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Geometric Invariant Theory and Generalized Eigenvalue Problem II

Nicolas Ressayre (2011)

Annales de l’institut Fourier

Let G be a connected reductive subgroup of a complex connected reductive group G ^ . Fix maximal tori and Borel subgroups of G and G ^ . Consider the cone ( G , G ^ ) generated by the pairs ( ν , ν ^ ) of strictly dominant characters such that V ν * is a submodule of V ν ^ . We obtain a bijective parametrization of the faces of ( G , G ^ ) as a consequence of general results on GIT-cones. We show how to read the inclusion of faces off this parametrization.

Good moduli spaces for Artin stacks

Jarod Alper (2013)

Annales de l’institut Fourier

We develop the theory of associating moduli spaces with nice geometric properties to arbitrary Artin stacks generalizing Mumford’s geometric invariant theory and tame stacks.

Harder-Narasimhan filtrations and optimal destabilizing vectors in complex geometry

Laurent Bruasse, Andrei Teleman (2005)

Annales de l’institut Fourier

We give here a generalization of the theory of optimal destabilizing 1-parameter subgroups to non algebraic complex geometry : we consider holomorphic actions of a complex reductive Lie group on a finite dimensional (possibly non compact) Kähler manifold. In a second part we show how these results may extend in the gauge theoretical framework and we discuss the relation between the Harder-Narasimhan filtration and the optimal detstabilizing vectors of a non semistable object....

Hilbert schemes and stable pairs: GIT and derived category wall crossings

Jacopo Stoppa, Richard P. Thomas (2011)

Bulletin de la Société Mathématique de France

We show that the Hilbert scheme of curves and Le Potier’s moduli space of stable pairs with one dimensional support have a common GIT construction. The two spaces correspond to chambers on either side of a wall in the space of GIT linearisations. We explain why this is not enough to prove the “DT/PT wall crossing conjecture” relating the invariants derived from these moduli spaces when the underlying variety is a 3-fold. We then give a gentle introduction to a small part of Joyce’s theory for such...

Invariant subspaces for grasping internal forces and non-interacting force-motion control in robotic manipulation

Paolo Mercorelli (2012)

Kybernetika

This paper presents a parametrization of a feed-forward control based on structures of subspaces for a non-interacting regulation. With advances in technological development, robotics is increasingly being used in many industrial sectors, including medical applications (e. g., micro-manipulation of internal tissues or laparoscopy). Typical problems in robotics and general mechanisms may be mathematically formalized and analyzed, resulting in outcomes so general that it is possible to speak of structural...

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