Semi-invariant product of a certain class of almost contact manifolds

Semi-invariant warped product submanifolds of almost contact manifolds

* Correspondence: meraj79@gmail. com Department of Mathematics, University of Tabuk, Tabuk, Kingdom of Saudi Arabia Full list of author information is available at the end of the article Abstract In this article, we have obtained necessary and sufficient conditions in terms of canonical structure F on a semi-invariant submanifold of an almost contact manifold under which the submanifold reduced...

Warped Product Semi-Invariant Submanifolds in Almost Paracontact Riemannian Manifolds

We show that there exist no proper warped product semi-invariant submanifolds in almost paracontact Riemannian manifolds such that totally geodesic submanifold and totally umbilical submanifold of the warped product are invariant and anti-invariant, respectively. Therefore, we consider warped product semi-invariant submanifolds in the form N N⊥×fNT by reversing two factor manifolds NT and N⊥. W...

Realization of a Certain Class of Semi-Groups as Value Semi-Groups of Valuations

Semi-slant Pseudo-riemannian Submersions from Indefinite Almost Contact 3-structure Manifolds onto Pseudo-riemannian Manifolds

In this paper, we introduce the notion of a semi-slant pseudoRiemannian submersion from an indefinite almost contact 3-structure manifold onto a pseudo-Riemannian manifold. We investigate the geometry of foliations determined by horizontal and vertical distributions and provide a non-trivial example. We also find a necessary and sufficient condition for a semi-slant submersion to be totally geo...

Almost invariant manifolds for divergence-free fields

It is shown that toroidal surfaces that extremize a properly weighted surface integral of the squared normal component of a solenoidal three-vector field capture the local invariant dynamics, in that a field line that is anywhere tangential to the surface must be confined to the surface everywhere. In addition to an elementary three-vector calculus derivation, which relies on a curvilinear toro...