The uniform Martin's conjecture for many-one degrees

Abstract

We study functions from reals to reals which are uniformly degree-invariant from Turing-equivalence to many-one equivalence, and compare them "on a cone." We prove that they are in one-to-one correspondence with the Wadge degrees, which can be viewed as a refinement of the uniform Martin's conjecture for uniformly invariant functions from Turing- to Turing-equivalence. Our proof works in the general case of many-one degrees on ${\mathcal{Q}}^{\omega }$ and Wadge degrees of functions ${\omega }^{\omega }\to \mathcal{Q}$ for any better quasi ordering $\mathcal{Q}$.