English
Related papers

Related papers: Excluded minors are almost fragile

200 papers

Spectrum of elementary string states in type II string theory contains ultra-short multiplets that are marginally stable. $U$-duality transformation converts these states into bound states at threshold of $p$-branes carrying Ramond-Ramond…

High Energy Physics - Theory · Physics 2009-09-15 Ashoke Sen

We prove a strong non-structure theorem for a class of metric structures with an unstable pair of formulae. As a consequence, we show that weak categoricity (that is, categoricity up to isomorphisms and not isometries) implies several…

Logic · Mathematics 2019-08-20 Saharon Shelah , Alexander Usvyatsov

We develop an abstract framework for studying the strong form of Malle's conjecture for nilpotent groups $G$ in their regular representation. This framework is then used to prove the strong form of Malle's conjecture for any nilpotent group…

Number Theory · Mathematics 2021-04-01 Peter Koymans , Carlo Pagano

We prove that for each finite field $\mathbb F$ and integer $k\in \mathbb Z$ there exists $n\in \mathbb Z$ such that no excluded minor for the class of $\mathbb F$-representable matroids has $n$ nested $k$-separations.

Combinatorics · Mathematics 2015-11-12 Shalev Ben-David , Jim Geelen

Let X be a normal complex algebraic variety, and p a prime. We show that there exists an integer N=N(X, p) such that: any non-trivial, irreducible representation of the fundamental group of X, which arises from geometry, must be non-trivial…

Algebraic Geometry · Mathematics 2016-12-22 Daniel Litt

Let $\Omega \subset \mathbb{R}^N$ ($N \geq 3$) be a bounded smooth domain and $\delta(x)=\text{dist}(x,\partial \Omega)$. In this paper, we provide various necessary and sufficient conditions for the existence of weak solutions to $$…

Analysis of PDEs · Mathematics 2018-07-16 Konstantinos T. Gkikas , Phuoc-Tai Nguyen

A nonlinear parabolic differential equation is presented which has at least one equilibrium. This equilibrium is shown to have a negative definite linearization, but a spectrum which includes zero. An elementary construction shows that the…

Analysis of PDEs · Mathematics 2007-05-23 Michael Robinson

Let $a$ and $b$ be elements in the closed ball of a unital C$^*$-algebra $A$ (if $A$ is not unital we consider its natural unitization). We shall say that $a$ and $b$ are domain (respectively, range) absolutely compatible ($a\triangle_d b$,…

Operator Algebras · Mathematics 2018-10-26 Nabin K. Jana , Anil K. Karn , Antonio M. Peralta

The paper considers the Schrodinger-Maxwell system with supercritical nonlinearitie. We prove the existence of at least one non-trivial weak solution. This result is already known for the subcritical case. In this paper, we extend it to the…

Analysis of PDEs · Mathematics 2018-08-28 Anouar Bahrouni

$(1)$ Let $M\subset N$ be a commutative cancellative torsion-free and subintegral extension of monoids. Then we prove that in the case of ring extension $A[M]\subset A[N]$, the two notions, subintegral and weakly subintegral coincide…

Commutative Algebra · Mathematics 2025-07-21 Md Abu Raihan , Leslie G. Roberts , Husney Parvez Sarwar

It is shown that the complex field equipped with the "approximate exponential map", defined up to ambiguity from a small group, is quasiminimal: every automorphism-invariant subset of the field is countable or co-countable. If the ambiguity…

Logic · Mathematics 2019-11-19 Jonathan Kirby

Let R be an associative ring with possible extra structure. R is said to be weakly small if there are countably many 1-types over any finite subset of R. It is locally P if the algebraic closure of any finite subset of R has property P. It…

Logic · Mathematics 2019-03-01 Cédric Milliet

We consider the problem of existence of constrained minimizers for the focusing mass-subcritical Half-Wave equation with a defocusing mass-subcritical perturbation. We show the existence of a critical mass such that minimizers do exist for…

Analysis of PDEs · Mathematics 2025-04-11 Jacopo Bellazzini , Luigi Forcella

We use a variation on Mason's $\alpha$-function as a pre-dimension function to construct a not one-based $\omega$-stable plane $P$ (i.e. a simple rank $3$ matroid) which does not admit an algebraic representation (in the sense of matroid…

Logic · Mathematics 2020-01-13 Gianluca Paolini

Let $M$ be a matroid. We study the expansions of $M$ mainly to see how the combinatorial properties of $M$ and its expansions are related to each other. It is shown that $M$ is a graphic, binary or a transversal matroid if and only if an…

Combinatorics · Mathematics 2017-05-29 Rahim Rahmati-Asghar

Let M be a hyperbolizable, nontrivial compression body without toroidal boundary components. In this paper, we characterize which discrete and faithful representations of the fundamental group of M into PSL(2,C) are separable-stable. The…

Geometric Topology · Mathematics 2013-11-07 Inkang Kim , Michelle Lee

This technical report accompanies the following three papers. It contains the computations necessary to verify some of the results claimed in those papers. [1] Carolyn Chun, Deborah Chun, Dillon Mayhew, and Stefan H. M. van Zwam.…

Combinatorics · Mathematics 2015-11-12 Carolyn Chun , Deborah Chun , Benjamin Clark , Dillon Mayhew , Geoff Whittle , Stefan H. M. van Zwam

Regular groups and fields are common generalizations of minimal and quasi-minimal groups and fields, so the conjectures that minimal or quasi-minimal fields are algebraically closed have their common generalization to the conjecture that…

Logic · Mathematics 2012-11-19 Tomasz Gogacz , Krzysztof Krupinski

We give a constructive proof of the factorization theorem for the classical Hardy space in terms of fractional integral operator. Moreover, the result is extended to the multilinear case and weighted case. As an application, we obtain the…

Functional Analysis · Mathematics 2021-12-14 Dinghuai Wang , Rongxiang Zhu

We show that if $2k\geq n$, then a k-connected weak n-category $A$ can be ``delooped'' to a k+1-connected weak n+1-category $Y$ with $Hom_Y(y,y)\cong A$. This is the essential part of the ``stabilization hypothesis'' of Baez and Dolan…

Category Theory · Mathematics 2007-05-23 Carlos Simpson