A toy model for background independent string field theory

A bstract We study gauge theories of background fields associated to BRST quantized spinning particle models and identify background-independent algebraic structures which allow systematically reduce the spectrum subject some them dynamical equations motion. More specifically, we construct a manifestly extension model based on N = 2 particle. The resulting system describes an on-shell spin-1 field coupled off-shell including metric dilaton. Tensoring with given Lie algebra results in non-abelian model.