walk up to the end?????

[sergey500]

Well like I said this is not certain area of science, but as I see it, no there is no end point. Unless you count the limitations of the universe itself.

What did you mean moving in same direction? There is no real directions space, no up or down, left or right. although it is 3D space. The most direction you will get is "If you're going in linear path, as now, you will need to at 90 degree angle on the next planet, then fly 1.3 light years and you will reach blue star, in that sector you should find giantic planet, that what you are looking for" or "At vector 23023 in sector 0023 of Milky way galaxy, you will find Earth (no it won't work, i just made those directions up". Well that as much directions you will get. It depends on what motion you're going in. Newton first law will make sure you stay in striaght line (stay away from planets). From there it just visuals. You know what? I just don't get you're question, rephrase it please. If you mean the universe itself, no we do not know if its moving, not to mention in a certain direction...unless you can give directions in nothingness. But then again, there is always the multiverse idea you might want to look into for the hell of it.

[trapit]

As u said "Newtons first law will make sure that we will move along a straight path" ,can we make sure that we dont trace a same portion of the universe again and again?By this i mean that:suppose we see a star say alpha centuri at the begining of the journey,now we travel for 20 months(earth time) or so and one fine moment we see the star alpha centuri on the left of us.This means that we covered the area once.Will this happen?
I just mean the motion of a human who started a journey to see the whole universe,not the motion of the universe itself.

[sergey500]

i STRONGLY doubt that can happen, but unless you falll into a wormhole and manage to get through before it closes, it might be possible you will end up in same spot. Or excessed speed of light, and by relativty (sp?) we can say time will rewind in a way, so you can pass the same point in those two ways. None of which has been done before...but then again, no one ever navigated the universe.

Well no, there IS a way that not so far fetched. If the universe is closed and if there is enough matter in the Universe, space may have enough positive curvature to bend right back on itself (a reason why it can be sphere). But if you can't exit the univrse into the nothingness/null space, you can probably glide on the sphere, since you will never find an edge. But since we are in 3-D space, a closed universe means curvaure into the fourth dimension, thus no center in our universe, it some what of a paradox. But what i am trying to say in a nutshell, is that if indeed the universe is sphere and no edges, and you can glide on end of it, then yes indeed you can circumnaviage the universe.

[brigade]

hai,
am a new member,just found the thread interesting.
I just am doubting that,why do we always go for three dimensional geometry to explain universe.Mordern physics says there are 11 dimensions(as to my knowledge).
We say null,becoz,the nullness we suppose is a nothingness in the three dimensional space.Cant there be a different meaning in another concept with more than 3-D.

[Tormod]

There is a lot of confusion in this thread.

3D geometry is perfectly applicable to practial things like how far is it from A to B on a flat surface (for example a map). 3D geometry was the only kind of geometry used up until maybe a century ago since it basically was the only geometry known (this is the simplified answer).

Multiple dimensions was something that came into play at a fairly recent time, say end of the 19th century. Einstein's relativity theory was not the first to involve multiple dimensions but I think we can safely say his theories made it obvious that 3D geometry could not explain everything.

There is no reason to use 11 dimensions, which comes from M-theory, or string theory, in everyday calculations when there are much simpler approaches. Multiple dimensions are used in higher math. String theory is an as of yet unproven theory with no predictions.

There is also no reason to assume that the universe is spherical. What we know (because we can see it) is that the *observable* universe is spherical, and we're at the smack bang middle of it, because it is defined by the light that has reached us since the big bang.

Sergey500 has some good replies and there are also lots of other threads here where dimensions, the shape of the universe, and infinity is being discuss. And it would definitely help to pick up a good book on cosmology - for example John Barrow's "The Constants of Nature" or "The Artful Universe".

[sergey500]

Well Tormod, I feel like i mentioned all that, but that is not of the problem. You said "and we're at the smack bang middle of it, because it is defined by the light that has reached us since the big bang." well i must disagree. You make it sound, or are making it sound, like we are at center of the universe. If you are right of wrong is not my problem, it is that you assume for what sounds like certainty that we are in center. That sounds somewhat arrogant, no offense, but it just reminds me of when we were in center of solar system, until the heliocentric idea game into view we all believed that we were at center, so I just want to point out, its not a good idea to assume the world rotates around ourselves only. You're explaintion to why we can be in the center, would work, but then again, light hits things at different times, what was reached first by the light of the big bang would probably be the closest thing to center, but we don't exacrtly know what that is, do we? We can't say that big bang happened in the solar system, it makes little sense Or I misinterpreted you're sentence. Or, better yet, I am too fatigued with dullness (too bored) at the moment to think of logical arguement.

[brigade]

Can we say that the center of the universe lies at the origin of big bang?

[sergey500]

Yes we can. That where it started it. Thats the the center.

[armofreek]

is it even possible to determine where we are in the universe? i mean, if we can't even figure out if the universe has an end, how can we say that we are in the middle? And if we are in the middle, "where the big bang happened," then i guess it would make sense that there is life flourishing on this planet, being the "oldest" piece of space... blahh blah yadah yadda

[lindagarrette]

Originally Posted by brigade

Can we say that the center of the universe lies at the origin of big bang?

Of course. When the BB occurred, that was the universe.