Добірка наукової літератури з теми "Transformations de Fourier-Mukai"

AbstractThe wall-crossing behavior for Bridgeland’s stability conditions on the derived category of coherent sheaves on K3 or abelian surface is studied. We introduce two types of walls. One is called the wall for categories, where thet-structure encoded by stability condition is changed. The other is the wall for stabilities, where stable objects with prescribed Mukai vector may get destabilized. Some fundamental properties of walls and chambers are studied, including the behavior under Fourier–Mukai transforms. A wall-crossing formula of the counting of stable objects will also be derived. As an application, we will explain previous results on the birational maps induced by Fourier–Mukai transforms on abelian surfaces. These transformations turns out to coincide with crossing walls of certain property.

AbstractWe look at how one can construct from the data of a dimer model a Lagrangian submanifold in $$(\mathbb {C}^*)^n$$ ( C ∗ ) n whose valuation projection approximates a tropical hypersurface. Each face of the dimer corresponds to a Lagrangian disk with boundary on our tropical Lagrangian submanifold, forming a Lagrangian mutation seed. Using this we find tropical Lagrangian tori $$L_{T^2}$$ L T 2 in the complement of a smooth anticanonical divisor of a toric del-Pezzo whose wall-crossing transformations match those of monotone SYZ fibers. An example is worked out for the mirror pair $$(\mathbb {CP}^2{\setminus } E, W), {\check{X}}_{9111}$$ ( CP 2 \ E , W ) , X ˇ 9111 . We find a symplectomorphism of $$\mathbb {CP}^2{\setminus } E$$ CP 2 \ E interchanging $$L_{T^2}$$ L T 2 and a SYZ fiber. Evidence is provided that this symplectomorphism is mirror to fiberwise Fourier–Mukai transform on $${\check{X}}_{9111}$$ X ˇ 9111 .

Abstract Topological defects have long been known to encode symmetries and dualities between physical systems. In the context of string theory, defects have been intensively studied at the level of the worldsheet. Although marked by a number of pioneering milestones, the target space picture of defects is much less understood. In this paper, we show, at the level of the target space, that Poisson-Lie T-duality can be encoded as a topological defect. With this result at hand, we can postulate the kernel capturing the Fourier-Mukai transform associated to the action of Poisson-Lie T-duality on the RR-sector. Topological defects have the remarkable property that they can be fused together or, alternatively, with worldsheet boundary conditions. We study how fusion of the proposed generalised T-duality topological defect consistently leads to the known duality transformations for boundary conditions. Finally, taking a step back from generalised T-duality, we tackle the general problem of understanding the effect of fusion at the level of the target space. We propose to use the framework of Dirac geometry and formulate the fusion of topological defects and D-branes in this language.

AbstractWe define and study the existence of very stable Higgs bundles on Riemann surfaces, how it implies a precise formula for the multiplicity of the very stable components of the global nilpotent cone and its relationship to mirror symmetry. The main ingredients are the Bialynicki-Birula theory of $${\mathbb {C}}^*$$ C ∗ -actions on semiprojective varieties, $${\mathbb {C}}^*$$ C ∗ characters of indices of $${\mathbb {C}}^*$$ C ∗ -equivariant coherent sheaves, Hecke transformation for Higgs bundles, relative Fourier–Mukai transform along the Hitchin fibration, hyperholomorphic structures on universal bundles and cominuscule Higgs bundles.

Dans cette thèse on est intéressé à l'étude des catégories dérivées d'une variété lisse et projective sur un corps. En particulier on étude l'information géométrique et catégorielle d'une variété et sa catégorie dérivée pour mieux comprendre l'ensemble de structures monoïdales qu'on peut munir à la catégorie dérivée. La motivation de ce projet s'inspire en deux théorèmes. L'un c'est le théorème de reconstruction de Bondal-Orlov qu'établisse que la catégorie dérivée d'une variété avec diviseur (anti-)canonique ample est assez pour récupérer la variété. D'un autre côté, on a la construction du spectrum de Balmer qu'utilise le produit tensoriel dérivé pour récupérer un nombre plus grand de variétés à partir de sa catégorie dérivée de complexes parfaits comme une catégorie monoïdale. L'existence de différentes structures monoïdales est par contre garanti par l'existence des variétés avec des catégories dérivées équivalentes. On a pour but alors comprendre quel est le rôle de les produits tensoriels dans l'existence (ou non existence) de ces types de variétés. Les résultats principaux qu'on a obtenu sont : Si X est une variété avec diviseur (anti-)canonique ample, et ⊠ est une structure de catégorie tensoriel triangulée sur Db(X) tel que le spectrum de Balmer Spc(Db(X),⊠) est isomorphe à X, alors pour tous F,G∈Db(X), on a F⊠G≃F⊗G où ⊗ c'est le produit tensoriel dérivée. On utilise le théorème de Morita pour les dg-catégories de Toën pour donner une caractérisation d'une structure tronquée en termes de bimodules sur un produit des dg-algèbres, qu'induisent une structure de catégorie tensoriel triangulée sur la catégorie homotopique. On a étudié la théorie de déformation de ces structures dans le sens de la cohomologie de Davydov-Yetter. On montre qu'il existe une correspondance entre un des groupes de cohomologie et l'ensemble de associateurs dont le produit tensoriel peut s'en déformer. On utilise des techniques à un niveau des catégories triangulées et aussi des perspectives de la théorie des catégories supérieurs comme des dg-catégories et quasi-catégories
In this thesis we are interested in studying derived categories of smooth projective varieties over a field. Concretely, we study the geometric and categorical information from the variety and from it's derived category in order to understand the set of monoidal structures one can equip the derived category with. The motivation for this project comes from two theorems. The first is Bondal-Orlov reconstruction theorem which says that the derived category of a variety with ample (anti-)canonical bundle is enough to recover the variety. On the other hand, we have Balmer's spectrum construction which uses the derived tensor product to recover a much larger number of varieties from it's derived category of perfect complexes as a monoidal category. The existence of different monoidal structure is in turn guaranteed by the existence of varieties with equivalent derived categories. We have as a goal then to understand the role of the tensor products in the existence (or not ) of these sort of varieties. The main results we obtained are If X is a variety with ample (anti-)canonical bundle, and ⊠ is a tensor triangulated category on Db(X) such that the Balmer spectrum Spc(Db(X),⊠) is isomorphic to X, then for any F,G∈Db(X) we have F⊠G≃F⊗G where ⊗ is the derived tensor product. We have used Toën's Morita theorem for dg-categories to give a characterization of a truncated structure in terms of bimodules over a product of dg-algebras, which induces a tensor triangulated category at the level of homotopy categories. We studied the deformation theory of these structures in the sense of Davydov-Yetter cohomology, concretely showing that there is a relationship between one of these cohomology groups and the set of associators that the tensor product can deform into. We utilise techniques at the level of triangulated categories and also perspectives from higher category theory like dg-categories and quasi-categories