1995/04/06 by L. Feld, R. Rosenfelder, Andreas Schreiber +1 · 1 citation
Mathematics · Physics and Astronomy · #Ansatz #Black Holes and Theoretical Physics #Coupling constant #Feynman diagram #Geometry #Mathematical physics #Mathematics #Particle physics theoretical and experimental studies #Physics #Polaron #Propagator #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Scalar (mathematics) #Variational method #nucl-th
paper · pdf · doi:10.1103/physrevd.53.3354
published as Phys.Rev. D53 (1996) 3354-3365 · 25 pages standard LaTeX, 9 uuencoded postscript figures embedded with psfig.sty
arxiv created 1995/04/06 · openalex publication_date 1996/03/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
For the scalar Wick-Cutkosky model in the particle representation we perform a similar variational calculation for the two-point function as was done by Feynman for the polaron problem. We employ a quadratic nonlocal trial action with a retardation function for which several Ans"atze are used. The variational parameters are determined by minimizing the variational function and in the most general case the nonlinear variational equations are solved numerically. We obtain the residue at the pole, study analytically and numerically the instability of the model at larger coupling constants, and calculate the width of the dressed particle. \textcopyright 1996 The American Physical Society.