Chirality in Astrophysics

TL;DR

This paper reviews how chirality appears in astrophysics through magnetic structures, fundamental particle interactions, and spontaneous symmetry breaking, highlighting their mechanisms and implications.

Contribution

It provides a comprehensive comparison of three distinct mechanisms of chirality emergence in astrophysical contexts and related fields.

Findings

Magnetic helicity exhibits hemispheric systematic twist.

Chirality at the microphysical level links to weak force parity violation.

Spontaneous chirality arises via instabilities and nonlinear processes.

Abstract

Chirality, or handedness, enters astrophysics in three distinct ways. Magnetic field and vortex lines tend to be helical and have a systematic twist in the northern and southern hemispheres of a star or a galaxy. Helicity is here driven by external factors. Chirality can also enter at the microphysical level and can then be traced back to the parity-breaking weak force. Finally, chirality can arise spontaneously, but this requires not only the presence of an instability, but also the action of nonlinearity. Examples can be found both in magnetohydrodynamics and in astrobiology, where homochirality among biomolecules probably got established at the origin of life. In this review, all three types of chirality production will be explored and compared.