A generalized expression for the relaxation time of dipolar-interacting magnetic nanoparticles is derived by extending the Kramers-Brown escape-rate theory within the Tsallis statistical framework. A coarse-grained microscopic motivation is developed for the fluctuation-dominated superdiffusive regime, whereas the subdiffusive regime is treated as an effective phenomenological description of configurationally confined relaxation in strongly interacting assemblies. The resulting relaxation law describes both slower and faster dynamics relative to the Néel-Brown limit. The experimental systems considered here primarily probe the subdiffusive regime, while the quantitative validation of the microscopic relation proposed for the superdiffusive regime remains an open question. The theory yields a natural kinetic interpretation of the $T_{\mathrm{cutoff}}$ temperature as a characteristic freezing scale associated with configurational confinement, collective slowing down, and glasslike dynamics within the nonextensive framework and Néel-Brown relaxation theory, thereby contributing to ongoing discussions regarding collective slowing down phenomena in interacting nanoparticle systems.

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• Scaling laws of complex systems
• Ferrofluids
• Magnetic colloids
• Magnetic nanoparticles
• Nanoclusters
• Nonlinear time-delay systems
• Spin glasses
• Boltzmann theory
• Brownian dynamics
• Chaos & nonlinear dynamics
• Fokker–Planck equation
• Landau-Lifschitz-Gilbert equation
• Langevin equation
• Semiclassical physics
• Susceptibility measurements