标题： 带电粒子在Kerr-Sen-AdS黑洞中的Lyapunov指数界限 显示英文标题

标题： Bound on Lyapunov exponent for a charged particle in Kerr-Sen-AdS Black Hole

摘要： 我们研究了带电粒子在Gibbons–Maeda–Garfinkle–Horowitz–Strominger（GMGHS）–AdS和Kerr–Sen–AdS黑洞背景下的Lyapunov指数的上界，这些背景来源于异弦理论和规范超引力的低能有效作用。 我们在不稳定轨道附近分析Lyapunov指数以检查可能的界限违反。 我们的结果显示该界限对电荷的符号和大小、粒子角动量、黑洞自旋以及负宇宙学常数非常敏感。 在极端或接近极端情况下，这种违反现象尤为显著。 数值分析支持了分析预测，并突显了弦启发的黑洞与带电粒子之间的相互作用。 显示英文摘要

摘要： We investigate the upper bound of the Lyapunov exponent for a charged particle in the Gibbons--Maeda--Garfinkle--Horowitz--Strominger (GMGHS)--AdS and Kerr--Sen--AdS black hole backgrounds, which originate from the low-energy effective actions of heterotic string theory and gauged supergravity. We analyze the Lyapunov exponent near the unstable orbit to examine possible violations of the bound. Our results indicate that the bound is sensitive to the signs and magnitudes of the charges, the angular momentum of the particle, the black hole spin, and the negative cosmological constant. The violations are pronounced in the extremal or near-extremal regime. Numerical analysis supports the analytical predictions and highlights the interplay between the string-inspired black hole and the charged particle.