منابع مشابه
s-Degrees within e-Degrees
For any enumeration degree a let D a be the set of s-degrees contained in a. We answer an open question of Watson by showing that if a is a nontrivial Σ2-enumeration degree, then D a has no least element. We also show that every countable partial order embeds into D a.
متن کاملI classes, LR degrees and Turing degrees
We say that A ≤LR B if every B-random set is A-random with respect to Martin-Löf randomness. We study this reducibility and its interactions with the Turing reducibility, Π1 classes, hyperimmunity and other recursion theoretic notions. A natural variant of the Turing reducibility from the point of view of Martin-Löf randomness is the LR reducibility which was introduced in [12]. We say that A ≤...
متن کاملDegrees which do not bound minimal degrees
The high/low hierarchy respects the ordering of degrees, and so we can expect to find properties of order which are possessed by all degrees in a given hierarchy class. Such properties can also be found for classes of the generalized high/low hierarchy even though that hierarchy does not respect the ordering of the degrees. For example, Jockusch and Posner [4], extending a result of Cooper [l],...
متن کامل1-Generic Degrees Bounding Minimal Degrees Revisited
We show that over the base system P− + Σ2-bounding, the existence of a 1-generic degree < 0′′ bounding a minimal degree is equivalent to Σ2-induction.
متن کاملDegrees of Efficiency and Degrees of Minimality
In this work we characterize different types of solutions of a vector optimization problem by means of a scalarization procedure. Usually different scalarizing functions are used in order to obtain the various solutions of the vector problem. Here we consider different kinds of solutions of the same scalarized problem. Our results allow us to establish a parallelism between the solutions of the...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Journal of the American Pharmaceutical Association (1912)
سال: 1913
ISSN: 0898-140X
DOI: 10.1002/jps.3080020406