Perhaps we shouldn’t be surprised by the multiverse’s ready acceptance. David Berlinski observes, “The idea that everything is really true somewhere has been current in every college classroom for at least fifty years.”
But as orthodoxy? New Scientist told us in 2009:

Until recently, many were reluctant to accept this idea of the “multiverse”, or were even belligerent towards it. However, recent progress in both cosmology and string theory is bringing about a major shift in thinking. Gone is the grudging acceptance or outright loathing of the multiverse. Instead, physicists are starting to look at ways of working with it, and maybe even trying to prove its existence.

Maybe even trying to prove its existence? Yes because, remember, evidence is now superfluous. Methodological naturalism produced the Copernican Principle, which is an axiom. It axiomatically accounts for our universe’s apparent fine tuning by postulating — without the need for evidence — an infinity of flops. And cosmologists’ acceptance makes the multiverse orthodoxy.
Hailed as the “world’s smartest man,” with cameos to his credit on The Simpsons and Star Trek, Stephen Hawking has blessed the multiverse for popular culture. Denouncing philosophy (and religion) as “outdated and irrelevant”, he announced that science dispenses with a designer behind nature because the law of gravity explains how the universe “can and will create itself from nothing.”
Sometimes his pronouncements are less clear, though their outlines are discernible. Ian Sample, science writer for Britain’s Guardian, asked Hawking in 2011, “What is the value in knowing ‘Why are we here?'” Hawking replied:

The universe is governed by science. But science tells us that we can’t solve the equations, directly in the abstract. We need to use the effective theory of Darwinian natural selection of those Societies most likely to survive. We assign them a higher value.

Sample had no idea what Hawking meant. But we can discern this much: Philosophy and religion may not matter, but Darwin does.
How far has the multiverse penetrated our culture? Tegmark observes, “Parallel universes are now all the rage, cropping up in books, movies and even jokes.” Indeed, multiverse models can hardly be invented fast enough, with or without science. Cosmologist Andrei Linde has commented that a scenario that is “very popular among journalists” has remained rather unpopular among scientists. In short, popular science culture needs that scenario.
Multiverse cosmologists look out on a bright future, freed from the demands of evidence. Leonard Susskind writes, “I would bet that at the turn of the 22nd century philosophers and physicists will look nostalgically at the present and recall a golden age in which the narrow provincial 20th century concept of the universe gave way to a bigger better [multiverse] … of mind-boggling proportions.” Physicists Alejandro Jenkins and Gilad Perez say their computer program shows that “universes with different physical laws might still be habitable.” And reviewing theoretical physicist Lawrence Krauss’s Universe From Nothing (2012), science writer Michael Brooks notes that the multiverse puts laws of physics “beyond science — for now, at least.” Before methodological naturalism really sank in, undemonstrable universes, not the laws of physics, were beyond science.
And, as we have by now come to expect, the scheme is undergirded by tinny moralizing. From Max Tegmark: “The price we have to pay is becoming more humble — which will probably do us good — but in return we may find ourselves inhabiting a reality grander than our ancestors dreamed of in their wildest dreams.”
Multiverse cosmologists are now so culturally secure that they no longer need confidence in their own assertions. Andrei Linde confessed, after offering a defense of multiverse thinking, “One can easily dismiss everything that I just said as a wild speculation,” a prospect that does not trouble him much. Leonard Susskind reportedly told Alan Guth, “You know, the most amazing thing is that they pay us for this,” and Nobelist David Gross (the fellow who “hates” the Big Bang) has admitted about string theory, “We don’t know what we are talking about.” But they do know what they are not talking about, and that is enough.
Concluding a defense of the multiverse, Nobelist Steven Weinberg (2011) tells us:

It must be acknowledged that there is a big difference in the degree of confidence we can have in neo-Darwinism and in the multiverse. It is settled, as well as anything in science is ever settled, that the adaptations of living things on Earth have come into being through natural selection acting on random undirected inheritable variations …

Weinberg has faith in Darwin. Not so much in the multiverse:

Martin Rees said that he was sufficiently confident about the multiverse to bet his dog’s life on it, while Andrei Linde said he would bet his own life. As for me, I have just enough confidence about the multiverse to bet the lives of both Andrei Linde and Martin Rees’s dog.

So if there were no multiverse, for Weinberg there would still be Darwin. But now, what of those more confident ones, who know that the multiverse is a Sure Thing?
Image credit: fuchz/Flickr.