On 1-Degrees Inside m-Degrees

被引:0
作者
Batyrshin, I. I. [1 ]
机构
[1] Kazan Volga Reg Fed Univ, Kazan 420008, Tatarstan, Russia
基金
俄罗斯科学基金会;
关键词
m-degrees; 1-degrees;
D O I
10.1134/S1995080221120076
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
We study the structure of 1-degrees insidem-degrees and prove that every Delta(0)(2) m-degree that has more than one 1-degree contains an infinite antichain of 1-degrees. This strengthens Degtev's result on computably enumerable m-degrees and gives partial answer to the following question stated by Odifreddi: if an m-degree has more than one 1-degree, does it contain an infinite antichain of 1-degrees? The proved result demonstrates that the answer is positive for Delta(0)(2) mdegrees.
引用
收藏
页码:2740 / 2743
页数:4
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