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1 vote
1 answer
67 views

Potential and integral (electrodynamics)

I'm supposed to find the vector potential $A(x)$ the field generated by an infinite conducting wire of section $\pi a^2$, in which flows a constant current density $j=j \cdot \theta(a-r)\hat{z}$ ...
Tomy's user avatar
  • 429
1 vote
0 answers
41 views

Electrostatic potential of a charge in a 3-torus

Consider the 3-torus which arises from taking $R^3$ and identifying two points $x\equiv x+nL$ whenever $n$ is a vector with integer components. I'm curious about finding the electrostatic potential ...
Matt Dickau's user avatar
  • 2,289
1 vote
1 answer
244 views

Differential equation for a vector potential

From Helmholtz’s theorem, any smooth vector field $\mathbf{F}$ that goes to zero at infinite distance can be uniquely decomposed everywhere in the sum of a divergence free component and an ...
Simo's user avatar
  • 41
1 vote
0 answers
59 views

References for magnetic Sobolev spaces

I am working on PDE. Recently I have been studying magnetic Sobolev spaces. While the theory is clear to me, having very little knowledge about physics, I have almost no idea how these spaces help ...
kaushik's user avatar
  • 31
3 votes
0 answers
104 views

Why is electric potential function in free space infinitely differentiable?

Electric potential function in free space of a continuous charge distribution $\rho'$ distributed over volume $V' \subset \mathbb{R}^3$ is denoted by: $\psi (x,y,z): \mathbb{R}^3 \setminus{V'} \to \...
Joe's user avatar
  • 1,141
2 votes
1 answer
126 views

Dirichlet problem on a wire: a co-dimension 2 boundary condition

A wire may be thought of as a smooth compact curve $C \subset \mathbb{R}^3$ with boundary two endpoints. Suppose we are given a smooth $\phi: C \to \mathbb{R}$ (a potential on the wire), then can $\...
Mathemagician's user avatar
0 votes
2 answers
239 views

Evaluate $\int_0^{2\pi}\ln(1+a^2-2a\cos(x))dx\text{ ,with }a>0$ [duplicate]

$$\int_0^{2\pi}\ln(1+a^2-2a\cos(x))dx,\;\;\;\;\text{with }a>0$$ How to evaluate Integral of $\ln(1+a^2-2a\cos x) dx$? where $x$ from $0$ to $2\pi$ and $a>0$, $\ln$ is the natural logarithm.
Aria's user avatar
  • 422
3 votes
0 answers
82 views

Charge density of charged conductor with flat side

Given a charged conducting body with a flat side, can the charge density (and hence the normal electric field) be constant on the flat part? According to physics lore, the charge density is greater ...
Keith McClary's user avatar