Deutsch English Français Italiano |
<v3apb1$1rm2e$2@dont-email.me> View for Bookmarking (what is this?) Look up another Usenet article |
Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: "Fred. Zwarts" <F.Zwarts@HetNet.nl> Newsgroups: comp.theory,sci.logic Subject: Re: D correctly simulated by H cannot possibly halt --- templates and infinite sets --- deciders Date: Thu, 30 May 2024 22:59:12 +0200 Organization: A noiseless patient Spider Lines: 96 Message-ID: <v3apb1$1rm2e$2@dont-email.me> References: <v3501h$lpnh$1@dont-email.me> <v3a3a3$1nupq$1@dont-email.me> <v3a5fc$1o4q1$2@dont-email.me> <v3abb8$1paor$2@dont-email.me> <v3ahqd$1qehj$2@dont-email.me> <v3aie6$1qgep$1@dont-email.me> <v3ak85$1qoma$1@dont-email.me> <v3amp4$1r7kc$1@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Thu, 30 May 2024 22:59:14 +0200 (CEST) Injection-Info: dont-email.me; posting-host="29f4c7a86fd93e3f265abfb22a9f7fbf"; logging-data="1955918"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/H5QkLw3Fv1jzXVxuesPlk" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:1i9eKGKn6WD8DFkkXc6pehTKOZY= Content-Language: en-GB In-Reply-To: <v3amp4$1r7kc$1@dont-email.me> Bytes: 5263 Op 30.mei.2024 om 22:15 schreef olcott: > On 5/30/2024 2:32 PM, Fred. Zwarts wrote: >> Op 30.mei.2024 om 21:01 schreef olcott: >>> On 5/30/2024 1:50 PM, Fred. Zwarts wrote: >>>> Op 30.mei.2024 om 19:00 schreef olcott: >>>>> On 5/30/2024 10:20 AM, Fred. Zwarts wrote: >>>>>> Op 30.mei.2024 om 16:43 schreef olcott: >>>>>>> On 5/28/2024 11:16 AM, olcott wrote: >>>>>>>> >>>>>>>> When Ĥ is applied to ⟨Ĥ⟩ >>>>>>>> Ĥ.q0 ⟨Ĥ⟩ ⊢* embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩ ⊢* Ĥ.qy ∞ >>>>>>>> Ĥ.q0 ⟨Ĥ⟩ ⊢* embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩ ⊢* Ĥ.qn >>>>>>>> >>>>>>>> *Formalizing the Linz Proof structure* >>>>>>>> ∃H ∈ Turing_Machines >>>>>>>> ∀x ∈ Turing_Machines_Descriptions >>>>>>>> ∀y ∈ Finite_Strings >>>>>>>> such that H(x,y) = Halts(x,y) >>>>>>>> >>>>>>> >>>>>>> A decider computes the mapping from finite string inputs to >>>>>>> its own accept or reject state. >>>>>>> >>>>>>> A decider does not and cannot compute the mapping from >>>>>>> Turing_Machine inputs to its own accept or reject state. >>>>>>> >>>>>>> Halts(x,y) would report on the direct execution of x(y) thus ignores >>>>>>> the pathological behavior of x correctly simulated by pure >>>>>>> function H. >>>>>>> This makes Halts(x,y) an incorrect measure of the correctness of >>>>>>> H(x,y). >>>>>> >>>>>> Why are you referring to the 'pathological behavior of x' if your >>>>>> claim is that the simulator does not even reach the part of DD >>>>>> (below) that contradicts the result of HH? This 'pathological >>>>>> behavior of x' is completely irrelevant. >>>>> >>>>> It is totally relevant because it is the reason why D correctly >>>>> simulated by H cannot possibly halt. >>>> >>>> Incorrect. Your own words are that lines 04, 05 and 06 are nor >>>> reachable for the simulator. >>> >>> Because D correctly simulated by H remains stuck in recursive simulation >>> because D calls H(D,D) in recursive simulation D cannot possibly reach >>> past its own line 03. >>> >>> You must must 100% complete attention to the exact words that I >>> exactly say. >>> >> >> If you ask to 100% attention, please, pay also attention to the >> replies and read more than the first few words. You remove most of my >> reply, probably because you did not read them. >> > > I soon as yo show that you are starting with a fundamentally false > assumption I stop reading. > >> The fact that D does not reach past line 03, means that lines 04, 05 >> and 06 do not play a role in the decision. > > OK > >> Do you understand C? > > I learned C back when K&R was the standard and have been a professional > C++ software engineer for two decades. I have been professional > programmer since 1984. > >> If line 04 cannot be reached, lines 05 and 06 do not cause any >> behaviour. In particular no 'pathological' behaviour. >> > > The reason why these lines can't be reached is that D calls H(D,D) > in recursive simulation. This relationship between H and D is > typically called pathological. > >> It is H that keeps repeating the simulation of D > > D calls H(D,D) in recursive simulation until H stops this. > THIS IS D'S FAULT! Shouting does not make it true! It shows a lack of reasoning. This is a fundamentally false assumption, so I stop reading here. It is not D's fault. It is H's choice to start the simulation, not D's. D does not even know of simulation at all. D is assumed to call a decider that is required to halt, so it is H's task to halt the decision process, not D's. But H fails to halt: H keeps simulating H in recursive simulation, but if the simulation of H would halt (that is a requirement), then D would continue with line 04. Every competent C programmer can see that. But the simulation of H violates that requirement. The fact that H gets stuck in recursive simulation is inherent to a simulating halt decider. That makes a simulating halt decider a bad idea.