Manifolds with almost contact 3-structure and metrics of Hermitian-Norden type

Abstract

It is introduced a differentiable manifold with almost contact 3-structure which consists of an almost contact metric structure and two almost contact B-metric structures. The product of this manifold and a real line is an almost hypercomplex manifold with Hermitian-Norden metrics. It is proven that the introduced manifold of cosymplectic type is at. Some examples of the studied manifolds are given.

arXiv comment11 pages, revised, some parts are separated and further developed