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We consider a higher derivative gravity theory in four dimensions with a negative cosmological constant and show that vacuum solutions of both Lifshitz type and Schr{o}dinger type with arbitrary dynamical exponent z exist in this system. Then we find an analytic black hole solution which asymptotes to the vacuum Lifshitz solution with z=3/2 at a specific value of the coupling constant. We analyze the thermodynamic behavior of this black hole and find that the black hole has zero entropy while non-zero temperature, which is very similar to the case of BTZ black holes in new massive gravity at a specific coupling. In addition, we find that the three dimensional Lifshitz black hole recently found by E. Ayon-Beato et al. has a negative entropy and mass when the Newton constant is taken to be positive.
We investigate string-like solutions in four dimensions based on Hov{r}ava-Lifshitz gravity. For a restricted class of solutions where the Cotton tensor vanishes, we find that the string-like solutions in Einstein gravity including the BTZ black stri
We show that three-dimensional massive gravity admits Lifshitz metrics with generic values of the dynamical exponent z as exact solutions. At the point z=3, exact black hole solutions which are asymptotically Lifshitz arise. These spacetimes are thre
In this paper, we present two new families of spatially homogeneous black hole solution for $z=4$ Hov{r}ava-Lifshitz Gravity equations in $(4+1)$ dimensions with general coupling constant $lambda$ and the especial case $lambda=1$, considering $beta=-
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
We present a detailed analysis of the construction of $z=2$ and $z eq2$ scale invariant Hov{r}ava-Lifshitz gravity. The construction procedure is based on the realization of Hov{r}ava-Lifshitz gravity as the dynamical Newton-Cartan geometry as well a