BBC Focus Magazine

[scott fairbrass]

if the universe was created from one point in the universe, at the point in space where the big bang started there should be nothing but space and this space should be getting bigger and bigger as we expand away from its origin, so the universe is a sphere with a 'empty' sphere with in it? would i be correct in thinking that?
And if thats the case useing a A4 piece of paper were as a map of the entire universe where abouts on the paper would we be?

[...]

the uni wasnt created/manifested (take your pick ) at a point in itself, the theory says there was absolute nothing, now this isnt the normal everyday nothing, like having nothing in your pocketses or a glass with nothing in it, no no no this nothing has no space no time no vacuum, its not "empty" cos theres nothing to be empty, it is boundless with no other dimensions going on anywhere, as another dimension would form a boundary, truly an infinity and this is were big bang theory really fails for me, and why the theory starts a little bit after the event.
nothing could not have existed in the past because we are here, and this implies that something happened to nothing, the only thing that can happen to nothing is nothing.
i know we hear of the random fluctuation of energy popping up and going out in the vacuum of space and this is sometimes nodded towards but this is happening in something, the vacuum,
whats the uni expanding into, nothing, so there is nothing to measure this expansion against who says its expanding, a few red and blue lights.........

[Shadowwolf]

As you might have gathered it's complicated and certainly the verse cannot have been created from a point within itself, such is impossible. With the Big Bang event - which is not an explosion in the conventional sense - what we call the verse, everything from space to time itself was created, the event did not happen in space or the verse, it created space, it created the verse. As Mr ... indicates, the theory has nothing to say about what came before or what and where the event happened; the theory deals with the event and what happened after, nothing more and thus you should not expect it to supply answers outside of its remit.

Because it created the verse there is no point of origin, nor is it like an explosion with everything radiating out from a central blast point into whatever medium the explosion occurred within. Thus the expansion of space is not a shockwave spreading out from a point of origin but space itself expanding / stretching and taking what is in space with it. Imagine a balloon with pennies stuck to it, as you inflate the balloon the pennies stay exactly where they were stuck on but will rapidly depart from each other; in a very basic sense, this is what is happening in the verse.

The shaped of th verse is a matter of debate, I think spherical is one but there are others like flat and hyperbolic, Wiki has a decent intro.

Hope that helps and needless to say, you should pay no heed to certain imaginary fancies by people who confuse imagination with reality.

[...]

@@ if you dont mind shadders

[Shadowwolf]

So noted

[scott fairbrass]

thanks for that, just when i thought i was kind of understanding the basics, someone says something that just confuses me all over again! i pictured the big bang like a ballon expanding. i thought the colour of light we view from outer space proved that we were expanding because the wavelengths were been stretched?

[Nails]

Funny, I've just linked to this in another post!

Lawrence Krauss did a talk a few years ago about the universe coming into being - from nothing.

http://www.youtube.com/watch?v=7ImvlS8PLIo

[darthsmaull]

Hi - the balloon expanding analogy is one I use with some of the groups of kids I teach, but it does have several shortcomings:

What's expanding is the surface or skin of the balloon - essentially 2D - so if you stick on pennies (or my preference is to draw blobs) it is the distance on the skin of the balloon between the pennies that increases.

You could (slightly more) usefully think of something like an uncooked fruit loaf being cooked in an oven and expanding in three dimensions but you've still got the inherent flaw that the loaf (or whatever) is expanding into pre-existing space, which, by definition, isn't the case with the universe...

The balloon idea is a nice demonstration through because it is visual, and, once you've blown up the balloon, you can then let it deflate to illustrate how scientists made the leap from observing that the universe is expanding to coming up with the Big Bang theory.

[M Paul Lloyd]

Hello and welcome darthsmaull, yes the balloon analogy works well but I'm left wondering how does that fit with big bang theory for a Universe that is said to be essentially flat?

[Shadowwolf]

Well I think that's what Mr Darthsmaull was getting at Mr M, it's an analogy that is an adequate but limited way to demonstrate the expansion of space. However, it should not be taken as a complete model of the BBT no more than the theory's name should be taken as indicating a literal explosion.

The balloon shows how otherwise relatively stationary pennies move away from each other as the fabric they are on stretches, how the further pennies are from each other the greater the apparent rate of separation is. This demonstrates where the apparent faster than light speed of far off galaxies originates, that it is an illusion caused by distance and the expansion of space and not a galaxy physically breaking the light barrier. The balloon analogy is not meant to imply that the universe is either roughly spherical or that it expands into something and so has no bearing on anything outside of demonstrating how expansion works.

[M Paul Lloyd]

I'm with you Mr.S but does our bit of the universe appear flat due to it being part of an infinitely large 'balloon like' curvature that just appears flat or is it actually 'flat'?

As I understand it, if the expansion of the universe is accelerating then this suggests that the universe is geometrically 'flat'.

I'm just wondering if that is just an illusion or backed by observable evidence?

[...]

ive heard this "flat universe" thing before but cannot grt my head around it.
one thing we know for sure is that the verse has a least 3 dimensions, up, down, left, right, back and forth. anything that is flat has only 2D so the verse cannot be flat.......or am i missing something?

[darthsmaull]

ive heard this "flat universe" thing before but cannot grt my head around it.
one thing we know for sure is that the verse has a least 3 dimensions, up, down, left, right, back and forth. anything that is flat has only 2D so the verse cannot be flat.......or am i missing something?

I'm by no means certain I have got my head fully around this either, but from what I do understand it doesn't mean that the universe is two dimensional. What I think it is getting at is whether or not space is curved - with "flat" meaning that it NOT curved.

[M Paul Lloyd]

Yes it is rather confusing isn't it?
Basically it is either curved like a bowl or curved like a ball, or its flat, but not, as mentioned, two dimensional.
Needs looking into I think.

[scott fairbrass]

apart from the big bang theory then is there any other theories out (apart from the bible of course)? And are they any closer to determining the existance of the univers!

[Shadowwolf]

There are other theories but none are as well supported by evidence as the BBT, hence why it is the dominant explanation for the evolution of the universe. You can check out three of the best alternates here, but remember that whilst they are alternates they do not come close to the explanatory power that the BBT does, any alternate must go beyond the BBT to amend our current approach. If an alternate were closer, as in better, then it would be the accepted model and not the BBT.

Btw the Biblical account is no more a scientific theory or credible alternative than me claiming that the verse was the result of great cosmic dragons battling each other. It's an assertion without evidence and not in accordance with what we have discovered bar the most superficial coincidence of language; basically it's not a theory.

[Thinker]

oooh! The Cosmic Dragon Theory! I like that. Maybe the dragons started with a jolly old game of chess, but after a bout of 20,000 stalemates they realised that it was going to come to a fight to the death. The Grey Dragon of Oregano struck The Mighty White Lizard square on the tail and released an infinite amount of matter into the land otherwise know as the Universe.

[The Beige Avenger]

There are also other "bibles" that offer other ideas... for instance Hinduism states that the universe expands and contracts cyclically.

I quite like this idea.

[M Paul Lloyd]

Yes a cyclic universe used to hold some sway in the scientific community back in the day.... but sadly not just now.

Anyway, fact is the original idea for what subsequently became known as the 'big bang' was actually formulated by a catholic priest by the name of Monsignor Georges Lemaître, who based his calculations on the Hubble expanding universe observations and postulating that everything must have originated in one small part of space, and although his concept fell rather short of the actual and really quite complicated theory required to support such a notion but one can only wonder at his motives given the literal translation of the biblical genesis...ראשׁית rḕshı̂̂yt 'In the beginning'

[Shadowwolf]

That's my point on language, a bare and not too accurate similarity, a most tenuous of links as the story from after the point of, "in the beginning," bears no relation whatsoever to the BBT or Lemaitre's forerunner. In fairness the guy in this instance seemed to be following the evidence available at the time and not a religious agenda. It's not like those that take the scripture and say this is how it is, thus the scientific explanation must accord with it, hence any explanation which contradicts must be wrong. The only way he could have possibly avoided any suggestion of doctrinal motivation would be by coming up with something completely different and contrary to the evidence to hand; even then there could probably be some vague link to doctrine found whatever was proposed. As he did not try and make the theory accord with the rest of the creation myth, the scripture story was not paramount.

He may have thought that his deity caused it, but it would appear that he followed the science first in this matter.