Results 11 to 20 of about 308 (43)
The even Clifford structure of the fourth Severi variety
Complex Manifolds, 2015 TheHermitian symmetric spaceM = EIII appears in the classification of complete simply connected Riemannian manifolds carrying a parallel even Clifford structure [19].
Parton Maurizio, Piccinni Paolo
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Holonomy groups of pseudo-quaternionic-K\"ahlerian manifolds of non-zero scalar curvature
, 2010 The holonomy group $G$ of a pseudo-quaternionic-K\"ahlerian manifold of signature $(4r,4s)$ with non-zero scalar curvature is contained in $\Sp(1)\cdot\Sp(r,s)$ and it contains $\Sp(1)$.
A. Swann +6 more
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Hyperk\"ahler Manifolds of Curves in Twistor Spaces [PDF]
, 2014 We discuss hypercomplex and hyperk\"ahler structures obtained from higher degree curves in complex spaces fibring over ${\mathbb{P}}^1$.Comment: v4: added the missing assumption on dimension in Theorem 3 ...
Bielawski, Roger
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Spin(9) geometry of the octonionic Hopf fibration [PDF]
, 2013 We deal with Riemannian properties of the octonionic Hopf fibration S^{15}-->S^8, in terms of the structure given by its symmetry group Spin(9). In particular, we show that any vertical vector field has at least one zero, thus reproving the non-existence
Ornea, Liviu +3 more
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The second Betti number of hyperk\"ahler manifolds [PDF]
, 2015 Let $M$ be a compact irreducible hyperkahler manifold, from Bogomolov inequality [V1] we obtain forbidden values of the second Betti number $b_2$ in arbitrary dimension.
Kurnosov, Nikon
core
Parallelizations on products of spheres and octonionic geometry
Complex Manifolds, 2019 A classical theoremof Kervaire states that products of spheres are parallelizable if and only if at least one of the factors has odd dimension. Two explicit parallelizations on Sm × S2h−1 seem to be quite natural, and have been previously studied by the ...
Parton Maurizio, Piccinni Paolo
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A Nearly Quaternionic Structure on SU(3)
, 2009 It is shown that the compact Lie group SU(3) admits an Sp(2)Sp(1)-structure whose distinguished 2-forms $\omega_1,\omega_2,\omega_3$ span a differential ideal. This is achieved by first reducing the structure further to a subgroup isomorphic to SO(3)
Besse +15 more
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Abelian simply transitive affine groups of symplectic type [PDF]
, 2001 We construct a model space $C(\gsp(\bR^{2n}))$ for the variety of Abelian simply transitive groups of affine transformations of type ${\rm Sp}(\bR^{2n})$.
Baues, Oliver, Cortes, Vicente
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Collections of parabolic orbits in homogeneous spaces, homogeneous dynamics and hyperkahler geometry
, 2016 Let $M$ be a hyperk\"ahler manifold with $b_2(M)\geq 5$. We improve our earlier results on the Morrison-Kawamata cone conjecture by showing that the Beauville-Bogomolov square of the primitive MBM classes (i.e.
Amerik, Ekaterina, Verbitsky, Misha
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On the cohomology of some exceptional symmetric spaces
, 2016 This is a survey on the construction of a canonical or "octonionic K\"ahler" 8-form, representing one of the generators of the cohomology of the four Cayley-Rosenfeld projective planes.
A. Borel +20 more
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