Observational search for primordial chirality violations using galaxy angular momenta

TL;DR

This study investigates whether primordial chirality violations can be detected through galaxy angular momentum correlations, finding no significant evidence for such violations within current observational uncertainties.

Contribution

It introduces a novel method of comparing galaxy spin directions with helical components of initial density perturbations to test for primordial chirality violation.

Findings

Galaxy spins show no significant correlation with helical components, consistent with no primordial chirality violation.

Right helical component correlation is ruled out at about 3.8σ, constraining certain models.

Current data cannot definitively exclude maximal primordial chirality violation.

Abstract

We search for evidence of primordial chirality violation in the galaxy data from the Sloan Digital Sky Survey by comparing how strongly directions of galaxy angular momenta correlate with left and right helical components of a spin vector field constructed from the initial density perturbations. Within uncertainties, galaxy spins correlate with these two helical components identically, which is consistent with Universe without primordial chirality violation. Given current data, it is not yet possible to rule out maximal chiral violation, although the case of vanishing correlation with the right helical component is ruled out at about 3.8$\sigma$.