中文
相关论文

相关论文: Canonical and log canonical thresholds of Fano com…

200 篇论文

We show that the global log canonical threshold of generic Fano complete intersections of index 1 and codimension $k$ in ${\mathbb P}^{M+k}$ is equal to 1 if $M\geqslant 3k+4$ and the highest degree of defining equations is at least 8. This…

代数几何 · 数学 2014-12-17 Thomas Eckl , Aleksandr Pukhlikov

We study log canonical thresholds on quartic threefolds, quintic fourfolds, and double spaces. As an application, we show that they have a Kaehler-Einstein metric if they are general.

代数几何 · 数学 2015-01-05 Ivan Cheltsov , Jihun Park , Joonyeong Won

We provide enumerative formulas for the degrees of varieties parameterizing hypersurfaces and complete intersections which contain pro-jective subspaces and conics. Besides, we find all cases where the Fano scheme of the general complete…

代数几何 · 数学 2019-04-18 Ciro Ciliberto , M Zaidenberg

We compute global log canonical thresholds of certain birationally bi-rigid Fano 3-folds embedded in weighted projective spaces as complete intersections of codimension 2 and prove that they admit an orbifold K\"{a}hler-Einstein metric and…

代数几何 · 数学 2019-03-19 In-Kyun Kim , Takuzo Okada , Joonyeong Won

We prove that a Fano complete intersection of codimension $k$ and index 1 in the complex projective space ${\mathbb P}^{M+k}$ for $k\geqslant 20$ and $M\geqslant 8k\log k$ with at most multi-quadratic singularities is birationally…

代数几何 · 数学 2020-01-08 Daniel Evans , Aleksandr Pukhlikov

We compute global log canonical thresholds of some smooth Fano threefolds.

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

We relate the global log canonical threshold of a variety with torus action to the global log canonical threshold of its quotient. We apply this to certain Fano varieties and use Tian's criterion to prove the existence of Kahler-Einstein…

代数几何 · 数学 2013-08-13 Hendrik Süß

In this paper we show that the global (log) canonical threshold of $d$-sheeted covers of the $M$-dimensional projective space of index 1, where $d\geqslant 4$, is equal to one for almost all families (except for a finite set). The varieties…

代数几何 · 数学 2019-06-28 Aleksandr V. Pukhlikov

We investigate the variation of log canonical thresholds in (graded) linear systems. For toric log Fano varieties, we give a sharp lower bound for log canonical thresholds of the anticanonical members in terms of the global minimal log…

代数几何 · 数学 2014-11-12 Florin Ambro

The purpose of this article is to develop techniques for estimating basis log canonical thresholds on logarithmic surfaces. To that end, we develop new local intersection estimates that imply log canonicity. Our main motivation and…

代数几何 · 数学 2024-11-22 Ivan A. Cheltsov , Yanir A. Rubinstein , Kewei Zhang

We compute global log canonical thresholds, or equivalently alpha invariants, of birationally rigid orbifold Fano threefolds embedded in weighted projective spaces as codimension two or three. As an important application, we prove that most…

代数几何 · 数学 2016-04-04 In-Kyun Kim , Takuzo Okada , Joonyeong Won

We study Gorenstein almost Fano threefolds X with canonical singularities and pseudoindex > 1. We show that the maximal Picard number of X is 10 in general, 3 if X is Fano, and 8 if X is toric. Moreover, we characterize the boundary cases.…

代数几何 · 数学 2007-05-23 C. Casagrande , P. Jahnke , I. Radloff

We show that the optimal upper bound for the anticanonical degrees of non-Gorenstein $\mathbb{Q}$-factorial canonical Fano threefolds with Picard number one is 200/3.

代数几何 · 数学 2026-01-21 Minyou Li

Let $X$ be a smooth hypersurface of degree $n\geq 3$ in $\mathbb{P}^n$. We prove that the log canonical threshold of $H\in|-K_X|$ is at least $\frac{n-1}{n}$. Under the assumption of the Log minimal model program, we also prove that a…

代数几何 · 数学 2007-05-23 Ivan Cheltsov , Jihun Park

Consider the Fano scheme $F_k(Y)$ parameterizing $k$-dimensional linear subspaces contained in a complete intersection $Y \subset \mathbb{P}^m$ of multi-degree $\underline{d} = (d_1, \ldots, d_s)$. It is known that, if $t := \sum_{i=1}^s…

代数几何 · 数学 2018-12-18 Francesco Bastianelli , Ciro Ciliberto , Flaminio Flamini , Paola Supino

We provide a complete classification of Fano threefolds X having canonical Gorenstein singularities and the anticanonical degree (-KX)^3 equal 64.

代数几何 · 数学 2014-11-20 Ilya Karzhemanov

We prove that every smooth Fano complete intersection of index $1$ and codimension $r$ in $\mathbb{P}^{n+r}$ is birationally superrigid and K-stable if $n\ge 10r$. We also propose a generalization of Tian's criterion of K-stability and, as…

代数几何 · 数学 2021-02-22 Ziquan Zhuang

We consider the Fano scheme $F_k(X)$ of $k$--dimensional linear subspaces contained in a complete intersection $X \subset \mathbb{P}^n$ of multi--degree $\underline{d} = (d_1, \ldots, d_s)$. Our main result is an extension of a result of…

代数几何 · 数学 2020-09-30 F. Bastianelli , C. Ciliberto , F. Flamini , P. Supino

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

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…

代数几何 · 数学 2018-08-07 Victor Przyjalkowski
‹ 上一页 1 2 3 10 下一页 ›