2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/69136The automorphism group of the vertex operator algebra $V_L^+$ is studied by using its action on isomorphism classes of irreducible $V_L^+$-modules. In particular, the shape of the automorphism group of $V_L^+$ is determined when $L$ is isomorphic to an even unimodular lattice without roots, $\sqrt2R$ for an irreducible root lattice $R$ of type $ADE$ and the Barnes-Wall lattice of rank 16.29 pagesQuantum AlgebraGroup TheoryThe Automorphism Group of the Vertex Operator Algebra $V_L^+$ for an even lattice $L$ without rootstext