Effects of Electromagnetic mass indistinguishable from regular mass?

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An electrically charged particle generates an electric field that extends into space, with an energy density proportional to the electric field squared, which can be equated to mass density via Einstein's E=mc^2. As the particle moves, it carries a "cloud" of mass associated with its electric field, leading to the question of whether this electromagnetic mass influences the particle's dynamics like its regular mass. It is suggested that the total mass of a charged particle can be viewed as the sum of its localized regular mass and its electromagnetic mass, which is spread throughout space. General relativity indicates that electromagnetic fields do curve spacetime and participate in gravitational interactions, although the effects are minimal and likely unobservable. Ultimately, the electromagnetic self-energy contributes a finite amount to the particle's mass, reinforcing the connection between energy density and mass density.
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An electrically charged particle has an electric field centred around itself that extends far into space.

That field has an energy density proportional to the electric field squared.

By Einstein's E=mc^2 that energy density is equivalent to a mass density.

Thus, as a charged particle moves, it carries around with itself a "cloud" of mass in its electric field.

If we assume the particle has a finite radius then the total mass in its electric field is finite.

The centre of mass of this field mass/energy is located at the particle's postion and so moves with it.

My question is this:

Does this electromagnetic mass affect the particle's dynamics in exactly the same way as its "regular" mass even though it is spread diffusely throughout space?

Thus is it true to say that:

mass of charged particle = regular mass (localized at the particle position) + electromagnetic mass (extended throughout space)?
 
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johne1618 said:
An electrically charged particle has an electric field centred around itself that extends far into space.

That field has an energy density proportional to the electric field squared.

By Einstein's E=mc^2 that energy density is equivalent to a mass density.

Thus, as a charged particle moves, it carries around with itself a "cloud" of mass in its electric field.

If we assume the particle has a finite radius then the total mass in its electric field is finite.

The centre of mass of this field mass/energy is located at the particle's postion and so moves with it.

My question is this:

Does this electromagnetic mass affect the particle's dynamics in exactly the same way as its "regular" mass even though it is spread diffusely throughout space?

Thus is it true to say that:

mass of charged particle = regular mass (localized at the particle position) + electromagnetic mass (extended throughout space)?

I don't know how correct it is to say that any energy density is really a mass density, it's really more of a one way street (mass density is an energy density). However, ultimately your question comes down to the following: Does the electromagnetic FIELD (which carries energy) also participate in gravitational interactions. According to general relativity the answer is yes, EM fields DO curve spacetime just as any energy does... However, the effect is also predicted to be so slight that I highly doubt it's ever been observed (and it is hardly a dominant effect).
 
http://arxiv.org/abs/0905.2391
A Rigorous Derivation of Electromagnetic Self-force
Samuel E. Gralla, Abraham I. Harte, Robert M. Wald
"Interestingly, we will also see that the electromagnetic self-energy of the body makes a non-zero, finite contribution to the particle’s mass."
 
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