5
$\begingroup$

Does every Tits index belong to some semisimple algebraic group defined over the field of rational numbers?

Improve this question
$\endgroup$
1
  • 5
    $\begingroup$ No. For example, $E^{133}_{8,1}$ does not belong to an algebraic group over a number field. See the tables in the Boulder volume: J. Tits, Classification of algebraic semisimple groups, Proc. Symp Pure Math vol. 9, American Mathematical Society, Providence, RI, 1966, pp. 33–62. $\endgroup$
    – Mikhail Borovoi
    Commented Sep 7, 2023 at 11:01

0

Reset to default

You must log in to answer this question.

Browse other questions tagged .