Our server costs ~$56 per month to run. Please consider donating or becoming a Patron to help keep the site running. Help us gain new members by following us on Twitter and liking our page on Facebook!
Current time: May 20, 2024, 12:56 pm

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Oracles and the Halting Problem
#15
RE: Oracles and the Halting Problem
(November 28, 2012 at 4:09 am)CliveStaples Wrote:
(November 27, 2012 at 9:53 pm)apophenia Wrote: In order for the list to be searched, it must first exist. The list may be generated algorithmically or non-algorithmically. The halting problem says the list cannot be generated algorithmically. Therefore, for the list to be generated, it has to be generated non-algorithmically, which removes it from the purview of the halting problem.

It does? Where?
The list you mentioned was one that God had which had every possible algorithm on it, and whether or not it halted. Such a list is cannot be generated (nor can it even exist) since it would violate the entire proof that Alan Turing set about in 1936:

"Alan Turing proved in 1936 that a general algorithm to solve the halting problem for all possible program-input pairs cannot exist."

If such a list could exist, then as you said before, there would be an algorithm for determining whether any given program halted (simply search the list until you find the algorithm). However, this determination algorithm would clearly meet the criteria for being the general algorithm that Alan Turing proved cannot exist. Therefore, the list cannot exist either (since all lists are searchable).
Reply



Messages In This Thread
Oracles and the Halting Problem - by CliveStaples - November 27, 2012 at 9:01 am
RE: Oracles and the Halting Problem - by Tiberius - November 27, 2012 at 9:20 am
RE: Oracles and the Halting Problem - by CliveStaples - November 27, 2012 at 11:20 am
RE: Oracles and the Halting Problem - by Tiberius - November 27, 2012 at 3:27 pm
RE: Oracles and the Halting Problem - by CliveStaples - November 27, 2012 at 3:34 pm
RE: Oracles and the Halting Problem - by Anomalocaris - November 27, 2012 at 11:27 am
RE: Oracles and the Halting Problem - by CliveStaples - November 27, 2012 at 11:50 am
RE: Oracles and the Halting Problem - by Angrboda - November 27, 2012 at 2:29 pm
RE: Oracles and the Halting Problem - by CliveStaples - November 27, 2012 at 3:11 pm
RE: Oracles and the Halting Problem - by Tiberius - November 27, 2012 at 3:58 pm
RE: Oracles and the Halting Problem - by Angrboda - November 27, 2012 at 9:53 pm
RE: Oracles and the Halting Problem - by jonb - November 27, 2012 at 10:44 pm
RE: Oracles and the Halting Problem - by CliveStaples - November 28, 2012 at 4:09 am
RE: Oracles and the Halting Problem - by jonb - November 28, 2012 at 7:24 am
RE: Oracles and the Halting Problem - by Tiberius - November 28, 2012 at 7:49 pm



Users browsing this thread: 1 Guest(s)