Talk:1266: Halting Problem - Revision history

172.69.138.46: Explained fallacy in proof sketch

2019-03-10T22:24:05Z

Explained fallacy in proof sketch

Davidy22 at 02:06, 14 June 2016

2016-06-14T02:06:29Z

162.158.145.84 at 22:13, 13 June 2016

2016-06-13T22:13:16Z

Davidy22 at 23:24, 11 March 2015

2015-03-11T23:24:02Z

108.162.229.53 at 13:43, 11 March 2015

2015-03-11T13:43:06Z

108.162.219.58 at 23:04, 4 February 2014

2014-02-04T23:04:22Z

Bonob at 19:05, 18 October 2013

2013-10-18T19:05:23Z

Bonob at 19:04, 18 October 2013

2013-10-18T19:04:20Z

Bonob at 19:01, 18 October 2013

2013-10-18T19:01:39Z

Xhfz at 17:55, 18 October 2013

2013-10-18T17:55:38Z

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 Machine B determines if Y halts. And Y halts if machine X does not halt. If we had Turing machine A then we could build B.
 [[User:Xhfz|Xhfz]] ([[User talk:Xhfz|talk]]) 17:53, 18 October 2013 (UTC)
 ; Karl Popper

← Older revision		Revision as of 02:06, 14 June 2016
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	The explanation's "1/3 + 1/3 + 1/3 = 1" example ticks me off: symbolic math programs can already give the correct answer to this easily. See http://www.sympygamma.com/input/?i=1%2F3+%2B+1%2F3+%2B+1%2F3 . {{unsigned ip\|108.162.229.53}}		The explanation's "1/3 + 1/3 + 1/3 = 1" example ticks me off: symbolic math programs can already give the correct answer to this easily. See http://www.sympygamma.com/input/?i=1%2F3+%2B+1%2F3+%2B+1%2F3 . {{unsigned ip\|108.162.229.53}}

−	:You're misunderstanding it. "1/3 + 1/3 + 1/3 = 1". You won't -always- get 1 using every implementation. But the answer is always 1. What a computer outputs and what the truth is are not -always- the same thing. It wasn't implied that they are -never- the same thing. It's only a bad example if you always get "1/3 + 1/3 + 1/3 = 1".	+	:You're misunderstanding it. "1/3 + 1/3 + 1/3 = 1". You won't -always- get 1 using every implementation. But the answer is always 1. What a computer outputs and what the truth is are not -always- the same thing. It wasn't implied that they are -never- the same thing. It's only a bad example if you always get "1/3 + 1/3 + 1/3 = 1". {{unsigned ip\|162.158.145.84}}

← Older revision		Revision as of 22:13, 13 June 2016
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	The explanation's "1/3 + 1/3 + 1/3 = 1" example ticks me off: symbolic math programs can already give the correct answer to this easily. See http://www.sympygamma.com/input/?i=1%2F3+%2B+1%2F3+%2B+1%2F3 . {{unsigned ip\|108.162.229.53}}		The explanation's "1/3 + 1/3 + 1/3 = 1" example ticks me off: symbolic math programs can already give the correct answer to this easily. See http://www.sympygamma.com/input/?i=1%2F3+%2B+1%2F3+%2B+1%2F3 . {{unsigned ip\|108.162.229.53}}
		+
		+	:You're misunderstanding it. "1/3 + 1/3 + 1/3 = 1". You won't -always- get 1 using every implementation. But the answer is always 1. What a computer outputs and what the truth is are not -always- the same thing. It wasn't implied that they are -never- the same thing. It's only a bad example if you always get "1/3 + 1/3 + 1/3 = 1".

← Older revision		Revision as of 23:24, 11 March 2015
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	;Bad example for showing the difference between theoretical computation and "actual" computation		;Bad example for showing the difference between theoretical computation and "actual" computation

−	The explanation's "1/3 + 1/3 + 1/3 = 1" example ticks me off: symbolic math programs can already give the correct answer to this easily. See http://www.sympygamma.com/input/?i=1%2F3+%2B+1%2F3+%2B+1%2F3 .	+	The explanation's "1/3 + 1/3 + 1/3 = 1" example ticks me off: symbolic math programs can already give the correct answer to this easily. See http://www.sympygamma.com/input/?i=1%2F3+%2B+1%2F3+%2B+1%2F3 . {{unsigned ip\|108.162.229.53}}

← Older revision		Revision as of 13:43, 11 March 2015
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	I think that the title text is a direct reference to Karl Popper's falsifiability argument, since this is one of the most common example of a non-falsifiable statement. [[User:Bonob\|Bonob]] ([[User talk:Bonob\|talk]]) 19:01, 18 October 2013 (UTC)		I think that the title text is a direct reference to Karl Popper's falsifiability argument, since this is one of the most common example of a non-falsifiable statement. [[User:Bonob\|Bonob]] ([[User talk:Bonob\|talk]]) 19:01, 18 October 2013 (UTC)
	:Popper claimed that such things are outside the realms of science, correct? The undecidability of this question has been used to falsify other intended scientific proofs. Therefore, it is surely within the realms of science. [[Special:Contributions/108.162.219.58\|108.162.219.58]] 23:04, 4 February 2014 (UTC)		:Popper claimed that such things are outside the realms of science, correct? The undecidability of this question has been used to falsify other intended scientific proofs. Therefore, it is surely within the realms of science. [[Special:Contributions/108.162.219.58\|108.162.219.58]] 23:04, 4 February 2014 (UTC)
		+
		+	;Bad example for showing the difference between theoretical computation and "actual" computation
		+
		+	The explanation's "1/3 + 1/3 + 1/3 = 1" example ticks me off: symbolic math programs can already give the correct answer to this easily. See http://www.sympygamma.com/input/?i=1%2F3+%2B+1%2F3+%2B+1%2F3 .

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 What is the joke here? What does "big picture" mean? [[Special:Contributions/62.209.198.2|62.209.198.2]] 16:33, 18 September 2013 (UTC)
 :I believe it's related to the quote " In the long run we are all dead." by John Maynard Keynes. [[User:Osias|Osias]] ([[User talk:Osias|talk]]) 18:46, 18 September 2013 (UTC)
 Same kind of humor as in http://www.explainxkcd.com/wiki/index.php?title=221 [[Special:Contributions/176.67.13.14|176.67.13.14]] 18:47, 18 September 2013 (UTC)
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 : It won't work if your program is exit() or shutdownYourComputer(). :) --[[Special:Contributions/61.223.87.164|61.223.87.164]] 00:49, 28 September 2013 (UTC)
 ::It will. We are talking about Turing machines. A Turing machine can stop itself, but it cannot stop the calling Turing machine.  [[User:Xhfz|Xhfz]] ([[User talk:Xhfz|talk]]) 12:43, 7 October 2013 (UTC)
 :::Turing machines are known to be really poor at I/O. If you trace the shutdownYourComputer function, it actually instructs your {{w|Power_supply_unit_(computer)|power supply unit}} (ATX required, AT lacked such capability) to turn power down. Similarly, rebootYourComputer function instruct outside hardware - usually {{w|Northbridge_(computing)|north bridge}} - to send a reset signal on the {{w|Peripheral_Component_Interconnect|PCI bus}} (and presumably other busses), which will reset all devices and start {{w|Power-on_self-test|POST}}. Unlike Turing machines, virtualized OSs may be able to reboot host computer if the hypervisor is not coded correctly and allows I/O for hardware acceleration. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 09:22, 16 October 2013 (UTC)
 ; The halting problem for every input
 The sentence in bold is false
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 ; Karl Popper
 I think that the title text is a direct reference to Karl Popper's falsifiability argument, since this is one of the most common example of a non-falsifiable statement. [[User:Bonob|Bonob]] ([[User talk:Bonob|talk]]) 19:01, 18 October 2013 (UTC)

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	[[User:Xhfz\|Xhfz]] ([[User talk:Xhfz\|talk]]) 17:53, 18 October 2013 (UTC)		[[User:Xhfz\|Xhfz]] ([[User talk:Xhfz\|talk]]) 17:53, 18 October 2013 (UTC)

−	I think that the title text is a direct reference to Karl Popper's falsifiability argument, since this is the most common example of a non-falsifiable statement.[[User:Bonob\|Bonob]] ([[User talk:Bonob\|talk]]) 19:01, 18 October 2013 (UTC)	+
		+	; Karl Popper
		+	I think that the title text is a direct reference to Karl Popper's falsifiability argument, since this is one of the most common example of a non-falsifiable statement.[[User:Bonob\|Bonob]] ([[User talk:Bonob\|talk]]) 19:01, 18 October 2013 (UTC)

← Older revision		Revision as of 19:01, 18 October 2013
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	Machine B determines if Y halts. And Y halts if machine X does not halt. If we had Turing machine A then we could build B.		Machine B determines if Y halts. And Y halts if machine X does not halt. If we had Turing machine A then we could build B.
	[[User:Xhfz\|Xhfz]] ([[User talk:Xhfz\|talk]]) 17:53, 18 October 2013 (UTC)		[[User:Xhfz\|Xhfz]] ([[User talk:Xhfz\|talk]]) 17:53, 18 October 2013 (UTC)
		+
		+	I think that the title text is a direct reference to Karl Popper's falsifiability argument, since this is the most common example of a non-falsifiable statement.[[User:Bonob\|Bonob]] ([[User talk:Bonob\|talk]]) 19:01, 18 October 2013 (UTC)

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 The function next returns the next valid string. For example, if our alphabet is A..Z0..9, then next("AJ38YT") = "AJ38YU"
-Machine B determines if Y halts. And Y halts if machine X does not halt. If we had Turing machine A the we could build B.
+Machine B determines if Y halts. And Y halts if machine X does not halt. If we had Turing machine A then we could build B.
 [[User:Xhfz|Xhfz]] ([[User talk:Xhfz|talk]]) 17:53, 18 October 2013 (UTC)