Chiral asymmetry of the Fermi surface in dense relativistic matter in a magnetic field

TL;DR

This paper uncovers a dynamical contribution to the axial current in dense relativistic matter under magnetic fields, caused by a shift in Fermi surfaces of opposite chirality fermions, impacting astrophysical and collider phenomena.

Contribution

It identifies a new dynamical axial current contribution affecting all Landau levels, distinct from previously known topological effects, with implications for dense matter physics.

Findings

Dynamical axial current exists in interacting matter.

Fermi surface shifts differ for left- and right-handed fermions.

Impacts transport and emission in astrophysical and collider environments.

Abstract

It is revealed that in dense relativistic matter in a magnetic field, there exists a contribution to the axial current associated with a relative shift of the longitudinal momenta in the dispersion relations of opposite chirality fermions. Unlike the topological contribution in the axial current at the lowest Landau level, recently discussed in the literature, the dynamical one appears only in interacting matter and affects the fermions in all Landau levels, including those around the Fermi surface. The induced axial current and the shift of the Fermi surfaces of the left-handed and right-handed fermions are expected to play an important role in transport and emission properties of matter in various types of compact stars as well as in heavy ion collisions.