Limitations of Efficient Reducibility to the Kolmogorov Random Strings

John M. Hitchcock

Abstract:
We show the following results for polynomial-time reducibility to RC, the set of Kolmogorov random strings.

  1. If P ≠ NP, then SAT does not dtt-reduce to RC.
  2. If PH does not collapse, then SAT does not nα-tt-reduce to RC for any α < 1.
  3. If PH does not collapse, then SAT does not nα-T-reduce to RC for any α < 1/2.
  4. There is a problem in E that does not dtt-reduce to RC.
  5. There is a problem in E that does not nα-tt-reduce to RC for any α < 1.
  6. There is a problem in E that does not nα-T-reduce to RC for any α < 1/2.
These results hold for both the plain and prefix-free variants of Kolmogorov complexity and are also independent of the choice of the universal machine.