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I was just wondering about the nature of fields. What

*are*they? Since fields carry energy, and energy is mass, does that mean that fields are equivalent to mass?? I think this is probably incorrect, but I just have no clue why.

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I was just wondering about the nature of fields. What

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Very interesting question, I'm not sure that fields carry energy though, it's more about the interactions with the field, the field itself isnt energy (at least I think so). And from the interactions, energy can convert into mass, thanks to the field but I don't think there is a field energy that would need to be "consumed" by the creation of mass.

But I think I know nothing more than you on this subject, it's just what I think without proofs.

I would take the example of an electron and a proton, they each have an electromagnetic field, and when they are separated their fields interact to get them closer, the energy being used is the electromagnetical potential energy, which is transfered to the kinetic energy of these particles to give them speed, thanks to the work of the electromagnetical force. So energy has been used, but when you look the state of the system afterwards (let's say after the creation of a hydrogen atom), each particle still has the same field than before, so I don't think field is energy, it would just be some kind of way of interaction I think.

But I think I know nothing more than you on this subject, it's just what I think without proofs.

I would take the example of an electron and a proton, they each have an electromagnetic field, and when they are separated their fields interact to get them closer, the energy being used is the electromagnetical potential energy, which is transfered to the kinetic energy of these particles to give them speed, thanks to the work of the electromagnetical force. So energy has been used, but when you look the state of the system afterwards (let's say after the creation of a hydrogen atom), each particle still has the same field than before, so I don't think field is energy, it would just be some kind of way of interaction I think.

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CompuChip

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Actually, photons are the particles that mediate the EM interactions. In field theory, one would say that the field itself just exists everywhere in space. Photons are then excitations of the EM field, and as such, have a certain energy (above the ground state of the field) which one could indeed view as relativistic mass. This is a general principle in modern physics (field theory, Standard Model, string theory), where particles are seen as excitations of some field, and the energy of the excitation is related to the mass of the particle; for example, the relationBasically, light is an EM field

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Thanks.

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think of an electron and positron that come together. in the end their fields cancel out completely and all potential field energy in converted to light.

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In some situations there is a direct equivalence between mass and energy given by E = mc

I was just wondering about the nature of fields. Whatarethey? Since fields carry energy, and energy is mass, does that mean that fields are equivalent to mass?? I think this is probably incorrect, but I just have no clue why.

Pete

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integrated over infinite space the total energy is finite and well below rest mass for electrons and protons.

meaning, the energy stored in the field of an electron or proton integrated over infinite space is finite and well below the rest mass of the electron or proton.

meaning, the energy stored in the field of an electron or proton integrated over infinite space is finite and well below the rest mass of the electron or proton.

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What is it that your speaking of when you are integrating over infinite space? The total energy of what? And why do you think this is below the rest mass of both the proton and the electron? When I was speaking about integrating over all space I was refering to integrating the energy of the field over space.integrated over infinite space the total energy is finite and well below rest mass for electrons and protons.

You seem to be speaking about electromagnetic mass. The eletromagnetic mass of a classical particle only makes sense of the "particle" has a finite size. If the particle is a true mathematcal point then the self-energy would be infinite.meaning, the energy stored in the field of an electron or proton integrated over infinite space is finite and well below the rest mass of the electron or proton.

If the particle has a finite size and one assumes that it is a sphere (either uniformly charged or has a uniform surface charge distribution where the charge is spread out over the surface of the sphere) then the total inertial mass of the proton, i.e. its rest mass, is given by

m

[when (v -> 0)] where the m

(The term "particle," as used here, refers to the idea that the size of the body can be neglected in the problem one is considering. As such there is no objective way to determine whether something is a point particle or not.)

Pete

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