1,189 research outputs found
On topological bias of discrete sources in the gas of wormholes
The model of space in the form of a static gas of wormholes is considered. It
is shown that the scattering on such a gas gives rise to the formation of a
specific diffuse halo around every discrete source. Properties of the halo are
determined by the distribution of wormholes in space and the halo has to be
correlated with the distribution of dark matter. This allows to explain the
absence of dark matter in intergalactic gas clouds. Numerical estimates for
parameters of the gas of wormholes are also obtained
Bilinear identities on Schur symmetric functions
A series of bilinear identities on the Schur symmetric functions is obtained
with the use of Pluecker relations.Comment: Accepted to Journal of Nonlinear Mathematical Physics. A reference to
a connected result is adde
Effects related to spacetime foam in particle physics
It is found that the existence of spacetime foam leads to a situation in
which the number of fundamental quantum bosonic fields is a variable quantity.
The general aspects of an exact theory that allows for a variable number of
fields are discussed, and the simplest observable effects generated by the foam
are estimated. It is shown that in the absence of processes related to
variations in the topology of space, the concept of an effective field can be
reintroduced and standard field theory can be restored. However, in the
complete theory the ground state is characterized by a nonvanishing particle
number density. From the effective-field standpoint, such particles are "dark".
It is assumed that they comprise dark matter of the universe. The properties of
this dark matter are discussed, and so is the possibility of measuring the
quantum fluctuation in the field potentials.Comment: 18 pages, minor corrections added to the published varian
Covariant Formulation of the Invariant Measure for the Mixmaster Dynamics
We provide a Hamiltonian analysis of the Mixmaster Universe dynamics showing
the covariant nature of its chaotic behavior with respect to any choice of time
variable. We construct the appropriate invariant measure for the system (which
relies on the existence of an ``energy-like'' constant of motion) without
fixing the time gauge, i.e. the corresponding lapse function. The key point in
our analysis consists of introducing generic Misner-Chitr\'e-like variables
containing an arbitrary function, whose specification allows one to set up the
same dynamical scheme in any time gauge.Comment: 11 pages, 1 figur
Quasi-Isotropization of the Inhomogeneous Mixmaster Universe Induced by an Inflationary Process
We derive a ``generic'' inhomogeneous ``bridge'' solution for a cosmological
model in the presence of a real self-interacting scalar field. This solution
connects a Kasner-like regime to an inflationary stage of evolution and
therefore provides a dynamical mechanism for the quasi-isotropization of the
universe. In the framework of a standard Arnowitt-Deser-Misner Hamiltonian
formulation of the dynamics and by adopting Misner-Chitr\`e-like variables, we
integrate the Einstein-Hamilton-Jacobi equation corresponding to a ``generic''
inhomogeneous cosmological model whose evolution is influenced by the coupling
with a bosonic field, expected to be responsible for a spontaneous symmetry
breaking configuration. The dependence of the detailed evolution of the
universe on the initial conditions is then appropriately characterized.Comment: 17 pages, no figure, to appear on PR
- …