Work

When is multimetric gravity ghost-free?

Year: 2012

Type: article

Abstract: We study ghosts in multimetric gravity by combining the minisuperspace and the Hamiltonian constraint analysis. We first revisit bimetric gravity and explain why it is ghost-free. Then, we apply our method to trimetric gravity and clarify when the model contains a ghost. More precisely, we prove trimetric gravity generically contains a ghost. However, if we cut the interaction of a pair of metrics, trimetric gravity becomes ghost-free. We further extend the Hamiltonian analysis to general multimetric gravity and calculate the number of ghosts in various models. Thus, we find multimetric gravity with loop type interactions never becomes ghost-free.

Source: Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields

DOI: 10.1103/physrevd.86.084052

Authors: Kouichi Nomura, Jiro Soda

Institution: Kyoto University

Language: English

Topic: Cosmology and Gravitation Theories

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funder: Japan Society for the Promotion of Science

Awards: research on cosmological nonlinear and non-perturbative gravitational phenomena, The exploration of extradimensions in terms of a variety of cosmophysical phenomena caused by axionic moduli, G5473262123, Anisotropic inflation from supergravity