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Related papers: Topologically invariant $\sigma$-ideals on the Hil…

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We study and classify topologically invariant sigma-ideals with an analytic base on Euclidean spaces and evaluate the cardinal characteristics of such ideals.

Logic · Mathematics 2016-02-23 Taras Banakh , Michał Morayne , Robert Rałowski , Szymon Żeberski

Let $X$ be a zero-dimensional compact metrizable space endowed with a strictly positive continuous Borel $\sigma$-additive measure $\mu$ which is good in the sense that for any clopen subsets $U,V\subset X$ with $\mu(U)<\mu(V)$ there is a…

General Topology · Mathematics 2016-02-19 Taras Banakh , Robert Ralowski , Szymon Zeberski

Let $\mu$ be a Borel measure on a compactum $X$. The main objects in this paper are $\sigma$-ideals $I(dim)$, $J_0(\mu)$, $J_f(\mu)$ of Borel sets in $X$ that can be covered by countably many compacta which are finite-dimensional, or of…

Logic · Mathematics 2017-06-16 Roman Pol , Piotr Zakrzewski

This paper provides an extensive study of the $\mathscr{I}$-Miller null ideals $M_\mathscr{I}$, $\sigma$-ideals on the Baire space parametrized by ideals $\mathscr{I}$ on countable sets. These $\sigma$-ideals are associated to the idealized…

We examine topological spaces not distinguishing ideal pointwise and ideal $\sigma$-uniform convergence of sequences of real-valued continuous functions defined on them. For instance, we introduce a purely combinatorial cardinal…

General Topology · Mathematics 2023-08-21 Rafał Filipów , Adam Kwela

We introduce a two-parameter modification of the cofinality invariant of ideals. This allows us to include the interaction of a pair of ideals in the study of base-like structures. We find the values (cardinal numbers or well-known cardinal…

General Topology · Mathematics 2025-02-13 Adam Marton , Miroslav Repický

Here we shall consider the topology and dynamics associated to a wide class of matchbox manifolds, including a large selection of tiling spaces and all minimal matchbox manifolds of dimension one. For such spaces we introduce topological…

Dynamical Systems · Mathematics 2016-02-16 Alex Clark , John Hunton

For each countable ordinal $\alpha \ge 2$, the ideals $\mathsf{conv}_\alpha$ were introduced in ``Critical ideals for countable compact spaces'' (to appear in Fund. Math., see also arXiv:2503.12571) to characterize compact countable spaces…

Logic · Mathematics 2026-03-03 Malgorzata Kowalczuk

We study the Borel and analytic subsets of the spaces \({}^{\kappa}\kappa\) and \({}^{\kappa}2\) endowed with ideal topologies, where \(\kappa\) is a regular uncountable cardinal. We establish that the Borel hierarchy does not collapse in…

Logic · Mathematics 2025-12-25 Miguel Moreno , Beatrice Pitton

In this paper we formulate three problems concerning topological properties of sets generating Borel non-sigma-compact groups. In case of the concrete F_\sigma\delta-subgroup of the Cantor group this gives an equivalent reformulation of the…

General Topology · Mathematics 2007-05-23 Lyubomyr Zdomskyy

We prove upper bounds for the spread, the Lindel\"of number and the weak Lindel\"of number of the $G_\delta$-topology on a topological space and apply a few of our bounds to give a short proof to a recent result of Juh\'asz and van Mill…

General Topology · Mathematics 2017-07-18 Angelo Bella , Santi Spadaro

We discuss some bulk-surfaces gapped Hamiltonians on a lattice with corners and propose a periodic table for topological invariants related to corner states aimed at studies of higher-order topological insulators. Our table is based on four…

Mathematical Physics · Physics 2021-09-29 Shin Hayashi

We classify reflexive graded right ideals, up to isomorphism and shift, of generic cubic three dimensional Artin-Schelter regular algebras. We also determine the possible Hilbert functions of these ideals. These results are obtained by…

Rings and Algebras · Mathematics 2007-05-23 K. De Naeghel , N. Marconnet

We introduce a very natural topology on the set of total orderings of monomials of any algebra having a countable basis over a field. This topological space and some notable subspaces are compact. This topological framework allows us to…

Rings and Algebras · Mathematics 2011-06-02 Roberto Boldini

Given an analytic equivalence relation, we tend to wonder whether it is Borel. When it is non Borel, there is always the hope it will be Borel on a "large" set -- nonmeager or of positive measure. That has led Kanovei, Sabok and Zapletal to…

Logic · Mathematics 2016-05-31 Ohad Drucker

In this expositional paper, we discuss commutative algebra -- a study inspired by the properties of integers, rational numbers, and real numbers. In particular, we investigate rings and ideals, and their various properties. After, we…

Algebraic Geometry · Mathematics 2021-10-19 Marc Maliar

The concept of $\mathcal S$-topological $\sigma$-ideal in measurable space $(X, \mathcal S)$ was introduced by Hejduk and using a theorem of Wagner on convergence of measurable functions characterized $\mathcal S$-topological…

Functional Analysis · Mathematics 2023-05-01 Sanjib Basu , Debasish Sen

In this paper, we survey the theory of Cartwright-Sturmfels ideals. These are Z^n-graded ideals, whose multigraded generic initial ideal is radical. Cartwright-Sturmfels ideals have surprising properties, mostly stemming from the fact that…

Commutative Algebra · Mathematics 2021-08-24 A. Conca , E. De Negri , E. Gorla

In this paper, we study the translations into the Baire space of several well-known $\sigma$-ideals and families originally defined on the Cantor space, using their combinatorial characterizations. These include the ideals of null sets,…

General Topology · Mathematics 2025-11-03 Łukasz Mazurkiewicz , Marcin Michalski , Szymon Żeberski

We define a categorical birational invariant for minimal geometrically rational surfaces with a conic bundle structure over a perfect field via components of a natural semiorthogonal decomposition. Together with the similar known result on…

Algebraic Geometry · Mathematics 2019-09-30 Marcello Bernardara , Sara Durighetto
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