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zrice03
2003-Sep-28, 01:01 AM
I just had a thought. What if, instead of the universe expanding and accelerating, we are instead shrinking and accelerating?

Before you call me a moron, bear with me. I was reading the book The Elegant Universe by Brian Greene. In it he says in relation to a Garden-hose(cylindrical) universe, "String theory claims that all physical processes in the Garden-hose universe in which the radius of the circular dimension is shorter than the Planck length and is decreasing are absolutely identical to physical processes in which the circular dimension is longer than the Planck length and increasing!" Basically this means that nothing can get smaller than the Planck length(being about 10^-33 cm), and that going smaller will look like getting bigger.

My thought is that if our universe is actually smaller than the Planck length, it could be accelerating inward, making it look like it is actually accelerating outward.

To me, my idea is a bit more palpable than having some sort of cosmological constant. Instead of having a force that repulses and gets stronger as things get farther apart, it is simply that a more familiar force (like some exotic form of gravity), is just pulling everything together. Also the apparent size of the universe could be inversely related to the ratio of the the radius of the universe and the Planck length, so the real size could be about 1.3 x 10^-93 cm, if we assume an apparent radius of 13.7 billion light-years for the universe.

This is just an idea, not a hypothesis, and definitely not a theory. I would like feedback from anyone who is more knowledgable about these sorts of things.

Pinemarten
2003-Sep-28, 03:57 AM
Wait for a k........

I kind of agree the theory.
We write conclusions based on observations. As the observations change, we re-write the conclusions.
This is normal science.
I believe we tend to 'hold on' to some conclusions for a little too long.
We may be just too (?) to adapt to new ideas.

zrice03
2003-Sep-28, 04:06 AM
oh, if anyone was looking, the quote is on p.239, paragraph 2.

wedgebert
2003-Sep-28, 05:26 AM
Except our universe is larger than a planck length.

Well, at least OUR univere's Planck Length at least.

Rich
2003-Sep-28, 08:11 AM
Hey, no fair! You can't steal theCastanza Effect (www.badastronomy.com/phpBB/viewtopic.php?t=8178) from me and start a whole new thread! [-X

Pinemarten
2003-Sep-28, 01:22 PM
I should mind my manners.
Welcome to the board zrice03.
I see you and I are the only ones interested in discussing new ideas.

zrice03
2003-Sep-28, 09:49 PM
Hey, no fair! You can't steal theCastanza Effect (www.badastronomy.com/phpBB/viewtopic.php?t=8178) from me and start a whole new thread! [-X

um...I read your other post and it seems to me that we are discussing two different things. In mine, for example, the Planck length is fixed.

The thing is, all evidence points to a universe that is expanding and accelerating. I direct you to Astronomy magazine's article Do You Believe in the Big Bang?, December 2002 p.34. If you don't have it, I'm sure there are numerous sources you could look to verify that(ask Phil?).

I'm just extrapolating string theory's prediction that anything happening at smaller than Planck length will appear to be identical to things happening at larger than Planck length. You see, I'm not even trying to peddle this as a theory. I'm basically just thinking out loud and seeing what other people think, as opposed to you who seem to whole-heartedly believe in your hypothesis.

Rich
2003-Sep-29, 04:36 AM
It's ok. I was just playing with you anyway... And yes, welcome to the boards!

peter channon
2003-Sep-29, 05:24 PM
Hi zrice03.....

Thats one hell of a book and i have read it twice. It really deals with the most amazing aspects of the physical universe. I dont claim to understand it fully though but then maybe no-one does...
The thing is I am not sure Greene meant it quite as you have put it.

Greene is referring to 'the big crunch'.
Is he not saying that as a curled up dimension shrinks in size to that of the planck length then any further reduction will appear mathematically exactly as that for an expanding dimension greater than the planck length. String theory is predicting that the dimension can shrink down to the planck length but then any further shrinking actually results in expansion.

Make sense, probably not...oh well back to the book again.

Pete

zrice03
2003-Sep-30, 12:37 AM
Your probably right anyway. What happened was that right after I read that part(literally seconds) this idea burst into my head. Now that I think about it some more, it seems more and more unlikely. I suppose crossing the Planck length would be light trying to cross the light barrier, huh? Anyway, I'm re-reading the book now and trying to absorb every little detail I can.

Rich
2003-Sep-30, 04:44 AM
Oh and FYI - Elegant Universe is coming to a television near you soon.

Elegant Universe (http://www.msnbc.com/news/964547.asp?0cv=CB20)

peter channon
2003-Sep-30, 11:58 AM
I am currently reading somewhere in the last quarter of the book right now. Ten spacial dimensions! - freaky stuff.

Pete

kanon14
2003-Sep-30, 10:43 PM
Oh and FYI - Elegant Universe is coming to a television near you soon.

Elegant Universe (http://www.msnbc.com/news/964547.asp?0cv=CB20)

is it possible to watch it in canada??

zrice03
2003-Oct-01, 04:40 AM
Cool! I am definitely going to be watching it!

peter channon
2003-Oct-02, 03:45 PM
Damn...does that mean i cant see it in lill old England. Someones gotta send me a copy of that. Anyone with a DVD burner, please.

Pete

peter channon
2003-Oct-02, 03:49 PM
Hey is it just me or does anyone else think Brian Greene looks just like Fox Mulder.

Pete

zrice03
2003-Oct-03, 05:02 AM
Hey.......he does! Kind of a more pointy headed Fox Mulder.