@article{Tarkhanov2011, author = {Tarkhanov, Nikolai Nikolaevich}, title = {The dirichlet to Neumann operator for elliptic complexes}, series = {Transactions of the American Mathematical Society}, volume = {363}, journal = {Transactions of the American Mathematical Society}, number = {12}, publisher = {American Mathematical Soc.}, address = {Providence}, issn = {0002-9947}, pages = {6421 -- 6437}, year = {2011}, abstract = {We define the Dirichlet to Neumann operator for an elliptic complex of first order differential operators on a compact Riemannian manifold with boundary. Under reasonable conditions the Betti numbers of the complex prove to be completely determined by the Dirichlet to Neumann operator on the boundary.}, language = {en} } @article{AlsaedyTarkhanov2014, author = {Alsaedy, Ammar and Tarkhanov, Nikolai Nikolaevich}, title = {Normally solvable nonlinear boundary value problems}, series = {Nonlinear analysis : theory, methods \& applications ; an international multidisciplinary journal}, volume = {95}, journal = {Nonlinear analysis : theory, methods \& applications ; an international multidisciplinary journal}, publisher = {Elsevier}, address = {Oxford}, issn = {0362-546X}, doi = {10.1016/j.na.2013.09.024}, pages = {468 -- 482}, year = {2014}, abstract = {We investigate nonlinear problems which appear as Euler-Lagrange equations for a variational problem. They include in particular variational boundary value problems for nonlinear elliptic equations studied by F. Browder in the 1960s. We establish a solvability criterion of such problems and elaborate an efficient orthogonal projection method for constructing approximate solutions.}, language = {en} }