Embedding of countable orders in Turing degrees

作     者：Ishmukhametov, ST 

作者机构：Ulyanovsk State Univ Ulyanovsk Russia 

出 版 物：《MATHEMATICAL NOTES》 (数学札记)

年 卷 期：2002年第72卷第5-6期

页      面：631-635页

核心收录：

学科分类：07[理学] 0701[理学-数学] 070101[理学-基础数学] 

基　　金：Russian Foundation for Basic Research  RFBR  (01-01-00733) 

主　　题：recursive function Turing degrees embedding method ordering lattice 

摘      要：In their classical papers, Lerman, Lachlan, and Lebeuf developed the embedding method, which provides constructions of initial segments of Turing degrees isomorphic to various partially ordered structures. We analyze this method and prove that there is a nonzero degree below each decreasing chain of degrees uniform in 0 . This imposes restrictions on the application of the embedding method.