Unramified Cohomology of Degree 3 and Noether's Problem Preliminary Version
نویسنده
چکیده
Let G be a finite group and W be a faithful representation of G over C. The group G acts on the field of rational functions C(W ). The aim of this paper is to give a description of the unramified cohomology group of degree 3 of the field of invariant functions C(W ) in terms of the cohomology of G when G is a group of odd order. This enables us to give an example of a group for which this field is not rational, although its unramified Brauer group is trivial. CONTENTS
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تاریخ انتشار 2008