The Highest-Redshift Balmer Breaks as a Test of ΛCDM

Recent studies have reported tension between the presence of luminous, high-redshift galaxies and the halo mass functions predicted by standard cosmology. Here, an improved test is proposed using the presence of high-redshift Balmer breaks to probe the formation of early 10^4 - 10^5 M_\odot baryonic minihalos. Unlike previous tests, this... Show more