Publikace ÚTF

Averaging problem in GR and cosmology is of fundamental importance.
It is still not clear how to unambiguously average Einstein equations and the metric
tensor. One of the most promising attempts how to deal with averaging in GR are
the Buchert equations. However, only scalar part of the Einstein equations is averaged
and the system is not closed. Here we will present LRS (locally rotationally
symmetric) spacetimes, where one can find preferred spatial direction and the evolution
and the constraint equations are described only by scalars. By averaging these
scalars we will obtain generalized Buchert equations (for LRS spacetimes).