Path: ...!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Mikko Newsgroups: comp.theory Subject: Re: Every D(D) simulated by H presents non-halting behavior to H ### Date: Thu, 23 May 2024 13:06:31 +0300 Organization: - Lines: 68 Message-ID: References: <-5Gdnf-nQvstC6b7nZ2dnZfqnPadnZ2d@brightview.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Thu, 23 May 2024 12:06:31 +0200 (CEST) Injection-Info: dont-email.me; posting-host="cf913c4199a735193557ed034232fdcc"; logging-data="1798407"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18n78S9+kj9O4gHmx4oThtt" User-Agent: Unison/2.2 Cancel-Lock: sha1:HcUOrpSBufQ0R68LYD1DnxGPDXM= Bytes: 4497 On 2024-05-22 14:51:50 +0000, olcott said: > On 5/22/2024 2:39 AM, Mikko wrote: >> On 2024-05-21 13:54:09 +0000, olcott said: >>> You are asking for the definition of correct simulation >>> that I have been providing for quite a while recently. >> >> That was not my main intent. I wanted to know why your >> statement >> >>>>>>>>> No D simulated correctly by any H of every H/D pair specified >>>>>>>>> by the above template ever reaches its own line 06 and halts. >> >> exludes every unsimulated or incorrectly simulated D? > > That sounds like Richard that assumed that incorrect answers are OK > unless I specifically say that incorrect answers are not OK. Maybe but I don't promise that the response to the incorrect answer will sound the same. > On 5/19/2024 12:17 PM, Richard Damon wrote: > > On 5/19/24 9:59 AM, olcott wrote: > >> Richard has stated that he thinks that an example of > >> {D never simulated by H} ∈ {every D simulated by H} > > > > No, the H that didn't simulate its input shows that > > *once you allow H to not be required to be correct*, > > that we can then have a trivial function that is > > "just as correct" (since wrong answers were allowed). > >>> A c function is correctly simulated when its machine language >>> instructions are emulated with an x86 emulator in the order >>> that they are specified by the x86 machine language of this >>> c function. >> >> Does "its machine language instructions" mean all executed instructions >> until the progam terminates? Or from the start of the program until >> there is no reason to continue? Or from some point to some other point? >> > > It means that 1 to N instructions of D are correctly simulated > by pure function H. Because D correctly simulated by H remains > stuck in recursive simulation D cannot possibly reach is own > line 06 and halt. If you mean that H cannot simulate D to the line 06 then say so. A D that is simulated by H is D and so is a D that is not simulated by H so both can do what a D can do. Saying "simulated by H" adds nothing. >>> For non-terminating functions we can only correctly >>> simulate N machine language instructions. >> >> But does you definition regard that partial simulation as "correct >> simulation"? > > When 1 to 2^64 instructions of D are correctly simulated by H > it becomes clear that for every H/D pair of the infinite set > of H/D pairs D correctly simulated by H remains stuck in recursive > simulation. If you think that the meaning of "correctly simulate" is not important you should not use those words. -- Mikko