Composition algebras and the two faces of G2

We consider composition and division algebras over the real numbers: We note two roles for the group G2: as automorphism group of the octonions and as the isotropy group of a generic 3-form in 7 dimensions. We show why they are equivalent, by means of a regular metric. We express in some diagrams th...

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Detalles Bibliográficos
Autores: Boya, Luis J., Campoamor Stursberg, Otto-Rudwig
Tipo de recurso: artículo
Fecha de publicación:2010
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/43761
Acceso en línea:https://hdl.handle.net/20.500.14352/43761
Access Level:acceso abierto
Palabra clave:512
First exceptional Lie group G2
Composition algebra
Division algebra
Octonions
Automorphism group of octonions
Isotropy group
Quaternions
Split octonions
Tensors
Spin groups
F4
Álgebra
1201 Álgebra
Descripción
Sumario:We consider composition and division algebras over the real numbers: We note two roles for the group G2: as automorphism group of the octonions and as the isotropy group of a generic 3-form in 7 dimensions. We show why they are equivalent, by means of a regular metric. We express in some diagrams the relation between some pertinent groups, most of them related to the octonions. Some applications to physics are also discussed.