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arXiv · 1805.02179

Hamiltonian structure of bi-gravity, problem of ghost and bifurcation

Zahra Molaee·Ahmad Shirzad
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Abstract

We analyze the Hamiltonian structure of a general theory of bi-gravity where the interaction term is a scalar function of the form $ V(\mathcal{X}^{n}) $ where $ \mathcal{X} $ may be $\sqrt{g^{-1}f} $ or $ g^{-1}f $. We give necessary conditions for the interaction term of such a theory to be ghost free. We give a precise constraint analysis of the bi-gravity theory of Hassan- Rosen and show that the additional constraint which omit the ghost is just one possibility at the bifurcation point.

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Zahra Molaee, Ahmad Shirzad. 2018-05-06. Hamiltonian structure of bi-gravity, problem of ghost and bifurcation. https://doi.org/10.1088/1361-6382%2Fab496b

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