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arXiv · 2601.08054

Magnetic reconnection as an Adler-Ohmic bifurcation: The topological origin of Bohm resistivity

Abstract

The physical origin of 'anomalous' resistivity in magnetic reconnection remains one of the longest-standing problems in space plasma physics. While the empirical Bohm diffusion scaling ($η\propto T/B$) is widely invoked to explain fast reconnection rates, it lacks a rigorous derivation from first principles. Here, we derive this scaling by modeling the ensemble of electron gyro-axes in a magnetized plasma as an overdamped spintronic condensate governed by the Landau-Lifshitz-Gilbert equation. We demonstrate that the breakdown of the "frozen-in" condition is rigorously identified as an Adler-Ohmic bifurcation: a topological phase transition where electron gyro-axes lose synchronization with the mean magnetic field. Unlike stochastic turbulence models, this framework predicts a coherent, explosive onset of resistivity that naturally saturates at the Bohm limit. We support this thesis with renormalization group theory and a novel analysis of Magnetospheric Multiscale mission data, which reveals an explosive phase space confinement consistent with collective phase slippage rather than chaotic scattering. These results suggest that Bohm resistivity is a universal topological property of magnetized matter at the critical point of reconnection.

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Magnus F Ivarsen. 2026-01-26. Magnetic reconnection as an Adler-Ohmic bifurcation: The topological origin of Bohm resistivity. https://arxiv.org/abs/2601.08054

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