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Space Creation

  1. Dec 9, 2008 #1
    All the theories of the universe’s origins that I have read discuss expanding matter and energy. As far as I know, it is assumed that this expansion created space. I have also read that the universe is continuing to expand, however, at a much less energetic pace. I am wondering if anyone has come up with a formula for the creation of space.

    I would think that if such a formula existed, space would have to be defined in terms of matter and energy. In the simplest form it would look something like this: matter X energy = space. Or velocity X matter = space. Clearly it would probably be a more complicated formula, perhaps velocity X matter would have to be squared or cubed.

    I am aware of the fact that this formula would cause many problems in the world of physics. We normally think of the universe as expanding “outward.” However, many theories of the universe dispel with the concept of “outward” and “inward.” It is comfortable to think of bodies that are the most distant from the “center” of the universe as traveling away from that center, pushing “out” the envelope space at the edge of the universe. Yet if the universe has no center or periphery, then the concept of energetic matter creating space could contradict many other assumptions of physics, such as our normal conception of gravity.

    If, for example, all points in the universe can be thought of as both the center and periphery, then all matter in motion would be traveling “outward” (as well as “inward”) and creating space. Planets revolving around the sun would be creating space that would contradict the understood laws of gravity, because one would have to factor into gravity’s equation the addition of space.

    Yet if space is not considered an expression of matter and energy, what is it considered? How do physicists account for its creation both at the beginning of things and now? Shouldn’t there be some formula that accounts not only for its existence but its continual creation?
     
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  3. Dec 9, 2008 #2

    George Jones

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    Actually, observations indicate that the expansion is now accelerating.
    Einstein's (set of differential) equation(s) from general relativity relates the (possibly changing in time) geometry of spacetime (including expansion) to the distribution and flow of matter and energy in the universe.

    Unfortunately, these suggestions are far too simplistic.

    As I said above, general relativity, Einstein's conception of gravity, accounts reasonably well for observations. To see how this all fits together, some knowledge of general relativity is required.
     
  4. Dec 9, 2008 #3
    Just to argue a different perspective: space creates matter and energy via vacuum fluctuations and the cosmological constant (vacuum energy). No space, no vacuum energy??? Just speculation here.

    As George posted, general relativity does a good job of explaining the large scale evolution of the universe, perhaps supplemented by inflation theory during the earliest moments. But all bets are off at the instant of creation if it was a big bang as neither GR nor quantum theory works. My understanding is that matter,space,time, and energy appear to be intrinsically related, but no one knows which is fundamental and which are emergent...which are cause and which are effect...what causes a "pop" from an apparent vacuum??

    Roger Penrose has a twistor theory which elegantly explains how quantum spacetime evolves from light!!!..Crazy huh??? But the theory is incomplete after more than 20 years work!!!!! A brief description is given in Lee Smolins recent book,THE TROUBLE WITH PHYSICS. Twister space asdescribed in Wikipedia is incomprehensible to me.
     
  5. Dec 9, 2008 #4
    If matter, energy, space and time are all of the same cloth, so to speak, all related, then wouldn't they all be expressions of one another? In other words, shouldn't there be some formula like E=MC squared, including all of these elements? Some combination of energy, matter and time should express space, and then the equation could be turned all ways, combinations of space, energy and time resulting in matter, etc?

    My thinking, which goes a little far afield, has to do with "inside" and "outside." If matter in motion through time results in space, in what pattern and direction is that space created? If the universe has no center and no periphery, then all motion is both outward (toward the periphery) as well as inward, and that should result in outward space (what we think of as space) and inward space, which I think of as anti-space. That could be the place, if you will, where anti-matter exists. It sounds off-the-wall, but it makes total sense to me. It would also explain how the universe could be created from nothing, if in fact everything in the universe has an anti-property that combined would equal nothing.

    Perhaps this is not new thought, but I haven't read about it anywhere.
     
  6. Dec 9, 2008 #5
    In regards to Einstein's General Theory of Relativity, I have a few questions. First, I can understand how bodies in motion can be attracted to one another by following the curvature in space created by mass. However, if I construct a thought problem in which the universe consists of ony two bodies that are absoultely still, I cannot understand what gives them the impetus to move toward one another, if gravity is only the result of space curvature caused by matter. I also am confused by string theories search for the graviton. Why are gravitons an issue if Einstein's general theory of relativity explains gravity? And if gravitons do exist, does that cancel out Einstein's theory of curved space, or do gravitons somehow work in harmony with curved space?

    I am also not aware if Einstein fully considering a universe that has no center and no periphery. I am not even sure if most phsycist's believe this, or if their theories reflect this notion, if they do believe it. But if one thinks of a universe without a center or a periphery, then all points become both the center and the periphery. All motion must therefore be in two directions, outward and inward. I wonder if this would make the question of space creation a very different issue than Einstein concieved of it.
     
  7. Dec 10, 2008 #6

    A.T.

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  8. Dec 10, 2008 #7

    George Jones

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    What causes the masses to move together in a similar situation in Newton's theory of gravity?
    It is thought that quantum theory is framework for the entire physical world, but right now, there is no accepted quantum theory of gravity. String theorists say that string theory does the job, while other physicists remain skeptical. In a quantum theory of gravity, it is expected that gravity is mediated by gravitons. This should work in harmony with curved space, just as the concept of photons works in harmony with the concept of electromagnetic radiation.
     
  9. Dec 10, 2008 #8

    George Jones

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    The theory remains incomplete after more than 50 years work. Penrose, who is now 77, writes in his essay in the book On Space and Time, "The theory was originated in the mid 1950s, but not published (and even then not in full detail) until Penrose (1971)."
     
  10. Dec 10, 2008 #9
    Both of the examples I was referred to, of an object in "free fall" moving straight ahead in the explanation of time warpage and the curvature of light caused by a warpage in space, assume that the mass is in motion and of course light by definition is in motion. I have not read of an example in which Einstein's theory of gravitational forces being caused by a warps in either space or time works on bodies that are not in motion. Of course this is an impossible experiment to prove since finding a "still" body not in motion is as difficult as finding a pure vaccuum. I have always thought that Newton's theory of gravity includes some mysterious "attraction," like magnetic attraction, and thus would work on a thought problem in which bodies are not in motion.
     
  11. Dec 10, 2008 #10

    A.T.

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    Then look again. In the first example given here the free falling body is initially at rest in space, and moves only along the time dimension. The key is that bodies at rest in space still "move" trough spacetime.
     
  12. Dec 10, 2008 #11
    String theory accidentally found the "graviton" when it was noted a spin two massless particle naturally emerged from the mathematics...originally designed I think to explain the strong force....
    Gravitons are a quantum (particle) theory of gravity...in contrast to Einsteins Field (smooth and coninuous) theory....neither works near singularities...black hole centers and big bang environments so something else is needed to "unify" them. Gravitons are an alternative view, a different perspective attempting to explain gravity. How they are related to Einsteins formulation is a major question in theoretical phyics.
     
  13. Dec 10, 2008 #12
    I think I generally understand the concept of gravitons and why string theorists are trying to come up with a unifying theory, but somehow I have missed the answer to the question of how movement through space occurs with Einstein's theory. I understand that both the "attached" clock and the "freefalling" clock move through time, but not through space. Are you saying that movement through time is equivalent to movement through spacetime? Going back to my thought problem about two bodies at rest in an empty universe, I can see how space exists between them, but without any motion I cannot see how time exists. Are you saying that the thought problem is an impossibility, and that a universe cannot exist (even for an instant) in which nothing is in motion because that would negate the concept of spacetime?
     
  14. Dec 10, 2008 #13
    I think I should try to explain a little better what I am thinking about when I talk about a positive universe and a negative universe. We know that the positive universe in which we exist is expanding. That would mean that a negative universe would be contracting. If, as was suggested, the universe came into existence out of a “vacuum,” which I tend to think of as nothing (and a vacuum is something in my mind), I think it is generally agreed that the universe in which we exist expanded at the Big Bang. I think it would make logical sense at any rate to play with the idea that a counter-force created a contracting universe. I conceive of it in the way that it is theorized that a particle and anti-particle can come into existence out of nothing on the event horizon of a black hole.

    Since our universe, the positive universe, continues to expand, the negative universe would also continue to contract. Initially this expansion and contraction emerged from a “central” point in space. However, if the universe is conceived of as having no center and no periphery, then that would mean that that ontological point is now every point in space, and both the expansion into “outer space” and the contraction into “inner space” continue at all points in the universe. For me it helps to think of the universe as a point (or singularity?) which has both exploded and imploded. When and if the Big Crunch occurs, then our positive universe will begin to contract and the negative universe will begin to expand until they once again become one big (or infinitesimal) nothing.

    I have read string theorists talk about added dimensions. If I remember correctly I think I’ve read the numbers nine and eleven total dimensions. If both an expanding and contracting universe existed, that could account for nine dimensions. The four we think of in the positive universe, four negative dimensions in the negative universe and a ninth dimension where these two universes meet (at every point in space). That meeting point could be thought of the way we think of a point on the event horizon of a black hole where a particle and anti-particle can come into existence out of nothing.

    Clearly this is just a way for me to try to conceive of a model of the universe I’ve read about in the various lay physics books I’ve read. I do not pretend to understand the mathematics of it all. Nor could I begin to explain what keeps the negative and positive universes separated, nor how all of this can be conceived of on a quantum level. It’s just a way for me to try to hold in my mind all of the strange and mind-blowing concepts I have read about.
     
  15. Dec 10, 2008 #14
    A stationary mass does curve spacetime but much of relativity is velocity based.

    You read a lot about motion in relativity because Einstein started thinking about light and decided everybody would observe light at a constant speed. There were inconsistences between Newtonian physics and the physics of the electromagnetic field. From all that he decided time and space must change as speed does, but light speed remains fixed.

    In general relativity Einstein realized that free falling frames with gravity are locally the same as extended inertial frames without gravity...his equivalence principle. So again his insights were based on motion, but not formulated exclusively for motion. Also, despite his best efforts, GR showed the universe to be "moving" as well despite his attempts to stablizie it via a cosmological constant. And finally, all planetary bodies are moving relative to each other as well as in their own orbits, there is no absolute stationary frame of reference, so physicsts naturally think of most large scale objects as in motion of one sort or another.
     
  16. Dec 10, 2008 #15
    I guess one of the directions I was heading with my thought problem had to do with mass in motion creating space. You are right that in the universe as it exists all mass is in motion, and I think it is generally assumed that if the universe's mass were to come to absolute rest, then the universe would implode due to gravitational forces. As the universe imploded I would have to think that space would also contract. Back to my thought problem, which is a way to think about the creation of space due to mass in motion, if two bodies were at absolute rest in an empty universe, would the space between them disappear? And if the space between them did disappear, would this be due to gravitational attraction such as stipulated by Newton and proponents of gravitons, or would the bodies be impelled into motion due to the curvature of space caused by the bodies' masses? If the bodies were attracted to one another due to the curvature of space (which makes no conceptual sense to me) would that not diminish as space diminished between the two bodies? What I am trying to do is reduce the concept of space and gravitational forces to its simplest principles so that I can understand how it fundamentally works, somewhat like looking at matter and time under the most extreme conditions of a black hole.
     
  17. Dec 10, 2008 #16
    One other thought I have about the curvature of space is that perhaps space is only curved by mass when it is in motion, and that mass at absolute rest would not curve space. And that the curvature of space due to mass in motion has to do with the creation of space due to mass in motion. And that takes me back to the question of the shape or pattern of space that is created by mass in motion. I don't think anyone can really deny that space would cease to exist if all motion ceased in the universe, so there has to be some connection between mass in motion and space. Back to my thought problem, if two bodies were at absolute rest in an empty universe, would they be attracted to one another due to gravitational forces, or would the space between them disappear because space must continually be recreated by mass in motion?
     
  18. Dec 10, 2008 #17

    A.T.

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    Just look at the diagram. The free falling object initially advances only trough time, but due to spacetime curvature it's direction gains a spatial component. The attached clocks obviously don't move trough space.
    Yes. Since time is one dimension of spacetime, advancing trough time implies advancing in spacetime.
    There are physical processes other than movement that indicate a flow of time (e.g. radioactive decay). In general: physical theories describe how our universe works, not some hypothetical universe without time.
     
    Last edited: Dec 10, 2008
  19. Dec 10, 2008 #18
    In regards to the clock diagram, isn't that an example of how a body in motion affects time? I still don't understand what impelled the body in the first place, and I'm not quite sure that diagram explains it. When I have read about one body's "attraction" to another due to warped space, the examples have always talked about the first body's motion being curved with space toward a second body, but never how the first body got moving in the first place. If one were to imagine that curved space impels one body toward another, then doesn't there have to be some sort of attractive force as in Newton's concept of gravity?
     
  20. Dec 10, 2008 #19

    A.T.

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    The two clocks show gravitational time dilation, which is not caused by motion. They are both stationary in space. But it also shows how a free falling body initially at rest in space, gains spatial velocity, by moving straight in spacetime.
    Everything advances trough spacetime in this model. The only thing that eventually changes is the direction in spacetime, what we perceive as acceleration in space.
    It's warped spacetime, not space. Get this right and you will understand the model.
     
  21. Dec 10, 2008 #20
    Thank you. I think I'm beginning to understand.
     
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