[[!redirects Sandbox > history]] [[!redirects Sandbox]] < [[nlab:Sandbox]] \section{Topological spaces} We define topological spaces using neighbourhood filters. Neighbourhood spaces * [https://math.stackexchange.com/questions/2769867/characterization-of-topology/2771383#2771383](https://math.stackexchange.com/questions/2769867/characterization-of-topology/2771383#2771383) * [https://math.stackexchange.com/questions/4077008/defining-a-topology-in-terms-of-filter-neighbourhoods](https://math.stackexchange.com/questions/4077008/defining-a-topology-in-terms-of-filter-neighbourhoods) category: redirected to nlab