A hierarchy of Turing degrees : a transfinite hierarchy of lowness notions in the computably enumerable degrees, unifying classes, and natural definability /
Rod Downey, Noam Greenberg.
- 1 online resource : illustrations
- Annals of Mathematics Studies ; v. 385 Annals of mathematics studies ; number 206 .
- Annals of mathematics studies ; no. 206, 385. .
Series: Annals of Mathematics Studies, 385--online resource web page. Annals of Mathematics Studies Number 206--PDF title page
Includes bibliographical references
Computability theory is a branch of mathematical logic and computer science that has become increasingly relevant in recent years. The field has developed growing connections in diverse areas of mathematics, with applications in topology, group theory, and other subfields. This book introduces a new hierarchy that allows them to classify the combinatorics of constructions from many areas of computability theory, including algorithmic randomness, Turing degrees, effectively closed sets, and effective structure theory. This unifying hierarchy gives rise to new natural definability results for Turing degree classes, demonstrating how dynamic constructions become reflected in definability. The book presents numerous construction techniques involving high-level nonuniform arguments, and their self-contained work is appropriate for graduate students and researchers. Blending traditional and modern research results in computability theory, the book establishes novel directions in the field.