IPM Calendar 
Wednesday 23 January 2019   Today  
Events for day: Wednesday 14 November 2018    
           14:00 - 15:00     Lecture
Tangles -vs- Trees


The topic of these talks is the structural theory of sparse graphs. More specifically, we study the interplay between highly cohesive substructures, which we figuratively refer to as `tangles', and decompositions over a (graph-theoretic) tree, which we simply call `trees'. At this point, we intentionally leave the meaning of these terms undefined and rely solely on the connotations they may carry.
We are primarily interested in situations in which a certain pair of a tangle and a tree cannot coexist: the existence of the specified substructure makes a decomposition of the desired kind impossible and vice versa. For example, tree-dec ...