English

Noncommutative Noether's problem is almost equivalent to the classical Noether's problem

Quantum Algebra 2021-12-13 v2 Representation Theory

Abstract

Motivated by the classical Noether's problem, J. Alev and F. Dumas proposed the following question, commonly referred to as the noncommutative Noether's problem: Let a finite group GG act linearly on Cn,\mathbb{C}^n, inducing the action on Frac(An(C))\text{Frac}(A_n(\mathbb{C}))-the skew field of fractions of the nn-th Weyl algebra An(C),A_n(\mathbb{C}), then is Frac(An(C))G\text{Frac}(A_n(\mathbb{C}))^G isomorphic to Frac(An(C))?\text{Frac}(A_n(\mathbb{C}))? In this note we show that if Frac(An(C))GFrac(An(C)),\text{Frac}(A_n(\mathbb{C}))^{G}\cong \text{Frac}(A_n(\mathbb{C})), then for any algebraically closed field kk of large enough characteristic, field k(x1,,xn)Gk(x_1,\cdots, x_n)^G is stably rational. This result allows us to produce counterexamples to the noncommutative Noether's problem based on well-known counterexamples to the Noether's problem for algebraically closed fields.

Keywords

Cite

@article{arxiv.2104.08674,
  title  = {Noncommutative Noether's problem is almost equivalent to the classical Noether's problem},
  author = {Akaki Tikaradze},
  journal= {arXiv preprint arXiv:2104.08674},
  year   = {2021}
}

Comments

4 pages, to appear in Advances in Math

R2 v1 2026-06-24T01:17:05.765Z