Looking through the astronomy materials at a branch of the local library, three new books from the last three years stood out:
- Brian Greene, Until the End of Time: Mind, Matter, and Our Search for Meaning in an Evolving Universe (New York: A. A. Knopf, 2020)
- Jorge Cham and Daniel Whiteson, Frequently Asked Questions about the Universe (New York: Riverhead Books, 2021)
- Tony Rothman, A Little Book about the Big Bang (Cambridge, Massachusetts: Harvard University Press, 2022).
All three of these books feature “The Multiverse”. Our universe happens to have certain choice characteristics that allow us human beings to be here. It is easy to imagine all sorts of universes which would be inhospitable to humanity. So, we seem to have gotten very, very lucky with our universe. The Multiverse supposedly explains how we got so lucky, by postulating the existence of an infinitude of universes.
With a multiverse, our lucky universe must exist of necessity—because in an infinitude of universes, every possible universe, no matter how improbable, must exist, and must exist an infinitude of times! If you buy an infinitude of lottery tickets, you necessarily will have every possible winner, infinitely many times. No luck involved.
This is the modern, secular version of what was once called The God of the Gaps. With the classic God of the Gaps, when science can not explain how things are, God is invoked: “God did it”. Now the answer is, “The Multiverse did it”. Like God, The Multiverse is infinite, eternal, exists of its own nature, is the cause of all that exists, etc. Unlike God, The Multiverse does not care if you steal your neighbor’s beagle.
Rothman has a very skeptical attitude toward The Multiverse. He relates how in 2020 someone asked the eminent cosmologist James Peebles if he believed in The Multiverse. The answer: No. Period. Neither does Rothman (page 195). It is “the epitome of ‘post-empirical’ science [pg. 197]” in that there is “no way to test the multiverse concept” scientifically.
Yet “the press and the public are fascinated” by The Multiverse, and the idea “has been in the spotlight for well over a decade [195-196]”. And, Rothman notes, ideas like The Multiverse do excite people and prompt them to study cosmology. But he concludes his book by arguing (204-206) that some things are just beyond the reach of science. He gives love as an example.
Cham and Whiteson, by contrast, run with the idea of a multiverse. They especially run with the idea of “another you [33-49]”. If there is an infinitude of universes out there, they write, then “there is an infinite number of you [48]”.
Green runs with it, too. He imagines universes “where alternate realities play out”—all possible realities, in fact, playing out infinitely many times each. Therefore, somewhere, the assassins who targeted Kennedy and King failed, and the one who targeted Hitler did not (307). Of course the press and the public are fascinated by this.
People I know are fascinated by the idea of a multiverse. I friend of mine, “Fred”, recently commented to me that he finds the idea of alternate realities with other versions of him very appealing. I do not think that he, or most of the rest of the public, and the press, has really thought this through.
If there exists an infinite number of Freds, then yes, all possible Freds, in all possible realities, must exist. That includes those realities in which Fred achieves greatness. But… it also includes those realities in which he most certainly does not.
What realities could there be that might really appeal to Fred? Perhaps ones in which he is fabulously rich, and a great philanthropist; or in which he discovers a cure for a dread disease; or becomes widely acknowledged as a saint. But what about the other direction?—the one where Fred is the assassin, or the Hitler—or the serial abuser, or the workplace mass shooter, or the grocery store mass shooter, or the kindergarten mass shooter, or any of the other dark figures that cast such lengthy shadows across the news today?
So why then is there this fascination with the idea of a multiverse? Cham and Whiteson are of the opinion that “a lot of physicists [40]” are attracted to the idea (not just the public and the press), and think that other “yous” are “more likely than not [34]”. If we are going to invoke post-empirical science to explain, as Cham and Whiteson put it, “why the universe seems to be so choosy [44]”, is not saying “God did it” a more rational option to explain that choosiness than an infinitude of mass-shooter versions of you?
Note—I am not saying that a God of the Gaps is a good idea. Nor am I saying that science proves the existence of God, or that God must be invoked to explain the habitability of the universe. What I am saying is that God seems to me to be a far more rational and appealing post-empirical explanation for our lucky universe than The Multiverse and the infinitude of mass murdering, serial-abusing versions of each of us that necessarily go with it. I don’t think this is too hard to see. I am perplexed by the wide-eyed, uncritical discussions of The Multiverse that appear in, for example, certain books.
So God bless you and send you a Happy 2023! May we hear less this year about multiverses, alternate realities, other versions of ourselves, and the rest of that post-empirical non-science. May the 2023 additions to the astronomy shelf of my library be free of this stuff as well.