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Foundations of Physics

, Volume 43, Issue 3, pp 310–328 | Cite as

Decoherent Histories of Spin Networks

  • David P. B. SchroerenEmail author
Article

Abstract

The decoherent histories formalism, developed by Griffiths, Gell-Mann, and Hartle (in Phys. Rev. A 76:022104, 2007; arXiv:1106.0767v3 [quant-ph], 2011; Consistent Quantum Theory, Cambridge University Press, 2003; arXiv:gr-qc/9304006v2, 1992) is a general framework in which to formulate a timeless, ‘generalised’ quantum theory and extract predictions from it. Recent advances in spin foam models allow for loop gravity to be cast in this framework. In this paper, I propose a decoherence functional for loop gravity and interpret existing results (Bianchi et al. in Phys. Rev. D 83:104015, 2011; Phys. Rev. D 82:084035, 2010) as showing that coarse grained histories follow quasiclassical trajectories in the appropriate limit.

Keywords

Decoherent histories Class operator Decoherence functional Spin network Quantum gravity Spin foams Path integral Coarse graining Probability 

Notes

Acknowledgements

I am indebted to my supervisor Carlo Rovelli, without whom this work would not have been possible. In addition, I would like to thank James Yearsley, Jonathan Halliwell, Edward Anderson, Petros Wallden, Kinjalk Lochan, Ed Wilson-Ewing, Simone Speziale, Aldo Riello, Wolfgang Wieland, as well as Leonard Cottrell for helpful comments and discussions. I am supported by the German National Academic Foundation (Studienstiftung des deutschen Volkes).

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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Balliol CollegeOxfordUK

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