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Une fonction de Kolchin pour les corps imparfaits de degré d'imperfection fini

Published online by Cambridge University Press:  12 March 2014

Françoise Delon
Françoise Delon*
Affiliation:
C.N.R.S. et Université Paris 7, U.F.R. de Mathematiques, Case 7012. 2 Place Jussieu, 75251 Paris Cedex 5, France, E-mail: delon@logique.jussieu.fr
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Abstract

Non-perfect separably closed fields are stable, and not superstable. As a result, not all types can be ranked. We develop here a new tool, a “semi-rank”, which takes values in the non-negative reals, and gives a sufficient condition for forking of types. This semi-rank is built up from a transcendence function, analogous to the one considered by Kolehin in the context of differentially closed fields. It yields some orthogonality and stratification results.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 70 , Issue 2 , June 2005 , pp. 664 - 680
Copyright
Copyright © Association for Symbolic Logic 2005

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References

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