title:
Elastic properties of vanadium pentoxide aggregates and topological
  defects

abstract:
  We study the aqueous solution of vanadium pentoxide by using topology
methods. The experiments by Zocher, Kaznacheev, and Dogic exhibited, that in
the sol phases of $V_2O_5-H_2O$, the tactoid droplets of $V_2O_5$ can coalesce.
In the magnetic field, this effect is associated with a gauge field action,
viz. we consider coalescence (in the topologically more convenient term,
"junction") of droplets as annihilation of topological defects, concerning with
the tactoid geometry. We have shown, that in the magnetic field, the tactoid
junction is mainly caused by non-Abelian monopoles (vortons), whereas the
Abelian defects almost do not annihilate. Taking into account this annihilation
mechanism, the estimations of time-aging of the $V_2O_5-H_2O$ sols may be
specified


title:
Non-Associativity of Lorentz Transformation and Associative Reflection
  Symmetric Transformation

abstract:
  Each of the two moving observers observes the relative velocity of the other.
The two velocities should be equal and opposite. We have shown that this
relativistic requirement is not fulfilled by Lorentz transformation. We have
also shown that the reason is that Lorentz transformation is not associative.
Reciprocal symmetric transformation is associative and fulfills relativistic
requirements.


title: Jamming dynamics in grain mixtures : An extended hydrodynamic approach

abstract:
  We study jamming in granular mixtures from the novel point of view of
extended hydrodynamics. Using a hard sphere binary mixture model we predict
that a few large grains are expected to get caged more effectively in a matrix
of small grains compared to a few small grains in a matrix of larger ones. A
similar effect has been experimentally seen in the context of colloidal
mixtures.


title: Path Distinguishability in Double Scattering of Light by Atoms

abstract:
  Wave-particle duality finds a natural application for electrons or light
propagating in disordered media where coherent corrections to transport are
given by two-wave interference. For scatterers with internal degrees of
freedom, these corrections are observed to be much smaller than would be
expected for structureless scatterers. By examining the basic example of the
scattering of one photon by two spin-1/2 atoms--a case-study for coherent
backscattering--we demonstrate that the loss of interference strength is
associated with which-path information stored by the scattering atoms.


title:
Constraints on transmission, dispersion, and density of states in
  dielectric multilayers and stepwise potential barriers with arbitrary layer
  arrangement

abstract:
  Normal-incidence transmission and dispersion properties of optical
multilayers and one-dimensional stepwise potential barriers in the
non-tunneling regime are analytically investigated. The optical paths of every
constituent layer in a multilayer structure, as well as the parameters of every
step of the stepwise potential barrier, are constrained by a generalized
quarter-wave condition. No other restrictions on the structure geometry is
imposed, i.e., the layers are arranged arbitrarily. We show that the density of
states (DOS) spectra of the multilayer or barrier in question are subject to
integral conservation rules similar to the Barnett-Loudon sum rule but ocurring
within a finite frequency or energy interval. In the optical case, these
frequency intervals are regular. For the potential barriers, only non-periodic
energy intervals can be present in the spectrum of any given structure, and
only if the parameters of constituent potential steps are properly chosen.
  Abstract The integral conservation relations derived analytically have also
been verified numerically. The relations can be used in dispersion-engineered
multilayer-based devices, e.g., ultrashort pulse compressors or ultracompact
optical delay lines, as well as to design multiple-quantum-well electronic
heterostructures with engineered DOS.


title:
Electromagnetic Casimir densities for a wedge with a coaxial cylindrical
  shell

abstract:
  Vacuum expectation values of the field square and the energy-momentum tensor
for the electromagnetic field are investigated for the geometry of a wedge with
a coaxal cylindrical boundary. All boundaries are assumed to be perfectly
conducting and both regions inside and outside the shell are considered. By
using the generalized Abel-Plana formula, the vacuum expectation values are
presented in the form of the sum of two terms. The first one corresponds to the
geometry of the wedge without the cylindrical shell and the second term is
induced by the presence of the shell. The vacuum energy density induced by the
shell is negative for the interior region and is positive for the exterior
region. The asymptotic behavior of the vacuum expectation values are
investigated in various limiting cases. It is shown that the vacuum forces
acting on the wedge sides due to the presence of the cylindrical boundary are
always attractive.


title: Progenitors of Long Gamma-ray Bursts

abstract:
  Pinpointing the progenitors of long duration gamma-ray bursts (LGRBs) remains
an extremely important question, although it is now clear that at least a
fraction of LGRBs originate in the core collapse of massive stars in type Ic
supernovae, the pathways to the production of these stars, and their initial
masses, remain uncertain. Rotation is thought to be vital in the creation of
LGRBs, and it is likely that black hole creation is also necessary. We suggest
that these two constraints can be met if the GRB progenitors are very massive
stars (>20 solar masses) and are formed in tight binary systems. Using simple
models we compare the predictions of this scenario with observations and find
that the location of GRBs on their host galaxies are suggestive of
main-sequence masses in excess of 20 solar masses, while 50% of the known
compact binary systems may have been sufficiently close to have had the
necessary rotation rates for GRB creation. Thus, massive stars in compact
binaries are a likely channel for at least some fraction of LGRBs.


title: Causal vs. Analytic constraints on anomalous quartic gauge couplings

abstract:
  We derive one loop constraints on the anomalous quartic gauge couplings using
a general non-forward dispersion relation for the elastic scattering amplitude
of two longitudinally polarized vector bosons. We compare this result with
another one derived by the assumption that the underlying theory satisfies the
causality principle of Special Relativity and show that this latter is more
constraining.


title: Classical Information Capacity of the Bosonic Broadcast Channel

abstract:
  We show that when coherent-state encoding is employed in conjunction with
coherent detection, the Bosonic broadcast channel is equivalent to a classical
degraded Gaussian broadcast channel whose capacity region is dual to that of
the classical Gaussian multiple-access channel. We further show that if a
minimum output-entropy conjecture holds true, then the ultimate classical
information capacity of the Bosonic broadcast channel can be achieved by a
coherent-state encoding. We provide some evidence in support of the conjecture.


title:
Interplay of Anisotropy and Disorder in the Doping-Dependent Melting and
  Glass Transitions of Vortices in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$

abstract:
  We study the oxygen doping dependence of the equilibrium first-order melting
and second-order glass transitions of vortices in
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. Doping affects both anisotropy and
disorder. Anisotropy scaling is shown to collapse the melting lines only where
thermal fluctuations are dominant. Yet, in the region where disorder breaks
that scaling, the glass lines are still collapsed. A quantitative fit to
melting and replica symmetry breaking lines of a 2D Ginzburg-Landau model
further reveals that disorder amplitude weakens with doping, but to a lesser
degree than thermal fluctuations, enhancing the relative role of disorder.


title:
Growth window and possible mechanism of millimeter-thick single-walled
  carbon nanotube forests

abstract:
  Our group recently reproduced the water-assisted growth method, so-called
"super growth", of millimeter-thick single-walled carbon nanotube (SWNT)
forests by using C2H4/ H2/ H2O/ Ar reactant gas and Fe/ Al2O3 catalyst. In this
current work, a parametric study was carried out on both reaction and catalyst
conditions. Results revealed that a thin Fe catalyst layer (about 0.5 nm)
yielded rapid growth of SWNTs only when supported on Al2O3, and that Al2O3
support enhanced the activity of Fe, Co, and Ni catalysts. The growth window
for the rapid SWNT growth was narrow, however. Optimum amount of added H2O
increased the SWNT growth rate but further addition of H2O degraded both the
SWNT growth rate and quality. Addition of H2 was also essential for rapid SWNT
growth, but again, further addition decreased both the SWNT growth rate and
quality. Because Al2O3 catalyzes hydrocarbon reforming, Al2O3 support possibly
enhances the SWNT growth rate by supplying the carbon source to the catalyst
nanoparticles. The origin of the narrow window for rapid SWNT growth will also
be discussed.


title: Nonlocal interactions versus viscosity in turbulence

abstract:
  It is shown that nonlocal interactions determine energy spectrum in isotropic
turbulence at small Reynolds numbers. It is also shown that for moderate
Reynolds numbers the bottleneck effect is determined by the same nonlocal
interactions. Role of the large and small scales covariance at the nonlocal
interactions and in energy balance has been investigated. A possible
hydrodynamic mechanism of the nonlocal solution instability at large scales has
been briefly discussed. A quantitative relationship between effective strain of
the nonlocal interactions and viscosity has been found. All results are
supported by comparison with the data of experiments and numerical simulations.


title: Quantum radiative corrections to slow-roll inflation

abstract:
  We consider the nonminimally coupled lambda phi^4 scalar field theory in de
Sitter space and construct the renormalization group improved renormalized
effective theory at the one-loop level. Based on the corresponding quantum
Friedmann equation and the scalar field equation of motion, we calculate the
quantum radiative corrections to the scalar spectral index n_s, gravitational
wave spectral index n_g and the ratio r of tensor to scalar perturbations. When
compared with the standard (tree-level) values, we find that the quantum
contributions are suppressed by lambda N^2 where N denotes the number of
e-foldings. Hence there is an N^2 enhancement with respect to the naive
expectation, which is due to the infrared enhancement of scalar vacuum
fluctuations characterising de Sitter space. Since observations constrain
lambda to be very small lambda ~ 10^(-12) and N ~ 50-60, the quantum
corrections in this inflationary model are unobservably small.


title:
Ab initio wavefunction based methods for excited states in solids:
  correlation corrections to the band structure of ionic oxides

abstract:
  Ab initio wavefunction based methods are applied to the study of electron
correlation effects on the band structure of oxide systems. We choose MgO as a
prototype closed-shell ionic oxide. Our analysis is based on a local
Hamiltonian approach and performed on finite fragments cut from the infinite
solid. Localized Wannier functions and embedding potentials are obtained from
prior periodic Hartree-Fock (HF) calculations. We investigate the role of
various electron correlation effects in reducing the HF band gap and modifying
the band widths. On-site and nearest-neighbor charge relaxation as well as
long-range polarization effects are calculated. Whereas correlation effects are
essential for computing accurate band gaps, we found that they produce smaller
changes on the HF band widths, at least for this material. Surprisingly, a
broadening effect is obtained for the O 2p valence bands. The ab initio data
are in good agreement with the energy gap and band width derived from
thermoreflectance and x-ray photoemission experiments. The results show that
the wavefunction based approach applied here allows for well controlled
approximations and a transparent identification of the microscopic processes
which determine the electronic band structure.


title:
Abundances in intermediate-mass AGB stars undergoing third dredge-up and
  hot-bottom burning

abstract:
  High dispersion near-infrared spectra have been taken of seven
highly-evolved, variable, intermediate-mass (4-6 Msun) AGB stars in the LMC and
SMC in order to look for C, N and O variations that are expected to arise from
third dredge-up and hot-bottom burning. The pulsation of the objects has been
modelled, yielding stellar masses, and spectral synthesis calculations have
been performed in order to derive abundances from the observed spectra. For two
stars, abundances of C, N, O, Na, Al, Ti, Sc and Fe were derived and compared
with the abundances predicted by detailed AGB models. Both stars show very
large N enhancements and C deficiencies. These results provide the first
observational confirmation of the long-predicted production of primary nitrogen
by the combination of third dredge-up and hot-bottom burning in
intermediate-mass AGB stars. It was not possible to derive abundances for the
remaining five stars: three were too cool to model, while another two had
strong shocks in their atmospheres which caused strong emission to fill the
line cores and made abundance determination impossible. The latter occurrence
allows us to predict the pulsation phase interval during which observations
should be made if successful abundance analysis is to be possible.


title:
A practical guide to stochastic simulations of reaction-diffusion
  processes

abstract:
  A practical introduction to stochastic modelling of reaction-diffusion
processes is presented. No prior knowledge of stochastic simulations is
assumed. The methods are explained using illustrative examples. The article
starts with the classical Gillespie algorithm for the stochastic modelling of
chemical reactions. Then stochastic algorithms for modelling molecular
diffusion are given. Finally, basic stochastic reaction-diffusion methods are
presented. The connections between stochastic simulations and deterministic
models are explained and basic mathematical tools (e.g. chemical master
equation) are presented. The article concludes with an overview of more
advanced methods and problems.


title: Non-linear electromagnetic response of graphene

abstract:
  It is shown that the massless energy spectrum of electrons and holes in
graphene leads to the strongly non-linear electromagnetic response of this
system. We predict that the graphene layer, irradiated by electromagnetic
waves, emits radiation at higher frequency harmonics and can work as a
frequency multiplier. The operating frequency of the graphene frequency
multiplier can lie in a broad range from microwaves to the infrared.


title:
Ellipsoidal Oscillations Induced by Substellar Companions: A Prospect
  for the Kepler Mission

abstract:
  Hundreds of substellar companions to solar-type stars will be discovered with
the Kepler satellite. Kepler's extreme photometric precision gives access to
low-amplitude stellar variability contributed by a variety of physical
processes. We discuss in detail the periodic flux modulations arising from the
tidal force on the star due to a substellar companion. An analytic expression
for the variability is derived in the equilibrium-tide approximation. We
demonstrate analytically and through numerical solutions of the linear,
nonadiabatic stellar oscillation equations that the equilibrium-tide formula
works extremely well for stars of mass <1.4 Msun with thick surface convection
zones. More massive stars with largely radiative envelopes do not conform to
the equilibrium-tide approximation and can exhibit flux variations $\ga$10
times larger than naive estimates. Over the full range of stellar masses
considered, we treat the oscillatory response of the convection zone by
adapting a prescription that A. J. Brickhill developed for pulsating white
dwarfs. Compared to other sources of periodic variability, the ellipsoidal
lightcurve has a distinct dependence on time and system parameters. We suggest
that ellipsoidal oscillations induced by giant planets may be detectable from
as many as ~100 of the 10^5 Kepler target stars. (Abridged)


title:
Motor driven microtubule shape fluctuations - force from within the
  lattice

abstract:
  We develop a general theory of microtubule (MT) deformations by molecular
motors generating internal force doublets within the MT lattice. We describe
two basic internal excitations, the S and V shape, and compare them with
experimental observations from literature. We explain the special role of
tubulin vacancies and the dramatic deformation amplifying effect observed for
katanin acting at positions of defects. Experimentally observed shapes are used
to determine the ratio of MT shear and stretch moduli ($\approx
6\times10^{-5}$) and to estimate the forces induced in the MT lattice by
katanin (10's of pN). For many motors acting on a single MT we derive
expressions for the end-to-end distance reduction and provide criteria for
dominance of this new effect over thermal fluctuations. We conclude that
molecular motors if acting cooperatively can ''animate'' MTs from within the
lattice and induce slack even without cross-bridging to other structures, a
scenario very much reminiscent of the motor driven axoneme.


title: Bone Cancer Rates in Dinosaurs Compared with Modern Vertebrates

abstract:
  Data on the prevalence of bone cancer in dinosaurs is available from past
radiological examination of preserved bones. We statistically test this data
for consistency with rates extrapolated from information on bone cancer in
modern vertebrates, and find that there is no evidence of a different rate.
Thus, this test provides no support for a possible role of ionizing radiation
in the K-T extinction event.


title:
Effective Lagrangian for the $\chi^{+}_j \chi^{-}_kH^{0}_l$ interaction
  in the minimal supersymmetric standard model and neutral Higgs decays

abstract:
  We extend previous analyses of the supersymmetric loop correction to the
neutral Higgs couplings to include the coupling $\chi^{+}_j \chi^{-}_kH^{0}_l$.
The analysis completes the previous analyses where similar corrections were
computed for the $\bar{\tau} \tau H^{0}_l$, $\bar{b} b H^{0}_l$, $\bar{c} c
H^{0}_l$ and for $\bar{t} t H^{0}_l$ couplings within the minimal
supersymmetric standard model. The effective one loop Lagrangian is then
applied to the computation of the neutral Higgs decays. The sizes of the
supersymmetric loop corrections of the neutral Higgs decay widths into
$\chi^{+}_i \chi^{-}_j$ ($i=1,2$; $j=1,2$) are investigated and the
supersymmetric loop correction is found to be in the range of $7\sim15%$ in
significant regions of the parameter space. By including the loop corrections
of the other decay channels $\bar{b} b$, $\bar{t} t$, $\bar{\tau} \tau$,
$\bar{c} c$, and $\chi^0_i \chi^0_j$ ($i=1-4$; $j=1-4$), the corrections to
branching ratios for $H^{0}_l\to \chi^{+}_i \chi^{-}_j$ can reach as high as
40%.
  The effects of CP phases on the branching ratio are also investigated.


title: Finite Representations of the braid group commutator subgroup

abstract:
  We study the representations of the commutator subgroup K_{n} of the braid
group B_{n} into a finite group . This is done through a symbolic dynamical
system. Some experimental results enable us to compute the number of subgroups
of K_{n} of a given (finite) index, and, as a by-product, to recover the well
known fact that every representation of K_{n} into S_{r}, with n > r, must be
trivial.


title:
Thermal inertia of near-Earth asteroids and implications for the
  magnitude of the Yarkovsky effect

abstract:
  Thermal inertia determines the temperature distribution over the surface of
an asteroid and therefore governs the magnitude the Yarkovsky effect. The
latter causes gradual drifting of the orbits of km-sized asteroids and plays an
important role in the delivery of near-Earth asteroids (NEAs) from the main
belt and in the dynamical spreading of asteroid families. At present, very
little is known about the thermal inertia of asteroids in the km size range.
Here we show that the average thermal inertia of a sample of NEAs in the
km-size range is 200 $\pm$ 40 J m−2 s−0.5 K−1. Furthermore,
we identify a trend of increasing thermal inertia with decreasing asteroid
diameter, D. This indicates that the dependence of the drift rate of the
orbital semimajor axis on the size of asteroids due to the Yarkovsky effect is
a more complex function than the generally adopted D^(−1) dependence, and
that the size distribution of objects injected by Yarkovsky-driven orbital
mobility into the NEA source regions is less skewed to smaller sizes than
generally assumed. We discuss how this fact may help to explain the small
difference in the slope of the size distribution of km-sized NEAs and main-belt
asteroids.


title:
Solutions of certain fractional kinetic equations and a fractional
  diffusion equation

abstract:
  In view of the usefulness and importance of the kinetic equation in certain
physical problems, the authors derive the explicit solution of a fractional
kinetic equation of general character, that unifies and extends earlier
results. Further, an alternative shorter method based on a result developed by
the authors is given to derive the solution of a fractional diffusion equation.


title: Strong enhancement of transport by interaction on contact links

abstract:
  Strong repulsive interactions within a one dimensional Fermi system in a
two-probe configuration normally lead to a reduced off-resonance conductance.
We show that if the repulsive interaction extends to the contact regions, a
strong increase of the conductance may occur, even for systems where one would
expect to find a reduced conductance. An essential ingredient in our
calculations is a momentum-space representation of the leads, which allows a
high energy resolution. Further, we demonstrate that these results are
independent of the high-energy cutoff and that the relevant scale is set by the
Fermi velocity.


title: Quantum Filtering of Optical Coherent States

abstract:
  We propose and experimentally demonstrate non-destructive and noiseless
removal (filtering) of vacuum states from an arbitrary set of coherent states
of continuous variable systems. Errors i.e. vacuum states in the quantum
information are diagnosed through a weak measurement, and on that basis,
probabilistically filtered out. We consider three different filters based on
on/off detection phase stabilized and phase randomized homodyne detection. We
find that on/off etection, optimal in the ideal theoretical setting, is
superior to the homodyne strategy in a practical setting.


title:
Interpreting and predicting the yield of transit surveys: Giant planets
  in the OGLE fields

abstract:
  Transiting extrasolar planets are now discovered jointly by photometric
surveys and by radial velocimetry. We want to determine whether the different
data sets are compatible between themselves and with models of the evolution of
extrasolar planets. We simulate directly a population of stars corresponding to
the OGLE transit survey and assign them planetary companions based on radial
velocimetry discoveries. We use a model of the evolution and structure of giant
planets assuming a variable fraction of heavy elements. The output list of
detectable planets of the simulations is compared to the real detections. We
confirm that the radial velocimetry and photometric survey data sets are
compatible within the statistical errors, assuming that planets with periods
between 1 and 2 days are approximately 5 times less frequent than planets with
periods between 2 and 5 days. We show that evolution models fitting present
observational constraints predict a lack of small giant planets with large
masses. We also identify distinct populations of planets: those with short
periods (P < 10d) are only found in orbit around metal-rich stars with [Fe/H] >
-0.07. We further confirm the relative absence of low-mass giant planets at
small orbital distances.


title:
Global Disk Oscillation Modes in Cataclysmic Variables and Other
  Newtonian Accretors

abstract:
  Diskoseismology, the theoretical study of small adiabatic hydrodynamical
global perturbations of geometrically thin, optically thick accretion disks
around black holes (and other compact objects), is a potentially powerful probe
of the gravitational field. For instance, the frequencies of the normal mode
oscillations can be used to determine the elusive angular momentum parameter of
the black hole. The general formalism developed by diskoseismologists for
relativistic systems can be readily applied to the Newtonian case of
cataclysmic variables (CVs). Some of these systems (e.g., the dwarf nova SS
Cygni) show rapid oscillations in the UV with periods of tens of seconds and
high coherence. In this paper, we assess the possibility that these dwarf nova
oscillations (DNOs) are diskoseismic modes. Besides its importance in
investigating the physical origin of DNOs, the present work could help us to
answer the following question. To what extent are the similarities in the
oscillation phenomenology of CVs and X-ray binaries (XRBs) indicative of a
common physical mechanism?


title:
Quantum molecular dynamics study of the pressure dependence of the
  ammonia inversion transition

abstract:
  The mechanism of the shift, broadening and quenching of the ammonia inversion
frequency with gas pressure has been a problem of lively interest for over
seventy years. A simple quantum model of the ammonia molecule perturbed by
collisions with ideal gas molecules displays the essential features of the
experimental data for NH3 and for ND3. The model does not display the behaviour
expected from theories of quantum localisation such as quantum state diffusion
and decoherence. On the other hand, models of perturbed classical oscillators
do display similar behaviour to our model. The quenching of the ammonia
inversion transition cannot therefore be interpreted as spatial localisation of
the wavefunction.


title: Relative Rigidity, Quasiconvexity and C-Complexes

abstract:
  We introduce and study the notion of relative rigidity for pairs $(X,\JJ)$
where 1) $X$ is a hyperbolic metric space and $\JJ$ a collection of quasiconvex
sets 2) $X$ is a relatively hyperbolic group and $\JJ$ the collection of
parabolics 3) $X$ is a higher rank symmetric space and $\JJ$ an equivariant
collection of maximal flats Relative rigidity can roughly be described as
upgrading a uniformly proper map between two such $\JJ$'s to a quasi-isometry
between the corresponding $X$'s.
  A related notion is that of a $C$-complex which is the adaptation of a Tits
complex to this context. We prove the relative rigidity of the collection of
pairs $(X, \JJ)$ as above. This generalises a result of Schwarz for symmetric
patterns of geodesics in hyperbolic space. We show that a uniformly proper map
induces an isomorphism of the corresponding $C$-complexes. We also give a
couple of characterizations of quasiconvexity. of subgroups of hyperbolic
groups on the way.


title:
Theory of enhanced second-harmonic generation by the quadrupole-dipole
  hybrid exciton

abstract:
  We report calculated substantial enhancement of the second harmonic
generation (SHG) in cuprous oxide crystals resonantly hybridized with an
appropriate organic material (DCM2:CA:PS 'solid-state solvent'). The quadrupole
origin of the inorganic part of the quadrupole-dipole hybrid provides inversion
symmetry breaking and the organic part contributes to the oscillator strength
of the hybrid. We show that the enhancement of the SHG, compared to bulk
cuprous oxide crystal, is proportional to the ratio of the DCM2 dipole moment
and the effective dipole moment of the quadrupole transitions in the cuprous
oxide. It is also inversely proportional to the line-width of the hybrid and
bulk excitons. The enhancement may be regulated by adjusting the organic blend
(mutual concentration of the DCM2 and CA part of the solvent) and pumping
conditions(varying the angle of incidence in case of optical pumping or
populating the minimum of the lower branch of the hybrid in case of electrical
pumping).


title:
Error Estimation and Atomistic-Continuum Adaptivity for the
  Quasicontinuum Approximation of a Frenkel-Kontorova Model

abstract:
  We propose and analyze a goal-oriented a posteriori error estimator for the
atomistic-continuum modeling error in the quasicontinuum method. Based on this
error estimator, we develop an algorithm which adaptively determines the
atomistic and continuum regions to compute a quantity of interest to within a
given tolerance. We apply the algorithm to the computation of the structure of
a crystallographic defect described by a Frenkel-Kontorova model and present
the results of numerical experiments. The numerical results show that our
method gives an efficient estimate of the error and a nearly optimal
atomistic-continuum modeling strategy.


title:
Blind Identification of Distributed Antenna Systems with Multiple
  Carrier Frequency Offsets

abstract:
  In spatially distributed multiuser antenna systems, the received signal
contains multiple carrier-frequency offsets (CFOs) arising from mismatch
between the oscillators of transmitters and receivers. This results in a
time-varying rotation of the data constellation, which needs to be compensated
at the receiver before symbol recovery. In this paper, a new approach for blind
CFO estimation and symbol recovery is proposed. The received base-band signal
is over-sampled, and its polyphase components are used to formulate a virtual
Multiple-Input Multiple-Output (MIMO) problem. By applying blind MIMO system
estimation techniques, the system response can be estimated and decoupled
versions of the user symbols can be recovered, each one of which contains a
distinct CFO. By applying a decision feedback Phase Lock Loop (PLL), the CFO
can be mitigated and the transmitted symbols can be recovered. The estimated
MIMO system response provides information about the CFOs that can be used to
initialize the PLL, speed up its convergence, and avoid ambiguities usually
linked with PLL.


title:
The Distribution of the first Eigenvalue Spacing at the Hard Edge of the
  Laguerre Unitary Ensemble

abstract:
  The distribution function for the first eigenvalue spacing in the Laguerre
unitary ensemble of finite rank random matrices is found in terms of a
Painlev\'e V system, and the solution of its associated linear isomonodromic
system. In particular it is characterised by the polynomial solutions to the
isomonodromic equations which are also orthogonal with respect to a deformation
of the Laguerre weight. In the scaling to the hard edge regime we find an
analogous situation where a certain Painlev\'e \IIId system and its associated
linear isomonodromic system characterise the scaled distribution. We undertake
extensive analytical studies of this system and use this knowledge to
accurately compute the distribution and its moments for various values of the
parameter $ a $. In particular choosing $ a=\pm 1/2 $ allows the first
eigenvalue spacing distribution for random real orthogonal matrices to be
computed.


title:
Second-order perturbations of cosmological fluids: Relativistic effects
  of pressure, multi-component, curvature, and rotation

abstract:
  We present general relativistic correction terms appearing in Newton's
gravity to the second-order perturbations of cosmological fluids. In our
previous work we have shown that to the second-order perturbations, the density
and velocity perturbation equations of general relativistic zero-pressure,
irrotational, single-component fluid in a flat background coincide exactly with
the ones known in Newton's theory. Here, we present the general relativistic
second-order correction terms arising due to (i) pressure, (ii)
multi-component, (iii) background curvature, and (iv) rotation. In case of
multi-component zero-pressure, irrotational fluids under the flat background,
we effectively do not have relativistic correction terms, thus the relativistic
result again coincides with the Newtonian ones. In the other three cases we
generally have pure general relativistic correction terms. In case of pressure,
the relativistic corrections appear even in the level of background and linear
perturbation equations. In the presence of background curvature, or rotation,
pure relativistic correction terms directly appear in the Newtonian equations
of motion of density and velocity perturbations to the second order. In the
small-scale limit (far inside the horizon), relativistic equations including
the rotation coincide with the ones in Newton's gravity.


title: Highly turbulent solutions of LANS-alpha and their LES potential

abstract:
  We compute solutions of the Lagrangian-Averaged Navier-Stokes alpha-model
(LANS) for significantly higher Reynolds numbers (up to Re 8300) than have
previously been accomplished. This allows sufficient separation of scales to
observe a Navier-Stokes (NS) inertial range followed by a 2nd LANS inertial
range. The analysis of the third-order structure function scaling supports the
predicted l^3 scaling; it corresponds to a k^(-1) scaling of the energy
spectrum. The energy spectrum itself shows a different scaling which goes as
k^1. This latter spectrum is consistent with the absence of stretching in the
sub-filter scales due to the Taylor frozen-in hypothesis employed as a closure
in the derivation of LANS. These two scalings are conjectured to coexist in
different spatial portions of the flow. The l^3 (E(k) k^(-1)) scaling is
subdominant to k^1 in the energy spectrum, but the l^3 scaling is responsible
for the direct energy cascade, as no cascade can result from motions with no
internal degrees of freedom. We verify the prediction for the size of the LANS
attractor resulting from this scaling. From this, we give a methodology either
for arriving at grid-independent solutions for LANS, or for obtaining a
formulation of a LES optimal in the context of the alpha models. The fully
converged grid-independent LANS may not be the best approximation to a direct
numerical simulation of the NS equations since the minimum error is a balance
between truncation errors and the approximation error due to using LANS instead
of the primitive equations. Furthermore, the small-scale behavior of LANS
contributes to a reduction of flux at constant energy, leading to a shallower
energy spectrum for large alpha. These small-scale features, do not preclude
LANS to reproduce correctly the intermittency properties of high Re flow.


title: Reentrant Orbital Order and the True Ground State of LaSr2Mn2O7

abstract:
  Contrary to conventional wisdom, our purified La2-2xSr1+2xMn2O7 crystals
exhibit CE-type orbital and charge order as the low-temperature ground state
for a hole doping level h = 0.5. For small deviations from h = 0.5, the high
temperature CE phase is replaced at low temperatures by an A-type
antiferromagnet without coexistence. Larger deviations result in a lack of CE
order at any temperature. Thus, small inhomogeneities in cation or oxygen
composition could explain why others commonly see this reentrance with
coexistence.


title:
Addendum: A Classification of Plane Symmetric Kinematic Self-similar
  Solutions

abstract:
  In our recent paper, we classified plane symmetric kinematic self-similar
perfect fluid and dust solutions of the second, zeroth and infinite kinds.
However, we have missed some solutions during the process. In this short
communication, we add up those missing solutions. We have found a total of
seven solutions, out of which five turn out to be independent and cannot be
found in the earlier paper


title: Weak non-linearities and cluster states

abstract:
  We propose a scalable approach to building cluster states of matter qubits
using coherent states of light. Recent work on the subject relies on the use of
single photonic qubits in the measurement process. These schemes have a low
initial success probability and low detector efficiencies cause a serious
blowup in resources. In contrast, our approach uses continuous variables and
highly efficient measurements. We present a two-qubit scheme, with a simple
homodyne measurement system yielding an entangling operation with success
probability 1/2. Then we extend this to a three-qubit interaction, increasing
this probability to 3/4. We discuss the important issues of the overhead cost
and the time scaling, showing how these can be vastly improved with access to
this new probability range.


title: A discriminating probe of gravity at cosmological scales

abstract:
  The standard cosmological model is based on general relativity and includes
dark matter and dark energy. An important prediction of this model is a fixed
relationship between the gravitational potentials responsible for gravitational
lensing and the matter overdensity. Alternative theories of gravity often make
different predictions for this relationship. We propose a set of measurements
which can test the lensing/matter relationship, thereby distinguishing between
dark energy/matter models and models in which gravity differs from general
relativity. Planned optical, infrared and radio galaxy and lensing surveys will
be able to measure $E_G$, an observational quantity whose expectation value is
equal to the ratio of the Laplacian of the Newtonian potentials to the peculiar
velocity divergence, to percent accuracy. We show that this will easily
separate alternatives such as $\Lambda$CDM, DGP, TeVeS and $f(R)$ gravity.


title:
The Loewner driving function of trajectory arcs of quadratic
  differentials

abstract:
  We obtain a first order differential equation for the driving function of the
chordal Loewner differential equation in the case where the domain is slit by a
curve which is a trajectory arc of certain quadratic differentials. In
particular this includes the case when the curve is a path on the square,
triangle or hexagonal lattice in the upper halfplane or, indeed, in any domain
with boundary on the lattice. We also demonstrate how we use this to calculate
the driving function numerically. Equivalent results for other variants of the
Loewner differential equation are also obtained: Multiple slits in the chordal
Loewner differential equation and the radial Loewner differential equation. The
method also works for other versions of the Loewner differential equation. The
proof of our formula uses a generalization of Schwarz-Christoffel mapping to
domains bounded by trajectory arcs of rotations of a given quadratic
differential that is of interest in its own right.


title: On the measurement problem for a two-level quantum system

abstract:
  A geometric approach to quantum mechanics with unitary evolution and
non-unitary collapse processes is developed. In this approach the Schrodinger
evolution of a quantum system is a geodesic motion on the space of states of
the system furnished with an appropriate Riemannian metric. The measuring
device is modeled by a perturbation of the metric. The process of measurement
is identified with a geodesic motion of state of the system in the perturbed
metric. Under the assumption of random fluctuations of the perturbed metric,
the Born rule for probabilities of collapse is derived. The approach is applied
to a two-level quantum system to obtain a simple geometric interpretation of
quantum commutators, the uncertainty principle and Planck's constant. In light
of this, a lucid analysis of the double-slit experiment with collapse and an
experiment on a pair of entangled particles is presented.


title: Global-String and Vortex Superfluids in a Supersymmetric Scenario

abstract:
  The main goal of this work is to investigate the possibility of finding the
supersymmetric version of the U(1)-global string model which behaves as a
vortex-superfluid. To describe the superfluid phase, we introduce a
Lorentz-symmetry breaking background that, in an approach based on
supersymmetry, leads to a discussion on the relation between the violation of
Lorentz symmetry and explicit soft supersymmetry breakings. We also study the
relation between the string configuration and the vortex-superfluid phase. In
the framework we settle down in terms of superspace and superfields, we
actually establish a duality between the vortex degrees of freedom and the
component fields of the Kalb-Ramond superfield. We make also considerations
about the fermionic excitations that may appear in connection with the vortex
formation.


title:
Identities for number series and their reciprocals: Dirac delta function
  approach

abstract:
  Dirac delta function (delta-distribution) approach can be used as efficient
method to derive identities for number series and their reciprocals. Applying
this method, a simple proof for identity relating prime counting function
(pi-function) and logarithmic integral (Li-function) can be obtained.


title: Light quark masses from unquenched lattice QCD

abstract:
  We calculate the light meson spectrum and the light quark masses by lattice
QCD simulation, treating all light quarks dynamically and employing the Iwasaki
gluon action and the nonperturbatively O(a)-improved Wilson quark action. The
calculations are made at the squared lattice spacings at an equal distance
a^2~0.005, 0.01 and 0.015 fm^2, and the continuum limit is taken assuming an
O(a^2) discretization error. The light meson spectrum is consistent with
experiment. The up, down and strange quark masses in the \bar{MS} scheme at 2
GeV are \bar{m}=(m_{u}+m_{d})/2=3.55^{+0.65}_{-0.28} MeV and
m_s=90.1^{+17.2}_{-6.1} MeV where the error includes statistical and all
systematic errors added in quadrature. These values contain the previous
estimates obtained with the dynamical u and d quarks within the error.


title:
The Chow ring of the moduli space and its related homogeneous space of
  bundles on P^2 with charge 1

abstract:
  For an algebraically closed field K with ch K \not = 2, we determine the Chow
ring of the moduli space of holomorphic bundles on a projective plane with the
structure group SO(n,K) and half the first Pontryagin index being equal to 1,
each of which is trivial on a fixed line and has a fixed holomorphic
trivialization there.


title:
Entanglement condition via su(2) and su(1,1) algebra using
  Schr{\"o}dinger-Robertson uncertainty relation

abstract:
  The Schr{\"o}dinger-Robertson inequality generally provides a stronger bound
on the product of uncertainties for two noncommuting observables than the
Heisenberg uncertainty relation, and as such, it can yield a stricter
separability condition in conjunction with partial transposition. In this
paper, using the Schr{\"o}dinger-Robertson uncertainty relation, the
separability condition previously derived from the su(2) and the su(1,1)
algebra is made stricter and refined to a form invariant with respect to local
phase shifts. Furthermore, a linear optical scheme is proposed to test this
invariant separability condition.


title:
Additional Explanatory Notes on the Analytic Proof of the Finite
  Generation of the Canonical Ring

abstract:
  This set of notes provides some additional explanatory material on the
analytic proof of the finite generation of the canonical ring for a compact
complex algebraic manifold of general type.


title: Tait's conjectures and odd crossing number amphicheiral knots

abstract:
  We give a brief historical overview of the Tait conjectures, made 120 years
ago in the course of his pioneering work in tabulating the simplest knots, and
solved a century later using the Jones polynomial. We announce the solution,
again based on a substantial study of the Jones polynomial, of one (possibly
his last remaining?) problem of Tait, with the construction of amphicheiral
knots of almost all odd crossing numbers. An application to the non-triviality
problem for the Jones polynomial is also outlined.


title:
A revisit of the papers on the theory of relativity: Reconsideration of
  the hypothesis of ether-dragging

abstract:
  This paper revisits previous papers related to the theory of relativity.
Afterwards, a reconsideration of the hypothesis of ether-dragging is discussed.
The ether is compatible with the theory of relativity and historical
experiments; this paper explains the Michelson-Morley experiment using the
ether-dragging hypothesis without the orthodox interpretation that the speed c
is a fixed constant in terms of any system of inertial coordinates.


title:
The ideal-valued index for a dihedral group action, and mass partition
  by two hyperplanes

abstract:
  We compute the complete Fadell-Husseini index of the 8 element dihedral group
D_8 acting on S^d \times S^d, both for F_2 and for integer coefficients. This
establishes the complete goup cohomology lower bounds for the two hyperplane
case of Gr"unbaum's 1960 mass partition problem: For which d and j can any j
arbitrary measures be cut into four equal parts each by two suitably-chosen
hyperplanes in R^d? In both cases, we find that the ideal bounds are not
stronger than previously established bounds based on one of the maximal abelian
subgroups of D_8.


title:
A new method of alpha ray measurement using a Quadrupole Mass
  Spectrometer

abstract:
  We propose a new method of alpha($\alpha$)-ray measurement that detects
helium atoms with a Quadrupole Mass Spectrometer(QMS). A demonstration is
undertaken with a plastic-covered $^{241}$Am $\alpha$-emitting source to detect
$\alpha$-rays stopped in the capsule. We successfully detect helium atoms that
diffuse out of the capsule by accumulating them for one to 20 hours in a closed
chamber. The detected amount is found to be proportional to the accumulation
time. Our method is applicable to probe $\alpha$-emitting radioactivity in bulk
material.


title: Magnetorotational Collapse of Population III Stars

abstract:
  We perform a series of two-dimensional magnetorotational core-collapse
simulations of Pop III stars. Changing the initial distributions of rotation
and magnetic fields prior to collapse in a parametric manner, we compute 19
models. By so doing, we systematically investigate how rotation and magnetic
fields affect the collapse dynamics and explore how the properties of the
black-hole formations and neutrino emissions could be affected. As for the
microphysics, we employ a realistic equation of state and approximate the
neutrino transfer by a multiflavour leakage scheme. With these computations, we
find that the jet-like explosions are obtained by the magnetodriven shock waves
if the initial magnetic field is as large as $10^{12}$ G. We point out that the
black-hole masses at the formation decrease with the initial field strength, on
the other hand, increase with the initial rotation rates. As for the neutrino
properties, we point out that the degree of the differential rotation plays an
important role to determine which species of the neutrino luminosity is more
dominant than the others. Furthermore, we find that the stronger magnetic
fields make the peak neutrino luminosities smaller, because the magnetic
pressure acts to halt the collapse in the central regions, leading to the
suppression of the releasable gravitational binding energies.


title: Hyperfine Quenching of the $4s4p ^{3}P_{0}$ Level in Zn-like Ions

abstract:
  In this paper, we used the multiconfiguration Dirac-Fock method to compute
with high precision the influence of the hyperfine interaction on the
$[Ar]3d^{10} 4s4p ^3P_0$ level lifetime in Zn-like ions for stable and some
quasi-stable isotopes of nonzero nuclear spin between Z=30 and Z=92. The
influence of this interaction on the $[Ar]3d^{10} 4s4p ^3P_1 - [Ar]3d^{10} 4s4p
^3P_0$ separation energy is also calculated for the same ions.


title: R-matrices in Rime

abstract:
  We replace the ice Ansatz on matrix solutions of the Yang-Baxter equation by
a weaker condition which we call "rime". Rime solutions include the standard
Drinfeld-Jimbo R-matrix. Solutions of the Yang--Baxter equation within the rime
Ansatz which are maximally different from the standard one we call "strict
rime". A strict rime non-unitary solution is parameterized by a projective
vector. We show that this solution transforms to the Cremmer-Gervais R-matrix
by a change of basis with a matrix containing symmetric functions in the
components of the parameterizing vector. A strict unitary solution (the rime
Ansatz is well adapted for taking a unitary limit) is shown to be equivalent to
a quantization of a classical "boundary" r-matrix of Gerstenhaber and
Giaquinto. We analyze the structure of the elementary rime blocks and find, as
a by-product, that all non-standard R-matrices of GL(1|1)-type can be uniformly
described in a rime form.
  We discuss then connections of the classical rime solutions with the Bezout
operators. The Bezout operators satisfy the (non-)homogeneous associative
classical Yang--Baxter equation which is related to the Rota-Baxter operators.
  We classify the rime Poisson brackets: they form a 3-dimensional pencil. A
normal form of each individual member of the pencil depends on the discriminant
of a certain quadratic polynomial. We also classify orderable quadratic rime
associative algebras.
  For the standard Drinfeld-Jimbo solution, there is a choice of the
multiparameters, for which it can be non-trivially rimed. However, not every
Belavin-Drinfeld triple admits a choice of the multiparameters for which it can
be rimed. We give a minimal example.


title: Quadratic centers defining elliptic surfaces

abstract:
  Let $X$ be a quadratic vector field with a center whose generic orbits are
algebraic curves of genus one. To each $X$ we associate an elliptic surface (a
smooth complex compact surface which is a genus one fibration). We give the
list of all such vector fields and determine the corresponding elliptic
surfaces.


title:
Corner Transfer Matrix Renormalization Group Method Applied to the Ising
  Model on the Hyperbolic Plane

abstract:
  Critical behavior of the Ising model is investigated at the center of large
scale finite size systems, where the lattice is represented as the tiling of
pentagons. The system is on the hyperbolic plane, and the recursive structure
of the lattice makes it possible to apply the corner transfer matrix
renormalization group method. From the calculated nearest neighbor spin
correlation function and the spontaneous magnetization, it is concluded that
the phase transition of this model is mean-field like. One parameter
deformation of the corner Hamiltonian on the hyperbolic plane is discussed.


title: Inferring periodic orbits from spectra of simple shaped micro-lasers

abstract:
  Dielectric micro-cavities are widely used as laser resonators and
characterizations of their spectra are of interest for various applications. We
experimentally investigate micro-lasers of simple shapes (Fabry-Perot, square,
pentagon, and disk). Their lasing spectra consist mainly of almost equidistant
peaks and the distance between peaks reveals the length of a quantized periodic
orbit. To measure this length with a good precision, it is necessary to take
into account different sources of refractive index dispersion. Our experimental
and numerical results agree with the superscar model describing the formation
of long-lived states in polygonal cavities. The limitations of the
two-dimensional approximation are briefly discussed in connection with
micro-disks.


title:
Zeta function and cryptographic exponent of supersingular curves of
  genus 2

abstract:
  We compute in a direct (not algorithmic) way the zeta function of all
supersingular curves of genus 2 over a finite field k, with many geometric
automorphisms. We display these computations in an appendix where we select a
family of representatives of all these curves up to geometric isomorphism and
we exhibit equations and the zeta function of all their twists. As an
application we obtain a direct computation of the cryptographic exponent of the
Jacobians of these curves.


title: Dynamic Effects Increasing Network Vulnerability to Cascading Failures

abstract:
  We study cascading failures in networks using a dynamical flow model based on
simple conservation and distribution laws to investigate the impact of
transient dynamics caused by the rebalancing of loads after an initial network
failure (triggering event). It is found that considering the flow dynamics may
imply reduced network robustness compared to previous static overload failure
models. This is due to the transient oscillations or overshooting in the loads,
when the flow dynamics adjusts to the new (remaining) network structure. We
obtain {\em upper} and {\em lower} limits to network robustness, and it is
shown that {\it two} time scales $\tau$ and $\tau_0$, defined by the network
dynamics, are important to consider prior to accurately addressing network
robustness or vulnerability. The robustness of networks showing cascading
failures is generally determined by a complex interplay between the network
topology and flow dynamics, where the ratio $\chi=\tau/\tau_0$ determines the
relative role of the two of them.


title:
Ramsey fringes formation during excitation of topological modes in a
  Bose-Einstein condensate

abstract:
  The Ramsey fringes formation during the excitation of topological coherent
modes of a Bose-Einstein condensate by an external modulating field is
considered. The Ramsey fringes appear when a series of pulses of the excitation
field is applied. In both Rabi and Ramsey interrogations, there is a shift of
the population maximum transfer due to the strong non-linearity present in the
system. It is found that the Ramsey pattern itself retains information about
the accumulated relative phase between both ground and excited coherent modes.


title: The Allen-Cahn Action functional in higher dimensions

abstract:
  The Allen-Cahn action functional is related to the probability of rare events
in the stochastically perturbed Allen-Cahn equation. Formal calculations
suggest a reduced action functional in the sharp interface limit. We prove in
two and three space dimensions the corresponding lower bound. One difficulty is
that diffuse interfaces may collapse in the limit. We therefore consider the
limit of diffuse surface area measures and introduce a generalized velocity and
generalized reduced action functional in a class of evolving measures. As a
corollary we obtain the Gamma convergence of the action functional in a class
of regularly evolving hypersurfaces.


title:
Metrical characterization of super-reflexivity and linear type of Banach
  spaces

abstract:
  We prove that a Banach space X is not super-reflexive if and only if the
hyperbolic infinite tree embeds metrically into X. We improve one implication
of J.Bourgain's result who gave a metrical characterization of
super-reflexivity in Banach spaces in terms of uniforms embeddings of the
finite trees. A characterization of the linear type for Banach spaces is given
using the embedding of the infinite tree equipped with a suitable metric.


title:
Search for exclusive events using the dijet mass fraction at the
  Tevatron

abstract:
  In this paper, we discuss the observation of exclusive events using the dijet
mass fraction as measured by the CDF collaboration at the Tevatron. We compare
the data to pomeron exchange inspired models as well as Soft color interaction
ones. We also provide the prediction on dijet mass fraction at the LHC using
both exclusive and inclusive diffractive events.


title: Entanglement Cost for Sequences of Arbitrary Quantum States

abstract:
  The entanglement cost of arbitrary sequences of bipartite states is shown to
be expressible as the minimization of a conditional spectral entropy rate over
sequences of separable extensions of the states in the sequence. The expression
is shown to reduce to the regularized entanglement of formation when the n-th
state in the sequence consists of n copies of a single bipartite state.


title:
Line and continuum variability of two intermediate-redshift,
  high-luminosity quasars

abstract:
  It has been shown that the luminosity of AGNs and the size of their broad
line region obey a simple relation of the type R=a L^g, from faint Seyfert
nuclei to bright quasars, allowing single-epoch determination of the central
black hole mass M=b L^g D^2 from their luminosity L and width of H_beta
emission line. Adopting this mass determination for cosmological studies
requires the extrapolation to high z and L of a relation whose calibration
relies so far on reverberation mapping measurements performed for L<10^46 erg/s
and z<0.4. We initiated a campaign for the monitoring of a few luminous,
intermediate z quasars whose apparent magnitude V<15.7 allows observations with
a 1.8m telescope, aimed at proving that emission lines vary and respond to
continuum variations even for luminosities >10^47 erg/s, and determining
eventually their M_BH from reverberation mapping. We have repeatedly performed
simultaneous observations of quasars and reference stars to determine relative
variability of continuum and emission lines. We describe the observations and
methods of analysis. For the quasars PG1634+706 and PG1247+268 we obtain
light-curves respectively for CIII], MgII and for CIV, CIII] emission lines
with the relevant continua. During 3.2 years of observation, in the former case
no continuum variability has been detected and the evidence for line
variability is marginal, while in the latter case both continuum and line
variability are detected with high significance and the line variations appear
correlated with continuum variations. The detection of the emission line
variability in a quasar with L~10^47 erg/s encourages the prosecution of the
campaign which should provide a black hole mass estimate in other 5-6 years,
constraining the M_BH-L relation in a poorly explored range of luminosity.


title:
Adiabatic passage in a three-state system with non-Markovian relaxation:
  The role of excited-state absorption and two-exciton processes

abstract:
  The influence of excited-state absorption (ESA) and two-exciton processes on
a coherent population transfer with intense ultrashort chirped pulses in
molecular systems in solution has been studied. An unified treatment of
adiabatic rapid passage (ARP) in such systems has been developed using a
three-state electronic system with relaxation treated as a diffusion on
electronic potential energy surfaces. We have shown that ESA has a profound
effect on coherent population transfer in large molecules that necessitates a
more accurate interpretation of experimental data. A simple and physically
clear model for ARP in molecules with three electronic states in solution has
been developed by extending the Landau-Zener calculations putting in a third
level to random crossing of levels. A method for quantum control of two-exciton
states in molecular complexes has been proposed.


title:
Harmonic bilocal fields generated by globally conformal invariant scalar
  fields

abstract:
  The twist two contribution in the operator product expansion of phi_1(x_1)
phi_2(x_2) for a pair of globally conformal invariant, scalar fields of equal
scaling dimension d in four space-time dimensions is a field V_1(x_1,x_2) which
is harmonic in both variables. It is demonstrated that the Huygens bilocality
of V_1 can be equivalently characterized by a "single-pole property" concerning
the pole structure of the (rational) correlation functions involving the
product phi_1(x_1) phi_2(x_2). This property is established for the dimension
d=2 of phi_1, phi_2. As an application we prove that any system of GCI scalar
fields of conformal dimension 2 (in four space-time dimensions) can be
presented as a (possibly infinite) superposition of products of free massless
fields.


title:
Impact of spin-zero particle-photon interactions on light polarization
  in external magnetic fields

abstract:
  If the recent PVLAS results on polarization changes of a linearly polarized
laser beam passing through a magnetic field are interpreted by an axion-like
particle, it is almost certain that it is not a standard QCD axion. Considering
this, we study the general effective interactions of photons with spin-zero
particles without restricting the latter to be a pseudo-scalar or a scalar,
i.e., a parity eigenstate. At the lowest order in effective field theory, there
are two dimension-5 interactions, each of which has previously been treated
separately for a pseudo-scalar or a scalar particle. By following the evolution
in an external magnetic field of the system of spin-zero particles and photons,
we compute the changes in light polarization and the transition probability for
two experimental set-ups: one-way propagation and round-trip propagation. While
the first may be relevant for astrophysical sources of spin-zero particles, the
second applies to laboratory optical experiments like PVLAS. In the one-way
propagation, interesting phenomena can occur for special configurations of
polarization where, for instance, transition occurs but light polarization does
not change. For the round-trip propagation, however, the standard results of
polarization changes for a pseudoscalar or a scalar are only modified by a
factor that depends on the relative strength of the two interactions.


title: A simple test of quantumness for a single system

abstract:
  We propose a simple test of quantumness which can decide whether for the
given set of accessible experimental data the classical model is insufficient.
Take two observables $ A,B$ such that for any state $\psi$ their mean values
satisfy $0\leq <\psi|A|\psi>\leq <\psi|B|\psi>\leq 1$. If there exists a state
$\phi$ such that the second moments fulfill the inequality $<\phi|A^2|\phi>
><\phi|B^2|\phi>$ then the system cannot be described by the classical
probabilistic scheme. An example of an optimal triple $(A,B,\phi)$ in the case
of a qubit is given.


title:
SPITZER: Accretion in Low Mass Stars and Brown Dwarfs in the Lambda
  Orionis Cluster

abstract:
  We present multi-wavelength optical and infrared photometry of 170 previously
known low mass stars and brown dwarfs of the 5 Myr Collinder 69 cluster (Lambda
Orionis). The new photometry supports cluster membership for most of them, with
less than 15% of the previous candidates identified as probable non-members.
The near infrared photometry allows us to identify stars with IR excesses, and
we find that the Class II population is very large, around 25% for stars (in
the spectral range M0 - M6.5) and 40% for brown dwarfs, down to 0.04 Msun,
despite the fact that the H(alpha) equivalent width is low for a significant
fraction of them. In addition, there are a number of substellar objects,
classified as Class III, that have optically thin disks. The Class II members
are distributed in an inhomogeneous way, lying preferentially in a filament
running toward the south-east. The IR excesses for the Collinder 69 members
range from pure Class II (flat or nearly flat spectra longward of 1 micron), to
transition disks with no near-IR excess but excesses beginning within the IRAC
wavelength range, to two stars with excess only detected at 24 micron.
Collinder 69 thus appears to be at an age where it provides a natural
laboratory for the study of primordial disks and their dissipation.


title:
A data-analysis driven comparison of analytic and numerical coalescing
  binary waveforms: nonspinning case

abstract:
  We compare waveforms obtained by numerically evolving nonspinning binary
black holes to post-Newtonian (PN) template families currently used in the
search for gravitational waves by ground-based detectors. We find that the
time-domain 3.5PN template family, which includes the inspiral phase, has
fitting factors (FFs) >= 0.96 for binary systems with total mass M = 10 ~ 20
Msun. The time-domain 3.5PN effective-one-body template family, which includes
the inspiral, merger and ring-down phases, gives satisfactory signal-matching
performance with FFs >= 0.96 for binary systems with total mass M = 10 ~ 120
Msun. If we introduce a cutoff frequency properly adjusted to the final
black-hole ring-down frequency, we find that the frequency-domain
stationary-phase-approximated template family at 3.5PN order has FFs >= 0.96
for binary systems with total mass M = 10 ~ 20 Msun. However, to obtain high
matching performances for larger binary masses, we need to either extend this
family to unphysical regions of the parameter space or introduce a 4PN order
coefficient in the frequency-domain GW phase. Finally, we find that the
phenomenological Buonanno-Chen-Vallisneri family has FFs >= 0.97 with total
mass M=10 ~ 120Msun. The main analyses use the noise spectral-density of LIGO,
but several tests are extended to VIRGO and advanced LIGO noise-spectral
densities.


title:
Quantum entanglement of decohered two-mode squeezed states in absorbing
  and amplifying environment

abstract:
  We investigate the properties of quantum entanglement of two-mode squeezed
states interacting with linear baths with general gain and loss parameters. By
explicitly solving for \rho from the master equation, we determine analytical
expressions of eigenvalues and eigenvectors of \rho^{T_A} (the partial
transposition of density matrix \rho). In Fock space, \rho^{T_A} is shown to
maintain a block diagonal structure as the system evolves. In addition, we
discover that the decoherence induced by the baths would break the degeneracy
of \rho^{T_A}, and leads to a novel set of eigenvectors for the construction of
entanglement witness operators. Such eigenvectors are shown to be
time-independent, which is a signature of robust entanglement of two-mode
squeezed states in the presence of noise.


title: Some new observations on interpolation in the spectral unit ball

abstract:
  We present several results associated to a holomorphic-interpolation problem
for the spectral unit ball \Omega_n, n\geq 2. We begin by showing that a known
necessary condition for the existence of a
$\mathcal{O}(D;\Omega_n)$-interpolant (D here being the unit disc in the
complex plane), given that the matricial data are non-derogatory, is not
sufficient. We provide next a new necessary condition for the solvability of
the two-point interpolation problem -- one which is not restricted only to
non-derogatory data, and which incorporates the Jordan structure of the
prescribed data. We then use some of the ideas used in deducing the latter
result to prove a Schwarz-type lemma for holomorphic self-maps of \Omega_n,
n\geq 2.


title: The microcanonical ensemble of the ideal relativistic quantum gas

abstract:
  We derive the microcanonical partition function of the ideal relativistic
quantum gas of spinless bosons in a quantum field framework as an expansion
over fixed multiplicities. Our calculation generalizes well known expressions
in literature in that it does not introduce any large volume approximation and
it is valid at any volume. We discuss the issues concerned with the definition
of the microcanonical ensemble for a free quantum field at volumes comparable
with the Compton wavelength and provide a consistent prescription of
calculating the microcanonical partition function, which is finite at finite
volume and yielding the correct thermodynamic limit. Besides an immaterial
overall factor, the obtained expression turns out to be the same as in the
non-relativistic multi-particle approach. This work is introductory to derive
the most general expression of the microcanonical partition function fixing the
maximal set of observables of the Poincare' group.


title: The spin-flip phenomenon in supermassive black hole binary mergers

abstract:
  Massive merging black holes will be the primary sources of powerful
gravitational waves at low frequency, and will permit to test general
relativity with candidate galaxies close to a binary black hole merger. In this
paper we identify the typical mass ratio of the two black holes but then show
that the distance when gravitational radiation becomes the dominant dissipative
effect (over dynamical friction) does not depend on the mass ratio. However the
dynamical evolution in the gravitational wave emission regime does. For the
typical range of mass ratios the final stage of the merger is preceded by a
rapid precession and a subsequent spin-flip of the main black hole. This
already occurs in the inspiral phase, therefore can be described analytically
by post-Newtonian techniques. We then identify the radio galaxies with a
super-disk as those in which the rapidly precessing jet produces effectively a
powerful wind, entraining the environmental gas to produce the appearance of a
thick disk. These specific galaxies are thus candidates for a merger of two
black holes to happen in the astronomically near future.


title: On the Young-Fibonacci insertion algorithm

abstract:
  This work is concerned with some properties of the Young-Fibonacci insertion
algorithm and its relation with Fomin's growth diagrams. It also investigates a
relation between the combinatorics of Young-Fibonacci tableaux and the study of
Okada's algebra associated to the Young-Fibonacci lattice. The original
algorithm was introduced by Roby and we redefine it in such a way that both the
insertion and recording tableaux of any permutation are \emph{conveniently}
interpreted as chains in the Young-Fibonacci lattice. A property of
Killpatrick's evacuation is given a simpler proof, but this evacuation is no
longer needed in making Roby's and Fomin's constructions coincide. We provide
the set of Young-Fibonacci tableaux of size $n$ with a structure of graded
poset, induced by the weak order on permutations of the symmetric group, and
realized by transitive closure of elementary transformations on tableaux. We
show that this poset gives a combinatorial interpretation of the coefficients
in the transition matrix from the analogue of complete symmetric functions to
analogue of the Schur functions in Okada's algebra. We end with a quite similar
observation for four posets on Young-tableaux studied by Taskin.


title:
Thermoelectric response near a quantum critical point: the case of
  CeCoIn5

abstract:
  We present a study of thermoelectric coefficients in CeCoIn_5 down to 0.1 K
and up to 16 T in order to probe the thermoelectric signatures of quantum
criticality. In the vicinity of the field-induced quantum critical point, the
Nernst coefficient nu exhibits a dramatic enhancement without saturation down
to lowest measured temperature. The dimensionless ratio of Seebeck coefficient
to electronic specific heat shows a minimum at a temperature close to threshold
of the quasiparticle formation. Close to T_c(H), in the vortex-liquid state,
the Nernst coefficient behaves anomalously in puzzling contrast with other
superconductors and standard vortex dynamics.


title: Dissipative dynamics of superfluid vortices at non-zero temperatures

abstract:
  We consider the evolution and dissipation of vortex rings in a condensate at
non-zero temperature, in the context of the classical field approximation,
based on the defocusing nonlinear Schr\"odinger equation. The temperature in
such a system is fully determined by the total number density and the number
density of the condensate. A vortex ring is introduced into a condensate in a
state of thermal equilibrium, and interacts with non-condensed particles. These
interactions lead to a gradual decrease in the vortex line density, until the
vortex ring completely disappears. We show that the square of the vortex line
length changes linearly with time, and obtain the corresponding universal decay
law. We relate this to mutual friction coefficients in the fundamental equation
of vortex motion in superfluids.


title:
Critical edge behavior in unitary random matrix ensembles and the thirty
  fourth Painleve transcendent

abstract:
  We describe a new universality class for unitary invariant random matrix
ensembles. It arises in the double scaling limit of ensembles of random $n
\times n$ Hermitian matrices $Z_{n,N}^{-1} |\det M|^{2\alpha} e^{-N \Tr V(M)}
dM$ with $\alpha > -1/2$, where the factor $|\det M|^{2\alpha}$ induces
critical eigenvalue behavior near the origin. Under the assumption that the
limiting mean eigenvalue density associated with $V$ is regular, and that the
origin is a right endpoint of its support, we compute the limiting eigenvalue
correlation kernel in the double scaling limit as $n, N \to \infty$ such that
$n^{2/3}(n/N-1) = O(1)$. We use the Deift-Zhou steepest descent method for the
Riemann-Hilbert problem for polynomials on the line orthogonal with respect to
the weight $|x|^{2\alpha} e^{-NV(x)}$. Our main attention is on the
construction of a local parametrix near the origin by means of the
$\psi$-functions associated with a distinguished solution of the Painleve XXXIV
equation. This solution is related to a particular solution of the Painleve II
equation, which however is different from the usual Hastings-McLeod solution.


title:
Vibrational effects on low-temperature properties of molecular
  conductors

abstract:
  We calculate characteristic correlation functions for the Anderson model with
additional phonon-assisted coupling to the odd conduction channel. This model
describes, for example, the behavior of a molecule embedded between two
electrodes in linear transport experiments where the position of the molecule
with respect to the leads affects the tunneling amplitudes. We use variational
projection-operator method and numerical renormalization group (NRG) method.
The spin is Kondo screened either by even or odd conduction channel depending
on the gate voltage and electron-phonon coupling. However, in all regimes the
gate-voltage dependence of the zero temperature conductance is found to be
qualitatively the same as in the model with no coupling to the vibrational
mode.


title:
Agile low phase noise radio-frequency sine wave generator applied to
  experiments on ultracold atoms

abstract:
  We report on the frequency performance of a low cost (~500$) radio-frequency
sine wave generator, using direct digital synthesis (DDS) and a
field-programmable gate array (FPGA). The output frequency of the device may be
changed dynamically to any arbitrary value ranging from DC to 10 MHz without
any phase slip. Sampling effects are substantially reduced by a high sample
rate, up to 1 MHz, and by a large memory length, more than 2.10^5 samples. By
using a low noise external oscillator to clock the DDS, we demonstrate a phase
noise as low as that of the master clock, that is at the level of -113
dB.rad^2/Hz at 1 Hz from the carrier for an output frequency of 3.75 MHz. The
device is successfully used to confine an ultracold atomic cloud of rubidium 87
in a RF-based trap, and there is no extra heating from the RF source.


title:
Growth rates for geometric complexities and counting functions in
  polygonal billiards

abstract:
  We introduce a new method for estimating the growth of various quantities
arising in dynamical systems. We apply our method to polygonal billiards on
surfaces of constant curvature. For instance, we obtain power bounds of degree
two plus epsilon in length for the number of billiard orbits between almost all
pairs of points in a planar polygon.


title: Information-Based Asset Pricing

abstract:
  A new framework for asset price dynamics is introduced in which the concept
of noisy information about future cash flows is used to derive the price
processes. In this framework an asset is defined by its cash-flow structure.
Each cash flow is modelled by a random variable that can be expressed as a
function of a collection of independent random variables called market factors.
With each such "X-factor" we associate a market information process, the values
of which are accessible to market agents. Each information process is a sum of
two terms; one contains true information about the value of the market factor;
the other represents "noise". The noise term is modelled by an independent
Brownian bridge. The market filtration is assumed to be that generated by the
aggregate of the independent information processes. The price of an asset is
given by the expectation of the discounted cash flows in the risk-neutral
measure, conditional on the information provided by the market filtration. When
the cash flows are the dividend payments associated with equities, an explicit
model is obtained for the share-price, and the prices of options on
dividend-paying assets are derived. Remarkably, the resulting formula for the
price of a European call option is of the Black-Scholes-Merton type. The
information-based framework also generates a natural explanation for the origin
of stochastic volatility.


title: The Jumping Phenomenon of Hodge Numbers

abstract:
  Let $X$ be a compact complex manifold, consider a small deformation $\phi:
\mathcal{X} \to B$ of $X$, the dimension of the Dolbeault cohomology groups
$H^q(X_t,\Omega_{X_t}^p)$ may vary under this defromation. This paper will
study such phenomenons by studying the obstructions to deform a class in
$H^q(X,\Omega_X^p)$ with the parameter $t$ and get the formula for the
obstructions.


title: Strange dibaryon resonance in the anti-KNN--piYN system

abstract:
  Three-body resonances in the \bar{K}NN system have been studied within a
framework of the \bar{K}NN-\pi YN coupled hannel Faddeev equation. By solving
the three-body equation the energy dependence of the resonant \bar{K}N
amplitude is fully taken into account. The S-matrix pole has been investigated
from the eigenvalue of the kernel with the analytic continuation of the
scattering amplitude on the unphysical Riemann sheet. The \barKN interaction is
constructed from the leading order term of the chiral Lagrangian using
relativistic kinematics. The \Lambda(1405) resonance is dynamically generated
in this model, where the \bar{K}N interaction parameters are fitted to the data
of scattering length. As a result we find a three-body resonance of the strange
dibaryon system with binding energy, B~79 MeV, and width, \Gamma~74 MeV. The
energy of the three-body resonance is found to be sensitive to the model of the
I=0 \barKN interaction.


title: SU(2) and SU(4) Kondo effect in double quantum dots

abstract:
  We investigate serial double quantum dot systems with on-site and inter-site
interaction by means of Sch\"onhammer-Gunnarsson projection-operator method.
The ground state is established by the competition between extended Kondo
phases and localized singlet phases in spi$ degrees of freedom. We present and
discuss different phases, as discerned by characteristic correlation functions.
We discuss also how different phases would be seen in linear transport
measurements.


title: V-cycle optimal convergence for DCT-III matrices

abstract:
  The paper analyzes a two-grid and a multigrid method for matrices belonging
to the DCT-III algebra and generated by a polynomial symbol. The aim is to
prove that the convergence rate of the considered multigrid method (V-cycle) is
constant independent of the size of the given matrix. Numerical examples from
differential and integral equations are considered to illustrate the claimed
convergence properties.


title:
Improved Measurement of the Positive Muon Lifetime and Determination of
  the Fermi Constant

abstract:
  The mean life of the positive muon has been measured to a precision of 11 ppm
using a low-energy, pulsed muon beam stopped in a ferromagnetic target, which
was surrounded by a scintillator detector array. The result, tau_mu =
2.197013(24) us, is in excellent agreement with the previous world average. The
new world average tau_mu = 2.197019(21) us determines the Fermi constant G_F =
1.166371(6) x 10^-5 GeV^-2 (5 ppm). Additionally, the precision measurement of
the positive muon lifetime is needed to determine the nucleon pseudoscalar
coupling g_P.


title: Some notes on analytic torsion of the Rumin complex on contact manifolds

abstract:
  We propose a definition for analytic torsion of the Rumin complex on contact
manifolds. This is given by the derivative at zero of a well-chosen combination
of zeta functions of a fourth-order modified Rumin Laplacian. The regular value
at zero (before differentiation) of this well-chosen combination of zeta
functions is shown to be a contact invariant. The variation of our analytic
torsion is given as the integral of local terms, together with a global term
coming from the null-space of the Laplacian.


title:
Universal 2+1-Dimensional Plane Equations in General Relativity and
  Evolutions of Disk Nebula

abstract:
  The general relativity is the base for any exact evolutionary theory of large
scale structures. We calculate the universal 2+1-dimensional plane equations of
gravitational field in general relativity. Based on the equations, the
evolutions of disk nebula are discussed. A system of nebula can form binary
stars or single star for different conditions. While any simplified linear
theory forms only a single star system. It is proved that the nonlinear
interactions are very general, so the binary stars are also common.


title: Nuclear matter in the crust of neutron stars

abstract:
  The properties of inhomogeneous nuclear matter are investigated considering
the self-consistent Skyrme Hartree-Fock approach with inclusion of pairing
correlations. For a comparison we also consider a relativistic mean field
approach. The inhomogeneous infinite matter is described in terms of cubic
Wigner-Seitz cells, which leads to a smooth transition to the limit of
homogeneous nuclear matter. The possible existence of various structures in the
so-called pasta phase is investigated within this self-consistent approach and
a comparison is made to results obtained within the Thomas-Fermi approximation.
Results for the proton abundances and the pairing properties are discussed for
densities for which clustering phenomena are obtained.


title: Electromagnetic Higgs production

abstract:
  The cross section for central diffractive Higgs production is calculated, for
the LHC range of energies. The graphs for the possible mechanisms for Higgs
production, through pomeron fusion and photon fusions are calculated for all
possibilities allowed by the standard model. The cross section for central
diffractive Higgs production through pomeron fusion, must be multiplied by a
factor for the survival probability, to isolate the Higgs signal and reduce the
background. Due to the small value of the survival probability $\Lb 4 \times
10^{-3}\Rb $, the cross sections for central diffractive Higgs production, in
the two cases for pomeron fusion and photon fusion, are competitive.


title: Characterization of Closed Vector Fields in Finsler Geometry

abstract:
  The $\pi$-exterior derivative ${\o}d$, which is the Finslerian generalization
of the (usual) exterior derivative $d$ of Riemannian geometry, is defined. The
notion of a ${\o}d$-closed vector field is introduced and investigated. Various
characterizations of ${\o}d$-closed vector fields are established. Some results
concerning ${\o}d$-closed vector fields in relation to certain special Finsler
spaces are obtained.


title: Pure inductive limit state and Kolmogorov's property

abstract:
  Let $(\clb,\lambda_t,\psi)$ be a $C^*$-dynamical system where $(\lambda_t: t
\in \IT_+)$ be a semigroup of injective endomorphism and $\psi$ be an
$(\lambda_t)$ invariant state on the $C^*$ subalgebra $\clb$ and $\IT_+$ is
either non-negative integers or real numbers. The central aim of this
exposition is to find a useful criteria for the inductive limit state $\clb
\raro^{\lambda_t} \clb$ canonically associated with $\psi$ to be pure. We
achieve this by exploring the minimal weak forward and backward Markov
processes associated with the Markov semigroup on the corner von-Neumann
algebra of the support projection of the state $\psi$ to prove that
Kolmogorov's property [Mo2] of the Markov semigroup is a sufficient condition
for the inductive state to be pure. As an application of this criteria we find
a sufficient condition for a translation invariant factor state on a one
dimensional quantum spin chain to be pure. This criteria in a sense complements
criteria obtained in [BJKW,Mo2] as we could go beyond lattice symmetric states.


title:
Classical nucleation theory in ordering alloys precipitating with L12
  structure

abstract:
  By means of low-temperature expansions (LTEs), the nucleation free energy and
the precipitate interface free energy are expressed as functions of the
solubility limit for alloys which lead to the precipitation of a stoichiometric
L12 compound such as Al-Sc or Al-Zr alloys. Classical nucleation theory is then
used to obtain a simple expression of the nucleation rate whose validity is
demonstrated by a comparison with atomic simulations. LTEs also explain why
simple mean-field approximation like the Bragg-Williams approximation fails to
predict correct nucleation rates in such an ordering alloy.


title: Jones index of a quantum dynamical semigroup

abstract:
  In this paper we consider a semigroup of completely positive maps
$\tau=(\tau_t,t \ge 0)$ with a faithful normal invariant state $\phi$ on a
type-$II_1$ factor $\cla_0$ and propose an index theory. We :achieve this via a
more general Kolmogorov's type of construction for stationary Markov processes
which naturally associate a nested isomorphic von-Neumann algebras. In
particular this construction generalizes well known Jones construction
associated with a sub-factor of type-II$_1$ factor.


title:
Vacuum Polarization by a Magnetic Flux Tube at Finite Temperature in the
  Cosmic String Spacetime

abstract:
  In this paper we analyse the effect produced by the temperature in the vacuum
polarization associated with charged massless scalar field in the presence of
magnetic flux tube in the cosmic string spacetime. Three different
configurations of magnetic fields are taken into account: $(i)$ a homogeneous
field inside the tube, $(ii)$ a field proportional to $1/r$ and $(iii)$ a
cylindrical shell with $\delta$-function. In these three cases, the axis of the
infinitely long tube of radius $R$ coincides with the cosmic string. Because
the complexity of this analysis in the region inside the tube, we consider the
thermal effect in the region outside. In order to develop this analysis, we
construct the thermal Green function associated with this system for the three
above mentioned situations considering points in the region outside the tube.
We explicitly calculate in the high-temperature limit, the thermal average of
the field square and the energy-momentum tensor.


title: Single pion electro-- and neutrinoproduction on heavy targets

abstract:
  We present a calculation of single pion electroproduction cross sections on
heavy targets in the kinematic region of the Delta(1232) resonance. Final state
interactions of the pions are taken into account using the pion multiple
scattering model of Adler, Nussinov and Paschos (ANP model). For
electroproduction and neutral current reactions we obtain results for carbon,
oxygen, argon and iron targets and find a significant reduction of the
W-spectra for pi^0 as compared to the free nucleon case. On the other hand, the
charged pion spectra are only little affected by final state interactions.
Measurements of such cross sections with the CLAS detector at JLAB could help
to improve our understanding of pion rescattering effects and serve as
important/valuable input for calculations of single pion neutrinoproduction on
heavy targets relevant for current and future long baseline neutrino
experiments. Two ratios, in Eq. (3.8) and (3.10), will test important
properties of the model.


title: Yukawa's Pion, Low-Energy QCD and Nuclear Chiral Dynamics

abstract:
  A survey is given of the evolution from Yukawa's early work, via the
understanding of the pion as a Nambu-Goldstone boson of spontaneously broken
chiral symmetry in QCD, to modern developments in the theory of the nucleus
based on the chiral effective field theory representing QCD in its low-energy
limit.


title:
Competition between local and nonlocal dissipation effects in
  two-dimensional quantum Josephson junction arrays

abstract:
  We discuss the local and nonlocal dissipation effects on the existence of the
global phase coherence transitions in two dimensional Josephson-coupled
junctions. The quantum phase transitions are also examined for various lattice
geometries: square, triangular and honeycomb. The T=0 superconductor-insulator
phase transition is analyzed as a function of several control parameters which
include self-capacitance and junction capacitance and both local and nonlocal
dissipation effects. We found the critical value of the nonlocal dissipation
parameter \alpha_{1} depends on a geometry of the lattice. The critical value
of the normal state conductance seems to be difficult to obtain experimentally
if we take into consideration different damping mechanisms which are presented
in real physical systems.


title: Substrate-induced bandgap in graphene on hexagonal boron nitride

abstract:
  We determine the electronic structure of a graphene sheet on top of a
lattice-matched hexagonal boron nitride (h-BN) substrate using ab initio
density functional calculations. The most stable configuration has one carbon
atom on top of a boron atom, the other centered above a BN ring. The resulting
inequivalence of the two carbon sites leads to the opening of a gap of 53 meV
at the Dirac points of graphene and to finite masses for the Dirac fermions.
Alternative orientations of the graphene sheet on the BN substrate generate
similar band gaps and masses. The band gap induced by the BN surface can
greatly improve room temperature pinch-off characteristics of graphene-based
field effect transistors.


title: Coherent dynamics of domain formation in the Bose Ferromagnet

abstract:
  We present a theory to describe domain formation observed very recently in a
quenched Rb-87 gas, a typical ferromagnetic spinor Bose system. An overlap
factor is introduced to characterize the symmetry breaking of M_F=\pm 1
components for the F=1 ferromagnetic condensate. We demonstrate that the domain
formation is a co-effect of the quantum coherence and the thermal relaxation. A
thermally enhanced quantum-oscillation is observed during the dynamical process
of the domain formation. And the spatial separation of domains leads to
significant decay of the M_F=0 component fraction in an initial M_F=0
condensate.


title: A Wave-function for Stringy Universes

abstract:
  We define a wave-function for string theory cosmological backgrounds. We give
a prescription for computing its norm following an earlier analysis within
general relativity. Under Euclidean continuation, the cosmologies we discuss in
this paper are described in terms of compact parafermionic worldsheet systems.
To define the wave-function we provide a T-fold description of the
parafermionic conformal field theory, and of the corresponding string
cosmology. In specific examples, we compute the norm of the wave-function and
comment on its behavior as a function of moduli.


title:
Query on Negative Temperature, Internal Interactions and Decrease of
  Entropy

abstract:
  After negative temperature is restated, we find that it will derive
necessarily decrease of entropy. Negative temperature is based on the Kelvin
scale and the condition dU>0 and dS<0. Conversely, there is also negative
temperature for dU<0 and dS>0. But, negative temperature is contradiction with
usual meaning of temperature and with some basic concepts of physics and
mathematics. It is a question in nonequilibrium thermodynamics. We proposed a
possibility of decrease of entropy due to fluctuation magnified and internal
interactions in some isolated systems. From this we discuss some possible
examples and theories.


title:
Absence of the Fifth Force Problem in a Model with Spontaneously Broken
  Dilatation Symmetry

abstract:
  A scale invariant model containing dilaton $\phi$ and dust (as a model of
matter) is studied where the shift symmetry $\phi\to\phi +const.$ is
spontaneously broken at the classical level due to intrinsic features of the
model. The dilaton to matter coupling "constant" $f$ appears to be dependent of
the matter density. In normal conditions, i.e. when the matter energy density
is many orders of magnitude larger than the dilaton contribution to the dark
energy density, $f$ becomes less than the ratio of the "mass of the vacuum" in
the volume occupied by the matter to the Planck mass. The model yields this
kind of "Archimedes law" without any especial (intended for this) choice of the
underlying action and without fine tuning of the parameters. The model not only
explains why all attempts to discover a scalar force correction to Newtonian
gravity were unsuccessful so far but also predicts that in the near future
there is no chance to detect such corrections in the astronomical measurements
as well as in the specially designed fifth force experiments on intermediate,
short (like millimeter) and even ultrashort (a few nanometer) ranges. This
prediction is alternative to predictions of other known models.


title: Dark matter caustics and the enhancement of self-annihilation flux

abstract:
  Cold dark matter haloes are populated by caustics, which are yet to be
resolved in N-body simulations or observed in the Universe. Secondary infall
model provides a paradigm for the study of caustics in "typical" haloes
assuming that they have had no major mergers and have grown only by smooth
accretion. This is a particular characteristic of the smallest dark matter
haloes of about 10^{-5} Mo, which although "atypical" contain no substructures
and could have survived until now with no major mergers. Thus using this model
as the first guidline, we evaluate the neutralino self-annihilation flux for
these haloes. Our results show that caustics could leave a distinct sawteeth
signature on the differential and cumulative fluxes coming from the outer
regions of these haloes. The total annihilation signal from the regions away
from the centre can be boosted by about forty percents.


title:
Search for a Higgs boson produced in association with a Z boson in ppbar
  collisions

abstract:
  We describe a search for the standard model Higgs boson with a mass of 105
GeV/c^2 to 145 GeV/c^2 in data corresponding to an integrated luminosity of
approximately 450 pb^{-1} collected with the D0 detector at the Fermilab
Tevatron ppbar collider at a center-of-mass energy of 1.96 TeV. The Higgs boson
is required to be produced in association with a Z boson, and the Z boson is
required to decay to either electrons or muons with the Higgs boson decaying to
a bbbar pair. The data are well described by the expected background, leading
to 95% confidence level cross section upper limits sigma(\ppbar\to ZH)x
B(H\to\bbbar) in the range of 3.1 pb to 4.4 pb.


title:
Geometry of Parallelizable Manifolds in the Context of Generalized
  Lagrange Spaces

abstract:
  In this paper, we deal with a generalization of the geometry of
parallelizable manifolds, or the absolute parallelism (AP-) geometry, in the
context of generalized Lagrange spaces. All geometric objects defined in this
geometry are not only functions of the positional argument $x$, but also depend
on the directional argument $y$. In other words, instead of dealing with
geometric objects defined on the manifold $M$, as in the case of classical
AP-geometry, we are dealing with geometric objects in the pullback bundle
$\pi^{-1}(TM)$ (the pullback of the tangent bundle $TM$ by $ \pi: T
M\longrightarrow M$). Many new geometric objects, which have no counterpart in
the classical AP-geometry, emerge in this more general context. We refer to
such a geometry as generalized AP-geometry (GAP-geometry). In analogy to
AP-geometry, we define a $d$-connection in $\pi^{-1}(TM)$ having remarkable
properties, which we call the canonical $d$-connection, in terms of the unique
torsion-free Riemannian $d$-connection. In addition to these two
$d$-connections, two more $d$-connections are defined, the dual and the
symmetric $d$-connections. Our space, therefore, admits twelve curvature
tensors (corresponding to the four defined $d$-connections), three of which
vanish identically. Simple formulae for the nine non-vanishing curvatures
tensors are obtained, in terms of the torsion tensors of the canonical
$d$-connection. The different $W$-tensors admitted by the space are also
calculated. All contractions of the $h$- and $v$-curvature tensors and the
$W$-tensors are derived. Second rank symmetric and skew-symmetric tensors,
which prove useful in physical applications, are singled out.


title:
Fluctuation dynamo and turbulent induction at low magnetic Prandtl
  numbers

abstract:
  This paper is a detailed report on a programme of simulations used to settle
a long-standing issue in the dynamo theory and demonstrate that the fluctuation
dynamo exists in the limit of large magnetic Reynolds number Rm>>1 and small
magnetic Prandtl number Pm<<1. The dependence of the critical Rm_c vs. the
hydrodynamic Reynolds number Re is obtained for 1<Re<6700. In the limit Pm<<1,
Rm_c is ~3 times larger than for Pm>1. The stability curve Rm_c(Re) (and, it is
argued, the nature of the dynamo) is substantially different from the case of
the simulations and liquid-metal experiments with a mean flow. It is not as yet
possible to determine numerically whether the growth rate is ~Rm^{1/2} in the
limit Re>>Rm>>1, as should be the case if the dynamo is driven by the
inertial-range motions. The magnetic-energy spectrum in the low-Pm regime is
qualitatively different from the Pm>1 case and appears to develop a negative
spectral slope, although current resolutions are insufficient to determine its
asymptotic form. At 1<Rm<Rm_c, the magnetic fluctuations induced via the
tangling by turbulence of a weak mean field are investigated and the
possibility of a k^{-1} spectrum above the resistive scale is examined. At low
Rm<1, the induced fluctuations are well described by the quasistatic
approximation; the k^{-11/3} spectrum is confirmed for the first time in direct
numerical simulations.

categories: physics.flu-dyn astro-ph nlin.CD physics.plasm-ph