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Related papers: Abundance for slc surfaces over arbitrary fields

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This work consists of two parts. In the first part we develop new techniques to compute Koszul cohomology groups for several classes of varieties. As applications we prove results on projective normality and syzygies for algebraic surfaces.…

alg-geom · Mathematics 2008-02-03 F. J. Gallego , B. P. Purnaprajna

We prove the finiteness of $B$-representations of generalised log canonical pairs. As a consequence, we prove that, the (relative) abundance for a generalised semi-log canonical pair is implied by the abundance for its normalisation.…

Algebraic Geometry · Mathematics 2021-03-23 Zhengyu Hu

The purpose of this note is to give a new proof of Alexeev's boundedness result for stable surfaces which is independent of the base field and to highlight some important consequences of this result.

Algebraic Geometry · Mathematics 2016-10-04 Christopher D. Hacon , Sándor J Kovács

We study the normalizations of non-normal stable families of slc surfaces over an excellent DVR. In mixed characteristic, we establish a gluing statement that is relevant for the properness of the moduli space of such surfaces. We also…

Algebraic Geometry · Mathematics 2024-01-09 Quentin Posva

We prove the finiteness of relative log pluricanonical representations in the complex analytic setting. As an application, we discuss the abundance conjecture for semi-log canonical pairs within this framework. Furthermore, we establish the…

Algebraic Geometry · Mathematics 2025-06-03 Osamu Fujino

In this paper, we prove the non-vanishing and some special cases of the abundance for log canonical threefold pairs over an algebraically closed field $k$ of characteristic $p > 3$. More precisely, we prove that if $(X,B)$ be a projective…

Algebraic Geometry · Mathematics 2024-02-06 Zheng Xu

We give a new proof of the finiteness of B-representations. As a consequence of the finiteness of B-representations and Koll\'ar's gluing theory on lc centers, we prove that the (relative) abundance conjecture for slc pairs is implied by…

Algebraic Geometry · Mathematics 2012-05-23 Christopher Hacon , Chenyang Xu

We discuss the relative log minimal model theory for log surfaces in the analytic setting. More precisely, we show that the minimal model program, the abundance theorem, and the finite generation of log canonical rings hold for log pairs of…

Algebraic Geometry · Mathematics 2026-04-15 Nao Moriyama

In this paper, we prove abundance for non-uniruled 3-folds with non-trivial Albanese maps, over an algebraically closed field of characteristic $p > 5$. As an application we get a characterization of abelian 3-folds.

Algebraic Geometry · Mathematics 2018-09-26 Lei Zhang

We prove that the abundance conjecture holds on a variety $X$ with mild singularities if $X$ has many reflexive differential forms with coefficients in pluricanonical bundles, assuming the Minimal Model Program in lower dimensions. This…

Algebraic Geometry · Mathematics 2025-08-22 Vladimir Lazić , Thomas Peternell

We show that a weak version of the canonical bundle formula holds for fibrations of relative dimension one. We provide various applications thereof, for instance, using the recent result of Xu and Zhang, we prove the log non-vanishing…

Algebraic Geometry · Mathematics 2018-04-11 Jakub Witaszek

We give an analytic version of the injectivity theorem by using multiplier ideal sheaves, and prove some extension theorems for the adjoint bundle of dlt pairs. Moreover, by combining techniques of the minimal model program, we obtain some…

Algebraic Geometry · Mathematics 2014-07-30 Yoshinori Gongyo , Shin-ichi Matsumura

We prove Iitaka's $C_{n,m}$ conjecture for $3$-folds over the algebraic closure of finite fields. Along the way we prove some results on the birational geometry of log surfaces over nonclosed fields and apply these to existence of relative…

Algebraic Geometry · Mathematics 2015-09-01 Caucher Birkar , Yifei Chen , Lei Zhang

We give combinatorial formulas for the Laurent expansion of any cluster variable in any cluster algebra coming from a triangulated surface (with or without punctures), with respect to an arbitrary seed. Moreover, we work in the generality…

Combinatorics · Mathematics 2009-06-04 Gregg Musiker , Ralf Schiffler , Lauren Williams

We prove that the abundance conjecture for non-uniruled klt pairs in dimension $n$ implies the abundance conjecture for uniruled klt pairs in dimension $n$, assuming the Minimal Model Program in lower dimensions.

Algebraic Geometry · Mathematics 2015-09-15 Tobias Dorsch , Vladimir Lazić

We consider the Zariski-Lipman Conjecture on free module of derivations for algebraic surfaces. Using the theory of non-complete algebraic surfaces, and some basic results about ruled surfaces, we will prove the conjecture for several…

Algebraic Geometry · Mathematics 2014-03-25 Indranil Biswas , R. V. Gurjar , Sagar U. Kolte

We establish a near dichotomy between randomness and structure for the point counts of arbitrary projective cubic threefolds over finite fields. Certain "special" subvarieties, not unlike those in the Manin conjectures, dominate. We also…

Number Theory · Mathematics 2023-04-25 Victor Y. Wang

We prove that there are at most 13 real quadratic fields that admit a ternary universal quadratic lattice, thus establishing a strong version of Kitaoka's Conjecture for quadratic fields. More generally, we obtain explicit upper bounds on…

Number Theory · Mathematics 2025-02-03 Vitezslav Kala , Jakub Krásenský , Dayoon Park , Pavlo Yatsyna , Błażej Żmija

In the previous article, we showed the Rasmussen-Tamagawa conjecture for QM-abelian surfaces over imaginary quadratic fields. In this article, we generalize the previous work to QM-abelian surfaces over number fields of higher degree. We…

Number Theory · Mathematics 2013-01-01 Keisuke Arai

We prove Reider type criterions for k-jet spannedness and k-jet ampleness of adjoint bundles for surfaces with at most rational singularities. Moreover, we prove that on smooth surfaces [n(n+4)/4]-very ampleness implies n-jet ampleness.

Algebraic Geometry · Mathematics 2007-05-23 Adrian Langer