 
Summary: Nuclear Physics B139 (1978) 159169
0 NorthHolland Publishing Company
CALCULATING QUANTUM CORRECTIONS TO THE MASS OF A
SOLITON WITHOUT COLLECTIVE COORDINATES *
L.F. ABBOTT l *
Department of Physics, Brandeis Univertity, Waltham, Massachusetts 02154, USA
Received 14 November 1977
(Revised 13 March 1978)
Feynman rules are derived for computing quantum corrections to the mass of a
soliton in quantum field theory. These rules exhibit a finite propagator, but in contrast
to previous methods, no additional effective vertices are introduced beyond those pre
sent in the original shifted Lagrangian. The derivation is based on imposing endpoint
boundary conditions appropriate to a soliton state on the functional integral represent
ing the solitontosoliton transition amplitude.
1. Introduction
During the past few years, a great deal of attention has been given to the problem
of constructing a perturbation expansion around a nondissipative, finiteenergy solu
tion to the classical field equations of a quantum field theory [l9] l**. Classical
"lumplike" solutions are interpreted as representing particles called solitons. To
investigate the quantum corrections to various physical processes one must derive
