Sergey V. Sushkov

Wormholes supported by a phantom energy

We extend the notion of phantom energy, which is generally accepted for homogeneously distributed matter with w<-1 in the universe, on inhomogeneous spherically symmetric spacetime configurations. A spherically symmetric distribution of phantom energy is shown to be able to support the existence of static wormholes. We find an exact solution describing a static spherically symmetric wormhole with phantom energy and show that a spatial distribution of the phantom energy is mainly restricted by the vicinity of the wormholes throat. The maximal size of the spherical region, surrounding the throat and containing the most part of the phantom energy, depends on the equation-of-state parameter w and cannot exceed some upper limit.

Self-Consistent Wormhole Solutions of Semiclassical Gravity

We present the first results of a self-consistent solution of the semiclassical Einstein field equations corresponding to a Lorentzian wormhole coupled to a quantum scalar field. The specific solution presented here represents a wormhole connecting two asymptotically spatially flat regions. In general, the diameter of the wormhole throat, in units of the Planck length, can be arbitrarily large, depending on the values of the scalar coupling

Cosmological Evolution of a Ghost Scalar Field

\ensuremath{\xi}

Ground state energy in a wormhole space-time

and the boundary values for the shape and redshift functions. In all cases we have considered, there is a fine structure in the form of Planck-scale oscillations or ripples superimposed on the solutions.

Chronology protection and quantized fields: Complex automorphic scalar field in Misner space

We consider a scalar field with a negative kinetic term minimally coupled to gravity. We obtain an exact non-static spherically symmetric solution which describes a wormhole in a cosmological setting. The wormhole is shown to connect two homogeneous spatially flat universes expanding with acceleration. Depending on the wormholes mass parameter m the acceleration can be constant (the de Sitter case) or infinitely growing.

Wormholes supported by a kink-like configuration of a scalar field

The ground state energy of the massive scalar field with non-conformal coupling

The Casimir effect in a wormhole spacetime

\xi

Vacuum polarization of a scalar field in wormhole spacetimes

on the short-throat flat-space wormhole background is calculated by using zeta renormalization approach. We discuss the renormalization and relevant heat kernel coefficients in detail. We show that the stable configuration of wormholes can exist for

Quantum complex scalar field in two-dimensional spacetime with closed timelike curves and a time-machine problem

\xi > 0.123

Black Hole in Thermal Equilibrium with a Spin-2 Quantum Field

. In particular case of massive conformal scalar field with