American Journal of Physics

Collapse of wavefunctions and probability densities

Joseph Bishop Keller

Published Aug 1, 1990• 6 citations

Abstract

Three facts related to the collapse of quantum mechanical wavefunctions following measurements or observations are presented and explained. They are (1) in all stochastic theories, both classical and quantum mechanical, probability densities collapse following observations; (2) the laws of probability determine the probability density just after an observation in terms of that just before the observation and the result of the observation; (3) the wavefunction just after an observation can be found from that just before the observation by using the result of the observation, the laws of probability, and the assumption that immediate repetition of an observation yields the same result and does not change the wavefunction except for an arbitrary phase factor.

DOI: 10.1119/1.16355

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