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We prove some results on the fibers and images of rational maps from a hyper-K\"ahler manifold. We study in particular the minimal genus of fibers of a fibration into curves. The last section of this paper is devoted to the study of the…

Algebraic Geometry · Mathematics 2022-08-23 Claire Voisin

Let $E\subseteq \mathbb{P}^2$ be a complex rational cuspidal curve contained in the projective plane and let $(X,D)\to (\mathbb{P}^2,E)$ be the minimal log resolution of singularities. Applying the log minimal model program to…

Algebraic Geometry · Mathematics 2019-04-30 Karol Palka

We classify the reflexive modules of rank one over rational and minimally elliptic singularities. Equivalently, we classify full line bundles on the resolutions of rational and minimally elliptic singularities. As an application, we…

Algebraic Geometry · Mathematics 2023-05-11 András Némethi , Agustín Romano-Velázquez

We define and study logics in the framework of probabilistic team semantics and over metafinite structures. Our work is paralleled by the recent development of novel axiomatizable and tractable logics in team semantics that are closed under…

Logic in Computer Science · Computer Science 2021-04-12 Miika Hannula , Minna Hirvonen , Juha Kontinen

We prove a structure theorem for non-isomorphic endomorphisms of weak Q-Fano threefolds, or more generally for threefolds with big anti-canonical divisor. Also provided is a criterion for a fibred rationally connected threefold to be…

Algebraic Geometry · Mathematics 2018-09-24 De-Qi Zhang

We prove that a Kawamata log terminal pair has the canonical model.

Algebraic Geometry · Mathematics 2020-04-09 Zhengyu Hu

We investigate mca-programs, that is, logic programs with clauses built of monotone cardinality atoms of the form kX, where k is a non-negative integer and X is a finite set of propositional atoms. We develop a theory of mca-programs. We…

Logic in Computer Science · Computer Science 2007-05-23 Victor W. Marek , Ilkka Niemela , Miroslaw Truszczynski

In this paper, we construct an analogy of holonomy of connection to simplicial sets using A-infinity-categories. To construct it, we develop fiberwise integrals on simplicial sets and define an iterated integral on simplicial sets. It is an…

Algebraic Topology · Mathematics 2022-11-15 Ryohei Kageyama

Let $(X,\Delta)$ be a log pair over $S$, such that $-(K_X+\Delta)$ is nef over $S$. It is conjectured that the intersection of the non-klt (non Kawamata log terminal) locus of $(X,\Delta)$ with any fiber $X_s$ has at most two connected…

Algebraic Geometry · Mathematics 2018-08-21 Christopher D. Hacon , Jingjun Han

In this new version, we add the proof of the main theorem when the central fiber is not necessarily simple normal crossing. We also correct some typos.

Algebraic Geometry · Mathematics 2013-06-17 Yuchen Liu

We establish a conjecture of Mumford characterizing rationally connected complex projective manifolds in several cases.

Algebraic Geometry · Mathematics 2017-05-05 Vladimir Lazić , Thomas Peternell

Complex reasoning over text requires understanding and chaining together free-form predicates and logical connectives. Prior work has largely tried to do this either symbolically or with black-box transformers. We present a middle ground…

Computation and Language · Computer Science 2021-06-08 Jiangming Liu , Matt Gardner , Shay B. Cohen , Mirella Lapata

In this work we propose a multi-valued extension of logic programs under the stable models semantics where each true atom in a model is associated with a set of justifications, in a similar spirit than a set of proof trees. The main…

Artificial Intelligence · Computer Science 2013-12-24 Pedro Cabalar , Jorge Fandinno

We extend the Cone Theorem of the Log Minimal Model Program to log varieties with arbitrary singularities.

Algebraic Geometry · Mathematics 2007-05-23 Florin Ambro

We prove basic statements about the Hermitian K-theory of exact form categories with weak equivalences. Notably, we extend a quadratic functor with values in abelian groups from an exact category to its category of bounded chain complexes…

K-Theory and Homology · Mathematics 2024-11-14 Marco Schlichting

We introduce an approach of Riemann--Roch theorem to the boundedness problem of minimal log discrepancies in fixed dimension. After reducing it to the case of a Gorenstein terminal singularity, firstly we prove that its minimal log…

Algebraic Geometry · Mathematics 2009-03-04 Masayuki Kawakita

We prove that the pull-back of a quasi-log scheme by a smooth quasi-projective morphism has a natural quasi-log structure. We treat an application to log Fano pairs. This paper also contains a proof of the simple connectedness of log Fano…

Algebraic Geometry · Mathematics 2016-06-21 Osamu Fujino

A result of Graber, Harris, and Starr shows that a rationally connected variety defined over the function field of a curve over the complex numbers always has a rational point. Similarly, a separably rationally connected variety over a…

Algebraic Geometry · Mathematics 2016-04-12 Bradley Duesler , Amanda Knecht

Under a slightly stronger hypothesis, one improves a connectedness result of Debarre [D] for a product of two projective spaces in terms of the extension problem of formal-rational functions (see Theorems 1.3 and 1.4 of the introduction)

Algebraic Geometry · Mathematics 2008-12-16 Lucian Bădescu

We establish extension theorems for separately holomorphic mappings defined on sets of the form W\setminus M with values in a complex analytic space which possesses the Hartogs extension property. Here W is a 2-fold cross of arbitrary…

Complex Variables · Mathematics 2009-01-21 Viet-Anh Nguyen , Peter Pflug