Dynamical QCD simulation with theta terms

TL;DR

This paper introduces a method for simulating dynamical QCD with theta terms by using an imaginary theta to enable Monte Carlo sampling, and measures the neutron's electric dipole moment under these conditions.

Contribution

It presents a novel approach to include theta terms in dynamical QCD simulations and explores their effects, including NEDM measurement.

Findings

Successful simulation with imaginary theta enables NEDM measurement.

Demonstrates feasibility of studying theta term effects in dynamical QCD.

Discusses potential applications of theta terms in QCD studies.

Abstract

The theta term that breaks the Strong CP symmetry is introduced in the two flavors of dynamical QCD simulation. theta is analytically continued to a pure imaginary number to make the probability of Monte Carlo positive. The Neutron's Electric Dipole Moment (NEDM) is measured on the ensemble under a uniform and week electric field. Other applications of theta terms are also discussed.