Far beyond Goodman's Theorem?

Michael Rathjen (U Leeds)

21-Oct-2020, 09:00-10:00 (5 years ago)

Abstract: Goodman's Theorem says that Heyting arithmetic in all finite types, HA^{\omega}, augmented by the axiom of choice for all finite types, AC(FT), is conservative over HA. This classical result has been extended to many other intuitionistic theories (e.g. by Beeson) and even to intuitionistic Zermelo-Fraenkel set theory with large set axioms (by Friedman and Scedrov).The question I'll be pondering in this talk is whether the finite types are the limit.What about adding the axiom of choice for all the transfinite dependent types as they appear in Martin-Löf type theory (actually already in Hilbert's "Über das Unendliche")?

logic in computer sciencelogic

Audience: researchers in the topic


Proof Theory Virtual Seminar

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