The good, the bad and the ugly .... of Horava gravity

Abstract

I review the good, the bad and the ugly of the non-projectable versions of Horava gravity. I explain how this non-relativistic theory was constructed and why it was touted with such excitement as a quantum theory of gravity. I then review some of the issues facing the theory, explaining how strong coupling occurs and why this is such a problem for both phenomenology and the question of renormalisability. Finally I comment on possible violations of Equivalence Principle, and explain why these could be an issue for Blas et al's "healthy extension". This paper was presented as a talk at PASCOS 2010 in Valencia.

7 pages

References in corpus (8)

• Quantum Gravity at a Lifshitz Point
• Test of the Equivalence Principle Using a Rotating Torsion Balance
• Models of non-relativistic quantum gravity: the good, the bad and the healthy
• Strong coupling in Horava gravity
• On the Extra Mode and Inconsistency of Horava Gravity
• Lorentz symmetry breaking as a quantum field theory regulator
• Predictive Power of Strong Coupling in Theories with Large Distance Modified Gravity
• Extended Hořava Gravity with Physical Ground-State Wavefunction

Cited by in corpus (14)

• Stability, ghost, and strong coupling in nonrelativistic general covariant theory of gravity with $\lambda \ne 1$
• Hamiltonian Analysis of Non-Relativistic Covariant RFDiff Horava-Lifshitz Gravity
• Horava gravity with mixed derivative terms
• Detailed balance condition and ultraviolet stability of scalar field in Horava-Lifshitz gravity
• Closure of the algebra of constraints for a nonprojectable Hořava model
• A unified thermodynamic picture of Hořava-Lifshitz black hole in arbitrary space time
• Black Holes in Hořava Gravity with Higher Derivative Magnetic Terms
• Anisotropic Extra Dimensions
• Higher derivative gravity with spontaneous symmetry breaking: Hamiltonian analysis of new covariant renormalizable gravity
• Weighted Power Counting and Perturbative Unitarity
• Aspects of Black Holes in Gravitational Theories with Broken Lorentz and Diffeomorphism Symmetries
• Brane structure from a scalar field in general covariant Horava-Lifshitz gravity
• Cosmological QCD phase transition in steady non-equilibrium dissipative Hořava-Lifshitz early universe
• Translation gauge field theory of gravity in Minkowski spacetime