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Minimal usco and minimal cusco maps and the topology of pointwise convergence

  • Dušan Holý EMAIL logo
Veröffentlicht/Copyright: 9. August 2025
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Abstract

Let X be a Hausdorff topological space, MU(X, ℝ) and MC(X, ℝ) be the space of all minimal usco maps with values in ℝ and the space of all minimal cusco maps with values in ℝ, respectively. By τp is denoted the topology of pointwise convergence. We characterize some cardinal invariants of (MU(X, ℝ), τp) and (MC(ℝ,ℝ), τp). Let Q(ℝ,ℝ) be the space of all quasicontinuous functions on ℝ with values in ℝ and C(ℝ,ℝ) the space of all continuous functions on ℝ with values in ℝ. We compare cardinal invariants of (MU(ℝ,ℝ), τp), (MC(ℝ,ℝ), τp), (Q(ℝ,ℝ), τp) and (C(ℝ,ℝ), τp).


The author thanks the referee for helpful comments. The author was supported by the grant APVV-20-0045.


  1. (Communicated by David Buhagiar)

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Received: 2025-02-07
Accepted: 2025-03-25
Published Online: 2025-08-09
Published in Print: 2025-08-26

© 2025 Mathematical Institute Slovak Academy of Sciences

Heruntergeladen am 26.10.2025 von https://www.degruyterbrill.com/document/doi/10.1515/ms-2025-0069/pdf
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