Abstract:
We consider a model describing a "truncated" operator (truncated with
respect to the number of particles) acting in the direct sum of zero-,
one-, and two-particle subspaces of a Fock space. Under some natural
conditions on the parameters specifying the model, we prove that the discrete
spectrum is finite.
Keywords:discrete spectrum, Fock space, compact operator, continuity in the uniform operator topology, Hilbert–Schmidt operator, Weinberg equation.