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arXiv · 1108.5220

Optimal Quantum Estimation for Gravitation

T. G. Downes·G. J. Milburn·C. M. Caves
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Abstract

Here we describe the quantum limit to measurement of the classical gravitational field. Specifically, we write down the optimal quantum Cramer-Rao lower bound, for any single parameter describing a metric for spacetime. The standard time-energy and Heisenberg uncertainty relations are shown to be special cases of the uncertainty relation for the spacetime metric. Four key examples are given, describing quantum limited estimation for: acceleration, black holes, gravitational waves and cosmology. We employ the locally covariant formulation of quantum field theory in curved spacetime, which allows for a manifestly spacetime independent derivation. The result is an uncertainty relation applicable to all causal spacetime manifolds.

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BibTeXRIS

T. G. Downes, G. J. Milburn, C. M. Caves. 2012-11-05. Optimal Quantum Estimation for Gravitation. https://arxiv.org/abs/1108.5220

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