发表机构
Facultad de Ciencias, Universidad Arturo Prat; Instituto de Ciencias Exactas y Naturales (ICEN), Universidad Arturo Prat; Departamento de Ciencias Exactas, Facultad de Ingeniería, Universidad San Sebastián（阿图罗·普拉特大学理学院; 阿图罗·普拉特大学精确与自然科学研究所; 圣塞巴斯蒂安大学工程学院精确科学系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究五维AdS-Chern-Simons引力中非均匀尘埃坍缩，得到精确内部解，证明壳聚焦为真实奇点，并揭示视界形成依赖于准局域质量阈值。
AI 中文摘要
我们研究了五维AdS-Chern-Simons引力中球对称、非均匀尘埃云的重力坍缩。在无挠扇区中，使用随动Lemaître-Tolman-Bondi坐标，我们推导了约化场方程，并得到了一个精确的坍缩内部解。面积半径随时间周期性演化，但物理坍缩分支仅延伸至壳聚焦或更早的正则性丧失，而初始密度决定了一个径向函数，其平方与守恒的准局域质量成正比。这区分了初始速度和密度分布控制在壳聚焦和俘获中的作用。我们推导了中心正则性和避免壳交叉的条件，分析了Kretschmann标量，并表明壳聚焦对应真实的曲率奇点，弱能量条件和强能量条件在整个正则坍缩阶段均被保持。均匀极限一致地约化为五维FLRW内部。坍缩云与静态AdS-Chern-Simons外部的黑洞分支平滑匹配。零展开表明，仅当准局域质量超过临界阈值时，才会形成有限半径的视界。高于该阈值的初始未俘获壳层在壳聚焦之前变为俘获，而低于总质量阈值时，在正则内部不会形成有限半径的未来俘获对称球面。
英文摘要
We study the gravitational collapse of a spherically symmetric, inhomogeneous dust cloud in five-dimensional AdS Chern--Simons gravity. Working in the torsion-free sector and using comoving Lema\^ıtre--Tolman--Bondi coordinates, we derive the reduced field equations and obtain an exact collapsing interior solution. The areal radius evolves periodically in time, but the physical collapsing branch extends only up to shell focusing or an earlier loss of regularity, while the initial density determines a radial function whose square is proportional to the conserved quasilocal mass. This separates the roles of the initial velocity and density profiles in controlling shell focusing and trapping. We derive conditions for central regularity and for avoiding shell crossing, analyze the Kretschmann scalar, and show that shell focusing corresponds to a genuine curvature singularity, the weak and strong energy conditions are preserved throughout the regular collapsing phase. The homogeneous limit reduces consistently to a five-dimensional FLRW interior. The collapsing cloud is matched smoothly to the black-hole branch of the static AdS Chern--Simons exterior. The null expansions show that a finite-radius apparent horizon forms only when the quasilocal mass exceeds a critical threshold. Initially untrapped shells above this threshold become trapped before shell focusing, whereas below the total-mass threshold no finite-radius future-trapped symmetry sphere forms in the regular interior.
Comments18 pages
