A singularity theorem based on spatial averages
Abstract
Description
Inspired by Raychaudhuri's work, and using the equation named after him as a basic ingredient, a new singularity theorem is proved. Open non-rotating everywhere expanding universes with non-vanishing spatial average of the matter variables are severely geodesically incomplete to the past. Another way of stating the result is that, under the same conditions, any singularity-free model must have a vanishing spatial average of the energy density (and other physical variables). This is very satisfactory and provides a clear decisive difference between singular and non-singular cosmologies.
Corrections made in the main theorem and related places. 16 pages, no figures. Invited contribution to the Pramana special issue, dedicated to A K Raychaudhuri, on "the Raychaudhuri Equation and its Role in Modern Cosmology" (Edited by Naresh Dadhich, Pankaj Joshi and Probir Roy). Final version to be published
Corrections made in the main theorem and related places. 16 pages, no figures. Invited contribution to the Pramana special issue, dedicated to A K Raychaudhuri, on "the Raychaudhuri Equation and its Role in Modern Cosmology" (Edited by Naresh Dadhich, Pankaj Joshi and Probir Roy). Final version to be published