Running Vacuum Cosmology in f(R,T) Gravity: Observational Constraints and Thermodynamic Analysis
Abstract
Despite the remarkable observational success of the ΛCDM model, the physical origin of dark energy and the cosmological constant remain unresolved, motivating the exploration of dynamical vacuum scenarios within modified theories of gravity. Inspired by the quantum field theoretical description of running vacuum energy, we investigate a running vacuum cosmology in the framework of linear f(R,T)=R+λT gravity. Unlike recent studies that establish an effective correspondence between running vacuum energy and modified gravity, our approach directly incorporates a quantum field theory motivated running vacuum scenario into the f(R,T) framework and examines its cosmological implications. Exact analytical solutions of the modified field equations are obtained in a spatially flat Friedmann--Lemaître--Robertson--Walker spacetime, yielding an analytical expression for the Hubble parameter. The free model parameters are constrained using the latest Pantheon+SH0ES compilation, DESI baryon acoustic oscillation measurements, and their joint dataset through Markov Chain Monte Carlo analysis. The observationally constrained model successfully reproduces the observed expansion history, remains consistent with independent Cosmic Chronometer measurements, predicts an age of the universe within current observational bounds, and yields an effective equation of state compatible with current observations. Furthermore, the statefinder and Om diagnostics indicate close agreement with the ΛCDM scenario at late times, while the generalized second law of thermodynamics remains valid throughout cosmic evolution. These results demonstrate that the proposed framework provides an observationally viable and thermodynamically consistent realization of running vacuum cosmology in f(R,T) gravity, offering a theoretically motivated alternative for describing the present accelerated universe.
Related
- Theoretical consistency and observational constraints on entropic cosmology
- Hybrid Expansion Cosmology in f(T) Gravity: Late-Time Evolution and Observational Bounds
- Gravitational Wave Propagation in K-essence Cosmology: Theory and Observational Constraints
- Theoretical Consistency and Observational Constraints on Entropic Cosmology
- Kruglov-entropy cosmology from apparent-horizon thermodynamics: background dynamics and observational constraints
BibTeX
@misc{anjani2026running,
title = {{Running Vacuum Cosmology in f(R,T) Gravity: Observational Constraints and Thermodynamic Analysis}},
author = {Anjani and Ajay Kumar and Pinki and Pankaj Kumar},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.01632},
eprint = {2609.01632},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.01632},
}
RIS
TY - UNPB
TI - Running Vacuum Cosmology in f(R,T) Gravity: Observational Constraints and Thermodynamic Analysis
AU - Anjani
AU - Ajay Kumar
AU - Pinki
AU - Pankaj Kumar
PY - 2026
DA - 2026/09/01
PB - arXiv
DO - 10.48550/arxiv.2609.01632
UR - https://arxiv.org/abs/2609.01632
AB - Despite the remarkable observational success of the ΛCDM model, the physical origin of dark energy and the cosmological constant remain unresolved, motivating the exploration of dynamical vacuum scenarios within modified theories of gravity. Inspired by the quantum field theoretical description of running vacuum energy, we investigate a running vacuum cosmology in the framework of linear f(R,T)=R+λT gravity. Unlike recent studies that establish an effective correspondence between running vacuum energy and modified gravity, our approach directly incorporates a quantum field theory motivated running vacuum scenario into the f(R,T) framework and examines its cosmological implications. Exact analytical solutions of the modified field equations are obtained in a spatially flat Friedmann--Lemaître--Robertson--Walker spacetime, yielding an analytical expression for the Hubble parameter. The free model parameters are constrained using the latest Pantheon+SH0ES compilation, DESI baryon acoustic oscillation measurements, and their joint dataset through Markov Chain Monte Carlo analysis. The observationally constrained model successfully reproduces the observed expansion history, remains consistent with independent Cosmic Chronometer measurements, predicts an age of the universe within current observational bounds, and yields an effective equation of state compatible with current observations. Furthermore, the statefinder and Om diagnostics indicate close agreement with the ΛCDM scenario at late times, while the generalized second law of thermodynamics remains valid throughout cosmic evolution. These results demonstrate that the proposed framework provides an observationally viable and thermodynamically consistent realization of running vacuum cosmology in f(R,T) gravity, offering a theoretically motivated alternative for describing the present accelerated universe.
ER -