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Related papers: Mld's vs thresholds and flips

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We systematically introduce and study a new type of singularities, namely, exceptionally non-canonical (enc) singularities. This class of singularities plays an important role in the study of many questions in birational geometry, and has…

Algebraic Geometry · Mathematics 2025-01-29 Jingjun Han , Jihao 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 $(X, \mcF, \D)$ is a projective rank two foliated log canonical triple such that $(X,B)$ is klt for some $0 \leq B \leq \D$, we show that we can run a $(K_\mcF +\Delta)$-MMP and any such MMP terminates with either a minimal model or Mori…

Algebraic Geometry · Mathematics 2025-12-23 Priyankur Chaudhuri , Roktim Mascharak

We show that the minimal log discrepancy of any isolated Fano cone singularity is at most the dimension of the variety. This is based on its relation with dimensions of moduli spaces of orbifold rational curves. We also propose a…

Algebraic Geometry · Mathematics 2025-02-18 Chi Li , Zhengyi Zhou

In this article we prove the existence of pl-flipping and divisorial contractions and pl flips in dimension $n$ for compact K\"ahler varieties, assuming results of the minimal model program in dimension $n-1$. We also give a self contained…

Algebraic Geometry · Mathematics 2024-06-27 Omprokash Das , Christopher Hacon

The first aim of this note is to give a concise, but complete and self-contained, presentation of the fundamental theorems of Mori theory - the nonvanishing, base point free, rationality and cone theorems - using modern methods of…

Algebraic Geometry · Mathematics 2014-02-26 Alessio Corti , Anne-Sophie Kaloghiros , Vladimir Lazic

We survey some recent topics on singularities, with a focus on their connection to the minimal model program. This includes the construction and properties of dual complexes, the proof of the ACC conjecture for log canonical thresholds and…

Algebraic Geometry · Mathematics 2017-12-05 Chenyang Xu

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 prove the existence of flips for $\mathbb Q$-factorial NQC generalized lc pairs, and the cone and contraction theorems for NQC generalized lc pairs. This answers a question of C. Birkar which was conjectured by J. Han and Z. Li. As an…

Algebraic Geometry · Mathematics 2021-09-10 Christopher D. Hacon , Jihao Liu

We introduce linearly decomposable (LD) generalized pairs, which serve as a workable substitute for rational decompositions in the non-NQC setting. Using LD generalized pairs, together with a refinement of special termination and…

Algebraic Geometry · Mathematics 2026-03-05 Zhengyu Hu , Jihao Liu

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

We survey the known and expected properties of the minimal log discrepancy, the local invariant of a log variety.

Algebraic Geometry · Mathematics 2007-05-23 Florin Ambro

We show the existence of prime divisors computing minimal log discrepancies in positive characteristic except for a special case. Moreover we prove the lower semicontinuity of minimal log discrepancies for smooth varieties in positive…

Algebraic Geometry · Mathematics 2019-12-11 Kohsuke Shibata

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

We compute the minimal log discrepancies of determinantal varieties of square matrices, and more generally of pairs $\bigl(D^k,\sum \alpha_i D^{k_i}\bigr)$ consisting of a determinantal variety (of square matrices) and an $\mathbb R$-linear…

Algebraic Geometry · Mathematics 2019-06-14 Devlin Mallory

Shokurov's ACC Conjecture says that the set of all log canonical thresholds on varieties of bounded dimension satisfies the Ascending Chain Condition. This conjecture was proved for log canonical thresholds on smooth varieties in [EM1].…

Algebraic Geometry · Mathematics 2009-01-09 Tommaso de Fernex , Mircea Mustata

We will prove the following results for $3$-fold pairs $(X,B)$ over an algebraically closed field $k$ of characteristic $p>5$: log flips exist for $\Q$-factorial dlt pairs $(X,B)$; log minimal models exist for projective klt pairs $(X,B)$…

Algebraic Geometry · Mathematics 2014-10-17 Caucher Birkar

This paper characterizes singularities with Mather minimal log discrepancies in the highest unit interval, i.e., the interval between $d-1$ and $d$, where $d$ is the dimension of the scheme. The class of these singularities coincides with…

Algebraic Geometry · Mathematics 2013-04-29 Shihoko Ishii , Ana Reguera

The second largest accumulation point of the set of minimal log discrepancies of threefolds is $\frac{5}{6}$. In particular, the minimal log discrepancies of $\frac{5}{6}$-lc threefolds satisfy the ACC.

Algebraic Geometry · Mathematics 2022-07-12 Jihao Liu , Yujie Luo

We prove the existence of pl-flips.

Algebraic Geometry · Mathematics 2008-08-15 Christopher D. Hacon , James McKernan