Kramer's theorem

Kramer's theorem

[′krā·mərz ‚thir·əm]
(solid-state physics)
The theorem that the states of a system consisting of an odd number of electrons in an external electrostatic field are at least twofold degenerate.
References in periodicals archive ?
In [1969c], for example, Abdul calculated certain sampling functions by specializing Kramer's theorem. Some cases he considers are the special functions of Laguerre, Gegenbauer, and Chebyshev, the spheroidal wave functions, and certain special functions associated with fourth order boundary value problems.
The main drawbacks in Kramer's theorem is the fact that eigenvalues are dictated by the given boundary value problem, and thus are fixed and obviously cannot be changed as one wishes.
Kramer's theorem then yields a sampling formula for the given sampling points.