Path: ...!2.eu.feeder.erje.net!3.eu.feeder.erje.net!feeder.erje.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: olcott Newsgroups: comp.theory Subject: Re: V5 --- Professor Sipser Date: Sat, 24 Aug 2024 08:24:35 -0500 Organization: A noiseless patient Spider Lines: 72 Message-ID: References: <431deaa157cdae1cae73a1b24268a61cf8ec2c1c@i2pn2.org> <7a1c569a699e79bfa146affbbae3eac7b91cd263@i2pn2.org> <729cc551062c13875686d266a5453a488058e81c@i2pn2.org> <148bf4dd91f32379a6d81a621fb7ec3fc1e00db0@i2pn2.org> <5591ff08ed8f7b4bdf33813681e156b775efe0ec@i2pn2.org> <878qwn0wyz.fsf@bsb.me.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sat, 24 Aug 2024 15:24:36 +0200 (CEST) Injection-Info: dont-email.me; posting-host="9ef66ad74e187b44c1830ef5229db641"; logging-data="1480109"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+S1BVifo2VGyUt+BzdhCWN" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:FdeCG1bm29riJbYOtAORAVQRF24= In-Reply-To: Content-Language: en-US Bytes: 5117 On 8/24/2024 5:16 AM, Mikko wrote: > On 2024-08-24 01:10:49 +0000, Mike Terry said: > >> On 23/08/2024 22:07, Ben Bacarisse wrote: >>> joes writes: >>> >>>> Am Wed, 21 Aug 2024 20:55:52 -0500 schrieb olcott: >>> >>>>> Professor Sipser clearly agreed that an H that does a finite >>>>> simulation >>>>> of D is to predict the behavior of an unlimited simulation of D. >>>> >>>> If the simulator *itself* would not abort. The H called by D is, >>>> by construction, the same and *does* abort. >>> >>> We don't really know what context Sipser was given.  I got in touch at >>> the time so do I know he had enough context to know that PO's ideas were >>> "wacky" and that had agreed to what he considered a "minor remark". >>> >>> Since PO considers his words finely crafted and key to his so-called >>> work I think it's clear that Sipser did not take the "minor remark" he >>> agreed to to mean what PO takes it to mean!  My own take if that he >>> (Sipser) read it as a general remark about how to determine some cases, >>> i.e. that D names an input that H can partially simulate to determine >>> it's halting or otherwise.  We all know or could construct some such >>> cases. >> >> Exactly my reading.  It makes Sipser's agreement natural, because it >> is both correct [with sensible interpretation of terms], and moreover >> describes an obvious strategy that a partial decider might use that >> can decide halting for some specific cases.  No need for Sipser to be >> deceptive or misleading here, when the truth suffices.  (In particular >> no need to employ "tricksy" vacuous truth get out clauses just to get >> PO off his back as some have suggested.) >> >> So that PO will have no cause to quote me as supporting his case: >> what Sipser understood he was agreeing to was NOT what PO interprets >> it as meaning.  Sipser would not agree that the conclusion applies in >> PO's HHH(DDD) scenario, where DDD halts. > > An important part of the agreement is "H correctly determines" which > does not happen in HHH(DDD). > If simulating halt decider H correctly simulates its input D until H correctly determines that its simulated D would never stop running unless aborted then H can abort its simulation of D and correctly report that D specifies a non-halting sequence of configurations. int DD() { int Halt_Status = HHH(DD); if (Halt_Status) HERE: goto HERE; return Halt_Status; } On 10/14/2022 7:44 PM, Ben Bacarisse wrote: > I don't think that is the shell game. PO really /has/ an H > (it's trivial to do for this one case) that correctly determines > that P(P) *would* never stop running *unless* aborted. .... > But H determines (correctly) that D would not halt if it > were not halted. That much is a truism. -- Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius hits a target no one else can see." Arthur Schopenhauer