Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: Andy Walker Newsgroups: comp.theory Subject: Re: Every sufficiently competent C programmer knows --- Semantic Property of Finite String Date: Fri, 14 Mar 2025 23:09:53 +0000 Organization: Not very much Lines: 22 Message-ID: References: <5429f6c8b8a8a79e06b4aeefe677cc54a2a636bf@i2pn2.org> <924e22fc46d629b311b16a954dd0bed980a0a094@i2pn2.org> <0672fec6cb2a5c56fd674bbbb3d2b2101c8f295f@i2pn2.org> <87bju3jswc.fsf@nosuchdomain.example.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Sat, 15 Mar 2025 00:09:54 +0100 (CET) Injection-Info: dont-email.me; posting-host="6e59f8192c6943d3155a73cdc6020c64"; logging-data="2342908"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19PYvkS7lgo4BRhMZNAs6sA" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:RJY7JQbw8dWLq8fYs/wewtGo+rI= In-Reply-To: <87bju3jswc.fsf@nosuchdomain.example.com> Content-Language: en-US Bytes: 2747 On 14/03/2025 19:48, Keith Thompson wrote: > [...] That would imply that [PO] could solve > Goldbach's Conjecture, among other things, but I haven't seen him > do so. Perhaps [just about] worth noting that a sufficiently long [but not "infinite"] brute force attack on the GC [and many other similar conjectures] would resolve the issue. Basically, if you have a program [eg, TM] of size N by some suitable measure [eg, TM states] then within [eg] BB(N) steps it must find the counter-example [if there is one] or else there isn't one [and the GC is proven true], where BB is the Busy Beaver function. Of course, BB is uncomputable, but that doesn't mean specific individual values are uncomputable, just that there is no TM that computes it /in general/. [I have mentioned here before that BB gives us a much less troublesome way of attacking the HP than the standard proofs.] -- Andy Walker, Nottingham. Andy's music pages: www.cuboid.me.uk/andy/Music Composer of the day: www.cuboid.me.uk/andy/Music/Composers/Mayer