2017/04/19 by Shaoqi Hou, Hou, Shaoqi
Physics and Astronomy · #Advanced Differential Geometry Research #Astrophysical Phenomena and Observations #Black Holes and Theoretical Physics #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Theory (hep-th) #Mathematical Physics (math-ph)
paper · pdf · doi:10.48550/arxiv.1704.05701
openalex publication_date 2017/04/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The common intrinsic geometry shared by all the null hypersurfaces gives rise to the asymptotic symmetries found on the null infinities \mathscr I^± and the isolated horizons Δ. In this work, the properties of a null hypersurface are reviewed and the invariance of its intrinsic geometry (nanbhab) is revealed under the spacetime conformal transformation. The generators, i.e., infinitesimal symmetries, of the conformal transformation tangent to the null hypersurface are defined and classified by their effects on the induced metric and the normal vector field. Two particular examples and their symmetries are discussed, that is, the null infinities \mathscr I^± of an asymptotic flat spacetime, and the isolated horizon Δ of a black hole.