Energy norm based error estimators for adaptive BEM for hypersingular integral equations

For hypersingular integral equations in 2D and 3D, we analyze easy-to-implement error estimators like (h−h/2)(h−h/2)-based estimators, two-level estimators, and averaging on large patches and prove their equivalence. Moreover, we introduce some ZZ-type error estimators. All of these a posteriori error estimators are analyzed within the framework of localization techniques for the energy norm.