Table of contents

CONTENTS § 1. Introduction § 2. Problems with dissipation of parabolic type (semigroups of class 1) § 3. Semigroups of class 2. Equations of hyperbolic type References

CONTENTS Introduction § 1. Classes of functions. Boundary conditions § 2. Definition of the Maxwell operator. Inclusion in the elliptic theory § 3. Bounded domains with Lipschitz boundary § 4. Domains with piecewise-smooth boundary § 5. Asymptotic properties of the discrete spectrum of the operator § 6. Comments and bibliographic notes References

CONTENTS § 1. Introduction § 2. The effective Hamiltonian § 3. Turning points § 4. Comments and bibliographical indications References

CONTENTS Introduction § 1. Boundary values for abstract operators and the Krein formula for generalized resolvents § 2. Zero-radius potentials in diffraction problems § 3. Quantum-mechanical problems with energy-dependent potentials Conclusion References

CONTENTS Introduction § 1. Laplacians on a Riemann surface § 2. Variational formulae § 3. First variation of the function § 4. Second variation of the function § 5. Concluding remarks References

CONTENTS Introduction § 1. Boundedness and Hölder continuity of solutions of variational inequalities of general form § 2. Problems with obstacles in a domain § 3. Thin obstacles § 4. Diagonal systems § 5. Contact problems in elasticity theory § 6. Problems with convex constraints on the gradient of the solution References