306 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Universidade do PortoPT174 papers
- University of CoimbraPT98 papers
- University of MinhoPT81 papers
- University of LisbonPT24 papers
- Centre National de la Recherche ScientifiqueFR22 papers
- Instituto Superior TécnicoPT22 papers
- UCLouvainBE13 papers
- Universidade Federal da BahiaBR13 papers
- Centro de Análise Matemática Geometria e Sistemas DinâmicosPT10 papers
- Pontifícia Universidade Católica do Rio de JaneiroBR10 papers
- Universidad de La LagunaES9 papers
- Universidade Federal do Rio de JaneiroBR9 papers
31 papers · 1 filter
Non-connected Lie groups, twisted equivariant bundles and coverings
G. Barajas, O. García-Prada, P. B. Gothen +1
Let be a finite group acting on a Lie group . We consider a class of group extensions defined by this action and a -cocycle of with v…
Curvature-adapted submanifolds of semi-Riemannian groups
Margarida Camarinha, Matteo Raffaelli
We study semi-Riemannian submanifolds of arbitrary codimension in a Lie group equipped with a bi-invariant metric. In particular, we show that, if the normal bundle of $M \subs…
Split Courant algebroids as -structures
Paulo Antunes, Joana M. Nunes da Costa
We show that split Courant algebroids, i.e., those defined on a Whitney sum , are in a one-to-one correspondence with multiplicative curved -algebras. This…
Nearly Sasakian manifolds revisited
Beniamino Cappelletti-Montano, Antonio De Nicola, Giulia Dileo +1
We provide a new, self-contained and more conceptual proof of the result that an almost contact metric manifold of dimension greater than 5 is Sasakian if and only if it is nearly…
The universal Lie -algebroid of a singular foliation
Camille Laurent-Gengoux, Sylvain Lavau, Thomas Strobl
We associate a Lie -algebroid to every resolution of a singular foliation, where we consider a singular foliation as a locally generated -submodule of vector f…
Almost formality of quasi-Sasakian and Vaisman manifolds with applications to nilmanifolds
Beniamino Cappelletti-Montano, Antonio De Nicola, Juan Carlos Marrero +1
We provide models that are as close as possible to being formal for a large class of compact manifolds that admit a transversely Kaehler structure, including Vaisman and quasi-Sasa…
Orbispaces as differentiable stratified spaces
Marius Crainic, João Nuno Mestre
We present some features of the smooth structure, and of the canonical stratification on the orbit space of a proper Lie groupoid. One of the main features is that of Morita invari…
Maximal Higgs bundles for adjoint forms via Cayley correspondence
Oscar García-Prada, André Oliveira
For a fixed compact Riemann surface X, of genus at least 2, we count the number of connected components of the moduli space of maximal Higgs bundles over X for the hermitian groups…
The modular class of a Dirac map
Raquel Caseiro
In this paper we study the modular classes of Dirac manifolds and of Dirac maps, and we discuss their basic properties. We apply these results to explain the relationship between t…
Hard Lefschetz Theorem for Vaisman manifolds
Beniamino Cappelletti-Montano, Antonio De Nicola, Juan Carlos Marrero +1
We establish a Hard Lefschetz Theorem for the de Rham cohomology of compact Vaisman manifolds. A similar result is proved for the basic cohomology with respect to the Lee vector fi…
Dirichlet principal eigenvalue comparison theorems in geometry with torsion
Ana Cristina Ferreira, Isabel Salavessa
We describe min-max formulas for the principal eigenvalue of a -drift Laplacian defined by a vector field on a geodesic ball of a Riemannian manifold . Then we derive com…
A non-Sasakian Lefschetz K-contact manifold of Tievsky type
Beniamino Cappelletti-Montano, Antonio De Nicola, Juan Carlos Marrero +1
We find a family of five dimensional completely solvable compact manifolds that constitute the first examples of -contact manifolds which satisfy the Hard Lefschetz Theorem and…
Quaternionic Heisenberg groups as naturally reductive homogeneous spaces
Ilka Agricola, Ana Cristina Ferreira, Reinier Storm
In this note, we describe the geometry of the quaternionic Heisenberg groups from a Riemannian viewpoint. We show, in all dimensions, that they carry an almost -contact metric s…
Generalized Goldberg Formula
Antonio De Nicola, Ivan Yudin
In this paper we prove a useful formula for the graded commutator of the Hodge codifferential with the left wedge multiplication by a fixed -form acting on the de Rham algebra o…
Hypersymplectic structures with torsion on Lie algebroids
P. Antunes, J. M. Nunes da Costa
Hypersymplectic structures with torsion on Lie algebroids are investigated. We show that each hypersymplectic structure with torsion on a Lie algebroid determines three Nijenhuis m…
Covariant Lie derivatives and Frölicher-Nijenhuis bracket on Lie Algebroids
Antonio De Nicola, Ivan Yudin
We define covariant Lie derivatives acting on vector-valued forms on Lie algebroids and study their properties. This allows us to obtain a concise formula for the Frölicher-Nijenhu…
Cosymplectic p-spheres
Beniamino Cappelletti-Montano, Antonio De Nicola, Ivan Yudin
We introduce cosymplectic circles and cosymplectic spheres, which are the analogues in the cosymplectic setting of contact circles and contact spheres. We provide a complete classi…
Sasakian nilmanifolds
Beniamino Cappelletti-Montano, Antonio De Nicola, Juan Carlos Marrero +1
We prove that a compact nilmanifold admits a Sasakian structure if and only if it is a compact quotient of the generalized Heisenberg group of odd dimension by a co-compact discret…
Examples of compact K-contact manifolds with no Sasakian metric
Beniamino Cappelletti-Montano, Antonio De Nicola, Juan Carlos Marrero +1
Using the Hard Lefschetz Theorem for Sasakian manifolds, we find two examples of compact K-contact nilmanifolds with no compatible Sasakian metric in dimensions five and seven, res…
A survey on cosymplectic geometry
Beniamino Cappelletti-Montano, Antonio De Nicola, Ivan Yudin
We give an up-to-date overview of geometric and topological properties of cosymplectic and coKaehler manifolds. We also mention some of their applications to time-dependent mechani…
Curvature properties of 3-quasi-Sasakian manifolds
Beniamino Cappelletti Montano, Antonio De Nicola, Ivan Yudin
We find some curvature properties of 3-quasi-Sasakian manifolds which are similar to some well-known identities holding in the Sasakian case. As an application, we prove that any 3…
Hom-Lie algebroids
Camille Laurent-Gengoux, Joana Teles
We define hom-Lie algebroids, a definition that may seem cumbersome at first, but which is justified, first, by a one-to-one corespondence with hom-Gerstenhaber algebras, a notion…
Einstein manifolds with skew torsion
Ilka Agricola, Ana Cristina Ferreira
This paper is devoted to the first systematic investigation of manifolds that are Einstein for a connection with skew symmetric torsion. We derive the Einstein equation from a vari…
Nijenhuis and Compatible Tensors on Lie and Courant algebroids
Paulo Antunes, Joana M. Nunes da Costa
We show that well known structures on Lie algebroids can be viewed as Nijenhuis tensors or pairs of compatible tensors on Courant algebroids. We study compatibility and construct h…