Big Bang

[wesgerrard]

What was there before the big bang?

[Clanad]

No one knows... in fact no one knows what existed before 10-43 seconds after the event... Planck Time...
tP = (G / c5)1/2≈ 5.391 � 10-44 seconds...

[boobesque]

some say nothing. but try to imagine nothing. really. no space, no vaccum, nothing. surely we can never know as we cannot really percieve what we cannot experience.

[curlyfilm]

was there a big bang that created the universe?
if you travel across space, you are travelling through nothing but there must be something there as how could you travel through nothing
i always prefer the constant state universe that say say the unverse has always been here and always be here,
because how could the universe just appear out of nowhere, also what at the end of the universe? i think it just goes on and on
surely someone more intelligent, can enlighten us,

[Clanad]

Problem is curlyfilm current investigation firmly supports a beginning, hence an eventual total dispersion with no steady state... Additionally, there's not nothing in space. It's surprisingly well populated by this and that...

[scotstone]

There is no before. Time started at the big bang.

[alvin100]

god i hate this question as it just makes your head hurt to think about it, Our human concept of time just doesnt work when you try to imagine the beginning of the universe, there must have been something there before, and what was there before that?
ARRHHHHHHHHHHHHHHHHH My head

[mibn2cweus]

Time is relative. Without a star with a spinning planet revolving around it, what would define the meaning of a day or a year? Without a photon or a universe for it to traverse, what would the velocity of light or the distance of one light-year mean? Neither of these or anything else of which we possess any knowledge or any means to understand existed until the "Big Bang" was already in progress. The sum of the accumulation of our present knowledge provides us with no evidence to reasonably speculate about what took place (if anything) before that time. The "Big Bang" is an insurmountable brick wall to all mathematical models that describe the physical processes of our universe. We�re trapped!

Don't feel too bad about this as I feel fortunate when I can remember much about what happened the day before yesterday.

[poeima]

The big bang is not provable or testable�which remain completely theoretical and the models they support are based on unprovable starting assumptions.

[doglady]

Don't think about it, you'll hurt yourself!

I don't think people's brains are designed for thinking about this. It's like thinking about what is outside the universe. If it's expanding, what is it expanding into.

Ugggghhhhhh. I'm going for a lie down now.

[Clanad]

poeima is correct, but only to a point... that point being the aforementioned Planck Time... Current measurements of many different types have clearly shown the universe to have had a starting point (in time, not location), that it continues to expand at a great rate of speed and that the speed of expansion increases exponentially the farther in time back one is able test... This has been the biggest thing in the astronomy field since... well, sliced bread... and the implications still reverberate (pun only slightly intended) throughout the scientific community...

[jake-the-peg]

I'm not sure that poema's point is really valid at all.

I might argue that I have a sealed box at home and because nobody looked in it today a hamster suddenly came into existance in there and then vanished!

Nobody saw it so noboy canprove that it didn't.

As Clanad Alludes there are infact 2 very strong pieces of evidence supporting the big bang. Firstly the Universe is expanding and if you run that back you get an initial start. Secondly we see the background radiation. This was predicted before it was found then a couple of scientists found it by accurate - the same in every part of the sky and pretty much exactly what was predicted.

Now if you don't believe in the big bang you've got a lot of explaining to do to explain those 2 phenomina away!

But Clanad answer also demonstrates the problems in talking about there in english - how can you have a starting point in time or location when neither time or physical dimension have any meaning?

Even if it were possible to comprehend some of these concepts, we certainly don't have the tools in the English language to express them.

[curlyfilm]

but there must be no end to the universe, and call me stupid all you like but the universe did not suddenly appear, its just simply been here all along,


sorry i can't think about it too much, it hurts me head, ouch

[THECORBYLOON]

The Universe is expanding but what's it expanding into?

[jake-the-peg]

Curlyfilm - I may have a nasty shock for you :c) - time doesn't work like that - you may think time just goes on and on the way we all experience it in our every day lives.

But when you start looking at extreme situations like very high speeds or gravity time starts 'misbehaving' and all the things you thought you knew about time starts to fall apart in your hands

Much the same with space you just can't assume that everyday notions of space and time mean much in these extreme cases.

The so called field equations of General Relativity describe how space is bent by mass and there are different solutions to them. They don't necessarily have good analogies to the world we think we know.

Basically this is afield that you simply cannot apply "common sense " to you have to use Maths - It's not too unreasonable really there's not much common about the birth of the universe

[dawkins]

actually I think the answer is a gravitational singularity. Clanad is , of course, correct to point out that the big bang model excludes quantum effects but the nuts and bolts of the theory are that the universe was squashed into a singularity infinitely small and dense with infinitely curved spacetime.

Then the big bang happened and since then everything has been expanding away from that singularity either forever or eventually to be attracted back into a singularity in what is known as the big crunch.

D

[curlyfilm]

this may happen in our part of the universe, but how can this happen to something that is never ending

[dawkins]

Is that to me Curlyfilm?

The Universe is not never ending. If it was never ending it would not have a starting point before the big bang and it would not be able to expand. See this link for an estimate of the size of the universe:

http://www.space.com/scienceastronomy/mystery_ monday_040524.html

D

[Clanad]

I'd guess I have to point out, dawkins what appears for you, to be atypical incongruencies On the one hand you infer, that since the Universe had a provable beginning that it will have a big crunch. No studies I've seen infer that at all. Current guestimates are that the universe will continue to expand and in fact expand at even a faster rate than it is now. Then you propose to curlyfilm that since the universe had a beginning it is not never ending and wouldn't be able to expand, because, circularily, it had a beginning. Although the current measurement of the size of the universe (width wise) is 156 billions of light years it's also known that this is a temporary measurement since the thing being measured is still expanding exponentially with no indication of ever slowing. In fact a sub-link in your posted link discusses that very aspect. The last paragraph in the sub-link is instructive..." The acceleration is likely to continue, most of them believe, until galaxies recede from one another at the speed of light and can no longer be seen. One new theory goes further, suggesting that every speck of matter in the cosmos will ultimately be torn apart in a universe-ending Big Rip."
Usually, you are quite succinct, but this latest of yours doesn't make a lot of sense, at least as stated... no? (To much coffee, maybe?) As a quick addendum, most astrophysicists, at least in my limited perusals, don't agree that the "... universe was squashed into a singularity..." most agree that it came into being ex nihilo... and then attempt to explain the consequences so implied...

[druiaghtagh]

My brain hurts