Geometry and observables in (2+1)-gravity
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We review the geometrical properties of vacuum spacetimes in (2+1)-gravity with vanishing cosmological constant. We explain how these spacetimes are characterised as quotients of their universal cover by holonomies. We explain how this description can be used to clarify the geometrical interpretation of the fundamental physical variables of the theory, holonomies and Wilson loops. In particular, we discuss the role of Wilson loop observables as the generators of the two fundamental transformations that change the geometry of (2+1)-spacetimes, grafting and earthquake. We explain how these variables can be determined from realistic measurements by an observer in the spacetime.
KeywordsGeneral relativity Quantum gravity Three-dimensional gravity Teichmüller geometry Wilson loops
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- 2.Benedetti, R., Bonsante, F.: Canonical Wick rotations in 3-dimensional gravity. AMS Memoirs 926, 198 (2009)Google Scholar
- 12.Thurston W.P.: Earthquakes in two-dimensional hyperbolic geometry. In: Epstein, D.B. (eds) Low Dimensional Topology and Kleinian Groups., pp. 91–112. Cambridge University Press, Cambridge (1987)Google Scholar
- 14.Meusburger, C.: Global Lorentzian geometry from lightlike geodesics: What does an observer in (2+1)-gravity see? arXiv:1001.1842 [math-ph] (2009)Google Scholar