The logarithmic alternation hierarchy collapses: AΣ2L = AΠ2L
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چکیده
منابع مشابه
The \mu-Calculus Alternation Hierarchy Collapses over Structures with Restricted Connectivity
It is known that the alternation hierarchy of least and greatest fixpoint operators in the μ-calculus is strict. However, the strictness of the alternation hierarchy does not necessarily carry over when considering restricted classes of structures. A prominent instance is the class of infinite words over which the alternation-free fragment is already as expressive as the full μ-calculus. Our cu...
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It is known that the alternation hierarchy of least and greatest fixpoint operators in the μ-calculus is strict. However, the strictness of the alternation hierarchy does not necessarily carry over when considering restricted classes of structures. A prominent instance is the class of infinite words over which the alternation-free fragment is already as expressive as the full μ-calculus. Our cu...
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ژورنال
عنوان ژورنال: Information and Computation
سال: 1989
ISSN: 0890-5401
DOI: 10.1016/0890-5401(89)90012-6