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Related papers: Minimal log discrepancy and orbifold curves

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We prove existence of partitions of an open set $\Omega$ with a given number of phases, which minimize the sum of the fractional perimeters of all the phases, with Dirichlet boundary conditions. In two dimensions we show that, if the…

Analysis of PDEs · Mathematics 2020-04-24 Annalisa Cesaroni , Matteo Novaga

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…

Algebraic Geometry · Mathematics 2019-06-28 Aleksandr V. Pukhlikov

We prove that a log surface has only finitely many weakly log canonical projective models with klt singularities up to log isomorphism, by reducing the problem to the boundedness of their polarization.

Algebraic Geometry · Mathematics 2025-10-17 Daniil Serebrennikov

By a heuristic argument, we relate two conjectures. One is a version of Manin's conjecture about the distribution of rational points on a Fano variety. We concern specific singular Fano varieties, namely quotients of projective spaces by…

Number Theory · Mathematics 2015-05-19 Takehiko Yasuda

We show that any collection of n-dimensional orbifolds with sectional curvature and volume uniformly bounded below, diameter bounded above, and with only isolated singular points contains orbifolds of only finitely many orbifold…

Differential Geometry · Mathematics 2011-06-15 Emily Proctor

We study a particular class of rationally connected manifolds, $X\subset \p^N$, such that two general points $x,x' \in X$ may be joined by a conic contained in $X$. We prove that these manifolds are Fano, with $b_2\leq 2$. Moreover, a…

Algebraic Geometry · Mathematics 2012-09-11 Paltin Ionescu , Francesco Russo

For certain quasismooth Calabi-Yau hypersurfaces in weighted projective space, the Berglund-H\"{u}bsch-Krawitz (BHK) mirror symmetry construction gives a concrete description of the mirror. We prove that the minimal log discrepancy of the…

Algebraic Geometry · Mathematics 2024-01-30 Louis Esser

Using a variational approach, we establish the equivalence between a weighted volume minimization principle and the existence of a conical Calabi-Yau structure on horospherical cones with mild singularities. This allows us to do explicit…

Differential Geometry · Mathematics 2023-04-25 Tran-Trung Nghiem

We show that the minimal log discrepancy of any $\mathbb Q$-Gorenstein non-canonical threefold is $\leq\frac{12}{13}$, which is an optimal bound.

Algebraic Geometry · Mathematics 2020-11-10 Jihao Liu , Liudan Xiao

We study various measures of irrationality for hypersurfaces of large degree in projective space and other varieties. These include the least degree of a rational covering of projective space, and the minimal gonality of a covering family…

Algebraic Geometry · Mathematics 2019-02-20 Francesco Bastianelli , Pietro De Poi , Lawrence Ein , Robert Lazarsfeld , Brooke Ullery

For Fano varieties of various singularities such as canonical and terminal, we construct examples with large Fano index. By low-dimensional evidence, we conjecture that our examples have the largest Fano index for all dimensions.

Algebraic Geometry · Mathematics 2023-08-15 Chengxi Wang

We show that there exists a positive real number $\delta>0$ such that for any normal quasi-projective $\mathbb{Q}$-Gorenstein $3$-fold $X$, if $X$ has worse than canonical singularities, that is, the minimal log discrepancy of $X$ is less…

Algebraic Geometry · Mathematics 2021-12-24 Chen Jiang

The main purpose of this article is to prove that the family of all Fano threefolds with log-terminal singularities with bounded index is bounded.

alg-geom · Mathematics 2008-02-03 A. Borisov

In this short note, we show that any rational curve passing through the generic point in a moduli space of stable bundles with rank $r$ and fixed determinant on a smooth projective curve of genus $g\ge 4$ has degree (with respect to the…

Algebraic Geometry · Mathematics 2007-05-23 Xiaotao Sun

In arXiv:1503.00125, the authors proved that every complete intersection smooth projective variety $Y$ is a Fano visitor, i.e. its derived category $D^b(Y)$ is equivalent to a full triangulated subcategory of the derived category $D^b(X)$…

Algebraic Geometry · Mathematics 2017-02-14 Young-Hoon Kiem , Kyoung-Seog Lee

Let $E$ be the essential part of the exceptional locus of a good resolution of an isolated, log canonical singularity of index one. We describe the dimension of the dual complex of $E$ in terms of the Hodge type of $H^{n-1}(E, O_E)$, which…

Algebraic Geometry · Mathematics 2013-02-04 Shihoko Ishii

On a smooth manifold, we associate to any closed differential form a mapping cone complex. The cohomology of this mapping cone complex can vary with the de Rham cohomology class of the closed form. We present a novel Morse theoretical…

Differential Geometry · Mathematics 2024-06-21 David Clausen , Xiang Tang , Li-Sheng Tseng

We consider compact connected minimal surfaces, with a pair of boundary curves (not necessarily convex) in distinct planes, that have least-area amongst all orientable surfaces with the same boundary. When the planes containing these two…

Differential Geometry · Mathematics 2008-04-29 Wayne Rossman

We formulate the equivalence problem, in the sense of E. Cartan, for families of minimal rational curves on uniruled projective manifolds. An important invariant of this equivalence problem is the variety of minimal rational tangents. We…

Algebraic Geometry · Mathematics 2009-08-17 Jun-Muk Hwang

We prove a simple equivalence between the virtual count of rational curves in the total space of an anti-nef line bundle and the virtual count of rational curves maximally tangent to a smooth section of the dual line bundle. We conjecture a…

Algebraic Geometry · Mathematics 2020-01-09 Michel van Garrel , Tom Graber , Helge Ruddat