## Tokyo Journal of Mathematics

### Toward Noether's Problem for the Fields of Cross-ratios

Hiroshi TSUNOGAI

#### Abstract

In this article, we consider an analogue of Noether's problem for the fields of cross-ratios, and discuss on a rationality problem which connects this with Noether's problem. We show that the affirmative answer of the analogue implies the affirmative answer for Noether's Problem for any permutation group with odd degree. We also obtain some negative results for various permutation groups with even degree.

#### Article information

Source
Tokyo J. Math., Volume 39, Number 3 (2017), 901-922.

Dates
First available in Project Euclid: 6 April 2017

https://projecteuclid.org/euclid.tjm/1491465735

Digital Object Identifier
doi:10.3836/tjm/1491465735

Mathematical Reviews number (MathSciNet)
MR3634298

Zentralblatt MATH identifier
06727291

#### Citation

TSUNOGAI, Hiroshi. Toward Noether's Problem for the Fields of Cross-ratios. Tokyo J. Math. 39 (2017), no. 3, 901--922. doi:10.3836/tjm/1491465735. https://projecteuclid.org/euclid.tjm/1491465735

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