Evolving Dark Energy or Evolving Dark Matter?
Cosmology and Nongalactic Astrophysics
2025-07-22 v2 High Energy Physics - Phenomenology
High Energy Physics - Theory
Abstract
We show that the latest empirical constraints on cosmology, from a combination of DESI, CMB and supernova data, can be accounted for if a small component of dark matter has an evolving and oscillating equation of state within . From a fundamental physics perspective, this interpretation is more appealing than an evolving phantom dark energy with , which violates the null energy condition.
Cite
@article{arxiv.2505.02645,
title = {Evolving Dark Energy or Evolving Dark Matter?},
author = {Xingang Chen and Abraham Loeb},
journal= {arXiv preprint arXiv:2505.02645},
year = {2025}
}
Comments
v2: 21 pages; discussions in Sec.4 and Sec.5 extended, and other minor revisions