Mathematical Results in Quantum Mechanics: International Conference in Blossin (Germany), May 17–21, 1993(70 Operator Theory: Advances and Applications)

The last decades have demonstrated that quantum mechanics is an inexhaustible source of inspiration for contemporary mathematical physics. Of course, it seems to be hardly surprising if one casts a glance toward the history of the subject; recall the pioneering works of von Neumann, Weyl, Kato and their followers which pushed forward some of the classical mathematical disciplines: functional analysis, differential equations, group theory, etc. On the other hand, the evident powerful feedback changed the face of the "naive" quantum physics. It created a contem­ porary quantum mechanics, the mathematical problems of which now constitute the backbone of mathematical physics. The mathematical and physical aspects of these problems cannot be separated, even if one may not share the opinion of Hilbert who rigorously denied differences between pure and applied mathemat­ ics, and the fruitful oscilllation between the two creates a powerful stimulus for development of mathematical physics. The International Conference on Mathematical Results in Quantum Mechan­ ics, held in Blossin (near Berlin), May 17-21, 1993, was the fifth in the series of meetings started in Dubna (in the former USSR) in 1987, which were dedicated to mathematical problems of quantum mechanics. A primary motivation of any meeting is certainly to facilitate an exchange of ideas, but there also other goals. The first meeting and those that followed (Dubna, 1988; Dubna, 1989; Liblice (in the Czech Republic), 1990) were aimed, in particular, at paving ways to East-West contacts.

Table of Contents:
1 Schrödinger and Dirac operators.- Discrete spectrum of the periodic Schrödinger operator for non-negative perturbations.- The discrete spectrum in a gap of the continuous one for compact supported perturbations.- Schrödinger operators with strong local magnetic perturbations: Existence of eigenvalues in gaps of the essential spectrum.- Regularity of the nodal sets of solutions to Schrödinger equations.- Results in the spectral theory of Schrödinger operators with wide potential barriers.- Stark ladders and perturbation theory.- Singular potentials: algebraization.- Asymptotic behavior of the resolvent of the Dirac operator.- Discrete spectrum of the perturbed Dirac operator.- 2 Generalized Schrödinger operators.- The spectrum of Schrödinger operators in Lp(Rd) and in C0(Rd).- On spectral properties of generalized Schrödinger operators.- A Fermi-type rule for contact embedded-eigenvalue perturbations.- A simple model for predissociation.- Scattering on several solenoids.- Hall conductance of Riemann surfaces.- 3 Stochastic spectral analysis.- Framework and results of stochastic spectral analysis.- Occupation time asymptotics to the decay of eigenfunctions.- Holomorphic semigroups and Schrödinger equations.- Some problems on submarkovian semigroups.- Smoothness estimates and uniqueness for the Dirichlet operator.- Trace ideal properties of perturbed Dirichlet semigroups.- Quantum dynamical semigroups.- 4 Many-body problems and statistical physics K.B. Sinha.- Limits of infinite order, dimensionality or number of components for random finite-difference operators.- Atoms at finite density and temperature and the spectra of reduced density matrices.- Quantum fluctuations in the many-body problem.- General Hamiltonians and model Hamiltonians.- Poisson fieldsrepresentations in the statistical mechanics of conitinuous systems.- Exact ground states for quantum spin chains.- The spectrum of the spin-boson model.- A survey of Wigner-Poisson problems.- 5 Chaos.- Classical d’Alembert field in an one-dimensional pulsating region.- Irregular scattering in one-dimensional periodically driven systems.- Relatively random unitary operators.- 6 Operator theory and its application.- A trace formula for obstacles problems and applications.- Propagation in irregular optic fibres.- Singular perturbations, regularization and extension theory.- Adiabatic reduction theory. Semiclassical S-matrix for N-state one-dimensional systems.- The functional structure of the monodromy matrix for Harper’s equation.- Eigenfunction expansion of right definite multiparameter problems.- Singularly perturbed operators.- Some problems of p-adic quantum theory.