English
Related papers

Related papers: A local Ramsey theory for block sequences

200 papers

We show that the Ramsey theory of block sequences in infinite-dimensional discrete vector spaces can be parametrized by perfect sets. As special cases, we prove combinatorial dichotomies for definable families of partitions and linear…

Combinatorics · Mathematics 2026-05-15 Iian B. Smythe

We study families of infinite block sequences of elements of the space $\FIN_k$. In particular we study Ramsey properties of such families and Ramsey properties localized to a selective or semiselective coideal. We show how the stable…

Combinatorics · Mathematics 2026-04-30 Daniel Calderon , Carlos Di Prisco , Jose G. Mijares

We extend the well known notion of \textit{coideal} on $\mathbb{N}$ to families of block sequences on $FIN_k$ and prove that if a coideal of block sequences is \textit{semiselective} and satisfies a local version of Gowers' theorem…

Combinatorics · Mathematics 2010-08-31 José G. Mijares , Jesús Nieto

A well-known application of the Ramsey Theorem in the Banach Space Theory is the proof of the fact that every normalized basic sequence has a subsequence which generates a spreading model (the Brunel-Sucheston Theorem). Based on this…

Functional Analysis · Mathematics 2020-09-08 S. Garcia-Ferreira , A. C. Hernandez-Soto

We show that Ramsey theory, a domain presently conceived to guarantee the existence of large homogeneous sets for partitions on k-tuples of words (for every natural number k) over a finite alphabet, can be extended to one for partitions on…

Combinatorics · Mathematics 2007-05-23 V. Farmaki , S. Negrepontis

We prove an exact, i.e., formulated without $\Delta$-expansions, Ramsey principle for infinite block sequences in vector spaces over countable fields, where the two sides of the dichotomic principle are represented by respectively winning…

Functional Analysis · Mathematics 2008-07-15 Christian Rosendal

Given a topological Ramsey space $(\mathcal R,\leq, r)$, we extend the notion of semiselective coideal to sets $\mathcal H\subseteq\mathcal R$ and study conditions for $\mathcal H$ that will enable us to make the structure $(\mathcal…

Logic · Mathematics 2015-07-07 Carlos Di Prisco , Jose G. Mijares , Jesus Nieto

We develop a general framework for infinite-dimensional Ramsey theory with and without pigeonhole principle, inspired by Gowers' Ramsey-type theorem for block sequences in Banach spaces and by its exact version proved by Rosendal. In this…

Logic · Mathematics 2020-01-22 Noé de Rancourt

It is shown that the known notion of selective coideal can be extended to a family $\mathcal{H}$ of subsets of $\mathcal{R}$, where $(\mathcal{R},\leq,r)$ is a topological Ramsey space in the sense of Todorcevic (see \cite{todo}). Then it…

Logic · Mathematics 2007-12-17 José Mijares , Jesús Nieto

We prove a Ramsey theorem for finite sets equipped with a partial order and a fixed number of linear orders extending the partial order. This is a common generalization of two recent Ramsey theorems due to Soki\'c. As a bonus, our proof…

Combinatorics · Mathematics 2015-02-17 Slawomir Solecki , Min Zhao

In Banach space theory, the ``local theory'' refers to the collection of finite dimensional methods and ideas which are used to study infinite dimensional spaces (see e.g. [P4,TJ]). It is natural to try to develop an analogous theory in the…

Functional Analysis · Mathematics 2009-09-25 Gilles Pisier

In this paper we extend the block combinatorics partition theorems of Hindman and Milliken in the setting of the recursive system of the block Schreier families (B^xi) consisting of families defined for every countable ordinal xi. Results…

Combinatorics · Mathematics 2007-05-23 V. Farmaki , S. Negrepontis

We prove that for any homogeneous structure $\mathbf{K}$ in a language with finitely many relation symbols of arity at most two satisfying SDAP$^+$ (or LSDAP$^+$), there are spaces of subcopies of $\mathbf{K}$, forming subspaces of the…

Logic · Mathematics 2023-02-23 Natasha Dobrinen

We extend Pisier's abstract version of Grothendieck's theorem to general non-locally convex quasi-Banach spaces. We also prove a related result on factoring operators through a Banach space and apply our results to the study of…

Functional Analysis · Mathematics 2008-02-03 Nigel J. Kalton , Sik-Chung Tam

We prove the Ramsey property for classes of ordered structures with closures and given local properties. This generalises earlier results: the Ne\v{s}et\v{r}il-R\"odl Theorem, the Ramsey property of partial orders and metric spaces as well…

Combinatorics · Mathematics 2019-09-04 Jan Hubička , Jaroslav Nešetřil

In this paper, an algebraic theory for local rings of finite embedding dimension is developed. Several extensions of (Krull) dimension are proposed, which are then used to generalize singularity notions from commutative algebra. Finally,…

Commutative Algebra · Mathematics 2014-08-27 Hans Schoutens

We prove some results on the border of Ramsey theory (finite partition calculus) and model theory. Also a beginning of classification theory of finite models in undertaken.

Logic · Mathematics 2016-09-06 Doug Ensley , Rami Grossberg

A problem of Banach asks whether every infinite-dimensional Banach space which is isomorphic to all its infinite-dimensional subspaces must be isomorphic to a separable Hilbert space. In this paper we prove a result of a Ramsey-theoretic…

Functional Analysis · Mathematics 2007-05-23 W. T. Gowers

In this paper, we establish a local limit theorem for linear fields of random variables constructed from independent and identically distributed innovations each with finite second moment. When the coefficients are absolutely summable we do…

Probability · Mathematics 2020-08-06 Timothy Fortune , Magda Peligrad , Hailin Sang

We prove various results in infinite-dimensional differential calculus which relate differentiability properties of functions and associated operator-valued functions (e.g., differentials). The results are applied in two areas: 1. in the…

Functional Analysis · Mathematics 2022-03-04 Helge Glockner
‹ Prev 1 2 3 10 Next ›