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"I rule!"

I have written an essay for English which I had 4 weeks to do in 5 hours...

The Catcher in the Rye, 1659 words of pure genius.

Now I think I might be able to get to sleep now.

Night Night

11am tommorrow spare a thought for me... Maths test :(

I can remember that stuff, its the endless equations and calculus that mess me up.

Mass exerts a gravitational force,
gravity can bend the path of light (as seen with black holes and experiments at eclipses),
so the theory goes that it is not the light that is bent, but that space has been bent (as with a black hole all the mass is concentrated into one spot the singularity and space is messed up there),
so it is theorised that you can bend space to get to another place quicker.
example: the distance from one side of a piece of paper to the other- the distance becomes smaller if you fold the paper until it is nearly touching and so you can get to the other place quicker. same basic theory holds with the bending of space.

ah no, ignore the first bit. I do see what you mean. I missed the 2D/3d interaction.

Yes that makes sense

So then, explain Einstein's idea of bending space to render interplanetary travel possible.. I'm getting into the space debate theories now..

and we know everything is moving apart because we can detect the redshift in the light coming from distant stars.
Where as the travel away from us their light spectrums wavelength is........ ohh I've gone cross eyed.

Yes I see where you are coming from. But surely he balloon is expanding into the air that surrounds it.. I find this concept completely mind-numbing. Is there actually a conceivable end to the universe. I accept that there might be a finite edge, but as it is scientifically impossible for us to ever reach that edge I don't suppose it matters.

I dropped Physics after GCSE, wasn't bad at it, I just preferred English-y subjects. But anyway, one thing I do remember from physics was my teacher saying that perhaps there were lots of big bangs, and lots of universes expanding and contracting. Is that right? Well, not right, but is it a scientist-approved idea or not?

misterhappy wrote:
> My question is, what exactly is the universe expanding into?

I can accept
> that it can expand, and even contract again, but what surrounds the outside of
> the universe, into which it expands?

The universe surrounds itself.

If you start off at Earth, and go in a perfextly straight line, you'll eventually come back to Earth.

Think of it like the surface of a balloon. Imagine our 3D space is mapped onto the 2D balloon surface. There is no 'outside', if you can only move along that surface. the expansion is the equivalent of the balloon being blown up. Everything gets further apart, but we don't expand into anything.

All the detectable mass in the universe, that we know of (ie, just the stars, basically) makes up 1% of the mass needed for a big crunch.

So we're a *litte* under, according to what we've found so far. But the fact we're not sure if there's enough out there for another 99%, shows how little we know of the universe.

I like making up crazy theories on the big bang, unfortunately I can't think of one right now

My question is, what exactly is the universe expanding into?

I can accept that it can expand, and even contract again, but what surrounds the outside of the universe, into which it expands?

hehe.

There are lots of theories about the universe... like, for example, that we are in an endless cycle of 'big bangs' and 'big crunches'.

Another is that our universe sprang from a black hole in another universe, which in turn could have sprung from a black hole in another universe....