Abstract
The fourth Problem of Time facet is the Problem of Observables (or of Beables). The corresponding Background Independence aspect is Expression in Terms of Beables, to be approached by taking function spaces over a theory’s phase space. In constrained theories, observables must commute with the constraints. There are moreover various notions of constraints that can be used for this purpose, corresponding to distinct notions of observables. All sets of constraints thus used must however close, i.e. be constraint subalgebraic structures. Thus Expression in Terms of Beables logically postcedes the previous chapter’s Constraint Closure.
The corresponding beables subalgebraic structures also form a lattice, whose unit and zero elements are the unconstrained and Dirac observables. The rest of the lattice, on the other hand, is an ‘A-observables’ generalization of some theories possessing a notion of Kuchař observables ‘intermediate between’ unconstrained and Dirac observables. (These are all notions of data observables, as opposed to Chap. 27 and 28’s path and histories observables.) We additionally formulate notions of observables as solution spaces of particular partial (or functional) differential equations; we provide explicit examples of such equations for electromagnetism, general relativity and various model arenas. For various relational mechanics models, we note that their observables partial differential equations are solved by functions of the corresponding shapes and their momenta. Finally, we show how supergravity is among those theories for which Kuchař observables are supplanted by distinct notions of A-observables.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
Here is a smearing function. This is given in TRi form since first-class constraints are both trivially weak beables and TRi-smeared, pointing to all beables requiring TRi-smearing.
- 2.
The Author does not choose to base this book on partial observables due to these carrying ‘any change’ connotations. Elsewhere, the Partial Observables Approach has also be considered in combination with Internal Time Approaches. Here, internal time can provide the timestandard in schemes requiring a such if one is able or willing to pay the price for the usual inconveniences of a such; see e.g. [251, 252].
References
Anderson, E.: Problem of time in quantum gravity. Ann. Phys. 524, 757 (2012). arXiv:1206.2403
Anderson, E.: Beables/observables in classical and quantum gravity. SIGMA 10, 092 (2014). arXiv:1312.6073
Anderson, E.: The problem of time and quantum cosmology in the relational particle mechanics arena. arXiv:1111.1472
Anderson, E.: Explicit partial and functional differential equations for beables or observables. arXiv:1505.03551
Ashtekar, A., Tate, R.S., Uggla, C.: Minisuperspaces: observables and quantization. Int. J. Mod. Phys. D 2, 15 (1993). gr-qc/9302027
Barbour, J.B., Foster, B.Z.: Constraints and Gauge Transformations: Dirac’s Theorem is not Always Valid. arXiv:0808.1223
Bergmann, P.G.: “Gauge-invariant” variables in general relativity. Phys. Rev. 124, 274 (1961)
Bergmann, P.G., Komar, A.: The coordinate group symmetries of general relativity. Int. J. Theor. Phys. 5, 15 (1972)
Carlip, S.: Observables, gauge invariance, and time in \(2 + 1\) dimensional quantum gravity. Phys. Rev. D 42, 2647 (1990)
Carlip, S.: Measuring the metric in \((2 + 1)\)-dimensional quantum gravity. Class. Quantum Gravity 8, 5 (1991)
Coxeter, H.S.M.: Introduction to Geometry. Wiley, New York (1989)
DeWitt, B.S.: The quantization of geometry. In: Witten, L. (ed.) Gravitation: An Introduction to Current Research. Wiley, New York (1962)
Dirac, P.A.M.: Forms of relativistic dynamics. Rev. Mod. Phys. 21, 392 (1949)
Dirac, P.A.M.: Lectures on Quantum Mechanics. Yeshiva University, New York (1964)
Dittrich, B.: Partial and complete observables for canonical general relativity. Class. Quantum Gravity 23, 6155 (2006). gr-qc/0507106
Dittrich, B.: Partial and complete observables for Hamiltonian constrained systems. Gen. Relativ. Gravit. 38, 1891 (2007). gr-qc/0411013
Dittrich, B., Hoehn, P.A., Koslowski, T.A., Nelson, M.I.: Chaos, Dirac observables and constraint quantization. arXiv:1508.01947
Earman, J.: Gauge matters. Philos. Sci. 69, S209 (2002)
Gambini, R., Pullin, J.: Loops, Knots, Gauge Theories and Quantum Gravity. Cambridge University Press, Cambridge (1996)
Giddings, S.B., Marolf, D., Hartle, J.B.: Observables in effective gravity. Phys. Rev. D 74, 064018 (2006). hep-th/0512200
Henneaux, M., Teitelboim, C.: Quantization of Gauge Systems. Princeton University Press, Princeton (1992)
Isham, C.J.: Canonical quantum gravity and the problem of time. In: Ibort, L.A., Rodríguez, M.A. (eds.) Integrable Systems, Quantum Groups and Quantum Field Theories. Kluwer Academic, Dordrecht (1993). gr-qc/9210011
Kouletsis, I.: Covariance and time regained in canonical general relativity. Phys. Rev. D 78, 064014 (2008). arXiv:0803.0125
Kuchař, K.V.: Time and interpretations of quantum gravity. In: Kunstatter, G., Vincent, D., Williams, J. (eds.) Proceedings of the 4th Canadian Conference on General Relativity and Relativistic Astrophysics. World Scientific, Singapore (1992); Reprinted as Int. J. Mod. Phys. Proc. Suppl. D 20, 3 (2011)
Kuchař, K.V.: Canonical quantum gravity. In: Gleiser, R.J., Kozamah, C.N., Moreschi, O.M. (eds.) General Relativity and Gravitation 1992. IOP Publishing, Bristol (1993). gr-qc/9304012
Kuchař, K.V.: The problem of time in quantum geometrodynamics. In: Butterfield, J. (ed.) The Arguments of Time. Oxford University Press, Oxford (1999)
Laurent-Gengoux, C., Pichereau, A., Vanhaecke, P.: Poisson Structures. Springer, Berlin (2013)
Marolf, D.: Observables and a Hilbert space for Bianchi IX. Class. Quantum Gravity 12, 1441 (1995). arXiv:gr-qc/9409049
Marolf, D.: Solving the problem of time in minisuperspace: measurement of Dirac observables. Phys. Rev. D 79, 084016 (2009). arXiv:0902.1551
Muga, G., Sala Mayato, R., Egusquiza, I. (eds.): Time in Quantum Mechanics, vol. 1. Springer, Berlin (2008)
Muga, G., Sala Mayato, R., Egusquiza, I. (eds.): Time in Quantum Mechanics, vol. 2. Springer, Berlin (2010)
Page, D.N., Wootters, W.K.: Evolution without evolution: dynamics described by stationary observables. Phys. Rev. D 27, 2885 (1983)
Pons, J.M., Salisbury, D.C., Sundermeyer, K.A.: Revisiting observables in generally covariant theories in the light of gauge fixing methods. Phys. Rev. D 80, 084015 (2009). arXiv:0905.4564
Pons, J.M., Salisbury, D.C., Sundermeyer, K.A.: Observables in classical canonical gravity: folklore demystified In: Proceedings of 1st Mediterranean Conference on Classical and Quantum Gravity. arXiv:1001.2726
Rovelli, C.: Is there incompatibility between the ways time is treated in general relativity and in standard quantum mechanics? In: Ashtekar, A., Stachel, J. (eds.) Conceptual Problems of Quantum Gravity, p. 126. Birkhäuser, Boston (1991)
Rovelli, C.: Time in quantum gravity: an hypothesis. Phys. Rev. D 43, 442 (1991)
Rovelli, C.: Quantum evolving constants. Phys. Rev. D 44, 1339 (1991)
Rovelli, C.: GPS observables in general relativity. Phys. Rev. D 65, 044017 (2002). gr-qc/0110003
Rovelli, C.: Partial observables. Phys. Rev. 65, 124013 (2002). gr-qc/0110035
Rovelli, C.: Quantum Gravity. Cambridge University Press, Cambridge (2004)
Rovelli, C.: A note on the foundation of relativistic mechanics. I: relativistic observables and relativistic states. gr-qc/0111037
Rovelli, C.: A note on the foundation of relativistic mechanics. II: covariant Hamiltonian general relativity. gr-qc/0202079
Rovelli, C.: Forget time, fqXi ‘Nature of Time’ Essay Competition: Community First Prize. arXiv:0903.3832
Sorkin, R.D.: Forks in the road, on the way to quantum gravity. Int. J. Theor. Phys. 36, 2759 (1997). gr-qc/9706002
Thiemann, T.: Modern Canonical Quantum General Relativity. Cambridge University Press, Cambridge (2007)
Torre, C.G.: Observables for the polarized Gowdy model. Class. Quantum Gravity 23, 1543 (2006). gr-qc/0508008
Wüthrich, C.: Approaching the Planck scale from a generally relativistic point of view: a philosophical appraisal of loop quantum gravity. Ph.D. thesis, Pittsburgh (2006)
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 2017 Springer International Publishing AG
About this chapter
Cite this chapter
Anderson, E. (2017). Taking Function Spaces Thereover: Beables and Observables. In: The Problem of Time. Fundamental Theories of Physics, vol 190. Springer, Cham. https://doi.org/10.1007/978-3-319-58848-3_25
Download citation
DOI: https://doi.org/10.1007/978-3-319-58848-3_25
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-58846-9
Online ISBN: 978-3-319-58848-3
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)