We see leptons and quarks possessing charges. Can there be charge in free space devoid of matter(neither leptons nor quarks or anything else)?
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This is quite hypothetical; in what model of particle physics? in what model of cosmology? – innisfree Jan 31 '19 at 07:43
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Is there something that has nothing other than charge? No mass and no other property. – Sai Baikampadi Jan 31 '19 at 07:59
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A better way to ask this is :- Gravity is a bend or distortion in space time fabric due to mass. A specific bend in STF would be as good as gravitational field there. In that sense, what is charge and its field? Could we have charges in free space – Sai Baikampadi Jan 31 '19 at 08:10
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Even holes in semi-conductors have an effective mass! They can be a few percent of the mass of the electron though. So no, not in any model that I know of… – Feb 01 '19 at 07:56
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Duplicate I think. – Feb 01 '19 at 08:00
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No, charge is a property of a particle not a thing in its own right, so it is always associated with a particle.
In principle a charge could be associated with a massless particle, and perhaps you would not count that as matter. In practice no such particles can exist or we would have seen them in collider experiments.
John Rennie
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1@innisfree The only theories we have that describe black holes are classical and have nothing to say about the properties of fundamental particles. As far as we know any black hole acquired its charge by absorbing charged particles. Whether the particles still exist in the usual sense after they've crossed the event horizon is an intriguing one, but this is unanswerable without some theory of quantum gravity. – John Rennie Jan 31 '19 at 08:39
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In the standard model, before symmetry breaking all particles are massless but retain their quantum numbers, including charge, otherwise the symmetries would be destroyed – anna v Jan 31 '19 at 08:40
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Yes, and even in the context of GR, are charged black hole solutions vacuum solutions? If not, maybe we cannot say they are devoid of matter? – innisfree Jan 31 '19 at 08:42
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1As the question I have linked explains there is nothing in quantum field theory that prevents a massless particle having a charge. The observation that no massless charged particles exist is purely empirical. – John Rennie Jan 31 '19 at 08:43
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1@innisfree A vacuum solution is one in which the stress-energy tensor is zero. For a charged black hole the stress-energy tensor is not zero because the electromagnetic field contributes to the stress-energy tensor. General relativity does not distinguish between mass and energy in the stress-energy tensor. – John Rennie Jan 31 '19 at 08:47
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While gravity is a curvature of spacetime, electromagnetism can be viewed as a curvature of the $U(1)$ principal bundle:
Classical electrodynamics as the curvature of a line bundle
This however doesn't mean that empty space has charge. Instead, charge is the cause of the line bundle curvature. Similarly, in general relativity, mass (or, more precisely, stress-energy tensor) is the cause of gravity described as a spacetime curvature.
safesphere
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I have to repeat my comment. In the Big Bang cosmological model before the symmetry breaking of the electroweak force, the zero mass particles, electrons , quarks, have their charges,otherwise the symmetry groups would be destroyed. – anna v Feb 01 '19 at 16:55
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+1 for the curvature, but actually, I don't think charge is the cause of the line-bundle curvature. We can make charged particles out of gamma photons in gamma-gamma pair production. So we start with electromagnetism of sorts, but those gamma photons have no charge. – John Duffield Aug 26 '20 at 18:47
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In the Standard Model, the only way to have charge is to have a charged particle: a quark, an electron/muon/tau, or a W boson. All of these charged particles also have mass.
G. Smith
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Before symmetry breaking all particles are massless but have charge and the other quantum numbers – anna v Jan 31 '19 at 08:39