Dynamical dark energy from observations

J. Alberto Vázquez (ICF-UNAM)

RESUMEN: A flat Friedmann-Robertson-Walker universe dominated by a cosmological constant (Lambda) and cold dark matter (CDM) has been the working model preferred by cosmologists since the discovery of cosmic acceleration. However, tensions of various degrees of significance are known to be present among existing datasets within the Lambda-CDM framework. In particular, the Lyman-alpha forest measurement of the baryon acoustic oscillations (BAO) by the Baryon Oscillation Spectroscopic Survey prefers a smaller value of the matter density fraction OmegaM than that preferred by cosmic microwave background (CMB). Also, the recently measured value of the Hubble constant, H0 = 73.24 plus-minus 1.74 km s-1 Mpc-1 is 3.4 sigma higher than the 66.93 plus-minus 0.62 km s-1 Mpc-1 inferred from the Planck CMB data. In this work, we investigate whether these tensions can be interpreted as evidence for a non-constant dynamical dark energy.