Modified similarity renormalization of Hamiltonians. QED on the light front

TL;DR

This paper introduces a modified similarity renormalization method for Hamiltonians using flow equations, enabling effective renormalization in energy space and working within truncated Fock spaces for quantum field theories.

Contribution

It presents a novel approach to Hamiltonian renormalization that facilitates calculations in truncated Fock spaces using flow equations.

Findings

Enables renormalization in energy space

Allows working with truncated Fock spaces

Improves computational feasibility for quantum field theories

Abstract

Modified similarity renormalization of Hamiltonians is proposed, that performes by means of flow equations the similarity transformation of Hamiltonian in the particle number space. This enables to renormalize in the energy space the field theoretical Hamiltonian and makes possible to work in a severe trancated Fock space for the renormalized Hamiltonian.