The Hoffman-Wielandt inequality, which gives a bound for the distance between the spectra of two normal matrices, is generalized to normal operators A, B on a separable Hilbert space, such that A - B is Hilbert-Schmidt.
The Hoffman-Wielandt inequality, which gives a bound for the distance between the spectra of two normal matrices, is generalized to normal operators A, B on a separable Hilbert space, such that A - B is Hilbert-Schmidt.