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I Relation between spacetime distortion and light

  1. Sep 29, 2016 #1
    Recently, I was thinking about the nature of reciprocity in some cases of natural phenomenon, for example, Newtons Thrid Law of Motion, or, Faraday's Law of Induction.

    Considering that spacetime distortion, due to a gravity field, leads to a change in the light path, or, a change in light velocity, when observed from a region with diferent spacetime metric.

    Would a induced change in light velocity, induce a distorion in spacetime (to keep c constant at local reference), thus, generating gravity?

    And, lets consider that the propagation of the light (in vacuum) would be distorted (or have its aparent velocity changed) by some hypothetical advanced technology.

    It's the opposite direction of:
    Mass > Gravity > Spacetime distortion > Light distortion.
    Where, a induced light distortion would create:
    Light distortion > Spacetime distortion > Gravity

    Note that the spacetime warp would happen because c must be constant.

    Is this idea consistent? Is there any current model describing this?
    Last edited: Sep 29, 2016
  2. jcsd
  3. Sep 29, 2016 #2


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    How would you induce a change in the velocity of light? In what sense do you even MEAN a change in the velocity of light?
  4. Sep 29, 2016 #3
    I do not know, hence the "hypothetical advanced technology".. Like a closed system, or a "dark box" filled with vacuum, that somehow manages to change the apparent c for a observer outside the "dark box".



    Look at the image above, and consider that you, as a observer, is sitting outside the compressed spacetime region, you would notice the light moving slower inside that region, but, since the light is propagating in a space region where the metric is smaller, c would still be 299,798,452 m/s. In the sense that for an observer inside the compressed spacetime region, the velocity of the light would be normal.

    The question here is, since gravity (spacetime distortion) cause light to warp, would a warped light (due to a hypotetical, and very advanced device) cause the spacetime to warp, and generate a gravity field?

    Maybe this is too much of a philosofical question rather than only an physical one. But hey, philosophy and science is quite the same, depending on your perspective ;)

    I'm asking this, to get answers from other people, that may have a different understanding, from a different perspective.

    And maybe, start to develop a mathematical model for this.

    ( sorry, my english is very bad :/ )
  5. Sep 29, 2016 #4


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    You are asking "if the laws of physics do not apply, what would the laws of physics say about <insert nonsense of your choice". Do you see how that is not going to work?
  6. Sep 29, 2016 #5
    phinds, thank you for your answers.

    Laws of physics cannot be considered as absolute truth, since it's just a mathematical model and a logic way of abstracting some phenomena. It is still truth, but not the absolute thuth, can you understand this? (and yet, it is thuth only until it is proved wrong or incomplete)

    What I'm asking is very theoretical, that is why I've posted here in the Beyond the Standart Model section.

    I cannot prove you that light propagation can be warped, thus, warping spacetime (yet, we know that spacetime can be warped, thus, warping light). Can you prove me that it cannot? If yes, please, do it.

    ... Well, think in a device that can change the energy density of the vacuum, or the electric permissivity and magnetic permeability (the elastic constants of spacetime that defines c), please, prove that it cannot be done.

    I am not saying that what I said is true, I cannot confirm if my statement is true or false, it is false, prove it.

    Remember, "Beyond the Standart Model", "Theoretical Physics", everything is possible, until proven wrong.
  7. Sep 29, 2016 #6


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    Yes, I understand your point, but "beyond the standard model" on this forum, is not intended to include speculation that is outside mainstream media. You need to read the forum rules. Failure to do so risks getting warned by a moderator.

    If you wish to speculate beyond peer-reviewed physics, there are forums on the internet where you can do so but this isn't one of them.
  8. Sep 29, 2016 #7
    Oh, I'm very sorry for that. I got it wrong.

    I think this topic needs to be closed.

    Thank you for warning me about this.
  9. Sep 29, 2016 #8


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    No problem. This is a great forum but it's for main-stream physics.
  10. Sep 29, 2016 #9


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    No worries. If you feel like discussing mainstream science, feel free to stick around. If not, there are other places online that would be happy to have you, as Phind's mentioned.

    Thread locked.
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