English
Related papers

Related papers: How you are with $\mathfrak{s}$ and $\mathfrak{r}$…

200 papers

We introduce and analyze a new cardinal characteristic of the continuum, the \emph{splitting number of the reals}, denoted $\mathfrak{s}(\mathbb R)$. This number is connected to Efimov's problem, which asks whether every infinite compact…

Logic · Mathematics 2019-01-21 Will Brian , Alan Dow

The paper establishes several inequalities between cardinal characteristics of the continuum. In particular, it is shown that the partition splitting number is not larger than the uniformity of the meagre ideal; not all sets of reals having…

Logic · Mathematics 2026-03-19 Thilo Weinert

In this article we investigate the dual-shattering cardinal H, the dual-splitting cardinal S and the dual-reaping cardinal R, which are dualizations of the well-known cardinals h (the shattering cardinal, also known as the distributivity…

Logic · Mathematics 2007-05-23 Lorenz Halbeisen

We prove that if there is an elementary embedding from the universe to itself, then there is a proper class of measurable successor cardinals.

Logic · Mathematics 2021-11-03 Gabriel Goldberg

Dealing with the cardinal invariants p and t of the continuum we prove that m=p=aleph_2 -> t = aleph_1. In other words if MA_{aleph_1} (or a weak version of this) then (of course aleph_2 <= p <= t and) p = aleph_2 -> p = t . This is based…

Logic · Mathematics 2017-08-08 Saharon Shelah

Let $f \colon X \rightarrow Y$ be a resolvable-measurable mapping of a metrizable space $X$ to a regular space $Y$. Then $f$ is piecewise continuous. Additionally, for a metrizable completely Baire space $X$, it is proved that $f$ is…

General Topology · Mathematics 2016-08-03 Sergey Medvedev

We propose a reinterpretation of the continuum grounded in the stratified structure of definability rather than classical cardinality. In this framework, a real number is not an abstract point on the number line, but an object expressible…

General Mathematics · Mathematics 2025-05-28 Stanislav Semenov

We can generalize the definition of {\it splitting number } $s(\kappa )$ for $\kappa$ uncountable regular: $s(\kappa )=min\{ |\Cal S|:\Cal S\subset \Cal P(\kappa ) \forall a\in \kappa ^\kappa \exists b\in \Cal S |a\cap b|=|a\setminus…

Logic · Mathematics 2008-02-03 Jindřich Zapletal

If it is consistent that there is a measurable cardinal, then it is consistent that all points g-delta Rothberger spaces have "small" cardinality.

General Topology · Mathematics 2010-01-29 Marion Scheepers

Suppose that there is a measurable cardinal. If \aleph_\omega is a strong limit cardinal, but the power of \aleph_\omega is bigger than \aleph_{\omega_1}, then there is an inner model with a Woodin cardinal. Modulo the need of the…

Logic · Mathematics 2007-05-23 Ralf Schindler

A proof that the set of real numbers is denumerable is given.

General Mathematics · Mathematics 2013-07-17 Jailton C. Ferreira

In this paper, we show that the existence of certain first-countable compact-like extensions is equivalent to the equality between corresponding cardinal characteristics of the continuum. For instance, $\mathfrak b=\mathfrak s=\mathfrak c$…

Logic · Mathematics 2025-02-19 Serhii Bardyla , Peter Nyikos , Lyubomyr Zdomskyy

We investigate some variants of the splitting, reaping, and independence numbers defined using asymptotic density. Specifically, we give a proof of Con($\mathfrak{i}<\mathfrak{s}_{1/2}$), Con($\mathfrak{r}_{1/2}<\mathfrak{b}$) and…

Logic · Mathematics 2025-11-05 David Valderrama

We continue investigating variants of the splitting and reaping numbers introduced in arXiv:1808.02442. In particular, answering a question raised there, we prove the consistency of $\mathrm{cof}(\mathcal{M})<\mathfrak{s}_{\frac{1}{2}}$ and…

Logic · Mathematics 2025-09-19 Barnabás Farkas , Lukas Daniel Klausner , Marc Lischka

We show how to construct, via forcing, splitting families than are preserved by a certain type of finite support iterations. As an application, we construct a model where 15 classical characteristics of the continuum are pairwise different,…

Logic · Mathematics 2024-04-18 Martin Goldstern , Jakob Kellner , Diego A. Mejía , Saharon Shelah

We prove that the strong polarized relation of $\theta$ above $\omega$ applied simultaneously for every cardinal in the interval $[\aleph_1,\aleph]$ is consistent. We conclude that this positive relation is consistent for every cardinal…

Logic · Mathematics 2018-04-24 Shimon Garti , Saharon Shelah

It is proved to be consistent relative to a measurable cardinal that there is a uniform ultrafilter on the real numbers which is generated by fewer than the maximum possible number of sets. It is also shown to be consistent relative to a…

Logic · Mathematics 2019-04-05 Dilip Raghavan , Saharon Shelah

This report presents an expression for the number of a multiset's sub-multisets of a given cardinality as a function of the multiplicity of its elements. This is also the number of distinct samples of a given size that may be produced by…

Combinatorics · Mathematics 2015-11-20 Sebastiano Ferraris , Alex Mendelson , Gerardo Ballesio , Tom Vercauteren

We indicate a way of distinguishing between structures, for which, two structures are said to be separable.Being separable implies being non-isomorphic. We show that for any first order theory $T$ in a countable language, if it has an…

Logic · Mathematics 2012-11-28 Mohammad Assem

Every conditionally convergent series of real numbers has a divergent subseries. How many subsets of the natural numbers are needed so that every conditionally convergent series diverges on the subseries corresponding to one of these sets?…

Logic · Mathematics 2018-01-22 Jörg Brendle , Will Brian , Joel David Hamkins
‹ Prev 1 2 3 10 Next ›