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Time-of-Arrival States

J. Oppenheim·B. Reznik·W. G. Unruh
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Abstract

Although one can show formally that a time-of-arrival operator cannot exist, one can modify the low momentum behaviour of the operator slightly so that it is self-adjoint. We show that such a modification results in the difficulty that the eigenstates are drastically altered. In an eigenstate of the modified time-of-arrival operator, the particle, at the predicted time-of-arrival, is found far away from the point of arrival with probability 1/2.

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J. Oppenheim, B. Reznik, W. G. Unruh. 1998-07-17. Time-of-Arrival States. https://doi.org/10.1103/physreva.59.1804

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