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Related papers: Failures of weak approximation in families

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This paper explores the well known approximation approach to decide weak bisimilarity of Basic Parallel Processes. We look into how different refinement functions can be used to prove weak bisimilarity decidable for certain subclasses. We…

Formal Languages and Automata Theory · Computer Science 2012-08-15 Piotr Hofman , Patrick Totzke

We introduce the weak Haagerup property for locally compact groups and prove several hereditary results for the class of groups with this approximation property. The class contains a priori all weakly amenable groups and groups with the…

Operator Algebras · Mathematics 2016-09-19 Søren Knudby

We propose a family of variational approximations to Bayesian posterior distributions, called $\alpha$-VB, with provable statistical guarantees. The standard variational approximation is a special case of $\alpha$-VB with $\alpha=1$. When…

Statistics Theory · Mathematics 2018-02-09 Yun Yang , Debdeep Pati , Anirban Bhattacharya

Given a finite extension $K/k$ of number fields and a smooth quasi-projective variety $X$ over $K$. If the abelianized fundamental group of $X$ is trivial, we prove that there is a natural identification between Brauer-Manin sets of $X$ and…

Number Theory · Mathematics 2026-04-14 Sheng Chen , Kai Huang

We consider a class of nearest-neighbor weakly asymmetric mass conservative particle systems evolving on $\mathbb{Z}$, which includes zero-range and types of exclusion processes, starting from a perturbation of a stationary state. When the…

Probability · Mathematics 2016-08-14 Patrícia Gonçalves , Milton Jara , Sunder Sethuraman

A set family ${\cal F}$ is $uncrossable$ if $A \cap B,A \cup B \in {\cal F}$ or $A \setminus B,B \setminus A \in {\cal F}$ for any $A,B \in {\cal F}$. A classic result of Williamson, Goemans, Mihail, and Vazirani [STOC 1993:708-717] states…

Data Structures and Algorithms · Computer Science 2023-07-21 Zeev Nutov

In this paper, we study the existence of the random approximations and fixed points for random almost lower semicontinuous operators defined on finite dimensional Banach spaces, which in addition, are condensing or 1-set-contractive. Our…

Probability · Mathematics 2015-07-13 Monica Patriche

We consider a generalisation of the Seiberg-Witten invariant to the families Seiberg-Witten invariants of a smooth family of 4-manifolds with fibres diffeomorphic to a 4-manifold $X$. Of particular interest is the special case when the…

Algebraic Geometry · Mathematics 2022-08-19 Joshua Celeste

This article develops general conditions for weak convergence of adaptive Markov chain Monte Carlo processes and is shown to imply a weak law of large numbers for bounded Lipschitz continuous functions. This allows an estimation theory for…

Statistics Theory · Mathematics 2026-01-14 Austin Brown , Jeffrey S. Rosenthal

In this article, we establish the arithmetic purity of strong approximation for smooth loci of weighted projective spaces. By using this result and the descent method, we also prove that the arithmetic purity of strong approximation with…

Algebraic Geometry · Mathematics 2022-07-20 Sheng Chen

Let $k$ be a number field, let $X$ be a Kummer variety over $k$, and let $\delta$ be an odd integer. In the spirit of a result by Yongqi Liang, we relate the arithmetic of rational points over finite extensions of $k$ to that of zero-cycles…

Number Theory · Mathematics 2018-10-16 Francesca Balestrieri , Rachel Newton

An approximation scheme is a family of homogeneous subsets $(A_n)$ of a quasi-Banach space $X$, such that $A_1 \subsetneq A_2 \subsetneq ... \subsetneq X$, $A_n + A_n \subset A_{K(n)}$, and $\bar{\cup_n A_n} = X$. Continuing the line of…

Classical Analysis and ODEs · Mathematics 2010-10-26 J. M. Almira , T. Oikhberg

We define a weak compatibility condition for the Newest Vertex Bisection algorithm on simplex grids of any dimension and show that using this condition the iterative algorithm terminates successfully. Additionally we provide an O(n)…

Numerical Analysis · Mathematics 2017-11-10 Martin Alkämper , Fernando Gaspoz , Robert Klöfkorn

We give an example of a vector bundle E on a relative curve C --> Spec Z such that the restriction to the generic fiber in characteristic zero is semistable but such that the restriction to positive characteristic p is not strongly…

Number Theory · Mathematics 2007-05-23 Holger Brenner

The problem of approximating a dense matrix by a product of sparse factors is a fundamental problem for many signal processing and machine learning tasks. It can be decomposed into two subproblems: finding the position of the non-zero…

Computational Complexity · Computer Science 2022-11-23 Quoc-Tung Le , Elisa Riccietti , Rémi Gribonval

In this paper, we discuss the theory of quasi-fibrations in proper Bousfield localizations of model categories of simplicial sheaves. We provide a construction of fibrewise localization and use this construction to generalize a criterion…

Algebraic Topology · Mathematics 2014-10-01 Matthias Wendt

Using full images of accessible functors, we prove some results about combinatorial and accessible model categories. In particular, we give an example of a weak factorization system on a locally presentable category which is not accessible.

Category Theory · Mathematics 2022-02-08 Jiří Rosický

Variational Inference makes a trade-off between the capacity of the variational family and the tractability of finding an approximate posterior distribution. Instead, Boosting Variational Inference allows practitioners to obtain…

Machine Learning · Computer Science 2021-05-20 Gideon Dresdner , Saurav Shekhar , Fabian Pedregosa , Francesco Locatello , Gunnar Rätsch

We prove $f$-positivity of $\mathcal{O}_X(1)$ for arbitrary dimension fibrations over curves $f\colon X\to B$ whose general fibre is a complete intersection. In the special case where the family is a global complete intersection, we prove…

Algebraic Geometry · Mathematics 2023-12-29 Miguel Angel Barja , Lidia Stoppino

For locally convex spaces, we systematize several known equivalent definitions of Fr\'echet (G\^ ateaux) Differentiability Spaces and Asplund (Weak Asplund) Spaces. As an application, we extend the classical Mazur's theorem as follows: Let…

Functional Analysis · Mathematics 2024-12-16 Jerzy Kakol , Arkady Leiderman