Iosifidis, D; Jensko, E; Koivisto, TS; (2024) Relativistic interacting fluids in cosmology. Journal of Cosmology and Astroparticle Physics , 2024 (11) , Article 043. 10.1088/1475-7516/2024/11/043.

Text 2406.01412v1.pdf - Accepted Version Access restricted to UCL open access staff until 27 November 2025. Download (630kB)

Abstract

Motivated by cosmological applications for interacting matters, an extension of the action functional for relativistic fluids is proposed to incorporate the physics of non-adiabatic processes and chemical reactions. The former are characterised by entropy growth, while the latter violate particle number conservation. The relevance of these physics is demonstrated in the contexts of self-interacting fluids, fluids interacting with scalar fields, and hyperhydrodynamical interactions with geometry. The possible cosmological applications range from early-universe phase transitions to astrophysical phenomena, and from matter creation inflationary alternatives to interacting dark sector alternatives to the ΛCDM model that aim to address its tensions. As an example of the latter, a single fluid model of a unified dark sector is presented. The simple action of the model features one field and one parameter, yet it can both reproduce the ΛCDM cosmology and predict new phenomenology.

Download activity - last month

Export as CSVXMLJSON

Download activity - last 12 months

Export as JSONXMLCSV

Downloads by country - last 12 months

Export as JSONXMLCSV

Archive Staff Only

View Item