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Related papers: Separating properties for normal ultrafilters

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We introduce the decomposability spectrum $K_D=\{\lambda \geq \omega| D \text{is} \lambda\text{-decomposable}\}$ of an ultrafilter $D$, and show that Shelah's $\pcf$ theory influences the possible values $K_D$ can take. For example, we show…

Logic · Mathematics 2007-05-23 Paolo Lipparini

In standard construction of hyperrational numbers using an ultrapower we assume that the ultrafilter is selective. It makes possible to assign real value to any finite hyperrational number. So, we can consider hyperrational numbers with…

Logic · Mathematics 2020-04-06 Armen Grigoryants

Circular-harmonic spectra are a compact representation of local image features in two dimensions. It is well known that the computational complexity of such transforms is greatly reduced when polar separability is exploited in steerable…

Computer Vision and Pattern Recognition · Computer Science 2020-11-09 Hugh L Kennedy

We prove that under H\"ormander's type conditions on the coefficients of the unobservable component of a partially observable diffusion process the filtering density is infinitely differentiable and can be represented as the integral of an…

Probability · Mathematics 2013-09-24 N. V. Krylov

Uniformly star superparacompactness, which is a topological property between compactness and completeness, can be characterized using finite-component covers and a measure of strong local compactness. Using these finite-component covers and…

General Topology · Mathematics 2025-05-02 Argha Ghosh

Singular spectrum analysis is developed as a nonparametric spectral decomposition of a time series. It can be easily extended to the decomposition of multidimensional lattice-like data through the filtering interpretation. In this…

Computer Vision and Pattern Recognition · Computer Science 2015-05-08 Kenji Kume , Naoko Nose-Togawa

In literature, many important combinatorial properties of subsets of N have been studied both with nonstandard techniques and from the point of view of N. In this thesis we mix these two different approaches in a technique that, at the same…

Logic · Mathematics 2012-12-11 Lorenzo Luperi Baglini

If $\mathcal P$ is a family of filters over some set $I$, a topological space $X$ is \emph{sequencewise $\mathcal P$-\brfrt compact} if, for every $I$-indexed sequence of elements of $X$, there is $F \in \mathcal P$ such that the sequence…

General Topology · Mathematics 2016-08-30 Paolo Lipparini

We study partition properties for uncountable regular cardinals that arise by restricting partition properties defining large cardinal notions to classes of simply definable colourings. We show that both large cardinal assumptions and…

Logic · Mathematics 2018-07-03 Philipp Lücke

For a free ultrafilter U on omega we study several cardinal characteristics which describe part of the combinatorial structure of U. We provide various consistency results; e.g. we show how to force simultaneously many characters and many…

Logic · Mathematics 2016-09-07 Jörg Brendle , Saharon Shelah

We generalize the results from "P. Lipparini, Productive $[\lambda,\mu]$-compactness and regular ultrafilters, Topology Proceedings, 21 (1996), 161--171"; in particular the present results apply to singular cardinals, too.

General Topology · Mathematics 2008-04-24 Paolo Lipparini

Matrices are built and designed by applying procedures from lower order matrices. Matrix tensor products, direct sums or multiplication of matrices are such procedures and a matrix built from these is said to be a {\em separable} matrix. A…

Rings and Algebras · Mathematics 2024-03-07 Ted Hurley , Barry Hurley

We derive and study a significance test for determining if a panel of functional time series is separable. In the context of this paper, separability means that the covariance structure factors into the product of two functions, one…

Statistics Theory · Mathematics 2018-01-18 Panayiotis Constantinou , Piotr Kokoszka , Matthew Reimherr

The so-called permutation separability criteria are simple operational conditions that are necessary for separability of mixed states of multipartite systems: (1) permute the indices of the density matrix and (2) check if the trace norm of…

Quantum Physics · Physics 2007-05-23 Pawel Wocjan , Michal Horodecki

The primary goal of this paper is to establish a model of $ZFC$ wherein the definable tree property is affirmed for all uncountable regular cardinals. This endeavor commences with the utilization of both a supercompact cardinal and a…

Logic · Mathematics 2023-10-10 Mohammad Golshani , Mostafa Mirabi

In Euclidean spaces, every closed, bounded, convex set can be characterized by two equivalent notions of separation properties. This is not true in general for arbitrary Banach spaces. In this work, we present a ball separation…

Functional Analysis · Mathematics 2025-11-12 Sudeshna Basu , Susmita Seal

In this paper we show that in systems where the probability distribution of the the overlap is non trivial in the infinity volume limit, the property of ultrametricity can be proved in general starting from two very simple and natural…

Disordered Systems and Neural Networks · Physics 2009-10-31 Giorgio Parisi , Federico Ricci-Tersenghi

We provide examples of nonseparable compact spaces with the property that any continuous image which is homeomorphic to a finite product of spaces has a maximal prescribed number of nonseparable factors.

General Topology · Mathematics 2014-09-15 Antonio Avilés

We show the consistency of the set of regular cardinals which are the character of some ultrafilter on omega is not convex. We also deal with the set of pi chi-characters of ultrafilters on omega.

Logic · Mathematics 2007-08-15 Saharon Shelah

In a typical two-slits experiments we face the question whether it is possible or not to attain knowledge about properties incompatible with Which-Slit property together with the measurement of the final impact point. A wide family of…

Quantum Physics · Physics 2008-08-21 Angela Sestito