Constraints on prospective deviations from the cold dark matter model using a Gaussian process

Recently, using Bayesian Machine Learning, a deviation from the cold dark matter model on cosmological scales has been put forward. Such a model might replace the proposed non-gravitational interaction between dark energy and dark matter, and help solve the 0 tension problem. The idea behind the lea...

Descripción completa

Detalles Bibliográficos
Autores: Khurshudyan, Martiros, Elizalde, Emilio
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/362733
Acceso en línea:http://hdl.handle.net/10261/362733
Access Level:acceso abierto
Palabra clave:H0 tension
Bayesian machine learning
Gaussian processes
Descripción
Sumario:Recently, using Bayesian Machine Learning, a deviation from the cold dark matter model on cosmological scales has been put forward. Such a model might replace the proposed non-gravitational interaction between dark energy and dark matter, and help solve the 0 tension problem. The idea behind the learning procedure relies on a generated expansion rate, while the real expansion rate is just used to validate the learned results. In the present work, however, the emphasis is put on a Gaussian Process (GP), with the available () data confirming the possible existence of the already learned deviation. Three cosmological scenarios are considered: a simple one, with an equation-of-state parameter for dark matter =0≠0, and two other models, with corresponding parameters =0+1 and =0+1/(1+). The constraints obtained on the free parameters 0 and 1 hint towards a dynamical nature of the deviation. The dark energy dynamics is also reconstructed, revealing interesting aspects connected with the 0 tension problem. It is concluded, however, that improved tools and more data are needed, to reach a better understanding of the reported deviation.