• Corpus ID: 117819013

Null Surfaces: Counter-term for the Action Principle and the Characterization of the Gravitational Degrees of Freedom

@article{Parattu2015NullSC,
  title={Null Surfaces: Counter-term for the Action Principle and the Characterization of the Gravitational Degrees of Freedom},
  author={Krishnamohan Parattu and Sumanta Chakraborty and Bibhas Ranjan Majhi and Thanu Padmanabhan},
  journal={arXiv: General Relativity and Quantum Cosmology},
  year={2015}
}
Constructing a well-posed variational principle and characterizing the appropriate degrees of freedom that need to be fixed at the boundary are non-trivial issues in general relativity. For spacelike and timelike boundaries, one knows that (i) the addition of a counter-term [like the Gibbons-Hawking-York (GHY) counter-term] will make the variational principle well-defined and (ii) the degrees of freedom to be fixed on the boundary are contained in the induced 3-metric. These results, however… 

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