The hedge: An efficient storage device for Turing machines with one head
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Which kind of storage device should be used for a time-efficient simulation of multitape Turing machines on deterministic Turing machines with only one access head? In the literature, simulations on Turing machines accessing a tape, a multidimensional array, or a tree have been studied.
We advocate a new storage device for Turing machines, the “hedge.”
On a Turing machine accessing one hedge, multitape Turing machines can be simulated faster than on each of the traditional storage devices. E.g., we show how to simulate t(n) steps of a multitape Turing machine by O(t(n) log t(n)/log log t(n)) steps of a Turing machine accessing one hedge.
KeywordsStorage Device Turing Machine Data Track Meeting Place Simulation Track
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