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0 votes
1 answer
66 views

How to describe the dynamics of a magnetic monopole charge in the external EM field using a Lagrangian in terms of the EM potentials?

The equation of motion of a magnetic charge in the fixed external electromagnetic field $\mathbf{E},\mathbf{B}$ is $$ \frac{d}{dt}(\gamma m \mathbf{v})=q_m(\mathbf{B}-\mathbf{v}\times\mathbf{E}), $$ ...
hao123's user avatar
  • 21
0 votes
0 answers
58 views

Least action principle for Dirac monopole

I want to find the Lorentz force formula for the magnetic charge through the principle of least action. The magnetic charge is introduced by Dirac adding inside the electromagnetic tensor a tensor $G^{...
Pietro Scapolo's user avatar
1 vote
0 answers
122 views

Lagrangian formulation of Maxwell's equations with magnetic monopole

If we set $\nabla \cdot {\bf B}=\rho_m$ where pm is the density of magnetic charges we lose the ability to write ${\bf B}=\nabla \times{\bf A}$ . Can we get a new Lagrangian that leads to the new ...
CoolerThanACooler's user avatar
1 vote
0 answers
129 views

Force law from Lagrangian for magnetic monopole

How to construct a Lagrangian that gives the Lorentz force law with both magnetic and electric monopole? I got that the force will be of the form \begin{equation} m \frac{\mathrm{d}x^\nu}{\mathrm{d}\...
user824530's user avatar
0 votes
0 answers
243 views

Magnetic monopole Lagrangian and Hamiltonian

How do I find an equation analogous to \begin{equation} \mathcal{L}(q,\dot q)=\frac12 m \dot q ^2-q\phi+q\vec{\dot q}\cdot \vec A\quad\quad \text{where}\quad \vec B =\vec\nabla\times\vec A, \quad \vec ...
user824530's user avatar
4 votes
1 answer
666 views

Is there either a Lagrangian or a Hamiltonian formulation of electromagnetism with continuous distributions of magnetic monopoles?

Maxwell's equations generalize very nicely if we add in magnetic monopoles: we get $$\begin{align*} \partial_\mu F^{\mu \nu} &= J^\nu \\ \partial_\mu \tilde{F}^{\mu \nu} &= \tilde{J}^\nu, \end{...
tparker's user avatar
  • 48.4k
10 votes
1 answer
2k views

Magnetic monopoles in field theory

In standard QED, we couple the electron to electromagnetism by replacing $$\partial_\mu \to \partial_\mu + i e A_\mu.$$ Upon taking the classical limit, we find that this gives electrons an electric ...
knzhou's user avatar
  • 103k
10 votes
1 answer
1k views

How will SR EM Lagrangian change if we find a magnetic charge?

When we introduce electromagnetic field in Special Relativity, we add a term of $$-\frac e c A_idx^i$$ into Lagrangian. When we then derive equations of motion, we get the magnetic field that is ...
Ruslan's user avatar
  • 29.1k