## arXiv Analytics

### arXiv:2006.16230 [gr-qc]AbstractReferencesReviewsResources

#### Constraint Algebra in Bigravity

Published 2020-06-29Version 1

The constraint algebra is derived in the 2nd order tetrad Hamiltonian formalism of the bigravity. This is done by a straightforward calculation without involving any insights, implicit functions, and Dirac brackets. The tetrad approach is the only way to present the bigravity action as a linear functional of lapses and shifts, and the Hassan-Rosen transform (characterized as complicated redefinition of the shift variable'' according to the authors) appears here not as an ansatz but as a fixing of a Lagrange multiplier. A comparison of this approach with the others is provided.

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