English
Related papers

Related papers: A Universal Continuum of Weight aleph

200 papers

We introduce notions of absolutely continuous functionals and representations on the non-commutative disk algebra $A_n$. Absolutely continuous functionals are used to help identify the type L part of the free semigroup algebra associated to…

Operator Algebras · Mathematics 2007-05-23 Kenneth R. Davidson , Jiankui Li , David R. Pitts

We establish a general criterion on the upper semi-continuity of partial entropy in all directions for $C^{1+\alpha}$ diffeomorphisms: it holds when the respective sums of Lyapunov exponents are continuous. This addresses, in arbitrary…

Dynamical Systems · Mathematics 2026-05-14 Gang Liao , Huirong Tao , Yao Tong , Jiagang Yang

We prove that if less than $\aleph_{\omega}$-many Cohen reals are added to a model of \textsf{CH}, then $\omega^{\ast}$ can not be covered by nowhere dense \textsf{P}-sets (equivalently, there is an ultrafilter on $\omega$ that does not…

Logic · Mathematics 2025-09-18 Alan Dow , Osvaldo Guzmán

A set X which is a subset of the Cantor set has property (s) (Marczewski (Spzilrajn)) iff for every perfect set P there exists a perfect set Q contained in P such that Q is a subset of X or Q is disjoint from X. Suppose U is a nonprincipal…

Logic · Mathematics 2007-05-23 Arnold W. Miller

In this paper it will be shown that assuming the Continuum Hypothesis (CH) every nonreflexive Banach space ultrapower is isometrically isomorphic to the space of continuous, bounded and real-valued functions on the Parovicenko space. This…

Logic · Mathematics 2011-07-11 Piotr Wilczek

We characterize those complete commutative positive linear ordered monoids $W$ such that whenever $f$ is a map from a Cauchy complete $W$-metric space to itself, the existence of a fixed point of $f$ is independent of the background model…

General Topology · Mathematics 2025-04-15 Nathanael Ackerman , Mostafa Mirabi

We state a new generic absoluteness principle, and use Shelah's memory iteration technique to show that it is consistent with the large continuum.

Logic · Mathematics 2023-10-10 Mohammad Golshani

We prove that for $\mathcal{C}^{1,\alpha}$ diffeomorphisms on a compact manifold $M$ with ${\rm dim} M\leq 3$, if an invariant measure $\mu$ is a continuity point of the sum of positive Lyapunov exponents, then $\mu$ is an upper…

Dynamical Systems · Mathematics 2025-04-15 Chiyi Luo , Dawei Yang

Let $M$ be a closed smooth manifold and let $f:M\to M$ be a diffeomorphism. $C^1$-generically, a continuum-wise expansive satisfies Axiom A without cycles. Moreover, there is a partially hyperbolic diffeomorphism $f$ such that it is not…

Dynamical Systems · Mathematics 2016-03-08 Manseob Lee

In 2014, we determine the precise form of a continuous orthogonal form on a commutative real C$^*$-algebra. We also describe the general form of a (not-necessarily continuous) orthogonality preserving linear map between commutative unital…

Operator Algebras · Mathematics 2015-11-30 Antonio M. Peralta

Assuming the continuum hypothesis there is an inseparable sequence of length omega_1 that contains no Lusin subsequence, while if Martin's Axiom and the negation of CH is assumed then every inseparable sequence (of length omega_1) is a…

Logic · Mathematics 2009-09-25 Uri Abraham , Saharon Shelah

Starting from the $\rm{GCH},$ we build a cardinal and $\rm{GCH}$ preserving generic extension of the universe, in which there exists a set $A \subseteq \omega_2$ of size $\aleph_2$ so that every countably infinite subset of $A$ or $\omega_2…

Logic · Mathematics 2023-08-25 Esfandiar Eslami , Mohammad Golshani , Rouholah Hoseini Naveh

We prove that there exists a nonprincipal ultrafilter $\mathcal U$ on $\mathbb N$ such that for every countable (or separable) structure $B$ in a countable language the quotient map from the reduced product associated with the Fr\'echet…

Logic · Mathematics 2021-04-20 Ilijas Farah

We introduce and study the notion of entropy of affine permutations and prove that it coincides with the atomic length associated with the sum of the fundamental weights for a type $A$ affine root system, as defined by the first two…

Representation Theory · Mathematics 2026-03-24 Nathan Chapelier-Laget , Thomas Gerber , Nicolas Jacon , Cédric Lecouvey

In this note, as a particular case of a more general result, we obtain the following theorem: Let $\Omega\subseteq {\bf R}^n$ be a non-empty bounded open set and let $f:\overline {\Omega}\to {\bf R}^n$ be a continuous function which is…

Analysis of PDEs · Mathematics 2016-02-17 Biagio Ricceri

In [FHK13], the authors considered the question whether model-existence of $L_{\omega_1,\omega}$-sentences is absolute for transitive models of ZFC, in the sense that if $V \subseteq W$ are transitive models of ZFC with the same ordinals,…

Logic · Mathematics 2019-12-11 David Milovich , Ioannis Souldatos

Let $0<p\leq 1$, $\omega$ be a weight on $\mathbb Z$, and let $\mathcal A$ be a unital Banach algebra. If $f$ is a continuous function from the unit circle $\mathbb T$ to $\mathcal A$ such that $\sum_{n\in \mathbb Z} \|\widehat f(n)\|^p…

Functional Analysis · Mathematics 2022-10-11 Prakash A. Dabhi , Karishman B. Solanki

We prove the consistency of ``CH + 2^{aleph_1} is arbitrarily large + 2^{aleph_1} not-> (omega_1 x omega)^2_2''. If fact, we can get 2^{aleph_1} not-> [omega_1 x omega]^2_{aleph_0}. In addition to this theorem, we give generalizations to…

Logic · Mathematics 2009-09-25 Saharon Shelah

The \emph{Filter Dichotomy} says that every uniform nonmeager filter on the integers is mapped by a finite-to-one function to an ultrafilter. The consistency of this principle was proved by Blass and Laflamme. A function between topological…

Logic · Mathematics 2010-09-02 Paul B. Larson

We study some universal features of gravity in higher dimensions and by universal we mean a feature that remains true in all dimensions $\geq4$. They include: (a) the gravitational dynamics always follows from the Bianchi derivative of a…

General Relativity and Quantum Cosmology · Physics 2011-05-06 Naresh Dadhich