What did the big bang hypothesis suggests 20 billion years ago?

Answer 1

TWENTY billion years ago? We don't have the beginnings of a clue. We believe that our universe came into being about 14.5 billion years ago, plus or minus a half a billion years to cover the outlier theories. So 20 billion years ago was 5 billion years before this universe exploded in the Big Bang.

Important caveat: we DON'T KNOW if the "Big Bang" happened just the way that some scientists have described it, or if it is somewhat older or a little younger. In fact, we KNOW precious little about things that happened even ONE billion years ago, when this planet was well into middle age. Our theories of the formation of the universe are primarily guesses and conjecture stuck together with a few flimsy facts and a LOT of suggestions. A hundred or a thousand years in the future, scientists will think of us now as the equivalent of the Babylonian and Egyptian astrologers.

So, 20 billion years ago..... Here are a few guesses that don't even qualify as hypotheses.

1. The question is meaningless because time came into being when the universe did, so "20 billion years ago" is like asking a 20 year old person "Where were you 30 years ago?" There was no time, no space, no existence, nothing.

2. There are some intriguing speculations that our universe is one of an infinite number of universes in sequence, like a bead on a string. 5 billion years before the beginning of THIS cycle was the beginning of the heat death of the end of the LAST universe.