3 papers
math.LO2024
Finite final segments of the d.c.e. Turing degrees
Steffen Lempp, Yiqun Liu, Yong Liu +3
We prove that every finite distributive lattice is isomorphic to a final segment of the d.c.e. Turing degrees (i.e., the degrees of differences of computably enumerable sets). As a…
math.LO2022
Limit Complexities, Minimal Descriptions, and -Randomness
Rodney Downey, Lu Liu, Keng Meng Ng +1
Let denote prefix-free Kolmogorov Complexity, and denote it relative to an oracle . We show that for any , is definable purely in terms of the…
math.LO2014
An analogy between cardinal characteristics and highness properties of oracles
Jörg Brendle, Andrew Brooke-Taylor, Keng Meng Ng +1
We present an analogy between cardinal characteristics from set theory and highness properties from computability theory, which specify a sense in which a Turing oracle is computat…