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Related papers: Exceptional Collections for Toric Fano Fourfolds

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We study quartic double fivefolds from the perspective of Fano manifolds of Calabi-Yau type and that of exceptional quaternionic representations. We first prove that the generic quartic double fivefold can be represented, in a finite number…

Algebraic Geometry · Mathematics 2017-10-13 Roland Abuaf

On smooth projective varieties of dimension $d$, $d$-tilting bundles are important in both geometry and representation theory, since they provide a bridge from the geometry of such varieties to the derived McKay correspondence and to higher…

Algebraic Geometry · Mathematics 2026-05-28 Ryu Tomonaga

We give a short, new proof of a recent result of Hanlon-Hicks-Lazarev about toric varieties. As in their work, this leads to a proof of a conjecture of Berkesch-Erman-Smith on virtual resolutions and to a resolution of the diagonal in the…

Algebraic Geometry · Mathematics 2024-05-15 Michael K. Brown , Daniel Erman

In this paper, we obtain a complete classification of smooth toric Fano varieties equipped with extremal contractions which contract divisors to curves for any dimension. As an application, we obtain a complete classification of smooth…

Algebraic Geometry · Mathematics 2007-05-23 Hiroshi Sato

Let $X$ be a nonsingular complex projective toric variety. We address the question of semi-stability as well as stability for the tangent bundle $T{X}$. In particular, a complete answer is given when $X$ is a Fano toric variety of dimension…

Algebraic Geometry · Mathematics 2021-12-17 Indranil Biswas , Arijit Dey , Ozhan Genc , Mainak Poddar

We show that the moduli space of elliptic curves of minimal degree in a general Fano variety of lines of a cubic fourfold is a non-singular curve of genus $631$. The curve admits a natural involution with connected quotient. We find that…

Algebraic Geometry · Mathematics 2020-01-20 Denis Nesterov , Georg Oberdieck

Using an explicit resolution of the diagonal for the variety V_5, we provide cohomological characterizations of the universal and quotient bundles. A splitting criterion for bundles over V_5 is also proved. The presentation of semistable…

Algebraic Geometry · Mathematics 2007-05-23 Daniele Faenzi

Inspired by Fujita's algebro-geometric result that complex projective space has maximal degree among all K-semistable complex Fano varieties, we conjecture that the height of a K-semistable metrized arithmetic Fano variety X of relative…

Algebraic Geometry · Mathematics 2024-11-20 Rolf Andreasson , Robert J. Berman

We construct a full strong exceptional collection consisting of line bundles on any two-dimensional smooth toric weak Fano stack. The total endomorphism algebra of the resulting collection is isomorphic to the path algebra of a quiver with…

Algebraic Geometry · Mathematics 2011-05-31 Akira Ishii , Kazushi Ueda

In this paper we consider double covers of the projective space in relation with the problem of extensions of varieties, specifically of extensions of canonical curves to $K3$ surfaces and Fano 3-folds. In particular we consider $K3$…

Algebraic Geometry · Mathematics 2022-05-17 Ciro Ciliberto , Thomas Dedieu

In the mid 70's, Hartshorne conjectured that, for all n > 7, any rank 2 vector bundles on P^n is a direct sum of line bundles. This conjecture remains still open. In this paper, we construct indecomposable rank two vector bundles on a large…

Algebraic Geometry · Mathematics 2013-07-12 Giulio Cotignoli , Alexandru Sterian

Let X be a smooth complex Fano 4-fold. We show that if X has a small elementary contraction, then the Picard number rho(X) of X is at most 12. This result is based on a careful study of the geometry of X, on which we give a lot of…

Algebraic Geometry · Mathematics 2022-05-20 C. Casagrande

For any toric ideal $I$ in a polynomial ring $S$, we provide a combinatorial description of a free resolution of the integral closure of the $S$-module $S/I$. These new complexes arise from an extension of Bayer--Sturmfels' theory of…

Commutative Algebra · Mathematics 2025-12-22 Christine Berkesch , Lauren Cranton Heller , Gregory G. Smith , Jay Yang

We show how to construct tilting bundles for a class of smooth projective varieties using characteristic $p$ methods. Given such a variety $X$, reduce it modulo a prime number and consider the direct image of the structure sheaf under the…

Algebraic Geometry · Mathematics 2010-01-24 Alexander Samokhin

For a toric Fano manifold $X$ denote by $Crit(X) \subset (\mathbb{C}^{\ast})^n$ the solution scheme of the Landau-Ginzburg system of equations of $X$. Examples of toric Fano manifolds with $rk(Pic(X)) \leq 3$ which admit full strongly…

Algebraic Geometry · Mathematics 2017-05-22 Yochay Jerby

A conjecture of Bondal-Polishchuk states that, in particular for the bounded derived category of coherent sheaves on a smooth projective variety, the action of the braid group on full exceptional collections is transitive up to shifts. We…

Algebraic Geometry · Mathematics 2024-08-01 Johannes Krah

In the paper "Birational geometry via moduli spaces" by I. Cheltsov, L. Katzarkov, and V. Przyjalkowski a new structure connecting toric degenerations of smooth Fano threefolds by projections was introduced; using Mirror Symmetry these…

Algebraic Geometry · Mathematics 2019-04-05 Alexander Kasprzyk , Ludmil Katzarkov , Victor Przyjalkowski , Dmitrijs Sakovics

We call a sheaf on an algebraic variety immaculate if it lacks any cohomology including the zero-th one, that is, if the derived version of the global section functor vanishes. Such sheaves are the basic tools when building exceptional…

Algebraic Geometry · Mathematics 2018-08-29 Klaus Altmann , Jarosław Buczyński , Lars Kastner , Anna-Lena Winz

We prove the Yau-Tian-Donaldson's conjecture for any $\mathbb{Q}$-Fano variety that has a log smooth resolution of singularities such that the discrepancies of all exceptional divisors are non-positive. In other words, if such a Fano…

Differential Geometry · Mathematics 2021-03-30 Chi Li , Gang Tian , Feng Wang

In an unpublished preprint, A. King conjectured that there are tilting bundles over projective varieties which are obtained as invariant quotients of affine spaces for linear actions of reductive groups. The goal of this paper is to give…

Algebraic Geometry · Mathematics 2009-06-19 Mihai Halic