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Related papers: Update: Remarks on Countable Tightness

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An emended and improved version of the present paper has been archived in math-ph/0505057, and a preliminary account of its content has been published in Phys.Rev.Lett. 92, 60601, (2004). Moreover, in order to prove the relevance of…

Mathematical Physics · Physics 2007-05-23 Roberto Franzosi , Marco Pettini , Lionel Spinelli

We adapt a construction taken from `L. Motto Ros and B. Semmes, A new proof of a theorem of Jayne and Rogers, Real Anal. Exchange 35(1) (2009/2010), 195-204' in order to correct a mistake contained in the first part of the same paper. As a…

Logic · Mathematics 2012-04-25 Miroslav Kačena , Luca Motto Ros , Brian Semmes

We continue the work of [4, 2, 3], in which we discuss published assertions that are incorrect or incorrectly proven; that are severely limited or reduce to triviality; or that we improve upon.

Geometric Topology · Mathematics 2020-01-31 Laurence Boxer

In this short note, it is shown that there is a gap in the proof of Theorem 11 in the paper of Meyer and Neutsch (J. of Algebra, 1993). We prove, nevertheless, that the statement of the theorem is true and fix the proof by using a certain…

Rings and Algebras · Mathematics 2018-03-09 Vladimir G. Tkachev

In this paper we correct an inaccuracy that appears in the proof of Theorem 1. in Czerwik's article "Contraction mappings in $b$-metric spaces.", Acta Math. Inform. Univ. Ostraviensis, 1:5--11, 1993.

Classical Analysis and ODEs · Mathematics 2019-03-22 Sándor Kajántó , Andor Lukács

In this note we improve the parameter $q$ that appears in Theorem 1 obtained by the author in [Math. Ineq. \& appl., Vol 19 (3) (2016), 1013-1030].

Classical Analysis and ODEs · Mathematics 2025-12-22 Pablo Rocha

A gap in the proof of Theorem 3.5 in the paper ``A new iteration process for approximation of common fixed points for finite families of total asymtotically nonexpansive mappings". Int. J. Math. Math. Sci. vol. 2009,…

Functional Analysis · Mathematics 2012-04-10 C. E. Chidume , E. U. Ofoedu

In this note, we demonstrate that an incorrect statement has been propagated in multiple papers, stemming from the substitution of ``lim'' with ``limsup'' for a sequence in Lemma 1.3 of the paper [J. Schu: Weak and strong convergence to…

Optimization and Control · Mathematics 2024-08-26 R. I. Bot , C. Zalinescu

This paper is a corrigendum to the article 'Some notes on the classification of shift spaces: Shifts of Finite Type; Sofic Shifts; and Finitely Defined Shifts'. In this article we correct Lemma 5.3. Therefore, we follow correcting…

Dynamical Systems · Mathematics 2025-11-07 Marcelo Sobottka

In this paper, we prove almost Schur Lemma on closed smooth metric measure spaces, which implies the results of X. Cheng and De Lellis-Topping whenever the weighted function f is constant.

Differential Geometry · Mathematics 2019-06-28 Jui-Tang Chen

Answering a question raised by V. V. Tkachuk, we present several examples of $\sigma$-compact spaces, some only consistent and some in ZFC, that are not countably tight but in which the closure of any discrete subset is countably tight. In…

General Topology · Mathematics 2024-11-08 István Juhász , Jan van Mill

In his 1979 paper Trotman proves, using the techniques of the Thom transversality theorem, that under some conditions on the dimensions of the manifolds under consideration, openness of the set of maps transverse to a stratification in the…

Differential Geometry · Mathematics 2015-04-30 Saurabh Trivedi

In this paper we make some observations concerning m-metric spaces and point out some discrepancies in the proofs found in the literature. To remedy this, we propose a new topological construction and prove that it is in fact a…

General Topology · Mathematics 2018-07-03 Samer Assaf

We prove a stronger version of a termination theorem appeared in the paper "On existence of log minimal models II". We essentially just get rid of the redundant assumptions so the proof is almost the same as in there. However, we give a…

Algebraic Geometry · Mathematics 2011-04-27 Caucher Birkar

We further develop the relationship between $\beta$-numbers and discrete curvatures to provide a new proof that under weak density assumptions, finiteness of the pointwise discrete curvature $\operatorname{curv}^{\alpha}_{\mu;2}(x,r)$ at…

Metric Geometry · Mathematics 2024-07-09 Silvia Ghinassi , Max Goering

In this note we look at the interdependences between James' theorem and the boundary problem. To do so we show a variant of James' sup-theorem for C(K)-spaces conjectured by Godefroy: in order to know that a bounded weakly closed subset of…

Functional Analysis · Mathematics 2012-01-27 Hermann Pfitzner

We consider 9 natural tightness conditions for topological spaces that are all variations on countable tightness and investigate the interrelationships between them. Several natural open problems are raised.

General Topology · Mathematics 2017-02-14 István Juhász , Jan Van Mill

The paper is devoted to a generalized and improved version of author's approach to Gromov bounded cohomology theory. In particular, the awkward countability assumption is removed and the aspects related to homological algebra are clarified.…

Algebraic Topology · Mathematics 2020-12-17 Nikolai V. Ivanov

The first version of this paper gave another proof of the Kropholler Conjecture, which gives a relative version of Stallings Ends Theorem, following an earlier incorrect proof. It has been pointed out by Sam Shepherd that the the second…

Group Theory · Mathematics 2023-11-27 M. J. Dunwoody

The primary purpose of this article is to prove a tightness of skew random walks. The tightness result implies, in particular, that the skew Brownian motion can be constructed as the scaling limit of such random walks. Our proof of…

Probability · Mathematics 2011-06-28 Youngsoo Seol