Between the classes of semi-Eberlein and Valdivia compact spaces

Prelegent(ci)

Maksymilian Wesoły

Afiliacja

University of Warsaw

Język referatu

polski

Termin

3 czerwca 2026 16:15

Pokój

p. 4050

Seminarium

Seminarium „Topologia i teoria mnogości”

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Recently Todorcevic has introduced the hierarchy of E_2(\theta) compact spaces. Motivated by the definition of Valdivia compact spaces, we introduce a corresponding hierarchy of semi-E_2(\theta) compacta. We investigate how these classes behave under Alexandroff duplicates. In particular, we show that if K is a compact space, then the Alexandroff duplicate of K is E_2(\theta) if and only if it is semi-E_2(\theta). This result yields examples distinguishing some of the classes in the hierarchy. It may also be considered a partial answer to a question posed by Kalenda. 
This is joint work with Antonio Avilés and Mikołaj Krupski. 

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