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A viewpoint.

  1. Jul 11, 2006 #1
    First of all I am not claiming that I have a new theory or something.What I am just saying is that I have another viewpoint of looking at the things which will follow.Before that,I request you all that if you read the post please leave a reply,may be a comment,a flaw that you find,some criticism,if you want you can put that I am a jerk but please discuss and guide.So here goes.

    When I first learnt that G relativity puts gravity as space-time geometry then my response was that other forces must also be space-time geometry as nature can't be biased to one force.That was just an intuition.No other reason for believing that.Then I came to know about kaluza-klain theory and representation of forces as geometry of higher dimensions.
    Now,what I feel is that if forces are space-time geometry,and force-fields contain energy then energy must also be space-time geometry.You may now say that energy is what causes space-time curvature,but what I say is that what if it's other way round?What if space-time curvature is energy as to me space-time is more fundamental than any thing else.
    I am not saying that whatever I have said is right,I am just saying that we should at least once look at the whole picture that way.
    Now if energy and mass are inter convertible,then,it can be said that mass is also just space-time geometry.These wrinkles in space-time are the soul reason of existence of forces,energy,matter and dark-matter.

    So gist of the story is that I think that every thing in this universe is nothing more than space-time geometry.

    Analysis and criticism of the above are highly requested.Please discuss and guide.

  2. jcsd
  3. Jul 11, 2006 #2
    It sounds interesting. Isnt spacetime dependent on the matter inside it, and without matter there would be no spacetime?
  4. Jul 12, 2006 #3

    Well,no.But,if you say that spacetime is dependent on matter and energy,then I will say yes.No doubt that two came into being simultaniously.Now,the question is which one is whose consequence?Is space-time due to energy,or,is it that we are viewing it from a totally different prospective.
  5. Jul 12, 2006 #4


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  6. Jul 12, 2006 #5

    This idea is not a strange idea, Einstein tried to unify electromagnetism and gravitomagnetism together (weak and strong forces have not been discovered at this time). Now, it is a goal to unify the four interaction (but there is the gravitation problem...).

    Using Classical Mecanics, gravitation field is caused by mass. But, as you said, since RR, we know that mass and energy are connected. This equivalence brings to Einstein equation, which make the connection between spacetime curvature and energy density. So, where there is energy, there is spacetime curvature as gravitation.

    There is a problem. Imagine a graviton, the hypothetical gravitation particle. This particle has an energy equal at E=hf if gravitomagnetic waves travel at c, so it curves spacetime, so there are other gravitomagnetic waves created which have energy ...

    Also, imagine an electric field. In this electric field, there is energy which curves spacetime and creates gravitomagnetic waves. If we can describe electric field as a spacetime curvature, does it means that where there is a spacetime curvature there is emission of gravitomagnetic and electromagnetic waves?

    I would say that spacetime isn't dependent of matter, but rather dependant of energy (energy could exist without mass, but not the contrary).

    It's a bit like Mach principle : imagine that you're alone in spacetime, nothing else around you. You start to turn around. Would it make sense to you? You would be turning around what? Nothing. So, how could you say that you're in rotation?

    If there is no energy, you would not be there to say that there is no energy and to say that spacetime still exist without energy ... :wink:
  7. Jul 13, 2006 #6
    I don't think so.Reason being,the form of energy present will depend on the exact geometry of space-time.So,if it's a field or a mass or what kind of field will depend on the geometry.Secondly,you have asked that where there is space-time curvature,is there an emission of EM or GM waves?Well,IMHO,we are looking it the otherway round as allready said in my first post.The phenomenan of emission is not due to curvature,it IS the curvature.
  8. Jul 13, 2006 #7
    Well there is absolutely nothing wrong with this idea.
    Note though that the notion of space-time geometry is simply a way to model reality, mathematical models of reality are not the same as reality. Even a die-hard Platonist would have to admit that. :smile:

    There is absolutely no reason why we could not do it with other forces as well, granted modeling discrete spaces and spaces that violate the locality principle is not something easy but certainly not impossible.
    Even in GR not everything is a-ok. For instance try to model the behaviour of a mass particle with a certain diameter in GR, it is next to impossible.

    The reason why it is not done for other forces is that the particle/wave model works just fine and I suppose if we were to model it like GR it would just be a lot harder. And the progress with regards to predictability is next to none. So why do it?
    Last edited: Jul 13, 2006
  9. Jul 13, 2006 #8
    I don't quite see how Wheeler's geometrodynamics is relevant to the original question. (By the way, the wikipedia article you've linked is an absolute mess, and doesn't actually have much correct to say about geometrodynamics.)
  10. Jul 13, 2006 #9
    Well according to inflation theory a pressure creates a gravitational field so it's not an unknown idea. This is based on the idea pressure is a form of energy and therefore has mass equivilence.
  11. Jul 13, 2006 #10


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    Admittedly, the wiki entry isn't the greatest... but it was easy to find with google and at least names some names which could be followed up if one is sufficiently interested.

    So, let's go to the original references. [I highlighted the relevant parts.]
    From Wheeler's 1962 Geometrodynamics, p. 225 (which I couldn't find on the web)
    [I see now that this is reprinted from "Classical physics as geometry", Annals of Physics, 2, 525-603 (1957) Annals of Physics, 2, 525-603 (1957) with this first line in the abstract:

    Since the OP said
    there seems to be a similarity that may be of interest to the OP.... IMHO.
    Last edited: Jul 13, 2006
  12. Jul 14, 2006 #11
    "Everything IS space time geometry ..."
    It is dangerous to say this. We, humans, have invented concepts (such as mass, energy, time, ..) for which we have some kind of feeling and therefore our physical laws, of which we are so fond of, are by no means absolute thruths. They are nothing more of a viewpoint of the world, which suits our purpose, nl. to understand the relation between things and phenomena. Space time geometry is also just an abstraction which seems to work well to understand things like graviatational time dilatation and many other things. So, we can never claim what nature actually IS, we can only present a particular way of describing it. If we look at a city (like Detroit) from out of a plane at some high distance above the city and we see all the nice structured streets, some clever physicist will say : "Oh look, a city IS actually a collection of one dimensional lines, crossing each other at right angles" and then he could go on and develop a lot of mathematical relations about it (compare to general relativity). Well, I would say that the city is more then a number of mathematical lines. The abstraction of making lines out of streets, may however be useful for some people, but it is just an abstraction of a very limited amount of the "real world". So, the space time geometry is also just a first order description of something much more complicated and much richer than we can imagine for the moment. So, let us always remain very humble and accept that we will always be able to grasp only an infinitesimal part of reality. Physicists who think that they can device "A Theory of Everything" are absolutely on the wrong track and should better be brought to a mental hospital.
  13. Jul 14, 2006 #12
    No they shouldn't.

    himura: I find myself attracted to geometrical concepts rather than for example messenger particles. But I think you go a step too far suggesting that energy is curvature. After all, the energy of a leaf spring is not the curvature. It's more like a measure of the action that caused the curvature, or the action that this curvature could cause.
  14. Jul 17, 2006 #13
    according to gr space-time can contain no radiation or matter but still have energy stored in its curvature. According to QM it is possible for random quantum fluctuations to spontaneously effect a negative or positive curvature within the metric. Einstein's conservation law is not violated because the stored energy creates a false vaccumm with a negative pressure that does work on itself.
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