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We present an approach over arbitrary fields to bound the degree of intersection of families of varieties in terms of how these concentrate on algebraic sets of smaller codimension. This provides in particular a substantial extension of the…

Algebraic Geometry · Mathematics 2019-12-30 Miguel N. Walsh

In this paper, we find some new sharp bounds for $\left(\sin x\right) /x$, which unify and refine Jordan, Adamovi\'{c}-Mitrinovi\'{c}and and Cusa's inequalities. As applications of main results, some new Shafer-Fink type inequalities for…

Classical Analysis and ODEs · Mathematics 2013-04-12 Zhen-Hang Yang

We present methods for bounding infinite-time averages in dynamical systems governed by nonlinear PDEs. The methods rely on auxiliary functionals, which are similar to Lyapunov functionals but satisfy different inequalities. The…

Dynamical Systems · Mathematics 2020-04-16 David Goluskin , Giovanni Fantuzzi

We reconsider the Gram-Hadamard bound as it is used in constructive quantum field theory and many body physics to prove convergence of Fermionic perturbative expansions. Our approach uses a recursion for the amplitudes of the expansion,…

Mathematical Physics · Physics 2016-05-25 Martin Lohmann

This paper develops an optimal Chernoff type bound for the probabilities of large deviations of sums $\sum_{k=1}^n f (X_k)$ where $f$ is a real-valued function and $(X_k)_{k \in \mathbb{Z}_{\ge 0}}$ is a finite state Markov chain with an…

Probability · Mathematics 2019-12-24 Vrettos Moulos , Venkat Anantharam

We consider the problem of bounding the number of exceptional projections (projections which are smaller than typical) of a subset of a vector space over a finite field onto subspaces. We establish bounds that depend on $L^p$ estimates for…

Combinatorics · Mathematics 2025-04-24 Jonathan M. Fraser , Firdavs Rakhmonov

Bounds on the log partition function are important in a variety of contexts, including approximate inference, model fitting, decision theory, and large deviations analysis. We introduce a new class of upper bounds on the log partition…

Machine Learning · Computer Science 2013-01-07 Martin Wainwright , Tommi S. Jaakkola , Alan Willsky

We establish a polynomial ergodic theorem for actions of the affine group of a countable field $K$. As an application, we deduce--via a variant of Furstenberg's correspondence principle--that for fields of characteristic zero, any "large"…

Combinatorics · Mathematics 2026-01-14 Ioannis Kousek

Using some new observations connected to higher energies, we obtain quantitative lower bounds on $\max\{|AB|, |A+C| \}$ and $\max\{|(A+\alpha)B|, |A+C|\}$, $\alpha \neq 0$ in the regime when the sizes of finite subsets $A,B,C$ of a field…

Number Theory · Mathematics 2018-08-22 Ilya D. Shkredov

We extend a bound of Roche-Newton, Shparlinski and Winterhof which says any subset of a finite field can be decomposed into two disjoint subset $\cU$ and $\cV$ of which the additive energy of $\cU$ and $f(\cV)$ are small, for suitably…

Number Theory · Mathematics 2018-03-30 Simon Macourt

In this paper, we prove a new point-sphere incidence bound in vector spaces over finite fields. More precisely, let $P$ be a set of points and $S$ be a set of spheres in $\mathbb{F}_q^d$. Suppose that $|P|, |S|\le N$, we prove that the…

Combinatorics · Mathematics 2021-09-20 Doowon Koh , Thang Pham

In this paper, we study unique, globally defined uniformly bounded weak solutions for a class of semilinear reaction-diffusion-advection systems. The coefficients of the differential operators and the initial data are only required to be…

Analysis of PDEs · Mathematics 2021-09-10 William E Fitzgibbon , Jeff Morgan , Bao Quoc Tang , Hong-Ming Yin

The formation of bound states at surfaces of materials with an energy gap in the bulk electron spectrum is a well known physical phenomenon. At superconductor surfaces, quasiparticles with energies inside the superconducting gap $\Delta$…

Superconductivity · Physics 2009-11-07 T. Lofwander , V. S. Shumeiko , G. Wendin

It is shown that it is possible to establish sum rules that must be satisfied at the nodes and extrema of the eigenstates of confining potentials which are functions of a single variable. At any boundstate energy the Schroedinger equation…

Quantum Physics · Physics 2009-11-13 C. V. Sukumar

We show that an infinite residually finite boundedly generated group has an infinite chain of finite index subgroups with ranks uniformly bounded, and give (sublinear) upper bounds on the ranks of arbitrary finite index subgroups of…

Group Theory · Mathematics 2017-05-04 Mark Shusterman

We consider the system of 3 nonrelativistic spinless fermions in two dimensions, which interact through spherically-symmetric pair interactions. Recently a claim has been made for the existence of the so-called super Efimov effect [Y.…

Mathematical Physics · Physics 2014-11-27 Dmitry K. Gridnev

Let $(G,+)$ be a countable abelian group such that the subgroup $\{g+g\colon g\in G\}$ has finite index and the doubling map $g\mapsto g+g$ has finite kernel. We establish lower bounds on the upper density of a set $A\subset G$ with respect…

Dynamical Systems · Mathematics 2025-04-14 Dimitrios Charamaras , Ioannis Kousek , Andreas Mountakis , Tristán Radić

We give new upper bounds for the diameters of finite groups which do not depend on a choice of generating set. Our method exploits the commutator structure of certain profinite groups, in a fashion analogous to the Solovay-Kitaev procedure…

Group Theory · Mathematics 2014-10-14 Henry Bradford

The purpose of this paper is to revisit the proof of the Gearhardt-Pr\"uss-Hwang-Greiner theorem for a semigroup $S(t)$, following the general idea of the proofs that we have seen in the literature and to get an explicit estimate on $\Vert…

Optimization and Control · Mathematics 2021-03-12 Bernard Helffer , Johannes Sjöstrand

As a generalisation of Graham and Lehrer's cellular algebras, affine cellular algebras have been introduced in [12] in order to treat affine versions of diagram algebras like affine Hecke algebras of type A and affine Temperley-Lieb…

Representation Theory · Mathematics 2017-12-05 Paula A. A. B. Carvalho , Steffen Koenig , Christian Lomp , Armin Shalile