User talk:MWinter4/4-flat graphs
Latest comment: 6 months ago by MWinter4 in topic Future work
Future work
edit- 4-flat graphs are closed under cloning edges and -transformations. It is conjectured that they are also closed under -transformations.[citation needed]
- Alternative to the notion of 4-flat graphs based on almost embeddings ( ) with its higher-dimensional analogues ( ) and leading to van der Holst's topological graph invariant .
- Alternative definitions of 4-flat using general CW-complex (instead of regular CW-complexes).[citation needed]