We construct explicit examples of globally regular static, spherically symmetric solutions in general relativity with scalar and electromagnetic fields which describe traversable wormholes (with flat and AdS asymptotics) and regular black holes, in particular, black universes. A black universe is a nonsingular black hole where, beyond the horizon, instead of a singularity, there is an expanding, asymptotically isotropic universe. The scalar field in these solutions is phantom (i.e., its kinetic energy is negative), minimally coupled to gravity and has a nonzero self-interaction potential. The configurations obtained are quite diverse and contain different numbers of Killing horizons, from zero to four. This substantially widened the list of known structures of regular BH configurations. Such models can be of interest both as descriptions of local objects (black holes and wormholes) and as a basis for building nonsingular cosmological scenarios.

The Higgs boson of the Standard model is described by a set of off-diagonal components of the multidimensional metric tensor, as well as the gauge fields. In the low-energy limit, the basic properties of the Higgs boson are reproduced, including the shape of the potential and interactions with the gauge fields of the electroweak part of the Standard model.Comment: 11 pages, revtex4. Some wording changed, misprints corrected, 1 reference adde

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The well-known problem of wormholes in General Relativity (GR) is the necessity of exotic matter, violating the Weak Energy Condition (WEC), for their support. This problem looks easier if, instead of island-like configurations, one considers string-like ones, among them, cylindrically symmetric spacetimes with rotation. However, for cylindrical wormhole solutions, a problem is the lacking asymptotic flatness, making it impossible to observe their entrances as local objects in our universe. It was suggested to solve this problem by joining a wormhole solution to flat asymptotic regions at some surfaces [Formula: see text] and [Formula: see text] on different sides of the throat. The configuration then consists of three regions, the internal one containing a throat and two flat external ones. We discuss different kinds of source matter suitable for describing the internal regions of such models (scalar fields, isotropic and anisotropic fluids) and present two examples where the internal matter itself and the surface matter on both junction surfaces [Formula: see text] respect the WEC. In one of these models, the internal source is a stiff perfect fluid whose pressure is equal to its energy density, in the other, it is a special kind of anisotropic fluid. Both models are free from closed timelike curves. We thus obtain examples of regular twice asymptotically flat wormhole models in GR without exotic matter and without causality violations.

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