3,329 research outputs found
Absence of a Periodic Component in Quasar z-Distribution
Since the discovery of quasars in papers often appeared and appear the
assertions that the redshift quasar distribution includes a periodic component
with the period or 0.11. A statement of such kind, if it is
correct, may manifest the existence of a far order in quasar distribution in
cosmological time, that might lead to a fundamental revision all the
cosmological paradigm. In the present time there is a unique opportunity to
check this statement with a high precision, using the rich statictics of 2dF
and SDSS catalogues (about 85000 quasars). Our analysis indicates that the
periodic component in distribution of quasar redshifts is absent at high
confidence level
From Popov-Fedotov trick to universal fermionization
We show that Popov-Fedotov trick of mapping spin-1/2 lattice systems on
two-component fermions with imaginary chemical potential readily generalizes to
bosons with a fixed (but not limited) maximal site occupation number, as well
as to fermionic Hamiltonians with various constraints on the site Fock states.
In a general case, the mapping---fermionization---is on multi-component
fermions with many-body non-Hermitian interactions. Additionally, the
fermionization approach allows one to convert large many-body couplings into
single-particle energies, rendering the diagrammatic series free of large
expansion parameters; the latter is essential for the efficiency and
convergence of the diagrammatic Monte Carlo method.Comment: 4 pages, no figures (v2 contains some improvements; the most
important one is the generic complex chemical potential trick for
spins/bosons
Superfluid-Superfluid Phase Transitions in Two-Component Bose System
Depending on the Hamiltonian parameters, two-component bosons in an optical
lattice can form at least three different superfluid phases in which both
components participate in the superflow: a (strongly interacting) mixture of
two miscible superfluids (2SF), a paired superfluid vacuum (PSF), and (at a
commensurate total filling factor) the super-counter-fluid state (SCF). We
study universal properties of the 2SF-PSF and 2SF-SCF quantum phase transitions
and show that (i) they can be mapped onto each other, and (ii) their
universality class is identical to the (d+1)-dimensional normal-superfluid
transition in a single-component liquid. Finite-temperature 2SF-PSF(SCF)
transitions and the topological properties of 2SF-PSF(SCF) interfaces are also
discussed.Comment: 4pages, 2 figures, REVTe
Control of Spatially Heterogeneous and Time-Varying Cellular Reaction Networks: A New Summation Law
A hallmark of a plethora of intracellular signaling pathways is the spatial
separation of activation and deactivation processes that potentially results in
precipitous gradients of activated proteins. The classical Metabolic Control
Analysis (MCA), which quantifies the influence of an individual process on a
system variable as the control coefficient, cannot be applied to spatially
separated protein networks. The present paper unravels the principles that
govern the control over the fluxes and intermediate concentrations in spatially
heterogeneous reaction networks. Our main results are two types of the control
summation theorems. The first type is a non-trivial generalization of the
classical theorems to systems with spatially and temporally varying
concentrations. In this generalization, the process of diffusion, which enters
as the result of spatial concentration gradients, plays a role similar to other
processes such as chemical reactions and membrane transport. The second
summation theorem is completely novel. It states that the control by the
membrane transport, the diffusion control coefficient multiplied by two, and a
newly introduced control coefficient associated with changes in the spatial
size of a system (e.g., cell), all add up to one and zero for the control over
flux and concentration. Using a simple example of a kinase/phosphatase system
in a spherical cell, we speculate that unless active mechanisms of
intracellular transport are involved, the threshold cell size is limited by the
diffusion control, when it is beginning to exceed the spatial control
coefficient significantly.Comment: 19 pages, AMS-LaTeX, 6 eps figures included with geompsfi.st
Non-perturbative solutions in the electro-weak theory with condensate and the -quark mass
We apply Bogoliubov compensation principle to the gauge electro-weak
interaction to demonstrate a spontaneous generation of anomalous three-boson
gauge invariant effective interaction. The non-trivial solution of compensation
equations uniquely defines the form-factor of the anomalous interaction and
parameters of the theory including value of gauge electro-weak coupling
in satisfactory agreement with its experimental value. A possibility
of spontaneous generation of effective four-fermion interaction of heavy quarks
is also demonstrated. This interaction defines an equation for a scalar bound
state of heavy quarks which serve as a substitute for the elementary scalar
Higgs doublet. As a result we calculate the -quark mass
in satisfactory agreement with the experimental value. The results strongly
support idea of condensate as a source of the electro-weak symmetry
breaking.Comment: 16 pages, 5 figures. arXiv admin note: substantial overlap with
arXiv:1103.395
CDF Wjj anomaly as a non-perturbative effect of the electro-weak interaction
The recently reported CDF excess at in invariant mass
distribution of jet pairs accompanying -boson is tentatively interpreted as
a bound state of two decaying to quark-anti-quark pair. Non-perturbative
effects of EW interaction obtained by application of Bogoliubov compensation
approach lead to such bound state due to existence of anomalous three-boson
gauge-invariant effective interaction. The application of this scheme gives
satisfactory agreement with existing data without any adjusting parameter but
the bound state mass .Comment: 5 pages, 2 figure
Vortex-Phonon Interaction in the Kosterlitz-Thouless Theory
The "canonical" variables of the Kosterlitz-Thouless theory--fields
and , generally believed to stand for vortices
and phonons (or their XY equivalents, like spin waves, etc.) turn out to be
neither vortices and phonons, nor, strictly speaking, {\it canonical}
variables. The latter fact explains paradoxes of (i) absence of interaction
between and , and (ii) non-physical contribution of small vortex
pairs to long-range phase correlations. We resolve the paradoxes by explicitly
relating and to canonical vortex-pair and phonon variables.Comment: 4 pages, RevTe
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