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Related papers: On threefold canonical thresholds

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In this paper the three-dimensional divisorial contractions $f\colon Y\to (X\ni P)$ are classified provided that $\Exc f=E$ is an irreducible divisor, $f(E)=P$, the variety $Y$ has canonical singularities and $(X\ni P)$ is a toric terminal…

Algebraic Geometry · Mathematics 2014-11-24 S. A. Kudryavtsev

A characterization of a class of optimal three-weight cyclic codes of dimension 3 over any finite field was recently presented in [10]. Shortly after this, a generalization for the sufficient numerical conditions of such characterization…

Information Theory · Computer Science 2016-09-26 Gerardo Vega

We study the problem of finding the largest number $T(n, m)$ of ternary vectors of length $n$ such that for any three distinct vectors there are at least $m$ coordinates where they pairwise differ. For $m = 1$, this is the classical…

This paper establishes quantitative correlation inequalities between monotone events and structured threshold objects in both the discrete cube and Gaussian space. We prove that for any increasing balanced family, there exists a linear…

Probability · Mathematics 2026-03-26 Yiming Chen , Guozheng Dai

We give the first elementary construction of equivalent formulas in Hanf normal form. The triply exponential upper bound is complemented by a matching lower bound.

Logic in Computer Science · Computer Science 2011-06-07 Benedikt Bollig , Dietrich Kuske

We prove that the lengths of extremal rays of log canonical Fano surfaces with Picard number one satisfy the ascending chain condition. This confirms the 2-dimensional case of a conjecture stated by Fujino and Ishitsuka

Algebraic Geometry · Mathematics 2014-10-27 Evgeny Mayanskiy

We prove the Nonvanishing Theorem for threefolds over an algebraically closed field $k$ of characteristic $p >5$.

Algebraic Geometry · Mathematics 2019-05-29 Chenyang Xu , Lei Zhang

Canonical framings and stable framings for the tangent bundle of a spin 3-manifold are introduced, and illustrated by a number of familiar examples. Methods for constructing canonical framings, and for comparing them with other naturally…

Geometric Topology · Mathematics 2007-05-23 Rob Kirby , Paul Melvin

We consider threefolds that admit a fibration by K3 surfaces over a nonsingular curve, equipped with a divisorial sheaf that defines a polarisation of degree two on the general fibre. Under certain assumptions on the threefold we show that…

Algebraic Geometry · Mathematics 2019-08-15 Alan Thompson

Let $\mathcal{T}$ be a finite nonempty set of $3$-element subsets of a totally ordered set $V$. We view $\mathcal{T}$ as the set of triangles in the support graph. Let $\delta_{1,\mathcal{T}}$ be the signed edge-triangle incidence matrix,…

Combinatorics · Mathematics 2026-05-27 Mutasim Mim

Let X be a smooth threefold. We show that if $X_i\dashrightarrow X_{i+1}$ is a flip which appears in the $K_X$-MMP, then $c_1(X_i)^3-c_1(X_{i+1})^3$ is bounded by a constant depending only on $b_2(X)$.

Algebraic Geometry · Mathematics 2024-11-12 Paolo Cascini , Hsin-Ku Chen

In recent decades, piecewise linear differential systems have attracted considerable attention due to their ability to describe a wide range of phenomena. A central problem, as in the theory of general planar differential systems, is to…

Dynamical Systems · Mathematics 2026-05-07 Sonia Isabel Renteria Alva , Pedro Iván Suárez Navarro

The process of alternately row scaling and column scaling a positive $n \times n$ matrix $A$ converges to a doubly stochastic positive $n \times n$ matrix $S(A)$, often called the \emph{Sinkhorn limit} of $A$. The main result in this paper…

Rings and Algebras · Mathematics 2019-10-01 Melvyn B. Nathanson

Let $(X,\mathcal{F})$ be a foliated surface over the complex numbers. We study the variation of $\epsilon$-adjoint singularities, defined by the adjoint divisor $K_{\mathcal{F}}+\epsilon K_X$ ($\epsilon>0$), and analyze their stability as…

Algebraic Geometry · Mathematics 2026-03-04 Shi Xu

It is shown that the log-canonical threshold of a curve with an isolated singularity is computed by the term ideal of the curve in a suitable system of local parameters at the singularity. The proof uses the Enriques diagram of the…

Algebraic Geometry · Mathematics 2007-07-06 Marian Aprodu , Daniel Naie

We prove that both classical Chevalley-Warning-Ax and Tsen theorems hold for the blowing up of a quintic 3-fold along a line of multiplicity 3. Both proofs, which are of the same spirit than the original ones, involve the description of…

Number Theory · Mathematics 2007-10-24 Marc Perret

The tiles of the canonical tilings (of the 3dimensional space) T*(2F) are six tetrahedra. We determine their inflation rules by the projection method.

Mathematical Physics · Physics 2007-05-23 Z. Papadopolos , C. Hohneker , P. Kramer

We prove the existence of two thresholds regarding the compilability of random 2-CNF formulas to OBDDs. The formulas are drawn from $\mathcal{F}_2(n,\delta n)$, the uniform distribution over all 2-CNFs with $\delta n$ clauses and $n$…

Data Structures and Algorithms · Computer Science 2026-05-20 Alexis de Colnet , Alfons Laarman , Joon Hyung Lee

We introduce a simple lattice model in which percolation is constructed on top of critical percolation clusters, and show that it can be repeated recursively any number $n$ of generations. In two dimensions, we determine the percolation…

Statistical Mechanics · Physics 2015-08-05 Youjin Deng , Jesper Lykke Jacobsen , Xuan-Wen Liu

We prove boundedness of rationally-connected threefolds in $\mathbb P^6$ under some extra-assumptions.

Algebraic Geometry · Mathematics 2014-07-25 Marian Aprodu , Matei Toma