Jirí Wiedermann

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The -rst attempts concerning formalization of the notion of fuzzy algorithms in terms of Turing machines are dated in late 1960s when this notion was introduced by Zadeh. Recently, it has been observed that corresponding so-called classical fuzzy Turing machines can solve undecidable problems. In this paper we will give exact recursion-theoretical(More)
Classical models of computation no longer fully correspond to the current notions of computing in modern systems. Even in the sciences, many natural systems are now viewed as systems that compute. Can one devise models of computation that capture the notion of computing as seen today and that could play the same role as Turing machines did for the classical(More)
Many IT-systems behave very differently from classical machine models: they interact with an unpredictable environment, they never terminate, and their behavior changes over time. Wegner [25,26] (see also [28]) recently argued that the power of interaction goes beyond the Church-Turing thesis. To explore interaction from a computational viewpoint, we(More)
Recent research in theoretical physics on ‘Malament-Hogarth space-times’ indicates that so-called relativistic computers can be conceived that can carry out certain classically undecidable queries in finite time. We observe that the relativistic Turing machines which model these computations recognize precisely theΔ2−sets of the Arithmetical Hierarchy. In a(More)
A finite automaton—the so-called neuromaton, realized by a finite discrete recurrent neural network, working in parallel computation mode, is considered. Both the size of neuromata (i.e., the number of neurons) and their descriptional complexity (i.e., the number of bits in the neuromaton representation) are studied. It is proved that a constraint(More)
The computational potential of artificial living systems can be studied without knowing the algorithms that govern their behavior. Modeling single organisms by means of socalled cognitive transducers, we will estimate the computational power of AL systems by viewing them as conglomerates of such organisms. We describe a scenario in which an artificial(More)