B Relativistic Mass-Energy: Charge & Particles

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The presence of charge contributes to relativistic mass-energy due to the associated electromagnetic field, which has stress-energy. It is not necessary for two particles to attract or repel each other to generate charge-related mass-energy. The Reissner–Nordström metric illustrates how charged black holes exhibit different gravitational properties compared to uncharged ones, with a significant portion of their 'mass' attributed to charge. When charge is removed, the black hole's mass reduces to its irreducible mass, resulting in a distinct change in the gravitational field. Overall, charge plays a crucial role in the mass-energy dynamics of charged particles and black holes.
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Does The Presence of Charge Add To Relativistic Mass-Energy, or does it take two particles attracting or repelling one another to generate charge-related mass-energy?
 
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1977ub said:
Does The Presence of Charge Add To Relativistic Mass-Energy,

Yes. The presence of charge means there is an electromagnetic field, and the electromagnetic field has stress-energy.

1977ub said:
does it take two particles attracting or repelling one another to generate charge-related mass-energy?

No.
 
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1977ub said:
Does The Presence of Charge Add To Relativistic Mass-Energy, or does it take two particles attracting or repelling one another to generate charge-related mass-energy?

While PeterDonis has answered the question, you can see this at work in the Reissner–Nordström metric which is the vacuum solution for a charged black hole. Gravity for a charged black hole is-

a_g=\frac{M}{r^2\sqrt{1-\frac{2M}{r}-\frac{Q^2}{r^2}}}

where M=Gm/c^2 (mass in geometric units) and Q=C\sqrt(Gk_e)/c^2 (charge in geometric units) where G is the gravitational constant, c is the speed of light, C is the charge in Coulombs and k_e is Coulomb's constant (as a rule, M\geq Q). Multiply the answer by c^2 for S.I. units of gravity (m/s2).

If charge is removed and the black hole is reduced to it's irreducible mass (the same black hole becoming a Schwarzschild black hole) where-

M_{\text{ir}}=\frac{r_+}{2}\ \ \rightarrow\ \ M=\frac{Q^2}{4M_{\text{ir}}}+M_{\text{ir}}

where M_{\text{ir}} is the irreducible mass and r_+=M+\sqrt{M^2-Q^2} is the outer event horizon, the equation for gravity becomes-

a_g=\frac{M{\text{ir}}}{r^2\sqrt{1-\frac{2M{\text{ir}}}{r}}}

you'll notice a distinct drop in the gravity field at a specific r some distance from the black hole. It might also be worth looking at Kerr-Newman metric which also includes for spin. Up to 50% of RN black hole's 'mass' can be attributed to charge though charged black holes are not considered realistic.

More info-
https://www.physicsforums.com/threads/what-is-irreducible-mass.762993/
 
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Moderator's note: Spin-off from another thread due to topic change. In the second link referenced, there is a claim about a physical interpretation of frame field. Consider a family of observers whose worldlines fill a region of spacetime. Each of them carries a clock and a set of mutually orthogonal rulers. Each observer points in the (timelike) direction defined by its worldline's tangent at any given event along it. What about the rulers each of them carries ? My interpretation: each...

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