Spacetime foam: a review

Abstract

More than 65 years ago, John Wheeler suggested that quantum uncertainties of the metric would be of order one at the Planck scale, leading to large fluctuations in spacetime geometry and topology, which he termed "spacetime foam." In this review I discuss various attempts to implement this idea and to test it, both theoretically and, to a lesser extent, observationally.

arXiv comment42 pages (including 15 pages of referdences); v2: mainly more references, minor fixes; v3: corrected error on growth of triangulations, new discussion of higher order action, some other new references and clarifications

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Cited by in corpus (12)

• Promise of Future Searches for Cosmic Topology
• Searching for Decoherence from Quantum Gravity at the IceCube South Pole Neutrino Observatory
• Probing Lorentz invariance with a high-energy neutrino flare
• Causal structure and topology change in (2+1)-dimensional simplicial gravity
• Spacetime Foam Effects on Charged AdS Black Hole Thermodynamics
• No Flavor Anisotropy in the High-Energy Neutrino Sky Upholds Lorentz Invariance
• Quantum scalar field propagator in a stochastic gravitational plane wave
• Quantum Field Theory on Multifractal Spacetime: Varying Dimension and Ultraviolet Completeness
• The impact of a random metric upon a diffusing particle
• A Brief Thermodynamic Study For Four Dimensional Einstein Gauss Bonnet Black Holes Using Fractalised Barrow Entropy
• Signatures of Correlation of Spacetime Fluctuations in Laser Interferometers
• Foundational aspects of spinor structures and exotic spinors