Published online by Cambridge University Press: 20 November 2018
Let $p$ be an odd prime number, and let
$F$ be a field of characteristic not
$p$ and not containing the group
${{\mu }_{p}}$ of
$p$ -th roots of unity. We consider cyclic
$p$ -algebras over
$F$ by descent from
$L\,=\,F\left( {{\mu }_{p}} \right)$ . We generalize a theorem of Albert by showing that if
${{\mu }_{{{p}^{n}}}}\,\subseteq \,L$ , then a division algebra
$D$ of degree
${{p}^{n}}$ over
$F$ is a cyclic algebra if and only if there is
$d\,\in \,D$ with
${{d}^{{{P}^{n}}}}\,\in \,F\,-\,{{F}^{P}}$ . Let
$F(p)$ be the maximal
$p$ -extension of
$F$ . We show that
$F(p)$ has a noncyclic algebra of degree
$p$ if and only if a certain eigencomponent of the
$p$ -torsion of
$\text{Br(F(p)(}{{\mu }_{p}}\text{))}$ is nontrivial. To get a better understanding of
$F(p)$ , we consider the valuations on
$F(p)$ with residue characteristic not
$p$ , and determine what residue fields and value groups can occur. Our results support the conjecture that the
$p$ torsion in
$\text{Br}(F(p))$ is always trivial.