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What came first: Inflation or the Big Bang?

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C C Offline
https://www.forbes.com/sites/startswitha...247f3f4153

EXCERPT: . . . Since inflation was first proposed and refined during the early-to-mid 1980s, we've learned a lot about our cosmic origins. In addition to reproducing the hot Big Bang's successes and explaining these otherwise inexplicable initial conditions, it made six novel predictions about properties the Universe should have today, with four observationally verified and two not yet sufficiently tested to know for certain. Among most people who study the early Universe, inflation is accepted as the new consensus theory. We might not know everything there is to know about inflation, but either it — or something so similar to it that we don't have an observation to tell them apart — must have happened.

With all that said, what does that mean for our cosmic origins? From a timeline perspective, what comes first: the Big Bang or inflation? Believe it or not, the above graph [see article] contains all the information you'd need to know for certain. Two of the curves — red and blue — represent a Universe dominated by either matter or radiation. As you can clearly see, if you extrapolate them back arbitrarily to the past, you get an inifinitely small size at a finite time of t=0, which is a singularity.

But if at some early time, the Universe isn't dominated by matter or radiation, but by a form of energy inherent to space itself, you get the yellow curve. Note how this yellow curve [see article], since it's an exponential curve, never reaches zero in size, but only approaches it, even if you go infinitely far back in time. An inflating Universe doesn't begin in a singularity like a matter-dominated or radiation-dominated Universe does. All we can state with certainty is that the state we call the hot Big Bang only came about after the end of inflation. It says nothing about inflation's origins.

In fact, our entire observable Universe contains no signatures at all from almost all of its pre-hot-Big-Bang history; only the final 10^-32 seconds (or so) of inflation even leave observably imprinted signatures on our Universe. We do not know where the inflationary state came from, however. It might arise from a pre-existing state that does have a singularity, it might have existed in its inflationary form forever, or the Universe itself might even be cyclical in nature.

There are a lot of people who mean "the initial singularity" when they say "the Big Bang," and to those people, I say it's long past due for you to get with the times. The hot Big Bang cannot be extrapolated back to a singularity, but only to the end of an inflationary state that preceded it. We cannot state with any confidence, because there are no signatures of it even in principle, what preceded the very end-stages of inflation. Was there a singularity? Maybe, but even if so, it doesn't have anything to do with the Big Bang.

Inflation came first, and its end heralded the arrival of the Big Bang. There are still those who disagree, but they're now nearly a full 40 years of ot date. When they assert that "the Big Bang was the beginning," you'll know why cosmic inflation actually came first. As far as what came before the final fraction-of-a-second of inflation? Your hypothesis is just as good as anyone's. (MORE - details)
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