International Journal of Theoretical Physics

, Volume 47, Issue 9, pp 2382–2392 | Cite as

Conditional Probabilities and Collapse in Quantum Measurements

  • Roberto Laura
  • Leonardo Vanni


We show that including both the system and the apparatus in the quantum description of the measurement process, and using the concept of conditional probabilities, it is possible to deduce the statistical operator of the system after a measurement with a given result, which gives the probability distribution for all possible consecutive measurements on the system. This statistical operator, representing the state of the system after the first measurement, is in general not the same that would be obtained using the postulate of collapse.


Quantum measurements Projection postulate Conditional probabilities Consecutive measurements 


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Departamento de Física y Química, F.C.E.I.A.Universidad Nacional de RosarioRosarioArgentina
  2. 2.Instituto de Astronomía y Física del EspacioBuenos AiresArgentina

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