Thread: The shape ot the universe

How can we ever ascertain the exact shape of our universe?

we can't although I've seen a recent Astronomy magazine that describes what the shape of the Universe may be according to string theory. They had a picture on it that looked more or less like a blob with various offshoots coming off it.

I recently saw a program on string theory and the talk of the possiblity of the 11 dimentions, but what id like to know is how people can base theories of other dimentions and the other universe when no can accurately put a shape to our own universe? I dont know enough about the topic as Im just a student studying in construction but the idea of the shape of our universe constantly plagues me.

First off, one should move away fro trying to think of the universe as having a shape in the normal sense of the word. If you hold a ball in your hand, you can see its shape only as a result of the existence of an area that is not the ball. That is, it requires an edge, as it is this edge that gives it its shape. When thinking about the universe, as described by current theory, there is no "outside" of the universe, not even emptiness (if you can make sense of that :? ). Instead, the universe behaves almost like being inside a black hole, in that when you leave earth in a straight path (at faster than light speeds), you would eventually end up back at the earth as a result of the subtle curvature of the space-time fabric. I guess if you started trips in different directions, you might eventually notice that the round trips take a different amount of time in different directions (so you traveled farther). When you put all of your aquired data together, you might then be able to see some form. The thing is that you could do this experiment from anywhere within the universe and come to the same result, weird huh? :wink:

wow, ive never looked at it like that. but i still feel it doesnt answer what im trying to think out. Your explaination as u said was based on a theory that if u travel in a straight line from earth you ll eventually reach earth again, so, if dats true, one can deduct that the universe is just like the ball u told me bout, round??? but as no one has ever done that journey its still a theory. so could it still be dat dere is a definte EDGE to our universe or am i just tinking like columbus's sceptics of old???

There are some theories that provide for an edge of sorts, where the edge is defined as the place all matter stops and where space-time itself is infinite. These theories have been discarded mostly though, as they do not account for nearly as many observed facts as the big bang theory does. One of these observations is the fact that space is expanding. So if you "reverse the clock", all matter (and indeed space itself)in the universe was once concentrated in a very small area. That is, an area as I described in my previous post as containing everything (including space-time) with no "outside" to it, only this one was maybe a singularity (an object of infinite density; zero dimensions).

PS: I expect Cosmo will post a reply shortly, but remember that he is not expressing the commonly held consensus. :wink:

Tanks for sharing your thoughts, its highly intresting, another theory so. we all agree on the big bang. matter from noting etc etc. so if the particle generator in cern can provide some enlightenment on the whole matter from noting, via some kind of experment, my tinking is that if our universe started with a big bang, then could it be possible that our universe is an experiment, of sorts. thinking outside the box, could you say that our universe is so large relevant to us as human beings, but how relevant is it to the size of whats beyond it?

thinking outside the box, could you say that our universe is so large relevant to us as human beings, but how relevant is it to the size of whats beyond it?

Well, the big bang theory excludes the possibility of the existence of a "beyond". If indeed the universe is infinite, as suggested by less well supported theories, that would certainly put our little observable universe to shame. :wink:

how do we know that noting existed before BB? i was reading other post and people were talking bout stuff before the BB and talk of matter being created 3 mins after BB and so on, i understand the idea of matter developing over time to form what is now, but i cant grasp the idea that the big bang JUST happened, and what was needed to fuel a Big Bang.

could m-theory help in this question?

Ive havent heard anything about m-theory, what does that say? I still belive dat the universe is relevant to the size of us and that for us to gauge the space that we exist in we must belive that our universe is apart of someting else, and is the size of something relevant outside our universe.

Its a saddle shape at the moment.

Care to provide some support for that statement?

Originally Posted by KALSTER

thinking outside the box, could you say that our universe is so large relevant to us as human beings, but how relevant is it to the size of whats beyond it?

Well, the big bang theory excludes the possibility of the existence of a "beyond". If indeed the universe is infinite, as suggested by less well supported theories, that would certainly put our little observable universe to shame. :wink:

I believe in a finite universe theory but I also believe the expansion of the universe to have infinite capability. If this is true, would it also be true to say classifying the universe as finite is only a technicality?

the m-theory suggests that strings (from string theory) if given a great amount of energy can expand into disks (called a brain) even possibley to the size of a universe and m-theory suggests that we could be living inside one of the brians and that theres other brain universes around us which collide into each other over billions of years resulting in many big bangs
heres a link i found to explain more
http://en.wikipedia.org/wiki/M-theory

Originally Posted by serpicojr

Care to provide some support for that statement?

Yes.

Present it.

It has been speculated that the universe is like a balloon. You could take a marker and put dots on the balloon to represent say the galaxies. As you blow up the balloon the dots not only move away from one another but they also grow in size.

My problem with this theory is that it ignores what is outside of the balloon and, moreso, what is inside of the balloon.