**K. BUCHNER, V. V. GOLDBERG ** and **R. ROSCA**

*Biconformal cosymplectic manifolds*

**Pages:** 41-58

**Received:** 8 July 1990

**Mathematics Subject Classification:** 53C15

**Abstract**
Let *M* be Riemannian (2*m* + 1)-dimensional *C*^{∞} -manifold endowed with a structure 2-form
Ω, a structure 1-form η and a structure vector field ξ dual to η. As a generalization of conformal
cosymplectic manifolds, *M* (Ω, η ξ g) is defined in the present paper as a "biconformal cosymplectic manifolds"
if both structure forms Ω and η are "cohomologically closed". With such a structure denoted by *B.C. Sp*(*sm* + 1, *R*) is
associated a closed 1-form w and its dual vector *W*. Different properties of the *d*^{ω}-cohomology and the Lie algebra on
*M* involving η u, Ω, *W* and ξ are discussed. If *M _{h}* is the hypersurface normal to ξ, the following salient properties are
established: (a) If