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Automorphisms of Real 4 Dimensional Lie Algebras and the Invariant Characterization of Homogeneous 4-Spaces

T. Christodoulakis·G. O. Papadopoulos·A. Dimakis
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Abstract

The automorphisms of all 4-dimensional, real Lie Algebras are presented in a comprehensive way. Their action on the space of $4\times 4$, real, symmetric and positive definite, matrices, defines equivalence classes which are used for the invariant characterization of the 4-dimensional homogeneous spaces which possess an invariant basis.

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T. Christodoulakis, G. O. Papadopoulos, A. Dimakis. 2002-11-13. Automorphisms of Real 4 Dimensional Lie Algebras and the Invariant Characterization of Homogeneous 4-Spaces. https://doi.org/10.1088/0305-4470%2F36%2F2%2F310

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