/sci/ - Science & Math

>>11650946

So what sort of mad physics could do something like that? Actually, Einstein came up with the exact mathematical description that we need-- an antigravity term called the cosmological constant. In the field equations of his general theory of relativity, he added this as a way to allow his theory to describe a static space time, a universe that's neither expanding nor contracting. When it was later discovered that the universe is indeed expanding, Einstein retracted his constant. But this bit of math gives us exactly the type of expansion that we need for inflation. Incidentally, it also describes the effect of dark energy, and that may not be a coincidence. The cosmological constant represents something that can happen to our spacetime. Einstein is right, even when he's wrong. The cosmological constant adds some energetic stuff to empty space. It doesn't tell us what this stuff is, just that it's a property of space itself and that it acts to drive expansion. The more space, the more of this stuff. And so the more space, the more expansion.

What could cause such a weird sort of energetic vacuum? Inflatons, scalar fields, forced vacuums, all of that. For now, let's just go with the fact that empty space can propel its own expansion and will do so if the vacuum contains a ubiquitous constant energy density. Another really important thing about the driving mechanism if inflation is that it stopped. The universe slowed down from exponential to the regular old expansion that we see today, what we call Hubble expansion. And while we know the minimum amount of inflation needed before that stopping point, we don't really know when it began or even if it had a beginning. It may have, and there are some ideas about what got it started. But it's also possible that inflationary expansion is the default state of the greater universe-- I should say multiverse at this point. This is the idea of eternal inflation.

1/(cT)^2 = 0.7*10^-56 1/cm^2

T: age of the universe (sec)
c: speed of light

Checkmate atheists.

Alright guys, the Cosmological Constant. It's spooky. How can it be such an extraordinarily precise value and how can it be that value and only that value would give rise to the universe we live in.