English
Related papers

Related papers: New Expander Bounds from Affine Group Energy

200 papers

In 2022, using methods from ergodic theory, Kra, Moreira, Richter, and Robertson resolved a longstanding conjecture of Erd\H{o}s about sumsets in large subsets of the natural numbers. In this paper, we extend this result to several…

Dynamical Systems · Mathematics 2025-01-29 Dimitrios Charamaras , Andreas Mountakis

A theory of dispersionless Andreev bound states on surfaces of time-reversal invariant unconventional superconductors is presented. The generalized criterion for the dispersionless Andreev bound state is derived from the bulk-edge…

Superconductivity · Physics 2015-03-18 Masatoshi Sato , Yukio Tanaka , Keiji Yada , Takehito Yokoyama

We establish the boundedness of weak subsolutions for a class of degenerate Kolmogorov equations of hypoelliptic type, compatible with a homogeneous Lie group structure, within bounded product domains using the De Giorgi iteration. We…

Analysis of PDEs · Mathematics 2025-02-21 Mingyi Hou

We examine the spectrum and boundary energy in boundary sine-Gordon theory, based on our recent results on the complete spectrum predicted by closing the boundary bootstrap. We check the spectrum and the reflection factors against truncated…

High Energy Physics - Theory · Physics 2009-11-07 Z. Bajnok , L. Palla , G. Takacs

For an input graph $G$, an additive spanner is a sparse subgraph $H$ whose shortest paths match those of $G$ up to small additive error. We prove two new lower bounds in the area of additive spanners: 1) We construct $n$-node graphs $G$ for…

Data Structures and Algorithms · Computer Science 2022-10-07 Greg Bodwin , Gary Hoppenworth

We study truncation compatible families F = (F_m)_{m>=1} over Q[z] through an inverse limit formalism, and we evaluate them at the punctured cyclotomic cosine points alpha_{k,n} = cos(2 pi k/n) with the specialization z equals n-1. For…

Combinatorics · Mathematics 2026-02-10 Juan D. Velez , Carlos Cadavid

Naslund used Tao's slice rank bounding method to give new exponential upper bounds for the Erd\H{o}s--Ginzburg-Ziv constant of finite Abelian groups of high rank. In our short manuscript we improve slightly Naslund's upper bounds. We extend…

Number Theory · Mathematics 2017-12-04 Gábor Hegedüs

Residual finiteness growth gives an invariant that indicates how well-approximated a finitely generated group is by its finite quotients. We briefly survey the state of the subject. We then improve on the best known upper and lower bounds…

Group Theory · Mathematics 2019-09-17 Khalid Bou-Rabee , Junjie Chen , Anastasiia Timashova

We prove the following conjecture of Shkredov and Solymosi: every subset $A \subset \mathbf{Z}^2$ such that $\sum_{a\in A\setminus\{0\}} 1/\left\|a\right\|^{2} = +\infty$ contains the three vertices of an isosceles right triangle. To do…

Combinatorics · Mathematics 2022-12-02 Cédric Pilatte

We develop a theory of additive group actions on affine ind-schemes through a purely algebraic and topological framework. Affine ind-schemes are described via complete, second-countable, linearly topologized rings, and actions of the…

Commutative Algebra · Mathematics 2026-01-29 Roberto Diaz , Adrien Dubouloz , Alvaro Liendo

In this paper, we introduce a new function related to the sum of element orders of finite groups. It is used to give some criteria for a finite group to be cyclic, abelian, nilpotent, supersolvable and solvable, respectively.

Group Theory · Mathematics 2019-04-09 Marius Tărnăuceanu

We establish improved finite field Szemeredi-Trotter and Beck type theorems. First we show that if P and L are a set of points and lines respectively in the plane F_p^2, with |P|,|L| \leq N and N<p, then there are at most C_1…

Combinatorics · Mathematics 2012-06-21 Timothy G. F. Jones

We study the boundary of an affine invariant submanifold of a stratum of translation surfaces in a partial compactification consisting of all finite area Abelian differentials over nodal Riemann surfaces, modulo zero area components. The…

Dynamical Systems · Mathematics 2020-07-15 Maryam Mirzakhani , Alex Wright

We use recent results about linking the number of zeros on algebraic varieties over $\mathbb{C}$, defined by polynomials with integer coefficients, and on their reductions modulo sufficiently large primes to study congruences with products…

Number Theory · Mathematics 2022-07-25 Bryce Kerr , Jorge Mello , Igor Shparlinski

In this paper we introduce a unified approach to deal with incidence problems between points and varieties over finite fields. More precisely, we prove that the number of incidences $I(\mathcal{P}, \mathcal{V})$ between a set $\mathcal{P}$…

Combinatorics · Mathematics 2016-01-05 Nguyen Duy Phuong , Thang Pham , Nguyen Minh Sang , Claudiu Valculescu , Le Anh Vinh

Given a subset of real numbers $A$ with small product $AA$ we obtain a new upper bound for the additive energy of $A$. The proof uses a natural observation that level sets of convolutions of the characteristic function of $A$ have small…

Combinatorics · Mathematics 2019-11-28 Konstantin I. Olmezov , Aliaksei S. Semchankau , Ilya D. Shkredov

We show that countable increasing unions preserve a large family of well-studied covering properties, which are not necessarily sigma-additive. Using this, together with infinite-combinatorial methods and simple forcing theoretic methods,…

General Topology · Mathematics 2018-04-06 Tal Orenshtein , Boaz Tsaban

We prove a new weak mean ergodic theorem (Theorem A) for 1-cocycles associated to weakly mixing representations of amenable groups. Let $G$ be a finitely generated, discrete, amenable group $G$ which admits a controlled Folner sequence. We…

Group Theory · Mathematics 2012-08-06 Ionut Chifan , Thomas Sinclair

We generalize the Szemer\'edi-Trotter incidence theorem, to bound the number of complete \emph{flags} in higher dimensions. Specifically, for each $i=0,1,\ldots,d-1$, we are given a finite set $S_i$ of $i$-flats in $\R^d$ or in $\C^d$, and…

Combinatorics · Mathematics 2015-12-31 Saarik Kalia , Micha Sharir , Noam Solomon , Ben Yang

We prove a strong general-purpose bound for the diameter of a finite group depending only on the diameters of its composition factors and the maximal exponent of a normal abelian section. There are a number of notable applications: (1) if…

Group Theory · Mathematics 2026-04-21 Sean Eberhard , Elena Maini , Luca Sabatini , Gareth Tracey