黑洞的指纹——阴影及其简并性
The Fingerprints of Black Holes - Shadows and their Degeneracies
AI总结：
本文证明单位质量 Kerr-Newman 黑洞阴影在远离对称轴处无连续简并，可据此反演黑洞与观测者参数；但 Kerr-Newman-Taub-NUT 情形存在连续参数简并。
摘要：
我们证明，在远离对称轴的位置，单位质量的任意 Kerr-Newman 黑洞时空外部区域中，任意一点观测者所看到的阴影之间不存在连续简并。因此，除可能的离散变化外，观测者可通过测量黑洞阴影，确定所观测黑洞的角动量和电荷，以及观测者自身的径向位置和相对于赤道平面的仰角。此外，其相对于标准观测者的相对速度也可被测量。另一方面，在 Kerr-Newman-Taub-NUT 黑洞情形中，黑洞阴影无法实现全部参数的分辨，因为此情形中存在一个联系特定角动量、电荷、NUT 荷与仰角的连续简并。
英文摘要：
We show that, away from the axis of symmetry, no continuous degeneration exists between the shadows of observers at any point in the exterior region of any Kerr-Newman black hole spacetime of unit mass. Therefore, except possibly for discrete changes, an observer can, by measuring the black holes shadow, determine the angular momentum and the charge of the black hole under observation, as well as the observer's radial position and angle of elevation above the equatorial plane. Furthermore, his/her relative velocity compared to a standard observer can also be measured. On the other hand, the black hole shadow does not allow for a full parameter resolution in the case of a Kerr-Newman-Taub-NUT black hole, as a continuous degeneration relating specific angular momentum, electric charge, NUT charge and elevation angle exists in this case.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
