Black Holes
No TL;DR found
Abstract
Multidimensional cosmological, static spherically symmetric and Euclidean configurations are described in a unified way for gravity interacting with several dilatonic fields and antisymmetric forms, associated with electric and magnetic p -branes. Exact solutions are obtained when certain vectors, built from the input parameters of the model, are either orthogonal in the minisuperspace, or form mutually orthogonal subsystems. Some properties of black hole solutions are indicated, in particular, a no-hair-type theorem and restrictions emerging in models with multiple times. From the non-existence of Lorentzian wormholes, a universal restriction is obtained, applicable to orthogonal or block-orthogonal subsystems of any p -brane systems. Euclidean wormhole solutions are found, their actions and radii are explicitly calculated.