
The bispectrum statistic in the era of precision cosmology
Abstract: As our observational capabilities advance with stage-IV surveys such as DESI, now is a key moment to push beyond traditional two-point statistics to extract more information from the cosmic density field. We present the first joint analysis involving power spectrum and bispectrum of the DESI Data Release 1. We are able to constrain the logarithmic growth rate of structure f and the amplitude of matter fluctuations sigma_s8 separately, which are degenerate in analyses only involving two-point statistics. By fitting the full-shape of the power spectrum and bispectrum on observations of Luminous Red Galaxies and quasars, spanning a redshift range of 0.4 Tribunal: President: Dr. Julián Bautista Secretary: Dr. Fréderic Courbin Vocal: Dr. José Luis Bernal Mera Suplents: Dr. Andreu Font Ribera Dr. Álex Alarcón González Directors: Dra. Licia Verde i Dr. Héctor Gil Marín Tutor: Dr. Alberto Manrique Oliva