# How can the big bang allow infinate universes

1. Apr 18, 2013

### 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 dont understand how a big bang can allow an infinate universe. If there was a starting point at the unverse exapnd at a non-infinate speed then how can it be infinate 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.

2. Apr 18, 2013

### Staff: Mentor

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.
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.

3. Apr 18, 2013

### 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
I hope this helps,
Garth