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An Evolutionary Formalism for Weak Quantum Measurements


Affiliations
1 Centre for High Energy Physics, Indian Institute of Science, Bengaluru 560 012, India
 

Unitary evolution and projective measurement are fundamental axioms of quantum mechanics. Even though projective measurement yields one of the eigenstates of the measured operator as the outcome, there is no theory that predicts which eigenstate will be observed in which experimental run. There exists only an ensemble description, which predicts probabilities of various outcomes over many experimental runs. We propose a dynamical evolution equation for the projective collapse of the quantum state in individual experimental runs, which is consistent with the well-established framework of quantum mechanics. In case of gradual weak measurements, its predictions for ensemble evolution are different from those of the Born rule. It is an open question whether or not suitably designed experiments can observe this alternate evolution.

Keywords

Born Rule, Decoherence, Density Matrix, Fixed Point, Quantum Trajectory, State Collapse.
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  • An Evolutionary Formalism for Weak Quantum Measurements

Abstract Views: 374  |  PDF Views: 123

Authors

Apoorva Patel
Centre for High Energy Physics, Indian Institute of Science, Bengaluru 560 012, India
Parveen Kumar
Centre for High Energy Physics, Indian Institute of Science, Bengaluru 560 012, India

Abstract


Unitary evolution and projective measurement are fundamental axioms of quantum mechanics. Even though projective measurement yields one of the eigenstates of the measured operator as the outcome, there is no theory that predicts which eigenstate will be observed in which experimental run. There exists only an ensemble description, which predicts probabilities of various outcomes over many experimental runs. We propose a dynamical evolution equation for the projective collapse of the quantum state in individual experimental runs, which is consistent with the well-established framework of quantum mechanics. In case of gradual weak measurements, its predictions for ensemble evolution are different from those of the Born rule. It is an open question whether or not suitably designed experiments can observe this alternate evolution.

Keywords


Born Rule, Decoherence, Density Matrix, Fixed Point, Quantum Trajectory, State Collapse.

References





DOI: https://doi.org/10.18520/cs%2Fv109%2Fi11%2F2017-2022