As predicted, these apparent adaptations occurred at a rate that jumped almost exponentially in prevalence as the human population exploded. To rule out the prevailing view—that our evolution has proceeded at a steady rate all along—the scientists ran an additional check. They performed a computer simulation to see what would have happened if humans had evolved at modern rates ever since we diverged from chimpanzees 6 million years ago. The steady-state test led to a nonsensical result: The difference between the two species today would be 160 times greater than it actually is. To Moyzis and the others, the results confirmed that human evolution had only recently hit the accelerator.

MORPHING AT HIGH SPEED

All of these findings mesh beautifully with the notion that cultural and demographic shifts sparked our transformation. Our exodus out of Africa, for example, paved the way for one of the most obvious markers of race, skin hue. As scientists widely recognize, paler complexions are a genetic adjustment to low light: People with dark skin have trouble manufacturing vitamin D from ultraviolet radiation in northern latitudes, which makes them more susceptible to serious bone deformities. Consequently, Europeans and Asians over the last 20,000 years evolved lighter skin through two dozen different mutations that decrease production of the skin pigment melanin.

Similarly, the gene for blue eyes codes for paler skin coloring in many vertebrates and hence might have piggybacked along with lighter skin. Clearly something made blue eyes evolutionarily advantageous in some environments. “No one on earth had blue eyes 10,000 years ago,” Hawks says.

The transition to an agrarian existence after hundreds of thousands of years of hunting and gathering was another key catalyst of evolution. Once people began keeping cattle herds, for example, it became an advantage to derive nutrient calories from milk throughout life rather than only as an infant or toddler suckling at its mother’s breast. A mutation that arose about 8,000 years ago in northern Europe, Hawks says, allowed adults to digest lactose (the main sugar in milk), and it propagated rapidly, allowing the rise of the modern dairy industry. Today the gene for lactose digestion is present in 80 percent of Europeans but in just 20 percent of Asians and Africans.

Agriculture may have opened up other pathways for evolution by supporting an ever-growing population that eventually began to congregate in the first cities. In crowded, filthy quarters, pathogens spread like wildfire. Suddenly there were epidemics of smallpox, cholera, typhus, and malaria, diseases unknown to hunter-gatherers, and so began an evolutionary arms race to fend off the assault through superior immunity.

“The clearest example of that is malaria,” Hawks says. “The disease is about 35,000 years old, with the most lethal form of it just 5,000 years old.” Yet in sub-Saharan Africa and other regions where it is endemic, “people have already developed 25 new genes that protect against malaria, including the Duffy blood type, an entirely new blood group,” he notes. More recently, HIV resistance has appeared due to a genetic mutation now found in 10 percent of Europeans. Scientists speculate that the variant may have originally evolved as a protection against smallpox.

Paralleling the constant war against pathogens, human sperm may also be evolving at high speed, driven by the race to get to the egg before another man’s sperm. “It could be that cities create more sexual partners, which means fiercer competition among males,” Hawks says. Because sperm can fertilize an egg up to 24 hours after being ejaculated in the vagina, a woman who copulates with two or more partners in close succession is setting up the very conditions that pit one man’s sperm against another’s. Hawks infers that “sperm today is very different from sperm even 5,000 years ago.” Newly selected mutations in genes controlling sperm production show up in every ethnic group he and his team have studied; those genes may affect characteristics including abundance, motility, and viability. The selection for “super sperm,” Hawks says, provides further corroboration that our species is not particularly monogamous—a view widely shared by other anthropologists.

At the other end of the human life span, “genes that help us live longer get selected,” Hawks reports. This may seem counterintuitive, since evolutionary biologists long assumed that the elderly do not contribute to the gene pool and hence are invisible to natural selection. But as studies of the Hadza people of Tanzania and other groups suggest, children doted on by their grandmothers—receiving extra provisions and care—are more likely to survive and pass on their grandmothers’ genes for longevity. (Grandfathers were less involved with their grandchildren in the cultures studied, so the phenomenon is known as the “grandmother effect.”) Old men can also pass on their genes by mating with younger women.

As agriculture became established and started creating a reliable food supply, Hawks says, more men and women would have begun living into their forties and beyond—jump-starting the selection pressure for increased life span. In support of that claim, Moyzis is currently performing a genetic analysis of men and women in their nineties who are of European ancestry. He has traced many early-onset forms of cancer, heart disease, and Alzheimer’s to older human gene variants. “The idea is that people with more modern variants tend to have greater resistance to these chronic illnesses of old age and should be overrepresented in the age 90-plus population,” Moyzis says.

EVOLUTION AND THE BRAIN

Perhaps the most incendiary aspect of the fast-evolution research is evidence that the brain may be evolving just as quickly as the rest of the body. Some genes that appear to have been recently selected, Moyzis and his collaborators suggest, influence the function and development of the brain. Other fast-changing genes—roughly 100—are associated with neurotransmitters, including serotonin (a mood regulator), glutamate (involved in general arousal), and dopamine (which regulates attention). According to estimates, fully 40 percent of these neurotransmitter genes seem to have been selected in the past 50,000 years, with the majority emerging in just the past 10,000 years.

Addressing the hot-potato question—What might these changes signify?—Moyzis and Wang theorize that natural selection probably favored different abilities and dispositions as modern groups adapted to the increasingly complex social order ushered in by the first human settlements.

When people in hunter-gatherer communities have a conflict, Moyzis reports, usually one of them will just walk away. “There is a great deal of fluidity in these societies,” he says, “so it’s easy to join another group.” But with the establishment of the first farming communities, we put down roots figuratively as well as literally. “You can’t just walk away,” Moyzis notes, a fact that would have created selection pressure to revise the mechanisms regulating aggression, such as the glutamate pathways involved in arousal. “When you domesticate animals, you tend to change genes in that system,” he says.

For decades theories about human evolution proliferated 

in the absence of hard evidence, but now human genetic

data banks are large enough to put assumptions to the test.

The rise of settlements also promoted the breakdown of labor into specialized jobs. That, coupled with food surpluses from farming, led to systems of trade and the need to track the flow of resources, which in turn could have selected for individuals with specific cognitive strengths. “Mathematical ability is very important when it comes to keeping track of crops and bartering,” Wang says. “Certainly your working memory has to be better. You have to remember who owes you what.” The researchers point to China’s Mandarin system, a method of screening individuals for positions as tax collectors and other government administrators. For nearly 2,000 years, starting in A.D. 141, the sons of a broad cross section of Chinese society, including peasants and tradesmen, took the equivalent of standardized tests. “Those who did well on them would get a good job in the civil service and oftentimes had multiple wives, while the other sons remained in a rice field,” Moyzis says. “Probably for thousands of years in some cultures, certain kinds of intellectual ability may have been tied to reproductive success.”

Harpending and Cochran had previously—and controversially—marshaled similar evidence to explain why Ashkenazi Jews (those of northern European descent) are overrepresented among world chess masters, Nobel laureates, and those who score above 140 on IQ tests. In a 2005 article in the Journal of Biosocial Science, the scientists attributed Ashkenazis’ intellectual distinction to a religious and cultural environment that blocked them from working as farm laborers in central and northern Europe for almost a millennium, starting around A.D. 800. As a result, these Jews took jobs as moneylenders and financial administrators of estates. To make a profit, Harpending says, “they had to be good at evaluating properties and market risks, all the while dodging persecution.” Those who prospered in these mentally demanding and hostile environments, the researchers posit, would have left behind the most offspring. Critics note that the association between wealth and intelligence in this interpretation is circumstantial, however.

Stronger evidence that natural selection has continued to shape the brain in recent epochs comes from studies of DRD4, a mutation in a neurotransmitter receptor that Moyzis, Wang, and many others have linked to attention-deficit/hyperactivity disorder (ADHD). Children diagnosed with ADHD are twice as likely to carry the variant gene as those without the diagnosis. DRD4 makes a receptor in the brain less effective in bonding to dopamine, which might explain why Ritalin, which increases the amount of dopamine in the space between neurons, is often helpful in treating the problem.

Sequencing studies suggest that the DRD4 mutation arose 50,000 years ago, just as humans were spreading out of Africa. Its prevalence tends to increase the farther a population is from Africa, leading some investigators to dub it “the migratory gene.” At least one allele (or copy of the gene) is carried by 80 percent of some South American populations. In contrast, the allele is present in 40 percent of indigenous populations living farther north in the Americas and in just 20 percent of Europeans and Africans. Children with the mutation tend to be more restless than other youngsters and to score higher on tests of novelty-seeking and risk-taking, all traits that might have pushed those with the variant to explore new frontiers.

In the context of a modern classroom, it may be hard to understand why kids who appear distractible and disruptive might have a survival advantage. But research shows people with DRD4 do not differ in intelligence from national norms; if anything, they may on average be smarter. Moreover, behavior that may seem like a drawback today may not have been so in ancient environments. When broaching foreign terrain filled with unknown predators, “having the trait of focusing on multiple directions might have been a good thing,” Wang says. “People focused in one direction might get eaten.”

Humans in far-flung domains encountered starkly different selective

forces, adjusting to novel foods, predators, climates, and terrains.

NOT SO FAST

Despite all these clues that human evolution has continued and accelerated into modern times, many evolutionary biologists remain deeply skeptical of the claims. Their resistance comes from several directions.

Some independent experts caution that the tools for studying the human genome remain in their infancy, and reliably detecting genomic regions that have been actively selected is a challenging problem. The hypothesis that human evolution is accelerating “all rests on being able to identify recent areas of the genome under natural selection fairly accurately,” says human geneticist Jonathan Pritchard of the University of Chicago. And that, he warns, is tricky, involving many different assumptions (about population sizes on different continents, for instance) in the poorly documented period before recorded history.

Given such uncertainties, researchers are more likely to be persuaded that a mutation has been recently selected if they understand its function and if its rise in prevalence meshes well with known human migratory routes. Genetic variants fitting that description include those coding for lighter skin coloring, resistance to diseases such as malaria, and metabolic changes related to the digestion of novel foods. There is broad consensus that these represent genuine examples of recent adaptations.

Question marks surround many other recent genetic changes. We know almost nothing about most regions of the genome that have been identified as potential targets of natural selection, observes Sarah Tishkoff, a geneticist at the University of Pennsylvania School of Medicine. Until scientists understand more of the landscape of the human genome, she says, she will have a hard time believing that adaptive genetic differences between ethnic groups have mushroomed over the past 20,000 years. She is particularly wary of claims that selective pressures recently played a role in shaping different cognitive abilities and temperaments among ethnic groups. “We have no strong evidence of that,” Tishkoff says.

Francis Collins, who until last year headed the National Human Genome Research Institute at the National Institutes of Health, concurs. “This is not a place to idly speculate about possibilities,” he says. “When it comes to brain functioning, let’s be honest: That is a tinderbox of possible explosive reactions based upon a very unpretty history of discrimination and of demagogues using information that they claimed came from biology in order to put down some groups that they didn’t like.” Even when it comes to the ADHD connection, Collins is a skeptic. “I want to see DRD4 replicated by independent investigators on an independent sample of children,” he says.

In some circles, Moyzis says, to suggest that natural selection is acting on the human brain is tantamount to heresy—an incredible hypothesis that demands extraordinary proof. Harpending, Cochran, and their collaborators are mystified as to what it is that makes their theory so incredible. “I would turn that statement on its head,” Moyzis says. “The extraordinary claim is that evolution somehow stopped once we developed culture.” Coch­ran says, “You’re allowed to change, but only if it’s below the neck. Many people think the brain has to be immune to natural selection; if it isn’t, they don’t want to hear it.”

Harvard University evolutionary biologist Pardis Sebati defends that view. “The immune system and skin interact directly with the outside world,” she says. “They are our first line of defense.” Based on the current evidence, she concludes, sunlight and pathogens were among the strongest selective forces, and skin and the immune system underwent the most dramatic change; evolutionary pressures on the brain are not nearly as clear-cut. As Harvard geneticist David Altshuler wrote in response to one of Sebati’s articles, “It’s reassuring that differences between the races seem to be mostly skin deep.”

The “reassuring” quality of that belief makes those in the opposing camp wonder if some of the logic of skeptics is tinged with wishful thinking. Harvard’s Steven Pinker, the celebrated author of The Blank Slate and an expert on the evolution of language and the mind, addressed that point in an interview in New Scientistmagazine: “People, including me, would rather believe that significant human biological evolution stopped between 50,000 and 100,000 years ago, before the races diverged, which would ensure that racial and ethnic groups are biologically equivalent.”

Many scientists apparently worry that proof of divergent brain evolution could be so racially polarizing that we, as a society, would almost be better off in the dark. Hawks responds that the best safeguard against bigotry is educating the public. He thinks we understand enough about human genetics to know that the notion of racial superiority is absurd. Intelligence, he argues, is not a single trait but a vast suite of abilities, and each ancestral environment may have favored a different set of talents. What is sorely needed, he says, is “an ecological framework” to interpret the results. “Groups are best adapted to their own environment, which eliminates the question of superiority.” Even he concedes, though, that communicating the nuances will be no easy task.

“Whatever we find,” Wang says, “it would never be justification for abandoning the egalitarian value that all individuals, regardless of their ethnicity, are deserving of the same rights and opportunities.” Moyzis expands on that line of reasoning, putting a sunny spin on the group’s findings. “It would be boring if all the races were fundamentally the same,” he argues. “It’s exciting to think that they bring different strengths and talents to the table. That is part of what makes melting-pot cultures like our own so invigorating and creative.”

Of course, in melting-pot cultures all kinds of ethnic groups intermingle freely, and the children who result literally meld our DNA together. Even if those groups were diverging, international travel is now causing the diversity to get lost in the genetic reshuffling. “That’s the ultimate irony,” Moyzis says. “By the time we finally settle this debate, we’ll all be such a mixture of genes that we won’t care.”

THE HUMAN JOURNEY

Y-DNA Human Journey

Why is There Something Rather Than Nothing?

My most recent articles these past several months have been in answer to a Calvinist Pastor/Teacher's assertion that determinism, literalism and ex nihilo creation is the only way to go when answering the creeds of the church and interpreting the church's many theological assertions. I have contended that this kind of thinking is closed-minded, subjective, and misleading in its struggles to grasp the newer contemporary theologies which have come forth over the past 170 years (c.1850 forward). For these reasons and more I have been detailing why process theology and process thought has been helpful in fundamentally rethinking how Christianity should behave, preach, and witness to the world about itself. If not, then for many Christians, they have artificially limited themselves, their faith, their God, and their Bible from any meaningfulness to this life or the next.

As such, I am very much interested in expanding the playing field while connecting contemporary articles to my own past articles I wrote many years ago under various topical listings (see right sidebar on blog). Below is an excellent article by Michael Shermer found on skeptic.com. It summarizes quite neatly the different arguments for God, for the creation of the cosmos, and allows a more open-ended conversation to the subject of biblical/evolutionary/cosmological teleology. Enjoy.

R.E. Slater

December 28, 2018

Why is There Something Rather Than Nothing?

https://www.skeptic.com/reading_room/why-is-there-something-rather-than-nothing/

By MICHAEL SHERMER

I

n my many debates with theists over the decades a handful of arguments for God’s existence are routinely articulated as “proofs” of divine providence. These include the cosmological argument (that all natural things are contingent on something else for their existence so there necessarily exists a being independent of nature), the ontological argument (that we can conceive of an absolutely perfect being means it must exist because existence is a necessary feature of perfection), the design argument (the universe is fine-tuned for life, and life contains design features, therefore God is the fine-tuner and intelligent designer of life), the moral argument (without God anything goes, with God there is objective morality), the consciousness argument (the qualitative experience—qualia—of consciousness cannot be explained by the activity of neurons, and abstract concepts like logic and mathematics exist separate from brains, therefore God must be the source), and others. All of these arguments (they are certainly not proofs in the mathematical sense) have counter-arguments made by philosophers over the centuries, but there is one that seems to trouble a great many thinkers of all persuasions, and that is why there should be anything at all. That is, all of the other arguments for God’s existence presume that something exists that needs explaining. The argument that asks why there is something rather than nothing underlies all the other arguments, and is cognitively challenging because it is simply not possible for existing beings to imagine not existing, not just themselves (which forms the cognitive foundation of afterlife beliefs), but to imagine nothing existing at all. Go ahead and try it. Picture nothing. When I ask myself this question I start by visualizing dark empty space bereft of galaxies, stars, and planets, along with molecules and atoms. But this picture is incorrect because if there were no universe there would not only be no matter, but there would be no space or time (or space-time) either. There would be absolutely nothing, including no conscious being to observe the nothingness. Just… nothing. Whatever that is. This presents us with what is arguably the deepest of deep questions: why is there something rather than nothing? In his 1988 blockbuster book A Brief History of Time, the late Cambridge theoretical physicist Stephen Hawking put it this way:

What is it that breathes fire into the equations and makes a universe for them to describe? The usual approach of science of constructing a mathematical model cannot answer the questions of why there should be a universe for the model to describe. Why does the universe go to all the bother of existing?¹

Even if it could be established that something must exist, this does not necessarily mean that the something must be our universe with our particular laws of nature that give rise to atoms, stars, planets, and people. There could be universes whose laws of nature permit time and space but no matter or light; such universes could not be perceived because there would be no one to perceive the darkness. Our universe has particular properties suited to planets and people. According to England’s Astronomer Royal Sir Martin Rees, there are at least six constituents that are necessary for “our emergence from a simple Big Bang,” including (1) Ω (omega), the amount of matter in the universe = 1: if Ω was greater than 1 it would have collapsed long ago and if Ω was less than 1 no galaxies would have formed. (2) ε (epsilon), how firmly atomic nuclei bind together = .007: if ε were even fractionally different matter could not exist. (3) D, the number of dimensions in which we live = 3. (4) N, the ratio of the strength of electromagnetism to that of gravity = 10³⁹: if N were smaller the universe would be either too young or too small for life to form. (5) Q, the fabric of the universe = 1/100,000: if Qwere smaller the universe would be featureless and if Q were larger the universe would be dominated by giant black holes. (6) λ (lambda), the cosmological constant, or “antigravity” force that is causing the universe to expand at an accelerating rate = 0.7: if λ were larger it would have prevented stars and galaxies from forming.²

The most common reason invoked for our universe’s “fine-tuning” is the “anthropic principle,” most forcefully argued by the physicists John Barrow and Frank Tipler in their 1986 book The Anthropic Cosmological Principle: “It is not only man that is adapted to the universe. The universe is adapted to man. Imagine a universe in which one or another of the fundamental dimensionless constants of physics is altered by a few percent one way or the other? Man could never come into being in such a universe. That is the central point of the anthropic principle. According to the principle, a life-giving factor lies at the center of the whole machinery and design of the world.”³ So we really have two questions to answer: Why there is something rather than nothing, and Why this universe? Here are a number of responses, ranging from the philosophical to the scientific, that I have compiled from a number of sources, including a comprehensive taxonomic work by John Leslie and Robert Lawrence Kuhn titled The Mystery of Existence: Why is There Anything at All? that catalogues all extant explanations without religious, scientific, or philosophical prejudice.⁴

EXPLANATIONS FOR NOTHING

1. Nothing is Inconceivable

First, as I suggested above, just as it is not possible to conceive of what it is like to be dead, it is impossible to conceptualize nothing—no space, time, matter, light, darkness, or even any conscious beings to perceive the nothingness. As Robert Kuhn conceives it: “Not just emptiness, not just blankness, and not just emptiness and blankness forever, but not even the existence of emptiness, not even the meaning of blankness, and no forever.”⁵ Inconceivable.

2. Nothing is Something

The analytical philosopher Quentin Smith pointed out to Kuhn that it is a logical fallacy to talk about “nothing” as if it were “something”; that is, to suggest that “there might have been nothing” implies “it is possible that there is nothing.” As Kuhn articulates Smith’s argument: “‘There is’ means ‘something is.’ So ‘there is nothing’ means ‘something is nothing,’ which is a logical contradiction. His suggestion is to remove ‘nothing’ and replace it by ‘not something’ or ‘not anything,’ since one can talk about what we mean by ‘nothing’ by referring to something or anything of which there are no instances (i.e., the concept of ‘something’ has the property of not being instantiated). The common sense way to talk about Nothing is to talk about something and negate it, to deny that there is something.”⁶ Here we are bumping up against the problem of defining what we mean by “nothing” and the restrictions that language imposes on the problem. The very act of talking about “nothing” makes it a “something,” or else what are we talking about?

3. Nothing Would Include God’s Nonexistence

In Kuhn’s taxonomy of “nothings” he lists what categories of things might be included in “something” that would be negated by “nothing”: physical, mental, platonic, spiritual, and God. Physical: all matter, energy, space and time, and all the laws and principles that govern them (known and unknown). Mental: all kinds of consciousness and awareness (known and unknown). Platonic: all forms of abstract objects (numbers, logic, forms, propositions, possibilities—known and unknown). Spiritual and God: anything that could possibly fit this nonphysical category (all forms of religious and spiritual belief).⁷ If by “nothing” is meant no physical objects or matter of any kind, for example, there can still be energy from which matter may arise by natural forces guided by the laws of nature. Physicists, for example, talk about empty space as seething with virtual particles, from which particle-antiparticle pairs come into existence as a consequence of the Uncertainty Principle of quantum physics. From this “nothingness” universes may “pop” into existence.⁸ But if by “nothing” is meant that there is no physical, mental, platonic, or nonphysical entity of any kind, then there can be no God or gods, which means that there cannot be anything outside of nothing out of which to create something. If God is proposed to be outside of or preexisting the “nothing” from which the “something” was created, then why can’t the laws of nature that give rise to “somethings” (like universes) be outside of or preexisting nothing? Some theologians argue that God is a “necessity,” by which they mean it is impossible for God not to exist. This is the famous Ontological Argument for the existence of God, first proposed by St. Anselm of Canterbury in 1078, which defines God as “that than which nothing greater can be conceived.” The argument is that God is necessary because necessity is a higher form of perfection that can be conceived than is contingency.⁹ The argument has been refuted time and again. In his Dialogues Concerning Natural Religion, for example, the great Scottish Enlightenment philosopher David Hume countered: “Nothing, that is distinctly conceivable, implies a contradiction. Whatever we conceive as existent, we can also conceive as non-existent. There is no being, therefore, whose nonexistence implies a contradiction. Consequently there is no being, whose existence is demonstrable.”¹⁰ To my ears this is all just word play, armchair speculation of what we can or cannot conceive of without once looking out the window to see what is actually in nature that may confirm or disconfirm our imaginary ideas.¹¹ I can just as easily argue that the laws of nature are a necessity for existence because they give rise to the universe, which makes them “that than which nothing greater can be conceived.” Or that abstract objects like circles, squares, and rectangles and the geometric principles that govern them, or mathematical principles like 3 + 2 = 5, necessarily exist because the existence of a circle is a higher form of perfection than the nonexistence of a circle. If circles did not exist then what would the formula for the area of a circle, A = πr² , describe? In any case, the conception of “perfection” is once again bound by the cognitive restrictions of thought and language we faced with consciousness and nothingness. How can an imperfect being conceive of what perfection even means? Who knows what an extra-terrestrial intelligence with a brain ten times the size of ours would be capable of conceiving, or a post-Singularity AI with an intelligence capacity a million times greater than humans would be able to conceptualize?

4. God Did It Ex Nihilo

For the many millennia that people have been asking these questions the most common answer given was some version of “God did it”: a creator existed before the universe and brought it into existence ex nihilo—out of nothing. Revealingly, Genesis does not actually say that God created the universe ex nihilo—that is a later inference made by theologians. Genesis 1:1 reads simply: “In the beginning God created the heavens and the earth.” It does not elaborate on what God made the heavens and the earth out of, which theologians have presumed to be nothing, but that it is not stated in the Bible. As Skeptic magazine’s religion editor Tim Callahan notes, the Hebrew word for creation in Genesis 1:1 is “bara,” which can mean create but can also mean “choose” or “divide.” Callahan cites the Old Testament scholar Ellen van Wolde, who argues that the most accurate translation of “bara” is “separate,” so Genesis 1:1 should read “In the beginning God separated the heavens and the earth.”¹² This, says Callahan, better fits the context of Genesis 1, “in which the creation is presented as a series of separations: light is created and separated from darkness, the firmament of heaven is created to separate the waters above it from the waters below it, and the separation of land from water. This is followed by a series of creation events populating the separated realms—the land populated with plants, the firmament populated with heavenly bodies, the sea populated with fish and sea monsters, the air with birds, and the land, again, with animals—followed finally by the creation of humans in the image of God.”¹³ Even if one rejects this interpretation of Genesis 1:1 and opts for creation ex nihilo, this just begs the question of who or what created the creator? Theists retort that God is that which does not need to be created. But why can’t the universe be in the same ontological and epistemological category as God, wherein we could simply say that the universe is that which does not need to be created? Theists counter that the universe had a Big Bang beginning and everything that begins to exist has a cause. But not everything in the universe is strictly causal, such as some quantum effects, and even though our universe in its current state can be traced back to a Big Bang beginning that doesn’t mean there was not a previous universe that gave birth to our universe through the Big Bang. Theists also note that that the universe is a thing, whereas God is an agent or being. But don’t things and beings all need a causal explanation? Why should God be exempt from such causal reasoning? Because, rejoins the theist, God is supernatural—outside of space, time, and matter—whereas everything in the universe, and the universe itself, is natural—made up of space, time, and matter, so God and the universe are ontologically different. But if that is so, then how would we detect God with our instruments? If a supernatural deity used natural forces to, say, cure someone’s cancer by reprogramming the cancerous cells’ DNA, wouldn’t that make God nothing more than a skilled genetic engineer, along the lines of a sufficiently advanced ETI or far-future human in my earlier thought experiment? And if God used unknown supernatural forces to effect change in our natural world, how do they interact with the known forces of our universe? And if such supernatural forces could somehow stir the particles in our universe, shouldn’t we be able to detect them and thereby incorporate them into our theories about the natural world? If so, wouldn’t that bring God into the universe as a natural being and thus subject him to the search for a natural causal explanation for his existence? Finally, if God made the universe ex nihilo—literally out of nothing—then apparently it is possible for something to come from nothing, so this brings us back to searching for the best causal explanation for anything—natural or supernatural?

5. Natural vs. Supernatural Explanations of Something

The history of science has been one long and steady replacement of the supernatural with the natural. Weather events once attributed to the supernatural scheming of deities are now understood to be the product of natural forces of temperature and pressure. Plagues formerly ascribed to women cavorting with the devil are today known to be caused by bacteria and viruses. Mental illnesses previously imputed to demonic possession are currently sought in genes and neurochemistry. Accidents heretofore explained by fate, karma, or providence are nowadays accredited to probabilities, statistics, and risk. If we follow this trend to encompass all phenomena, what place is there for supernatural agents like gods and demons? Do we know enough to know that they cannot exist? Or is it possible there are unknown forces within our universe, or intentional agents outside of it that we have yet to discover? According to the physicist Sean Carroll, in his examination of The Big Picture: On the Origins of Life, Meaning, and the Universe Itself, “All of the things you’ve ever seen or experienced in your life—objects, plants, animals, people—are made of a small number of particles, interacting with one another through a small number of forces.”¹⁴Once you understand the fundamental laws of nature, such as the thermodynamic arrow of time and the Core Theory of particles and forces, you can scale up to planets and people, and even assess the likelihood that God, the soul, and the afterlife exist, which Carroll concludes is very low. But isn’t the history of science also strewn with the remains of failed theories like geocentrism (the Earth is the center of the solar system), phlogiston (a fire-like element that causes objects to burn), miasma (the “bad air” source of disease), spontaneous generation (fully formed living organisms can abruptly arise out of inanimate matter), and the luminiferous aether (the medium filling outer space for the propagation of light)? Yes, and that’s how we know we’re making progress. The postmodern belief that the very existence of such discarded ideas means that there is no objective reality and that all theories are equal is wronger than all of the wrong theories combined. I have called this Asimov’s Axiom, after an observation by the science writer Isaac Asimov:

When people thought the earth was flat, they were wrong. When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, then your view is wronger than both of them put together.¹⁵

There is real progress in science. Think of it as an expanding sphere of knowledge. As the sphere of the known expands into the aether of the unknown, the proportion of ignorance seems to grow—the more you know, the more you know how much you don’t know. But in this mathematical analogy note what happens when the radius of a sphere increases: the expansion of the surface area is squared while the increase in the volume is cubed. So as the sphere of scientific knowledge expands the volume of the known increases by a ratio of 3:2 over the surface area of the unknown. The more you know the more of the unknown becomes known. It is at this boundary where we can stake a claim of true progress in the history of science. Take the Core Theory of the forces and particles that make up the universe. This includes the four forces of gravity, electromagnetism, and the strong and weak nuclear forces, along with the Standard Model of elementary particles making up the nucleus of the atom: quarks, leptons, and bosons, plus the underlying Higgs boson. Carroll says this Core Theory is “indisputably accurate within a very wide domain of applicability,” such that “a thousand or a million years from now, whatever amazing discoveries science will have made, our descendants are not going to be saying ‘Ha-ha, those silly twenty-first-century scientists, believing in ‘neutrons’ and ‘electromagnetism’.” Thus, Carroll concludes that the laws of physics rule out supernatural and paranormal claims. Why? Because the particles and forces of nature don’t allow us to bend spoons, levitate, read minds, or perform miracles, and “we know that there aren’t new particles or forces out there yet to be discovered that would support them. Not simply because we haven’t found them yet, but because we definitely would have found them if they had the right characteristics to give us the requisite powers.”¹⁶ It is at the horizon where the known meets the unknown that we are tempted to inject supernatural forces to explain hitherto unsolved mysteries, but we must resist the temptation, for such efforts can never succeed, not even in principle. Humans have always filled in such gaps in our knowledge with gods, and it never leads to any useful or productive theory. Let us try to overcome this psychological propensity to fill in the gaps with supernatural forces and follow the path of science in searching for natural forces.

6. Nothing is Unstable, Something is Stable

Asking why there is something rather than nothing presumes “nothing” is the natural state of things out of which “something” needs an explanation. Maybe “something” is the natural state of things and “nothing” would be the mystery to be solved. As the physicist Victor Stenger notes in his book, The Fallacy of Fine Tuning: “Current cosmology suggests that no laws of physics were violated in bringing the universe into existence. The laws of physics themselves are shown to correspond to what one would expect if the universe appeared from nothing. There is something rather than nothing because something is more stable.”¹⁷In his 2012 book, A Universe From Nothing, the cosmologist Lawrence Krauss attempts to link quantum physics to Einstein’s gravitational theory of general relativity to explain the origin of something (including a universe) from nothing: “In quantum gravity, universes can, and indeed always will, spontaneously appear from nothing. Such universes need not be empty, but can have matter and [electromagnetic] radiation in them, as long as the total energy, including the negative energy associated with gravity [balancing the positive energy of matter], is zero.” And: “In order for the closed universes that might be created through such mechanisms to last for longer than infinitesimal times, something like inflation is necessary.” Observations have revealed that, in fact, the universe is flat (there is just enough matter to eventually halt its expansion), its energy is zero, and it underwent rapid inflation, or expansion, shortly after the Big Bang as described by inflationary cosmology. Thus, Krauss concludes, “quantum gravity not only appears to allow universes to be created from nothing—meaning…the absence of space and time—it may require them. ‘Nothing’—in this case no space, no time, no anything!—is unstable.”¹⁸ In his follow-up 2017 work, The Greatest Story Ever Told—So Far, Krauss notes that “Einstein was one of the first physicists to demonstrate that the classical notion of causation begins to break down at the quantum realm.” Although many physicists objected to the idea of something coming from nothing, Krauss adds that “this is precisely what happens with the light you are using to read this page. Electrons in hot atoms emit photons—photons that didn’t exist before they were emitted—which are emitted spontaneously and without specific cause. Why is it that we have grown at least somewhat comfortable with the idea that photons can be created from nothing without cause, but not whole universes?”¹⁹

EXPLANATIONS FOR OUR UNIVERSE

The anthropic principle invoked to explain our universe troubles most scientists because of its antithesis known as the “Copernican principle,” which states that we are not special. The anthropic principle puts humans right back in the center of the cosmos, not geographically but anthropocentrically—it is all about us. There are a number of counter-explanations for our universe that continue in the scientific tradition of defenestrating humans from the Tower of Babel.

1. Inconstant Constants

The various numbers invoked in the “fine-tuning” argument for our universe as being special, such as the speed of light and Planck’s constant, are, in fact, arbitrary numbers that can be configured in different ways so that their relationship to the other constants do not appear to be so remarkable. As well, such constants may be inconstantover vast spans of time, varying from the Big Bang to the present, making the universe finely tuned only now but not earlier or later in its history. The physicists John Barrow and John Webb call these numbers the “inconstant constants,” and they have demonstrated how in particular the speed of light, gravitation, and the mass of the electron have in fact been inconstant over time.²⁰

2. Grand Unified Theory

In order to explain our universe we need a comprehensive theory of physics that connects the subatomic world described by quantum mechanics to the cosmic world described by general relativity. As the cosmologist Sean Carroll notes in his book From Eternity to Here: “Possibly general relativity is not the correct theory of gravity, at least in the context of the extremely early universe. Most physicists suspect that a quantum theory of gravity, reconciling the framework of quantum mechanics with Einstein’s ideas about curved spacetime, will ultimately be required to make sense of what happens at the very earliest times. So if someone asks you what really happened at the moment of the purported Big Bang, the only honest answer would be: ‘I don’t know.’”²¹That grand unified theory of everything will itself need an explanation, but it may be explicable by some other theory we have yet to comprehend out of our sheer ignorance at this moment in history. And as I repeat ad nauseum to audiences curious about unsolved mysteries and anxious to fill in scientific gaps with questionable pseudoscientific conjectures, it’s always okay to say “I don’t know” and leave it at that.

3. Boom-and-Bust Cycles

Perhaps our bubble universe is just one episode of an eternal boom-and-bust cycle of expansion and contractions of the universe, with the bubble’s eventual collapse and re-expansion in an eternal cycle. Sean Carroll argues that “space and time did exist before the Big Bang; what we call the Bang is a kind of transition from one phase to another.” As such, he says, “there is no such thing as an initial state, because time is eternal. In this case, we are imagining that the Big Bang isn’t the beginning of the entire universe, although it’s obviously an important event in the history of our local region.”²² Although there does not appear to be enough matter in our universe to halt the expansion and bring it back into a big crunch that could launch it back into a new bubble out of another Big Bang, the relevant observation here is that something existed before the Big Bang, thereby obviating the need to invoke a supernatural creator.²³

4. Darwinian Universes

According to the cosmologist Lee Smolin, the evolution of the universe may include a Darwinian component in the form of a “natural selection” of differentially reproducing bubble universes. Like its biological counterpart, Smolin hypothesizes that there might be a selection from different “species” of universes, each containing different laws of nature. Universes like ours will have lots of stars, which means they will have lots of black holes that collapse into singularities, a point at which infinitely strong gravity causes matter to have infinite density and zero volume, which many cosmologists believe gave birth to our universe from the Big Bang singularity. Perhaps collapsing black holes create new baby universes out of these singularities, and those baby universes with laws of nature similar to ours will be fine-tuned to life, whereas universes with radically different laws of nature that disallow stars, planets, and people will go extinct. The result of this cosmic evolutionary process would be a preponderance of universes like ours, so we should not be surprised to find ourselves in a universe fine-tuned for life.²⁴

5. Multiple Creations Cosmology

In his 1997 book The Inflationary Universe, the cosmologist Alan Guth proposes that our universe sprang into existence from a bubble nucleation of spacetime. If this process of universe creation is natural, then there may be multiple bubble nucleations that give rise to many universes that expand but remain separate from one another without any causal contact between them. Of course, if these universes were truly causally-disconnected then there is no way to get information from them, which would make this an untestable hypothesis.²⁵ But, again, there is much we still don’t know about the cosmos, and I am encouraged by the startling discovery of gravitational waves, which could open up possibilities of obtaining information from other bubble universes, if they exist.

6. Many-Worlds Multiverse

According to the “many worlds” interpretation of quantum mechanics, there are an infinite number of universes in which every possible outcome of every possible choice that has ever been available, or will be available, has happened in one of those universes. This model is grounded in the bizarre findings of the famous “double-slit” experiment, in which light is passed through two slits and forms an interference pattern of waves on a black surface (like throwing two stones in a pond and watching the concentric wave patterns interact, with crests and troughs adding and subtracting from one another). The spooky part comes when you send single photons of light one at a time through the two slits—they still form an interference wave pattern even though they are not interacting with other photons. How can this be? One answer is that the photons are interacting with photons in other universes! In this type of multiverse you could meet your doppelgänger, and depending on which universe you entered, your parallel self would be fairly similar or dissimilar to you, a theme that has become a staple of science fiction (see, for example, Michael Crichton’s Timeline). I am skeptical that this version of the multiverse will pan out, however, because the idea of there being multiple versions of me and you out there—and in an infinite universe there would be an infinite number of me’s and you’s—seems to me to be even less likely than the theistic alternative “God did it.” Still, as Richard Feynman famously quipped, “no one understands quantum mechanics,”²⁶ so who am I to write off this theory considered legitimate by many quantum physicists.

7. Brane and String Universes

Universes may be birthed when three-dimensional “branes” (a membrane-like structure on which our universe exists) moves through higher-dimensional space and collides with another brane, the result of which is the energized creation of another universe.²⁷ A related multiverse is derived through string theory, which by at least one calculation allows for 10⁵⁰⁰ possible worlds, all with different self-consistent laws and constants.²⁸ That’s a 1 followed by 500 zeroes possible universes. The number is so large that it would be miraculous if there were not intelligent life in a number of them. In his book God: The Failed Hypothesis, the late physicist Victor Stenger created a computer model that analyzes what just 100 different universes would be like under constants different from our own, ranging from five orders of magnitude above to five orders of magnitude below their values in our universe. Stenger found that long-lived stars of at least one billion years—necessary for the production of life-giving heavy elements—would emerge within a wide range of parameters in at least half of the universes in his model.²⁹

8. Quantum Foam Universe Creations

In this model, universes are created out of nothing, but in the scientific version of ex nihilo the nothing of the vacuum of space actually contains quantum foam, which may fluctuate to create baby universes. In this configuration, any quantum object in any quantum state may generate a new universe, each one of which represents every possible state of every possible object.³⁰ This is Stephen Hawking’s explanation for the fine-tuning problem that he himself famously presented in the 1990s:

Why is the universe so close to the dividing line between collapsing again and expanding indefinitely? In order to be as close as we are now, the rate of expansion early on had to be chosen fantastically accurately. If the rate of expansion one second after the Big Bang had been less by one part in 10¹⁰, the universe would have collapsed after a few million years. If it had been greater by one part in 10¹⁰, the universe would have been essentially empty after a few million years. In neither case would it have lasted long enough for life to develop. Thus one either has to appeal to the anthropic principle or find some physical explanation of why the universe is the way it is.³¹

Hawking’s collaborator Roger Penrose layered on even more mystery when he noted that the “extraordinary degree of precision (or ‘fine tuning’) that seems to be required for the Big Bang of the nature that we appear to observe…is one part in 10¹⁰¹²³at least.” Penrose suggested two pathways to an answer, either it was an act of God, “or we might seek some scientific/ mathematical theory.”³² Hawking opted for the second with this explanation: “Quantum fluctuations lead to the spontaneous creation of tiny universes, out of nothing. Most of the universes collapse to nothing, but a few that reach a critical size, will expand in an inflationary manner, and will form galaxies and stars, and maybe beings like us.”³³

9. M-Theory Grand Design, or Auto-Ex-Nihilo

Stephen Hawking continued working on this question, and he and the physicist Leonard Mlodinow presented their answer in their 2010 book The Grand Design.³⁴ They approach the problem from what they call “model-dependent realism,” based on the assumption that our brains form models of the world from sensory input, that we use the model most successful at explaining events, and that when more than one model makes accurate predictions “we are free to use whichever model is most convenient.” Employing this method, they write, “it is pointless to ask whether a model is real, only whether it agrees with observation.” The dual wave/particle models of light are an example of model-dependent realism, where each one agrees with certain observations but neither one is sufficient to explain all observations. To model the entire universe, Hawking and Mlodinow employ “M-Theory,” an extension of string theory that includes 11 dimensions and incorporates all five current string theory models. “M-theory is the most general supersymmetric theory of gravity,” Hawking and Mlodinow explain. “For these reasons M-theory is the only candidate for a complete theory of the universe. If it is finite—and this has yet to be proved—it will be a model of a universe that creates itself.” Although they admit that the theory has yet to be confirmed by observation, if it is then no creator explanation is necessary because the universe creates itself. Call it auto-ex-nihilo.

This article appeared in Skeptic magazine 23.1 Buy print edition Buy digital edition Subscribe to print edition Subscribe to digital edition

A SENSE OF AWE

By no means does this list exhaust the possible explanations for why there is something rather than nothing and why our universe is the way it is, but perhaps it gives one a sense that the questions are answerable through science, through natural and testable hypotheses and theories, without resort to supernatural intercession. It is good to reflect on the fact that the history of science is relatively young compared to the history of religion—roughly 500 v. 5000 years—so it is premature to say that because science does not yet have a definitive explanatory theory accepted by most scientists it means that one is not forthcoming. Despite the optimism derived from my expanding sphere of knowledge metaphor in which the known expands into the unknown at a ratio of 3:2, there is still much we do not understand about the cosmos and everything in it. But given science’s track record over the past five centuries this only means there are remarkable and exciting new discoveries and theories yet to come. As Carl Sagan expressed it in his 1985 Gifford Lecture Series titled The Search for Who We Are (published in book form posthumously in 2007 as The Varieties of Scientific Experience):

By far the best way I know to engage the religious sensibility, the sense of awe, is to look up on a clear night. I believe that it is very difficult to know who we are until we understand where and when we are. I think everyone in every culture has felt a sense of awe and wonder looking at the sky. This is reflected throughout the world in both science and religion.³⁵

About the Author

Dr. Michael Shermer is the publisher of Skeptic magazine, a monthly columnist for Scientific American and a presidential fellow at Chapman University. His latest book is Heavens on Earth: The Scientific Search for the Afterlife, Immortality, and Utopia.

References

1. Hawking, Stephen. 1988. A Brief History of Time. New York: Bantam Books, 190.
2. Rees, Martin. 2000. Just Six Numbers: The Deep Forces That Shape the Universe. New York: Basic Books.
3. Barrow, John D. and Frank Tipler. 1988. The Anthropic Cosmological Principle. Oxford: Oxford University Press, p. vii.
4. Leslie, John and Robert Lawrence Kuhn. 2013. The Mystery of Existence: Why is There Anything at All? Wiley- Blackwell. See also: Holt, Jim. 2012. Why Does the World Exist: An Existential Detective Story. New York: Liveright.
5. Kuhn, Robert Lawrence. 2007. “Why This Universe?: Toward a Taxonomy of Possible Explanations.” Skeptic, Vol.13, No.2, 28–39.
6. Ibid.
7. Kuhn, Robert Lawrence. 2013. “Levels of Nothing: There Are Multiple Answers to the Question of Why the Universe Exists.” Skeptic, Vol. 18, No. 2. http://bit.ly/1S7Mn9i
8. Vilenkin, Alex. 2006. Many Worlds in One: The Search for Other Universes. New York: Hill and Wang.
9. O’Connor, Timothy. 2008. Theism and Ultimate Explanation: The Necessary Shape of Contingency. Oxford: Blackwell.
10. Hume, David. 1776. Dialogues Concerning Natural Religion. Available online, p. 92: http://bit.ly/1sIsq4p
11. See also the clever take-down of the Ontological Argument in: Dawkins, Richard. 2006. The God Delusion. New York: Houghton Mifflin, 109–112.
12. Alleyne, Richard. 2009. “God is not the Creator, Claims Academic.” The Telegraph, October 8.
13. Callahan, Tim. 2012. “The Genesis Creation Myth is Not Unique.” eSkeptic, April 25. http://bit.ly/1UlVqbi
14. Carroll, Sean. 2016. The Big Picture: On the Origins of Life, Meaning, and the Universe Itself. New York: Dutton, 148.
15. Shermer, Michael. 2006. “Wronger Than Wrong.” Scientific American. November, 40.
16. Carroll, 2016, 149–150.
17. Stenger, Victor. 2008. God: The Failed Hypothesis. Buffalo: Prometheus Books.
18. Krauss, Lawrence. 2012. A Universe From Nothing: Why There is Something Rather Than Nothing. New York: Free Press, 169–170.
19. Krauss, Lawrence. 2017. The Greatest Story Ever Told—So Far: Why Are We Here? New York: Atria Books.
20. Barrow, John and John Webb. 2005. “Inconstant Constants.” Scientific American, June, 57–63.
21. Carroll, Sean. 2010. From Eternity to Here. The Quest for the Ultimate Theory of Time. New York: Dutton/Penguin, 50.
22. Carroll, op cit., 51, 64.
23. Steinhardt, Paul J. and Neil Turok. 2002. “A Cyclic Model of the Universe.” Science, May 2002: Vol. 296. no. 5572, pp. 1436–1439.
24. Smolin, Lee. 1997. The Life of the Cosmos. Oxford: Oxford University Press. See also: Smith, Quentin. 1990. “A Natural Explanation of the Existence and Laws of Our Universe.” Australasian Journal of Philosophy, 68, 22–43. For an elegant summary see: Gardner, James. 2003. Biocosm. Maui, HI: Inner Ocean Publishing.
25. Guth, Alan. 1981. “The Inflationary Universe: A Possible Solution to the Horizon and Flatness Problems.” Phys. Rev. D 23, 347; Guth, Alan. 1997. The Inflationary Universe: The Quest for a New Theory of Cosmic Origins. Boston: Addison-Wesley; Linde, Andrei. 1991. “The Self- Reproducing Inflationary Universe.” Scientific American, November 1991, 48–55. Linde, Andrei. 2005. “Current understanding of inflation.” New Astron. Rev. 49:35–41; Vilenkin, Alex. 2006. Many Worlds in One: The Search for Other Universes. New York: Hill and Wang.
26. Feynman, Richard. 1967. The Character of Physical Law. Cambridge, MA: MIT Press, 129.
27. Khoury, Justin, Burt A. Ovrut, Paul J. Steinhardt and Neil Turok. 2002. “Density Perturbations in the Ekpyrotic Scenario.” Phys. Rev. D66 046005; Ostriker, Jeremiah P. and Paul Steinhardt, “The Quintessential Universe.” Scientific American, January 2001, 46–53.
28. Bousso, Raphael and Joseph Polchinski. 2004. “The String Theory Landscape.” Scientific American, September.
29. Stenger, Victor. 2007. God: The Failed Hypothesis. Buffalo: Prometheus.
30. Everett, Hugh. 1957. “Relative State’ Formulation of Quantum Mechanics.” Reviews of Modern Physics 29, No.3, 1957, 454–462. Reprinted in DeWitt. B.S. and N. Graham, eds. 1973. The Many-Worlds Interpretation of Quantum Mechanics. Princeton NJ: Princeton University Press, 141–149. Wheeler, John Archibald. 1998. Geons, Black Holes & Quantum Foam. New York: W.W. Norton, 268–270.
31. Hawking, Stephen. 1996. “Quantum Cosmology.” In Hawking, Stephen and Roger Penrose. The Nature of Space and Time. Princeton, NJ: Princeton University Press, pp. 89–90.
32. Penrose, Roger. 2005. The Road to Reality: A Complete Guide to the Laws of the Universe. New York: Knopf, p. 726–732, 762–765.
33. Hawking, Stephen. 2002. “The Future of Theoretical Physics and Cosmology: Stephen Hawking 60th Birthday Symposium,” Lecture at the Centre for Mathematical Sciences, Cambridge, UK, 11 January.
34. Hawking, Stephen and Leonard Mlodinow. 2010. The Grand Design. New York: Bantam Books.
35. Sagan, Carl. 2007. The Varieties of Scientific Experience.

What Came Before the Big Bang?

Cosmologist Alexander Vilenkin has convincing evidence that we are surrounded by expanding, bubble-like universes. | Roen Kelly (Illustration); Mark Ostow (Photo)

What Came Before the Big Bang?

by Steve Nadis|Thursday, October 10, 2013

From the September 2013 Issue

Cosmologist Alexander Vilenkin believes the Big Bang wasn't a one-off event, but merely one of a series of big bangs creating an endless number of bubble universes.

It is cosmology’s most fundamental question: How did the universe begin?

The question presupposes that the universe had an actual starting point, but one might just as well assume the universe always was and always will be. In that case, there would be no beginning whatsoever — just an ever-evolving story of which we’re catching a mere glimpse.

“We have very good evidence that there was a Big Bang, so the universe as we know it almost certainly started some 14 billion years ago. But was that the absolute beginning, or was there something before it?” asks Alexander Vilenkin, a cosmologist at Tufts University near Boston. It seems like the kind of question that can never be truly answered because every time someone proposes a solution, someone else can keep asking the annoying question: What happened before that?

But now Vilenkin says he has convincing evidence in hand: The universe had a distinct beginning — though he can’t pinpoint the time. After 35 years of looking backward, he says, he’s found that before our universe there was nothing, nothing at all, not even time itself.

Throughout his career, including the 20-plus years he has directed the Tufts Institute of Cosmology, Vilenkin has issued a series of wild, dazzling ideas, though from the outside he looks neither wild nor dazzling. The 64-year-old professor is soft-spoken, trim and of modest build. He dresses neatly, in neutral, understated tones that don’t draw attention to him.

Despite a low-key manner bordering on subdued, Vilenkin is a creative force who has continually found ways of piercing the fog surrounding some of the densest quandaries imaginable — triumphs that have earned him the respect of scholars worldwide. “Alex is a very original and deep thinker who has made important and profound contributions to our notions about the creation of the universe,” says Stanford cosmologist Andrei Linde.

Yet this brilliant career might never have happened. Born in the Soviet Union in 1949 and raised in the Ukrainian city of Kharkiv, Vilenkin got hooked on cosmology in high school, after reading about the Big Bang in a book by Sir Arthur Eddington. That “obsession” over the universe’s origins, Vilenkin says, “has never left me. I felt that if you could work on this question, which may be the most intriguing one of all, why would you choose to work on anything else?”

As an undergraduate at Kharkiv National University, Vilenkin says he was advised to “do some real physics” rather than pursue his first love, cosmology. Although he was an excellent student, he could not get into any graduate programs in physics because, he suspects, the KGB blacklisted him for refusing to become a government informant. Instead, Vilenkin was forced to take a series of mundane jobs. For a while he taught night school for adults but left that position because his responsibilities included going to the homes of absentees, many of whom were alcoholics, to try and drag them to school — an unenviable task. 

He was a night watchman for about a year and a half, including a stint at the Kharkiv Zoo. To protect the animals (which were sometimes hunted for food), he was given a rifle that he didn’t know how to use and fortunately never had to fire. When he had time during those long nights, Vilenkin studied physics, an avocation that included reading the four-volume collected works of Albert Einstein. He got fired from this plum assignment when someone decided — perhaps based on his choice of reading material — that he was overqualified for the task at hand. 

With his employment prospects looking bleak, he decided to emigrate to the United States; he figured he’d start out washing dishes while trying to break into academia. But getting out of the Soviet Union required an elaborate plan: Jews like him were allowed to go to Israel in small numbers, determined by a quota, but one had to secure an invitation from Israeli relatives first. Vilenkin had no actual relatives there, so he contacted a friend who knew people in Israel and eventually found someone — a stranger to him — kind enough to write a letter on his behalf. 

After the letter arrived, he waited a year for a visa, but it came at great cost. Before Vilenkin and his wife could leave, their parents had to consent to the move. For giving their permission, his wife’s parents lost their laboratory jobs. His father, a university professor, later lost his job, too. The traditional stop en route to Israel was Vienna, but from there Vilenkin, his wife and 1-year-old daughter went to Rome instead, arriving in 1976. They met with the U.S. Consulate in Rome and, after a three-month wait, were finally granted a visa to the U.S.

Back to the Big Bang

In fall 1977, Vilenkin took a postdoctoral position at Case Western Reserve, where he was supposed to study the electrical properties of heated metals. Still, he found time on the side to theorize about spinning black holes and their mysterious magnetic fields. A year later, he got his lucky break when Tufts offered him a one-year visiting position. He took a gamble by poring himself into cosmology, an area considered fringe at the time. 

That would soon change. In late 1979, a Stanford physics postdoc named Alan Guth offered an explanation for the explosive force behind the Big Bang. Guth’s intellectual leap stemmed from theories in particle physics, which held that at extremely high energies — far higher than could ever be reached in a laboratory — a special state of matter would turn gravity upside down, rendering it a repulsiverather than an attractive force. 

A patch of space containing a tiny bit of this unusual matter could repel itself so violently as to literally blow up. Guth suggested that a tremendous burst of this sort triggered the Big Bang, swiftly enlarging the universe so much it doubled in size at least 100 times. This exponential growth spurt — called cosmic inflation — was short-lived, however, lasting just a tiny fraction of a second because the repulsive material quickly decayed, leaving behind the more familiar forms of matter and energy that fill the universe today.

The idea simultaneously solved a number of puzzles in cosmology. It explained where the “bang” behind the Big Bang came from and how the cosmos got so big. Rapid inflation in every direction also explained why the universe we now observe is so homogeneous, and why the temperature of the background radiation left over from that primordial blast is uniform, in every patch of the sky, to one part in 100,000. Inflation also revitalized cosmology, giving theorists like Vilenkin plenty to think about — and a bit more respectability to boot.

The Never-Ending Story

By 1982, a couple of years after Guth’s breakthrough, Vilenkin had a realization of his own: The process of inflation had to be eternal, meaning that once it started, it never fully stopped. Inflation might end abruptly in one region of space, such as the one we inhabit, but it would continue elsewhere, setting off a never-ending series of big bangs. Each bang would correspond to the birth of a separate “pocket” universe, which might be pictured as an expanding bubble — one of countless bubbles floating around within the “multiverse,” as it’s sometimes called.

As Vilenkin saw it, inflation’s eternal nature stemmed from two competing properties of the cosmic fuel, the gravity-repulsive material that caused the universe to rapidly expand. On the one hand, the material was unstable, much like radioactive substances, and was thus doomed to decay. On the other hand, the material expanded far faster than it decayed, so even though decay might stop inflation in certain regions, runaway growth would continue in others.

As an analogy, Vilenkin suggests a blob of bacteria that wants to keep reproducing and growing, while bacteria-killing antibodies try to curtail that growth. If the bacteria reproduce much faster than they’re destroyed, they will swiftly multiply and spread even though their reproduction may be thwarted in some quarters. Either way you look at it, the net result is that inflation (or bacterial growth) never ends everywhere at once and is always going on in some portion of the multiverse — even as you read this magazine.

To gain a better sense of the phenomenon, Vilenkin teamed up in 1986 with a Tufts graduate student, Mukunda Aryal, on a computer simulation that showed what an eternally inflating universe might look like. In their simulation, inflating regions, or bubbles, started small and steadily grew, while the space between bubbles stretched out as well. Each bubble — representing a mini-universe like ours — was surrounded by smaller bubbles, which were themselves surrounded by even smaller bubble universes, in turn.

Road to Eternity

In Vilenkin’s bubbling universe, inflation was, by definition, eternal into the future. Once initiated, it would not stop. But was it also eternal into the past? Was there ever a time when the universe was not inflating? And if the universe were always inflating, and always expanding, would that imply that the universe itself was eternal and had no beginning?

To address this question, Vilenkin joined forces with Guth and Long Island University mathematician Arvind Borde. Using a mathematical proof, they argued that any expanding universe like ours had to have a beginning. The thought experiment they posed went like this: Imagine a universe filled with particles. As it steadily expands, the distance between particles grows. It follows that observers sprinkled throughout this expanding universe would be moving away from each other until, eventually, they occupied widely scattered regions of space. If you happened to be one of those observers, the farther an object was from you, the faster it would be moving away. 

Now throw into the mix a space traveler moving through space at a fixed speed: He zooms past Earth at 100,000 kilometers per second. But when he reaches the next galaxy, which is moving away from us at, say, 20,000 kilometers per second, he will appear to be moving only 80,000 kilometers per second to observers there. As he continues on his outward journey, the space traveler’s speed will appear smaller and smaller to the observers he passes. Now we’ll run the movie backward. This time, the space traveler’s velocity will appear faster and faster at each successive galaxy.

If we assume inflation is eternal into the past — that it had no beginning — the space traveler will eventually reach and overtake the speed of light. A calculation by Borde, Guth and Vilenkin showed that this would happen in a finite amount of time. But according to the laws of relativity, it is impossible for any massive object to reach the speed of light, let alone exceed it. “This cannot happen,” says Vilenkin. “So when you follow this space traveler’s history back in time, you find that his history must come to an end.” 

The fact that the traveler’s journey backward in time hits an impasse means that there’s a problem, from a logical standpoint, with the assumption of an ever-expanding universe upon which this whole scenario is based. The universe, in other words, could not always have been expanding. Its expansion must have had a beginning, and inflation — a particularly explosive form of cosmic expansion — must have had a beginning, too. By this logic, our universe also had a beginning since it was spawned by an inflationary process that is eternal into the future but not the past. 

Something From Nothing

A universe with a beginning begs the vexing question: Just how did it begin? Vilenkin’s answer is by no means confirmed, and perhaps never can be, but it’s still the best solution he’s heard so far: Maybe our fantastic, glorious universe spontaneously arose from nothing at all. This heretical statement clashes with common sense, which admittedly fails us when talking about the birth of the universe, an event thought to occur at unfathomably high energies. It also flies in the face of the Roman philosopher Lucretius, who argued more than 2,000 years ago that “nothing can be created from nothing.” 

Of course, Lucretius had never heard of quantum mechanics and inflationary cosmology, 20th-century fields that contest his bold claim. “We usually say that nothing can be created out of nothing because we think it would violate the law of conservation of energy,” a hallowed principle in physics holding that energy can neither be created nor destroyed, Vilenkin explains. So how could you create a universe with matter in it, where there had been nothing before?

“The way the universe gets around that problem is that gravitational energy is negative,” Vilenkin says. That’s a consequence of the fact, mathematically proven, that the energy of a closed universe is zero: The energy of matter is positive, the energy of gravitation is negative, and they always add up to zero. “Therefore, creating a closed universe out of nothing does not violate any conservation laws.” 

Vilenkin’s calculations show that a universe created from nothing is likely to be tiny, indeed — far, far smaller than, say, a proton. Should this minute realm contain just a smattering of repulsive-gravity material, that’s enough to ensure it will ignite the unstoppable process of eternal inflation, leading to the universe we inhabit today. If the theory holds, we owe our existence to the humblest of origins: nothing itself.

One virtue of this picture, if correct, is that the spontaneous creation of our universe gives a definite starting point to things. Time begins at the moment of creation, putting to rest the potentially endless questions about “what happened before that.” 

Yet the explanation still leaves a huge mystery unaddressed. Although a universe, in Vilenkin’s scheme, can come from nothing in the sense of there being no space, time or matter, something is in place beforehand — namely the laws of physics. Those laws govern the something-from-nothing moment of creation that gives rise to our universe, and they also govern eternal inflation, which takes over in the first nanosecond of time.

That raises some uncomfortable questions: Where did the laws of physics reside before there was a universe to which they could be applied? Do they exist independently of space or time? “It’s a great mystery as to where the laws of physics came from. We don’t even know how to approach it,” Vilenkin admits. “But before inflation came along, we didn’t even know how to approach the questions that inflation later solved. So who knows, maybe we’ll pass this barrier as well.”

In the Clint Eastwood movie Magnum Force, Harry Callahan says, “A man’s got to know his limitations,” but Vilenkin’s work is a testament to pushing past traditional limits. If we persevere in the face of skepticism and doubt, as Vilenkin is often inclined to do, interesting and unexpected ideas may well emerge — just like a universe popping out of nowhere.

Eliminating the Loopholes

Loophole #1

To bolster his hypothesis, Vilenkin has studied other model universes, eliminating loopholes that contradict the idea of a clear-cut cosmic debut. In a 2012 paper with Tufts graduate student Audrey Mithani, Vilenkin examined the “cyclic” universe investigated by physicists Paul Steinhardt of Princeton University and Neil Turok, now at the Perimeter Institute.

In this model, there is neither a single Big Bang nor a single beginning. Instead, the universe continually goes through oscillating cycles of expansion, contraction, collapse and expansion anew. The catch is that the cyclic universe runs into the second law of thermodynamics, which says the entropy, or disorder, of a closed system will inevitably increase over time. 

For example, an ornate brick mansion is highly ordered, whereas a pile of bricks strewn across the ground — the result of the ravages of nature and decades or centuries of neglect — is more disordered. And brick dust, scattered by wind and water after the bricks themselves have deteriorated, is even more disordered. Left on its own, a system — even a bubble universe — will naturally go this way. We don’t often see a brick mansion spontaneously reassembling itself from dispersed dust. 

If our universe has been here forever and maintained a stable size, it, too, would have succumbed to the second law. Disorder would have inexorably increased to the point that the universe would now be a smoothed-out, featureless blur. But that’s not what we see at all. Instead, we see a universe filled with grand cosmic structures — galaxies, clusters of galaxies, clusters of clusters called superclusters, and clusters of superclusters called galaxy filaments — some of the latter stretching a billion or more light-years across.

For that reason, Vilenkin rules out the cyclic universe picture unless one makes the added assumption that after each cycle of expansion and contraction, the universe ends up somewhat bigger than when it started. The stipulation would leave us with another expanding universe, meaning that the original Borde-Guth-Vilenkin theorem would still apply: An ever-expanding universe must have a single beginning.

Loophole #2

Another possible loophole is the “cosmic egg” scenario, a model universe advanced by South African cosmologist George Ellis, among others. According to this view, the universe can sit forever in a stable configuration, with a fixed size and radius, until it suddenly starts to expand — like an egg hatching after an exceptionally long incubation phase. 

The trouble with this proposition, according to Vilenkin and Mithani, is that the small “stable” universe is not so stable after all. Sometime during the long waiting phase it would collapse to nothingness, before it ever reached the expansionist period — that is, if the laws of quantum mechanics are to be believed. 

Quantum mechanics, the prevailing branch of physics for describing how things work on atomic scales, is exquisitely well-tested, and exquisitely weird. Quantum mechanics holds that if there is even the tiniest chance of something happening, however absurd it may sound, that thing is sure to happen if you wait long enough. 

As it turns out, quantum mechanical formulas predict a slim (but nonzero) chance of the cosmic egg universe collapsing to zero size, at which point the erstwhile universe would completely disappear. Given an infinite time span, which is what the cosmic egg scenario calls for, such a collapse would be unavoidable — even though the odds of it occurring at any one time are small — implying that the universe could not have existed forever.

Indeed, says Vilenkin, among all the ideas we’ve thought of so far for a universe without a beginning, none of them seem to work. “So the answer to the question of whether the universe had a beginning is yes, it probably did.”

[This article originally appeared in print as "Starting Point."]