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Arxiv: The Excess of JWST Bright Galaxies: a Possible Origin in the Ground State of Dynamical Dark Energy in the light of DESI 2024 Data Published: 10/30/2024 1:51:40 PM Updated: 10/30/2024 1:51:40 PM

Paper abstract: Recent observations by JWST yield a large abundance of luminous galaxies atz\gtrsim 10 compared to that expected in the CDM scenario based onextrapolations of the star formation efficiency measured at lower redshifts.While several astrophysical processes can be responsible for such observations,here we explore to what extent such an effect can be rooted in the assumed DarkEnergy (DE) sector of the current cosmological model. This is motivated byrecent results from different cosmological probes combined with the last datarelease of the Dark Energy Spectroscopic Instrument (DESI), which indicate atension in the DE sector of the concordance {\Lambda} CDM model. We haveconsidered the effect of assuming a DE characterized by a negative {\Lambda} asthe ground state of a quintessence field on the galaxy luminosity function (LF)at high redshifts. We find that such models naturally affect the galaxy UVluminosities in the redshift range 10 <~ z<~ 15 needed to matchthe JWST observations, and with the value of {\Omega}_{\Lambda}=[-0.6,-0.3]remarkably consistent with that required by independent cosmological probes. Asharp prediction of such models is the steep decline of the abundance of brightgalaxies in the redshift range 15 <~ z<~ 16.