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Locally extended affine Lie algebras

Jun Morita·Yoji Yoshii
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Abstract

We propose a new simplified definition of extended affine Lie algebras (EALAs for short), and also discuss a general version of extended affine Lie algebras, called locally extended affine Lie algebras (LEALAs for short). We prove a conjecture by V. Kac for LEALAs. It turns out that the root system of a LEALA becomes a locally finite version of extended affine root systems. Finally, several examples of new EALAs and LEALAs are introduced, and we classify LEALAs of nullity 0 with connection to locally finite split simple Lie algebras.

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Jun Morita, Yoji Yoshii. 2004-12-15. Locally extended affine Lie algebras. https://arxiv.org/abs/math/0412310

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