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This is an old revision of this page, as edited by Hermel (talk | contribs) at 22:17, 28 December 2019 (Flaw in proof?: new section). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
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In the note on step 3: " Execution is limited to 2^f(|x|) steps in order to avoid the case where M does not halt on the input x... That is, the case where M consumes space of only O(f(x)) as required, but runs for infinite time. "

If M does not halt on input x it does not accept x. The algorithm for deciding L should therefore accept in case more than 2^f(|x|) were made, as M does not accept <M>,10^k, and <M>,10^k is therefore in L, from the definition. —Preceding unsigned comment added by 132.74.99.86 (talk) 06:31, 1 March 2009 (UTC)[reply]

Flaw in proof?

At cs.SE the proof as given in this article is discussed, and some parts seem to be incorrect or incomplete according to the discussion. Please improve if you are knowledgeable about the subject. https://cs.stackexchange.com/questions/104982/proof-of-space-hierarchy-theorem-incompatible-with-linear-speed-up-theorem-for-t/105282 Hermel (talk) 22:17, 28 December 2019 (UTC)[reply]