An Etymological Dictionary of Astronomy and Astrophysics

In quantum mechanics, the condition of parity in strong and electrodynamic interactions, where it remains constant and does not change with time. In other words, parity conservation implies that Nature is symmetrical and makes no distinction between right- and left-handed rotations or between opposite sides of a subatomic particle. Thus, for example, two similar radioactive particles spinning in opposite directions about a vertical axis should emit their decay products with the same intensity upward and downward. Same as → parity symmetry.

See also: → parity; → conservation.