标题： 旋转黑洞视界之外的奇异激发 显示英文标题

标题： Singular excitement beyond the horizon of a rotating black hole

摘要： 先前的研究表明，当线性耦合到无质量标量场并被允许径向落入某些黑洞时，Unruh-DeWitt（UDW）探测器在其接近视界的过渡特性中会表现出非单调性。 具体来说，当考虑Unruh和Hartle-Hawking真空态时，自由落入(3+1)维Schwarzschild黑洞的探测器的过渡概率在视界穿越处被证明具有局部极值 [K.K. Ng 等，New J. Phys. 24 (2022) 103018]。 对于静态(2+1)维Bañados-Teitelboim-Zanelli（BTZ）黑洞，在Hartle-Hawking态下，探测器的过渡率在某些参数设置下在视界附近也被发现具有多个局部极值 [M.R. Preciado-Rivas 等，arXiv:2402.14908v1]。 这些发现具有重要意义，因为它们表明在包含量子场论效应的情况下，黑洞的事件视界可能对局部探测器是可区分的。 在本文中，我们探讨了UDW探测器自由落入旋转BTZ黑洞的问题。 我们数值计算了不同黑洞质量、黑洞角动量、探测器能级差以及无限远处场边界条件下的探测器过渡率。 我们的结果提供了一个更一般的描述，说明粒子探测器在BTZ黑洞时空中的行为，其中在角动量消失的极限情况下可以恢复之前的非旋转BTZ情况。 显示英文摘要

摘要： Previous studies have shown that an Unruh-DeWitt (UDW) detector, when coupled linearly to a massless scalar field and permitted to fall radially into certain black holes, will exhibit non-monotonicity in its transition properties near the horizon. Specifically, the transition probability of a detector freely falling into a (3+1)-dimensional Schawrzschild black hole, when considering the Unruh and Hartle-Hawking vacuum states, was shown to possess a local extremum at horizon crossing [K.K. Ng et al., New J. Phys. 24 (2022) 103018]. The transition rate of a detector falling into a static (2+1)-dimensional Ba\~nados-Teitelboim-Zanelli (BTZ) black hole, for the Hartle-Hawking state, was also found to have multiple local extrema near the horizon under certain parameter settings [M.R. Preciado-Rivas et al., arXiv:2402.14908v1]. These discoveries are of interest, as they suggest that the event horizon of a black hole may be distinguishable to a local probe when QFT effects are included. In this paper, we explore the problem of a UDW detector falling freely into a rotating BTZ black hole. We numerically compute the detector's transition rate for different values of black hole mass, black hole angular momentum, detector energy gap, and field boundary conditions at infinity. Our results lead to a more generalized description of the behaviour of particle detectors in BTZ black hole spacetime, from which the previous non-rotating BTZ case can be retrieved in the limit as angular momentum vanishes.