Математическая логика, алгебра и теория чисел
Неприводимые ковры лиева типа $B_l$, $C_l$ и $F_4$ над полями
А. О. Лихачёваab,
Я. Н. Нужинa a Siberian Federal University, pr.Svobodny, 79, 660041, Krasnoyarsk, Russia
b North Caukasus Center for Mathematical Research, North Ossetian State University after K.L. Khetagurov
Аннотация:
V.M. Levchuk described irreducible carpets of Lie type of rank greater than
$1$ over the field
$F$, at least one additive subgroup of which is an
$R$-module, where
$F$ is an algebraic extension of the field
$R$, in assumption that the characteristic of the field
$F$ is different from
$0$ and
$2$ for the types
$B_l$,
$C_l$,
$F_4$, and for the type
$G_2$ it is different from
$0, 2$ and
$3$ (Algebra i Logika, 1983, 22, no. 5). It turned out that, up to conjugation by a diagonal element, all additive subgroups of such carpets coincide with one intermediate subfield between
$R$ and
$F$. We solve a similar problem for carpets of types
$B_l$,
$C_l$,
$F_4$ over a field of characteristic
$0$ and
$2$. It turned out that carpets appear in characteristic
$2$, which are parameterized by a pair of additive subgroups, and for types
$B_l$ and
$C_l$ one of these two additive subgroups may not be a field.
Ключевые слова:
Chevalley group, carpet of additive subgroups, carpet subgroup.
УДК:
512.54
MSC: 20G07 Поступила 28 марта 2022 г., опубликована
26 февраля 2023 г.
DOI:
10.33048/semi.2023.20.011