Colloquium with Dr. Andreu Font-Riera. How constant is the Cosmological Constant? New evidence for evolving Dark Energy from the DESI collaboration
The Department of Physics and the Institut de Física d'Altes Energies (IFAE) present the colloquium "How constant is the Cosmological Constant? New evidence for evolving Dark Energy from the DESI collaboration" on April 9 at 3 pm at S of the Faculty of Sciences and Biosciences (UAB) with Dr. Andreu Font-Ribera, from the Observational Cosmology Group,IFAE.
Abstract.
Some of the open questions in fundamental physics can be addressed by looking at the distribution of matter in the Universe as a function of scale and time (or redshift). We can study the nature of dark energy, causing the accelerated expansion of the Universe. We can measure the sum of the neutrino masses, and determine its hierarchy. We can test the standard model at energies higher that those accessible at the laboratory, by studying the primordial density perturbations seeded during Inflation.
The Dark Energy Spectroscopic Instrument (DESI) started in 2021 a five-years program to generate the largest and most accurate 3D map of the distribution of galaxies and quasars. By measuring the statistical properties of these catalogs, DESI will be able to reconstruct the expansion history of the Universe over the last 11 billion years, while making precise measurements of the growth of structure.
In this talk I will present the latest cosmological results from DESI, in particular the measurements of the expansion of the Universe using the first three years of DESI data. I will discuss the cosmological implications of these measurements, the significant preference for dynamical dark energy, a model where dark energy is not a constant but changes with time.