Su alcune questioni di Calcolo delle Variazioni: omogeneizzazione in domini perforati con condizioni di Neumann e rilassamento
We consider the Dirichlet Laplacian in a thin curved three-dimensional rod. The rod is finite. Its cross-section is constant and small, and rotates along the reference curve in an arbitrary way. We find a two-parametric set of the eigenvalues of such operator and construct their complete asymptotic expansions. We show that this two-parametric set contains any prescribed number of the first eigenvalues of the considered operator. We obtain the complete asymptotic expansions for the eigenfunctions...
We consider the Dirichlet Laplacian in a thin curved three-dimensional rod. The rod is finite. Its cross-section is constant and small, and rotates along the reference curve in an arbitrary way. We find a two-parametric set of the eigenvalues of such operator and construct their complete asymptotic expansions. We show that this two-parametric set contains any prescribed number of the first eigenvalues of the considered operator. We obtain the complete asymptotic expansions for the eigenfunctions...
We consider a two-dimensional quantum waveguide composed of two semi-strips of width 1 and 1 − where > 0 is a small real parameter, the waveguide is gently converging. The width of the junction zone for the semi-strips is 1 + (√ε). We will present a sufficient condition for the existence of a weakly coupled bound state below , the lower bound of the continuous spectrum. This eigenvalue in the discrete spectrum is unique and its asymptotics is constructed and justified when...
Page 1