The A.W. Mellon lectures in the fine arts 1956, National Gallery of Art, Washington.

"An attempt at a quantitative study of the formal aspects of the process of knowing, inferring, information, and learning" -- Preface.

This NATO Advanced Study Institute centered on large-scale molecular systems: Quantum mechanics, although providing a general framework for the description of matter, is not easily applicable to many concrete systems of interest; classical statistical methods, on the other hand, allow only a partial picture of the behaviour of large systems. The aim of the ASI was to present both aspects of the subject matter and to foster interaction between the scientists working in these important areas of theoretical physics and theoretical (...) chemistry. The quantum-mechanical part was mostly based on the operator-algebraic formulation of quantum mechanics and comprised quantum statistics of infinite systems with special em phasis on macroscopic observables, equilibrium conditions, irreversibility on the one hand, symmetry breaking for molecules in the radiation field and macroscopic quantum phenomena in the theory of superconductivity (BCS-theory) on the other hand. In addition, phase-space methods for many-body systems were also presented. Statistical physics was the main topic in the other lectures of the School; much emphasis was put on the statistical features of macros copic ("large") systems, the lectures dealt with mass and energy transport im polymers, in gels and in microemulsions, with aggregation and growth phenomena, with relaxation in complex, correlated systems, with conduction and optical properties of polymers, and with the means of describing disordered systems, above all fractals and related hierarchical models. (shrink)

We consider realism as a purely metaphysical regulative principle, not subject to scientific proof. In this sense, realism can be maintained in quantum mechanics, provided one does not claim that matter is made out of elementary particles. The epistemological dualism of subject versus object is achieved by a Cartesian cut between object and subject. Once the cut is made, we speak of an exophysical description, as opposed to the concept of an endosystem, a strictly closed physical system without any concept (...) of an observer. The cut resulting in the notion of the object always singles out the object's environment, with which the object interacts. Objects appear not in spite of but because they interact with their environment. In the intrinsically nonprobabilistic individual ontic interpretation, a quantum endosystem's intrinsic properties are represented by the commutative C*-subalgebras of a C*-algebra A. The exophysical description of the quantum system is generated by a context dependent fixing of a representation of A. The resulting von Neumann algebra refers to the contextual observables. The context dependence of the objects and the fact that they are entangled with their environment means that it is not realism that is refuted by quantum mechanics but atomism and the idea of context-independent objects. (shrink)