An extensive universe avoids phantom dark energy
arXiv:2506.05423
Abstract
A major challenge in cosmology and astrophysics is the phantom dark energy used to explain the data of DESI DR2 BAO. Assuming that the degrees of freedom of the universe are (d=3) extensive, we find that the linearised Hubble parameter in Tsallis Entropic cosmology is consistent with Cosmic Chronometers (CC) and DESI DR2 data upto z<2.33, avoiding the need for phantom energy while keeping the observed CMB acoustic angular scale constraint. It also obviates the need for a significant density of CDM.
24 pages, 1 figure