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arXiv · 1004.1810

Automorphism towers and automorphism groups of fields without Choice

Itay Kaplan·Saharon Shelah
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Abstract

This paper can be viewed as a continuation of [KS09] that dealt with the automorphism tower problem without Choice. Here we deal with the inequation which connects the automorphism tower and the normalizer tower without Choice and introduce a new proof to a theorem of Fried and Kollár that any group can be represented as an automorphism group of a field. The proof uses a simple construction: working more in graph theory, and less in algebra.

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Itay Kaplan, Saharon Shelah. 2011-11-17. Automorphism towers and automorphism groups of fields without Choice. https://arxiv.org/abs/1004.1810

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