# Multiple big bangs.

1. Jun 8, 2004

### Reflector

Is it possible that instead of one big bang originating from one singularity there were a number of them in different positions? The reason being the requirement of symmetry. How would the individual big bangs 'know' of each other without c? This question would be answered by quantum 'spookieness' as Einstein described it.... If the big bangs already know of each other without even being connected through c, then you could say that the multiple big bangs occured as one big bang because they knew of each other simultaneously even though they were distances apart.

2. Jun 8, 2004

### Staff: Mentor

Dunno - what was between them?

3. Jun 9, 2004

### Reflector

I imagined them being on different parts of a sphere. Every point on a sphere is a distant r from the centre, so even though the big bangs are on different parts of a sphere, they are all equal distances from the centre. So maybe instead of having a big bang at the centre of a sphere you have many on it's surface area....

4. Jun 9, 2004

### OneEye

Sounds like you're trying to explain the MBR anisotropy structure (which indicates information sharing between opposite "sides" of the universe - implying velocities much greater than c).

A few thoughts: The reason that we have a "Big Bang" explanation for the existence of the universe is that every observed object in the universe is receding from earth. This either means that earth is the center of the universe or that the universe is expanding uniformly in all directions. Astrophysicists opt for the latter explanation (though I vaguely recall that there is some support for the former explanation as well). Projecting this idea backwards in time leads us to the conclusion that the universe was once infinitely small and infinitely dense - the "singularity".

If, as you suggest, there were multiple "seed points" whence the universe expanded outward, then we should see a variety of rates and directions of expansion as we examine all of the stellar objects in the universe. These vectors could quickly be cataloged, and a map of the seed points would today be available.

On the other hand, your explanation is based on the idea that the current expanse of space pre-existed the occurrence of the big bang - that the bang happened outward, into empty space. This is not consistent with the prevailing concept of space. Space - distance - is not a place or a grid, but a relation between moving objects. According to relativity, space is variable depending on one's reference frame. The size of the universe depends on one's velocity - as does the magnitude of the distance between you and any other object.

I am far from happy with this conception of space, but it is necessary in order to support a philosophical point: If space is infinite - or even very large - and the matter of the universe is simply expanding outward into the "empty room" of space, then the part of the universe in which we live is unique compared to the "rest" of the universe, which consists of empty space, yet-to-be-occupied. This presents an unwelcomely anthropocentric view of the universe: That the habitation of man is spreading, in imperial fashion, throughout a domain which was prepared beforehand for exactly that purpose. Such ideas are anathematic to the existential character of modern scientific philosophy.

Hope this helps - or was, at least, entertaining.

5. Jun 9, 2004

### Staff: Mentor

So what is this sphere? What I'm getting at here that it would seem to be included in the definition of "universe."

6. Jun 15, 2004

### Phobos

Staff Emeritus
Sounds like the "horizon problem" which arose from an older version of the Big Bang theory which had trouble explaining the homogeneity of the universe (in that information could not be communicated fast enough across distant parts of the universe to keep everything homogeneous). As I understand it, inflation theory (modification to Big Bang theory) helped explain this in that the points of the universe were closer together in the first few instants than as modeled by the older Big Bang theory. Alan Guth's "Inflationary Universe" has a good discussion of this.