Viscous Ghost Dark Energy in f(Q, Lm) Gravity: Observational and Thermodynamic Validity
Abstract
We investigate the cosmological implications of viscous ghost dark energy in the framework of modified f(Q,ℒm) gravity by considering the linear functional form f(Q,ℒm)=αQ+βℒm. The non-minimal coupling between geometry and matter together with bulk viscous effects modifies the cosmic dynamics, leading to an analytical solution of the background Friedmann equations. Since the expansion history depends only on effective combinations of the model parameters, the observational analysis is performed in terms of the corresponding effective background parameters. We constrain the model using the latest joint compilation of Pantheon+ including SH0ES Type Ia supernovae, Cosmic Chronometers, and DESI baryon acoustic oscillation measurements. The model provides a satisfactory description of the late-time expansion history and reproduces the observed transition from decelerated to accelerated cosmic expansion. A statistical comparison with the standard ΛCDM model is performed using the minimum χ2, Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC). Furthermore, the thermodynamic viability of the model is examined through the evolution of the total entropy, and the generalized second law of thermodynamics is found to remain valid throughout the cosmic evolution.
Related
- Thermodynamic Stability of a Viscous Variable Generalised Chaplygin Gas
- Analog Gravity in Magneto-Viscous Fluids: Enhanced Analog Hawking Temperature in Accretion Disks
- Viscous matter in modified f(R)-gravity: Hubble tension attenuation with DESI and SH0ES data
- Role of viscous fluid in FLRW model with observational constraints
- Charged Black Hole Solution in Hoyle Narlikar Gravity and its Thermodynamic Properties
BibTeX
@misc{kumar2026viscous,
title = {{Viscous Ghost Dark Energy in $f(Q, L_m)$ Gravity: Observational and Thermodynamic Validity}},
author = {Ajay Kumar and Pankaj Kumar},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.07069},
eprint = {2610.07069},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.07069},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Viscous Ghost Dark Energy in f(Q, L_m) Gravity: Observational and Thermodynamic Validity
AU - Ajay Kumar
AU - Pankaj Kumar
PY - 2026
DA - 2026/10/05
PB - arXiv
DO - 10.48550/arxiv.2610.07069
UR - https://arxiv.org/abs/2610.07069
AB - We investigate the cosmological implications of viscous ghost dark energy in the framework of modified f(Q,ℒ_m) gravity by considering the linear functional form f(Q,ℒ_m)=αQ+βℒ_m. The non-minimal coupling between geometry and matter together with bulk viscous effects modifies the cosmic dynamics, leading to an analytical solution of the background Friedmann equations. Since the expansion history depends only on effective combinations of the model parameters, the observational analysis is performed in terms of the corresponding effective background parameters. We constrain the model using the latest joint compilation of Pantheon+ including SH0ES Type Ia supernovae, Cosmic Chronometers, and DESI baryon acoustic oscillation measurements. The model provides a satisfactory description of the late-time expansion history and reproduces the observed transition from decelerated to accelerated cosmic expansion. A statistical comparison with the standard ΛCDM model is performed using the minimum χ^2, Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC). Furthermore, the thermodynamic viability of the model is examined through the evolution of the total entropy, and the generalized second law of thermodynamics is found to remain valid throughout the cosmic evolution.
ER -