Massless Charged Particle

GeometricProblems.MasslessChargedParticleModule

Massless charged particle in 2D

The Lagrangian is given by

\[L(x, \dot{x}) = A(x) \cdot \dot{x} - \phi (x) ,\]

with magnetic vector potential

\[A(x) = \frac{A_0}{2} \big( 1 + x_1^2 + x_2^2 \big) \begin{pmatrix} - x_2 \\ + x_1 \\ \end{pmatrix} ,\]

electrostatic potential

\[\phi(x) = E_0 \, \big( \cos (x_1) + \sin(x_2) \big) ,\]

and magnetic and electric fields

\[\begin{aligned} B(x) &= \nabla \times A(x) = A_0 \, (1 + 2 x_1^2 + 2 x_2^2) , \\ E(x) &= - \nabla \phi(x) = E_0 \, \big( \sin x_1, \, - \cos x_2 \big)^T . \end{aligned}\]

The Hamiltonian form of the equations of motion reads

\[\dot{x} = \frac{1}{B(x)} \begin{pmatrix} \hphantom{-} 0 & + 1 \\ - 1 & \hphantom{+} 0 \\ \end{pmatrix} \nabla \phi (x) .\]

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