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arXiv · 2609.04814

Spin-Charge Subordination in the Infinite-$U$ $SU(N)$ Hubbard Chain

Abstract

We obtain the exact full counting statistics of charge and flavor transport in the one-dimensional infinite-$U$ $SU(N)$ Hubbard model. The no-passing constraint freezes the ordered flavor sequence while the particle coordinates evolve as free spinless fermions. Consequently, charge transfer is governed by a free-fermion determinant, whereas flavor transfer is exactly subordinated to the number of particles crossing the observation cut. For an arbitrary traceless Cartan generator this yields an exact relation between the charge and flavor cumulants. The complete asymptotic flavor distribution is a universal non-Gaussian M-Wright law. Together, these results establish spin--charge subordination as a kinematic mechanism for anomalously slow internal-state transport in one-dimensional impenetrable quantum gases.

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Cătălin Paşcu Moca, Ovidiu I. Pâţu, Gergely Zaránd, Balázs Dóra. 2026-09-04. Spin-Charge Subordination in the Infinite-$U$ $SU(N)$ Hubbard Chain. https://arxiv.org/abs/2609.04814

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