A team of scientists has proposed a groundbreaking new theory on the Universe's origins, offering a fresh, radical take on the Big Bang's early moments. Unlike the widely accepted inflationary model, which involves speculative assumptions, the new model starts with the established concept of De Sitter space, aligning with dark energy observations. The scientists believe gravitational waves—ripples in space-time—were the key to seeding the formation of galaxies and cosmic structure, eliminating the need for unknown elements.
Ooh, I like this idea! I’ve always found physics (especially cosmology) to have a few too many handwaves around some pretty odd ideas. Renormalization for one. The rapid inflationary model for another. It’s just a silly suggestion. “The big bang happened, but then the universe expanded super fast for no reason before it slowed way down also for no reason. Inflatons maybe?”
An emergent model based in interactions of known forces would seen much more sensible to me.
There’s nothing handwavy about renormalization, it’s just a way of describing the mathematics which is easier for a human brain to deal with, so we’ve standardised on it.
An unnormalised wave function can show you the relative probability of any given thing, but it makes like easier if you set the scale so that you can read an actual probably straight off it, rather than having to ask “relative to what?”
A couple notes:
First, renormalizarion was hand-wavy when it was first introduced, but it has since been made mathematically rigorous. Additionally, renormalization is a mathematical process to make a theory self-consistent. If you consider it an odd idea because it is physically nonsense, I would caution against forming a physical intuition from any given accurate mathematical model. Especially with fundamental quantum mechanics—there’s a reason why there are several interpretations of QM and have been for a century.
Second, and arguably more importantly: this ScienceDaily article is extremely misleading. The original paper (linked by OP in another comment) says
So the paper does rid itself of the inflaton field, which is, as you said, a bit of a hand-wave. Crucially, however, it does not abandon inflation—in fact, it explains those “for no reason”s that you mentioned.
i don’t understand how super fast expansion following the big bang can be described as “for no reason”
(I’m not a physicist) I think the rapid inflation proposed didn’t begin at the instant of the big bang but a little later