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Related papers: Non-vanishing theorem for log canonical pairs

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This paper proposes a Fujita-type freeness conjecture for semi-log canonical pairs. We prove it for curves and surfaces by using the theory of quasi-log schemes and give some effective very ampleness results for stable surfaces and semi-log…

Algebraic Geometry · Mathematics 2017-01-26 Osamu Fujino

We reformulate base point free theorems. Our formulation is flexible and has some important applications. One of the main purposes of this paper is to prove a generalization of the base point free theorem in Fukuda's paper: On numerically…

Algebraic Geometry · Mathematics 2011-02-18 Osamu Fujino

Motivated by Shokurov's ACC Conjecture for log canonical thresholds, we propose an inductive point of view on singularities of pairs, in the case when the ambient variety is smooth. Our main result characterizes the log canonicity of a pair…

Algebraic Geometry · Mathematics 2010-04-23 Mircea Mustata

We prove a base point free theorem for nef and log big divisors on log canonical surfaces.

alg-geom · Mathematics 2008-02-03 Shigetaka Fukuda

The main purpose of this article is to define the notion of DuBois singularities for pairs and proving a vanishing theorem using this new notion. The main vanishing theorem specializes to a new vanishing theorem for resolutions of log…

Algebraic Geometry · Mathematics 2019-04-08 Sándor J. Kovács

We prove the base point free theorem for big line bundles on a three-dimensional log canonical projective pair defined over the algebraic closure of a finite field.

Algebraic Geometry · Mathematics 2016-01-20 Diletta Martinelli , Yusuke Nakamura , Jakub Witaszek

We prove a canonical bundle formula for generically finite morphisms in the setting of generalized pairs (with $\mathbb{R}$-coefficients). This complements Filipazzi's canonical bundle formula for morphisms with connected fibres. It is then…

Algebraic Geometry · Mathematics 2020-11-19 Jingjun Han , Wenfei Liu

Building on results of Koll\'ar, we prove Shokurov's ACC Conjecture for log canonical thresholds on smooth varieties, and more generally, on varieties with quotient singularities.

Algebraic Geometry · Mathematics 2009-01-09 Lawrence Ein , Mircea Mustata

We prove the existence of log canonical modifications for a log pair. As an application, together with Koll\"ar's gluing theory, we remove the assumption in the first named author's work [Odaka11], which shows that K-semistable polarized…

Algebraic Geometry · Mathematics 2012-01-04 Yuji Odaka , Chenyang Xu

Shokurov conjectured that the set of all log canonical thresholds on varieties of bounded dimension satisfies the ascending chain condition. In this paper we prove that the conjecture holds for log canonical thresholds on smooth varieties…

Algebraic Geometry · Mathematics 2019-12-19 Tommaso de Fernex , Lawrence Ein , Mircea Mustata

We discuss the relationship among various conjectures in the minimal model theory including the finite generation conjecture of the log canonical rings and the abundance conjecture. In particular, we show that the finite generation…

Algebraic Geometry · Mathematics 2013-07-15 Osamu Fujino , Yoshinori Gongyo

We prove some injectivity, torsion-free, and vanishing theorems for simple normal crossing pairs. Our results heavily depend on the theory of mixed Hodge structures on compact support cohomology groups. We also treat several basic…

Algebraic Geometry · Mathematics 2013-01-25 Osamu Fujino

We consider pairs (X,A), where X is a variety with klt singularities and A is a formal product of ideals on X with exponents in a fixed set that satisfies the Descending Chain Condition. We also assume that X has (formally) bounded…

Algebraic Geometry · Mathematics 2010-06-25 Tommaso de Fernex , Lawrence Ein , Mircea Mustata

The main purpose of this paper is to establish some useful partial resolutions of singularities for pairs from the minimal model theoretic viewpoint. We first establish the existence of log canonical modifications of normal pairs under some…

Algebraic Geometry · Mathematics 2022-08-10 Osamu Fujino , Kenta Hashizume

Let T_n denote the set of log canonical thresholds of pairs (X,Y), with X a nonsingular variety of dimension n, and Y a nonempty closed subscheme of X. Using non-standard methods, we show that every limit of a decreasing sequence in T_n…

Algebraic Geometry · Mathematics 2009-02-02 Tommaso de Fernex , Mircea Mustata

The LCS locus is an essential ingredient in the proof of fundamental results of Log Minimal Model Program, such as nonvanishing and base point freeness theorems. We prove in this paper that the LCS locus of a log canonical variety has…

Algebraic Geometry · Mathematics 2007-05-23 Florin Ambro

We prove the Angehrn-Siu Type effective freeness and effective point separation for quasi-log canonical pairs. As a natural consequence, we obtain that these two results hold for semi-log canonical pairs. One of the main ingredients of our…

Algebraic Geometry · Mathematics 2019-07-17 Haidong Liu

1) Assuming log Minimal Model Conjecture, we give a construction of a complete moduli space of stable log pairs of arbitrary dimension generalizing directly the space M_{g,n} of pointed stable curves. Each stable pair has semi log canonical…

alg-geom · Mathematics 2008-02-03 Valery Alexeev

We introduce linearly decomposable (LD) generalized pairs, which serve as a workable substitute for rational decompositions in the non-NQC setting. Using LD generalized pairs, together with a refinement of special termination and…

Algebraic Geometry · Mathematics 2026-03-05 Zhengyu Hu , Jihao Liu

We prove a conjecture of Shokurov which characterises toric varieties using log pairs.

Algebraic Geometry · Mathematics 2018-05-23 Morgan Brown , James McKernan , Roberto Svaldi , Hong Zong