The Goldblatt-Thomason Theorem for Coalgebras
نویسندگان
چکیده
Goldblatt and Thomason’s theorem on modally definable classes of Kripke frames and Venema’s theorem on modally definable classes of Kripke models are generalised to coalgebras.
منابع مشابه
Goldblatt-Thomason Theorem for Coalgebraic Graded Modal Logic
Graded modal logic (GML) was originally presented by Kit Fine (1972) to make the modal analogue to counting quantifiers explicit. A graded modal formula ♦k is true at a state w in a Kripke model if there are at least k successor states of w where φ is true. One open problem in GML is to show a Goldblatt-Thomason theorem for it. See M. De Rijke’s notes (2000). Recently, Katsuhiko Sano and Minghu...
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