DESI 2024: reconstructing dark energy using crossing statistics with DESI DR1 BAO data

R Calderon, K Lodha, A Shafieloo… - … of Cosmology and …, 2024 - iopscience.iop.org
R Calderon, K Lodha, A Shafieloo, E Linder, W Sohn, A de Mattia, JL Cervantes-Cota
Journal of Cosmology and Astroparticle Physics, 2024iopscience.iop.org
Abstract We implement Crossing Statistics to reconstruct in a model-agnostic manner the
expansion history of the universe and properties of dark energy, using DESI Data Release 1
(DR1) BAO data in combination with one of three different supernova compilations
(PantheonPlus, Union3, and DES-SN5YR) and Planck CMB observations. Our results hint
towards an evolving and emergent dark energy behaviour, with negligible presence of dark
energy at z≳ 1, at varying significance depending on data sets combined. In all these …
Abstract
We implement Crossing Statistics to reconstruct in a model-agnostic manner the expansion history of the universe and properties of dark energy, using DESI Data Release 1 (DR1) BAO data in combination with one of three different supernova compilations (PantheonPlus, Union3, and DES-SN5YR) and Planck CMB observations. Our results hint towards an evolving and emergent dark energy behaviour, with negligible presence of dark energy at z≳ 1, at varying significance depending on data sets combined. In all these reconstructions, the cosmological constant lies outside the 95% confidence intervals for some redshift ranges. This dark energy behaviour, reconstructed using Crossing Statistics, is in agreement with results from the conventionalw 0–w a dark energy equation of state parametrization reported in the DESI Key cosmology paper. Our results add an extensive class of model-agnostic reconstructions with acceptable fits to the data, including models where cosmic acceleration slows down at low redshifts. We also report constraints on H 0 r d from our model-agnostic analysis, independent of the pre-recombination physics.
iopscience.iop.org