Results 1 to 10 of about 50 (45)
Absolutely strongly star-Hurewicz spaces
Open Mathematics, 2015 A space X is absolutely strongly star-Hurewicz if for each sequence (Un :n ∈ℕ/ of open covers of X and each dense subset D of X, there exists a sequence (Fn :n ∈ℕ/ of finite subsets of D such that for each x ∈X, x ∈St(Fn; Un) for all but finitely many n.
Song Yan-Kui
doaj +3 more sources
The Absolutely Strongly Star-Hurewicz Property with Respect to an Ideal
Tatra Mountains Mathematical Publications, 2020 Abstract Aspace X is said to have the absolutely strongly star --Hurewicz (ASSH) property if for each sequence (𝒰 n : n ∈ )of opencovers of
Sumit Singh, Manoj Bhardwaj
exaly +2 more sources
Remarks on strongly star-Hurewicz spaces
Filomat, 2013 A space X is strongly star-Hurewicz if for each sequence (Un : n ∈ N) of open covers of X there exists a sequence (An : n ∈ N) of finite subsets of X such that for each x ∈ X, x ∈ St(An; Un) for all but finitely many n. In this paper, we continue to investigate topological properties of strongly star-Hurewicz spaces.
Yan-Kui Song, Song Yan-Kui
exaly +3 more sources
Open Mathematics, 2019 In this paper we define and investigate nearly Hurewicz spaces and their star version. It is shown that a nearly Hurewicz space fits between Hurewicz and almost Hurewicz spaces.
Aqsa, Khan Moiz ud Din
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Some properties defined by relative versions of star-covering properties II
Applied General Topology, 2023 In this paper we consider some recent relative versions of Menger property called set strongly star Menger and set star Menger properties and the corresponding Hurewicz-type properties. In particular, using [2], we "easily" prove that the set strong star
Maddalena Bonanzinga +2 more
doaj +1 more source
Selection principles and covering properties in bitopological spaces
Applied General Topology, 2020 Our main focus in this paper is to introduce and study various selection principles in bitopological spaces. In particular, Menger type, and Hurewicz type covering properties like: Almost p-Menger, star p-Menger, strongly star p-Menger, weakly p-Hurewicz,
Moiz ud Din Khan, Amani Sabah
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Counterexample of theorems on star versions of Hurewicz property
Applied General Topology, 2020 In this paper, an example contradicting Theorem 4.5 and Theorem 5.3 is provided and these theorems are proved under some extra hypothesis.
Manoj Bhardwaj
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Strongly invertible knots, equivariant slice genera, and an equivariant algebraic concordance group
Journal of the London Mathematical Society, Volume 107, Issue 6, Page 2025-2053, June 2023., 2023 Abstract We use the Blanchfield form to obtain a lower bound on the equivariant slice genus of a strongly invertible knot. For our main application, let K$K$ be a strongly invertible genus one slice knot with nontrivial Alexander polynomial. We show that the equivariant slice genus of an equivariant connected sum #nK$\#^n K$ is at least n/4$n/4$.
Allison N. Miller, Mark Powell
wiley +1 more source
Group and Lie algebra filtrations and homotopy groups of spheres
Journal of Topology, Volume 16, Issue 2, Page 822-853, June 2023., 2023 Abstract We establish a bridge between homotopy groups of spheres and commutator calculus in groups, and solve in this manner the “dimension problem” by providing a converse to Sjogren's theorem: every abelian group of bounded exponent can be embedded in the dimension quotient of a group.
Laurent Bartholdi, Roman Mikhailov
wiley +1 more source
Simplicial volume and essentiality of manifolds fibered over spheres
Journal of Topology, Volume 16, Issue 1, Page 192-206, March 2023., 2023 Abstract We study the question when a manifold that fibers over a sphere can be rationally essential, or have positive simplicial volume. More concretely, we show that mapping tori of manifolds (whose fundamental groups can be quite arbitrary) of dimension 2n+1⩾7$2n +1 \geqslant 7$ with non‐zero simplicial volume are very common.
Thorben Kastenholz, Jens Reinhold
wiley +1 more source