Group gradings on simple lie algebras of cartan and melikyan type

McGraw, Jason Melvin (2010) Group gradings on simple lie algebras of cartan and melikyan type. Doctoral (PhD) thesis, Memorial University of Newfoundland.

[img] [English] PDF - Accepted Version
Available under License - The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission.

Download (5MB)


In this thesis we explore the gradings by groups on the simple Cartan type Lie algebras and Melikyan algebras over algebraically closed fields of positive characteristic p > 2 (p = 5 for the Melikyan algebras). -- We approach the gradings by abelian groups without p-torsion on a simple Lie algebra L by looking at the dual group action. This action defines an abelian semisimple algebraic subgroup (quasi-torus) of the automorphism group of L. A result of Platonov says that any quasi-torus of an algebraic group is contained in the normalizer of a maximal torus. We show that if L is a simple graded Cartan or Melikyan type Lie algebra, then any quasi-torus of the automorphism group of L is contained in a maximal torus. Thus all gradings by groups without p-torsion are, up to isomorphism, coarsenings of the eigenspace decomposition of a maximal torus in the automorphism group. -- We also give examples of gradings by the cyclic group of order p which do not follow the pattern of the general description of gradings by groups without p-torsion as well as describe gradings by arbitrary groups on the restricted Witt algebra W(1; 1).

Item Type: Thesis (Doctoral (PhD))
Item ID: 8823
Additional Information: Includes bibliographical references (leaves 88-91).
Department(s): Science, Faculty of > Mathematics and Statistics
Date: 2010
Date Type: Submission
Library of Congress Subject Heading: Abelian groups; Automorphisms; Finite groups; Lie algebras

Actions (login required)

View Item View Item


Downloads per month over the past year

View more statistics