Yoneda lemma

# Contents

## Idea

A classifying map or classifying morphism for a given object is a morphism into a classifying space that classified this object.

## Examples

• For subobjects one typically speaks of characteristic maps or characteristic functions. The corresponding classifiyng space is a subobject classifier . See there for more.

Created on June 26, 2011 16:46:44 by Urs Schreiber (89.204.153.100)