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arXiv · 2002.05754

Quantum probes for universal gravity corrections

Alessandro Candeloro·Cristian Degli Esposti Boschi·Matteo G. A. Paris
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Abstract

We address estimation of the minimum length arising from gravitational theories. In particular, we provide bounds on precision and assess the use of quantum probes to enhance the estimation performances. At first, we review the concept of minimum length and show how it induces a perturbative term appearing in the Hamiltonian of any quantum system, which is proportional to a parameter depending on the minimum length. We then systematically study the effects of this perturbation on different state preparations for several 1-dimensional systems, and we evaluate the Quantum Fisher Information in order to find the ultimate bounds to the precision of any estimation procedure. Eventually, we investigate the role of dimensionality by analysing the use of two-dimensional square well and harmonic oscillator systems to probe the minimal length. Our results show that quantum probes are convenient resources, providing potential enhancement in precision. Additionally, our results provide a set of guidelines to design possible future experiments to detect minimal length.

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Alessandro Candeloro, Cristian Degli Esposti Boschi, Matteo G. A. Paris. 2020-02-24. Quantum probes for universal gravity corrections. https://doi.org/10.1103/physrevd.102.056012

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