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From: olcott <polcott333@gmail.com>
Newsgroups: comp.theory
Subject: Re: How to write a self-referencial TM?
Date: Wed, 14 May 2025 12:24:36 -0500
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On 5/14/2025 11:43 AM, wij wrote:
> On Wed, 2025-05-14 at 09:51 -0500, olcott wrote:
>> On 5/14/2025 12:13 AM, wij wrote:
>>> Q: Write a turing machine that performs D function (which calls itself):
>>>
>>> void D() {
>>>    D();
>>> }
>>>
>>> Easy?
>>>
>>>
>>
>> That is not a TM.
> 
> It is a C program that exists. Therefore, there must be a equivalent TM.
> 
>> To make a TM that references itself the closest
>> thing is a UTM that simulates its own TM source-code.
> 
> How does a UTM simulate its own TM source-code?
> 

You run a UTM that has its own source-code on its tape.

-- 
Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer