中文
相关论文

相关论文: The number of vertices of a Fano polytope

200 篇论文

Given a set $S \subseteq \mathbb{R}^d$, a hollow polytope has vertices in $S$ but contains no other point of $S$ in its interior. We prove upper and lower bounds on the maximum number of vertices of hollow polytopes whose facets are…

度量几何 · 数学 2025-04-25 Srinivas Arun , Travis Dillon

In this note we show that the maximum number of vertices in any polyhedron $P=\{x\in \mathbb{R}^d : Ax\leq b\}$ with $0,1$-constraint matrix $A$ and a real vector $b$ is at most $d!$.

计算几何 · 计算机科学 2007-05-23 Khaled Elbassioni , Zvi Lotker , Raimund Seidel

In this article, we determine all equivariant compactifications of the three-dimensional vector group $\mathbf{G}_a^3$ which are smooth Fano threefolds with Picard number greater or equal than two.

代数几何 · 数学 2019-12-20 Zhizhong Huang , Pedro Montero

We prove that a smooth well formed Picard rank one Fano complete intersection of dimension at least 2 in a toric variety is a weighted complete intersection.

代数几何 · 数学 2023-02-08 Victor Przyjalkowski , Constantin Shramov

Fine and Gill (1973) introduced the geometric representation for those comparative probability orders on n atoms that have an underlying probability measure. In this representation every such comparative probability order is represented by…

组合数学 · 数学 2023-08-23 Ilya Chevyrev , Dominic Searles , Arkadii Slinko

As a variant of the famous Tur\'an problem, we study $\mathrm{rex}(n,F)$, the maximum number of edges that an $n$-vertex regular graph can have without containing a copy of $F$. We determine $\mathrm{rex}(n,K_{r+1})$ for all pairs of…

组合数学 · 数学 2019-12-24 Dániel Gerbner , Balázs Patkós , Zsolt Tuza , Máté Vizer

A conjecture of Pukhlikov states that a smooth Fano variety of dimension at least four and index one is birationally rigid. We show that a general member of the linear system given by the ample generator of the Picard group of the moduli…

代数几何 · 数学 2007-05-23 Ana-Maria Castravet

Over an algebraically closed field of positive characteristic, we classify smooth Fano threefolds of Picard number one whose anti-canonical linear systems are not very ample. Furthermore, we also prove that an anti-canonically embedded Fano…

代数几何 · 数学 2026-03-13 Hiromu Tanaka

We construct Fano threefolds with very ample anti-canonical bundle and Picard rank greater than one from cracked polytopes - polytopes whose intersection with a complete fan forms a set of unimodular polytopes - using Laurent inversion; a…

代数几何 · 数学 2019-07-30 Thomas Prince

We classify the non-toric, $\mathbb{Q}$-factorial, Gorenstein, Fano threefolds of Picard number one with an effective $\mathbb{K}^*$-action and maximal orbit quotient $\mathbb{P}_2$.

代数几何 · 数学 2025-01-22 Marco Ghirlanda

Let $U\subset \mathbb P^N$ be a projective variety which is not a cone and whose hyperplane sections are smooth Enriques surfaces. We prove that the degree of a $U$ is at most 32 and the bound is sharp.

代数几何 · 数学 2015-06-26 Yuri Prokhorov

Iterating the procedure of making a double cover over a given variety, we construct large families of smooth higher-dimensional Fano varieties of index 1. These varieties can be realized as complete intersections in various weighted…

代数几何 · 数学 2015-06-26 Aleksandr V. Pukhlikov

Suppose that X is a Fano manifold that corresponds under Mirror Symmetry to a Laurent polynomial f, and that P is the Newton polytope of f. In this setting it is expected that there is a family of algebraic varieties over the unit disc with…

代数几何 · 数学 2019-12-11 Tom Coates , Alessio Corti , Genival da Silva

We investigate the maximum number of intersections between two polygons with p and q vertices, respectively, in the plane. The cases where p or q is even or the polygons do not have to be simple are quite easy and already known, but when p…

组合数学 · 数学 2015-02-11 Felix Günther

We investigate Fano varieties defined over a number field that contain subvarieties whose number of rational points of bounded height is comparable to the total number on the variety.

数论 · 数学 2017-03-23 T. D. Browning , D. Loughran

We show that complex Fano hypersurfaces can have arbitrarily large degrees of irrationality. More precisely, if we fix a Fano index e, then the degree of irrationality of a very general complex Fano hypersurface of index e and dimension n…

代数几何 · 数学 2021-11-11 Nathan Chen , David Stapleton

Let X be a smooth Fano variety of dimension at least 4. We show that if X has an elementary birational contraction sending a divisor to a curve, then the Picard number of X is smaller or equal to 5.

代数几何 · 数学 2008-07-16 C. Casagrande

We find at least 527 new four-dimensional Fano manifolds, each of which is a complete intersection in a smooth toric Fano manifold.

代数几何 · 数学 2022-10-28 Tom Coates , Alexander Kasprzyk , Thomas Prince

We show that Fano lattice polygons define a class of balanced quivers with interesting properties. The combinatorics of these quivers is related to singularities of the underlying toric Fano surface. This allows us to show that every Fano…

代数几何 · 数学 2019-07-23 Mohammad E. Akhtar

Complete intersections inside rational homogeneous varieties provide interesting examples of Fano manifolds. For example, if $X = \cap_{i=1}^r D_i \subset G/P$ is a general complete intersection of $r$ ample divisors such that $K_{G/P}^*…

代数几何 · 数学 2018-08-07 Chenyu Bai , Baohua Fu , Laurent Manivel