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We present a higher order generalisation of the clockwork mechanism starting from an underlying non-linear multigravity theory with a single scale and nearest neighbour ghost-free interactions. Without introducing any hierarchies in the underlying potential, this admits a family of Minkowski vacua around which massless graviton fluctuations couple to matter exponentially more weakly than the heavy modes. Although multi-diffeomorphisms are broken to the diagonal subgroup in our theory, an asymmetric distribution of conformal factors in the background vacua translates this diagonal symmetry into an asymmetric shift of the graviton gears. In particular we present a TeV scale multigravity model with ${cal O}(10)$ sites that contains a massless mode whose coupling to matter is Planckian, and a tower of massive modes starting at a TeV mass range and with TeV strength couplings. This suggests a possible application to the hierarchy problem as well as a candidate for dark matter.
We consider a class of higher order corrections with arbitrary power $n$ of the curvature tensor to the standard gravity action in arbitrary space-time dimension $D$. The corrections are in the form of Euler densities and are unique at each $n$ and $
Motivated by the vast string landscape, we consider the shear viscosity to entropy density ratio in conformal field theories dual to Einstein gravity with curvature square corrections. After field redefinitions these theories reduce to Gauss-Bonnet g
We demonstrate in two minisuperspace models that a perturbation expansion of quasiclassical Euclidean gravity has a factorial dependence on the order of the term at large orders. This behavior indicates that the expansion is an asymptotic series whic
We compute the one-loop divergences in a higher-derivative theory of gravity including Ricci tensor squared and Ricci scalar squared terms, in addition to the Hilbert and cosmological terms, on an (generally off-shell) Einstein background. We work wi
We give analytical arguments and demonstrate numerically the existence of black hole solutions of the $4D$ Effective Superstring Action in the presence of Gauss-Bonnet quadratic curvature terms. The solutions possess non-trivial dilaton hair. The hai