Conformal anomaly and helicity effects in kinetic theory via scale-dependent coupling

Chernodub M. N. , Kilincarslan E.

PHYSICAL REVIEW D, vol.103, no.3, 2021 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 103 Issue: 3
  • Publication Date: 2021
  • Doi Number: 10.1103/physrevd.103.036019
  • Title of Journal : PHYSICAL REVIEW D


We modify a kinetic theory of massless fermions to incorporate the effects of the conformal anomaly. Working in a collisionless regime, we emulate the conformal anomaly via a momentum-dependent electric coupling. In this prescription, the conformal anomaly leads to a hedgehoglike structure in the momentum space similar to the Berry phase associated with the axial anomaly. The interplay between the axial and conformal anomalies generates the axial current, proportional to the helicity flow of the electromagnetic background. The corresponding conductivity is determined by the running of the electric coupling between the tip of the Dirac cone and the Fermi surface.