We consider the notion of mass problem of presentability for countable structures, and study the relationship between Medvedev and Muchnik reducibilities on such problems and possible ways of syntactically characterizing these reducibilities. Also, we consider the notions of strong and weak presentability dimension and characterize classes of structures with presentability dimensions 1.


Open Interval Atomic Formula Recursive Operator Mass Problem Countable Structure 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Alexey Stukachev
    • 1
  1. 1.Sobolev Institute of MathematicsNovosibirskRussia

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