Dark-matter content of high-redshift massive galaxies

Determine whether high-redshift massive galaxies have lower dark-matter masses than nearby galaxies.

Background

The paper contrasts nearby-galaxy measurements, which use stellar kinematics and extended tracers, with high-redshift measurements based primarily on ionized-gas kinematics. High-redshift inferences are affected by beam smearing, gas perturbations, and uncertain pressure corrections.

The authors note that the relative dark-matter content of massive galaxies at high redshift versus the nearby Universe remains unsettled. This question is presented as background motivation and is not resolved by the nearby-galaxy sample analyzed in the paper.