Exponential quintessence: curved, steep and stringy?

Author:

Andriot DavidORCID,Parameswaran SushaORCID,Tsimpis DimitriosORCID,Wrase TimmORCID,Zavala IvonneORCID

Abstract

Abstract We explore the possibility that our universe’s current accelerated expansion is explained by a quintessence model with an exponential scalar potential, V = V0e−λ ϕ, keeping an eye towards λ$$ \sqrt{2} $$ 2 and an open universe, favorable to a string theory realisation and with no cosmological horizon. We work out the full cosmology of the model, including matter, radiation, and optionally negative spatial curvature, for all λ > 0, performing an extensive analysis of the dynamical system and its phase space. The minimal physical requirements of a past epoch of radiation domination and an accelerated expansion today lead to an upper bound λ$$ \sqrt{3} $$ 3 , which is driven slightly up in the presence of observationally allowed spatial curvature. Cosmological solutions start universally in a kination epoch, go through radiation and matter dominated phases and enter an epoch of acceleration, which is only transient for λ > $$ \sqrt{2} $$ 2 . Field distances traversed between BBN and today are sub-Planckian. We discuss possible string theory origins and phenomenological challenges, such as time variation of fundamental constants. We provide theoretical predictions for the model parameters to be fitted to data, most notably the varying dark energy equation of state parameter, in light of recent results from DES-Y5 and DESI.

Publisher

Springer Science and Business Media LLC

Reference77 articles.

1. B. Ratra and P.J.E. Peebles, Cosmological Consequences of a Rolling Homogeneous Scalar Field, Phys. Rev. D 37 (1988) 3406 [INSPIRE].

2. P.J.E. Peebles and B. Ratra, Cosmology with a Time Variable Cosmological Constant, Astrophys. J. Lett. 325 (1988) L17 [INSPIRE].

3. R.R. Caldwell, R. Dave and P.J. Steinhardt, Cosmological imprint of an energy component with general equation of state, Phys. Rev. Lett. 80 (1998) 1582 [astro-ph/9708069] [INSPIRE].

4. E. Abdalla et al., Cosmology intertwined: A review of the particle physics, astrophysics, and cosmology associated with the cosmological tensions and anomalies, JHEAp 34 (2022) 49 [arXiv:2203.06142] [INSPIRE].

5. DES collaboration, The Dark Energy Survey: Cosmology Results With ~ 1500 New High-redshift Type Ia Supernovae Using The Full 5-year Dataset, arXiv:2401.02929 [INSPIRE].

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