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Quantum clocks observe classical and quantum time dilation.

ABSTRACT: At the intersection of quantum theory and relativity lies the possibility of a clock experiencing a superposition of proper times. We consider quantum clocks constructed from the internal degrees of relativistic particles that move through curved spacetime. The probability that one clock reads a given proper time conditioned on another clock reading a different proper time is derived. From this conditional probability distribution, it is shown that when the center-of-mass of these clocks move in localized momentum wave packets they observe classical time dilation. We then illustrate a quantum correction to the time dilation observed by a clock moving in a superposition of localized momentum wave packets that has the potential to be observed in experiment. The Helstrom-Holevo lower bound is used to derive a proper time-energy/mass uncertainty relation.

SUBMITTER: Smith ARH

PROVIDER: S-EPMC7584645 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Quantum clocks observe classical and quantum time dilation.

Smith Alexander R H ARH Ahmadi Mehdi M

Nature communications 20201023 1

At the intersection of quantum theory and relativity lies the possibility of a clock experiencing a superposition of proper times. We consider quantum clocks constructed from the internal degrees of relativistic particles that move through curved spacetime. The probability that one clock reads a given proper time conditioned on another clock reading a different proper time is derived. From this conditional probability distribution, it is shown that when the center-of-mass of these clocks move in ...[more]

PMID: 33097702

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