Automorphisms of the lattice of \(\Pi_1^0\) classes; perfect thin classes and anc degrees (Q2750927)

From MaRDI portal





scientific article; zbMATH DE number 1663170
Language Label Description Also known as
English
Automorphisms of the lattice of \(\Pi_1^0\) classes; perfect thin classes and anc degrees
scientific article; zbMATH DE number 1663170

    Statements

    0 references
    0 references
    0 references
    0 references
    21 October 2001
    0 references
    thin class
    0 references
    automorphisms
    0 references
    invariance
    0 references
    Automorphisms of the lattice of \(\Pi_1^0\) classes; perfect thin classes and anc degrees (English)
    0 references
    The paper is devoted to the study of the lattice of \(\Pi_{1}^{0}\) classes. It focuses on the analog of maximality, or, more precisely, hyperhypersimplicity, namely the notion of a thin class. A number of results relating automorphisms, invariance and thin classes is proved. The main results are an analog of Martin's work on hyperhypersimple sets and high degrees and an analog of Soare's work demonstrating that maximal sets form an orbit.
    0 references

    Identifiers