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Totally sensible, and it's actually probably the easiest way for me to think about it as well :) A proton or neutron has a mass of approximately 1 GeV/c^2. Th

Totally sensible, and it's actually probably the easiest way for me to think about it as well :) A proton or neutron has a mass of approximately 1 GeV/c^2. The Higgs boson has a mass of about 125 GeV/c^2 -- so it's totally appropriate to think about it as being 125x heavier than a proton, or about as heavy as an Iodine nucleus. The top quark has a mass of 170 GeV/c^2 -- it's the most massive fundamental particle we've discovered so far!

jcims 8y ago
Wow! I'm glad I asked because this just flipped my mental model completely. Now I have to do some investigating, thank you!!!
ff317 8y ago
So I have another silly non-physicist question at this point: if Higgs is what gives particles mass, and it has a mass of 125 GeV/c^2, why doesn't this imply mass can only be conferred in units of this amount? We obviously have smaller particles with "real" masses (e.g. nuclei lighter than iodine). Is it that the Higgs is coupled by a varying degree which confers only part of its mass to the coupled particle? In that case, can a single Higgs be lightly-coupled to several distinct particles? Does this imply some other spooky connections/behaviors between multiple particles sharing partial couplings to a single Higgs?
- Koshkin 8y ago
  > Higgs is what gives particles mass Depending on the particle: https://www.youtube.com/watch?v=Ztc6QPNUqls https://www.youtube.com/watch?v=Ztc6QPNUqls
- cshimmin 8y ago
  Roughly, you can actually think of the mass of these fundamental particles being _defined_ by how much they interact with the Higgs field. Higgs bosons themselves interact with the Higgs field, to an extent that their mass comes out to be ~125 GeV/c^2. Tau leptons interact with it less, so their mass is 1.7 GeV/c^2. The key point is that the strength of the interaction of any given particle type with the Higgs field is a totally arbitrary, free parameter of the theory that we only know by measuring those particles (with the exception of electroweak bosons, which have a constrained relationship with the Higgs due to electroweak symmetry). A very deep open question in physics is whether there is some more structured theory that explains exactly why these parameters have their values, or at least, how the parameters for different particles are related. As a side node, the proton actually gets almost none of its mass from the Higgs field! That's because the Higgs mechanism only gives mass to fundamental particles in the theory, and protons are made up of quarks and gluons bound together in a potential of the strong nuclear force. The quarks within a proton are very light, and the gluons are completely massless, so it is actually the binding energy of these particles that yields the effective mass of the proton (this is E=mc^2 at work).
  - jcims 8y ago
    This is super cool info, thank you for sharing!

jcims 8y ago

Wow! I'm glad I asked because this just flipped my mental model completely. Now I have to do some investigating, thank you!!!

ff317 8y ago

So I have another silly non-physicist question at this point: if Higgs is what gives particles mass, and it has a mass of 125 GeV/c^2, why doesn't this imply mass can only be conferred in units of this amount? We obviously have smaller particles with "real" masses (e.g. nuclei lighter than iodine). Is it that the Higgs is coupled by a varying degree which confers only part of its mass to the coupled particle? In that case, can a single Higgs be lightly-coupled to several distinct particles? Does this imply some other spooky connections/behaviors between multiple particles sharing partial couplings to a single Higgs?

Koshkin 8y ago
> Higgs is what gives particles mass Depending on the particle: https://www.youtube.com/watch?v=Ztc6QPNUqls https://www.youtube.com/watch?v=Ztc6QPNUqls
cshimmin 8y ago
Roughly, you can actually think of the mass of these fundamental particles being _defined_ by how much they interact with the Higgs field. Higgs bosons themselves interact with the Higgs field, to an extent that their mass comes out to be ~125 GeV/c^2. Tau leptons interact with it less, so their mass is 1.7 GeV/c^2. The key point is that the strength of the interaction of any given particle type with the Higgs field is a totally arbitrary, free parameter of the theory that we only know by measuring those particles (with the exception of electroweak bosons, which have a constrained relationship with the Higgs due to electroweak symmetry). A very deep open question in physics is whether there is some more structured theory that explains exactly why these parameters have their values, or at least, how the parameters for different particles are related. As a side node, the proton actually gets almost none of its mass from the Higgs field! That's because the Higgs mechanism only gives mass to fundamental particles in the theory, and protons are made up of quarks and gluons bound together in a potential of the strong nuclear force. The quarks within a proton are very light, and the gluons are completely massless, so it is actually the binding energy of these particles that yields the effective mass of the proton (this is E=mc^2 at work).
- jcims 8y ago
  This is super cool info, thank you for sharing!