报告题目: Superradiant instabilities of massive bosons around exotic compact objects

报告人：麦展风博士后（北京大学）

主持人：李鹏程  副教授

报告时间：2023年11月3日（星期五）上午10:00

报告地点：物理楼（18号楼）二楼213室学术报告厅

欢迎广大师生参加!

                                     物理与光电学院

                                     2023年10月23日

摘要：Superradiantly unstable ultralight particles around a classical rotating black hole (BH) can form an exponentially growing bosonic cloud, which have been shown to provide an astrophysical probe to detect ultralight particles and constrain their mass. However, the classical BH picture has been questioned, and different theoretical alternatives have been proposed. Exotic compact objects (ECOs) are horizonless alternatives to BHs featuring a reflective surface (with a reflectivity K) in place of the event horizon. In this talk, I will talk about the superradiant instabilities around ECOs, particularly focusing on the influence of the boundary reflection. The calculation for the growth rate of superradiant instabilities around ECOs shows that the result can be related to the BH case by a correction factor with fruitful physical significance. Additionally, I shall talk about the time evolution of superradiant instabilities and find that the boundary reflection can either shorten or prolong the growth timescale. As a result, the boundary reflection alters the superradiance exclusion region on the Regge plane, potentially affecting constraints on the mass of ultralight particles. For a mildly reflective surface, the exclusion region is not substantially changed, while significant effects from the boundary reflection can occur for an extreme reflectivity.

报告人简介：麦展风，北京大学科维理天文与天体物理研究所助理研究员/博士后。2015年本科毕业于华南师范大学物理学勷勤创新班；2018年硕士毕业于北京师范大学；2022年博士毕业于天津大学。主要研究兴趣是黑洞物理及在引力波中的应用，特别是黑洞准正则模与超辐射不稳定性在引力波中的应用。在Physical Review D, Science China Physics, Mechanics & Astronomy, European Physical Journal C, Physics Letter B, Journal of High Energy Physics 发表文章13篇，其中第一作者6篇，通讯作者2篇。目前主持国家自然科学基金委理论物理专项基金1项。