https://doi.org/10.1140/epjc/s10052-025-15227-1
Regular Article - Theoretical Physics
Cosmological dynamics of matter creation with modified Chaplygin gas and bulk viscosity
Department of Applied Mathematics, Delhi Technological University, Bawana Road, 110042, Delhi, India
a
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Received:
2
October
2025
Accepted:
14
December
2025
Published online:
24
December
2025
Abstract
This work presents a comprehensive investigation of a novel cosmological model that includes the Modified Chaplygin Gas (MCG) equation of state with gravitationally induced matter creation and bulk viscous dissipation in a spatially flat Friedmann–Lemaître–Robertson–Walker spacetime. The MCG fluid is characterized by an exotic equation of state 
. The matter creation rate is taken as 
and the bulk viscous pressure as 
. We derive the modified Friedmann equations and obtain an analytical expression for the Hubble parameter H(z), which is then used to reconstruct the evolutionary trajectories of key cosmological parameters. The model parameters are constrained using two observational datasets: DS1 (Pantheon+ + Cosmic Chronometers + DESI BAO + 
) and DS2 (DS1 + R22). Our results indicate that the proposed hybrid model successfully generates a transition from decelerated to accelerated expansion, consistent with current observations. Notably, when the R22 prior is included the best-fit value of 
shifts towards the local SH0ES determination; the hybrid model is flexible enough to accommodate this higher while preserving a good fit to the geometric datasets, thereby reducing the level of tension in joint analyses between local and background probes, although it does not dynamically resolve the discrepancy by itself. Furthermore, we perform a rigorous thermodynamic analysis of the model by testing the Generalized Second Law (GSL) of thermodynamics. We use the information cretria, like Akaike and Bayesian to check the model stability. This work establishes a physically motivated, observationally viable, and thermodynamically consistent alternative to the standard 
CDM paradigm.
© The Author(s) 2025
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Funded by SCOAP3.
