QFT in Curved Spacetime from Quantum Gravity: proper WKB decomposition of the gravitational component

• URL: http://arxiv.org/abs/2302.10832v2
• Date: Wed, 15 Mar 2023 09:07:14 GMT
• Title: QFT in Curved Spacetime from Quantum Gravity: proper WKB decomposition of the gravitational component
• Authors: Giulia Maniccia and Giovanni Montani and Stefano Antonini
• Abstract summary: We construct the proper low energy quantum field theory (QFT) limit of a full quantum gravity theory in the Born-Oppenheimer approach. The main accomplishment of the present work is to clarify that QFT in curved spacetime can be recovered in the low energy limit of quantum gravity only after averaging over the graviton degrees of freedom.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Starting from a re-analysis of previous work, we construct the proper low energy quantum field theory (QFT) limit of a full quantum gravity theory in the Born-Oppenheimer approach. We separate the gravitational sector into a classical background, given by a vacuum diagonal Bianchi I cosmology, and its quantum perturbations represented by the two graviton degrees of freedom; we further include quantum matter in the form of a test scalar field. We then implement a Born-Oppenheimer separation, where the gravitons and matter play the role of "slow" and "fast" quantum components respectively, and perform a Wentzel-Kramers-Brillouin (WKB) expansion in a Planckian parameter. The functional Schr\"odinger evolution for matter is recovered after averaging over quantum gravitational effects, provided that a condition is imposed on the gravitons' wave functional. Such a condition fixes the graviton dynamics and is equivalent to the purely gravitational Wheeler-DeWitt constraint imposed in previous approaches. The main accomplishment of the present work is to clarify that QFT in curved spacetime can be recovered in the low energy limit of quantum gravity only after averaging over the graviton degrees of freedom, in the spirit of effective field theory. Furthermore, it justifies a posteriori the implementation of the gravitational Wheeler-DeWitt equation on the "slow" gravitons' wave functional rather than assuming its validity a priori.

Related papers

• Quantum Sensing from Gravity as Universal Dephasing Channel for Qubits [41.96816488439435]
  WeExploit the generic phenomena of the gravitational redshift and Aharonov-Bohm phase. We show that entangled quantum states dephase with a universal rate. We propose qubit-based platforms as quantum sensors for precision gravitometers and mechanical strain gauges.
  arXiv  Detail & Related papers  (2024-06-05T13:36:06Z)
• Table-top nanodiamond interferometer enabling quantum gravity tests [34.82692226532414]
  We present a feasibility study for a table-top nanodiamond-based interferometer. By relying on quantum superpositions of steady massive objects our interferometer may allow exploiting just small-range electromagnetic fields.
  arXiv  Detail & Related papers  (2024-05-31T17:20:59Z)
• Bose-Einstein condensate as a quantum gravity probe; "Erste Abhandlung" [0.11704154007740832]
  We consider a Bose-Einstein condensate interacting with a gravitational wave for the case when the gravitational fluctuations are quantized. We observe that the solution of the time-dependent part of the pseudo-Goldstone boson has infusions from the noise induced by gravitons. We observe the effect of decoherence due to interacting phonon modes in the quantum gravitational Fisher information.
  arXiv  Detail & Related papers  (2024-04-09T06:57:00Z)
• Quantum effects in gravity beyond the Newton potential from a delocalised quantum source [1.1111141727030245]
  We show for the first time that gravity is not compatible with a classical description. Experiments such as the generation of gravitationally induced entanglement between two quantum sources of gravity can be explained with the Newton potential.
  arXiv  Detail & Related papers  (2024-02-15T19:33:04Z)
• Testing Quantum Gravity using Pulsed Optomechanical Systems [13.650870855008112]
  We consider the Schr"odinger-Newton (SN) theory and the Correlated Worldline (CWL) theory, and show that they can be distinguished from conventional quantum mechanics. We find that discriminating between the theories will be very difficult until experimental control over low frequency quantum optomechanical systems is pushed further.
  arXiv  Detail & Related papers  (2023-11-03T17:06:57Z)
• Decoherence of a composite particle induced by a weak quantized gravitational field [0.0]
  We study the decoherence of a quantum system induced by the quantized gravitational field and by its own quantum nature. Our results may be important in providing a better understanding of many phenomena like the decoherence induced by the gravitational time-dilation.
  arXiv  Detail & Related papers  (2023-08-14T20:49:16Z)
• Does the Universe have its own mass? [62.997667081978825]
  The mass of the universe is a distribution of non-zero values of gravitational constraints. A formulation of the Euclidean quantum theory of gravity is also proposed to determine the initial state. Being unrelated to ordinary matter, the distribution of its own mass affects the geometry of space.
  arXiv  Detail & Related papers  (2022-12-23T22:01:32Z)
• Is gravitational entanglement evidence for the quantization of spacetime? [0.0]
  Experiments witnessing the entanglement between two particles interacting only via the gravitational field have been proposed as a test whether gravity must be quantized. We present a parametrized model for the gravitational interaction of quantum matter on a classical spacetime, inspired by the de Broglie-Bohm formulation of quantum mechanics.
  arXiv  Detail & Related papers  (2022-05-02T14:37:24Z)
• Quantum dynamics corresponding to chaotic BKL scenario [62.997667081978825]
  Quantization smears the gravitational singularity avoiding its localization in the configuration space. Results suggest that the generic singularity of general relativity can be avoided at quantum level.
  arXiv  Detail & Related papers  (2022-04-24T13:32:45Z)
• Spacetime effects on wavepackets of coherent light [24.587462517914865]
  We introduce an operational way to distinguish between the overall shift in the pulse wavepacket and its genuine deformation after propagation. We then apply our technique to quantum states of photons that are coherent in the frequency degree of freedom. We find that the quantum coherence initially present can enhance the deformation induced by propagation in a curved background.
  arXiv  Detail & Related papers  (2021-06-23T14:20:19Z)
• Gravitational effects in macroscopic quantum systems: a first-principles analysis [0.0]
  We analyze the weak-field limit of General Relativity with matter and its possible quantisations. This analysis aims towards a predictive quantum theory to provide a first-principles description of gravitational effects in macroscopic quantum systems.
  arXiv  Detail & Related papers  (2021-03-14T21:29:11Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.