Quasisecular Renormalization of theφ4Model of Quantum Field Theory

Abstract
The Heisenberg equations of the φ4 model of quantum field theory in one space dimension are analyzed by a modified perturbation method. The modification focuses on terms with vanishing and small energy denominators. These terms give rise to operator-valued frequency (mass) renormalization and amplitude (wave-function) renormalization. These renormalization effects remain present in the limit of an infinite system because the number of terms with small energy denominators becomes infinite.