A natural construction of Borcherds' Fake Baby Monster Lie Algebra
arXiv:math/0312106
Abstract
We use a Z_2-orbifold of the vertex operator algebra associated to the Niemeier lattice with root lattice A_3^8 and the no-ghost theorem of string theory to construct a generalized Kac-Moody algebra. Borcherds' theory of automorphic products allows us to determine the simple roots and identify the algebra with the fake baby monster Lie algebra.
13 pages, LaTeX