Searching for God at the Center of the Big Bang

What quantum mechanics can tell us about the possibility of life after death and resurrection. Peter Woit reviews “A Big Bang in a Little Room: The Quest to Create New Universes” by Zeeya Merali.

By Peter Woit

A model of multiple universes evolving after the Big Bang. Photo: Science Source

Human beings have always been fascinated by the question of the origin of the universe. The past hundred years have seen a dramatically successful effort by physicists and astronomers to move this question from untestable philosophical and theological speculation to solid science. We now have a relatively well-understood theory that allows us to trace the history of the universe back to some moments after a “Big Bang.” What happened at the Big Bang—or before—is an irresistible question but one that, for now, as science, lies in the realm of the purely speculative.

In “A Big Bang in a Little Room,” science writer Zeeya Merali turns the question around, asking instead whether physicists can create a “baby universe,” born in its own Big Bang. Indeed, one prominent theorist she interviews has suggested that our own universe might be a baby universe created by a “physicist hacker,” with the complex pattern of fundamental particle masses intended as some sort of message to us. thereby learning more about the beginnings of the “old” one.

Ms. Merali, who has a Ph.D. in cosmology from Brown University, explains that her interest in this topic is tied up with her religious beliefs: If we ourselves could play God and create a new universe, wouldn’t that creation amount to a theological discovery, showing the likelihood that some higher intelligence was responsible for the Big Bang? She structures her narrative around interviews with prominent theoretical physicists; they mostly discuss science, but religious questions sometimes play a role, with often fascinating results. While some refuse to engage, she gets others to discuss such topics as the relation of the laws of physics to God’s happiness, the possibility of a physical “consciousness field,” and what the quantum mechanics of the Big Bang might indicate about the possibility of life after death and resurrection.

Whether or not you believe in a “physicist hacker,” you have to have some sort of theory that applies to the era before the Big Bang. Around 1980 various “inflationary universe” models were proposed, in which a very short period of exponential growth at the time of the Big Bang provided a possible explanation for some observed large-scale properties of the universe. These models invoked a new, speculative “inflaton” field (and, no, that’s not a typo—it’s analogous with boson, muon, etc.) responsible for the expansion; but the properties of these models had to be carefully chosen to match observations. Ms. Merali does an excellent job of describing the early history of such work, interviewing important figures like the theorists Alan Guth and Andrei Linde, who along with others investigated the issue of whether such models would allow us to make extrapolations about what things were like back before the Big Bang. They also began discussing models of baby-universe creation; by 1992 Mr. Linde had published a paper he first titled “The Hard Art of Universe Creation.”

Mr. Linde is the central figure in this story, and Ms. Merali describes him as “a showman: bombastic, passionate, and fueled by the certain belief that inflation theory, which he helped to invent, is correct.” While Ms. Merali takes all of this seriously, there are very good reasons why most physicists don’t. Readers of “A Big Bang in a Little Room” would be well-advised to enjoy the ride but stay skeptical. Inflationary models can to some degree be confronted with observation and tested (a topic covered in other books but not this one). Attempts to give these models theoretical grounding (such as string theory) also cannot be independently tested: They involve a morass of many different unobservable new entities, inflaton fields among them, with no understanding of the physics of such a system.

Mr. Guth was initially fascinated by the idea of baby universes getting produced and making up a multiverse, though he imagined these other universes would all have the same physics as ours. Ms. Merali relates that he quickly lost interest: Why care much about cosmological models producing not just our universe but other copies we can never observe? Over the past 15 years, however, Mr. Linde’s slightly different argument—for a multiverse of universes, each with different physics, has become very popular. Such a multiverse even provides an explanation for the lack of progress in recent decades toward a better understanding of where fundamental laws of physics come from: The laws we observe are just artifacts of where various inflaton fields happened to randomly end up after our Big Bang; in other universes, the laws are different. Ms. Merali gives a disturbing version of this, contemplating the possibility that “string theory and inflation may be conspiring against us in such a way that we may never find evidence for them, and just have to trust in them as an act of faith.”

Science, however, is fundamentally not about faith but about evidence. One section of “A Big Bang in a Little Room” describes well-advertised hopes from 10 years ago that the new Large Hadron Collider in Geneva might somehow find evidence for extra dimensions, magnetic monopoles or other extremely exotic new physics. Based on this, the jacket copy tells us that “within the next few decades” physicists may be able to use this new physics to create baby universes. This is nonsense, for a list of reasons, beginning with the implausibility of such ideas in the first place and going on to the fact that data from the LHC is now here, and has shown no evidence at all for any of them.

In an era where “post-truth” was the word of the year, scientists and science writers need to make clear that science is not a species of theological or philosophical speculation and not about belief or entertainment value. Legitimate scientific claims are those that can be backed up with evidence, and unfortunately the wonderful and exciting story told well here contains none at all.

—Mr. Woit is the author of “Not Even Wrong: The Failure of String Theory and the Search for Unity in Physical Law.”

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