Dynamical Relaxation States in SPARC Galaxies from an Effective Viscoelastic Framework

This work investigates the residual structure of the Radial Acceleration Relation (RAR) in galaxies using the SPARC sample within the framework of an Effective Viscoelastic Model (EVM). Rather than interpreting the RAR scatter as purely stochastic noise, this study explores the possibility that residual structures encode physically meaningful information about galaxy dynamical relaxation states. Using 175 SPARC galaxies, an emergent effective relaxation parameter is inferred and statistically analyzed against galaxy kinematics and morphology. Statistically significant correlations are identified between the inferred relaxation states and maximum rotation velocity, effective dynamical indicators, and broad morphological classes. The results suggest that galaxy-scale gravitational phenomenology may exhibit non-equilibrium collective response behavior, where the observed RAR scatter reflects incomplete or scale-dependent dynamical relaxation processes. This work presents a phenomenological exploration of galaxy relaxation-state structures and provides a possible dynamical interpretation of RAR residuals within an effective delayed-response gravitational framework.