Low Level Representations for E10 and E11

Hermann Nicolai; Thomas Fischbacher

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arXiv · hep-th/0301017

Low Level Representations for E10 and E11

Hermann Nicolai·Thomas Fischbacher

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Abstract

We work out the decomposition of the indefinite Kac Moody algebras ${E_{10}}$ and ${E_{11}}$ w.r.t. their respective subalgebras $A_9$ and $A_{10}$ at low levels. Tables of the irreducible representations with their outer multiplicities are presented for ${E_{10}}$ up to level $\ell = 18$ and for ${E_{11}}$ up to level $\ell =10$. On the way we confirm and extend existing results for ${E_{10}}$ root multiplicities, and for the first time compute non-trivial root multiplicities of ${E_{11}}$.

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Hermann Nicolai, Thomas Fischbacher. 2003-03-26. Low Level Representations for E10 and E11. https://arxiv.org/abs/hep-th/0301017

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