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Related papers: On quasi-log schemes

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We introduce various new operations for quasi-log structures. Then we prove the basepoint-free theorem of Reid--Fukuda type for quasi-log schemes as an application.

Algebraic Geometry · Mathematics 2015-07-21 Osamu Fujino

This paper is a gentle introduction to the theory of quasi-log varieties by Ambro. We explain the fundamental theorems for the log minimal model program for log canonical pairs. More precisely, we give a proof of the base point free theorem…

Algebraic Geometry · Mathematics 2009-10-25 Osamu Fujino

The hypoplactic monoid was introduced by Krob and Thibon through a presentation and through quasi-ribbon tableaux and an insertion algorithm. Just as Kashiwara crystals enriched the structure of the plactic monoid and allowed its…

Combinatorics · Mathematics 2023-01-03 Alan J. Cain , Ricardo P. Guilherme , António Malheiro

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

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

A quasi-schemoid is a small category whose morphisms are colored with appropriate combinatorial data. In this note, Mitchell's embedding theorem for a tame schemoid is established. The result allows us to give a cofibrantly generated model…

Category Theory · Mathematics 2016-02-29 Katsuhiko Kuribayashi , Yasuhiro Momose

A quasi-order is a binary, reflexive and transitive relation. In the Journal of Pure and Applied Algebra 45 (1987), S.M. Fakhruddin introduced the notion of (totally) quasi-ordered fields and showed that each such field is either an ordered…

Commutative Algebra · Mathematics 2018-07-18 Simon Müller

Kawamata has shown that the quasi-Albanese map of a quasi-projective variety with log-irregularity equal to the dimension and log-Kodaira dimension 0 is birational. In this note we show that under these hypotheses the quasi-Albanese map is…

Algebraic Geometry · Mathematics 2024-01-22 Margarida Mendes Lopes , Rita Pardini , Sofia Tirabassi

In this paper, we give a criterion for the existence of logarithmic embeddings -- which was first introduced by Steenbrink -- for general normal crossing varieties. Using this criterion, we also give a new proof of the theorem of…

alg-geom · Mathematics 2008-02-03 Fumiharu Kato

Let F be the free group over a set of two or more generators. R. Brooks constructed an infinite family of quasi-morphisms on F such that an infinite subfamily gives rise to independent classes in the second bounded cohomology of F, which…

Group Theory · Mathematics 2009-11-24 Pascal Rolli

In this paper, we show that Fujita's basepoint-freeness conjecture for projective quasi-log canonical singularities holds true in dimension three. Immediately, we prove Fujita-type basepoint-freeness for projective semi-log canonical…

Algebraic Geometry · Mathematics 2019-02-25 Haidong Liu

We discuss Iitaka's theory of quasi-Albanese maps in details. We also give a detailed proof of Kawamata's theorem on the quasi-Albanese maps for varieties of the logarithmic Kodaira dimension zero. Note that Iitaka's theory is an…

Algebraic Geometry · Mathematics 2024-03-22 Osamu Fujino

This article begins with an exploration of nonlinear codes ($\mathbb{F}_q$-linear subspaces of $\mathbb{F}_{q^m}^n$) which are generalizations of the familiar Reed-Solomon codes. This then leads to a wider exploration of nonlinear analogues…

Information Theory · Computer Science 2025-02-12 Daniel Bossaller , Daniel Herden , Indalecio Ruiz-Bolanos

The concept of quantum Fermi liquid for description of (quasi)-1D electronic systems is recovered. The model of (quasi)-1D quantum Fermi liquid is developed on the example of trans-polyacetylene and it is the generalization of well-known…

Strongly Correlated Electrons · Physics 2013-08-09 Alla Dovlatova , Dmitri Yerchuck , Felix Borovik

Link spectral invariants were introduced by Cristofaro-Gardiner, Humili\`ere, Mak, Seyfaddini, and Smith. They induce Hofer-Lipschitz quasimorphisms on the group of Hamiltonian diffeomorphisms of the two-dimensional sphere. We prove that…

Symplectic Geometry · Mathematics 2025-09-19 Baptiste Serraille , Ibrahim Trifa

Quasi-logarithmic combinatorial structures are a class of decomposable combinatorial structures which extend the logarithmic class considered by Arratia, Barbour and Tavar\'{e} (2003). In order to obtain asymptotic approximations to their…

Combinatorics · Mathematics 2010-07-30 A. D. Barbour , Bruno Nietlispach

In this paper we re-examine the theory of systems with quasi-discrete spectrum initiated in the 1960's by Abramov, Hahn, and Parry. In the first part, we give a simpler proof of the Hahn--Parry theorem stating that each minimal topological…

Dynamical Systems · Mathematics 2017-06-02 Markus Haase , Nikita Moriakov

We apply the technique of quasi-adiabatic continuation to study systems with continuous symmetries. We first derive a general form of Goldstone's theorem applicable to gapped nonrelativistic systems with continuous symmetries. We then show…

Statistical Mechanics · Physics 2009-11-11 M. B. Hastings

The recently developed theory of quasi-Lie schemes is studied and applied to investigate several equations of Emden type and a scheme to deal with them and some of their generalisations is given. As a first result we obtain t-dependent…

Mathematical Physics · Physics 2009-10-03 J. F. Cariñena , P. G. L. Leach , J. de Lucas

Let $(X, \Delta)$ be a four-dimensional log variety that is projective over the field of complex numbers. Assume that $(X, \Delta)$ is not Kawamata log terminal (klt) but divisorial log terminal (dlt). First we introduce the notion of "log…

Algebraic Geometry · Mathematics 2007-05-23 Shigetaka Fukuda
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