Graph expansion and the unique games conjecture

@inproceedings{Raghavendra2010GraphEA,
  title={Graph expansion and the unique games conjecture},
  author={Prasad Raghavendra and David Steurer},
  booktitle={STOC '10},
  year={2010}
}
The edge expansion of a subset of vertices S ⊆ V in a graph G measures the fraction of edges that leave S. In a d-regular graph, the edge expansion/conductance Φ(S) of a subset S ⊆ V is defined as Φ(S) = (|E(S, V\S)|)/(d|S|). Approximating the conductance of small linear sized sets (size δ n) is a natural optimization question that is a variant of the well-studied Sparsest Cut problem. However, there are no known algorithms to even distinguish between almost complete edge expansion (Φ(S) = 1… Expand
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