Shakhmurov, Veil2024-05-252024-05-2520121439-85161439-761710.1007/s10114-012-9547-y2-s2.0-84865404583https://doi.org/10.1007/s10114-012-9547-yhttps://hdl.handle.net/20.500.14517/821In this study, the estimates of approximation numbers of embedding operators in weighted spaces have been analyzed. These estimates depend on orders of differential operators, dimensions of function spaces and weighted functions. This fact implies that the associated embedding operators belong to Schatten class of compact operators. By using these estimates, the discreetness of spectrum and completion of root elements relating to principal nonselfedjoint degenerate differential operators is obtained.eninfo:eu-repo/semantics/closedAccessApproximation numbersKolmogorov numbersseparable boundary value problemsdifferential-operator equationsBanach-valued function spacesoperator-valued multipliersinterpolation of Banach spacesArticleQ428918831896WOS:0003074271000135