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Related papers: Potential log canonical centers

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We establish adjunction and inversion of adjunction for log canonical centers of arbitrary codimension in full generality.

Algebraic Geometry · Mathematics 2022-08-17 Osamu Fujino , Kenta Hashizume

Let $(X, \Delta)$ be a klt threefold pair with nef anti-log canonical bundle $-(K_X+\Delta)$. We show that $\kappa(X, -(K_X+\Delta))\geq 0$. To do so, we prove a more general equivariant non-vanishing result for anti-log canonical bundles,…

Algebraic Geometry · Mathematics 2025-08-13 Niklas Müller

We prove the finiteness of log pluricanonical representations for projective log canonical pairs with semi-ample log canonical divisor. As a corollary, we obtain that the log canonical divisor of a projective semi log canonical pair is…

Algebraic Geometry · Mathematics 2012-04-10 Osamu Fujino , Yoshinori Gongyo

We introduce the class of weakly log canonical singularities, a natural generalization of semi-log canonical singularities. Toric varieties (associated to toric face rings, possibly non-normal or reducible) which have weakly (semi-) log…

Algebraic Geometry · Mathematics 2017-11-02 Florin Ambro

We give a criterion for a divisorial sheaf on a log terminal variety to be Cohen-Macaulay. The log canonical case and applications to moduli are also considered.

Algebraic Geometry · Mathematics 2010-05-27 János Kollár

We extend a subadjunction formula of log canonical divisors as in [K3] to the case when the codimension of the minimal center is arbitrary by using the positivity of the Hodge bundles.

alg-geom · Mathematics 2007-05-23 Yujiro Kawamata

In this paper, we completely work out the log minimal model program for the moduli space of stable curves of genus three. We employ a rational multiple $\alpha\delta$ of the divisor $\delta$ of singular curves as the boundary divisor,…

Algebraic Geometry · Mathematics 2007-05-23 Donghoon Hyeon , Yongnam Lee

In this paper we provide asymptotic upper bounds on the complexity in two (closely related) situations. We confirm for the total doubling coverings and not only for the chains the expected bounds of the form $$ \kappa({\mathcal U}) \le…

Classical Analysis and ODEs · Mathematics 2019-03-12 Raf Cluckers , Omer Friedland , Yosef Yomdin

In this paper, we generalize the finiteness of models theorem in [BCHM06] to Kawamata log terminal pairs with fixed Kodaira dimension. As a consequence, we prove that a Kawamata log terminal pair with $\mathbb{R}-$boundary has a canonical…

Algebraic Geometry · Mathematics 2020-05-08 Junpeng Jiao

We prove that the log canonical ring of a klt pair of dimension $3$ with $\mathbb{Q}$-boundary over an algebraically closed field of characteristic $p>5$ is finitely generated. In the process we prove log abundance for such pairs in the…

Algebraic Geometry · Mathematics 2016-05-02 Joe Waldron

For a toric log variety with standard coefficients, we show that the minimal log discrepancy at a closed invariant point bounds the Cartier index of a neighbourhood.

Algebraic Geometry · Mathematics 2008-11-18 Florin Ambro

Given a Fano type log Calabi-Yau fibration $(X,B)\to Z$ with $(X,B)$ being $\epsilon$-lc, the first author in \cite{Bi23} proved that the generalised pair $(Z,B_Z+M_Z)$ given by the canonical bundle formula is generalised $\delta$-lc where…

Algebraic Geometry · Mathematics 2024-12-13 Caucher Birkar , Bingyi Chen

We introduce a mixed characteristic analog of log canonical centers in characteristic $0$ and centers of $F$-purity in positive characteristic, which we call centers of perfectoid purity. We show that their existence detects (the failure…

Algebraic Geometry · Mathematics 2025-09-17 Anne Fayolle

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

Let X be a smooth variety over a field of positive characteristic, and let E be an overconvergent isocrystal on X. We establish a criterion for the existence of a "canonical logarithmic extension" of E to a good compactification of X. In…

Number Theory · Mathematics 2007-05-23 Kiran S. Kedlaya

We obtain condition for existence of a center for a cubic planar differential system, which can be considered as a polynomial subfamily of the generalized Riccati system. We also investigate bifurcations of small limit cycles from the…

Dynamical Systems · Mathematics 2017-06-02 Zhengxin Zhou , Valery G. Romanovski , Jiang Yu

Let $X$ be a quotient of a bounded domain in $\mathbb C^n$. Under suitable assumptions, we prove that every subvariety of $X$ not included in the branch locus of the quotient map is of log general type in some orbifold sense. This…

Algebraic Geometry · Mathematics 2022-07-28 Benoît Cadorel , Simone Diverio , Henri Guenancia

We prove that if X is a locally complete intersection variety, then X has all the jet schemes irreducible if and only if X has canonical singularities. After embedding X in a smooth variety Y, we use motivic integration to express the…

Algebraic Geometry · Mathematics 2009-10-31 Mircea Mustata

For a variety $X$, a big $\mathbb{Q}$-divisor $L$ and a closed connected subgroup $G \subset \mathrm{Aut}(X, L)$ we define a $G$-invariant version of the $\delta$-threshold. We prove that for a Fano variety $(X, -K_X)$ and a connected…

Algebraic Geometry · Mathematics 2020-08-27 Aleksei Golota

Given a graded sequence of ideals (a_m) on a smooth variety $X$ having finite log canonical threshold, suppose that for every m we have a divisor E_m over X that computes the log canonical threshold of a_m, and such that the log…

Algebraic Geometry · Mathematics 2011-07-05 Mattias Jonsson , Mircea Mustata