# Gnawing questions about the Edge of our Universe

## Main Question or Discussion Point

I've been mauling some questions about the end/edge of our universe in my head over the last couple hours, and Google is soooo inundated with useless pages. So I figured I'd come here to get some theories.
Sorry if I ask any dumb questions or posted this in the wrong thread. To Mod- I will move & delete if possible.

I understand that any information on this topic is speculative and I welcome all answers.

*It= The edge/end of the universe. **Edge just symbolizes the farthest part of our universe, like I'm there touching it (To clarify)

1.Is it a boundary (cross if you dare type deal)?
1a.Or is it a wall?

2.Is it hot?
2a.Cold?
2b.Or neither?

3.Could I touch it (if I was at the wall)?
3a.What would it feel like?
3b.Would it be the smoothest object ever?

4.Is the inner wall positively charged (to push it further out), with the outer side being negatively charged (to pull it further out)?
4a.Vice versa?
4b.Or neither?

5.Would it have a definable color?
5a.If so, would it be the purest/deepest black (for examples sake) possible?

6.Could matter even touch it (since it was the first one out of the gate)?
6a.If matter could touch/interact with it, would the energy be absorbed and redistributed along the edges of the universe like a wave rippling out along the wall from one end to the other indefinitely until the energy acquired at impact slowly "leached" back into the universe (negative A's impact energy flowing along the universes wall to negative Z, and positive A's impact energy flowing along the universes wall to positive Z)?
6b.Or, would the impact energy be reflected back into the universe relative to it's angle of impact?

7.Would the outside of the universe resemble a solid wall of matter (infinite in size) that has yet to be given a value; since the universe hasn't expanded to encompass that space yet (For example- a hard drive with one folder written onto it, leaving the "blank/nil-valued" space there with one sole purpose, to handle the inevitability of new data)?
7a.Or is the universes size constant?

And my most crazy question,

8.Could the end/edge be a giant spherical data interpretation medium, with the inside and outside layers creating a medium capable of reading and/or recording data?
^^ ^^ ^^ ^^
Here's a link to PopSci where a new method of data recording uses heat instead of magnetic fields.

Sorry for any poor sentence structure in my post, I despise commas and periods

Thanks for taking a look

Live it, Learn it, Love it, Do it, Master it, Say BOO-YAH!

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tiny-tim
Homework Helper
the universe does not have an edge

either it is infinite, or it is joined-up (like a sphere)

see Is the universe finite, or is it infinite?, and the other forum faqs on cosmology at https://www.physicsforums.com/forumdisplay.php?f=206 [Broken]

Last edited by a moderator:
Chronos
Gold Member
We already reside at the most ancient point in the observable universe, and, it looks exactly the same in every direction - younger.

2.Is it hot?
2a.Cold?
2b.Or neither?

6.Could matter even touch it (since it was the first one out of the gate)?
6a.If matter could touch/interact with it, would the energy be absorbed and redistributed along the edges of the universe like a wave rippling out along the wall from one end to the other indefinitely until the energy acquired at impact slowly "leached" back into the universe (negative A's impact energy flowing along the universes wall to negative Z, and positive A's impact energy flowing along the universes wall to positive Z)?
6b.Or, would the impact energy be reflected back into the universe relative to it's angle of impact?

7.Would the outside of the universe resemble a solid wall of matter (infinite in size) that has yet to be given a value; since the universe hasn't expanded to encompass that space yet (For example- a hard drive with one folder written onto it, leaving the "blank/nil-valued" space there with one sole purpose, to handle the inevitability of new data)?
7a.Or is the universes size constant?

And my most crazy question,

8.Could the end/edge be a giant spherical data interpretation medium, with the inside and outside layers creating a medium capable of reading and/or recording data?
The important point was already made about the shape of the universe and how it is unbounded.

However I figured I could give you a bit of insight into the universe in other ways than you intended (not relating to the boundary) that your questions are sort of relevant to, loosely or not.

As established there is not 'it', but if you were not aware if we're talking about an arbitrarily chosen location of the universe, say, locally 1 cubed kilometers in size. There is a tremendous probability that it will be cold. Around 3 degrees above absolute zero in fact, which is the average temperature of the universe/the temperature of the vacuum of space. Because there is so much more empty space than there are stellar objects, a cubed kilometer will most likely land you in a cold region.

I like that you asked about how matter would react when interacting with the 'boundary' or 'wall', again bearing in mind such a place/thing does not exist. Along with the mentioned closed (like a 3 spatial dimensional sphere surface [yes this is hard, or impossible to mentally visualize this is normal]) or infinite (either negatively curved 3-spatial dimensional saddle like shaped or 3-spatial dimensional flat shaped) another solution is also believed to be possible. In fact I can use your boundary question as an analogy appropriately enough to demonstrate in a way that is easier to imagine/picture. Now this is STRICTLY for this analogy and not reflective of reality - say there WAS this boundary. And a tennis ball was flying towards it. One of the options you did not consider was that, like in the game of pacman the ball would hit the boundary, appear to go through it, while actually instantly coming out the other side.

This is the toroidal universe shape and that is the best way I could non-mathematically describe the idea of it really. And mathematically I wouldn't be very good at the description anyway! Maybe someone better educated on geometry can help me out a little here if I'm off-base but this would be a universe that curls/curves in such a way that means if you were to travel in the same direction straight forever, you could find yourself coming back to where you began. The same applies for the closed-universe model however in that you are more so following a circle/a loop. But remember, every location of the universe has equal claim to being the center, so there is not some specific location in which space folds in the necessarily way for this to occur. The shape is called a three-dimensional torus. This is definitely not among the favored models, though to my knowledge it is not regarded as crack pot or fringe cosmology either.

If you are truly asking this based on your own pondering about 'who knows what's possible, just throwing some wild ideas out there to see what sort of interesting insights/answers I get' which seems to be more or less what the other questions were roughly motivated by then it's funny you ask this if you've not heard even passingly of the holographic principal. Though the boundaries in question are more accurately described as horizons or volumes, (no this again does not suggest a bounded universe) you may find this article interesting http://en.wikipedia.org/wiki/Holographic_principle you should be able to make sense of some of what is said. Note though that unlike my other answers which are firmly grounded, this is something much, much, much, much more speculative and if you hear it discussed in a popular-science medium like it is something strongly supported by evidence or anything like that, like the talks of man-made worm hole creation for time travel, etc. while these are not things that everything we know in cosmology says to be wrong in the way that the universe having a boundary we know to be wrong, they are immensely speculative and very far from being well understood if that ever even occurs.

It is a very fascinating idea to me though, and your question is actually interestingly close in some ways conceptually.

Oh and I forgot a question, the one about universe constant size (no it is expanding) and if it hasn't yet reached the boundary, the universe is not expanding into empty space or into anything. The universe is the universe, and the distance between non-closely gravitationally bound bodies (for example a galaxy that is 5 billion light years away from another galaxy) is increasing constantly with time, and at an ever increasing rate.

Though technically I didn't answer a single one of your questions, I hope you found these could be related a bit to them but on scientific grounds and are interesting for you.

The important point was already made about the shape of the universe and how it is unbounded.

However I figured I could give you a bit of insight into the universe in other ways than you intended (not relating to the boundary) that your questions are sort of relevant to, loosely or not.

As established there is not 'it', but if you were not aware if we're talking about an arbitrarily chosen location of the universe, say, locally 1 cubed kilometers in size. There is a tremendous probability that it will be cold. Around 3 degrees above absolute zero in fact, which is the average temperature of the universe/the temperature of the vacuum of space. Because there is so much more empty space than there are stellar objects, a cubed kilometer will most likely land you in a cold region.

I like that you asked about how matter would react when interacting with the 'boundary' or 'wall', again bearing in mind such a place/thing does not exist. Along with the mentioned closed (like a 3 spatial dimensional sphere surface [yes this is hard, or impossible to mentally visualize this is normal]) or infinite (either negatively curved 3-spatial dimensional saddle like shaped or 3-spatial dimensional flat shaped) another solution is also believed to be possible. In fact I can use your boundary question as an analogy appropriately enough to demonstrate in a way that is easier to imagine/picture. Now this is STRICTLY for this analogy and not reflective of reality - say there WAS this boundary. And a tennis ball was flying towards it. One of the options you did not consider was that, like in the game of pacman the ball would hit the boundary, appear to go through it, while actually instantly coming out the other side.

This is the toroidal universe shape and that is the best way I could non-mathematically describe the idea of it really. And mathematically I wouldn't be very good at the description anyway! Maybe someone better educated on geometry can help me out a little here if I'm off-base but this would be a universe that curls/curves in such a way that means if you were to travel in the same direction straight forever, you could find yourself coming back to where you began. The same applies for the closed-universe model however in that you are more so following a circle/a loop. But remember, every location of the universe has equal claim to being the center, so there is not some specific location in which space folds in the necessarily way for this to occur. The shape is called a three-dimensional torus. This is definitely not among the favored models, though to my knowledge it is not regarded as crack pot or fringe cosmology either.

If you are truly asking this based on your own pondering about 'who knows what's possible, just throwing some wild ideas out there to see what sort of interesting insights/answers I get' which seems to be more or less what the other questions were roughly motivated by then it's funny you ask this if you've not heard even passingly of the holographic principal. Though the boundaries in question are more accurately described as horizons or volumes, (no this again does not suggest a bounded universe) you may find this article interesting http://en.wikipedia.org/wiki/Holographic_principle you should be able to make sense of some of what is said. Note though that unlike my other answers which are firmly grounded, this is something much, much, much, much more speculative and if you hear it discussed in a popular-science medium like it is something strongly supported by evidence or anything like that, like the talks of man-made worm hole creation for time travel, etc. while these are not things that everything we know in cosmology says to be wrong in the way that the universe having a boundary we know to be wrong, they are immensely speculative and very far from being well understood if that ever even occurs.

It is a very fascinating idea to me though, and your question is actually interestingly close in some ways conceptually.

Oh and I forgot a question, the one about universe constant size (no it is expanding) and if it hasn't yet reached the boundary, the universe is not expanding into empty space or into anything. The universe is the universe, and the distance between non-closely gravitationally bound bodies (for example a galaxy that is 5 billion light years away from another galaxy) is increasing constantly with time, and at an ever increasing rate.

Though technically I didn't answer a single one of your questions, I hope you found these could be related a bit to them but on scientific grounds and are interesting for you.
Thanks Tech. Sorry I had a long 45min reply+thanks, but lost it upon submission, plus I lost the pre-cursor to this message just now All I can say is, THANK YOU THANK YOU THANK YOU (for now). I will get back to you later today and this time I'm typing on Word b/c that's 3 post I've lost upon submission (This threads main post being the first) Sleepy time.

Many thanks. Until later today