We propose a general theory whose main component are functorial assignments $$\mathbf{\Sigma} \mapsto \Omega_{\mathbf{\Sigma}} \in \mathbf{E}(\mathbf{\Sigma}),$$ for a large class of functors $\mathbf{E}$ from a certain category of bordered surfaces (${\mathbf \Sigma}$'s) to a suitable a target category of topological vector spaces. The construction is done by summing appropriate compositions of the initial data over all homotopy classes of successive excisions of embedded pair of pants. We provide sufficient conditions to guarantee these infinite sums converge and as a result, we can generate mapping class group invariant vectors $\Omega_{\mathbf \Sigma}$ which we call amplitudes. The initial data encode the amplitude for pair of pants and tori with one boundary, as well as the "recursion kernels" used for glueing. We give this construction the name of "geometric recursion", abbreviated GR. As an illustration, we show how to apply our formalism to various spaces of continuous function 查看全文>>