2,548 research outputs found

### Child universes UV regularization?

It is argued that high energy density excitations, responsible for UV
divergences in quantum field theories, including quantum gravity, are likely to
be the source of child universes which carry them out of the original space
time. This decoupling prevents these high UV excitations from having any
influence on physical amplitudes. Child universe production could therefore be
responsible for UV regularization in quantum field theories which takes into
account gravitational effects. Also child universe production in the last
stages of black hole evaporation, the prediction of absence of tranplanckian
primordial perturbations, connection to the minimum length hypothesis and in
particular connection to the maximal curvature hypothesis are discussed.Comment: 6 pages, RevTex, discussion to the maximum curvature hypothesis adde

### Wormholes and Child Universes

Evidence to the case that classical gravitation provides the clue to make
sense out of quantum gravity is presented. The key observation is the existence
in classical gravitation of child universe solutions or "almost" solutions,
"almost" because of some singularity problems. The difficulties of these child
universe solutions due to their generic singularity problems will be very
likely be cured by quantum effects, just like for example "almost" instanton
solutions are made relevant in gauge theories with breaking of conformal
invariance. Some well motivated modifcations of General Relativity where these
singularity problems are absent even at the classical level are discussed. High
energy density excitations, responsible for UV divergences in quantum field
theories, including quantum gravity, are likely to be the source of child
universes which carry them out of the original space time. This decoupling
could prevent these high UV excitations from having any influence on physical
amplitudes. Child universe production could therefore be responsible for UV
regularization in quantum field theories which take into account
semiclassically gravitational effects. Child universe production in the last
stages of black hole evaporation, the prediction of absence of tranplanckian
primordial perturbations, connection to the minimum length hypothesis and in
particular the connection to the maximal curvature hypothesis are discussed.
Some discussion of superexcited states in the case these states are Kaluza
Klein excitations is carried out. Finally, the posibility of obtaining "string
like" effects from the wormholes associated with the child universes is
discussed.Comment: Talk presented at the IWARA 2009 Conference, Maresias, Brazil,
October 2009, accepted for publication in the proceedings, World Scientific
format, 8 page

### Study of the spring and autumn daemon-flux maxima at the Baksan Neutrino Observatory

Detection of daemons in low-background conditions in September 2005 and March
2006 has provided evidence for the expected to occur at that times maxima in
the flux of daemons with V ~ 10-15 km s-1, which hit the Earth from near-Earth,
almost circular heliocentric orbits. The ability of some FEU-167-1 PM tubes
with a thicker inner Al coating to detect directly daemon passage through them
has also been demonstrated, an effect increasing ~100-fold the detector
efficiency. As a result, the daemon flux recorded at the maxima was increased
from ~10-9 to ~10-7 cm-2 s-1. The intensity and direction of the flux during
maxima depend on the time of day and latitude of observations (therefore,
synchronous measurements in the Northern and Southern Earth's hemispheres are
desirable). All the experimental results obtained either support the
conclusions following from the daemon paradigm or find a simple interpretation
within it.Comment: 15 pages, including 8 figures and 3 table

### Unitary quantization and para-Fermi statistics of order two

A connection between a unitary quantization scheme and para-Fermi statistics
of order 2 is considered. An appropriate extension of Green's ansatz is
suggested. This extension allows one to transform bilinear and trilinear
commutation relations for the annihilation and creation operators of two
different para-Fermi fields $\phi_{a}$ and $\phi_{b}$ into identity. The way of
incorporating para-Grassmann numbers $\xi_{k}$ into a general scheme of
uniquantization is also offered. For parastatistics of order 2 a new fact is
revealed, namely, the trilinear relations containing both the para-Grassmann
variables $\xi_{k}$ and the field operators $a_{k}$, $b_{m}$ under a certain
invertible mapping go over into the unitary equivalent relations, where
commutators are replaced by anticommutators and vice versa. It is shown that
the consequence of this circumstance is the existence of two alternative
definitions of the coherent state for para-Fermi oscillators. The Klein
transformation for Green's components of the operators $a_{k}$, $b_{m}$ is
constructed in an explicit form that enables us to reduce the initial
commutation rules for the components to the normal commutation relations of
ordinary Fermi fields. A nontrivial connection between trilinear commutation
relations of the unitary quantization scheme and so-called Lie-supertriple
system is analysed. A brief discussion of the possibility of embedding the
Duffin-Kemmer-Petiau theory into the unitary quantization scheme is provided.Comment: 44 pages, the version published in J. Exp. Theor. Phy

### A non-singular black hole model as a possible end-product of gravitational collapse

In this paper we present a non-singular black hole model as a possible
end-product of gravitational collapse. The depicted spacetime which is type
[II,(II)], by Petrov classification, is an exact solution of the Einstein
equations and contains two horizons. The equation of state in the radial
direction, is a well-behaved function of the density and smoothly reproduces
vacuum-like behavior near r=0 while tending to a polytrope at larger r, low
density, values. The final equilibrium configuration comprises of a de
Sitter-like inner core surrounded by a family of 2-surfaces of matter fields
with variable equation of state. The fields are all concentrated in the
vicinity of the radial center r=0. The solution depicts a spacetime that is
asymptotically Schwarzschild at large r, while it becomes de Sitter-like for
vanishing r. Possible physical interpretations of the macro-state of the black
hole interior in the model are offered. We find that the possible state admits
two equally viable interpretations, namely either a quintessential intermediary
region or a phase transition in which a two-fluid system is in both dynamic and
thermodynamic equilibrium. We estimate the ratio of pure matter present to the
total energy and in both (interpretations) cases find it to be virtually the
same, being 0.83. Finally, the well-behaved dependence of the density and
pressure on the radial coordinate provides some insight on dealing with the
information loss paradox.Comment: 12 Pages, 1 figure. Accepted for publication in Phys. Rev.

### On the possibilities of large-scale radio and fiber optics detectors in cosmic rays

Different variants of radio and fiber optics detectors for registration of super high energy cascades in the atmosphere and in dense media are discussed. Particularly the possibilities for investigation of quasi horizontal cosmic ray showers (CRS) and simulated muons from these CRS with the help of radio detectors and fiber optics detectors located on the ice surface are considered

### Hamiltonian formalism for Fermi excitations in a plasma with a non-Abelian interaction

The Hamiltonian theory for the collective longitudinally polarized colorless
gluon excitations (plasmons) and for collective quark-antiquark excitations
with abnormal relation between chirality and helicity (plasminos) in a
high-temperature quark-gluon plasma (QGP) is developed. For this purpose,
Zakharov's formalism for constructing the wave theory in nonlinear media with
dispersion is used. A generalization of the Poisson superbracket involving both
commuting and anticommuting variables to the case of a continuous medium is
performed and the corresponding Hamilton equations are presented. The canonical
transformations including simultaneously both bosonic and fermionic degrees of
freedom of the collective excitations in QGP are discussed and a complete
system of the canonicity conditions for these transformations is written out.
An explicit form of the effective fourth-order Hamiltonians describing the
elastic scattering of plasmino off plasmino and plasmino off plasmon is found
and the Boltzmann type kinetic equations describing the processes of elastic
scattering are obtained. A detailed comparison of the effective amplitudes
defined within the (pseudo)classical Hamiltonian theory, with the corresponding
matrix elements calculated early in the framework of high-temperature quantum
chromodynamics in the so-called hard thermal loop approximation is performed.
This enables one to obtain, in particular, an explicit form of the vertex and
coefficient functions in the effective amplitudes and in the canonical
transformations, correspondingly, and also to define the validity of a purely
pseudoclassical approach in the Hamiltonian description of the dynamics of a
quark-gluon plasma. The problem of determining the higher-order coefficient
functions in the canonical transformations of fermionic and bosonic normal
variables is considered.Comment: 69 pages, 2 figures, typos corrected and references adde

### Hamiltonian formalism for Bose excitations in a plasma with a non-Abelian interaction I: plasmon -- hard particle scattering

The Hamiltonian theory for the collective longitudinally polarized gluon
excitations (plasmons) coupling with classical high-energy test color-charged
particle propagating through a high-temperature gluon plasma is developed. A
generalization of the Lie-Poisson bracket to the case of a continuous medium
involving bosonic normal field variable
$a^{\phantom{\ast}\!\!a}_{\hspace{0.03cm}{\bf k}}$ and a non-Abelian color
charge $Q^{\hspace{0.03cm}a}$ is performed and the corresponding Hamilton
equations are presented. The canonical transformations including simultaneously
both bosonic degrees of freedom of the soft collective excitations and degree
of freedom of hard test particle connecting with its color charge in the hot
gluon plasma are written out. A complete system of the canonicity conditions
for these transformations is derived. The notion of the plasmon number density
${\mathcal N}^{a\hspace{0.03cm}a^{\prime}_{\phantom{1}}\!}_{{\bf k}}$, which is
a nontrivial matrix in the color space, is introduced. An explicit form of the
effective fourth-order Hamiltonian describing elastic scattering of plasmon off
a hard color particle is found and the self-consistent system of Boltzmann type
kinetic equations taking into account the time evolution of the mean value of
the color charge of the hard particle is obtained. On the basis of these
equations, a model problem of interaction of two infinitly narrow wave packets
is considered. A system of nonlinear first-order ordinary differential
equations defining the dynamics of the interaction of the colorless $N^{l}_{\bf
k}$ and color $W^{l}_{\bf k}$ components of the plasmon number density is
derived. The problem of determining the third- and fourth-order coefficient
functions entering into the canonical transformations of the original bosonic
variable $a^{\phantom{\ast}\!\!a}_{{\bf k}}$ and color charge
$Q^{\hspace{0.03cm}a}$ is discussed.Comment: 57 pages, 5 figure

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