Measurable signatures of quantum mechanics in a classical spacetime
Abstract
We propose an optomechanics experiment that can search for signatures of a fundamentally classical theory of gravity and in particular of the manybody SchrödingerNewton (SN) equation, which governs the evolution of a crystal under a selfgravitational field. The SN equation predicts that the dynamics of a macroscopic mechanical oscillator's centerofmass wave function differ from the predictions of standard quantum mechanics [H. Yang, H. Miao, D.S. Lee, B. Helou, and Y. Chen, Phys. Rev. Lett. 110, 170401 (2013), 10.1103/PhysRevLett.110.170401]. This difference is largest for lowfrequency oscillators, and for materials, such as tungsten or osmium, with small quantum fluctuations of the constituent atoms around their lattice equilibrium sites. Light probes the motion of these oscillators and is eventually measured in order to extract valuable information on the pendulum's dynamics. Due to the nonlinearity contained in the SN equation, we analyze the fluctuations of measurement results differently than standard quantum mechanics. We revisit how to model a thermal bath, and the wavefunction collapse postulate, resulting in two prescriptions for analyzing the quantum measurement of the light. We demonstrate that both predict features, in the outgoing light's phase fluctuations' spectrum, which are separate from classical thermal fluctuations and quantum shot noise, and which can be clearly resolved with state of the art technology.
 Publication:

Physical Review D
 Pub Date:
 August 2017
 DOI:
 10.1103/PhysRevD.96.044008
 arXiv:
 arXiv:1612.06310
 Bibcode:
 2017PhRvD..96d4008H
 Keywords:

 Quantum Physics
 EPrint:
 Phys. Rev. D 96, 044008 (2017)