English

Do cosmological observations allow a negative $\Lambda$?

Cosmology and Nongalactic Astrophysics 2022-10-26 v2 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory

Abstract

In view of the recent measurement of H0H_{0} from HST and SH0ES team, we explore the possibility of existence of a negative cosmological constant (AdS vacua in the dark energy sector) in the Universe. In this regard, we consider quintessence fields on top of a negative cosmological constant and compare such construction with Λ\LambdaCDM model using a different combination of CMB, SnIa, BAO and H0H_{0} data. Various model comparison estimators show that quintessence models with a negative Λ\Lambda is either preferred over Λ\LambdaCDM or performs equally as Λ\LambdaCDM model. This suggests that the presence of a negative Λ\Lambda (AdS ground state) in our Universe, which can naturally arise in string theory, is consistent with cosmological observations.

Keywords

Cite

@article{arxiv.2112.10641,
  title  = {Do cosmological observations allow a negative $\Lambda$?},
  author = {Anjan A. Sen and Shahnawaz A. Adil and Somasri Sen},
  journal= {arXiv preprint arXiv:2112.10641},
  year   = {2022}
}

Comments

9 pages, Latex style, 6 figures, 6 tables, Revised version with new discussions and results, Accepted for publication in MNRAS

R2 v1 2026-06-24T08:24:48.947Z