Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Unramified cohomology of degree 3 and Noether's problem   Let $G$ be a finite group and $W$ be a faithful representation of $G$ over
{\bf C}. The group $G$ acts on the field of rational functions $\mathbf C(W)$.
The aim of this paper is to give a description of the unramified cohomology
group of degree 3 of the field of invariant functions $\mathbf C(W)^G$ 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.

23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics