Path: ...!weretis.net!feeder8.news.weretis.net!news.szaf.org!news.karotte.org!news.space.net!news.muc.de!.POSTED.news.muc.de!not-for-mail From: Alan Mackenzie Newsgroups: comp.theory Subject: Re: Can D simulated by H terminate normally? Date: Mon, 29 Apr 2024 16:17:52 -0000 (UTC) Organization: muc.de e.V. Message-ID: References: Injection-Date: Mon, 29 Apr 2024 16:17:52 -0000 (UTC) Injection-Info: news.muc.de; posting-host="news.muc.de:2001:608:1000::2"; logging-data="57451"; mail-complaints-to="news-admin@muc.de" User-Agent: tin/2.6.3-20231224 ("Banff") (FreeBSD/14.0-RELEASE-p5 (amd64)) Bytes: 4977 Lines: 108 olcott wrote: > On 4/29/2024 10:23 AM, Alan Mackenzie wrote: >> olcott wrote: >>> On 4/29/2024 9:37 AM, Alan Mackenzie wrote: >>>> In comp.theory olcott wrote: >>>>> On 4/28/2024 1:39 PM, Richard Damon wrote: >>>>>> On 4/28/24 2:19 PM, olcott wrote: >>>> [ .... ] >>>>>>> Even the term "halting" is problematic. >>>>>>> For 15 years I thought it means stops running for any reason. >> [ .... ] >>>> Having been aborted (if such were possible) is merely another final >>>> state for a TM. >>> No it definitely is not. >> In a TM, each state is either a final state or a non-final state. Are >> you arguing for a third alternative, or do you think that "having been >> aborted" is a non-final state? If the latter, what state does the TM >> change to next? > Aborted means completely dead as if you pulled the power cord > on your computer. A turing machine has no power cord to pull. You didn't answer my point; you evaded it. >>> When the payroll system crashes 10% of the way through calculating >>> payroll we cannot say that everyone has been paid. >> Of course not, but it has nevertheless reached a final state, an >> unsatisfactory one, since it is no longer running on the computer. > That is not what "theory of computation" {final state} means. I think it is. What do you think "final state" means, and how is "having been aborted" not one? > Core dump abnormal termination does not count as the program > correctly finished its processing. There is no notion of "correct" in a turing machine. It is either running, or has reached a final state. In the TM equivalent of "core dump", a final state has most definitely been reached. >>>>> Yet again only rhetoric with no actual reasoning. >>>>> Do you believe: >>>>> (a) Halting means stopping for any reason. >>>>> (b) Halting means reaching a final state. >>>> (a) and (b) are identical. A TM having stopped means it has reached a >>>> final state, and vice versa. >>> No that is incorrect. >> Perhaps, then, you could explain the difference between (a) and (b). No answer? >>> In software engineering terms halting means reaching a final >>> state and terminating normally. >> "Halting" is about turing machines. > Yet any C function that implements a computable function is > isomorphic to some TM. Yes. There is no such thing as a core dump in a computable function. >> I don't think you've ever said what you mean by "terminating >> normally". > Standard term of the art from software engineering. That's an evasion, not an answer. We're talking about the theory of turnig machines here. What do _you_ mean for a turing machine to terminate "normally"? I put it to you it has no meaning at all. >> A turing machine either reaches a final state or it doesn't. There is >> no concept of "normal termination" in a TM. No answer? > A Google search of: "simulating termination analyzer" > or "simulating halt decider" only brings up me. That surprises nobody. There's no such thing as a halt decider, simulating or otherwise. As for a "termination analyzer", I don't think you've ever made clear what you mean by this. > Within this brand new idea then there is such an idea of > abnormal termination. It's not a brand new idea. Just ask those who teach the theory, and they'll tell you that this idea comes up continually, year after year. And at the risk of repeating myself, there is no notion of "abnormal termination" on a turing machine. > -- > Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius > hits a target no one else can see." Arthur Schopenhauer -- Alan Mackenzie (Nuremberg, Germany).