Short description: 
I am currently interested in several areas of graph theory and combinatorics. Recently, I have looked at a graph Ramsey theory type problem, two problems in discrete geometry, and many problems in extremal set theory. These problems all just happen to have an extremal theme to them, in the sense that we would like to maximise or minimise a certain quantity

Publications: 
 Liu, H., Morris, R., and Prince, N.: Highly connected monochromatic subgraphs of multicoloured graphs, J. Graph Theory (to appear).
 Liu, H., Morris, R., and Prince, N.: Highly connected multicoloured subgraphs of multicoloured graphs, Discrete Math. (to appear).
 Liu, H.: A new lower bound for the convex decomposition number of point sets in the plane, manuscript.
 Liu, H.: Finding k points in [N], (in preparation).
 Liu, H.: A different KruskalKatona theorem, (in preparation).
 Liu, H.: The convex decomposition number with a given number of extreme points, (in preparation). 