Thermodynamics, Relativistic Mean Field Modeling, and Transport for Neutron Star Matter. A Self-Consistent Framework for Equations of State, Opacities, and Uncertainty Quantification

https://doi.org/10.65770/FFGL9154

ABSTRACT

            We present a unified, reproducible framework that integrates rigorous thermodynamics, relativistic mean‑field (RMF) theory, neutrino and photon opacity modeling, and uncertainty quantification to construct finite-temperature equations of state (EOS) and transport inputs for neutron‑star applications. The paper derives thermodynamic potentials and response functions with full Legendre‑transform consistency, develops a thermodynamically consistent RMF implementation (including rearrangement terms for density-dependent couplings), and formulates neutrino and radiative opacities with in-medium corrections suitable for tabulation. We demonstrate the pipeline with a working implementation: (i) a zero-temperature RMF EOS computed on a dense baryon‑density grid, (ii) sample EOS and TOV solutions, and (iii) a sensitivity analysis using Sobol indices for three RMF couplings mapping to and . We document numerical checks for Maxwell relations, convexity, causality ( ), and thermodynamic pressure equality. The framework is intended for high‑fidelity neutron‑star modeling, gravitational‑wave interpretation, and neutrino‑radiation hydrodynamics.

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WSN 218 (2026) 106-121

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