2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/77150The Virasoro operations in Witten's theory of two-dimensional topological gravity have a homotopy-theoretic interpretation as endomorphisms of an ordinary cohomology theory with coefficients in a localization of I. Schur's ring Δof Q-functions. The resulting theory has many of the features of a vertex operator algebra.16 pages; http://hopf.math.purdue.edu/Quantum AlgebraAlgebraic Geometry14H10 (primary), 55N35, 81R10 (secondary)text