--- date: 2022-03-26 20:37 modification date: Saturday 26th March 2022 20:37:52 title: "Ind objects" aliases: [Ind-objects, Ind-objects, Ind scheme, Ind schemes, Pro object, pro scheme] --- Last modified date: <%+ tp.file.last_modified_date() %> --- - Tags - #higher-algebra - Refs: - #todo/add-references - Links: - [kappa filtered](kappa%20filtered) --- # Ind objects $\Ind(\cat C)$ is the category of formal [filtered colimits](filtered%20colimits) ("inductive systems") of objects in $\cat C$. How to do this: take the [free cocompletion](free%20cocompletion.md) $\cat C \to [\cat C, \Set]$ and compute the colimit there. ![](attachments/Pasted%20image%2020210630222723.png) # Pro objects $\Pro\cat C$ is the category of formal limits ("projective systems") of objects in $\cat C$. Take the free completion $\cat C \to \opcat{ [\cat C, \Set] }$