It is known that the spaces of orders on orderable computable ÿelds can represent all 0 1 classes up to Turing degree. We show that the spaces of orders on orderable computable abelian and nilpotent groups cannot represent 0 1 classes in even a weak manner. Next, we consider presentations of ordered
Graph colorings and recursively bounded Π10-classes
✍ Scribed by J.B. Remmel
- Publisher
- Elsevier Science
- Year
- 1986
- Tongue
- English
- Weight
- 730 KB
- Volume
- 32
- Category
- Article
- ISSN
- 0168-0072
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