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Undecidable Problems in Unreliable Computations
 THEORETICAL COMPUTER SCIENCE
, 2000
"... Lossy counter machines are defined as Minsky ncounter 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 undecidability result has f ..."
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Cited by 59 (3 self)
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far reaching consequences. Lossy counter machines can be used as a general tool to prove the undecidability of many problems, for example (1) The verification of systems that model communication through unreliable channels (e.g. model checking lossy fifochannel systems and lossy vector addition
AN UNDECIDABLE PROBLEM FOR REGULAR EQUATIONS
"... This is a continuation of our note [4]. We deal with two kinds of special equations: normal and regular (see [4]). Our aim is to point an undecidable problem on regular (normal) equations. An extended version is submitted to Algebra Universalis. Preliminaries Our nomenclature and notation is basica ..."
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This is a continuation of our note [4]. We deal with two kinds of special equations: normal and regular (see [4]). Our aim is to point an undecidable problem on regular (normal) equations. An extended version is submitted to Algebra Universalis. Preliminaries Our nomenclature and notation
UNDECIDABLE PROBLEMS: A SAMPLER
, 2012
"... After discussing two senses in which the notion of undecidability is used, we present a survey of undecidable decision problems arising in various branches of mathematics. ..."
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Cited by 1 (0 self)
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After discussing two senses in which the notion of undecidability is used, we present a survey of undecidable decision problems arising in various branches of mathematics.
Decidable and Undecidable Problems in Matrix Theory
, 1997
"... This work is a survey on decidable and undecidable problems in matrix theory. The problems studied are simply formulated, however most of them are undecidable. The method to prove undecidabilities is the one found by Paterson [Pat] in 1970 to prove that the mortality of finitely generated matrix mon ..."
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Cited by 8 (2 self)
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This work is a survey on decidable and undecidable problems in matrix theory. The problems studied are simply formulated, however most of them are undecidable. The method to prove undecidabilities is the one found by Paterson [Pat] in 1970 to prove that the mortality of finitely generated matrix
HIGHLY UNDECIDABLE PROBLEMS FOR INFINITE COMPUTATIONS
 THEORETICAL INFORMATICS AND APPLICATIONS
, 2009
"... We show that many classical decision problems about 1counter ωlanguages, context free ωlanguages, or infinitary rational relations, are Π 1 2complete, hence located at the second level of the analytical hierarchy, and “highly undecidable”. In particular, the universality problem, the inclusion ..."
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Cited by 10 (8 self)
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We show that many classical decision problems about 1counter ωlanguages, context free ωlanguages, or infinitary rational relations, are Π 1 2complete, hence located at the second level of the analytical hierarchy, and “highly undecidable”. In particular, the universality problem, the inclusion
Undecidable Problems of Decentralized Observation and Control
, 2001
"... We introduce a new notion of decentralized observability for discreteevent systems, which we call joint observability. We prove that checking joint observability of a regular language w.r.t. one observer is decidable, whereas for two (or more) observers the problem becomes undecidable. Based on thi ..."
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Cited by 52 (4 self)
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We introduce a new notion of decentralized observability for discreteevent systems, which we call joint observability. We prove that checking joint observability of a regular language w.r.t. one observer is decidable, whereas for two (or more) observers the problem becomes undecidable. Based
Undecidable problems about timed automata
 IN PROCEEDINGS OF THE 4TH INTERNATIONAL CONFERENCE ON FORMAL MODELING AND ANALYSIS OF TIMED SYSTEMS, FORMATS 2006
, 2006
"... We solve some decision problems for timed automata which were raised by S. Tripakis in [Tri04] and by E. Asarin in [Asa04]. In particular, we show that one cannot decide whether a given timed automaton is determinizable or whether the complement of a timed regular language is timed regular. We show ..."
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Cited by 13 (2 self)
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show that the problem of the minimization of the number of clocks of a timed automaton is undecidable. It is also undecidable whether the shuffle of two timed regular languages is timed regular. We show that in the case of timed Büchi automata accepting infinite timed words some of these problems are Π
Undecidable Problems of Decentralized Observation and Control
"... We introduce a new notion of decentralized observability for discreteevent systems, which we call joint observability. We prove that checking joint observability of a regular language w.r.t. one observer is decidable, whereas for two (or more) observers the problem becomes undecidable. Based on thi ..."
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We introduce a new notion of decentralized observability for discreteevent systems, which we call joint observability. We prove that checking joint observability of a regular language w.r.t. one observer is decidable, whereas for two (or more) observers the problem becomes undecidable. Based
Undecidable problems concerning densities of languages
"... In this paper we prove that the question whether a language presented by a context free grammar has density, is undecidable. Moreover we show that there is no algorithm which, given two unambiguous context free grammars on input, decides whether the language defined by the first grammar has a relati ..."
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relative density in the language defined by the second one. Our techniques can be extended to show that this problem is undecidable even for languages given by grammars from LL(k) (for sufficiently large fixed k ∈ N).
Results 1  10
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1,892