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تسجيل مستخدم جديدCosmological Perturbations in the Healthy Extension of Horava-Lifshitz gravity
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We study linear cosmological perturbations in the ``healthy extension of Horava-Lifshitz gravity which has recently been analyzed cite{BPS2}. We find that there are two degrees of freedom for scalar metric fluctuations, but that one of them decouples in the infrared limit. Also, for appropriate choices of the parameters defining the Lagrangian, the extra mode can be made well-behaved even in the ultraviolet.
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We consider the branch of the projectable Horava-Lifshitz model which exhibits ghost instabilities in the low energy limit. It turns out that, due to the Lorentz violating structure of the model and to the presence of a finite strong coupling scale,
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We investigate the linear cosmological perturbations in Hov{r}ava-Lifshitz gravity with a scalar field. Starting from the most general expressions of the metric perturbations as well as that of a canonical scalar field, we decompose the scalar, vecto
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