The computable Lipschitz degrees of computably enumerable sets are not dense

The computable Lipschitz reducibility was introduced by Downey, Hirschfeldt and LaForte under the name of strong weak truthtable reducibility [6]. This reducibility measures both the relative randomness and the relative computational power of real numbers. This paper proves that the computable Lipschitz degrees of computably enumerable sets are not dense. An immediate corollary is that the Solovay degrees of strongly c.e. reals are not dense. There are similarities to Barmpalias and Lewis's proof that the identity bounded Turing degrees of c.e. sets are not dense [2], however the problem for the computable Lipschitz degrees is more complex.

• Type: Journal
• Year: 2010
• Where: APAL
• Authors: Adam R. Day
• Keywords: APAL 2010, Computable Lipschitz, Computable Lipschitz Degrees, Computable Lipschitz Reducibility