“…Recent approaches, like the wavelet multiscale methods [12] and the hyperbolic cross (sparse grids) approximation [8,88,95,101,28,29,30] allow to relax the curse of dimensionality, and already enable to handle the moderate dimensional problems, e.g., with d ≤ 10. The sparse Schur complement methods circumvent the curse of dimension by reduction to the interface or to the wire basket of the boundary [51,50].…”