Averaging in LRS class II spacetimes

  • Petr Kašpar
  • Otakar Svítek
Research Article


We generalize Buchert’s averaged equations (Gen Relativ Gravit 32; 105, 2000; Gen Relativ Gravit 33; 1381, 2001) to LRS class II dust model in the sense that all Einstein equations are averaged, not only the trace part. We derive the relevant averaged equations and we investigate backreaction on expansion and shear scalars in an approximate LTB model. Finally we propose a way to close the system of averaged equations.


LRS family Cosmology Averaging 



We would like to thank R. Sussman for a useful discussion. We would also like to express our gratitude to the referee for correcting and improving our paper. P.K. was supported by Grants GAUK 398911 and SVV-267301. O.S. acknowledges the support of Grant GAČR 14-37086G.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Faculty of Mathematics and Physics, Institute of Theoretical PhysicsCharles University in PraguePrague 8Czech Republic

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