49 citations · 113 across the 27 of their papers we have counts for
22 papers · 1 filter
The Obata first eigenvalue theorems on a seven dimensional quaternionic contact manifold
Abdelrahman Mohamed, Dimiter Vassilev
We show that a compact quaternionic contact manifold of dimension seven that satisfies a Lichnerowicz-type lower Ricci-type bound and has the -function of any eigenfunction of t…
Non-umbilical quaternionic contact hypersurfaces in hyper-Kähler manifolds
Stefan Ivanov, Ivan Minchev, Dimiter Vassilev
We show that any compact quaternionic contact (qc) hypersurfaces in a hyper-Kähler manifold which is not totally umbilical has an induced qc structure, locally qc homothetic to the…
The monotonicity of an entropy like energy for the heat equation on a quaternionic contact and CR manifolds
Dimiter Vassilev
A proof of the monotonicity of an entropy like energy for the heat equation on a quaternionic contact and CR manifolds is proven
The Lichnerowicz and Obata first eigenvalue theorems and the Obata uniqueness result in the Yamabe problem on CR and quaternionic contact manifolds
Stefan Ivanov, Dimiter Vassilev
We report on some aspects and recent progress in certain problems in the sub-Riemannian CR and quaternionic contact (QC) geometries. The focus are the corresponding Yamabe problems…
Solution of the qc Yamabe equation on a 3-Sasakian manifold and the quaternionic Heisenberg group
Stefan Ivanov, Ivan Minchev, Dimiter Vassilev
A complete solution to the quaternionic contact Yamabe equation on the qc sphere of dimension as well as on the quaternionic Heisenberg group is given. A uniqueness theorem…
The quaternionic Heisenberg group and Heterotic String Solutions with non-constant dilaton in dimensions 7 and 5
Marisa Fernandez, Stefan Ivanov, Luis Ugarte +1
New smooth solutions of the Strominger system with non vanishing flux, non-trivial instanton and non-constant dilaton based on the quaternionic Heisenberg group are constructed. We…