Gas of wormholes in Euclidean quantum field theory

We model the spacetime foam picture by a gas of wormholes in Euclidean field theory. It is shown that at large distances the presence of such a gas leads merely to a renormalization of mass and charge values. We also demonstrate that there exist a class of specific distributions of point-like wormholes which essentially change the ultraviolet behavior of Green functions and lead to finite quantum field theories.Comment: 11 pages, some misprints remove

Cosmological wormholes

We describe in details the procedure how the Lobachevsky space can be factorized to a space of the constant negative curvature filled with a gas of wormholes. We show that such wormholes have throat sections in the form of tori and are traversable and stable in the cosmological context. The relation of such wormholes to the dark matter phenomenon is briefly described. We also discuss the possibility of the existence of analogous factorizations for all types of homogeneous spaces

On the behavior of bosonic systems in the presence of topology fluctuations

The behavior of bosonic systems in the presence of space-time foam is analyzed within the simplistic model of a set of scalar fields on a flat background. We discuss the formula for the path integral which allows to account for the all possible topologies of spacetime. We show that the proper path integral originates from the parastatistics suggested first by H.S. Green and that it defines a cutoff for the field theory

Effective action for a free scalar field in the presence of spacetime foam

We model spacetime foam by a gas of virtual wormholes. For a free scalar field we derive the effective Lagrangian which accounts for the interaction with spacetime foam and contains two additional non-local terms. One term describes the scattering of scalar particles on virtual wormholes and explicitly reproduces the Pauli-Villars regularization procedure. The second term describes the back reaction of particles on the number density of wormholes and introduces a self-interaction between particles

Artificial Wormhole

It is shown that recently reported result by the OPERA Collaboration (arXive:1109.4897) of an early arrival time of muon neutrinos with respect to the speed of light in vacuum does not violate standard physical laws. We show that vacuum polarization effects in intensive external fields may form a wormhole-like object. The simplest theory of such an effect is presented and basic principles of formation of an artificial wormhole are also considered.Comment: minor corrections, references adde

On scattering of CMB radiation on wormholes: kinetic SZ-effect

The problem of scattering of CMB radiation on wormholes is considered. It is shown that a static gas of wormholes does not perturb the spectrum of CMB. In the first order by $v/c$ the presence of peculiar velocities gives rise to the dipole contribution in $\Delta T/T$, which corresponds to the well-known kinetic Sunyaev-Zel'dovich effect. In next orders there appears a more complicated dependence of the perturbed CMB spectrum on peculiar velocities. We also discuss some peculiar features of the scattering on a single wormhole.Comment: report at 14th Marcel Grossmann Meeting (Rome 2015

Spacetime foam

Spacetime foam is analyzed within the simplistic model of a set of scalar fields on a flat background. We suggest the formula for the path integral which allows to account for the all possible topologies of spacetime. We show that the proper path integral defines a cutoff for the field theory. The form of the cutoff is fixed by the field theory itself and has no free additional parameters. New features of the Feynman diagram technic are outlined and possible applications in quantum gravity are discussed.Comment: minor correction

On the possibility of the generation of an artificial wormhole

We model spacetime foam by a gas of virtual wormholes. Then applying an external field one may change the density of virtual wormholes and try to organize a wormhole-like structure in space. The relation between an additional distribution of virtual wormholes and the external field is considered for the homogeneous case. We show that the external fields suppress the density of virtual wormholes which sets an obstruction for creating an actual wormhole in a straightforward fashion. We also present a rough idea of a more complicated model for the artificial creation of a wormhole.Comment: text overlap with arXiv:1204.0351 but essential changes are added. arXiv admin note: text overlap with arXiv:1405.197

Wormhole as a possible accelerator of high-energy cosmic-ray particles

We present the simplest topological classification of wormholes and demonstrate that in open Friedmann models the genus $n\geq 1$ wormholes are stable and do not require the presence of exotic forms of matter, or any modification of general relativity. We show that such wormholes may also possess magnetic fields. It is found that when the wormhole gets into a galaxy or a surrounding region, it works as an accelerator of charged particles, or as a generator of synchrotron radiation. Estimates show that the threshold energy of such an accelerator may vary from sufficiently modest energies of the order of a few Gev, up to enormous energies of the Planckian order and even higher, depending on wormhole parameters.Comment: 8 pages, twocolumn, refs added, some misprints remove

Instability of fermions with respect to topology fluctuations

We extend our sum over topologies formula to fermions. We show that fermionic fields display an instability with respect to topology fluctuations. We present some phenomenological arguments for a modification of the action in the case of fermions and discuss possible applications