Higher Fock sectors in Wick-Cutkosky model

TL;DR

This paper nonperturbatively analyzes the contributions of various Fock sectors to the norm and form factor in the Wick-Cutkosky model, revealing dominance of two- and three-body sectors and their behavior with coupling strength.

Contribution

It provides a detailed nonperturbative analysis of Fock sector contributions in the Wick-Cutkosky model using light-front dynamics, highlighting sector dominance and asymptotic behavior.

Findings

Two- and three-body sectors dominate the norm.

At maximal coupling, these sectors contribute 90%.

Two-body sector determines the form factor asymptotics.

Abstract

In the Wick-Cutkosky model we analyze nonperturbatively, in light-front dynamics, the contributions of two-body and higher Fock sectors to the total norm and electromagnetic form factor. It turns out that two- and three-body sectors always dominate. For maximal value of coupling constant $\alpha=2\pi$, corresponding to zero bound state mass M=0, they contribute 90% to the norm. With decrease of $\alpha$ the two-body contribution increases up to 100%. The form factor asymptotic is always determined by two-body sector.