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Higgs boson and gravity

  1. Dec 13, 2011 #1
    okay, i am totally confused (again). i ihave a general understanding that the higgs mechanism is the effect which gives particles mass. the higgs mechanism is determined by the higgs field and mediated by the higgs boson. is that correct so far?

    now the HLC indicates that it has somehwat pinned down a potential mass for the higgs boson of around 120gev.

    so, a few questions (dont point me at wiki - i read it and cannot understand it...)

    1. if the higgs mechanism is what gives particles mass, how can the higgs boson have mass?

    2. since the higgs gives particles mass, and is basically a field, what is the relationship between the higgs field and the gravitational field?

    3. how can a new particle (higgs) give mass? ie, what is going on - from what i read, the actual boson is short lived, so how is it actually interacting with normal particles like electrons and quarks? is it virtual, like virtual photons? is it a "real" thing that pops into existence to interact and then disappears within the limits of HUP?

    i'll stop there for now - my brain is locked up.

  2. jcsd
  3. Dec 13, 2011 #2


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    The Higgs mechanism is what permits quarks, leptons and weak bosons to have rest mass in a way which does not violate gauge invariance. This does not mean mass in general, as mass can arise from other sources. The mass of nucleons, for example, comes almost entirely from the kinetic energy of the gluons within it, not the rest mass of the quarks.

    The rest mass is an effect produced by the Higgs field, which is universally everywhere and time independent. Not the Higgs boson which has a lifetime of perhaps 10-25 sec and is an excitation of the Higgs field. The Higgs boson has its own mass because of its nonlinear self-interaction.

    The gravitational field is not just coupled to mass, it's coupled to the stress-energy tensor which includes energy, momentum and stress. For example gravitation couples to photons, which have no mass.
  4. Dec 13, 2011 #3
    thanks bill - so does finding the higgs boson prove the existence of the higgs field? and how do they know that what they are looking at in the 125gev range is actually the higgs boson?

    are gluons inherent to the properties of quarks, or are gluons virtual like virtual photons?

    isnt the gravitational field created by mass? ie, if there were no mass in the universe, there would be no gravitational field, right? so, if the higgs field is what gives particles mass, there must be some direct correlation between higgs field and gravitational field, right?
  5. Dec 13, 2011 #4

    Wow, thanks for this post Bill_K. Very clear, appreciate the distinction you made between forms of mass.
  6. Dec 13, 2011 #5
    Why even call that mass and not instead energy?
  7. Dec 13, 2011 #6


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    Well, you might recall mass-energy equivalence relations. Aka E = mc2.
  8. Dec 14, 2011 #7


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    Because quarks bind together into nucleons, which then bind together into the nucleus of atoms. I would guess that it simply isn't practical to seperate a nucleon, nucleus, or atom into rest mass and mass due to the energy.
  9. Dec 14, 2011 #8
    Frankly I do not see the problem.
    I think it would make the confusion between mass and energy less.
  10. Dec 14, 2011 #9


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    Perhaps, but remember that people have to work with the mass of these particles on a daily basis. What difference does it make to them? The final number they must use is still the same. Besides, in areas which actually deal with quarks and bosons I'm guessing that those people actually do understand why the rest mass of 3 quarks is far less than that of a nucleon as a whole.

    Also, consider any system composed of more than one particle. The mass of the system must also include the different types of energy as far as I know.
  11. Dec 14, 2011 #10
    So is my mass made up of "higgs mass" and "kinetic mass"?
  12. Dec 14, 2011 #11


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    In part yes. I don't know if there are other things that contribute to the mass of a nucleon.
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