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I Are displaced dark matter and curved spacetime same thing?

  1. Jun 5, 2018 #1
    If dark matter is a supersolid that fills 'empty' space and is displaced by visible matter, then is this the same notion as the spacetime fabric having mass and being curved by visible matter?
     
  2. jcsd
  3. Jun 5, 2018 #2

    Drakkith

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    This is not what dark matter is. The most plausible possibility currently is that dark matter is a form of matter that does not interact through 3 out of the 4 fundamental forces of nature, gravity being the exception. It would not be a supersolid and it does not fill empty space, nor is it displaced by normal matter. In fact, it simply passes right through normal matter!
     
  4. Jun 5, 2018 #3
    How sure are physicists that it passes right through visible matter?

    Dark matter halos may leave twinkling wake in galaxies

    If a galaxy is able to cause a wake in the dark matter, then isn't that evidence the visible matter is moving through and displacing the dark matter, analogous to the wake created by a boat?
     
  5. Jun 5, 2018 #4

    Drakkith

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    Very confident. Multiple pieces of evidence support it.

    No, because the dark matter isn't being displaced. It's being affected by the gravity of normal matter.

    I'm sorry I can't give more information, but I'm about to step out the door to go to a dental appointment. I'm sure someone else can expand on what I've said in the meantime. Good day!
     
  6. Jun 5, 2018 #5
    What evidence?

    Yet another WIMP detector has failed to turn up any evidence of WIMP dark matter.

    Dark Matter Hunt Fails to Find the Elusive Particles

    Isn't it at all possible that the notion of WIMPs is incorrect and that dark matter actually strongly interacts with visible matter?
     
  7. Jun 5, 2018 #6

    Dale

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    That is actually some of the evidence that supports the idea that it interacts only gravitationally. The WIMP idea is that dark matter interacts gravitationally and through the weak force. Failure to find such a weakly interacting particle is evidence supporting the idea that it interacts only gravitationally.

    That is certainly not the case. The WIMP notion may be incorrect, but if it is it is incorrect in the opposite direction of what you suggest. It would be ascribing too much interaction, as evidenced by the study you mentioned
     
  8. Jun 5, 2018 #7
    If a galaxy is capable of creating a wake in the dark matter then why can't dark matter interact strongly with visible matter? Why can't visible matter be moving through and displacing the dark matter? Why can't what is referred to as curved spacetime physically exist in nature as displaced dark matter?
     
  9. Jun 5, 2018 #8

    Drakkith

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    Because that doesn't match our observations and experiments or our theories on spacetime. The 'wake' is not a wake in the sense that something is physically displacing dark matter, it is the result of gravitational interactions between the dark matter and the normal matter passing through. And we know that dark matter can't interact strongly with visible matter because we don't observe any collisions, heating, clumping, or other effects that should happen if dark matter and normal matter strongly interacted.
     
  10. Jun 5, 2018 #9
    What if gravity is 'observing' the dark matter being displaced by the visible matter? What if dark matter is the medium that waves in a double-slit experiment? What if we are 'observing' the dark matter every time a double-slit experiment is performed? Couldn't we be observing evidence of dark matter all around us and just mistaking what is actually occurring physically in nature?
     
  11. Jun 5, 2018 #10

    Drakkith

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    The properties of dark matter are constrained by what we observe, and the evidence points to dark matter being some sort of weakly/non-interacting particle. There are other possibilities, but these are less supported by the available evidence and are considered less likely. Most of what you posted here is so far beyond what we observe and breaks so many physical theories that it almost certainly cannot be correct.
     
  12. Jun 5, 2018 #11
    Why does displaced dark matter being the physical manifestation of curved spacetime break stuff?
     
  13. Jun 5, 2018 #12

    Drakkith

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    Because there's no way for this to happen in General Relativity unless you just mean that the displacement is the result of gravitational interactions.
     
  14. Jun 5, 2018 #13

    Dale

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    If it takes a galactic sized object to make a wake then the interaction is definitely not strong. The EM interaction, for example, only takes a boat sized object to make a wake :smile: (or smaller)

    Do you have a reference for this or is it personal speculation.

    As you have posted several potentially speculative posts, please PM me a scientific reference before continuing this discussion.
     
    Last edited: Jun 5, 2018
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