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Strong coupling in Horava gravity
By studying perturbations about the vacuum, we show that Horava gravity suffers from two different strong coupling problems, extending all the way into the deep infra-red. The first of these is
General second order scalar-tensor theory, self tuning, and the Fab Four
Starting from the most general scalar-tensor theory with second order field equations in four dimensions, we establish the unique action that will allow for the existence of a consistent selftuning
Vacuum Energy Sequestering: The Framework and Its Cosmological Consequences
Recently we suggested a reformulation of General Relativity which completely sequesters from gravity all of the vacuum energy from a protected matter sector, assumed to contain the Standard Model.
Bi-galileon theory I: motivation and formulation
We introduce bi-galileon theory, the generalisation of the single galileon model introduced by Nicolis et al. The theory contains two coupled scalar fields and is described by a Lagrangian that is
Bi-galileon theory II: phenomenology
We continue to introduce bi-galileon theory, the generalisation of the single galileon model introduced by Nicolis et al. The theory contains two coupled scalar fields and is described by a
Sequestering the Standard Model Vacuum Energy
We propose a very simple reformulation of general relativity, which completely sequesters from gravity all of the vacuum energy from a matter sector, including all loop corrections and renders all
Self-tuning and the derivation of a class of scalar-tensor theories
We have recently proposed a special class of scalar tensor theories known as the Fab Four. These arose from attempts to analyse the cosmological constant problem within the context of Horndeski's
Manifestly Local Theory of Vacuum Energy Sequestering.
We present a manifestly local, diffeomorphism invariant, and locally Poincaré invariant formulation of vacuum energy sequestering. In this theory, quantum vacuum energy generated by matter loops is
Dark Energy after GW170817 Revisited.
TLDR
It is shown that the loophole ultimately fails when the effect of large scale inhomogeneities is included, and a class of theories, previously declared unviable in this context, whose anomalous gravitational wave speed is proportional to the scalar equation of motion is identified.
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