منابع مشابه
Affine structures on nilpotent contact Lie algebras
Any Lie algebra equipped with a symplectic form can be equipped with an affine structure. On the other hand there exist (2p + 1)-dimensional Lie algebras with contact form and no affine structure. But each nilpotent contact Lie algebra is a one-dimensional central extension of a symplectic algebra. The aim of this work is to study how we can extend, under certain conditions, the symplectic stuc...
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An almost contact metric structure is parametrized by a section σ of an associated homogeneous fibre bundle, and conditions for σ to be a harmonic section, and a harmonic map, are studied. These involve the characteristic vector field ξ, and the almost complex structure in the contact subbundle. Several examples are given where the harmonic section equations for σ reduce to those for ξ, regarde...
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We study almost contact metric structures on 5-dimensional nilpotent Lie algebras and investigate the class of left invariant almost contact metric structures on corresponding Lie groups. We determine certain classes that a five-dimensional nilpotent Lie group can not be equipped with.
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We show that an oriented elliptic 3-manifold admits a universally tight positive contact structure if and only if the corresponding group of deck transformations on S3 (after possibly conjugating by an isometry) preserves the standard contact structure. We also relate universally tight contact structures on 3-manifolds covered by S3 to the isomorphism SO(4) = (SU(2) × SU(2))/±1. The main tool u...
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ژورنال
عنوان ژورنال: Kodai Mathematical Journal
سال: 1973
ISSN: 0386-5991
DOI: 10.2996/kmj/1138846766