Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

I Does gravity just emerge out of all the quantum fields?

  1. Jan 8, 2018 #1
    Most research into quantum-gravity is looking for a specific particle, the graviton, to represent the gravitational force at a quantum level. But they also acknowledge that it might be impossible to find the graviton particle, because gravity is so weak. Now, is it possible that we're looking at this all wrong, and it's not impossible to find the graviton because it's so weak, but because it doesn't exist at all?

    Quantum Field Theory tells us that all of spacetime is made up of at least 17 different energy fields (represented by the 17 particles of the Standard Model), more if you split up all of the properties of these particles. So it is possible that gravity is just how spacetime reacts to the presence of all of those different types of energy in the same place, but does not itself constitute a real field? In other words, is gravity just the amalgamated field of all of these other fields?
     
  2. jcsd
  3. Jan 8, 2018 #2

    ohwilleke

    User Avatar
    Gold Member

    Basically no.

    Verlinde sought to reproduce the successes of other modified gravity theories in a variant of his entropy based gravity theories called "emergent gravity" which arises from quantum entanglement.

    Unfortunately, "emergent gravity" doesn't reproduce the observed data.



    Federico Lelli, Stacy S. McGaugh, and James M. Schombert "Testing Verlinde's Emergent Gravity with the Radial Acceleration Relation"(February 14, 2017).

    Another study looking at a different set of data with different investigators reaches basically the same conclusion.



    Aurelien Hees, Benoit Famaey, and Gianfraco Bertone, Emergent gravity in galaxies and in the Solar System (February 14, 2017).

    See also here.

    Also, keep in mind that the strong force and weak force operate at only very short ranges, and that particles, as their names suggest, are extremely localized. This leaves electromagnetism and perhaps the Higgs field as the only long range fields in the SM and neither is consistent with observed gravity.
     
  4. Jan 9, 2018 #3
    I didn't read Verlinde's work in any detail, just what was written in the popular press. Did his work refer to a graviton?
     
  5. Jan 10, 2018 #4
    By the definition of what "field" is, the metric tensor is a field: it assigns a value to every point of spacetime.
     
  6. Jan 10, 2018 #5

    ohwilleke

    User Avatar
    Gold Member

    No. He argued that quantum entanglement of particles at great distances from each other was a cause of gravity. Feel free to read his linked paper.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted