Resolve higher-order pseudogauge effects in spin hydrodynamics

Resolve the higher-order pseudogauge subtleties that arise beyond the first-order hydrodynamic-gradient truncation in the Belinfante-Rosenfeld formulation of hyperon polarization with scalar GUP phase-space deformations.

Background

The analysis fixes the Belinfante-Rosenfeld pseudogauge and truncates the hydrodynamic expansion at first order in gradients. The paper notes that pseudogauge transformations can be reinterpreted as field redefinitions at second order, but does not analyze the resulting effects on the local-equilibrium operator or polarization observable.

A resolution would be needed to determine whether the covariance-based GUP correction and the local cancellation of the scalar phase-space factor remain valid when higher-order gradient and pseudogauge effects are included.

References

Pseudo gauge transformations play a central role in hydrodynamics with spin degrees of freedom. Their implications for local thermodynamics and higher-order transport have been analyzed in detail, including how pseudo gauge changes can be reinterpreted as field redefinitions at second order in gradients . Since the present paper truncates at first order in gradients, these higher-order subtleties are not resolved here, and the pseudo gauge must be fixed as part of the definition of the effective theory.

— Minimal-Length Corrections to Hyperon Polarization in Rotating Quark Gluon Plasma  (2610.12128 - Pourhassan et al., 8 Oct 2026) in Section 8, Conceptual Consistency