Chaos bound for spinning particles in Kerr-Newman-AdS black holes

A bstract In this paper, we investigate the chaos bound violation of spinning charged test particles in the Kerr-Newman-AdS spacetime by comparing the Lyapunov exponent of unstable circular orbits with the black hole surface gravity. We find that the violation is governed by the relative balance between the local orbital-instability and surface gravity scales, while spacetime rotation, charge, AdS curvature, and particle spin modify this balance in different ways. In rotating backgrounds, the violation depends strongly on the relative orientation between the particle total angular momentum and the black hole rotation, with anti-aligned configurations generally favoring violation. Particle spin further shifts the violation boundary through spin-curvature coupling, although its influence remains comparatively weak over the spin range considered. The cosmological constant has a background-dependent influence. These results show that the parameter dependence of chaos bound violation reflects the competition between the local orbital-instability and surface gravity scales.