2021/10/26 by Paul Tod, Tod, Paul
Mathematics · Physics and Astronomy · #83C20 #Advanced Mathematical Theories and Applications #Differential Geometry (math.DG) #FOS: Mathematics #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #Mathematics and Applications #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.2110.13914
openalex publication_date 2021/10/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
As a footnote to arXiv:1909.07756, I show that, given a (time-like) umbilic 3-surface Σ in a 4-dimensional space-time M, the Penrose limit taken along any null geodesic Γ which lies in Σ is a diagonalisable plane-wave.