Victor J. Stenger has created new universes. Lots of them. In some, the stars shine for only a fraction of a second. In others, atoms are the size of tennis balls and a typical day lasts trillions of hours. Stenger achieves these wildly disparate results by altering a few of the underlying "constants" of nature–the mass of a proton, for example, or the strength of the electromagnetic force. He ends up with worlds that look radically different from our own.
Stenger is a theoretical physicist at the University of Hawaii and author of a book titled The Unconscious Quantum: Metaphysics in Modern Physics and Cosmology. His "universes" are computer simulations, the output of a program that he wrote and has named–a bit provocatively–"Monkey God." Stenger does not plan out the universes that he creates; he has allowed particle masses and force strengths to vary randomly, many orders of magnitude different from the levels observed in nature. A lot of the resulting universes, says Stenger, "look pretty funny but still had long-lived stars."
The behavior of stars and atoms in imaginary universes might seem like a topic unlikely to interest anyone who is not a theoretical physicist. Yet Stenger's calculations pertain to an issue that was initially raised by physicists but has lately echoed far beyond the scientific community–even spilling onto the covers of popular magazines and into the world of politics. The issue is an apparent "fine-tuning" of the laws of physics, a set of circumstances without which humans would not exist. And Stenger, with his computer universes, is trying to inject a note of reality into a public discussion that has run far afield of the relevant science.
A Custom-Made Universe
"Science Finds God," trumpeted a Newsweek cover story in July 1998. The article, by journalist Sharon Begley, ranges broadly across modern physics, finding various possible links to theology. Some of these links seem little more than metaphorical; for example, electrons behave simultaneously like waves and particles, and (perhaps similarly) Jesus is understood by Christians to be both human and divine. But Begley also cites what seems like real evidence of divine action: "Physicists have stumbled on signs that the cosmos is custom-made for life and consciousness. It turns out that if the constants of nature–unchanging numbers like the strength of gravity, the charge of an electron and the mass of a proton–were the tiniest bit different, then atoms would not hold together, stars would not burn and life would never have made an appearance."
"Science Sees the Light," announced The New Republic last October. This cover story, by journalist Gregg Easterbrook (and adapted from his book Beside Still Waters: Searching for Meaning in an Age of Doubt), also raises the fine-tuning question. Easterbrook writes: "Researchers have calculated that, if the ratio of matter and energy to the volume of space, a value called 'omega,' had not been within about one-quadrillionth of one percent of ideal at the moment of the Big Bang, the incipient universe would have collapsed back on itself or suffered runaway relativity effects. Instead, our firmament is stable and geometrically normal: 'smooth,' in the argot of cosmology postdocs."
George F. Will seems to be impressed. Citing Easterbrook's book, Will writes in his Newsweek column that the "news from the cosmos" is "staggeringly implausible" and therefore "theologically suggestive." Humanity owes its existence, Will notes, to the delicate balancing of forces in the early universe: "The odds against us were–this is just the right word–astronomical." The conservative columnist muses that soon "the American Civil Liberties Union, People for the American Way, or some similar faction of litigious secularism will file suit against NASA, charging that the Hubble Space Telescope unconstitutionally gives comfort to the religiously inclined."
Easterbrook's article, despite its bold headline, is hedged with uncertainties; he notes that the value of omega and other seemingly improbable features of the universe might yet lend themselves to a naturalistic explanation. A different tone is set by Patrick Glynn, whose 1997 book God: The Evidence asserts that recent scientific developments constitute a "powerful-indeed, all-but-incontestable case for what once was considered a completely debatable matter of 'faith': the existence of soul, afterlife, and God." Glynn, who served as an arms control expert in the Reagan administration, writes frequently for National Review and other conservative magazines.
Glynn's argument incorporates psychological and medical issues (including reports of "near-death experiences"). But much of his book is about physics. Glynn writes that physicists have discovered "an increasingly daunting and improbable list of mysterious coincidences or 'lucky accidents' in the universe–whose only common denominator seemed to be that they were necessary for our emergence." Even "minor tinkering" with the strength of gravity and other forces, or with the masses of subatomic particles, writes Glynn, "would have resulted in an unrecognizable universe: a universe consisting entirely of helium, a universe without protons or atoms, a universe without stars, or a universe that collapsed back in upon itself before the first moments of its existence were up."
According to Glynn, this all amounts to a momentous scientific discovery, one that goes by the name "the anthropic principle." This term was introduced by cosmologist Brandon Carter at a conference in 1973, but according to Glynn, Carter presented the idea "in an unfortunately technical and roundabout way," such that its full implications were slow to be recognized. What is the anthropic principle? "In essence," Glynn writes, the principle "came down to the observation that all the myriad laws of physics were fine-tuned from the very beginning of the universe for the creation of man–that the universe we inhabit appeared to be expressly designed for the emergence of human beings."
God: The Evidence, which was recently reissued in paperback, has received favorable reviews in the conservative press. Moreover, Glynn's exposition of the anthropic principle has been greeted with enthusiasm in conservative intellectual circles, where arguments for natural "design" were previously limited to critiques of evolutionary biology. In The Wall Street Journal, editorial page assistant editor Melanie Kirkpatrick writes approvingly that Glynn's "thesis is that the scientific discoveries of the past 25 years, especially in the physical sciences, have refuted the idea of a 'random universe'–the modern idea that human life was a chance event–in favor of the 'anthromorphic [sic] principle': the idea that there is an intelligent guiding hand at work." Similar compliments were published in The Washington Times, Insight, and National Review.
Robert Bork, whose favorable blurb adorns the dust jacket of God: The Evidence, takes note of Glynn's argument (expressed in an earlier National Review piece) in his own book Slouching Towards Gomorrah. Bork writes that "the argument from design is now bolstered by the findings of physics concerning the Big Bang. We now know that there were a great many 'coincidences' at the outset of the universe that were essential if life was to exist." These "findings," coupled with arguments for creationism in biology, provide Bork with a ray of hope in his otherwise grim assessment of current intellectual trends. "Religion," he asserts, "will no longer have to fight scientific atheism with unsupported faith."
Glynn, for his part, is positively exultant. He explains, in a March 1998 interview with Insight, that "the anthropic principle is a major turning point in Western intellectual history–a major, major turning point–because it really marks the end of the modern period when mechanism was triumphant, when the view of the universe as matter and motion was triumphant. The anthropic principle undercuts that completely." He adds: "The anthropic principle puts the antitheists, the people who are arguing against the existence of God, in a very tough spot."
To evaluate such claims, it is necessary first to clarify some confusing terminology. The "anthropic principle" is a much-discussed concept among physicists. Most of this discussion, however, has nothing to do with intelligent design. This is because the "principle" has multiple definitions and shades of meaning. A crucial distinction is between the "strong anthropic principle" and the "weak anthropic principle." The "strong" version is an argument for design (or, in some variations, that the universe somehow "requires" that life exist). The "weak" version, by contrast, is generally what physicists mean when they discuss the anthropic principle.
The "weak" anthropic principle, simply stated, is that life does exist and the laws of physics allow this to occur. That might sound like an obvious point, but it can produce useful insights. In the 1950s, for example, astronomer Fred Hoyle predicted a particular "resonance," or energy level, for the nuclei of carbon atoms. Subsequent experiments proved him correct. How did Hoyle know? Because without such a resonance, stars would not produce much carbon–and life as we know it would not exist. (Of course, it does not necessarily follow that the carbon resonance was "designed" or "required" for that purpose.)
Moreover, the term anthropic may be misleading, as it implies that the laws of physics have some particular suitability for humans, as opposed to other species. But in fact, the "fine-tuning," such as it is, appears compatible with the entire range of life on Earth, past and present. Mathematician David A. Shotwell, commenting on Glynn's book in Skeptical Inquirer magazine, writes: "Perhaps the Creator, if there is one, really wanted to produce dinosaurs, and we [humans] are an unimportant byproduct of the enterprise. It might be objected that dinosaurs are, after all, extinct. That is true enough, but does anyone think that we will be here forever?"
Furthermore, if dinosaurs were not the objective, Shotwell points out, then it might be "insects, the most successful of all life forms. The total number of them is somewhere in the trillions, as compared with only a few billion humans." Shotwell therefore proposes an "entomologic principle," which states that the laws of physics were fine-tuned to produce insects. (The late astronomer Carl Sagan took this line of thinking even further, proposing a "lithic principle." The universe, Sagan observed, seems exquisitely fine-tuned to produce rocks.)
Leaving aside questions about what species may be favored, it may still seem remarkable that, as Newsweek puts it, "life would never have made an appearance" in a slightly different universe. But any such claim requires considerable assumptions about both life and the universe. That, in fact, is the point made by the University of Hawaii's Stenger and his "Monkey God" program. Stenger allowed the strengths of forces and the masses of particles in his "universes" to vary randomly across ten orders of magnitude (in other words, as much as 100,000 times more or 100,000 times less than their values in nature). The resulting "universes," in most cases, had stars lasting over a billion years–an apparently crucial prerequisite for the evolution of life.
To be sure, most of these propitious "universes" would be unlikely to produce humans, insects, or other carbon-based life forms such as exist on Earth. But they might well allow something to evolve. There is no good reason, says Stenger, to "assume that there's only one kind of life possible"–we know far too little about life in our own universe, let alone "other" universes, to reach such a conclusion. Stenger denounces as "carbon chauvinism" the assumption that life requires carbon; other chemical elements, such as silicon, can also form molecules of considerable complexity. Indeed, Stenger ventures, it is "molecular chauvinism" to assume that molecules are required at all; in a universe with different properties, atomic nuclei or other structures might assemble in totally unfamiliar ways.
But what about the fine-tuning of something called "omega," without which the universe would have, as Easterbrook puts it, "collapsed back on itself or suffered runaway relativity effects"? Isn't this, as George Will writes, "theologically suggestive"? Actually, this particular cosmic mystery may have already been solved, without recourse to theology. The answer lies in the theory of cosmic inflation, first developed by MIT physicist Alan Guth and now widely accepted among cosmologists. Inflation theory states that the early universe underwent a brief period of exponential growth before settling into the slower expansion seen since. And the relevant point here is that omega (which is a measure of the "curvature" of space) is not a constant; it changes with time.
Easterbrook writes that omega had to be "within about one-quadrillionth of one percent of ideal at the moment of the Big Bang." But actually, omega could have started out at just about any number, and it still would have hit the required "ideal." Why? Because this ideal is a very special number: one. If omega equals one, the universe is perfectly "flat" or "smooth" (whereas numbers higher or lower mean its geometry is warped by matter and energy). Now, think of a balloon; as it inflates, its surface becomes increasingly flat and smooth. And if the universe (or a balloon) is inflating exponentially–which is to say, extremely fast–then its geometry will get extremely flat very quickly, no matter how wrinkled it may have been before.
As Guth explains in his book The Inflationary Universe, "With inflation, it is no longer necessary to postulate that the universe began with a value of omega incredibly close to one. Before inflation, omega could have been 1,000 or 1,000,000, or 0.001 or 0.000001, or even some number further from one. As long as the exponential expansion continues for long enough, the value of omega will be driven to one with exquisite accuracy." Moreover, in the billions of years since, as stars and galaxies formed, the curvature of space likely has drifted from its "fine-tuned" value. (In case you're curious, current astronomical evidence indicates omega is somewhere between 0.1 and two.)
"Mathematics works. Religion doesn't," says Rocky Kolb, a cosmologist at the Fermi National Accelerator Laboratory in Illinois. Kolb is not denouncing religion. Rather, he is saying that the "strong" anthropic principle–the argument for design–merely cuts short further study of phenomena such as cosmic inflation. And the "weak" principle, he notes, is essentially a stopgap tool, not an explanation of anything. "If you just shrugged your shoulders and mumbled 'anthropic principle,' then science doesn't advance," says Kolb. "Sometimes, the alternative to the anthropic principle is work."
A Vast Froth of Bubbles
Why do the seeming "constants" of nature–the strengths of forces and the masses of particles–have the values that they have? It may be that they are not constants at all. Much current work in cosmology points to two remarkable, and interrelated, possibilities: What we regard as the universe may in fact be just one part of a far larger "multiverse." And the laws of physics may have "evolved" in a process similar to natural selection in biology. These ideas remain speculative, but they cast the "fine-tuning" issue in a whole new light-and they do so without invoking intelligent design.
According to theories of the multiverse, the Big Bang was not a unique event. Instead, numerous "big bangs" have occurred–and continue to do so, in regions beyond our observational horizon. Each "bang" leads to a new universe, one bubble in a vast froth of bubbles. (One might object that the "universe" by definition is everything that exists, but its expanded scope if such theories are correct has given rise to the "universe/multiverse" terminology.) Different universes contain different combinations of forces and particles. If the range of combinations that support life is narrow, then the multiverse might be littered with uninhabited bubbles. But in at least one universe, the "constants" are suitable for carbon-based life.
The latter may be just a matter of chance. Given enough universes, sooner or later one is likely to hit upon the "right" combination for life (even assuming only one type of life is possible). But there may be more to it than that. Consider the theory of "cosmological natural selection" proposed by Penn State physicist Lee Smolin and detailed in his 1997 book The Life of the Cosmos. In this theory, our universe emerged from a black hole in a previous universe; moreover, each black hole in our universe (and other universes) generates yet another universe. Universes that produce lots of black holes therefore have more "progeny" than universes that don't. The laws of physics are reshuffled slightly with each black hole, and increasingly the multiverse is dominated by universes whose laws are "fine-tuned" to produce black holes.
So what? Well, black holes are formed when massive stars collapse. Stars are massive if they contain heavy elements–elements such as carbon. The selection process thus gives rise to universes such as our own, where carbon and other heavy elements are available as the building material for life.
In God: The Evidence, Glynn dismisses all multiple-universe theories, including Smolin's. These, he argues, are contrivances produced by "secular-minded scientists" to explain away the evidence for design. Glynn writes that "some scientists have speculated that there may exist billions of `parallel' universes–which, mind you, we will never be able to detect–of which ours just happens to be one. If there were billions of invisible universes, then the series of miraculous coincidences that produced life in this one might not seem so unlikely." Such theories, according to Glynn, are "reminiscent of medieval theologians' speculations about the number of angels that could dance on the head of a pin."
But is the multiverse so far-fetched? The Big Bang seems to have occurred under conditions of extremely high density; similar conditions occur throughout our universe–in black holes. Similarly, Stanford cosmologist Andrei Linde argues that the fast inflation of the early cosmos–which requires merely a small region of curved space, or "false vacuum," to get started–implies a "self-reproducing" universe. The assumption that there are not multiple universes seems unwarranted by current evidence. Says Stenger: "There's no law of any kind that we know that says this could only have happened once. In fact, you'd have to invent a law of nature to explain why there was only one universe."
Moreover, while we may "never be able to detect" other universes, there are indirect ways to assess whether they exist. If Smolin's theory of cosmological natural selection is correct, then our universe should be "optimized" for black-hole production. This can be tested; for instance, a particle known as the kaon, which can be created in particle accelerators, should have a mass in the "correct" range to ensure that neutron stars eventually become black holes. So far, the theory has held up under such testing, but the evidence is inconclusive.
Perhaps surprisingly, however, Smolin is hoping that the theory as stated in his book is false. He's not particularly fond of its multiple universes. "I would be very, very happy if in the final picture we got rid of it," he says in an interview. "That it was just a kind of way station." A way station to what? To a similar theory in which the laws of physics undergo "natural selection" entirely within our universe. In such a theory, different regions of the early universe "compete for dominance," some expanding faster than others. That is what he is working on now, and he is trying to make it testable.
Politics By Design
Has physics found God? The evidence is, at best, highly ambiguous. Some of it points in an opposite direction–toward a universe that can appear marvelously fine-tuned even if there is no Fine Tuner. Certainly, not many physicists are prepared to announce that a cosmic plan has been unveiled. The few cosmologists who favor the "strong" anthropic principle usually defend it as plausible speculation, not established fact. (And even the "strong" principle has versions that seem unrelated to religion.)
How then did this arcane scientific discussion get converted into popular articles and books touting evidence of the divine? The answer no doubt lies partly in the exigencies of media sensationalism. Had Newsweek proclaimed on its cover "Science Still Not Sure About God," then newsstand sales would have slumped that week. Had The New Republic headlined its cover story "Science Sees a Blurry Picture That May Have Something to Do With God but Mainly Just Shows the Universe Is an Interesting Place," it would have lacked the pungency of "Science Sees the Light" (though it would have more accurately reflected Easterbrook's article).
But what about the conservatives who have embraced the "anthropic" design argument? They seem to have more serious priorities than merely titillating readers. Glynn points to "the mischievous consequences of atheistically inspired social policy and social experimentation." These consequences, in his telling, range from Soviet atrocities to America's sexual revolution, with its "explosion in teenage pregnancies" and "epidemic of sexually transmitted diseases." Now, however, "the anthropic principle" is replacing "the random universe," and the scientific basis for atheism is crumbling. Bork, for his part, welcomes evidence for design in nature because it lends support to religious belief, and "such belief is probably essential to a civilized future."
Clearly, these conservatives have found an interpretation of cosmology that is congruent with their political beliefs. Yet that doesn't mean the interpretation is presented insincerely. Ronald Bailey has speculated in REASON that conservative opponents of Darwinism might be following a tenet of philosopher Leo Strauss: that religious belief is unfounded but still required by society. (See "Origin of the Specious," July 1997.) But in God: The Evidence, Glynn denounces the Straussian position; moreover, he traces his own spiritual crisis and recovery of religious belief with considerable emotion. He clearly means what he says about both God and the anthropic principle.
Nor is there any reason to doubt the sincerity of Bork, Will, or other conservatives who have discovered evidence of design in the laws of physics. In many cases, however, there is plenty of reason to doubt their knowledge. Bork and Will make sweeping statements about the universe based on a cursory reading of popular accounts. The Wall Street Journal's and The Washington Times' reviewers of Glynn's book accept at face value his misleading definition of the anthropic principle. Glynn devotes four pages to a puerile analogy about monkeys with typewriters. (Yes, if the monkeys are assumed to be unchanging beings with limited capacities, they would never type Shakespeare. It does not follow that the universe is subject to similar constraints.)
It is hard to believe that the "anthropic" conservatives have contemplated the full implications of their position. There is, to begin with, a theological puzzle. Why would an omnipotent or highly powerful deity need to fine-tune physical laws? Such tinkering seems to set limits on what the Fine Tuner can do. Did this entity have no choice but to produce carbon-based life–or would other physical laws have generated other types of life? (If the latter, then the fine-tuning argument collapses.) If the laws of physics were not compatible with our type of life–and yet we were here–wouldn't that be evidence for God?
Moreover, if there is now evidence for God's existence, what happens if the evidence doesn't hold up under scrutiny? Religious faith need never be damaged by a scientific advance; one can always believe that a powerful deity intervenes in the universe while erasing all proof of such intervention. But evidence can be overturned or reinterpreted any time (as appears to have already happened with the "fine-tuning" of omega). Won't society be harmed if the strength of gravity or the mass of the proton turn out not to have the religious implications that conservatives have publicized?
Finally, what does the apparent fine-tuning in physics imply for biology? Glynn claims that the fossil record shows that "natural selection is not the magic bullet biologists once thought it was." Bork states that the complexity of organisms could not have evolved unaided. But if the cosmos is precisely fine-tuned for the development of life, then why is further tinkering required? The traditional argument for design is that nature is too inhospitable for life to have evolved. The "anthropic" design argument is that nature is eerily hospitable to life. If both are true, it's a strange universe indeed.