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Related papers: Exceptional Collections for Toric Fano Fourfolds

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Given a collection of line bundles on a complete toric variety, the Macaulay2 package QuiversToricVarieties contains functions to construct its quiver of sections and check whether the collection is strong exceptional. It contains a…

Algebraic Geometry · Mathematics 2015-01-27 Nathan Prabhu-Naik

For any $n\geq 3$, we explicitly construct smooth projective toric $n$-folds of Picard number $\geq 5$, where any nontrivial nef line bundles are big.

Algebraic Geometry · Mathematics 2008-10-24 Osamu Fujino , Hiroshi Sato

There exist exactly 166 4-dimensional reflexive polytopes such that the corresponding 4-dimensional Gorenstein toric Fano varieties have at worst terminal singularities in codimension 3 and their anticanonical divisor is divisible by 2. For…

Algebraic Geometry · Mathematics 2017-08-23 Victor Batyrev , Maximilian Kreuzer

We generalize Givental's Theorem for complete intersections in smooth toric varieties in the Fano case. In particular, we find Gromov--Witten invariants of Fano varieties of dimension $\geq 3$, which are complete intersections in weighted…

Algebraic Geometry · Mathematics 2018-08-07 Victor Przyjalkowski

In this note we apply the techniques of the toric systems introduced by Hille-Perling to several problems on smooth projective surfaces: We showed that the existence of full exceptional collection of line bundles implies the rationality for…

Algebraic Geometry · Mathematics 2017-11-28 Shizhuo Zhang

We propose a concept of truncation for arbitrary smooth projective toric varieties and construct explicit cellular resolutions for nef truncations of their total coordinate rings. We show that these resolutions agree with the short…

Algebraic Geometry · Mathematics 2025-09-09 Lauren Cranton Heller

We classify all complete non-singular toric varieties with Picard number four via a combinatorial framework based on fanlike simplicial spheres and characteristic maps. This classification yields $59$ fanlike seeds with Picard number four,…

Algebraic Geometry · Mathematics 2025-04-28 Suyoung Choi , Hyeontae Jang , Mathieu Vallée

We show that Fano 4-folds with Picard number 5 have Lefschetz defect 3 if and only if they are toric of combinatorial type K. We also find a characterization for such varieties in terms of Picard number of prime divisors. Moreover, we…

Algebraic Geometry · Mathematics 2020-07-22 Eleonora Anna Romano

We construct minimal resolutions of pushforwards of structure sheaves of toric substacks of smooth toric stacks by line bundles as strong deformation retracts of cellular resolutions constructed by Hanlon, Hicks and Lazarev. We also provide…

Algebraic Geometry · Mathematics 2026-04-30 Zengrui Han

In this paper, we investigate when there exists a wild hypersurface bundle over a smooth proper toric variety in positive characteristic. In particular, we determine the possibilities for toric varieties with Picard number at most three or…

Algebraic Geometry · Mathematics 2007-05-23 Hiroshi Sato

In this paper we study the geometry of mildly singular Fano varieties on which there is an effective prime divisor of Picard number one. Afterwards, we address the case of toric varieties. Finally, we treat the lifting of extremal…

Algebraic Geometry · Mathematics 2017-09-07 Pedro Montero

In this paper we explain the complete biregular classification of all 4-dimensional smooth toric Fano varieties. The main result states that there exist exactly 123 different types of toric Fano 4-folds up to isomorphism.

Algebraic Geometry · Mathematics 2007-05-23 Victor V. Batyrev

In this paper we study smooth toric Fano varieties using primitive relations and toric Mori theory. We show that for any irreducible invariant divisor D in a toric Fano variety X, we have $0\leq\rho_X-\rho_D\leq 3$, for the difference of…

Algebraic Geometry · Mathematics 2007-05-23 Cinzia Casagrande

We consider projective Hyper-K\"ahler manifolds of dimension four that are deformation equivalent to Hilbert squares of K3 surfaces. In case such a manifold admits a divisorial contraction, the exceptional divisor is a conic bundle over a…

Algebraic Geometry · Mathematics 2025-04-07 Federica Galluzzi , Bert Van Geemen

Real Legendrian subvarieties are classical objects of differential geometry and classical mechanics and they have been studied since antiquity. However, complex Legendrian subvarieties are much more rigid and have more exceptional…

Algebraic Geometry · Mathematics 2013-05-16 Jarosław Buczyński

We give a complete classification of smooth, complex projective Fano 4-folds of Picard number 3 having a prime divisor of Picard number 1. They form 28 distinct families, and we compute the main numerical invariants, study the base locus of…

Algebraic Geometry · Mathematics 2023-03-24 Saverio Andrea Secci

In this paper, we advance the classification of toric 2-Fano manifolds by continuing the investigation of the minimal projective bundle dimension $m(X) \in \{1,\dots,\dim(X)\}$ introduced in our previous work. This invariant captures the…

We find a characterization for Fano 4-folds $X$ with Lefschetz defect $\delta_{X}=3$: besides the product of two del Pezzo surfaces, they correspond to varieties admitting a conic bundle structure $f\colon X\to Y$ with…

Algebraic Geometry · Mathematics 2019-06-26 Pedro Montero , Eleonora Anna Romano

We exhibit full exceptional collections of vector bundles on any smooth, Fano arithmetic toric variety whose split fan is centrally symmetric.

Algebraic Geometry · Mathematics 2020-06-17 Matthew R Ballard , Alexander Duncan , Patrick K. McFaddin

For a Fano threefold admitting a full exceptional collection of vector bundles of length four we show that all full exceptional collections consist of shifted vector bundles. We prove this via a detailed study of the group generated by…

Algebraic Geometry · Mathematics 2026-02-16 Anya Nordskova , Michel Van den Bergh