the complexity barrier
Dave Long <[email protected]>
| Newsgroups | gmane.culture.people.kragen.discuss |
|---|---|
| Message-ID | <[email protected]> |
http://johncarlosbaez.wordpress.com/2011/10/28/the-complexity-barrier/ > ...here’s a more interesting question: how complex can we prove > something to be? > The answer is one of the most astounding facts I know. It’s called > Chaitin’s incompleteness theorem. It says, very roughly: > >> There’s a number L such that we can’t prove the Kolmogorov >> complexity of any specific string of bits is bigger than L. >> >> > > Make sure you understand this. For any number, we can prove there > are infinitely many bit strings with Kolmogorov complexity bigger > than that. But we can’t point to any particular bit string and > prove its Kolmogorov complexity is bigger than L! > > Over on Google+, Allen Knutson wrote: > >> That’s an incredibly disturbing theorem, like driving to the edge >> of the universe and finding a wall. >> >> > > I call L the complexity barrier. So one question is, how big is L? > It’s hard, or perhaps even impossible, to find the smallest L that > does the job. But we can certainly find numbers L that work. And > they’re surprisingly small! > > My friend Bruce estimates that the complexity barrier is a few > kilobytes. > -- To unsubscribe: http://lists.canonical.org/mailman/listinfo/kragen-discuss