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8 votes

From what equations is magnetic field uniquely determined for a given current distribution?

The domain is important. The solution is given by Biot-Savart if it is the entire $\mathbb R^3$ space, with some assumptions on the regularity and decay of $B$ (e.g. $L^2$). In this case, you can ...
LPZ's user avatar
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1 vote
Accepted

Flux change through a loop

This comes from Faraday's law. I believe it is only valid in quasistatic (no radiation generated) situations. Faraday's law in differential form is $$-\frac{d\Phi_B}{dt} = \varepsilon.$$ If you have a ...
mike1994's user avatar
  • 978
0 votes
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Maxwell stress tensor on a capacitor late given a dielectric

I figured out the answer to my question! Although I couldn't find any reference to the Maxwell stress tensor in a dielectric in my normal Griffiths textbook, I found that "Electrodynamics of ...
asyndeton256's user avatar
-2 votes

Derivation of Lorentz transformation from Maxwell's equations

The Lorentz transformations are defined by the condition that they leave c$^2$dt$^2$-dr$^2$=0. This condition comes from the Maxwell equations combined with the Michelson-Morley result. In this sense ...
my2cts's user avatar
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0 votes

Maxwell stress tensor on a capacitor late given a dielectric

$E_{zz}= \varepsilon_r$V/d so that's where the relative permittivity is hiding. The Feynman lectures may be helpful.
Spehro Pefhany's user avatar
2 votes

The puzzling interaction between an anapole moment and external fields

A pure anapole produces no radiation, no matter how it is varied or rotated, and has no interaction with free external fields. Sources online seem to disagree on this point, but it might be because of ...
knzhou's user avatar
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4 votes

The puzzling interaction between an anapole moment and external fields

Mathematically, a dipole can be seen as a small current loop. Given the dipole moment $m$ this gives the magnetisation and current density: $$ M = m\delta \quad j = \nabla\times M = \nabla\times (m\...
LPZ's user avatar
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