big bang theory

[caxton]

If the universe started according to the generally accepted "big bang" theory, then should not the centre of the universe be an empty space if all the matter has accelerated away from the original event. This however does not seem to be the case

[Teddio]

There is no centre to the Universe. Every point in our Universe could claim to be the centre. It is not correct to think of the Big Bang as an explosion hurling material outwards into the vacuum of space. The Big Bang created time and space and matter. You can't stand outside the Universe and see the matter expanding towards you. The analogy of an aerial exploding firework is a very poor one.

[claymore]

dark matter is expanding the universe in all directions; therefore how can we say precisely where the Big Bang took place

[meredith101]

It happened is Chelmsford. That's why when you drive into Chelmsford all the signs say 'Welcome to Chelmsford, centre of the Universe'.
Check it out.

[jake-the-peg]

Careful claymore I think you're mixing up dark matter and dark energy.

Dark matter is whatever is responsible for the extra gravitation that we see happening but can't account for with the matter we know is there.

Dark Energy is what is driving the acceleration in the universe's expansion.

This is a common misunderstanding Caxton - the big bang was not a giant expansion into existing space.

Space it'self the three physical dimensions and even time were created in that event.

Think of it as a bubble in water that appears and expands, the bubble gets bigger and bigger and points on the surface accelerate away from each other.

No point on the surface of the bubble is in the centre.

You need an additional dimension for that. Similarly if there is a centre it would be in a fourth physical dimension.

[Clanad]

Perhaps a depiction of the most prevalent theory will help understand the architecture of the event:

http://aether.lbl.gov/Images/resizenowmap.jpg

Additionally, the actual shape of the existing universe is thought to be one of these:

http://map.gsfc.nasa.gov/ContentMedia/990006b. jpg

[jake-the-peg]

Er kind of those diagrams are a little misleading as they a) are 2d (obviously) but b) represent open, flat and closed universes.

For example - remember the game asteroids? your space ship goes off to the right and comes back on the left etc. off the bottom, comes in the top

If you think about it you'll realise that that is like a torus, or a bagel shape.

The universe could be like that in which case it'd be like a 4 dimentional torus - that'd be represented by your sphere as it has positive curvature but would look more like this
http://www.sensable.com/documents/Galleries/Vi deos/4DTorus.wmv

[Clanad]

Nice graphic, jake!

[kwicky]

I suppose if the universe is shaped like a torus an analogy could be made with a smoke ring exhaled by a smoker. The difference in scale is massive but the principle still holds. Can it be disproved?

[jake-the-peg]

Well it would have to be a 4 dimensional smoker and a 4 dimensional smoke ring :c)

[kwicky]

I always understood the 4th dimension to be 'time'?