Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: olcott Newsgroups: comp.theory Subject: Re: How do computations actually work? Date: Fri, 23 May 2025 13:19:57 -0500 Organization: A noiseless patient Spider Lines: 83 Message-ID: <100qe8d$71pk$2@dont-email.me> References: <100kt0c$2tae8$3@dont-email.me> <100ktr7$2reaa$1@dont-email.me> <100l09v$2tae8$5@dont-email.me> <100l1ov$2ul3j$1@dont-email.me> <100l3jh$2v0e9$1@dont-email.me> <100l5c8$2ul3j$2@dont-email.me> <100l75g$2vpq3$1@dont-email.me> <100l887$2ul3i$2@dont-email.me> <100l9gh$30aak$1@dont-email.me> <100lc4o$30pgm$1@dont-email.me> <100ld1u$312c9$1@dont-email.me> <100lg4g$31jt3$1@dont-email.me> <100lkdv$32ib3$1@dont-email.me> <100lmif$32v06$1@dont-email.me> <100lmp3$32ven$1@dont-email.me> <100m319$38k55$2@dont-email.me> <87jz69xlpx.fsf@nosuchdomain.example.com> <100mder$39slu$2@dont-email.me> <100oipb$3oge1$1@dont-email.me> <100onkd$3t5cb$1@dont-email.me> <100oq63$3tal2$1@dont-email.me> <100p792$3vnfa$1@dont-email.me> <100q6lb$5buc$3@dont-email.me> <59c4b521b93743e6bf00d003039a2d8057198714@i2pn2.org> <100q9jh$5buc$11@dont-email.me> <100qd9o$6j1f$3@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Fri, 23 May 2025 20:19:58 +0200 (CEST) Injection-Info: dont-email.me; posting-host="4606f99203c21d5702beb16569e2a0e8"; logging-data="231220"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19099reCtXKbKuP9e25H6rl" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:cVXkJ0yJFuB/+N9ossDx5zGpmJs= In-Reply-To: <100qd9o$6j1f$3@dont-email.me> X-Antivirus-Status: Clean X-Antivirus: Norton (VPS 250523-4, 5/23/2025), Outbound message Content-Language: en-US Bytes: 4968 On 5/23/2025 1:03 PM, Fred. Zwarts wrote: > Op 23.mei.2025 om 19:00 schreef olcott: >> On 5/23/2025 11:16 AM, Richard Damon wrote: >>> On 5/23/25 12:10 PM, olcott wrote: >>>> On 5/23/2025 2:14 AM, Mikko wrote: >>>>> On 2025-05-23 03:31:15 +0000, olcott said: >>>>> >>>>>> On 5/22/2025 10:23 PM, wij wrote: >>>>>>> On Thu, 2025-05-22 at 21:47 -0500, olcott wrote: >>>>>>>> [cut] >>>>>>> >>>>>>> Q: How do computations actually work? >>>>>>> A: Computation is merely step-by-step algorithm. >>>>>>> Nothing says it has to be TM. >>>>>>> >>>>>>> Do the exercises in textbooks first before any claim of it. >>>>>>> >>>>>> >>>>>> int main() >>>>>> { >>>>>>    DD(); // by what steps can the HHH that DD calls >>>>>> }       // report on the behavior its caller? >>>>> >>>>> If we don't insist that the report be correct: >>>>> 1. guess >>>>> 2. tell what was guessed >>>>> >>>> >>>> This does not work because all computable functions >>>> that implement termination analyzers must compute >>>> the mapping from their input finite string according >>>> to the behavior that it specifies. In my concrete >>>> examples DDD must be simulated by HHH according to the >>>> rules of the x86 language. >>>> >>>> _DDD() >>>> [00002172] 55         push ebp      ; housekeeping >>>> [00002173] 8bec       mov ebp,esp   ; housekeeping >>>> [00002175] 6872210000 push 00002172 ; push DDD >>>> [0000217a] e853f4ffff call 000015d2 ; call HHH(DDD) >>>> [0000217f] 83c404     add esp,+04 >>>> [00002182] 5d         pop ebp >>>> [00002183] c3         ret >>>> Size in bytes:(0018) [00002183] >>>> >>>> DDD specifies that it will continue to call HHH >>>> until HHH sees the repeating pattern and aborts >>>> its simulation. >>>> >>> >>> Yes, they must compute the mapping, but the rules don't say HOW. >> >> *They never bothered to say HOW until NOW* >> The ultimate definition of a correct simulation >> is a simulation according to the definition of >> the simulation language. >> >> One is not free to interpret "push ebp" as "jmp 00002183". >> > > And one is not free to halt the simulation and ignore the halting > behaviour specified in the remainder of the input, because it is against > the rules of the simulation language. _DDD() [00002192] 55 push ebp [00002193] 8bec mov ebp,esp [00002195] 6892210000 push 00002192 [0000219a] e833f4ffff call 000015d2 // call HHH [0000219f] 83c404 add esp,+04 [000021a2] 5d pop ebp [000021a3] c3 ret Size in bytes:(0018) [000021a3] Show me how DDD correctly simulated by HHH reaches its own "ret" instruction. You won't do this because you know that you are a damned liar. -- Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius hits a target no one else can see." Arthur Schopenhauer