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Updated: Jul 13, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
How continuous quantum measurements in finite dimensions are actually discrete
Giulio Chiribella1, Giacomo Mauro D'Ariano, Dirk Schlingemann
1QUIT Group, Dipartimento di Fisica A. Volta and INFM, via Bassi 6, 27100 Pavia, Italy. chiribella@fisicavolta.unipv.it
Physical Review Letters
|August 7, 2007
Summary
Quantum measurements with continuous outcomes can be simulated using a sequence of measurements with finite outcomes. This finding simplifies complex quantum experiments and enhances the understanding of quantum information processing.
Area of Science:
- Quantum Physics
- Information Theory
Background:
- Quantum measurements are fundamental to quantum mechanics.
- Continuous outcomes in quantum measurements pose theoretical and practical challenges.
Purpose of the Study:
- To demonstrate the realizability of continuous quantum measurements using finite measurement sets.
- To provide a theoretical framework for simplifying complex quantum measurement schemes.
Main Methods:
- Theoretical analysis of quantum measurement theory.
- Mathematical modeling of continuous random variables in quantum systems.
Main Results:
- Established that any quantum measurement with a continuous set of outcomes can be represented by a continuous random choice of measurements with a finite number of outcomes.
- Provided a method for constructing such finite measurement sets.
Conclusions:
- Continuous quantum measurements can be effectively approximated or realized through discrete measurement strategies.
- This work offers a pathway to simplify experimental designs and enhance the controllability of quantum systems.
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