A Cosmological Lever Arm for Fundamental Physics

What is the nature of dark energy that is causing the expansion of the Universe to accelerate? Were the initial conditions of our Universe set by inflation? How much do neutrinos weigh? These open questions in the boundary of cosmology and fundamental physics can be addressed by studying the distribution of matter in the Universe, both as a function of scale, and as a function of time.

While the traditional approach has been to use large galaxy catalogs, during the last decade Andreu Font-Ribera and his collaborators have developed an alternative probe: the Lyman-α (Lyα) forest, absorption features in the spectra of high-redshift quasars caused by neutral hydrogen along the line of sight towards the Earth. The Lyα forest provides a unique window to study the distribution of matter at earlier times and on smaller scales than those accessible with galaxy catalogs.

COSMO-LYA will apply these analysis techniques to obtain results that will have interdisciplinary impact, with wide reaching consequences into particle and fundamental physics.