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Going-Down Results for Ci-Fields

Published online by Cambridge University Press:  20 November 2018

Anthony J. Bevelacqua
Affiliation:
Department of Mathematics, University of North Dakota, Grand Forks, North Dakota 58202, USA email: [email protected]
Mark J. Motley
Affiliation:
Department of Mathematics, Pikeville College, Pikeville, Kentucky 41501, USA email: [email protected]
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Abstract

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We search for theorems that, given a ${{C}_{i}}$-field $K$ and a subfield $k$ of $K$, allow us to conclude that $k$ is a ${{C}_{j}}$ -field for some $j$. We give appropriate theorems in the case $\text{case }K=k\left( t \right)$ and $K=k\left( \left( t \right) \right)$. We then consider the more difficult case where $K/k$ is an algebraic extension. Here we are able to prove some results, and make conjectures. We also point out the connection between these questions and Lang's conjecture on nonreal function fields over a real closed field.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2006

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