In physics a conserved current is a current, that satisfies the continuity equation . The continuity equation represents a conservation law, hence the name.
Indeed, integrating the continuity equation over a volume, large enough to have no net currents through its surface, leads to the conservation law
where is the conserved quantity.
In gauge theories the gauge fields couple to conserved currents. For example, the electromagnetic field couples to the conserved electric current.
Read more about Conserved Current: Conserved Quantities and Symmetries, Conserved Currents in Electromagnetism
Famous quotes containing the word current:
“Absolutely speaking, Do unto others as you would that they should do unto you is by no means a golden rule, but the best of current silver. An honest man would have but little occasion for it. It is golden not to have any rule at all in such a case.”
—Henry David Thoreau (1817–1862)