2015/04/13 by Charis Anastopoulos, B. L. Hu, Bei-Lok Hu · 3 citations
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Classical mechanics #Gravitation #Gravitational field #Harmonic oscillator #Mechanical and Optical Resonators #Physics #Quantum #Quantum Mechanics and Applications #Quantum gravity #Quantum mechanics #Superposition principle #gr-qc #quant-ph
paper · pdf · doi:10.1088/0264-9381/32/16/165022
published as Class. Quantum Grav. 32, 165022 (2015) · 25 pages, 1 figure
arxiv created 2015/04/13 · openalex publication_date 2015/07/30 · arxiv updated 2015/08/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the nature of a gravitational two-state system (G2S) in the simplest setup in Newtonian gravity. In a quantum description of matter a single motionless massive particle can in principle be in a superposition state of two spatially separated locations. This superposition state in gravity, or gravitational cat state, would lead to fluctuations in the Newtonian force exerted on a nearby test particle. The central quantity of importance for this inquiry is the energy density correlation. This corresponds to the noise kernel in stochastic gravity theory , evaluated in the weak field nonrelativistic limit. In this limit quantum fluctuations of the stress–energy tensor manifest as the fluctuations of the Newtonian force. We describe the properties of such a G2S system and present two ways of measuring the cat state for the Newtonian force, one by way of a classical probe, the other a quantum harmonic oscillator. Our findings include: (i) mass density fluctuations persist even in single particle systems, and they are of the same order of magnitude as the mean ; (ii) a classical probe generically records a non-Markovian fluctuating force ; (iii) a quantum probe interacting with the G2S system may undergo Rabi oscillations in a strong coupling regime . This simple prototypical gravitational quantum system could provide a robust testing ground to compare predictions from alternative quantum theories , since the results reported here are based on standard quantum mechanics and classical gravity.