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Related papers: On divisors computing MLD's and LCT's

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We give asymptotic estimates for the mean number of divisors of integers without small prime factors, integers with bounded ratios of consecutive divisors, and for practical numbers. In the last case, this confirms a conjecture of…

Number Theory · Mathematics 2023-06-28 Andreas Weingartner

We prove that the moduli b-divisor of an lc-trivial fibration from a log canonical pair is log abundant. The result follows from a theorem on the restriction of the moduli b-divisor, based on a theory of lc-trivial morphisms, which allows…

Algebraic Geometry · Mathematics 2021-02-16 Zhengyu Hu

We show that log canonical thresholds of fixed dimension are standardized. More precisely, we show that any sequence of log canonical thresholds in fixed dimension $d$ accumulates in a way which is i) either similar to how standard and…

Algebraic Geometry · Mathematics 2024-06-07 Jihao Liu , Fanjun Meng , Lingyao Xie

The log canonical threshold (lct) is a fundamental invariant in birational geometry, essential for understanding the complexity of singularities in algebraic varieties. Its real counterpart, the real log canonical threshold (rlct), also…

Algebraic Geometry · Mathematics 2026-01-15 Dimitra Kosta , Daniel Windisch

In this paper, we study the singularities of a pair (X,Y) in arbitrary characteristic via jet schemes. For a smooth variety X in characteristic 0, Ein, Lazarsfeld and Mustata showed that there is a correspondence between irreducible closed…

Algebraic Geometry · Mathematics 2013-08-27 Zhixian Zhu

Inside the symmetric product of a very general curve, we consider the codimension-one subvarieties of symmetric tuples of points imposing exceptional secant conditions on linear series on the curve of fixed degree and dimension. We compute…

Algebraic Geometry · Mathematics 2016-02-03 Nicola Tarasca

Under the assumption of the minimal model theory for projective klt pairs of dimension $n$, we establish the minimal model theory for lc pairs $(X/Z,\Delta)$ such that the log canonical divisor is relatively log abundant and its restriction…

Algebraic Geometry · Mathematics 2019-08-29 Kenta Hashizume , Zhengyu Hu

Iannucci considered the positive divisors of a natural number $n$ that do not exceed the square root of $n$ and found all numbers whose such divisors are in arithmetic progression. Continuing the work, we define large divisors to be…

Number Theory · Mathematics 2019-12-30 Hung Viet Chu

In this note, we extend work of Farkas and Rim\'anyi on applying quadric rank loci to finding divisors of small slope on the moduli space of curves by instead considering all divisorial conditions on the hypersurfaces of a fixed degree…

Algebraic Geometry · Mathematics 2021-10-06 Dennis Tseng

We prove that if Y is a hypersurface of degree d in P^n with isolated singularities, then the log canonical threshold of (P^n,Y) is at least min{n/d,1}. Moreover, if d is at least n+1, then we have equality if and only if Y is the…

Algebraic Geometry · Mathematics 2007-05-23 Lawrence Ein , Mircea Mustata

Building on results of Koll\'ar, we prove Shokurov's ACC Conjecture for log canonical thresholds on smooth varieties, and more generally, on varieties with quotient singularities.

Algebraic Geometry · Mathematics 2009-01-09 Lawrence Ein , Mircea Mustata

We prove that the first gap of $\mathbb R$-complementary thresholds of surfaces is $\frac{1}{13}$. More precisely, the largest $\mathbb R$-complementary threshold for surfaces that is strictly less than $1$ is $\frac{12}{13}$. This result…

Algebraic Geometry · Mathematics 2023-05-31 Jihao Liu , V. V. Shokurov

Let $X$ be a smooth hypersurface of degree $n\geq 3$ in $\mathbb{P}^n$. We prove that the log canonical threshold of $H\in|-K_X|$ is at least $\frac{n-1}{n}$. Under the assumption of the Log minimal model program, we also prove that a…

Algebraic Geometry · Mathematics 2007-05-23 Ivan Cheltsov , Jihun Park

We give a classification of the dual graphs of the exceptional divisors on the minimal resolutions of log canonical foliation singularities on surfaces. For an application, we show the set of foliated minimal log discrepancies for foliated…

Algebraic Geometry · Mathematics 2021-04-02 Yen-An Chen

A determination of the fixed components, base points and irregularity is made for arbitrary numerically effective divisors on any smooth projective rational surface having an effective anticanonical divisor. All of the results are proven…

alg-geom · Mathematics 2009-09-25 Brian Harbourne

An integer $n$ is called practical if every $m\le n$ can be written as a sum of distinct divisors of $n$. We show that the number of practical numbers below $x$ is asymptotic to $c x/\log x$, as conjectured by Margenstern. We also give an…

Number Theory · Mathematics 2015-03-04 Andreas Weingartner

The log canonical thresholds of irreducible quasi-ordinary hypersurface singularities are computed, using an explicit list of pole candidates for the motivic zeta function found by the last two authors.

Algebraic Geometry · Mathematics 2011-05-16 Nero Budur , Pedro D. González-Pérez , Manuel González Villa

We study lower bounds for the self-intersection of the canonical divisor of "canonical varieties" (i.e. varieties whose canonical linear system gives a birational map). We give some improvements for the known results in the case of surfaces…

Algebraic Geometry · Mathematics 2007-05-23 Miguel A. Barja

Minimal log discrepancies (mld's) are related not only to termination of log flips, and thus to the existence of log flips but also to the ascending chain condition (acc) of some global invariants and invariants of singularities in the Log…

Algebraic Geometry · Mathematics 2007-05-23 Caucher Birkar , V. V. Shokurov

In this article, we will characterize the multiplier ideal sheaves with weights of log canonical threshold one by restricting the weights to complex regular surface.

Complex Variables · Mathematics 2016-04-13 Qi'an Guan , Zhenqian Li