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Related papers: Some remarks on Kuratowski partitions

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In this paper we present a few properties of $K$-partitions, which are partitions of Baire spaces such that all subfamilies of such a partition sum to a set with the Baire property. Among the result proven we have general existence result…

Logic · Mathematics 2022-05-26 Sławomir Kusiński

We investigate the properties of ideals associated with Kuratowski partitions of non-complete Baire metric spaces. We show that such an ideal can be precipitous.

Logic · Mathematics 2020-03-31 Ryszard Frankiewicz , Joanna Jureczko

We prove that the existence of a complete metric space of cardinality at most $2^{\kappa}$ admitting Kuratowski partition is a consequence of $\kappa$ being the smallest real-valued measurable cardinal not greater than $ 2^{\aleph_0}$.

Logic · Mathematics 2023-05-23 Joanna Jureczko

The main result of this paper is to show that, if $\kappa$ is the smallest real-valued measurable cardinal not greater than $ 2^{\aleph_0}$, then there exists a complete metric space of cardinality not greater than $ 2^{\kappa}$ admitting a…

Logic · Mathematics 2020-12-22 Ryszard Frankiewicz , Joanna Jureczko

In this note we give equivalence of the existence of K-partitions with the existence of the precipitous ideal which is essentially topological. This way we strengthen the main result of Frankiewczi and Kunen (1987).

Logic · Mathematics 2020-10-21 Ryszard Frankiewicz , Joanna Jureczko

From large cardinals we show the consistency of normal, fine, $\kappa$-complete $\lambda$-dense ideals on $\mathcal{P}_\kappa(\lambda)$ for successor $\kappa$. We explore the interplay between dense ideals, cardinal arithmetic, and squares,…

Logic · Mathematics 2023-03-27 Monroe Eskew

We show some basic results on the characterization of quasi-Polish spaces in terms of spaces of ideals, with an emphasis on the connections with computable topology.

Logic · Mathematics 2020-04-29 Matthew de Brecht

In this paper there is proved without any metamathematical techniques that the existence of precipitous ideals immediately follows from Kuratowski partitions.

Logic · Mathematics 2017-11-08 Ryszard Frankiewicz , Joanna Jureczko

In 1935 K. Kuratowski posed the problem whether a function f:X ! Y , (X is completely metrizable and Y is metrizable), with the property that a preimage of each open has the Baire property, is continuous apart from a meager set. This paper…

Logic · Mathematics 2017-06-28 Ryszard Frankiewicz , Joanna Jureczko

Building on work of Holy, L\"ucke and Njegomir \cite{MR3913154} on small embedding characterizations of large cardinals, we use some classical results of Baumgartner (see \cite{MR0384553} and \cite{MR0540770}), to give characterizations of…

Logic · Mathematics 2021-02-22 Brent Cody

For $\kappa$ regular and uncountable we define variants of the classical cardinal characteristics modulo the non-stationary ideal.

Logic · Mathematics 2021-05-18 Johannes Philipp Schürz

We present an overview of results on the question of whether the non-stationary ideal of an uncountable regular cardinal $\kappa$ can be defined by a $\Pi_1$-formula using parameters of hereditary cardinality at most $\kappa$. These results…

Logic · Mathematics 2024-04-18 Philipp Lücke

If $\kappa$ is regular and $2^{<\kappa}\leq\kappa^+$, then the existence of a weakly presaturated ideal on $\kappa^+$ implies $\square^*_\kappa$. This partially answers a question of Foreman and Magidor about the approachability ideal on…

Logic · Mathematics 2020-10-01 Sean Cox , Monroe Eskew

For I a proper, countably complete ideal on P(X) for some set X, can the quotient Boolean algebra P(X)/I be complete? This question was raised by Sikorski in 1949. By a simple projection argument as for measurable cardinals, it can be…

Logic · Mathematics 2008-02-03 Akihiro Kanamori , Saharon Shelah

We continue our study of Sierpinski-type colourings. In contrast to the prequel paper, we focus here on colourings for ideals stratified by their completeness degree. In particular, improving upon Ulam's theorem and its extension by Hajnal,…

Logic · Mathematics 2023-12-19 Tanmay Inamdar , Assaf Rinot

Given a compact Polish space $E$ and the hyperspace of its compact subsets $\mathcal{K}(E)$, we consider the class of $G_{\delta}$ $\sigma$-ideals of compact subsets of $E$ that can be represented via a compact subset of $\mathcal{K}(E)$.…

Logic · Mathematics 2019-02-26 Maya Saran

In the context of generalized descriptive set theory, we systematically compare and analyze various notions of Polish-like spaces and standard $\kappa$-Borel spaces for $\kappa$ an uncountable (regular) cardinal satisfying $\kappa^{<\kappa}…

Logic · Mathematics 2023-06-21 Claudio Agostini , Luca Motto Ros , Philipp Schlicht

Inspired by Bartoszy\'nski's work on small sets, we introduce a new ideal defined by interval partitions on natural numbers and summable sequences of positive reals. Similarly, we present another ideal that relies on Bartoszy\'nski's and…

Logic · Mathematics 2025-02-13 Miguel A. Cardona , Adam Marton , Jaroslav Supina

We show that many large cardinal notions up to measurability can be characterized through the existence of certain filters for small models of set theory. This correspondence will allow us to obtain a canonical way in which to assign ideals…

Logic · Mathematics 2021-12-09 Peter Holy , Philipp Lücke

For a strongly inacessible cardinal $\kappa$, we investigate the relationships between the following ideals: - the ideal of meager sets in the ${<}\kappa$-box product topology - the ideal of "null" sets in the sense of [Sh:1004]…

Logic · Mathematics 2023-05-04 Thomas Baumhauer , Martin Goldstern , Saharon Shelah
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