The Borel monadic theory of order is decidable
- Prelegent(ci)
- Sven Manthe
- Afiliacja
- University of Bonn
- Język referatu
- angielski
- Termin
- 4 września 2024 14:15
- Pokój
- p. 5050
- Tytuł w języku polskim
- The Borel monadic theory of order is decidable
- Seminarium
- Seminarium „Teoria automatów”
When proving decidability of S2S, Rabin derived decidability of the monadic theory of (ℝ,<) with quantification restricted to Fσ-sets. Undecidability of the unrestricted monadic theory of (ℝ,<) was proven by Shelah. We discuss decidability for Borel sets, or even σ-combinations of analytic sets. Moreover, the Boolean combinations of Fσ-sets yield the same theory. The proof relies on Baire category methods. Thus, under determinacy hypotheses, it extends to larger classes of sets.