First experience with classical-statistical real-time simulations of anomalous transport with overlap fermions

TL;DR

This paper demonstrates that overlap fermions in classical-statistical real-time simulations more accurately reproduce the anomaly equation and anomalous transport phenomena than Wilson-Dirac fermions, especially under dynamic electromagnetic fields.

Contribution

It introduces the first real-time simulation results using overlap fermions for anomalous transport, showing improved accuracy over Wilson-Dirac fermions on smaller lattices.

Findings

Overlap fermions reproduce the anomaly equation more precisely than Wilson-Dirac fermions.

Overlap fermions perform better even on smaller lattices.

Results are consistent under dynamic electromagnetic fields and back-reaction effects.

Abstract

We present first results of classical-statistical real-time simulations of anomalous transport phenomena with overlap fermions. We find that even on small lattices overlap fermions reproduce the real-time anomaly equation with much better precision than Wilson-Dirac fermions on an order of magnitude larger lattices. The difference becomes much more pronounced for quickly changing electromagnetic fields, especially if one takes into account the back-reaction of fermions on electromagnetism. As test cases, we consider chirality pumping in parallel electric and magnetic fields and mixing between the plasmon and the Chiral Magnetic Wave.