DESI 2024: Constraints on physics-focused aspects of dark energy using DESI DR1 BAO data
K. Lodha, A. Shafieloo, R. Calderón, E. Linder, Wuhyun Sohn, Jorge L. Cervantes–Cota, Arnaud de Mattia, J. García-Bellido, M Ishak, William L. Matthewson, José Aguilar, S. Ahlen, David H. Brooks, T. Claybaugh, Axel de la Macorra, A. Dey, Biprateep Dey, P. Doel, J. E. Forero-Romero, E. Gaztañaga, Satya Gontcho A Gontcho, Cullan Howlett, S. Juneau, S. Kent, T. Kisner, Adam Lambert, M. Landriau, L. Le Guillou, Paul Martini, Aaron Meisner, R. Miquel, John Moustakas, J. A. Newman, G. Niz, N. Palanque‐Delabrouille, Will J. Percival, Claire Poppett, Francisco Prada, Graziano Rossi, V. Ruhlmann-Kleider, E. Sánchez, Edward F. Schlafly, D. Schlegel, M. Schubnell, Hee‐Jong Seo, David Sprayberry, G. Tarlé, B. A. Weaver, H. Zou
Abstract
Baryon acoustic oscillation data from the first year of the Dark Energy Spectroscopic Instrument (DESI) provide near percent-level precision of cosmic distances in seven bins over the redshift range $z=0.1--4.2$. This paper is the follow-up to the original DESI BAO cosmology paper [A. G. Adame et al. (DESI Collaboration), arXiv:2404.03002], which considered the conventional ${w}_{0}{w}_{a}$ cold dark matter (CDM) model. We use the novel DESI data, together with other cosmic probes, to constrain the background expansion history using some well-motivated physical classes of dark energy. In particular, we explore three physics-focused behaviors of dark energy from the equation of state and energy density perspectives: the thawing class (matching many simple quintessence potentials), emergent class (where dark energy comes into being recently, as in phase transition models), and mirage class [where phenomenologically the distance to cosmic microwave background (CMB) last scattering is close to that from a cosmological constant $\mathrm{\ensuremath{\Lambda}}$ despite dark energy dynamics]. All three classes fit the data at least as well as $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$, and indeed can improve on it by $\mathrm{\ensuremath{\Delta}}{\ensuremath{\chi}}^{2}\ensuremath{\approx}\ensuremath{-}5$ to $\ensuremath{-}17$ for the combination of DESI BAO with CMB and supernova data while having one more parameter. The mirage class does essentially as well as ${w}_{0}{w}_{a}\mathrm{CDM}$ and exhibits moderate to strong Bayesian evidence preference with respect to $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$. These classes of dynamical behaviors highlight worthwhile avenues for further exploration into the nature of dark energy.