Turing Machine structure

Creator
Creator
Seonglae ChoSeonglae Cho
Created
Created
2023 Oct 6 8:20
Editor
Edited
Edited
2023 Dec 19 4:36
Refs
Refs
Turing Machine structures
math: M = (Q ,\Sigma, \Gamma, \delta, q_0, B, F)
  1. Q is finite set of control states
  1. math: \Sigma is finite set of input symbols
  1. math: \Gamma \supseteq \Sigma is a finite set of tape symbol
  1. math: q_0 \in Q is the start (initial state)
  1. math: B \in \Gamma is the blank symbol
  1. math: F \subseteq Q is the set of final (accepting) states
  1. math: \delta : Q \times \Gamma → Q \times \Gamma \times\{L, R\} is transition function which describe finite control by control stage and symbol

Property

  • Initially, the tape head is at the leftmost cell of the input right of B
  • Since we have infinite table, so we cannot apply high level description for finite table
  • since we have reusability we can call other subroutines by another Turing machine
  • Unary data is easy to manipulate with Turing machines
  • We need O(1) time & space to describe a state
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  • δ(q,X) = (p,Y,D) - overwrite X with Y in q
Based on the “scanned” symbol and the current state of the finite control, the macine does the following in one move
(a) Change its state
(b) Overwite a new symbol on the tape cell being currently scanned; it could rewrite the same symbol that was read
(c) Move the tape head left or right
 
 
 
 
The machine halts if there are no possible transitions to follow
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Deterministic operation

Only one transition per symbol for each state
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Function

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computable function
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Tape

We can simulate steps of a
RAM
-machine with a 3-tape TN in
Cubic complexity
steps. Vice-versa in steps.
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