Gauge fixing in (2+1)-gravity: Dirac bracket and spacetime geometry
نویسندگان
چکیده
منابع مشابه
Gauge fixing in (2+1)-gravity: Dirac bracket and spacetime geometry
We consider (2+1)-gravity with vanishing cosmological constant as a constrained dynamical system. By applying Dirac’s gauge fixing procedure, we implement the constraints and determine the Dirac bracket on the gauge-invariant phase space. The chosen gauge fixing conditions have a natural physical interpretation and specify an observer in the spacetime. We derive explicit expressions for the res...
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We apply Dirac’s gauge fixing procedure to (2+1)-gravity with vanishing cosmological constant. For general gauge fixing conditions based on two point particles, this yields explicit expressions for the Dirac bracket. We explain how gauge fixing is related to the introduction of an observer into the theory and show that the Dirac bracket is determined by a classical dynamical r-matrix. Its two d...
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background and aims: to obtain maximum advantages from orthodontic fixed appliances and to achieve the desired final occlusion, correct bracket positioning is highly necessary. in order to measure and determine bracket’s height, diverse gauges have been used. the objective of the present study is to determine and compare bracket positioning accuracy by using height bracket positioning gauge (hb...
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ژورنال
عنوان ژورنال: Classical and Quantum Gravity
سال: 2011
ISSN: 0264-9381,1361-6382
DOI: 10.1088/0264-9381/28/12/125008