Z x Z-graded Lie algebras generated by the Virasoro algebra and $s{l}_2$

Yucai Su, Jiengfeng Zhang, Kaiming Zhao

The present paper is another step toward the classification of $\mathbb{Z}\times \mathbb{Z}$-graded Lie algebras: we classify $\mathbb{Z}\times \mathbb{Z}$-graded Lie algebras $A={\oplus }_{i,j\in \mathbb{Z}}{A}_{i,j}$ over a fi…