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The Time-Evolution of States in Quantum Mechanics according to the ETH-Approach
Jürg Fröhlich1, Alessandro Pizzo2
1Institut für theoretische Physik, ETH-Zürich, Zurich, Switzerland.
Abstract:
It is argued that the Schrödinger equation does not yield a correct description of the quantum-mechanical time evolution of states of isolated physical systems featuring events. A general statistical law replacing unitary Schrödinger evolution of states is then formulated within the so-called ETH-Approach to Quantum Mechanics. This law eliminates the infamous "measurement problem." Our general concepts and results are illustrated by an analysis of simple models describing a very heavy atom coupled to the quantized radiation field. In the limit where the speed of light tends to infinity these models can be treated quite explicitly.
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