PIRSA:15050116

Geometries of any dimension without twist and shear

APA

Podolsky, J. (2015). Geometries of any dimension without twist and shear. Perimeter Institute for Theoretical Physics. https://pirsa.org/15050116

MLA

Podolsky, Jiri. Geometries of any dimension without twist and shear. Perimeter Institute for Theoretical Physics, May. 29, 2015, https://pirsa.org/15050116

BibTex

          @misc{ scivideos_PIRSA:15050116,
            doi = {10.48660/15050116},
            url = {https://pirsa.org/15050116},
            author = {Podolsky, Jiri},
            keywords = {Strong Gravity},
            language = {en},
            title = {Geometries of any dimension without twist and shear},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2015},
            month = {may},
            note = {PIRSA:15050116 see, \url{https://scivideos.org/index.php/pirsa/15050116}}
          }
          

Jiri Podolsky Charles University

Talk numberPIRSA:15050116
Source RepositoryPIRSA
Collection

Abstract

We study a general class of D-dimensional spacetimes that admit a non-twisting and shear-free null vector field. This includes the famous non-expanding Kundt family and the expanding Robinson-Trautman family of spacetimes. In particular, we show that the algebraic structure of the Weyl tensor is I(b) or more special, and derive surprisingly simple conditions under which the optically privileged null direction is a multiple WAND. All possible algebraically special types, including the refinement to subtypes, are thus identified. No field equations are applied, so that the results are valid not only in Einstein's theory but also in its generalizations. Differences between the D=4 and D>4 cases are summarized, and we give a short discussion of some interesting particular subcases (exact gravitational waves, gyratons, non-rotating p-form black holes etc.).