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arXiv · 1510.08812

Essential conformal actions of PSL(2,R) on real-analytic compact Lorentz manifolds

Vincent Pecastaing
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Abstract

The main result of this paper is the conformal flatness of real-analytic compact Lorentz manifolds of dimension at least $3$ admitting a conformal essential (i.e. conformal, but not isometric) action of a Lie group locally isomorphic to PSL(2,R). It is established by using a general result of M. Gromov on local isometries of real-analytic $A$-rigid geometric structures. As corollary, we deduce the same conclusion for conformal essential actions of connected semi-simple Lie groups on real-analytic compact Lorentz manifolds. This work is a contribution to the understanding of the Lorentzian version of a question asked by A. Lichnerowicz.

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Vincent Pecastaing. 2015-10-29. Essential conformal actions of PSL(2,R) on real-analytic compact Lorentz manifolds. https://doi.org/10.1007/s10711-016-0212-y

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