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arXiv · 0707.3773

Conformal paracontact curvature and the local flatness theorem

Stefan Ivanov·Dimiter Vassilev·Simeon Zamkovoy
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Abstract

A curvature-type tensor invariant called para contact (pc) conformal curvature is defined on a paracontact manifold. It is shown that a paracontact manifold is locally paracontact conformal to the hyperbolic Heisenberg group or to a hyperquadric of neutral signature if and only if the pc conformal curvature vanishes. In the three dimensional case the corresponding result is achieved through employing a certain symmetric (0,2) tensor. The well known result of Cartan-Chern-Moser giving necessary and sufficient condition a CR-structure to be CR equivalent to a hyperquadric in the complex vector space is presented in-line with the paracontact case. An explicit formula for the regular part of a solution to the sub-ultrahyperbolic Yamabe equation on the hyperbolic Heisenberg group is shown.

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Stefan Ivanov, Dimiter Vassilev, Simeon Zamkovoy. 2008-12-08. Conformal paracontact curvature and the local flatness theorem. https://arxiv.org/abs/0707.3773

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