English

On Noether's rationality problem for cyclic groups over $\mathbb{Q}$

Number Theory 2016-05-31 v1

Abstract

Let pp be a prime number. Let CpC_p, the cyclic group of order pp, permute transitively a set of indeterminates {x1,,xp}\{ x_1,\ldots ,x_p \}. We prove that the invariant field Q(x1,,xp)Cp\mathbb{Q}(x_1,\ldots ,x_p)^{C_p} is rational over Q\mathbb{Q} if and only if the (p1)(p-1)-th cyclotomic field Q(ζp1)\mathbb{Q}(\zeta_{p-1}) has class number one.

Keywords

Cite

@article{arxiv.1605.09228,
  title  = {On Noether's rationality problem for cyclic groups over $\mathbb{Q}$},
  author = {Bernat Plans},
  journal= {arXiv preprint arXiv:1605.09228},
  year   = {2016}
}

Comments

3 pages

R2 v1 2026-06-22T14:12:51.397Z