h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

If the Universe "hits a wall, " then it will turn back on itself.

but there is no wall, nor can there be.
Although there may be other limitations to expansion.

We wont know if there is a wall untill we hit it.

no, but we can work out that it is extremely unlikely and doesn't fit in with current theories and knowledge of multidimensional space (although space is the wrong word I feel).

what other word is there?

Having just finished "The Restaurant at the End of the Universe" I loved Ford Prefect's drunken explanation of the beginning of the universe - Sitting at Milliways trying to get the others to imagine a conical ebony bath filled with sugar twirling out of the plughole - filmed and then played backwards. Wonderful.

I assume the theory that the universe is expanding is simply because this is what happens with any explosion - it throws particles out. So why is it supposed to then contract on itself - surely it would just peter out and just ...float.

Somewhere over there in the very distant future a sad, lonely girl sat thinking. She had special quantum powers of beauty, imagination and zeal. Her name was Reality Effervescence, Real Essence for short. She let some thoughts escape once in the far distant future. They flew around, fluttered their wings and landed on a soft, supple cloud. Her butterfly thoughts manifested into a universe. This universe expanded into infinity with pieces of glitter and hunks of water mixed with blue and green. Real Essence was impressed, even though these were her thoughts, because other things began to appear. She saw Rough and Smooth moving left and right, over and under, and round and round. They didn’t stop once they started. They just kept on and on, forever and ever, unless she snapped them off, because she did have a mean streak. She combined Rough and Smooth with her thoughts and called them by her own name. People gave them so many names. They talked and talked about this, then and now.

I don't like to sound all clever, but here goes...
Life started simply as a war between matter and dark matter , when they touched each other, they just exploded. Didn't any of you see the story of Stephen Hawking?!

you are damn good at explantions!

I don't believe in the big (open speech marks) crunch (close speech marks) though I do believe in the BIG (open speechmarks) TEAR (comma) or RIP (closed speech marks) (open bracket) not Rest In Peace (close bracket.)
E=MC2. Do you know what it means? If you don't: E is energy, M is mass ans C is speed of light. Therefore the the energy of an standard apple (open bracket) 100grams (close bracket) is probably about [drumroll please...] about 100*(100,000mps*100,000mps)which is about 100,000,000,00. If you know, explain further why on earth I would want to know the energy of an apple...
I also know the answer to life, the universe and everything, and it isn't 42!

Am I a (open speech marks) (close speech marks)

EVIL_VOGON