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I Clarification of Higgs field, Higgs boson and gravitons

  1. Aug 17, 2016 #1
    since gravity under GR has unlimited range the graviton must be massless. since the graviton is massless, the higgs field does not couple to the graviton. If the higgs field did couple to gravitons, it would cause gravitons to have mass, contradicting observation.

    but the higgs field carries energy, and gravitons must couple to the higgs field but remain massless.

    the higgs boson then does not couple to gravitons. but since the higgs boson carries energy, then gravitons must couple to the higgs boson. is it possible the higgs boson mass of 126 gev is the result of higgs coupling to gravitons

    is this correct? so if gravitons couple to both the higgs field and higgs boson based on energy, why doesn't the gravitons gain mass?
     
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  3. Aug 18, 2016 #2

    Vanadium 50

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    No,

    Since this is an A-level thread, please write down a coupling between A and B that is not also a coupling from B to A.
     
  4. Aug 18, 2016 #3

    vanhees71

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    Hint: The source of the gravitational field in GR is not mass but energy, momentum, and stress (look up the Einstein equation).
     
  5. Aug 19, 2016 #4

    ChrisVer

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    This is not a general rule, since it depends on how you build the interaction... for example the gluons are massless (to our knowledge) but the strong force does not have an infinite range... that is because QCD is built as such.
    Gravitons are hypothetical particles and we don't have a theoretical framework (like we do for gravity through General Relativity) from which we can say things like "contradicting observation". In particular there are theories with massive gravitons. The point you read, even in wikipedia, is that if a massless spin-2 particle is found then it must be a graviton, not the other way around.

    who knows?
    if you say that gravitons allow particles to interact gravitationally, then the gravitons would couple to the Higgs boson.

    As I mentioned above, gravitons could be massive. Also it may not necessarily get its mass from the Higgs field.
     
  6. Aug 19, 2016 #5

    mfb

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    There are very tight upper limits on the possible masses of gravitons (those leading to the long-distance gravity), and good reasons to expect them to be exactly massless to produce GR in the classical limit. There could be additional massive gravitons.
     
  7. Aug 19, 2016 #6
    gluons don't couple to the Higgs. gravitons do.

    this post presumes gravitons, possibly from string-m-theory exist.
    string theory claim to fame is it is the only known framework that can incorporate gravitons and is the only known theory of QG that gives GR

    gravitons in string theory are massless spin-2 particles that couples to all forms of energy, including itself and to the higgs field and higgs boson.

    every elementary particle that couples to the higgs field acquires mass. higgs field carries energy. gravitons couple to the higgs field, acquiring mass. in GR gravity is infinite range.

    it seems that a massless graviton that couples to the higgs field contradicts observation.
     
    Last edited: Aug 19, 2016
  8. Aug 19, 2016 #7
    gravitons is QG, which is BSM which is where i originally posted this
     
  9. Aug 19, 2016 #8
    In the standard model, the electroweak gauge bosons acquire mass because portions of the Higgs field become a part of them. A massless spin 1 particle has two helicity states (-1 and +1), a massive spin 1 particle has three (-1, 0, +1), and in the standard model this extra state that the massive Ws and Zs possess, is nothing but one of the components of the Higgs field. "The Higgs boson" is actually the leftover part of the standard model Higgs field.

    A massless graviton has two helicity states (-2, +2), a massive graviton has five (-2, -1, 0, +1, +2). The standard model Higgs field does not have the right properties to supply the necessary extra states.
     
  10. Aug 20, 2016 #9
    a QG that is about gravitons, and higgs field does not interact with gravitons, why is the planck scale of any relevance to higgs hierarchy problem?
     
  11. Aug 20, 2016 #10

    ChrisVer

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    Because that's where (planck scale) we expect to find new physics if Standard Model is all there is. It is the natural cut-off energy scale of the theory (as SM is an effective field theory).
     
  12. Aug 20, 2016 #11
    i understand there are various proposals for new physics. but if the only new physics are higher energy gravitons, how would that affect higgs?
     
  13. Aug 20, 2016 #12

    Vanadium 50

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    You don't actually have a graduate background in particle physics, do you? An A-level thread is going to go right over your head. What is the right level for this thread?
     
  14. Aug 20, 2016 #13
    Actually, it should, even in the absence of Higgs bosons, because of its nonzero vev.
    In their 2006 paper (see equation 14), Shaposhnikov and Wetterich cite claims that the effect is modest.
     
  15. Aug 20, 2016 #14
    how robust are his results? if true, are there any particles heavier than top quark, i.e susy partners ?
     
  16. Aug 22, 2016 #15
    Those questions appear to have no authoritative answers yet. They are a research opportunity.
     
  17. Aug 28, 2016 #16

    haushofer

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    How about introducing (an) extra Higgs doublet? Would this give something consistent? You would need three electrically neutral Higgs components, I suppose, so at least two extra Higgs doublets, right?

    As I understand this thread, the (necessary) coupling of the graviton to the vev of the Higgs does not necessarily lead to a mass term for the graviton? I never really thought about this, it's a good question.
     
  18. Aug 28, 2016 #17
    The premise is not necessarily correct. Higgs field CAN carry energy, depending on its configuration. Just as electron field can carry energy, but in some configurations (zero field) it does not.

    It is not a given that Higgs field in its VEV state has nonzero energy.
     
  19. Aug 28, 2016 #18

    Vanadium 50

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    What? It's 246 GeV!
     
  20. Aug 28, 2016 #19

    awww thx u :)

    yes that's right. since gravitons couple to the higgs, it should lead to a mass term for the graviton, giving gravitons mass, which contradicts the idea it is massless and has unlimited range.

    i originally posted this in bsm since it is really about qg and higgs

    btw sabine i have a thread in bsm on ur paper on lqg dark matter
     
  21. Aug 28, 2016 #20

    Haelfix

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    Linearized diffeomorphism invariance forbids a mass term, in a similar way that U(1) gauge invariance forbids a photon mass term. You are free to break the symmetry (as an axiom) if you wish, but then you will have to do work to show that you recover the successful predictions of ordinary GR. It is quite difficult to do this, as decades of work on massive gravity can attest too.
     
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