Universal spacetimes in four dimensions
Journal article, Peer reviewed
Published version
Permanent lenke
http://hdl.handle.net/11250/2493340Utgivelsesdato
2017-10Metadata
Vis full innførselSamlinger
Originalversjon
Hervik, S., Pravda, V., Pravdova, A. (2017) Universal spacetimes in four dimensions. Journal of High Energy Physics, 2017(28) 10.1007/JHEP10(2017)028Sammendrag
Universal spacetimes are exact solutions to all higher-order theories of gravity. We study these spacetimes in four dimensions and provide necessary and sufficient conditions for universality for all Petrov types except of type II. We show that all universal spacetimes in four dimensions are algebraically special and Kundt. Petrov type D universal spacetimes are necessarily direct products of two 2-spaces of constant and equal curvature. Furthermore, type II universal spacetimes necessarily possess a null recurrent direction and they admit the above type D direct product metrics as a limit. Such spacetimes represent gravitational waves propagating on these backgrounds. Type III universal spacetimes are also investigated. We determine necessary and sufficient conditions for universality and present an explicit example of a type III universal Kundt non-recurrent metric.