For 10 points, name this operation that relates the magnetic vector potential to the B-炬eld and is denoted "del cross."
This operation takes place at each "leapfrog" time step of the Yee algorithm. In computational MHD, a fourth-order instance of this operation is o畔ten replaced by a di猼ferent operation that is second-order but has 220 degrees of freedom per conforming 炬nite element. The magnitude squared of this operation appears in the expression for the rate of change of magnetic energy due to Joule heating. Along with the time derivative, this operation modi炬es the superconducting current density in the London equations. The free-space electromagnetic wave equation may be derived by performing this operation on both sides of the di猼ferential formulation of Faraday's law or Ampère's law, then using the identity that applying this operation twice is equivalent to subtracting the Laplacian from the gradient of the divergence. For 10 points, name this operation that relates the magnetic vector potential to the B-炬eld and is denoted "del cross."
This operation takes place at each "leapfrog" time step of the Yee algorithm.
curl [accept del cross until mentioned; anti-prompt on spatial derivative]