The first order expansion of a ground state energy of the model with cutoffs
arXiv:2012.04907 · doi:10.1063/5.0040022
Abstract
In this paper, we investigate the model with cutoffs. By introducing a spatial cutoff and a momentum cutoff, the total Hamiltonian is a self-adjoint operator on a boson Fock space. Under regularity conditions of the momentum cutoff, we obtain the first order expansion of a non-degenerate ground state energy of the total Hamiltonian.