Anže Slosar: Measuring the large-scale structure of the Universe at redshifts above 2
Brookhaven National Laboratory, Upton, NY
The Lyman-alpha forest is a series of absorption features in the spectra
of distant quasars, blue-ward of the Lyman-alpha emission line. These
features arise as the light from the quasar is absorbed by the
intervening neutral hydrogen. This gives one-dimensional information
about the fluctuations in the neutral hydrogen density along the line of
sight to the quasar. When spectra of many quasars are combined, it
allows one to build a three-dimensional image of the fluctuations in the
neutral hydrogen density and thus infer the corresponding fluctuations
in the matter density. This makes the Lyman-alpha forest a unique probe
of the distant Universe, opening a novel window on understanding dark
energy, dark matter, neutrino properties and inflation. BOSS experiment
has detected, for the first time, correlations in the Lyman-alpha forest
fluctuations to cosmological distances. It will measure around 160,000
high redshift quasars and constrain dark energy. BigBOSS will be even
fierecer and measure spectra of around a million high-redshift quasars.
