منابع مشابه
Solovay's theorem cannot be simplified
In this paper we consider three potential simplifications to a result of Solovay’s concerning the Turing degrees of nonstandard models of arbitrary completions of first-order Peano Arithmetic (PA). Solovay characterized the degrees of nonstandard models of completions T of PA, showing that they are the degrees of sets X such that there is an enumeration R ≤T X of an “appropriate” Scott set and ...
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SOMMARIO/ABSTRACT Preferences typically define a partial ordering over outcomes. A number of formalisms like soft constraints and CP-nets exists to specify such partial or-derings. In situations involving multiple agents, we need to combine the preferences of several individuals. In this paper, we consider each agent as voting on whether they prefer one outcome to another. We prove that, under ...
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 2001
ISSN: 0168-0072
DOI: 10.1016/s0168-0072(01)00095-1