Quantum coherence and reality : in celebration of the 60th birthday of Yakir Aharonov : International Conference on Fundamental Aspects of Quantum Theory, University of South Carolina, Columbia, USA, 10-12 December 1992
Dynamic observation of flux lines based on the AB effect principle, A. Tonomura Aharonov effects for two slits and separated oscillatory fields interferences, N. Ramsey faster than Fourier, M. Berry quantum phase in action, A. Zee liberating exotic slaves, F. Wilczek evidence for a massive black hole in the center of our galaxy, C. Townes black holes, wormholes and the disappearance of global charge, S. Coleman unitarity of the black hole scattering matrix, G. t'Hooft topological phases and duality in electromagnetic and gravitational fields, J. Anandan non locality and objectivity in quantum state reduction, R. Penrose a non-polarization EPR experiment - observation of high-visibility Franson interference fringes, R.Y. Chiao et al toward It from Bit, J.A. Wheeler (para)bosons, (para)fermions, quons and other beasts in the menagerie of particle statistics, O.W. Greenberg et al a new formulation of quantum mechanics, Y. Aharonov. (Part contents).
Dynamic observation of flux lines based on the AB effect principle, A. Tonomura Aharonov effects for two slits and separated oscillatory fields interferences, N. Ramsey faster than Fourier, M. Berry quantum phase in action, A. Zee liberating exotic slaves, F. Wilczek evidence for a massive black hole in the center of our galaxy, C. Townes black holes, wormholes and the disappearance of global charge, S. Coleman unitarity of the black hole scattering matrix, G. t'Hooft topological phases and duality in electromagnetic and gravitational fields, J. Anandan non locality and objectivity in quantum state reduction, R. Penrose a non-polarization EPR experiment - observation of high-visibility Franson interference fringes, R.Y. Chiao et al toward It from Bit, J.A. Wheeler (para)bosons, (para)fermions, quons and other beasts in the menagerie of particle statistics, O.W. Greenberg et al a new formulation of quantum mechanics, Y. Aharonov. (Part contents).
The foundations of quantum mechanics has acquired tremendous importance in recent years for three reasons: First, a large number of experiments have tested concepts which previously were purely theoretical. Second, ideas from the foundations of quantum mechanics are being applied now to many fields such as condensed matter physics, quantum statistics, quantum cosmology and quantum gravity. Third, difficulties in constructing a quantum cosmology and theory of gravity have made many theorists examine the foundations of quantum theory to see if quantum mechanics itself needs to be modified. Very distinguished physicists from around the world gave talks on their recent research on a variety of theoretical and experimental aspects on these subjects at this conference.
Some reflections on the EPR work, N. Rosen Philosophical reflections on EPR, A. Shimony Can EPR non-locality be geometrical? Y. Ne'Eman EPR in the 1990's: from paradox to crucial ingredient in frontier experiments, H.J. Lipkin Eistein-Podolsky-Rosen interferometry, A. Zeilinger Quantum phase, photon counting and EPR variables, M.T. Fontenelle, M. Freyberger, M. Heni, W.P. Schleich, M.S. Zubairy Fine structure of EPR state and universal quantum correlation, B.S. Tsirelson Locality, reality, EPR, and Bell's inequality, M. Lokajicek On the Pauli wave function and the EPR paradox, F. Piazzese Quantum nonreproducibility at the individual level as a resolution of quantum paradoxes, W. de Baere Quantum nonlocality and Bell's inequality, W.M. de Muynpk, W. De Baere On the conjecture that Bell's theorem is not true, E. Santos temporal Bell inequalities in quantum networks Quantum-optical Bell correlations in phase space, U. Leonhardt, J.A. Vaccaro More powerful tests of nonlocality by sequences of measurements, S. Popescu Nonlocality as an axiom for quantum theory, D. Rohrlich, S. Popescu Uncertainty principle for nonhermitian operators and its applications, L.P. Piyaevskii Measures of entanglement, A. Shimony Generalized two-mode squeezing and quantum entanglement Wave-particle duality for a single photon, A. Aspect Causality and nonlocality in faster- than- light photon travel Geometry of quantum inference, S.L. Braunstein Quantum information: how much information in a state vector? C.M. Caves, C.A. Fuchs Quantum and classical information transmission acts and reducibilities, C.H. Bennett Consequences and inconsequences of cryptic constrains, L.S. Schulman The meaning of protective measurements, Y. Aharonov, J. Anandan, L. Vaidman From E.P.R. to G.H.Z.: conference highlights, A. Peres.
Quantum physics demands some radical revision of our fundamental beliefs about physical reality. We know that because there are certain verified physical phenomena-two-slit interference, the disappearance of interference upon monitoring, violations of Bell's inequality-that have no classical analogs. But the exact nature of that revision has been under dispute since the foundation of quantum theory. I offer a method of clarifying what the commitments of a clearly formulated physical theory are, and apply it to a discussion of some options available to account for another non-classical phenomenon: the Aharonov-Bohm effect.
Numerical gauge theories with topological fidelity, A.P. Balachandran Lee-Yang Zeros and phase structure of non-compact lattice QED, I. Barbour Intrinsic irreversibility of quantum systems, A. Bohn Nonrelativistic quantum dynamics on manifolds, H-D. Doebner Underground particle astrophysics, G. Giacomelli Decoherence and time scales, Y.S. Kim Search for neutral Higgs Bosons, M. Krawczyk Integrals of motion and quantum tomography, V. Man'ko Coherent states map for MIC-Kepler system, A. Odzijewicz Two-photon decay of the MSSM Higgs particle, P. Osland Shielding and the Aharonov-Bohm effect, M. Peshkin Interacting Wess-Zumino-Witten systems, L.O'Raifeartaigh Particle physics in international collaboration - the future, D. Saxon Long-range spin-dependent forces, J. Sucher.
This special issue celebrates the discovery of two of the most important aspects of quantum mechanics: the Aharonov–Bohm effect and the Berry phase. The issue includes work presented at two conferences, 50 Years of the Aharonov–Bohm Effect, 11–14 October 2009, Tel Aviv University, Israel, and the Aharonov–Bohm Effect and Berry Phase 50/25 Anniversary, 14–15 December 2009, Bristol University, UK. The Aharonov–Bohm (AB) effect and the Berry phase have many things in common, apart from the happy coincidence that they were discovered 25 years apart, making possible such a joint anniversary. First, they were both discovered in the same place, the H H Wills Physics Laboratory, University of Bristol, UK. Second, they both were there for everybody to see from day one, from the very beginning of quantum mechanics. They were, so to say, right on the surface; there was no need for sophisticated mathematics or involved constructions. Yet it took so long for somebody to see them. The explanation, we dare to speculate, is that they are so unusual, they challenge so much our everyday experience and ingrained intuitions about physics that it was difficult to recognise them. Third, both the AB effect and the Berry phase are quintessentially quantum; they both manifest themselves as topological/geometric quantum phases. The AB effect revolutionized our understanding of the role of potentials in physics. For the first time, it was shown that a particle moving in a field-free region could be affected by a field in a disjoint region. In doing so, it shattered one of the strongest held principles of physics. In the case of the Berry phase, the importance lies in its absolute generality—the topological/geometric phase named after Berry is acquired by all physical systems when the external parameters they depend upon undergo an adiabatic cyclic change. Remarkably this phase depends only on the geometry of the cyclic path in the abstract parameter space, a fact which deepens our appreciation of the underlying geometry of quantum mechanics. The AB effect and the Berry phase are ubiquitous in modern physics and have implications ranging from the most fundamental to the very applied. First and foremost, they give a deeper understanding of the nature of quantum mechanics itself. Furthermore, we find them in fields as varied as cosmology, particle physics, non-abelian gauge theories, condensed matter, chemical and molecular physics, and laser dynamics. Generalizations of the AB effect to non-abelian gauge theories, such as the Wilson and `t Hooft loops, are important tools for studying confinement and spontaneous symmetry breaking. They explain charge quantization, the quantum Hall effect and the Josephson junction and also play a crucial role in electron microscope holography. Without them an understanding of many effects in the new field of mesoscopic physics, where tiny electronic circuits exhibit quantum behaviour, would be impossible. Like good wine, the AB effect and the Berry phase become finer and more appreciated with time. Even though they appear in textbooks and encyclopaedias, the number of researchers thinking and publishing papers on these two effects is increasing annually. The AB effect and the Berry phase keep being observed in new systems and with every day that passes novel applications are routinely found. This special issue is just a small snapshot of the state of the art 50 and 25 years, respectively, from their discoveries.