Lawvere-Tierney topologies for computability theorists
نویسندگان
چکیده
In this article, we study the lattice of Lawvere-Tierney topologies on Hyland’s effective topos. For purpose, introduce a new computability-theoretic reducibility notion, which is common extension notions Turing and generalized Weihrauch reducibility. Based work by Lee van Oosten [Ann. Pure Appl. Logic 164 (2013), pp. 866-883], utilize notion for providing concrete description As an application, solve several open problems proposed Oosten. instance, show that there exists no minimal topology strictly above identity
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2023
ISSN: ['2330-0000']
DOI: https://doi.org/10.1090/btran/134