Slashdot Mirror
Why We Think There's a Multiverse, Not Just Our Universe
An anonymous reader writes "It's generally accepted that the Universe's history is best described by the Big Bang model, with General Relativity and Quantum Field Theory as the physical laws governing the underlying framework. It's also accepted that the Universe probably started off with an early period of cosmic inflation prior to that. Well, if you accept those things — as in, the standard picture of the Universe — then a multiverse is an inevitable consequence of the physics of the early Universe, and this article explains why that's the case."
But the turtles appear out of nowhere and are very far apart.
Why do cosmological theories of any merit always sound like they were written by Douglas Adams?
Please do not read this sig. Thank you.
or something less stupid, instead?
It doesn't make any sense to say that it's one big thing, but not one big thing at the same time.
Kind of like saying it's not one big cake sliced into wedges, it's lots of little cakes that have nothing to do with each other.
AND YET THEY OCCUPY THE SAME PLATTER.
I know it's karma suicide to post on something like this saying "I don't get it", but, well, I don't get it.
I've been reading about inflation, multiverses, and whatnot for a very long time at this point, and I like to think that I can give a reasonable explanation comprehensible to nontechnical people. I've come across some articles that were a lot of work to get through, and I've given up on some because I don't have the necessary math.
But this article was terrible. Its grammar is good and not overly complex; it doesn't use a lot of obscure words. It's written like a nice popularization piece, with important parts called out in bold and lots of illustrations. But the illustrations are baffling -- what's that "getting closer to a sphere" four-panel diagram credited to Ned Wright, and where does the text refer to it? What the heck is going on with those diagrams from Narlikar and Padmanabhan? What's with the black space-balls rolling around on the mini-golf course at the end?
I'd wonder if this is a Sokol-type troll, but I don't see anything obviously wrong in it -- there's just a bunch of stuff there that looks like explanations, but apparently isn't. Or maybe I'm just having a bad night.
I disagree that he's only defined causally disconnected regions; this story actually has a definition of multiverse beyond regions outside of our lightcone. Note one of his later images: a single level 1 universe contained multiple regions which are not causally connected yet are part of the same clump that moved from the false vacuum to dumping energy into matter and radiation.
Any grouping like that is fundamentally isolated because the boundary region that remains in the false vacuum continues to exponentially expand, quickly isolating the clump. Even if the clump itself triggers a conversion of the false vacuum around it, it sounds like the isolation proceeds so much faster that it will be forever isolated by expanding false vacuum regions. With time, we could reach places that are not currently causally connected. It doesn't sound like we could overcome this expansion so easily.