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Over a smooth projective toric variety we study toric sheaves, that is, reflexive sheaves equivariant with respect to the acting torus, from a polyhedral point of view. One application is the explicit construction of the torus invariant…

Algebraic Geometry · Mathematics 2024-12-24 Klaus Altmann , Andreas Hochenegger , Frederik Witt

In this note we show that the positivity property of the equivariant signature of the loop space, first observed in [MS1] in the case of the even-dimensional projective spaces, is valid for Picard number 2 toric varieties. A new formula for…

Algebraic Topology · Mathematics 2007-05-23 V. Gorbounov , F. Malikov

We determine the homeomorphism type of the set of real points of a smooth projective toric surface. This note may serve as an expository introduction to some of the ideas and techniques in C. Delaunay's work on real toric varieties.

Algebraic Geometry · Mathematics 2007-05-23 Sam Payne

In this short note, we investigate the existence of orbifold K\"ahler-Einstein metrics on toric varieties. In particular, we show that every $\mathbb{Q}$-factorial normal projective toric variety allows an orbifold K\"ahler-Einstein metric.…

Algebraic Geometry · Mathematics 2022-11-15 Lukas Braun

We study the GKM theory for a equivariant stratified space having orbifold structures in tis successive quotients. Then, we introduce the notion of an \emph{almost simple polytope}, as well as a \emph{divisive toric variety} generalizing…

Algebraic Topology · Mathematics 2020-12-03 Soumen Sarkar , Jongbaek Song

We study global primary decompositions in the category of sheaves on a scheme which are equivariant under the action of an algebraic group. We show that equivariant primary decompositions exist if the group is connected. As main application…

Algebraic Geometry · Mathematics 2012-01-30 Markus Perling , Guenther Trautmann

We describe classes of toric varieties of codimension 2 which are either minimally defined by 3 binomial equations over any algebraically closed field, or are set-theoretic complete intersections in exactly one positive characteristic.

Commutative Algebra · Mathematics 2007-06-28 Margherita Barile

We classify the invariant prime ideals of a quantum partial flag variety under the action of the related maximal torus. As a result we construct a bijection between them and the torus orbits of symplectic leaves of the standard Poisson…

Quantum Algebra · Mathematics 2009-10-07 Milen Yakimov

Given a derived equivalence of orbifolds associated to projective varieties with (not necessarily Gorenstein) quotient singularities, we deduce consequences related to the behavior of orbifold Hodge numbers and the Picard variety, extending…

Algebraic Geometry · Mathematics 2013-06-11 Mihnea Popa

In stochastic analysis, a standard method to study a path is to work with its signature. This is a sequence of tensors of different order that encode information of the path in a compact form. When the path varies, such signatures…

Algebraic Geometry · Mathematics 2020-08-25 Laura Colmenarejo , Francesco Galuppi , Mateusz Michałek

We prove that smooth projective varieties with equivalent derived categories have isogenous (and sometimes isomorphic) Picard varieties. In particular their irregularity and number of independent vector fields are the same. This is turn…

Algebraic Geometry · Mathematics 2010-10-26 Mihnea Popa , Christian Schnell

We classify the real tight contact structures on solid tori up to equivariant contact isotopy and apply the results to the classification of real tight structures on $S^3$ and real lens spaces $L(p,\pm 1)$. We prove that there is a unique…

Geometric Topology · Mathematics 2025-08-25 Sinem Onaran , Ferit Öztürk

We construct explicit complex structures and transversely K\"ahler holomorphic foliations on $SU(3)$ corresponding to variations of real quadratic equations on a complex quadric in $\mathbb{C}^{6}$ as generalizations of left-invariant…

Complex Variables · Mathematics 2024-09-19 Hiroaki Ishida , Hisashi Kasuya

We study Fourier-Mukai transforms for smooth projective varieties whose canonical bundles have finite order, and relate them to equivariant transforms on certain finite covering spaces. Our results lead to new equivalences of derived…

Algebraic Geometry · Mathematics 2007-05-23 Tom Bridgeland , Antony Maciocia

The geometric and algebraic properties of smooth projective varieties with 1-regular structure sheaf are well understood, and the complete classification of these varieties is a classical result. The aim of this paper is to study the next…

Algebraic Geometry · Mathematics 2018-03-06 Sijong Kwak , Jinhyung Park

We construct orbifolds with quasitoric boundary and show that they have stable almost complex structure. We show that a quasitoric orbifold is complex cobordant to finite disjoint copies of complex orbifold projective spaces. Finally some…

Algebraic Topology · Mathematics 2016-02-01 Soumen Sarkar

We identify the category of real mixed Hodge structures with the category of vector bundles with connections (not necessarily flat) on C, equivariant with respect to C^*. Here C is the complex plane considered as a 2-dimensional real…

Algebraic Geometry · Mathematics 2010-07-13 Mikhail Kapranov

In this paper, we investigate tropical secant varieties of ordinary linear spaces. These correspond to the log-limit sets of ordinary toric varieties; we show that their interesting parts are combinatorially isomorphic to a certain natural…

Combinatorics · Mathematics 2007-05-23 Mike Develin

We construct quasitoric manifolds of dimension 6 and higher which are not equivariantly homeomorphic to any toric origami manifold. All necessary topological definitions and combinatorial constructions are given and the statement is…

Algebraic Topology · Mathematics 2015-05-08 Anton Ayzenberg , Mikiya Masuda , Seonjeong Park , Haozhi Zeng

A spectral sequence calculating the homology groups of some spaces of maps equivariant under compact group actions is described. For the main example, we calculate the rational homology groups of spaces of even and odd maps $S^m \to S^M$,…

Algebraic Topology · Mathematics 2021-07-01 Victor Vassiliev