## Can a Turing machine have infinite states?

No. The definition of Turing machines requires that the finite-state control unit have a finite number of states. It’s not allowed to have an infinite number of states. A machine that could have infinitely many states in its control could accept any language (unlike a Turing machine).

## What is infinite loop in Turing machine?

If you think of this in terms of Turing machines (a finite set of states plus an infinite tape to write on), then an infinite loop looks like being in exactly the same finite state twice with exactly the same tape contents.

**Can Turing machines have infinite loops?**

YES! No Turing machine can infallibly tell in advance if another Turing machine will get stuck in an infinite loop on some given input. Example: Looper TM eventually halts on input 0000bbb… but gets stuck in an infinite loop on input 0000111bbb…

**Can a Turing machine detect a loop?**

This procedure will detect all infinite loops in which the Turing machine repeats a state, and no others. If you restrict your Turing machine’s head to be within certain bounds, then it can only be in a finite number of states, and so if it never halts, it must repeat a state twice.

### What is Turing complete programming language?

Practically, what you need to know is that a Turing-complete language (also called a universal language) is one where you can compute anything that any other computational method can compute. In other words, a language that’s non-universalâ€”or Turing incompleteâ€”has some limits on the set of things that it can compute.

### What 3 structures are required to be considered a Turing complete language?

Non-mathematical usage In contrast, a universal computer is defined as a device with a Turing-complete instruction set, infinite memory, and infinite available time.

**How do I know if my language is Turing complete?**

One way determine whether a programming language is Turing complete is to write a Turing machine in it (or an implementation of the Lambda calculus). Another way is to prove that all mu-recursive functions http://en.wikipedia.org/wiki/%CE%9C-recursive_function can be computed by the programming language.

**What makes something Turing complete?**

A Turing Complete system means a system in which a program can be written that will find an answer (although with no guarantees regarding runtime or memory). So, if somebody says “my new thing is Turing Complete” that means in principle (although often not in practice) it could be used to solve any computation problem.

#### Are Excel macros Turing-complete?

With the addition of custom functions that can call each other and recursively call themselves, Excel’s formula language becomes Turing-complete, effectively meaning that Excel users can compute anything without resorting to another programming language.

#### What is the difference between a Turing machine and infinite state machine?

Finite state machines (FSM) are strictly less powerful than turing machines (TM). But this is not the case with infinite state machines (ISM). For example, every TM can be embedded into some ISM.

**Can every TM be embedded in an infinite state machine?**

But this is not the case with infinite state machines (ISM). For example, every TM can be embedded into some ISM. The opposite (that for every ISM there exists a TM that can be embedded within the ISM), however, is not true.

**Do extended Turing machines increase the power of a computer?**

They may bring greater convenience; they may speed up a computation. But none ofthem has increased the power. There are no problems that extended Turing machinescan solve that standard Turing machines cannot solve.

## How does an infinite state machine decide which language to choose?

This produces an infinite state machine which decides the language L. In particular, it decides L regardless of whether L is even computable, and even regardless of its position in the arithmetic hierarchy.