Pseudo - Approximation for the Balanced Separator SDP
نویسندگان
چکیده
Lemma 2.2. It suffices to find disjoint L,R ∈ V such that they are (1) Large in Ω(n), or more formally stated, |L||R| ≥ α(n). (2) ∆-separated for ∆ = Ω( 1 logn) Let us define what ∆-separated means so that we can formalize this notion of “farness”. Recall that a distance from a vertex i to a set S is defined as d(i, S) = minj∈S d(i, j) (distance to the closest point in the set) and a distance from a set S to set T is defined as d(S, T ) = mini∈S,j∈T d(i, j) (distance between the two closest points from each of the sets).
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