Hot dense magnetized spinor matter in particle and astroparticle physics: the role of boundaries

TL;DR

This paper investigates how boundaries affect chiral effects in hot, dense, magnetized spinor matter, revealing that boundaries can suppress or enhance effects like the chiral magnetic and separation effects, with implications for astrophysics and condensed matter.

Contribution

It provides a comprehensive analysis of boundary conditions on chiral effects in relativistic matter under strong magnetic fields, highlighting the boundary-dependent behavior of these effects.

Findings

Chiral magnetic effect disappears with boundaries.

Chiral separation effect persists and depends on temperature and boundary conditions.

Boundary conditions can amplify or diminish chiral effects, even at zero chemical potential.

Abstract

We study the influence of boundaries on chiral effects in hot dense relativistic spinor matter in a strong magnetic field which is orthogonal to the boundaries. The most general set of boundary conditions ensuring the confinement of matter within the boundaries is employed. We find that the chiral magnetic effect disappears, whereas the chiral separation effect stays on, becoming dependent on temperature and on a choice of boundary conditions. As temperature increases from zero to large values, a stepped-shape behaviour of the chiral separation effect as a function of chemical potential is changed to a smooth one. A choice of the boundary condition can facilitate either amplification or diminution of the chiral separation effect; in particular, the effect can persist even at zero chemical potential, if temperature is finite. This points at a significant role of boundaries for physical systems with hot dense magnetized spinor matter, i.e. compact astrophysical objects (neutron stars and magnetars), relativistic heavy-ion collisions, novel materials known as the Dirac and Weyl semimetals.