Energy Density Functional of Confined Quarks: an Improved Ansatz

Udita Shukla; Pok Man Lo

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arXiv · 2504.01814

Energy Density Functional of Confined Quarks: an Improved Ansatz

Udita Shukla·Pok Man Lo

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Abstract

Density Functional Theory (DFT) is a robust framework for modeling interacting many-body systems, including the equation of state (EoS) of dense matter. Many models, however, rely on energy functionals based on assumptions that have not been rigorously validated. We critically analyze a commonly used ansatz for confinement, where the energy functional scales with density as $U \propto n^{\frac{2}{3}}$ . Our findings, derived from a systematic non-local energy functional, reveal that this scaling does not capture the dynamics of confinement. Instead, the energy functional evolves from $n^2$ at low densities to $n$ at high densities, governed by an infrared cutoff. These results suggest that models relying on such assumptions should be revisited to ensure more reliable EoS construction.

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Udita Shukla, Pok Man Lo. 2025-04-02. Energy Density Functional of Confined Quarks: an Improved Ansatz. https://arxiv.org/abs/2504.01814

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