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Related papers: The locus of log canonical singularities

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Let T_n denote the set of log canonical thresholds of pairs (X,Y), with X a nonsingular variety of dimension n, and Y a nonempty closed subscheme of X. Using non-standard methods, we show that every limit of a decreasing sequence in T_n…

Algebraic Geometry · Mathematics 2009-02-02 Tommaso de Fernex , Mircea Mustata

We show that any union of slc strata of a Fano log pair with semi-log canonical singularities is simply connected. In particular, Fano log pairs with semi-log canonical singularities are simply connected, which confirms a conjecture of the…

Algebraic Geometry · Mathematics 2017-12-12 Osamu Fujino , Wenfei Liu

We study a pair consisting of a smooth variety over a field of positive characteristic and a multi-ideal with a real exponent. We prove the finiteness of the set of minimal log discrepancies for a fixed exponent if the dimension is less…

Algebraic Geometry · Mathematics 2025-09-12 Shihoko Ishii

If the log canonical divisor on a projective variety with only Kawamata log terminal singularities is numerically equivalent to some semi-ample $\mathbf{Q}$-divisor, then it is semi-ample.

Algebraic Geometry · Mathematics 2011-11-07 Shigetaka Fukuda

We prove that the target space of an extremal Fano contraction from a log canonical pair has only log canonical singularities. We also treat some related topics, for example, the finite generation of canonical rings for compact K\"ahler…

Algebraic Geometry · Mathematics 2014-06-26 Osamu Fujino

It is known that the set of log canonical thresholds (lcts) on any varieties with fixed dimension satisfies the ascending chain condition. Inspired by the foliated minimal model program, it is intriguing to study the foliated version of…

Algebraic Geometry · Mathematics 2025-11-13 Yen-An Chen

We generalize the rationality theorem of the accumulation points of log canonical thresholds which was proved by Hacon, M\textsuperscript{c}Kernan, and Xu. Further, we apply the rationality to the ACC problem on the minimal log…

Algebraic Geometry · Mathematics 2024-04-30 Yusuke Nakamura

On smooth threefolds, the ACC for minimal log discrepancies is equivalent to the boundedness of the log discrepancy of some divisor which computes the minimal log discrepancy. We reduce it to the case when the boundary is the product of a…

Algebraic Geometry · Mathematics 2018-03-08 Masayuki Kawakita

Motivated by Shokurov's ACC Conjecture for log canonical thresholds, we propose an inductive point of view on singularities of pairs, in the case when the ambient variety is smooth. Our main result characterizes the log canonicity of a pair…

Algebraic Geometry · Mathematics 2010-04-23 Mircea Mustata

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

In this paper a description of the small-$\hbar$ limit of loci of zeros of fundamental solutions for polynomial potentials is given. The considered cases of the potentials are bounded to the ones which provided us with simple turning points…

Mathematical Physics · Physics 2008-12-16 Stefan Giller

We define the "source" and the "spring" of a log canonical center and use them to solve several problems in higher-codimension adjunction. The main application is to the construction of semi log canonical pairs. Version 2: References…

Algebraic Geometry · Mathematics 2012-11-15 János Kollár

We prove Koll\'ar-type effective basepoint-free theorems for quasi-log canonical pairs.

Algebraic Geometry · Mathematics 2016-11-24 Osamu Fujino

Let $(X,B)$ be a projective log canonical pair such that $B$ is a $\Q$-divisor, and that there is a surjective morphism $f\colon X\to Z$ onto a normal variety $Z$ satisfying: $K_X+B\sim_\Q f^*M$ for some $\Q$-divisor $M$, and the augmented…

Algebraic Geometry · Mathematics 2019-02-20 Caucher Birkar , Zhengyu Hu

Let $(P\in X,\Delta)$ be a three dimensional log canonical pair such that $\Delta$ has only standard coefficients and $P$ is a center of log canonical singularities for $(X,\Delta)$. Then we get an effective bound of the indices of these…

Algebraic Geometry · Mathematics 2007-05-23 Osamu Fujino

We establish a relative spannedness for log canonical pairs, which is a generalization of the basepoint-freeness for varieties with log-terminal singularities by Andreatta--Wi\'sniewski. Moreover, we establish a generalization for quasi-log…

Algebraic Geometry · Mathematics 2020-12-01 Osamu Fujino

We show that the log canonical threshold polytopes of varieties with log canonical singularities satisfy the ascending chain condition.

Algebraic Geometry · Mathematics 2020-11-05 Jingjun Han , Zhan Li , Lu Qi

We show that the family of semi log canonical pairs with ample log canonical class and with fixed volume is bounded.

Algebraic Geometry · Mathematics 2017-09-22 Christopher Hacon , James McKernan , Chenyang Xu

We study further Mumford's notion of local semistability and, in particular, show that semistable singularities are log canonical under mild assumptions. We provide many new examples of semistable and unstable singularities. More generally,…

Algebraic Geometry · Mathematics 2025-09-30 Linquan Ma , Ilya Smirnov

We prove the abundance theorem for log canonical $n$-folds such that the boundary divisor is big assuming the abundance conjecture for log canonical $(n-1)$-folds. We also discuss the log minimal model program for log canonical $4$-folds.

Algebraic Geometry · Mathematics 2015-11-04 Kenta Hashizume