Over the last decade physics has struggled to explain the very fine-tuned nature of our universe. I am a fan of Dr. Woit and his website [http://www.math.columbia.edu/~woit/wordpress/], “Not Even Wrong.” One of the proposed explanation for it is the multiverse theory. Voit and many other physicists emphasize that the multiverse theory is unprovable with our current with our current state of technology. Following is from Woit’s website for Dec. 6, 2017 about a talk by 2018 Breakthrough Prize symposium winner David Spergel:
“Well, alright, I’m going to say something that I probably shouldn’t say in Palo Alto. I don’t think the multiverse is a testable and interesting scientific hypothesis. I think it doesn’t explain anything.
“The way the multiverse tends to be used is together with the anthropic principle. The idea is that the universe is the way it is because that’s the way we get to live in it. I find the multiverse solutions to these problems, it’s a lot like if you ask me “why am I wearing a black shirt today”. My answer would be: “you wouldn’t have asked the question if I wasn’t wearing a black shirt”. That’s not a satisfactory answer.
“The way we have advanced in science is by fallibility. By developing hypotheses, testing them (that’s why we do experiments) and ruling things out.
“Ideas that are not testable, it’s interesting metaphysics, perhaps interesting for philosophers. What has driven four hundred years of scientific progress is the fact that ideas can be wrong. And, the multiverse, I think is kind of the last refuge of cowards… That’s why it’s great to have tenure.”