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arXiv:1810.11379 · International Journal of Modern Physics D

Parameter estimation for a Lorentz invariance violation

H. A. S. Costa, P. R. S. Carvalho, I. G. da Paz

Published Sep 9, 2018• 4 citations
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Abstract

We employ techniques from quantum estimation theory (QET) to estimate the Lorentz violation parameters in the (1+3)-dimensional flat spacetime. We obtain and discuss the expression of the quantum Fisher information (QFI) in terms of the Lorentz violation parameter [Formula: see text] and the momentum [Formula: see text] of the created particles. We show that the maximum QFI is achieved for a specific momentum [Formula: see text]. We also find that the optimal precision of estimation of the Lorentz violation parameter is obtained near the Planck scale.

DOI
10.1142/s0218271819500287

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We employ techniques from quantum estimation theory (QET) to estimate the Lorentz violation parameters in the (1+3)-dimensional flat spacetime. We obtain and discuss the expression of the quantum Fisher information (QFI) in terms of the Lorentz violation parameter [Formula: see text] and the momentum [Formula: see text] of the created particles. We show that the maximum QFI is achieved for a specific momentum [Formula: see text]. We also find that the optimal precision of estimation of the Lorentz violation parameter is obtained near the Planck scale.
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Abstract Quantum metrology studies the ultimate precision limit of physical quantities by using quantum strategy. In this paper we apply the quantum metrology technologies to the relativistic framework for estimating the deficit angle parameter of cosmic string spacetime. We use a two-level atom coupled to electromagnetic fields as the probe and derive its dynamical evolution by treating it as an open quantum system. We estimate the deficit angle parameter by calculating its quantum Fisher information(QFI). It is found that the quantum Fisher information depends on the deficit angle, evolution time, detector initial state, polarization direction, and its position. We then identify the optimal estimation strategies, i.e., maximize the quantum Fisher information via all the associated parameters, and therefore optimize the precision of estimation. Our results show that for different polarization cases the QFIs have different behaviors and different orders of magnitude, which may shed light on the exploration of cosmic string spacetime.
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