“无毛”定理不适用于旋转中子星坍缩形成的黑洞。旋转的中子星可以通过真空击穿自我产生粒子，形成一个高传导的等离子体磁层，这样磁场线在坍缩之前和坍缩期间都有效地“冻结”在恒星中。在没有电阻率的限制下，这引入了拓扑约束，其禁止磁场滑出新形成的事件视界。因此，在中子星坍缩成黑洞的过程中，黑洞保持磁通管的数量N_B = e Φ_ \infty /（πc \hbar），其中Φ_ \infty是通过母星半球并向外无穷远的初始磁通量。黑洞的磁层随后弛豫到分裂的磁层磁场几何形状，并在事件视界外产生自生电流。由此产生的赤道电流片的耗散导致锚定的通量管的缓慢损失，这一过程使黑洞在长的电阻时间尺度上变秃，而不是真空“无毛”定理所预期的短的光交叉时间尺度。
英文摘要：
The "no hair" theorem is not applicable to black holes formed from collapse of a rotating neutron star. Rotating neutron stars can self-produce particles via vacuum breakdown forming a highly conducting plasma magnetosphere such that magnetic field lines are effectively "frozen-in" the star both before and during collapse. In the limit of no resistivity, this introduces a topological constraint which prohibits the magnetic field from sliding off the newly-formed event horizon. As a result, during collapse of a neutron star into a black hole, the latter conserves the number of magnetic flux tubes N_B = e Φ_\infty /(πc \hbar), where Φ_\infty is the initial magnetic flux through the hemispheres of the progenitor and out to infinity. The black hole's magnetosphere subsequently relaxes to the split monopole magnetic field geometry with self-generated currents outside the event horizon. The dissipation of the resulting equatorial current sheet leads to a slow loss of the anchored flux tubes, a process that balds the black hole on long resistive time scales rather than the short light-crossing time scales expected from the vacuum "no-hair" theorem.
Probing the Scalar Hair of Rotating Horndeski Black Holes through Thick Disk Images
School of Physics and Optoelectronics, South China University of Technology（华南理工大学物理与光电学院）；Tsung-Dao Lee Institute, Shanghai Jiao-Tong University（上海交通大学李政道研究所）；School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院）；Key Laboratory of Multiscale Spin Physics (Ministry of Education), Beijing Normal University（北京师范大学多尺度自旋物理教育部重点实验室）
