Metric complements to subspaces in the Boolean cube

Abstract

We study the metric complements to subsets in the Boolean cube, i.e. the subsets maximally distant from a given subset. We obtain the general form for the metric complement of a linear subspace and some more exact description for the class of subspaces with basis of a special form. It is proved that the completely regular codes (including perfect and uniformly packed) are metrically regular.