How can the big bang allow infinate universes

[yup790]

For my physics teacher I had to reaserch and wriet about parrallel universes. I understand the many big bng theory and the many worlds interpretation for universes.

However, i don't understand how a big bang can allow an infinite universe. If there was a starting point at the universe exapnd at a non-infinite speed then how can it be infinite in size. I understand that from each point there is a different observable universe as, as I believe, the universe loops around itself like the surface of Earth does - ish.

Please help

 

[mfb]

There was no starting point in space, just a starting point in time. If the universe is infinite in size, it has been infinite all the time.

the universe loops around itself like the surface of Earth does - ish.

That could be true - we don't know. In that case, the universe would be finite but without boundary, just like the surface of earth.

 

[Garth]

There might not only be an infinite universe, but an infinite number of them!

Basically the trick was to think of an idea to explain how the universe/BB could pop out of nothing.

Once you have convinced yourself of a way that could happen then the problem would be getting the process to stop! Universes would pop up out of nothing 'all over the place'!

Hence an infinite number.

You might like to look at Eternal Inflation.
Or Linde's paper Eternal Chaotic Inflation

It is shown that the evolution of the universe in the chaotic inflation scenario has no end and may have no beginning. According to this scenario, the universe consists of an exponentially large number of different mini-universes inside which all possible metastable vacuum states and all possible types of compactifications are realized.

I hope this helps,
Garth