Rigidity of irreducible Hermitian symmetric spaces of the compact type under Kähler deformation

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Projective manifolds dominated by abelian varieties

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Uniruled projective manifolds with irreducible reductive G-structures

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Mapping of LPS-Binding Site on Human Leukocyte Integrin Beta-2 Subunit

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Deformation rigidity of the rational homogeneous space associated to a long simple root

As a continuation of our previous works we study the conjecture on the rigidity under Kähler deformation of the complex structure of rational homogeneous spaces G / P of Picard number 1, confirming its validity whenever G / P is associated to a long simple root. For these rational homogeneous spaces the minimal G-invariant holomorphic distribution D is spanned by varieties of minimal rational tangents, and, excepting the symmetric and the contact cases, the complex structure of G / P is completely determined by the nilpotent symbol algebra of the weak derived differential system of D. The problem is reduced, in a sense, to the invariance of this nilpotent symbol algebra under Kähler deformation. In our earlier works in relation to the question of the integrability of distributions spanned by varieties of minimal rational tangents we have established identities on Lie brackets using integral surfaces arising from pencils of rational curves. In the case on hand, at a point oε G / P we prove that the nilpotent symbol algebra at o is nothing other than the universal Lie algebra generated by Do subject to these identities on Lie brackets, by verifying that they correspond to finiteness condition in the Serre presentation of the simple Lie algebra G. © 2002 Éditions scientifiques et médicales Elsevier SAS.postprin

Automorphism groups of spaces of minimal rational curves on Fano manifolds of Picard number 1

Let X be a Fano manifold of Picard number 1 and M an irreducible component of the space of minimal rational curves on X. It is a natural problem to understand the extent to which the geometry of X is captured by the geometry of M. In this vein we raise the question as to whether the canonical map Aut o(X) → Auto (M) is an isomorphism. After providing a number of examples showing that this may fail in general, we show that the map is indeed an isomorphism under the additional assumption that the subvariety of M consisting of members passing through a general point x ∈ X is irreducible and of dimension ≥ 2.published_or_final_versio

Finite morphisms onto Fano manifolds of Picard number 1 which have rational curves with trivial normal bundles

Let X be a Fano manifold of Picard number 1 admitting a rational curve with trivial normal bundle and f : X′ → X be a generically finite surjective holomorphic map from a projective manifold X′ onto X. When the domain manifold X′ is fixed and the target manifold X is a priori allowed to deform we prove that the holomorphic map f : X′ → X is locally rigid up to biholomorphisms of target manifolds. This result complements, with a completely different method of proof, an earlier local rigidity theorem of ours (see J. Math. Pures Appl. 80 (2001), 563-575) for the analogous situation where the target manifold X is a Fano manifold of Picard number 1 on which there is no rational curve with trivial normal bundle. In another direction, given a Fano manifold X′ of Picard number 1, we prove a finiteness result for generically finite surjective holomorphic maps of X′ onto Fano manifolds (necessarily of Picard number 1) admitting rational curves with trivial normal bundles. As a consequence, any 3-dimensional Fano manifold of Picard number 1 can only dominate a finite number of isomorphism classes of projective manifolds.published_or_final_versio

Ab initio calculations on SF₂ and its low-lying cationic states : anharmonic Franck-Condon simulation of the uv photoelectron spectrum of SF₂

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Franck-Condon simulation of the single-vibronic-level emission spectra of HPCI/DPCI and the chemiluminescence spectrum of HPCI, including anharmonicity

2004-2005 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Ab initio calculations on SCl₂ and low-lying cationic states of SCl₂⁺ : Franck-Condon simulation of the UV photoelectron spectrum of SCl₂

Author name used in this publication: F. T. Chau2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe