Quantum numbers a way of representing a state by several numbers, which corresponds to a complete set of commuting observables. A common example of quantum numbers is the possible state of an electron in a central potential: ( n , l , m , s ) {\displaystyle (n,l,m,s)} , which corresponds to the eigenstate of observables H {\displaystyle H} (in terms of r {\displaystyle r} ), L {\displaystyle L} (magnitude of angular momentum), L z {\displaystyle L_{z}} (angular momentum in z {\displaystyle z} -direction), and S z {\displaystyle S_{z}} .