ua nt - p h / 98 06 06 0 v 2 2 3 Ju n 19 98 Operator Formulation of Classical Mechanics and the Problem of Measurement

ua nt - p h / 98 06 03 6 v 1 1 1 Ju n 19 98 Causality , particle localization and positivity of the energy

Positivity of the Hamiltonian alone is used to show that particles, if initially localized in a finite region, immediately develop infinite tails.

ua nt - p h / 98 05 06 4 v 2 5 Ju n 19 98 When does a Measurement or Event Occur ?

Within quantum mechanics it is possible to assign a probability to the chance that a measurement has been made at a specific time t. However, the interpretation of such a probability is far from clear. We argue that a recent measuring scheme of Rovelli's (quant-ph/9802020) yields probabilities which do not correspond to the conventional probabilities usually assigned in quantum mechanics. The s...

ua nt - p h / 98 07 06 3 v 1 2 2 Ju l 1 99 8 Twin - photon techniques for fiber measurements

ua nt - p h / 99 06 09 2 v 2 1 3 Ju l 2 00 0 Continuous Quantum Measurement and the Emergence of Classical Chaos LA - UR - 99 - 3187

We formulate the conditions under which the dynamics of a continuously measured quantum system becomes indistinguishable from that of the corresponding classical system. In particular, we demonstrate that even in a classically chaotic system the quantum state vector conditioned by the measurement remains localized and, under these conditions, follows a trajectory characterized by the classical ...

ar X iv : h ep - t h / 98 06 19 2 v 1 2 3 Ju n 19 98 On time - dependent quasi - exactly solvable problems

In this paper we demonstrate that there exists a close relationship between quasi-exactly solvable quantum models and two special classes of classical dynamical systems. One of these systems can be considered a natural generalization of the multi-particle Calogero-Moser model and the second one is a classical matrix model. This work was partially supported by DFG grant No. 436 POL 113/77/0 (S) ...