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arXiv · 1106.3027

Topological parameters in gravity

Romesh K. Kaul·Sandipan Sengupta
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Abstract

We present the Hamiltonian analysis of the theory of gravity based on a Lagrangian density containing Hilbert-Palatini term along with three topological densities, Nieh-Yan, Pontryagin and Euler. The addition of these topological terms modifies the symplectic structure non-trivially. The resulting canonical theory develops a dependence on three parameters which are coefficients of these terms. In the time gauge, we obtain a real SU (2) gauge theoretic description with a set of seven first class constraints corresponding to three SU (2) rotations, three spatial diffeomorphism and one to evolution in a timelike direction. Inverse of the coefficient of Nieh-Yan term, identified as Barbero-Immirzi parameter, acts as the coupling constant of the gauge theory.

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Romesh K. Kaul, Sandipan Sengupta. 2011-06-20. Topological parameters in gravity. https://doi.org/10.1103/physrevd.85.024026

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