Kohler's Rule Holds in the Strange Metallic Hubbard Model
Unconventional magnetotransport violating Kohler's rule has been reported in many strongly correlated strange metals, but the exact origin of these violations is yet unknown. To investigate this question, we use determinant quantum Monte Carlo to compute the magnetoresistance of the hole-doped Hubbard-Hofstadter model. Despite $T$-linear resistivity exceeding the Mott-Ioffe-Regel limit and the nominal absence of well-defined quasiparticles, we find Kohler's rule unexpectedly holds across a wide range of on-site interaction strengths and hole dopings. In particular, Kohler emerges below a crossover temperature $T^\star\approx t$ identified from the double occupancy and specific heat, coinciding with the onset of local singlet correlations between lattice sites. We thus propose that Kohler scaling in this regime reflects a more general form of many-body quantum coherence. Our results show that strong correlations and strange metallicity do not themselves generically produce anomalous magnetoresistance.