Highly Undecidable Problems For Infinite Computations
نویسندگان
چکیده
منابع مشابه
Highly Undecidable Problems For Infinite Computations
We show that many classical decision problems about 1counter ω-languages, context free ω-languages, or infinitary rational relations, are Π12-complete, hence located at the second level of the analytical hierarchy, and “highly undecidable”. In particular, the universality problem, the inclusion problem, the equivalence problem, the determinizability problem, the complementability problem, and t...
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Department of Computer Science, University of Edinburgh, JCMB, Edinburgh EH9 3JZ, UK. e-mail: [email protected] Abstract. Lossy counter machines are defined as Minsky n-counter machines where the values in the counters can spontaneously decrease at any time. While termination is decidable for lossy counter machines, structural termination (termination for every input) is undecidable. This und...
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Altenbernd, Thomas and Wöhrle have considered acceptance of languages of infinite two-dimensional words (infinite pictures) by finite tiling systems, with usual acceptance conditions, such as the Büchi and Muller ones, in [1]. It was proved in [9] that it is undecidable whether a Büchirecognizable language of infinite pictures is E-recognizable (respectively, A-recognizable). We show here that ...
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Let S be a Steinitz Exchange System with closure operation cl (see e.g. [5] for definitions). In this paper we examine the logical complexity of the first-order theory of the lattice of cl-closed subsets of S. (In the first-order language for lattices we use symbols for meet, join, and the elements zero and one.) As quantification over the elements of the lattice is quantification over some of ...
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We show Σ 1-completeness of weak bisimilarity for PA (process algebra), and of weak simulation preorder/equivalence for PDA (pushdown automata), PA and PN (Petri nets). We also show Π 1 hardness of weak ω-trace equivalence for the (sub)classes BPA (basic process algebra) and BPP (basic parallel processes).
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ژورنال
عنوان ژورنال: RAIRO - Theoretical Informatics and Applications
سال: 2009
ISSN: 0988-3754,1290-385X
DOI: 10.1051/ita/2009001