# A Worm Algorithm for the Lattice CP(N-1) Model

## TL;DR

This paper introduces a new worm algorithm for efficiently simulating the 2D lattice CP(N-1) model, a simplified analog of QCD, especially effective at finite density and in a dual flux-variables representation.

## Contribution

The paper presents a novel worm algorithm tailored for the lattice CP(N-1) model that operates efficiently at finite density in a dual flux-variables framework.

## Key findings

- Algorithm successfully simulates the model at finite density.
- Efficient handling of chemical potential without complications.
- Potential for application to related lattice gauge theories.

## Abstract

The CP(N-1) model in 2D is an interesting toy model for 4D QCD as it possesses confinement, asymptotic freedom and a non-trivial vacuum structure. Due to the lower dimensionality and the absence of fermions, the computational cost for simulating 2D CP(N-1) on the lattice is much lower than the one for simulating 4D QCD. However to our knowledge, no efficient algorithm for simulating the lattice CP(N-1) model has been tested so far, which also works at finite density. To this end we propose and test a new type of worm algorithm which is appropriate to simulate the lattice CP(N-1) model in a dual, flux-variables based representation, in which the introduction of a chemical potential does not give rise to any complications.