When cardinality determines the power set
Time
Friday, 14. June 2024
10:00 - 13:15
Location
D 435
Organizer
Leon Horsten, Carolin Antos, Sam Roberts
Speaker:
Philip Welch (University of Bristol)
Welch Talk Abstract:
We investigate when the predicate " x = Powerset(y)" can be Sigma_1(Card) where Card is a predicate for the cardinal numbers. This has relations to the Härtig quantifier logic which is intermediate between first and second order logic. We discuss Löwenheim-Skolem numbers for such a logic, and, to an extent, analyse the class of its validities. (This is joint work with Jouko Väänänen.)
When cardinality determines the power set
Time
Friday, 14. June 2024
10:00 - 13:15
Location
D 435
Organizer
Leon Horsten, Carolin Antos, Sam Roberts
Speaker:
Philip Welch (University of Bristol)
Welch Talk Abstract:
We investigate when the predicate " x = Powerset(y)" can be Sigma_1(Card) where Card is a predicate for the cardinal numbers. This has relations to the Härtig quantifier logic which is intermediate between first and second order logic. We discuss Löwenheim-Skolem numbers for such a logic, and, to an extent, analyse the class of its validities. (This is joint work with Jouko Väänänen.)