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: Simulation vs. Execution in the Halting Problem Date: Mon, 2 Jun 2025 09:36:53 -0500 Organization: A noiseless patient Spider Lines: 78 Message-ID: <101kcu5$3bfvj$1@dont-email.me> References: <101a7uv$3vfam$5@dont-email.me> <101br7m$db03$1@dont-email.me> <101cjk7$hfof$7@dont-email.me> <101hdjt$21ui2$1@dont-email.me> <101iheg$2h3fr$1@dont-email.me> <1e5e5837ae9e60daa16e5fef3693ff424c1049d2@i2pn2.org> <101j60c$2urhr$3@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Mon, 02 Jun 2025 16:36:55 +0200 (CEST) Injection-Info: dont-email.me; posting-host="01672d8ae9aa1e0fec727857b1cb5419"; logging-data="3522547"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/PDL6n1mElwPT19JwdVhAQ" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:IUOOPhDyPWKwNwiO8avZgvCIhAA= In-Reply-To: Content-Language: en-US X-Antivirus-Status: Clean X-Antivirus: Norton (VPS 250602-4, 6/2/2025), Outbound message Bytes: 4244 On 6/2/2025 6:13 AM, Richard Damon wrote: > On 6/1/25 11:32 PM, olcott wrote: >> On 6/1/2025 8:19 PM, Richard Damon wrote: >>> On 6/1/25 5:41 PM, olcott wrote: >>>> On 6/1/2025 6:30 AM, Mikko wrote: >>>>> On 2025-05-30 15:41:59 +0000, olcott said: >>>>> >>>>>> On 5/30/2025 3:45 AM, Mikko wrote: >>>>>>> On 2025-05-29 18:10:39 +0000, olcott said: >>>>>>> >>>>>>>> On 5/29/2025 12:34 PM, Mr Flibble wrote: >>>>>>>>> >>>>>>>>> 🧠 Simulation vs. Execution in the Halting Problem >>>>>>>>> >>>>>>>>> In the classical framework of computation theory (Turing >>>>>>>>> machines), >>>>>>>>> simulation is not equivalent to execution, though they can >>>>>>>>> approximate one >>>>>>>>> another. >>>>>>>> >>>>>>>> To the best of my knowledge a simulated input >>>>>>>> always has the exact same behavior as the directly >>>>>>>> executed input unless this simulated input calls >>>>>>>> its own simulator. >>>>>>> >>>>>>> The simulation of the behaviour should be equivalent to the real >>>>>>> behaviour. >>>>>> >>>>>> That is the same as saying a function with infinite >>>>>> recursion must have the same behavior as a function >>>>>> without infinite recursion. >>>>> >>>>> A function does not have a behaviour. A function has a value for >>>>> every argument in its domain. >>>>> >>>>> A function is not recursive. A definition of a function can be >>>>> recursive. There may be another way to define the same function >>>>> without recursion. >>>>> >>>>> A definition of a function may use infinite recursion if it is also >>>>> defined how that infinite recursion defines a value. >>>>> >>>>> Anyway, from the meaning of "simulation" follows that a simulation >>>>> of a behaviour is (at least in some sense) similar to the real >>>>> behaviour. Otherwise no simulation has happened. >>>>> >>>> >>>> void DDD() >>>> { >>>>    HHH(DDD); >>>>    return; >>>> } >>>> >>>> The *input* to simulating termination analyzer HHH(DDD) >>>> specifies recursive simulation that can never reach its >>>> *simulated "return" instruction final halt state* >>>> >>>> *Every rebuttal to this changes the words* >>>> >>> >>> No it doesn't, as HHH is defined to abort and simulation after finite >>> time, and thus only does finite simulation. >>> >> >> See right there you changed the words. >> I said nothing about finite or infinite simulation. >> You said that I am wrong about something that I didn't even say. >> > > But you mean infinitly recursive, or you have no evidence of non-halting. > That is not the way that the computer science works. Can't possibly reach final halt state *is* non-halting. -- Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius hits a target no one else can see." Arthur Schopenhauer