5 papers
Cayley 4-frames and a quaternion-Kähler reduction related to Spin(7)
Liviu Ornea, Paolo Piccinni
We describe an action of on that allows to obtain a -quotient of CAYLEY (the Grassmannian of oriented 4-planes in closed under the three-fold c…
Complex Structures on some Stiefel Manifolds
Liviu Ornea, Paolo Piccinni
We discuss conditions for the integrability of an almost complex structure defined on the total space of an induced Hopf S^3-bundle over a Sasakian manifold . As an application, we…
3-Sasakian Geometry, Nilpotent Orbits, and Exceptional Quotients
Charles P. Boyer, Krzysztof Galicki, Paolo Piccinni
Using 3-Sasakian reduction techniques we obtain infinite families of new 3-Sasakian manifolds and in…
Foliations with Transversal Quaternionic Structures
Paolo Piccinni, Izu Vaisman
We consider manifolds equipped with a foliation of codimension , and an almost quaternionic structure on the transversal bundle of . After discussing con…
On some Moment Maps and Induced Hopf Bundles in the Quaternionic Projective Space
Liviu Ornea, Paolo Piccinni
We describe a diagram containing the zero sets of the moment maps associated to the diagonal U(1) and Sp(1) actions on the quaternionic projective space HP^n. These sets are relate…