Graph partitioning, balancing on within subset edge weights I'm interested in pointers to algorithms (approximation algorithms are fine) that attempt to partition a graph into two subsets such that the sum of the edge weights within each subset is (approximately) equal, and the sum of the edge weights between the two subsets is (approximately) minimal.

Any pointers are much appreciated.
The problem is called GRAPH CONDUCTANCE, and the best algorithm is by Arora et al.


  Sanjeev Arora, Satish Rao, Umesh V. Vazirani: Expander flows, geometric embeddings and graph partitioning. J. ACM 56(2): (2009)


This is a more accessible version, by the same authors:


  Sanjeev Arora, Satish Rao, Umesh V. Vazirani: Geometry, flows, and graph-partitioning algorithms. Commun. ACM 51(10): 96-105 (2008)