Lie tori --- A simple characterization of extended affine Lie algebras
We show the existence of a nonzero graded form on
a Lie torus by the existence of a nonzero graded form on a structurable
torus.
This gives a simple characterization of the core of an extended affine
Lie algebra (EALA).
Namely, the core of any EALA is a Lie torus, and any centreless Lie
torus is the centreless core of some EALA.
We also show that a graded form on a Lie torus is unique up to scalars.
Y. Yoshii < yoshii@math.usask.ca >