Modified gravity in the presence of matter creation: scenario for the late Universe

Abstract

We consider a dynamic scenario for characterizing the late Universe evolution, aiming to mitigate the Hubble tension. Specifically, we consider a metric $f(R)$ gravity in the Jordan frame which is implemented to the dynamics of a flat isotropic Universe. This cosmological model incorporates a matter creation process, due to the time variation of the cosmological gravitational field. We model particle creation by representing the isotropic Universe (specifically, a given fiducial volume) as an open thermodynamic system. The resulting dynamical model involves four unknowns: the Hubble parameter, the non-minimally coupled scalar field, its potential, and the energy density of the matter component. We impose suitable conditions to derive a closed system for these functions of the redshift. In this model, the vacuum energy density of the present Universe is determined by the scalar field potential, in line with the modified gravity scenario. Hence, we construct a viable model, determining the form of the $f(R)$ theory a posteriori and appropriately constraining the phenomenological parameters of the matter creation process to eliminate tachyon modes. Finally, by analyzing the allowed parameter space, we demonstrate that the Planck evolution of the Hubble parameter can be reconciled with the late Universe dynamics, thus alleviating the Hubble tension.

8 pages, 3 figures

References in corpus (8)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Seven hints that early-time new physics alone is not sufficient to solve the Hubble tension
• f(R) Gravity and Chameleon Theories
• On the evolution of the Hubble constant with the SNe Ia Pantheon Sample and Baryon Acoustic Oscillations: a feasibility study for GRB-cosmology in 2030
• Analyzing the $H_0$ tension in $F(R)$ gravity models
• Phantom behavior via cosmological creation of particles
• Cosmic acceleration without dark energy: Background tests and thermodynamic analysis
• Gravitationally induced particle production and its impact on structure formation

Cited by in corpus (3)

• Decay of $f(R)$ quintessence into dark matter: mitigating the Hubble tension?
• Decay of dark energy into dark matter in a metric $f(R)$ gravity: effective running Hubble constant
• Reheating constraints and the $H_0$ tension in Quintessential Inflation