On simultaneous approximation of several eigenvalues of a semi-definite self-adjoint linear operator in a Hilbert space
arXiv:1902.06722
Abstract
A lower semi-definite self-adjoint linear operator in a Hilbert space is taken whose discrete spectrum is not empty and comprises at least several eigenvalues . The problem of approximation of these eigenvalues by eigenvalues of some linear operator in a finite-dimensional space of the dimension is considered and solved. The accuracy of the approximation obtained becomes unlimitedly high as .
AmSTeX, 10 pages, amsppt style