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Inhomogeneous Cosmological Models Containing Homogeneous Inner Hypersurface Geometry. Changes of the Bianchi Type

H. -J. Schmidt
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Abstract

There are investigated such cosmological models which instead of the usual spatial homogeneity property only fulfil the condition that in a certain synchronized system of reference all spacelike sections t = const. are homogeneous manifolds. This allows time-dependent changes of the BIANCHI type. Discussing differential geometrical theorems it is shown which of them are permitted. Besides the trivial case of changing into type I there exist some possible changes between other types. However, physical reasons like energy inequalities partially exclude them.

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H. -J. Schmidt. 2001-05-28. Inhomogeneous Cosmological Models Containing Homogeneous Inner Hypersurface Geometry. Changes of the Bianchi Type. https://doi.org/10.1002/asna.2103030403

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