Initiality, induction, and computability
Algebraic methods in semantics
Theory of recursive functions and effective computability
Theory of recursive functions and effective computability
Complexity and real computation
Complexity and real computation
Neural networks and analog computation: beyond the Turing limit
Neural networks and analog computation: beyond the Turing limit
The unknowable
Sparse Distributed Memory
Elements of the Theory of Computation
Elements of the Theory of Computation
Minds and Machines
Recipes, Algorithms, and Programs
Minds and Machines
Chaos and Fractals
Hypercomputation by definition
Theoretical Computer Science - Super-recursive algorithms and hypercomputation
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The Church-Turing Thesis (CTT) is often paraphrased as ``every computable function is computable by means of a Turing machine.'' The author has constructed a family of equational theories that are not Turing-decidable, that is, given one of the theories, no Turing machine can recognize whether an arbitrary equation is in the theory or not. But the theory is called pseudorecursive because it has the additional property that when attention is limited to equations with a bounded number of variables, one obtains, for each number of variables, a fragment of the theory that is indeed Turing-decidable. In a 1982 conversation, Alfred Tarski announced that he believed the theory to be decidable, despite this contradicting CTT. The article gives the background for this proclamation, considers alternate interpretations, and sets the stage for further research.