Stability of Singularity-free Cosmological Solutions in Hořava-Lifshitz Gravity
arXiv:1612.09077 · doi:10.1103/PhysRevD.95.044044
Abstract
We study stability of singularity-free cosmological solutions with positive cosmological constant based on projectable Hořava-Lifshitz (HL) theory. In HL theory, the isotropic and homogeneous cosmological solutions with bounce can be realized if spacial curvature is non-zero. By performing perturbation analysis around non-flat Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime, we derive a quadratic action and discuss the stability, i.e, ghost and tachyon-free conditions. Although the squared effective mass of scalar perturbation must be negative in infrared regime, we can avoid tachyon instability by considering strong Hubble friction. Additionally, we estimate the backreaction from the perturbations on background geometry, especially, against anisotropic perturbation in closed FLRW spacetime. It turns out that certain types of bouncing solution may be spoiled even if all perturbation modes are stable.
22 pages, 8 figures ; v3 : some results modified
References in corpus (15)
- Quantum Gravity at a Lifshitz Point
- Horava-Lifshitz Cosmology
- Strong coupling in Horava gravity
- Horava-Lifshitz Cosmology: A Review
- On the Extra Mode and Inconsistency of Horava Gravity
- Phenomenologically viable Lorentz-violating quantum gravity
- Black holes in Einstein-aether and Horava-Lifshitz gravity
- The Effective Field Theory of nonsingular cosmology
- A Trouble with Hořava-Lifshitz Gravity
- Thermodynamics and classification of cosmological models in the Horava-Lifshitz theory of gravity
- Dynamical Scalar Degree of Freedom in Horava-Lifshitz Gravity
- Oscillating Universe in Horava-Lifshitz Gravity
- Stability of spin-0 graviton and strong coupling in Horava-Lifshitz theory of gravity
- Breaking the scale invariance of the primordial power spectrum in Horava-Lifshitz Cosmology
- Non-Gaussianity from Lifshitz Scalar