Interactive computation

In computer science, interactive computation is a mathematical model for computation that involves input/output communication with the external world during computation. This is in contrast to the traditional understanding of computation which assumes reading input only before computation and writing output only after computation, thus defining a kind of "closed" computation.

The famous Church-Turing thesis attempts to define computation and computability in terms of Turing machines. However the Turing machine model only provides an answer to the question of what computability of functions means and, with interactive tasks not always being reducible to functions, it fails to capture our broader intuition of computation and computability. While this fact was admitted by Alan Turing himself, it was not until recently that the theoretical computer science community realized the necessity to define adequate mathematical models of interactive computation. Among the currently studied mathematical models of computation that attempt to capture interaction are Japaridze's hard- and easy-play machines elaborated within the framework of computability logic, Goldin's persistent Turing machines, and Gurevich's abstract state machines. Peter Wegner has additionally done a great deal of work on this area of computer science.

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