A minimal set low for speed
Abstract
An oracle is low-for-speed if it is unable to speed up the computation of a set which is already computable: if a decidable language can be decided in time using as an oracle, then it can be decided without an oracle in time for some polynomial . The existence of a set which is low-for-speed was first shown by Bayer and Slaman who constructed a non-computable computably enumerable set which is low-for-speed. In this paper we answer a question previously raised by Bienvenu and Downey, who asked whether there is a minimal degree which is low-for-speed. The standard method of constructing a set of minimal degree via forcing is incompatible with making the set low-for-speed; but we are able to use an interesting new combination of forcing and full approximation to construct a set which is both of minimal degree and low-for-speed.
Cite
@article{arxiv.2011.09174,
title = {A minimal set low for speed},
author = {Rod Downey and Matthew Harrison-Trainor},
journal= {arXiv preprint arXiv:2011.09174},
year = {2020}
}