Search

We present dynamic wormhole solutions in the framework of Lovelock gravity with compact extra dimensions. Calculations are done in D = 7, although they can be extended to an arbitrary number of extra dimensions. It is shown that as the wormhole inflates with the three-dimensional space, the extra dimensions deflate to very small, yet nonvanishing scales. The weak energy condition is shown to hold for certain ranges of the free parameters, everywhere, down to the throat of the wormhole. [ABSTRACT FROM AUTHOR]

We construct quartic quasitopological gravity, a theory of gravity containing terms quartic in the curvature that yields second-order differential equations in the spherically symmetric case. Up to a term proportional to the quartic term in Lovelock gravity we find a unique solution for this quartic case, valid in any dimensionality larger than 4 except 8. This case is the highest degree of curvature coupling for which explicit black hole solutions can be constructed, and we obtain and analyze the various black hole solutions that emerge from the field equations in (n + 1) dimensions. We discuss the thermodynamics of these black holes and compute their entropy as a function of the horizon radius. We then make some general remarks about K-th order quasitopological gravity, and point out that the basic structure of the solutions will be the same in any dimensionality for general K apart from particular cases. [ABSTRACT FROM AUTHOR]