Coordinate algebras of extended affine Lie algebras of type A1
The cores of extended affine Lie algebras of reduced types
were classified except for type A1.
In this paper we determine the coordinate algebra of
extended affine Lie algebras of type A1.
It turns out that such an algebra is a unital Zn-graded Jordan algebra
of a certain type, called a Jordan torus.
We classify Jordan tori and get five types of Jordan tori.
(To appear in J. Algebra)
Y. Yoshii <yyoshii@uottawa.ca>