The light-front coupled-cluster method applied to $\phi_{1+1}^4$ theory

TL;DR

This paper applies the light-front coupled-cluster method to compute eigenstates in 1+1 dimensional $\

Contribution

It introduces the LFCC method as an alternative to Fock-space truncation for solving quantum field theories, avoiding Fock space restrictions.

Findings

LFCC yields finite nonlinear equations for eigenstates.

Results compare favorably with Fock-space truncation methods.

Demonstrates effectiveness in $\

Abstract

We use the light-front coupled-cluster (LFCC) method to compute the odd-parity massive eigenstate of $\phi_{1+1}^4$ theory. A standard Fock-space truncation of the eigenstate yields a finite set of linear equations for a finite number of wave functions. The LFCC method replaces Fock-space truncation with a more sophisticated truncation; the eigenvalue problem is reduced to a finite set of nonlinear equations without any restriction on Fock space, but with restrictions on the Fock wave functions. We compare our results with those obtained with a Fock-space truncation.