Other Equivalent Machines and Methods
- Multidimensional Turing machine: For example, a model by Schönhage (1980) uses the four head-movement commands { North, South, East, West }.
- Single-tape, multi-head Turing machine: In an undecidability proof of the "problem of tag", Minsky 1961 and Shepherdson and Sturgis (1963) described machines with a single tape that could write along the tape with one head and read further along the tape with another.
- Markov Algorithm (1960) is another remarkably simple computational model, based on string rewriting, equivalent to the Turing machines.
- Lambda calculus
- Queue automaton
Read more about this topic: Turing Machine Equivalents
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