Universe -- open or closed?

[HombrePequeno]

<< The latest, best scientific theory says that it is open. Here is a primer on cosmology today. >>



That deals with a different type of 'open.' He's asking us whether we thing the universe is finite or infinite. When scientists refer to the terms open or closed they're talking aboot if the universe will expand forever or eventually go into a Big Crunch. Yes new evidence does support that the universe will expand forever and eventually freeze.

 

[Mo0o]

what wrong with it being infinite. the number line is infinitly long, you uncomfortable with that?

 

[dman]

OK, so, if we pretend we can't fly, and we travel in a straight line on earth (which is really a curve) and end back a the same point... there's still something ABOVE us we just can't get there.

So, consider then space is curved. We fly away from earth and we go in a straight line away from it, and eventually we are back at earth. Then what is above the curve of space? Just because we can't get there doesn't mean it isn't there. I still think it's infinite.

 

[Haircut]

There is something above us because we are three dimensional creatures, if we existed on the surface of the earth in two dimensions then there would be no "up" we just couldn't imagine it.
In the same way we cannot imagine a fourth dimension (In 4D two planes intersect at a single point, try as hard as you like you cannot picture this.) to us there are three dimensions and that is all we can perceive.

 

[HombrePequeno]

<< OK, so, if we pretend we can't fly, and we travel in a straight line on earth (which is really a curve) and end back a the same point... there's still something ABOVE us. >>



Okay, think of yourself as a bacteria in a hamsterball or something. You start one place and go 'straight' but you end up back where you started.

Edit: Haircut's description is way more accurate.

 

[GigaCluster]

<< If we could travel far enough in our universe I think that we will eventually get back to the same point. >>



Ever seen the movie "THE CUBE"? Those people have wandered around the maze, only to wind up right where they started. If you haven't seen the movie, watch it. It's quite original and memorable.

I'm sure that someday (maybe centuries from now) our technology will be good enough to send an unmanned spaceship to go in some direction away from Earth, maintaining radio contact. Imagine how funny (yeah, hilarious) it would be if the spaceship eventually came back to us.

 

[ViperMagic]

Imagine pre-big bang. Nothingness. THERE IS NOTHING. Anywhere. Nothing. At all.

 

[GigaCluster]

<< Imagine pre-big bang. Nothingness. THERE IS NOTHING. Anywhere. Nothing. At all. >>



If there's NOTHING, anywhere, NOTHING AT ALL, from where would the universe appear?

 

[FelixDeCat]

Universe -- open or closed?


OPEN : M-F 7:00-9:00
SAT 10:00-?
SUN closed

 

[wviperw]

I don't think our minds can currently comprehend infinity. Here is one of my theories though... (prabably scientifically wrong but... )

The universe is expanding. What defines universe? Where light has reached right? So that would mean the universe is expanding at the speed of light. Meaning it DOES have a finite range. Yet, since we can't go faster than light(going by relativity), we will always be contained in the universe. Thus, light is the ultimate limit. eh?