Witten, E. (2020) Light Rays, Singularities, and All That. Reviews of Modern Physics, 92, Article ID: 045004.
https://doi.org/10.1103/RevModPhys.92.045004

has been cited by the following article:

• TITLE: Null Geodesics, Raychaudhuri Equation, Trapped Surfaces, and Penrose Singularity Theorem

  AUTHORS: Miguel Socolovsky

  KEYWORDS: Null Geodesics, Trapped Surfaces, Singularity Theorem

  JOURNAL NAME: Journal of High Energy Physics, Gravitation and Cosmology, Vol.8 No.3, June 29, 2022

  ABSTRACT: We review the concept of congruence of null geodesics, the Raychaudhuri equation for the expansion, its harmonic oscillator version and associated “quantum” propagator, the role of the equation in the derivation of the Penrose singularity theorem, the definition of trapped surfaces, and the derivation of the theorem itself.