Can a Turing machine recognize another Turing machine?

Turing machines can “simulate” other Turing machines. For example, there is a “universal turing machine” U, which will accept the string “M,x” if the machine M would accept x, will reject the string “M,x” if M would reject x, and will run forever if M would run forever on input x.

Which Turing machine can simulate other Turing machines?

universal Turing machine
An important concept is the ‘universal Turing machine,’ which is a special Turing machine that is capable of simulating any other Turing machine, if a description of that machine is provided as input on the tape.

How does the Universal Turing Machine simulate other Turing machines?

Similarly, the universal TM can simulate other Turing machines using its own data as a TM and its input. This is just like the CPU simulating a program by using its own data. The simulated Turing machines are encoded by using the input symbols of the UTM, just like the programs are encoded by the input symbols of CPU.

Can a Turing machine have no accepting states?

Turing machines are defined to have only a finite number of states. Since every accepting state is a state, it’s impossible to have infinitely many accepting states. Being allowed to have more than one of something is not the same as being allowed to have infinitely many.

Which string is rejected by the Turing machine?

M
3. A string is rejected by a Turing machine M if either M enters the qrejectstate while processing w, or if M never halts in the processing of w. 4. A language L is called Turing recognizable or Recursively Enumerable if there exists some Turing machine, M, such that L = L(M).

Does a Turing machine accept any string?

Let’s assume that L∀ is recognizable, and a Turing machine T recognizes it. This means for any Turing machine M that accepts all strings, T ( ⟨ M ⟩ ) T(\langle M\rangle ) T(⟨M⟩) will halt eventually in an ACCEPT state.

Which of the following can be used to simulate any TM?

5. Which of the following can be used to simulate any turing machine? Explanation: The computational aspect of any possible real world computer can be simulated using an Universal Turing Machine so can be any turing machine.

Is Turing recognizable languages are closed under union?

Theorem 5: The set of Turing-recognizable languages is closed under set union and intersection.

Can a universal turing machine simulate itself?

7 A Universal Turing Machine can simulate the operation of any Turing machine, including itself, in polynomial time.

Is the input of universal turing machine in TOC?

The Turing Machine (TM) is the machine level equivalent to a digital computer. This is the reason the Universal Turing machine was introduced which along with input on the tape takes the description of a machine M. …

Can a Turing machine only have one state?

At first glance, one-state Turing machines are very weak: the halting problem for them is decidable, and, without memory, they cannot even accept a simple one element language such as L = \{ 1 \} ….The Power of One-State Turing Machines.

How many accepting states can a Turing machine have?

It can be done with 5 states.