12 citations · 29 across the 12 of their papers we have counts for
13 papers
Four-dimensional almost-Einstein manifolds with circulant structures
Iva Dokuzova, Georgi Dzhelepov, Dimitar Razpopov
This paper considers a four-dimensional Riemannian manifold with an additional circulant tensor structure . We prove that such a manifold is almost-Einstein if the curvature ten…
Spheres and circles with respect to an indefinite metric on a Riemanian manifold with a skew-circulant structure
Georgi Dzhelepov, Iva Dokuzova, Dimitar Razpopov
We study hyper-spheres, spheres and circles, with respect to an indefinite metric, in a tangent space on a 4-dimensional differentiable manifold. The manifold is equipped with a po…
A Riemannian manifold with skew-circulant structures and an associated locally conformal Kähler manifold
Dimitar Razpopov, Iva Dokuzova
A 4-dimensional Riemannian manifold M, equipped with an additional tensor structure S, whose fourth power is minus identity, is considered. The structure S has a skew-circulant mat…
The value of the work done by an isotropic vector force field along an isotropic curve
Dimitar Razpopov, Georgi Dzhelepov
In the present paper we consider a 3-dimensional differentiable manifold equipped with a Riemannian metric and an endomorphism , whose third power is the identity and $Q…
Two types of Lie Groups as 4-dimensional Riemannian manifolds with circulant structure
Iva Dokuzova, Dimitar Razpopov, Mancho Manev
A 4-dimensional Riemannian manifold equipped with an endomorphism of the tangent bundle, whose fourth power is the identity, is considered. The matrix of this structure in some bas…
Riemannian almost product manifolds generated by a circulant structure
Dobrinka Gribacheva, Dimitar Razpopov
A 4-dimensional Riemannian manifold equipped with a circulant structure, which is an isometry with respect to the metric and its fourth power is the identity, is considered. The al…