53,978 research outputs found
A method to search for correlations of ultra-high energy cosmic ray masses with the large scale structures in the local galaxy density field
One of the main goals of investigations using present and future giant
extensive air shower (EAS) arrays is the mass composition of ultra-high energy
cosmic rays (UHECRs). A new approach to the problem is presented, combining
analysis of arrival directions with the statistical test of the paired EAS
samples. An idea of the method is to search for possible correlations of UHECR
masses with their separate sources, for instance, if there are two sources in
different areas of the celestial sphere injecting different nuclei, but fluxes
are comparable so that arrival directions are isotropic, the aim is to reveal a
difference in the mass composition of CR fluxes. The method is based on a
non-parametric statistical test -- the Wilcoxon signed-rank routine -- which
does not depend on the populations fitting any parameterized distributions. Two
particular algorithms are proposed: first, using measurements of the depth of
EAS maximum position in the atmosphere; and second, relying on the age variance
of air showers initiated by different primary particles. The formulated method
is applied to the Yakutsk array data, in order to demonstrate the possibility
of searching for a difference in average mass composition of the two UHECR
sets, arriving particularly from the supergalactic plane and a complementary
region.Comment: Presented at International Symposium on Future Directions in UHECR
Physics, 13-16 February 2012 CERN. Accepted for publication in AP
A fine quantum mechanism of classical gravity
It is shown that screening the background of super-strong interacting
gravitons ensures the Newtonian attraction, if a part of single gravitons is
pairing and graviton pairs are destructed by collisions with a body. If the
considered quantum mechanism of classical gravity is realized in the nature,
than an existence of black holes contradicts to the equivalence principle. In
such the model, Newton's constant is proportional to where
is the Hubble constant, is an equivalent temperature of the graviton
background. The estimate of the Hubble constant is obtained for the Newtonian
limit: (or ).Comment: 9 pages, LaTeX. Contribution to the Tenth Marcel Grossmann Meeting
(MG10), 20-26 July 2003, Rio de Janeiro, Brazi
Lorentz symmetry violation due to interactions of photons with the graviton background
The average time delay of photons due to multiple interactions with gravitons
of the background is computed in a frame of the model of low-energy quantum
gravity by the author. The two variants of evaluation of the lifetime of a
virtual photon are considered: 1 on a basis of the uncertainties relation
(it is a common place in physics of particles) and 2 using a conjecture
about constancy of the proper lifetime of a virtual photon. It is shown that in
the first case Lorentz violation is negligible: the ratio of the average time
delay of photons to their propagation time is equal approximately to
; in the second one (with a new free parameter of the model), the
time-lag is proportional to the difference , where
are initial energies of photons, and more energetic photons
should arrive later, also as in the first case. The effect of graviton pairing
is taken into account, too.Comment: 7 pages, no figure, Late
How to verify the redshift mechanism of low-energy quantum gravity
In the model of low-energy quantum gravity by the author, the redshift
mechanism is quantum and local, and it is not connected with any expansion of
the Universe. A few possibilities to verify its predictions are considered
here: the specialized ground-based laser experiment; a deceleration of massive
bodies and the Pioneer anomaly; a non-universal character of the Hubble diagram
for soft and hard radiations; galaxy/quasar number counts.Comment: 6 pages, 3 figures, Latex. In the Proceedings of the Int. conference
Problems of Practical Cosmology, 23-27 June 2008, Saint Petersburg, Russi
Superspace without torsion and the composite fundamental fermions
(N=2)-superspace without torsion is described, which is equivalent to an
8-space with a discrete internal subspace. A number and a character of ties
determine now an internal symmetry group, while in the supersymmetrical models
this one is determined by an extension degree N. Such a model can be
constructed for no less than 4 generations of the two-component fundamental
fermions. Analogues of the Higgs fields appear in the model naturally after
transition to the Grassmannian extra coordinates. The connection between
discrete and continues internal symmetries of the model is discussed. If one
considers gravity as embedding the curved 4-space into a 12-dimensional flat
space, a U(1)-symmetry appears transformations of which should be connected
with the ones of SU(2)-group. If super-strong interacting gravitons are
constituents of the composite fermions, all this may open us another way to
unify the known interactions. The main feature of this new approach may be the
external see of gravitons underlying an internal structure of particles; the
lack of any divergencies would be due the Planckian spectrum of external
gravitons.Comment: 5 pages, Late
- …
