What is there in nothing?
Did you ever wander what you will find if you go past the entire universe, beyond all the stars? What do you think will you find there? Don’t you think that is must end somewhere? What is there where it ends?
There is a spit in science that specifically deals with this. With other words: what is there in a vacuum? There is something. We just have to find it.
I think there is already a discussion on this topic somewhere but anyway. You can't get to the end of the universe, couse beyond the universe nothing exists not even laws of physics, biology... so presumably you will never reach the end of the universe since the gravity fields will keep you inside, its like an ant walking on a surface of a ball, he cant leave it and he certainly cant say where is the end. 
But i wouldn't worry what is there especially if we are not yet able even say what forms over 50% of the universe matter itself. 
| Wynand wrote: |
What is there in nothing?
Did you ever wander what you will find if you go past the entire universe, beyond all the stars? What do you think will you find there? Don’t you think that is must end somewhere? What is there where it ends?
There is a spit in science that specifically deals with this. With other words: what is there in a vacuum? There is something. We just have to find it. |
Nononono....wrong headed thinking here.
There is, of course, spacetime in a vacuum - spacetime being the combination of the 4 dimensions we are all familiar with - 3 spacial and one temporal. That is 'something' rather than nothing. Further, vacuum can spontaneously produce matter (sounds weird but its not really). Without getting too deep, imagine an electron and a positron - they combine to anihhilate each other of course, so the reverse can happen - vacuum can be considered as a sea of particles popping in and out of existence as they anihhilate and re-emerge (they are called virtual particles or vacuum fluctuations). You can imagine them another way by thinking about the uncertainty principle. 2 particles anihhilating to produce energy and vacuum are actually bound by quantuum physics to be a probability distribution and cannot be defined exactly because of uncertainty. A photon passing through a 'vacuum' can, therefore, interact to produce a positron and electron out of 'nothing'. It's deep physics but you could try looking up the Casimir effect if you are interested.
Anyway, the point is that vacuum is not 'nothing'. Nothing, in the sense you mean, is the complete absence of spacetime - no dimension and no time.
As for the 'edge' of the universe : it is currently thought that the universe is finite which might lead you to think you can go to the edge of it. Not necessarily so - if you imagine the 3 spacial dimensions as the skin of a balloon and then imagine a 4th spacial dimension as being the space inside the balloon curving the surface back on itself, you should be able to picture an infinite 3-D space with finite boundaries - eventually curving back on itself meaning no 'edge' exists. It has to be said that this is not currently the model thought to be correct. You have to bear in mind that 'common sense' is not much good when considering these issues since 'Common sense' is rarely either, and our normal experiences do not allow us to draw analogies and metaphors for complex topography since there is nothing in our experience that we can say it is 'like'.
In fact most analogies end up confusing more than clarifying. These concepts can only really be described adequately in mathematical terms because our natural language has no reference points to cling to....
Chris.Beyond the universe...well we probably will never know now. As we can tell, the universe is friggin huge. As to vacuum, I'll leave the quantum mechanics explanation to the guy above, I haven't really studied up on it yet
Hmmm....
Bikerman, you wanna make any clarifications about vacuums and space time at distances below the Planck distance? I've read bits and pieces, but only enough to pique my interest.
| HoboPelican wrote: |
Hmmm....
Bikerman, you wanna make any clarifications about vacuums and space time at distances below the Planck distance? I've read bits and pieces, but only enough to pique my interest. |
That's a very deep question and to do it justice I'm gonna have to take some time and read a bit more myself. I'm a generalist, not a physicist or cosmologist, so what I know is from my own interest, reading and chatting with scientists. What I do remember on this subject is there is some thought that expansion could actually 'increase' the plank distance and possibly render it 'sensible' in the sense that it could be experienced. At the moment the planck distance (10e-33) is possibly where the Higgs field kicks-in, according to old theory. Newer theory is different. Quantum gravity postulates that the 'graviton' will only have significant force at Planck distances (gravity being so weak) and Penrose thinks that at this scale the universe consists of gravitons interacting ('twisting' as he puts it) effectively meaning that the material universe would cancel down to the effect of gravitons twisting round each other and, even stranger, spacetime would not exist independently of this 'planck-scale' forces so the twister would effectively define where spacetime was and was not.
Recently there is another theory in this field which most people have heard of - String (superstring) theory. This posits that at the Planck scale spacetime consists of intertwining 'loops' a bit like a string vest, thus spacetime is effectively a string vest woven of tiny one-dimensional strings vibrating at different harmonics to produce the diffeent facets of mass/energy that we observe. This is very deep stuff, as I said, and I can only really skate the surface without doing some more reading. I think this is a reasonable amateur sketch of the situation but I hope no physicists are reading because they will surely find it simplistic and possibly reducto ad absurdum....
Cheers
Chris | Bikerman wrote: |
...even stranger, spacetime would not exist independently of this 'planck-scale' forces so the twister would effectively define where spacetime was and was not.
....
Cheers
Chris |
This break down (maybe a poor phraseology) of space-time is what I was curious about, expecially in terms of the topic here.
I really need to get motivated and do some serious reading on current string theory, but I do admit to being way out of my depth in this field. | HoboPelican wrote: |
| Bikerman wrote: | ...even stranger, spacetime would not exist independently of this 'planck-scale' forces so the twister would effectively define where spacetime was and was not.
....
Cheers
Chris |
This break down (maybe a poor phraseology) of space-time is what I was curious about, expecially in terms of the topic here.
I really need to get motivated and do some serious reading on current string theory, but I do admit to being way out of my depth in this field. |
Some good starting points I can recommend :-
Excellent Nova video series :
http://www.pbs.org/wgbh/nova/elegant/
Good Site on basic theory
http://www.superstringtheory.com/
Another excellent resource
http://www.sukidog.com/jpierre/strings/
Cheers
ChrisI simply will state that I believe that the thought of there being a size to the universe is complete dung stuff. I think that there is no truth in that, since nobody has ever gone out there and tested it. But no I know people can look at stars or see how dim a star is and calculate based on this its age.
But in reality who really knows, since I myself do not know I simply think that when you do have a chance at getting close to the "edge" there is a black hole or something that makes you think that it is never ending because when ever you get close it will just move you some where else in space. For all we know space is not a circle it could just be as well a square or a cillinder.
-RADON
| nodarn wrote: |
I simply will state that I believe that the thought of there being a size to the universe is complete dung stuff. I think that there is no truth in that, since nobody has ever gone out there and tested it. But no I know people can look at stars or see how dim a star is and calculate based on this its age.
But in reality who really knows, since I myself do not know I simply think that when you do have a chance at getting close to the "edge" there is a black hole or something that makes you think that it is never ending because when ever you get close it will just move you some where else in space. For all we know space is not a circle it could just be as well a square or a cillinder.
-RADON |
This is an example of the sort of thinking that sometimes makes me wonder about progress. Basically put it says I can't see it therefore it is wrong.
The fact that mathematically and physically the statement is valid is completely irrelevant because you don't see it.
As I have said before, in science not all opinions are equal
Chris
