Given the task definition and input, reply with output. In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Schrodinger-Pauli equation sees this quantity multiplied by charge and subtracted from the momentum three vector. An electron's interference pattern changes when a solenoid turns on despite the fact that the magnetic field outside of the solenoid is zero because of this quantity. For a non-conservative electric field, the electric field is equal to the negative gradient of the electric potential minus the time derivative of this quantity. In addition to causing the Aharonov-Bohm effect, this quantity is combined with the electric potential to form the 4-potential. This quantity's divergence is set to zero in the Coulomb gauge. For 10 points, magnetic field is defined as the curl of this quantity that is symbolized A.

Science