活动名称：Self-interactingsuperradiantBose-Einstein condensates around Kerr black holes

时间：2026年9月24日（星期二）时间点14:00

地点：集贤楼511

主讲人：郭森

主办单位：重庆师范大学物理与光电工程学院

主讲人简介：郭森，重庆师范大学物理与光电工程学院副教授，近年来一直围绕黑洞成像与强引力场粒子辐射的理论与数值研究，主要聚焦“黑洞成像”方向。研究兴趣包括：黑洞物理，广义相对论数值模拟，超材料模拟。近五年，发表SCI论文33篇，其中第一作者和通讯作者25篇，H指数16。代表性工作获2023年中国高被引论文奖，ESI高被引论文奖。担任PRD，PLB，APJ，CQG等天文、物理期刊审稿人。

活动简介：Ultralight bosonic dark matter can formsuperradiantclouds around rotating black holes. While scalar self-interactions are typically studied on static backgrounds, we treat them directly on the Kerr metric. By applying a single-mode projection to the quartic Klein–Gordon equation, we derive a one-dimensional Gross–Pitaevskiiequation where the effective coupling is geometrically modulated by the horizon function. Solving this system at a fixed particle number reduces the solution family to a single dimensionless parameter. We find that rotation reshapes the condensate from a spherical shell into an equatorial torus with identically vanishing density on the rotation axis. This structure deviates appreciably from the linear regime only for . Crucially, self-repulsion quenches superradiance only within a narrow frequency window of relative width . Because this window is about one percent, self-interaction alone cannot saturate the instability, meaning the black hole must spin down instead. Throughout this nonlinear regime, the exact quantization relationreceives no correction. For ahost at, this spin-down process results in a macroscopic toroidal cloud emitting gravitational waves near 650 Hz.