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Related papers: Quasi-log varieties

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We prove that many of the results of the LMMP hold for $3$-folds over fields of characteristic $p>5$ which are not necessarily perfect. In particular, the existence of flips, the cone theorem, the contraction theorem for birational extremal…

Algebraic Geometry · Mathematics 2022-08-22 Omprokash Das , Joe Waldron

We prove that every quasi-log canonical pair has only Du Bois singularities. Note that our arguments are free from the minimal model program.

Algebraic Geometry · Mathematics 2023-02-14 Osamu Fujino , Haidong Liu

We give a light introduction to some recent developments in Mori theory, and to our recent direct proof of the finite generation of the canonical ring.

Algebraic Geometry · Mathematics 2019-04-15 Paolo Cascini , Vladimir Lazić

We show the existence of prime divisors computing minimal log discrepancies in positive characteristic except for a special case. Moreover we prove the lower semicontinuity of minimal log discrepancies for smooth varieties in positive…

Algebraic Geometry · Mathematics 2019-12-11 Kohsuke Shibata

We prove that the canonical ring of a smooth projective variety is finitely generated.

Algebraic Geometry · Mathematics 2008-08-14 Caucher Birkar , Paolo Cascini , Christopher D. Hacon , James McKernan

We prove the cone theorem for varieties with LCIQ singularities using deformation theory of stable maps into Deligne-Mumford stacks. We also obtain a sharper bound on $-(K_X+D)$-degree of $(K_X+D)$-negative extremal rays for projective…

Algebraic Geometry · Mathematics 2009-08-20 Jiun-Cheng Chen , Hsian-Hua Tseng

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

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

Let $X$ be a projective variety with log terminal singularities and vanishing augmented irregularity. In this paper we prove that if $X$ admits a relatively minimal genus one fibration then it does contain a subvariety of codimension one…

Algebraic Geometry · Mathematics 2019-03-14 Fabrizio Anella

We study (weak) log abelian varieties with constant degeneration in the log flat topology. If the base is a log point, we further study the endomorphism algebras of log abelian varieties. In particular, we prove the dual short exact…

Algebraic Geometry · Mathematics 2019-09-04 Heer Zhao

We generalize Miyanishi's theory of almost minimal models of log smooth surfaces with reduced boundary to the case of arbitrary log surfaces defined over an algebraically closed field. Given an MMP run of a log surface $(X,D)$ we define and…

Algebraic Geometry · Mathematics 2024-02-13 Karol Palka

We prove that every quasi-projective semi log canonical pair has a quasi-log structure with several good properties. It implies that various vanishing theorems, torsion-free theorem, and the cone and contraction theorem hold for semi log…

Algebraic Geometry · Mathematics 2013-10-29 Osamu Fujino

The main purpose of this notes is to supplement the paper reid, which treated Minimal Model Program (also called Mori's Program) on toric varieties. We calculate lengths of negative extremal rays of toric varieties. As an application, we…

Algebraic Geometry · Mathematics 2007-05-23 Osamu Fujino

We give canonical resolutions of singularities of several cone varieties arising from invariant theory. We establish a connection between our resolutions and resolutions of singularities of closure of conjugacy classes in classical Lie…

Algebraic Geometry · Mathematics 2007-05-23 Weiqiang Wang

We introduce a class of singular log schemes in three dimensions and conjecture that log schemes in this class admit log crepant log resolutions. We provide examples as evidence and relate this conjecture to the conjecture made in [4] and…

Algebraic Geometry · Mathematics 2025-03-17 Alessio Corti , Tim Graefnitz , Helge Ruddat

We discuss the cone theorem for quasi-log schemes and the Mori hyperbolicity. In particular, we establish that the log canonical divisor of a Mori hyperbolic projective normal pair is nef if it is nef when restricted to the non-lc locus.…

Algebraic Geometry · Mathematics 2022-12-27 Osamu Fujino

We list combinatorial criteria of some singularities, which appear in the Minimal Model Program or in the study of (singular) Fano varieties, for spherical varieties. Most of the results of this paper are already known or are quite easy…

Algebraic Geometry · Mathematics 2015-10-15 Boris Pasquier

We establish a kind of subadjunction formula for quasi-log canonical pairs. As an application, we prove that a connected projective quasi-log canonical pair whose quasi-log canonical class is anti-ample is simply connected and rationally…

Algebraic Geometry · Mathematics 2020-09-02 Osamu Fujino

We propose a subconjecture that implies the semiampleness conjecture for quasi-numerically positive log canonical divisors and prove the semiampleness in some elementary cases.

Algebraic Geometry · Mathematics 2015-11-11 Shigetaka Fukuda

In 2009, de Fernex and Hacon proposed a generalization of the notion of the singularities to normal varieties that are not Q-Gorenstein. Based on their work, we generalize Kleiman's transversality theorem to subvarieties with log terminal…

Algebraic Geometry · Mathematics 2011-11-21 Chih-Chi Chou