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Folding actions
Author(s) -
Lawther R.
Publication year - 1993
Publication title -
bulletin of the london mathematical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.396
H-Index - 48
eISSN - 1469-2120
pISSN - 0024-6093
DOI - 10.1112/blms/25.2.132
Subject(s) - mathematics , coset , conjugacy class , rank (graph theory) , action (physics) , character (mathematics) , combinatorics , multiplicity (mathematics) , permutation (music) , folding (dsp implementation) , group action , pure mathematics , group (periodic table) , geometry , physics , electrical engineering , engineering , quantum mechanics , acoustics
In this paper we begin by examining the action of E 6 ( q ) on the cosets of the subgroup F 4 ( q ): we give the rank and subdegrees, and show that it is multiplicity‐free, that is, the constituents of the permutation character are all distinct. It is found that the suborbits correspond to conjugacy classes of A 2 ( q ); we seek to explain this using the concept of ‘folding actions’. This enables the related action of 2 E 6 ( q 2 on F 4 ( q ) to be treated with little extra effort.