Something's been puzzling me, why is it considered that at the time of the big bang, the universe started by expanding "normally" then, underwent a period of accelerated expansion, then went back to "normal"?

 

Could it not have started out at the increased expansion rate (inflation from the very start of the universe at the big bang), before settling into the rate we see now?

I was thinking about an idea that ther may be more than one dimension of time, which (like the fundemental forces) overlapped when the early Universe was so hot and dense, and after the Universe had expanded and cooled past a critical point, the two dimensions of time seperated, and so we notice the effect of only one temporal dimension.

 

Although saying that, it could also be that the spacial dimensions could have been combined at the start of the Universe, to explain why expansion *seemed* to have gone faster than that which would be allowed by today's laws of nature.

I read in a book titled "Blackholes, Wormholes and Time Machines" that the rate of expansion is due to a critical amount called omega.

 

I guess flutuations in this value caused the rate of expansion to fluctuate after the big bang.

 

This number is related to the relative density of the universe and also dictates whether it is negatively curved and open or positively curved and closed.

Who's that book by? It sounds intersting.

Jim Al-Khalili