# On a Rationality Problem for Fields of Cross-ratios

```@article{Reichstein2020OnAR,
title={On a Rationality Problem for Fields of Cross-ratios},
author={Zinovy Reichstein},
journal={Tokyo Journal of Mathematics},
year={2020}
}```
• Z. Reichstein
• Published 29 June 2018
• Mathematics
• Tokyo Journal of Mathematics
Let k be a field, x1, . . . , xn be independent variables and Ln = k(x1, . . . , xn). The symmetric group Σn acts on Ln by permuting the variables, and the projective linear group PGL2 acts by
1 Citations
On a rationality problem for fields of cross-ratios II
• Mathematics
• 2020
Abstract Let k be a field, \$x_1, \dots , x_n\$ be independent variables and let \$L_n = k(x_1, \dots , x_n)\$ . The symmetric group \$\operatorname {\Sigma }_n\$ acts on \$L_n\$ by permuting theExpand

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