Conjugacy Classes of Maximal Tori in Simple Real Algebraic Groups and Applications

Doković, Dragomir Ž.

Canadian journal of mathematics, Tome 46 (1994) no. 4, pp. 699-717

Résumé

Let G be an almost simple complex algebraic group defined over R, and let G(R) be the group of real points of G. We enumerate the G(R)-conjugacy classes of maximal R-tori of G. Each of these conjugacy classes is also a single G(R) ̊-conjugacy class, where G(R) ̊ is the identity component of G(R), viewed as a real Lie group. As a consequence we also obtain a new and short proof of the Kostant-Sugiura's theorem on conjugacy classes of Cartan subalgebras in simple real Lie algebras.A connected real Lie group P is said to be weakly exponential (w.e.) if the image of its exponential map is dense in P. This concept was introduced in [HM] where also the question of identifying all w.e. almost simple real Lie groups was raised. By using a theorem of A. Borel and our classification of maximal R-tori we answer the above question when P is of the form G(R) ̊.

Détail

DOI : 10.4153/CJM-1994-039-5

Mots-clés : 20G20, 22E45, 22E46

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