%P 488-509 %T On the Curse of Dimensionality in the Ritz Method %O First online: 03 September 2015 %I Springer %V 168 %A Giorgio Gnecco %K Ritz method; Curse of dimensionality; Infinite-dimensional optimization; Approximation schemes; Extended Ritz method %L eprints3123 %D 2016 %X It is shown that the classical Ritz method of the calculus of variations suffers from the ?curse of dimensionality,? i.e., an exponential growth, as a function of the number of variables, of the dimension a linear subspace needs in order to achieve a desired relative improvement in the accuracy of approximation of the optimal solution value. The proof is constructive and is obtained by exhibiting a family of infinite-dimensional optimization problems for which this happens, namely those with quadratic functional and spherical constraint. The results provide a theoretical motivation for the search of alternative solution methods, such as the so-called ?extended Ritz method,? to deal with the curse of dimensionality. %J Journal of Optimization Theory and Applications %N 2 %R 10.1007/s10957-015-0804-y