A Lindström characterisation of the guarded fragment and of modal logic with a global modality
نویسندگان
چکیده
We establish a Lindström type characterisation of the extension of basic modal logic by a global modality (ML[∀]) and of the guarded fragment of first-order logic (GF) as maximal among compact logics with the corresponding bisimulation invariance and the Tarski Union Property.
منابع مشابه
M ay 2 00 9 LINDSTRÖM THEOREMS FOR FRAGMENTS OF FIRST - ORDER LOGIC ∗
Lindström theorems characterize logics in terms of model-theoretic conditions such as Compactness and the Löwenheim-Skolem property. Most existing characterizations of this kind concern extensions of first-order logic. But on the other hand, many logics relevant to computer science are fragments or extensions of fragments of first-order logic, e.g., k-variable logics and various modal logics. F...
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