Warning: mysqli::__construct(): (HY000/1203): User howardkn already has more than 'max_user_connections' active connections in D:\Inetpub\vhosts\howardknight.net\al.howardknight.net\includes\artfuncs.php on line 21
Failed to connect to MySQL: (1203) User howardkn already has more than 'max_user_connections' active connectionsPath: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: olcott Newsgroups: comp.theory Subject: Re: Halting Problem: What Constitutes Pathological Input Date: Mon, 5 May 2025 17:27:31 -0500 Organization: A noiseless patient Spider Lines: 76 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Tue, 06 May 2025 00:27:31 +0200 (CEST) Injection-Info: dont-email.me; posting-host="4d3877b25e07ae675aebb853b858fd37"; logging-data="1408292"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19+SwnP0REsXj3uUHvMe1bM" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:K/1NuaRhy3k6n5kpl4v1Ot3G9VU= In-Reply-To: X-Antivirus-Status: Clean Content-Language: en-US X-Antivirus: Norton (VPS 250505-6, 5/5/2025), Outbound message On 5/5/2025 4:58 PM, dbush wrote: > On 5/5/2025 5:39 PM, olcott wrote: >> On 5/5/2025 4:31 PM, dbush wrote: >>> On 5/5/2025 5:08 PM, olcott wrote: >>>> On 5/5/2025 3:14 PM, dbush wrote: >>>>> On 5/5/2025 4:10 PM, olcott wrote: >>>>>> On 5/5/2025 3:00 PM, dbush wrote: >>>>>>> On 5/5/2025 3:54 PM, olcott wrote: >>>>>>>> On 5/5/2025 2:49 PM, dbush wrote: >>>>>>>>> On 5/5/2025 3:38 PM, olcott wrote: >>>>>>>>>> On 5/5/2025 2:23 PM, Richard Heathfield wrote: >>>>>>>>>>> On 05/05/2025 20:20, olcott wrote: >>>>>>>>>>>> Is "halts" the correct answer for H to return?  NO >>>>>>>>>>>> Is "does not halt" the correct answer for H to return?  NO >>>>>>>>>>>> Both Boolean return values are the wrong answer >>>>>>>>>>> >>>>>>>>>>> Or to put it another way, the answer is undecidable, QED. >>>>>>>>>>> >>>>>>>>>>> See? You got there in the end. >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Is this sentence true or false: "What time is it?" >>>>>>>>>> is also "undecidable" because it is not a proposition >>>>>>>>>> having a truth value. >>>>>>>>>> >>>>>>>>>> Is this sentence true or false: "This sentence is untrue." >>>>>>>>>> is also "undecidable" because it is not a semantically sound >>>>>>>>>> proposition having a truth value. >>>>>>>>>> >>>>>>>>>> Can Carol correctly answer “no” to this (yes/no) question? >>>>>>>>>> >>>>>>>>>> Both Yes and No are the wrong answer proving that >>>>>>>>>> the question is incorrect when the context of who >>>>>>>>>> is asked is understood to be a linguistically required >>>>>>>>>> aspect of the full meaning of the question. >>>>>>>>> >>>>>>>>> And "does algorthm X with input Y halt when executed directly" >>>>>>>>> has a single well defined answer. >>>>>>>>> >>>>>>>> >>>>>>>> That is not even the actual question. >>>>>>>> >>>>>>> >>>>>>> In other words, you don't understand what the halting problem is >>>>>>> about, because that is EXACTLY the question. >>>>>>> >>>>>> >>>>>> That question is in many textbooks yet is still >>>>>> wrong because functions computed by models of >>>>>> computation such as Turing Machines or RASP machines >>>>>> are only allowed to use actual inputs as their basis. >>>>> >>>>> And no Turing machine can compute the following mapping, as proven >>>>> by Linz and other and as you have *explicitly* agreed is correct. >>>>> >>>> >>>> No TM can compute the square root of a dead rabbit either. >>> >>> Strawman.  The square root of a dead rabbit does not exist, but the >>> question of whether any arbitrary algorithm X with input Y halts when >>> executed directly has a correct answer in all cases. >>> >> >> It has a correct answer that cannot ever be computed > Excellent!  So you once again *explicitly* agree that the theorem that > the halting problem proofs prove is correct. > because no Turing Machine can take the direct execution of another Turing Machine as an input. Likewise the square root of a dead rabbit cannot be computed. -- Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius hits a target no one else can see." Arthur Schopenhauer