中文
相关论文

相关论文: The Cheltsov--Rubinstein problem for strongly asym…

200 篇论文

We classify smooth weak del Pezzo surfaces with global vector fields over an arbitrary algebraically closed field $k$ of arbitrary characteristic $p \geq 0$. We give a complete description of the configuration of $(-1)$- and $(-2)$-curves…

代数几何 · 数学 2024-12-25 Gebhard Martin , Claudia Stadlmayr

We prove the existence of Kahler-Einstein metrics on a nonsingular section of the Grassmannian $\mathrm{Gr}(2, 5)\subset\mathbb{P}^9$ by a linear subspace of codimension 3, and the Fermat hypersurface of degree 6 in $\mathbb{P}(1,1,1,2,3)$.…

代数几何 · 数学 2009-02-08 Ivan Cheltsov , Constantin Shramov

The main result is that a quasi-projective surface has negative log Kodaira dimension (i.e. no log pluricanonical sections) iff it is dominated by images of the affine line. This follows from our main intermediate result, that the smooth…

alg-geom · 数学 2008-02-03 Sean Keel , James McKernan

In this article, we study the divisor classes of del Pezzo surfaces, which are written as the sum of distinct lines with fixed intersection according to the inscribed simplexes and crosspolytopes in Gosset polytopes. We introduce the…

代数几何 · 数学 2010-01-26 Jae-Hyouk Lee

Using the Abban-Zhuang theory and the classification of three-dimensional log smooth log Fano pairs due to Maeda, we prove that threefold log Fano pairs $(X, D)$ of Maeda type with reducible boundary $D$ are K-unstable, with four…

代数几何 · 数学 2023-02-10 Konstantin Loginov

We study log canonical thresholds (also called global log canonical threshold or $\alpha$-invariant) of $\mathbb{R}$-linear systems. We prove existence of positive lower bounds in different settings, in particular, proving a conjecture of…

代数几何 · 数学 2020-12-02 Caucher Birkar

We study Fano 3-folds with Fano index 2: that is, 3-folds X with rank Pic(X) = 1, Q-factorial terminal singularities and -K_X = 2A for an ample Weil divisor A. We give a first classification of all possible Hilbert series of such polarised…

代数几何 · 数学 2007-05-23 Gavin Brown , Kaori Suzuki

We provide a sufficient condition for polarisations of Fano varieties to be K-stable in terms of Tian's alpha invariant, which uses the log canonical threshold to measure singularities of divisors in the linear system associated to the…

代数几何 · 数学 2016-04-21 Ruadhaí Dervan

We show that fixed dimensional klt weak Fano pairs with alpha-invariants and volumes bounded away from $0$ and the coefficients of the boundaries belong to the set of hyperstandard multiplicities $\Phi(\mathscr{R})$ associated to a fixed…

代数几何 · 数学 2018-10-24 Weichung Chen

We construct two types of wellformed and quasismooth biregular models (infinite series) of rigid orbifold del Pezzo surfaces having their (sub) anti-canonical embeddings in $\mathbb P^6(w_i) $. One type of model contains a family of rigid…

代数几何 · 数学 2025-06-26 Muhammad Imran Qureshi

The regularity of systolically extremal surfaces is a notoriously difficult problem already discussed by M. Gromov in 1983, who proposed an argument toward the existence of $L^2$-extremizers exploiting the theory of $r$-regularity developed…

微分几何 · 数学 2019-05-15 Mikhail Katz , Stephane Sabourau

Del Pezzo surfaces over C with log terminal singularities of index \le 2 were classified by Alekseev and Nikulin. In this paper, for each of these surfaces, we find an appropriate morphism to projective space. These morphisms enable us to…

代数几何 · 数学 2007-05-23 Grzegorz Kapustka , Michal Kapustka

We provide explicit graded constructions of orbifold del Pezzo surfaces with rigid orbifold points of type $\left\{k_i\times\frac{1}{r_i}(1,a_i): 3\le r_i \le 10,k_i \in \ZZ_{\ge 0}\right\}$; as well-formed and quasismooth varieties…

代数几何 · 数学 2020-09-14 Muhammad Imran Qureshi

We develop a framework to study the K-stability of weighted Fano hypersurfaces based on a combination of birational and convex-geometric techniques. As an application, we prove that all quasi-smooth weighted Fano hypersurfaces of index 1…

代数几何 · 数学 2026-01-07 Livia Campo , Kento Fujita , Taro Sano , Luca Tasin

In this paper, we study 170 families of quiver flag zero loci Fano fourfolds as described by Kalashnikov. We interpret those manifolds as zero loci of sections of homogeneous vector bundles in homogeneous varieties, and we give a birational…

代数几何 · 数学 2024-06-10 Enrico Fatighenti , Fabio Tanturri , Federico Tufo

Quadratic Gromov--Witten invariants allow one to obtain an arithmetically meaningful count of curves satisfying constraints over a field $k$ without assuming that $k$ is the field of complex or real numbers. This paper studies the behavior…

代数几何 · 数学 2025-06-24 Erwan Brugallé , Kirsten Wickelgren

Building upon the classification by Lacini [arXiv:2005.14544], we determine the isomorphism classes of log del Pezzo surfaces of rank one over an algebraically closed field of characteristic five either which are not log liftable over the…

代数几何 · 数学 2025-10-01 Masaru Nagaoka

We study Fano varieties endowed with a faithful action of a symmetric group, as well as analogous results for Calabi--Yau varieties, and log terminal singularities. We show the existence of a constant $m(n)$, so that every symmetric group…

代数几何 · 数学 2025-02-05 Louis Esser , Lena Ji , Joaquín Moraga

The aim of this paper is to prove Golyshev's conjecture in the cases of Fano threefolds $V_{10}$ and $V_{14}$. This conjecture states modularity of D3 equations for smooth Fano threefolds with Picard group Z. More precisely, we find…

代数几何 · 数学 2007-07-25 Victor Przyjalkowski

We prove several boundedness statements for geometrically integral normal del Pezzo surfaces $X$ over arbitrary fields. We give an explicit sharp bound on the irregularity if $X$ is canonical or regular. In particular, we show that wild…

代数几何 · 数学 2025-04-23 Fabio Bernasconi , Gebhard Martin