New kinetic interactions for massive gravity?

作者：de Rham Claudia^*; Matas Andrew; Tolley Andrew J

来源：Classical and Quantum Gravity, 2014, 31(16): 165004.

DOI：10.1088/0264-9381/31/16/165004

• modified gravity
• massive gravity
• Hamiltonian analysis

We show that there can be no new Lorentz invariant kinetic interactions free from the Boulware-Deser ghost in four dimensions in the metric formulation of gravity, beyond the standard Einstein-Hilbert, up to total derivatives. We use dimensional deconstruction as a way to motivate a non-linear ansatz for potential new ghost-free kinetic interactions for massive gravity, bi-gravity and multi-gravity in four and higher dimensions. These interactions descend from Lovelock terms, and so naively one might expect the interactions to be ghost-free. However, we show that these new interactions inevitably lead to more than five propagating degrees of freedom. We then perform a general perturbative analysis in four dimensions, and show that the only term with two derivatives that does not introduce a ghost is the Einstein-Hilbert term. This result extends to all orders in perturbations.

• 出版日期2014-8-21