New techniques and results for worldline simulations of lattice field theories

TL;DR

This paper advances worldline simulation techniques for lattice field theories, focusing on complex $^4$ models at finite density, introducing new algorithms, canonical methods, and exploring physical phenomena like 2-particle condensation.

Contribution

It presents novel variants of the worm algorithm, explores canonical simulation approaches, and connects low-temperature condensation to scattering parameters in worldline formulations.

Findings

Developed new worm algorithm variants for site-weighted systems

Demonstrated feasibility of canonical worldline simulations

Linked 2-particle condensation to scattering parameters

Abstract

We use the complex $\phi^4$ field at finite density as a model system for developing further techniques based on worldline formulations of lattice field theories. More specifically we: 1) Discuss new variants of the worm algorithm for updating the $\phi^4$ theory and related systems with site weights. 2) Explore the possibility of canonical simulations in the worldline formulation. 3) Study the connection of 2-particle condensation at low temperature to scattering parameters of the theory.