Chaos Bound and Circular Motion Around Bardeen Black Holes

In this paper, we study the influence of particle’s charge and angular momentum around charged Bardeen black holes on the Lyapunov exponent, and find the spatial regions where the chaos bound is violated for certain values of the black holes’ parameters. The exponent is obtained by calculating the eigenvalues of the Jacobian matrix in the phase space. The result shows the bound is violated in the near-horizon regions and at a certain distance from the horizons. When the charge or angular momentum of a particle is fixed at at certain values, the spatial regions decreases with the increase of the black hole charge, while when the black holes’ charge is fixed, it decreases with the increase of the particle’s charge or angular momentum.