= Larmor theorem
{c}
{title2=$\boldsymbol\omega=-e\mathbf B/(2m)$}
For particles with the same charge-to-mass ratio, rotationally invariant mutual <central forces>, and a weak uniform <magnetic field>, a frame with the displayed <angular velocity> cancels the velocity-dependent magnetic <Lorentz force> against the <Coriolis force>. The remaining rotational and magnetic terms are quadratic in $\mathbf B$. Thus, to first order in the field, the rotating-frame equations coincide with the zero-field equations. This is the classical dynamical basis of <Larmor precession>; equality is an approximation rather than an exact removal of the magnetic field.
Back to article page
