Transformation Groups

, 16:767 | Cite as

Root subsystems of loop extensions



We completely classify the real root subsystems of root systems of loop algebras of Kac–Moody Lie algebras. This classification involves new notions of “admissible subgroups” of the coweight lattice of a root system Ψ, and “scaling functions” on Ψ. Our results generalise and simplify earlier work on subsystems of real affine root systems.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Department of Mathematics, 255 Hurley BuildingUniversity of Notre DameNotre DameUSA
  2. 2.School of Mathematics and StatisticsUniversity of SydneySydneyAustralia

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