big bang theroy

[shoddy]

is it true that before the big bang we all existed before until the big squeezze my mate reckons we are all gonna live forever banging and squeezing for eternity

[bernardo]

That is a theory, so yes it may be true or no it might not be true. One theory is that the universe is constantly fluctuating up and down in a never-ending sequence of big bang - expansion - contraction - big crunch. (Physicists call it a "big crunch", not a big squeeze). Another theory is that the universe is only one among many, a bit like a single bubble in a pan-dimensional turbulent frothing "multiverse" where individual universes are constantly forming, splitting, merging together, expanding, squashing etc. like in a big frothy soapy thing.

[thekraut]

what kind of theory is that about banging for all eternity?

[bernardo]

It's the theory about an endless repetition of banging and crunching - with occasional brief spontaneous outbreaks of culture and intelligence in between, but with mostly a swirling cauldron of fog and clouds and dust and stars and volcanoes and swamps and thingies.

[Bob A Job]

This theory has since been disproved using data from the hubble space telescope. The difference between the 'Red shift' of nearer stars than further stars gives us a rate of acceleration of expansion of the universe. and this acceleration is to higher a rate for the total mass of the universe to ever 'crunch' back in again. So the universe will expand for ever until the stars burn out and all thats left is dust and rocks in utter darkness. not a very glamorous ending huh.

[shoddy]

thanks bob a job for that answer but what about dark matter was it decided that the mass was only about 10 of what was needed to stop the expansion\big squeeze then came along dark matter to make up the other 90% so the brakes will go on and it will start al over again

[Bob A Job]

The 'dark matter' you speak of was already factured into the equation. Even though dark matter is supposed to be a large quantity of the universal make up, it is still insignificant compared to the rate of expansion. Gravity's effect would have to be approximatley 1.7 times stronger than it actually is to allow a crunch to happen.

[ludwig]

If the universe is all there is, how can it be expanding. Surely it must have always been the same size - ie 'universe size'.

[Bob A Job]

Whats outside the universe..? Impossible to answer, as we can only concieve the universe in 4 dimensions. can a sheet of paper imagine a sphere? Maybe there is space but no time, so nothing happens. Maybe there is time but no space so nothing CAN happen. Maybe there is matter but no light, so we cant see it. Maybe there is light but no matter, so we still cant see it The way i see it there is SPACE, TIME, MATTER, ENERGY, all seperated and where they meet becomes the known universe. like strands of string twisting together to make a rope. Five dimensionally speaking of course.

[Bob A Job]

sorry, didnt answer the question the universe is still the same size its always been, kind of. In the same way that a ballon is the same size whether it is blown up or not, its just stretched. but at the same time its also expanding, as a result of the 'Big Bang' into what it is expanding i tried to answer above.

[bernardo]

Q. from ludwig If the universe is all there is, how can it be expanding. Surely it must have always been the same size - ie 'universe size'.

A. The universe (as we perceive it) is the three-dimensional surface of a 4-(or more)-dimensional hypersphere. The hypershere is expanding into another dimension, so the universe stretches with it.

[shoddy]

bob a job if we are moving on to strings should we not consider 11 dimentions as this mathmatically is the only solution and how can there be matter and energy are theses not the same thing

[Bob A Job]

well, if you want to get that finiky, Energy is mass and vice versa E = MC squared remember!

[shoddy]

sorry bob a job dont want to be finiky but we are geting in to deep one more question will the universe slow down and stop expanding at some point in the future

[ludwig]

I've seen the balloon analogy before. Blow it up and everything on the surface moves apart. So, (and this is relevant to shoddy's question), at what point does the balloon start to deflate? what triggers the start of the crunch?

[ludwig]

..I once saw a bloke on the telly trying to explain this stuff, and he said something like 'one trillionth of a second after the big bang the universe was about the size of a pea'. Which made me roar with laughter. I thought 'no it wasn't - it was the size of a universe you muppet'. I guess I'll never understand it really.

[Bob A Job]

in a difinative answer, 'So the universe will expand for ever until the stars burn out and all thats left is dust and rocks in utter darkness.' Quoted from above. this is agreed by nearly all scientists in this field of research.

[Waltonator]

We certainly wont live forever - at the next big crunch (if it happens) we will be squeezed into an infinitely small space.