IA/U.Lisboa Seminar - The price of shifting the Hubble Constant and evidence for dark energy evolution - 09 julho 2018

The current tension in H0 measurements by Planck-2015 for ΛCDM and that by recent direct measurement by Riess et al. 2016, also results another tension in the value of rd, the sound horizon at drag epoch, measured by BAO observations and Planck-2015. We show that, regardless of dark energy dynamics, to accommodate higher value of H0, one needs a lower value of rd, and so necessarily a modification of early universe cosmology. Later on, a model independent approach to constraint background evolution of the universe with low-redshift data, will be discussed.