Why I do not believe in the multiverse
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The multiverse, the idea that the universe is constantly splitting into parallel copies of itself, appeals to atheists and determinists alike. It offers a philosophical way out of the anthropic question: why does the universe seem uniquely suitable to our existence? It lets us know that the universe is not random but that nothing is pre-destined to happen, even our existence.
The problem with it is that it fails Ockham’s razor and rests on the most tenuous physical arguments. It tells us that not only are there an infinite number of alternate realities out there but that this must be so because it is the only way to explain quantum theory coherently. The latter statement is hardly true, and the strawman argument that its only rival is something called “wavefunction collapse” is also false.
The anthropic principle meanwhile that the early universe actually produced an infinite variety of universes, mostly empty, and ours just happened to be the one suited to our existence is a Bayesian argument. Bayesian arguments are expressions of what we don’t know, not scientific theories. They are hypotheses based on how we think the universe ought to work. We don’t know why the universe has the properties it does suitable to the formation of galaxies, stars, and planets. To say we evolved on planet Earth and not a lifeless moon because of the anthropic principle makes sense, but only because we know that such moons exist.
To say that the universe is one of many parallel ones is just one of many possible explanations. Being confined to this point in time and space in a potentially infinite universe where we have only been observing its expansion for the last 100 years, we can hardly make such bold claims. The answer is neither “we are special” nor “many universes”, it is “we don’t know”.
I’m not going to beat around the bush here: I don’t believe in the multiverse. Not only is it scientifically premature, I think it is logically weak too, on par with the simulation hypothesis in terms of philosophical merit.
The multiverse or Many Worlds Interpretation (MWI) of quantum theory is a specific version of the age-old philosophical idea of multiple realities. Introduced in 1957 by Hugh Everett III, a student of two titans of American quantum physics, Wigner and Wheeler, the…
