title:
Shear stresses of colloidal dispersions at the glass transition in
  equilibrium and in flow

abstract:
  We consider a model dense colloidal dispersion at the glass transition, and
investigate the connection between equilibrium stress fluctuations, seen in
linear shear moduli, and the shear stresses under strong flow conditions far
from equilibrium, viz. flow curves for finite shear rates. To this purpose
thermosensitive core-shell particles consisting of a polystyrene core and a
crosslinked poly(N-isopropylacrylamide)(PNIPAM) shell were synthesized. Data
over an extended range in shear rates and frequencies are compared to
theoretical results from integrations through transients and mode coupling
approaches. The connection between non-linear rheology and glass transition is
clarified. While the theoretical models semi-quantitatively fit the data taken
in fluid states and the predominant elastic response of glass, a yet
unaccounted dissipative mechanism is identified in glassy states.


title: The DAMA/LIBRA apparatus

abstract:
  The $\simeq$ 250 kg highly radiopure NaI(Tl) DAMA/LIBRA apparatus, running at
the Gran Sasso National Laboratory (LNGS) of the I.N.F.N., is described.


title:
Gold nanoparticle assemblies: Interplay between thermal effects and
  optical response

abstract:
  The optical response of materials based on gold nanoparticle assemblies
depends on many parameters regarding both material morphology and light
excitation characteristics. In this paper, the interplay between the optical
and thermal responses of such media is particularly investigated under its
theoretical aspect. Both conventional and original modeling approaches are
presented and applied to concrete cases. We first show how the interaction of
light with matrix-embedded gold nanoparticles can result in the generation of
thermal excitations through different energy exchange mechanisms. We then
describe how thermal processes can affect the optical response of a
nanoparticle assembly. Finally, we connect both aspects and point out their
involvement in the nonlinear optical response of nanocomposite media. This
allows us to tackle two key issues in the field of third-order nonlinear
properties of gold nanoparticles: The influence of the generalized thermal lens
in the long laser pulse regime and the hot electron contribution to the gold
particle intrinsic third-order susceptibility, including its spectral
dispersion and intensity-dependence. Additionally, we demonstrate the possible
significant influence of the heat carrier ballistic regime and phonon
rarefaction in the cooling dynamics of an embedded gold nanoparticle subsequent
to ultrafast pulsed laser excitation.


title:
Coherent generation of nonclassical light on a chip via photon-induced
  tunneling and blockade

abstract:
  We report the observation of nonclassical light generated via photon blockade
in a photonic crystal cavity with a strongly coupled quantum dot. By tuning the
frequency of the probe laser with respect to the cavity and quantum dot
resonance we can probe the system in either photon blockade or photon-induced
tunneling regime. The transition from one regime to the other is confirmed by
the measurement of the second order correlation that changes from anti-bunching
to bunching.


title: First results from DAMA/LIBRA and the combined results with DAMA/NaI

abstract:
  The highly radiopure $\simeq$ 250 kg NaI(Tl) DAMA/LIBRA set-up is running at
the Gran Sasso National Laboratory of the I.N.F.N.. In this paper the first
result obtained by exploiting the model independent annual modulation signature
for Dark Matter (DM) particles is presented. It refers to an exposure of 0.53
ton$\times$yr. The collected DAMA/LIBRA data satisfy all the many peculiarities
of the DM annual modulation signature. Neither systematic effects nor side
reactions can account for the observed modulation amplitude and
contemporaneously satisfy all the several requirements of this DM signature.
Thus, the presence of Dark Matter particles in the galactic halo is supported
also by DAMA/LIBRA and, considering the former DAMA/NaI and the present
DAMA/LIBRA data all together (total exposure 0.82 ton$\times$yr), the presence
of Dark Matter particles in the galactic halo is supported at 8.2 $\sigma$
C.L..


title:
Automated Classification of ELODIE Stellar Spectral Library Using
  Probabilistic Artificial Neural Networks

abstract:
  A Probabilistic Neural Network model has been used for automated
classification of ELODIE stellar spectral library consisting of about 2000
spectra into 158 known spectro-luminosity classes. The full spectra with 561
flux bins and a PCA reduced set of 57, 26 and 16 components have been used for
the training and test sessions. The results shows a spectral type
classification accuracy of 3.2 sub-spectral type and luminosity class accuracy
of 2.7 for the full spectra and an accuracy of 3.1 and 2.6 respectively with
the PCA set. This technique will be useful for future upcoming large data bases
and their rapid classification.


title: Rare B and Charm Decays at the Tevatron

abstract:
  The measurements of rare decays are highly sensitive to physics beyond the
standard model. In this article limits on the branching ratios of the decays
B0s -> mu+mu-, D0 -> mu+mu- and D+ -> pi+mu+mu- are presented. Furthermore the
first measurement of the branching fraction and CP asymmetry of Lambda_b -> p
pi- and Lambda_b -> p K- decays is described. Data samples with an integrated
luminosity of up to 2/fb collected at the Tevatron ppbar-collider at
sqrt(s)=1.96 TeV were used in these analyses. The results are consistent with
the standard model predictions and tighten the constraints on new physics
models.


title: Non-standard interactions using the OPERA experiment

abstract:
  We investigate the implications of non-standard interactions on neutrino
oscillations in the OPERA experiment. In particular, we study the non-standard
interaction parameter $\epsilon_{\mu\tau}$. We show that the OPERA experiment
has a unique opportunity to reduce the allowed region for this parameter
compared with other experiments such as the MINOS experiment, mostly due to the
higher neutrino energies in the CNGS beam compared to the NuMI beam. We find
that OPERA is mainly sensitive to a combination of standard and non-standard
parameters and that a resulting anti-resonance effect could suppress the
expected number of events. Furthermore, we show that running OPERA for five
years each with neutrinos and anti-neutrinos would help in resolving the
degeneracy between the standard parameters and $\epsilon_{\mu\tau}$. This
scenario is significantly better than the scenario with a simple doubling of
the statistics by running with neutrinos for ten years.


title: Universal recursive formulae for Q-curvatures

abstract:
  We formulate and discuss two conjectures concerning recursive formulae for
Branson's $Q$-curvatures. The proposed formulae describe all $Q$-curvatures on
manifolds of all even dimensions in terms of respective lower order
$Q$-curvatures and lower order GJMS-operators. They are universal in the
dimension of the underlying space. The recursive formulae are generated by an
algorithm which rests on the theory of residue families. We attempt to resolve
the algorithm by formulating a conjectural description of the coefficients in
the recursive formulae in terms of interpolation polynomials associated to
compositions of natural numbers. We prove that the conjectures cover $Q_4$ and
$Q_6$ for general metrics, and $Q_8$ for conformally flat metrics. The result
for $Q_8$ is proved here for the first time. Moreover, we display explicit
(conjectural) formulae for $Q$-curvatures of order up to 16, and test high
order cases for round spheres and Einstein metrics.


title: Topological Disorder in Spin Models on Hierarchical Lattices

abstract:
  A general approach for the description of spin systems on hierarchial
lattices with coordination number $q$ as a dynamical variable is proposed. The
ferromagnetic Ising model on the Bethe lattice was studied as a simple example
demonstrating our method. The annealed and partly annealed versions of disorder
concerned with the lattice coordination number are invented and discussed.
Recurrent relations are obtained for the evaluation of magnetization. The
magnetization is calculated for the particular disorder choices, $q=2,3$ and
$q=3,4$. A nontrivial localization of critical point is revealed.


title:
Fast calculation of the electrostatic potential in ionic crystals by
  direct summation method

abstract:
  An efficient real space method is derived for the evaluation of the
Madelung's potential of ionic crystals. The proposed method is an extension of
the Evjen's method. It takes advantage of a general analysis for the potential
convergence in real space. Indeed, we show that the series convergence is
exponential as a function of the number of annulled multipolar momenta in the
unit cell. The method proposed in this work reaches such an exponential
convergence rate. Its efficiency is comparable to the Ewald's method, however
unlike the latter, it uses only simple algebraic functions.


title: Anisotropic minimal conductivity of graphene bilayers

abstract:
  Fermi line of bilayer graphene at zero energy is transformed into four
separated points positioned trigonally at the corner of the hexagonal first
Brillouin zone. We show that as a result of this trigonal splitting the minimal
conductivity of an undoped bilayer graphene strip becomes anisotropic with
respect to the orientation $\theta$ of the connected electrodes and finds a
dependence on its length $L$ on the characteristic scale $\ell=\pi/\Delta
k\simeq 50 nm$ determined by the inverse of k-space distance of two Dirac
points. The minimum conductivity increases from a universal isotropic value
$\sigma^{min}_{\bot}=(8/\pi)e^2/h$ for a short strip $L\ll \ell$ to a higher
anisotropic value for longer strips, which in the limit of $L\gg \ell$ varies
from $(7/3)\sigma^{min}_{\bot}$ at $\theta=0$ to $3\sigma^{min}_{\bot}$ over an
angle range $\Delta \theta\sim \ell/L$.


title: Solvent viscosity dependence for enzymatic reactions

abstract:
  A mechanism for relationship of solvent viscosity with reaction rate constant
at enzyme action is suggested. It is based on fluctuations of electric field in
enzyme active site produced by thermally equilibrium rocking (cranckshaft
motion) of the rigid plane (in which the dipole moment $\approx 3.6 D$ lies) of
a favourably located and oriented peptide group (or may be a few of them). Thus
the rocking of the plane leads to fluctuations of the electric field of the
dipole moment. These fluctuations can interact with the reaction coordinate
because the latter in its turn has transition dipole moment due to separation
of charges at movement of the reacting system along it. The rocking of the
plane of the peptide group is sensitive to the microviscosity of its
environment in protein interior and the latter is a function of the solvent
viscosity. Thus we obtain an additional factor of interrelationship for these
characteristics with the reaction rate constant. We argue that due to the
properties of the cranckshaft motion the frequency spectrum of the electric
field fluctuations has a sharp resonance peak at some frequency and the
corresponding Fourier mode can be approximated as oscillations. We employ a
known result from the theory of thermally activated escape with periodic
driving to obtain the reaction rate constant and argue that it yields reliable
description of the preexponent where the dependence on solvent viscosity
manifests itself. The suggested mechanism is shown to grasp the main feature of
this dependence known from the experiment and satisfactorily yields the upper
limit of the fractional index of a power in it.


title: Neutrino-induced pion production from nuclei at medium energies

abstract:
  We present a fully relativistic formalism for describing neutrino-induced
$\Delta$-mediated single-pion production from nuclei. We assess the ambiguities
stemming from the $\Delta$ interactions. Variations in the cross sections of
over 10% are observed, depending on whether or not magnetic-dipole dominance is
assumed to extract the vector form factors. These uncertainties have a direct
impact on the accuracy with which the axial-vector form factors can be
extracted. Different predictions for $C_5^A(Q^2)$ induce up to 40-50% effects
on the $\Delta$-production cross sections. To describe the nucleus, we turn to
a relativistic plane-wave impulse approximation (RPWIA) using realistic
bound-state wave functions derived in the Hartree approximation to the
$\sigma$-$\omega$ Walecka model. For neutrino energies larger than 1 GeV, we
show that a relativistic Fermi-gas model with appropriate binding-energy
correction produces comparable results as the RPWIA which naturally includes
Fermi motion, nuclear-binding effects and the Pauli exclusion principle.
Including $\Delta$ medium modifications yields a 20 to 25% reduction of the
RPWIA cross section. The model presented in this work can be naturally extended
to include the effect of final-state interactions in a relativistic and
quantum-mechanical way. Guided by recent neutrino-oscillation experiments, such
as MiniBooNE and K2K, and future efforts like MINER$\nu$A, we present $Q^2$,
$W$, and various semi-inclusive distributions, both for a free nucleon and
carbon, oxygen and iron targets.


title: Inducing energy gaps in graphene monolayer and bilayer

abstract:
  In this paper we propose a mechanism for the induction of energy gaps in the
spectrum of graphene and its bilayer, when both these materials are covered
with water and ammonia molecules. The energy gaps obtained are within the range
20-30 meV, values compatible to those found in experimental studies of graphene
bilayer. We further show that the binding energies are large enough for the
adsorption of the molecules to be maintained even at room temperature.


title: Boosting Algorithms: Regularization, Prediction and Model Fitting

abstract:
  We present a statistical perspective on boosting. Special emphasis is given
to estimating potentially complex parametric or nonparametric models, including
generalized linear and additive models as well as regression models for
survival analysis. Concepts of degrees of freedom and corresponding Akaike or
Bayesian information criteria, particularly useful for regularization and
variable selection in high-dimensional covariate spaces, are discussed as well.
The practical aspects of boosting procedures for fitting statistical models are
illustrated by means of the dedicated open-source software package mboost. This
package implements functions which can be used for model fitting, prediction
and variable selection. It is flexible, allowing for the implementation of new
boosting algorithms optimizing user-specified loss functions.


title:
Topological degeneracy and vortex manipulation in Kitaev's honeycomb
  model

abstract:
  The classification of loop symmetries in Kitaev's honeycomb lattice model
provides a natural framework to study the abelian topological degeneracy. We
derive a perturbative low-energy effective Hamiltonian, that is valid to all
orders of the expansion and for all possible toroidal configurations. Using
this form we demonstrate at what order the system's topological degeneracy is
lifted by finite size effects and note that in the thermodynamic limit it is
robust to all orders. Further, we demonstrate that the loop symmetries
themselves correspond to the creation, propagation and annihilation of
fermions. Importantly, we note that these fermions, made from pairs of
vortices, can be moved with no additional energy cost.


title:
Detection Probability of Terrestrial Radio Signals by a Hostile
  Super-civilization

abstract:
  Comparison of the total number of the radar astronomy transmissions with
respect to that used for sending messages to extra-terrestrial civilizations
reveals that the probability of detection of the radio signals to
extraterrestrials (ETs) is one million times smaller than that of the radar
signals used to study planets and asteroids in the Solar System.


title: Brownian soliton motion

abstract:
  We reveal fundamental analogies between soliton dynamics in light-induced
random photonic lattices and Brownian motion of particles. In particular, we
discover that the average squared soliton displacement increases linearly with
distance after an initial ballistic regime of propagation. We also find that in
shallow lattices the average soliton displacement grows linearly with
increasing lattice depth.


title: $0^{++}$ Resonances Observed at BES

abstract:
  In last 10 years, $0^{++}$ resonances have been observed and studied at BES
in many processes, such as $J/\psi\to\gamma\pi^+\pi^-\pi^+\pi^-$,
$\gamma\pi^+\pi^-$, $\gamma\pi^0\pi^0$, $\gamma K^+K^-$, $\gamma K_SK_S$,
$\gamma\omega\phi$, $\omega\pi^+\pi^-$, $\omega K^+K^-$, $\phi\pi^+\pi^-$,
$\phi K^+K^-$, $\psi(2S)\to J/\psi\pi^+\pi^-$, $\chi_{c0}\to\pi^+\pi^-K^+K^-$,
$\pi^+\pi^-\pi^+\pi^-$ etc.. The results on $0^{++}$ resonances observed at BES
are reviewed.


title:
Comment: Boosting Algorithms: Regularization, Prediction and Model
  Fitting

abstract:
  The authors are doing the readers of Statistical Science a true service with
a well-written and up-to-date overview of boosting that originated with the
seminal algorithms of Freund and Schapire. Equally, we are grateful for
high-level software that will permit a larger readership to experiment with, or
simply apply, boosting-inspired model fitting. The authors show us a world of
methodology that illustrates how a fundamental innovation can penetrate every
nook and cranny of statistical thinking and practice. They introduce the reader
to one particular interpretation of boosting and then give a display of its
potential with extensions from classification (where it all started) to least
squares, exponential family models, survival analysis, to base-learners other
than trees such as smoothing splines, to degrees of freedom and regularization,
and to fascinating recent work in model selection. The uninitiated reader will
find that the authors did a nice job of presenting a certain coherent and
useful interpretation of boosting. The other reader, though, who has watched
the business of boosting for a while, may have quibbles with the authors over
details of the historic record and, more importantly, over their optimism about
the current state of theoretical knowledge. In fact, as much as ``the
statistical view'' has proven fruitful, it has also resulted in some ideas
about why boosting works that may be misconceived, and in some recommendations
that may be misguided. [arXiv:0804.2752]


title: Electron energy level statistics in graphene quantum dots

abstract:
  Motivated by recent experimental observations of size quantization of
electron energy levels in graphene quantum dots \cite{ponomarenko} we
investigate the level statistics in the simplest tight-binding model for
different dot shapes by computer simulation. The results are in a reasonable
agreement with the experiment which confirms qualitatively interpretation of
observed level statistics in terms of "Dirac billiards" without taking into
account many-body effects. It is shown that edge effects are in general
sufficient to produce the observed level distribution and that even strong bulk
disorder does not change the results drastically.


title:
Ground-state properties of few-Boson system in a one-dimensional hard
  wall potential with split

abstract:
  We carry out a detailed examination of the ground state property of few-boson
system in a one-dimensional hard wall potential with a $\delta -$ split in the
center. In the Tonks-Girardeau limit with infinite repulsion between particles,
we use the Bose-Fermi mapping to construct the exact $N-$ particle ground state
wavefunction which allows us to study the correlation properties accurately.
For the general case with finite inter-particle interaction, the exact
diagonalization method is exploited to study the ground-state density
distribution, occupation number distribution, and momentum distribution for
variable interaction strengths and barrier heights. The secondary peaks in the
momentum distribution reveal the interference between particles on the two
sides of the split, which is more prominent for large barrier strength and
small interaction strength.


title: Near band gap photoluminescence properties of hexagonal boron nitride

abstract:
  Near band-gap luminescence (hnu > 5 eV) of hexagonal boron nitride has been
studied by means of the time- and energy-resolved photoluminescence
spectroscopy method. Two emissions have been observed at 5.5 eV and 5.3 eV. The
high-energy emission at 5.5 eV is composed of fixed sub-bands assigned to bound
excitons at 5.47 eV, 5.56 eV and 5.61 eV. The non-structured low-energy
emission at 5.3 eV undergoes a large blue shift (up to 120 meV) with a linear
slope <1 with increasing excitation energy Eexc. At Eexc>5.7 eV, the band
position is fixed and marks the transition from the Raman to the
photoluminescence regime. We assign the 5.3 eV band to quasi donor-acceptor
pair (q-DAP) states due to electrostatic band fluctuations induced by charged
defects. The shift is explained by photo-induced neutralization of charged
defect states. The absence of contribution to the q-DAP luminescence from
exciton suggests the existence of a large exciton binding energy, which is
qualitatively consistent with theoretical predictions.


title: The FFX Correlator

abstract:
  We established a new algorithm for correlation process in radio astronomy.
This scheme consists of the 1st-stage Fourier Transform as a filter and the
2nd-stage Fourier Transform for spectroscopy. The "FFX" correlator stands for
Filter and FX architecture, since the 1st-stage Fourier Transform is performed
as a digital filter, and the 2nd-stage Fourier Transform is performed as a
conventional FX scheme. We developed the FFX correlator hardware not only for
the verification of the FFX scheme algorithm but also for the application to
the Atacama Submillimeter Telescope Experiment (ASTE) telescope toward
high-dispersion and wideband radio observation at submillimeter wavelengths. In
this paper, we present the principle of the FFX correlator and its properties,
as well as the evaluation results with the production version.


title: Fast Convergence of Path Integrals for Many-body Systems

abstract:
  We generalize a recently developed method for accelerated Monte Carlo
calculation of path integrals to the physically relevant case of generic
many-body systems. This is done by developing an analytic procedure for
constructing a hierarchy of effective actions leading to improvements in
convergence of $N$-fold discretized many-body path integral expressions from
1/N to $1/N^p$ for generic $p$. In this paper we present explicit solutions
within this hierarchy up to level $p=5$. Using this we calculate the low lying
energy levels of a two particle model with quartic interactions for several
values of coupling and demonstrate agreement with analytical results governing
the increase in efficiency of the new method. The applicability of the
developed scheme is further extended to the calculation of energy expectation
values through the construction of associated energy estimators exhibiting the
same speedup in convergence.


title: On Oliver's p-group conjecture

abstract:
  Let S be a p-group for an odd prime p. Bob Oliver conjectures that a certain
characteristic subgroup X(S) always contains the Thompson subgroup J(S). We
obtain a reformulation of the conjecture as a statement about modular
representations of p-groups. Using this we verify Oliver's conjecture for
groups where S/X(S) has nilpotence class at most two.


title: Schur-Weyl duality as an instrument of Gauge-String duality

abstract:
  A class of mathematical dualities have played a central role in mapping
states in gauge theory to states in the spacetime string theory dual. This
includes the classical Schur-Weyl duality between symmetric groups and Unitary
groups, as well as generalisations involving Brauer and Hecke algebras. The
physical string dualities involved include examples from the AdS/CFT
correspondence as well as the string dual of two-dimensional Yang Mills.


title: Invariants at fixed and arbitrary energy. A unified geometric approach

abstract:
  Invariants at arbitrary and fixed energy (strongly and weakly conserved
quantities) for 2-dimensional Hamiltonian systems are treated in a unified way.
This is achieved by utilizing the Jacobi metric geometrization of the dynamics.
Using Killing tensors we obtain an integrability condition for quadratic
invariants which involves an arbitrary analytic function $S(z)$. For invariants
at arbitrary energy the function $S(z)$ is a second degree polynomial with real
second derivative. The integrability condition then reduces to Darboux's
condition for quadratic invariants at arbitrary energy. The four types of
classical quadratic invariants for positive definite 2-dimensional Hamiltonians
are shown to correspond to certain conformal transformations. We derive the
explicit relation between invariants in the physical and Jacobi time gauges. In
this way knowledge about the invariant in the physical time gauge enables one
to directly write down the components of the corresponding Killing tensor for
the Jacobi metric. We also discuss the possibility of searching for linear and
quadratic invariants at fixed energy and its connection to the problem of the
third integral in galactic dynamics. In our approach linear and quadratic
invariants at fixed energy can be found by solving a linear ordinary
differential equation of the first or second degree respectively.


title:
A characterization of domains in $\mathbf C^2$ with noncompact
  automorphism group

abstract:
  Let $D$ be a bounded domain in $\mathbf C^2$ with a non-compact group of
holomorphic automorphisms. Model domains for $D$ are obtained under the
hypothesis that at least one orbit accumulates at a boundary point near which
the boundary is smooth, real analytic and of finite type.


title: Configurational invariants of Hamiltonian systems

abstract:
  In this paper we explore the general conditions in order that a 2-dimensional
natural Hamiltonian system possess a second invariant which is a polynomial in
the momenta and is therefore Liouville integrable. We examine the possibility
that the invariant is preserved by the Hamiltonian flow on a given energy
hypersurface only (weak integrability) and derive the additional requirement
necessary to have conservation at arbitrary energy (strong integrability).
Using null complex coordinates, we show that the leading order coefficient of
the polynomial is an arbitrary holomorphic function in the case of weak
integrability and a polynomial in the coordinates in the strongly integrable
one. We review the results obtained so far with strong invariants up to degree
four and provide some new examples of weakly integrable systems with linear and
quadratic invariants.


title: Supersymmetry at and beyond the LHC

abstract:
  Prospects for SUSY discoveries and measurements at future colliders LHC and
ILC are discussed. The problem of reconstructing the underlying theory and SUSY
breaking mechanism is also addressed.


title:
Probing correlated phases of bosons in optical lattices via trap
  squeezing

abstract:
  We theoretically analyze the response properties of ultracold bosons in
optical lattices to the static variation of the trapping potential. We show
that, upon an increase of such potential (trap squeezing), the density
variations in a central region, with linear size of >~ 10 wavelengths, reflect
that of the bulk system upon changing the chemical potential: hence measuring
the density variations gives direct access to the bulk compressibility. When
combined with standard time-of-flight measurements, this approach has the
potential of unambiguously detecting the appearence of the most fundamental
phases realized by bosons in optical lattices, with or without further external
potentials: superfluid, Mott insulator, band insulator and Bose glass.


abstract:
  Comment on ``Boosting Algorithms: Regularization, Prediction and Model
Fitting'' [arXiv:0804.2752]


title:
Eigenvectors of the discrete Laplacian on regular graphs - a statistical
  approach

abstract:
  In an attempt to characterize the structure of eigenvectors of random regular
graphs, we investigate the correlations between the components of the
eigenvectors associated to different vertices. In addition, we provide
numerical observations, suggesting that the eigenvectors follow a Gaussian
distribution. Following this assumption, we reconstruct some properties of the
nodal structure which were observed in numerical simulations, but were not
explained so far. We also show that some statistical properties of the nodal
pattern cannot be described in terms of a percolation model, as opposed to the
suggested correspondence for eigenvectors of 2 dimensional manifolds.


title: A note on wealth in a volatile economy

abstract:
  I show that if the capital accumulation dynamics is stochastic a new term, in
addition to that given by accounting prices, has to be introduced in order to
derive a correct estimate of the genuine wealth of an economy. In a simple
model with multiplicative accumulation dynamics I show that: 1) the value
function is always a decreasing function of volatility 2) the accounting prices
are affected by volatility 3) the new term always gives a negative contribution
to wealth changes. I discuss results for models with constant elasticity
utility functions. When the elasticity of marginal utility is larger than one,
accounting prices increase with volatility whereas when it is less than one
accounting prices decrease with volatility. These conclusions are not altered
when adopting optimal saving rates.


title: A General Correspondence between Averages and Integrals

abstract:
  Recent work has generalized the Furstenberg correspondence between sets of
integers and dynamical systems to versions which involve sequences of finite
graphs or sequences of $L^\infty$ functions. We give a unified version of the
theorem subsuming all these generalizations.


title:
Andreev-Klein reflection in graphene ferromagnet-superconductor
  junctions

abstract:
  We show that Andreev reflection in a junction between ferromagnetic (F) and
superconducting (S) graphene regions is fundamentally different from the common
FS junctions. For a weakly doped F graphene with an exchange field $h$ larger
than its Fermi energy $E_{\rm F}$, Andreev reflection of massless Dirac
fermions is associated with a Klein tunneling through an exchange field p-n
barrier between two spin-split conduction and valence subbands. We find that
this Andreev-Klein process results in an enhancement of the subgap conductance
of a graphene FS junction by $h$ up to the point at which the conductance at
low voltages $eV\ll \Delta$ is greater than its value for the corresponding
non-ferromagnetic junction. We also demonstrate that the Andreev reflection can
be of retro or specular types in both convergent and divergent ways with the
reflection direction aligned, respectively, closer to and farther from the
normal to the junction as compared to the incidence direction.


title: Cosmological Scaling Solutions with Tachyon:Modified Gravity Model

abstract:
  Modifying the Einstein's gravity at large distance scales is one of the
interesting proposals to explain the late time acceleration of the universe. In
this paper, we analyse scaling solutions in modified gravity models where the
universe is sourced by a background matter fluid together with a tachyon type
scalar field. We describe a general prescription to calculate the scaling
potential in such models. Later on, we consider specific examples of
modifications and apply our method to calculate the scaling potential and the
scale factor. Our method can be applied to any modified gravity model, in
presence of a tachyon field.


title: Largest Laplacian Eigenvalue and Degree Sequences of Trees

abstract:
  We investigate the structure of trees that have greatest maximum eigenvalue
among all trees with a given degree sequence. We show that in such an extremal
tree the degree sequence is non-increasing with respect to an ordering of the
vertices that is obtained by breadth-first search. This structure is uniquely
determined up to isomorphism. We also show that the maximum eigenvalue in such
classes of trees is strictly monotone with respect to majorization.


title:
Rejoinder: Boosting Algorithms: Regularization, Prediction and Model
  Fitting

abstract:
  Rejoinder to ``Boosting Algorithms: Regularization, Prediction and Model
Fitting'' [arXiv:0804.2752]


title: Effects of the quantisation ambiguities on the Big Bounce dynamics

abstract:
  In this paper we investigate dynamics of the modified loop quantum cosmology
models using dynamical systems methods. Modifications considered come from the
choice of the different field strength operator $\hat{F}$ and result in
different forms of the effective Hamiltonian. Such an ambiguity of the choice
of this expression from some class of functions is allowed in the framework of
loop quantisation. Our main goal is to show how such modifications can
influence the bouncing universe scenario in the loop quantum cosmology. In
effective models considered we classify all evolutional paths for all
admissible initial conditions. The dynamics is reduced to the form of a
dynamical system of the Newtonian type on a 2-dimensional phase plane. These
models are equivalent dynamically to the FRW models with the decaying effective
cosmological term parametrised by the canonical variable $p$ (or by the scale
factor $a$). We find that for the positive cosmological constant there is a
class of oscillating models without the initial and final singularities. The
new phenomenon is the appearance of curvature singularities for the finite
values of the scale factor, but we find that for the positive cosmological
constant these singularities can be avoided. For the positive cosmological
constant the evolution begins at the asymptotic state in the past represented
by the deSitter contracting (deS$_{-}$) spacetime or the static Einstein
universe H=0 or $H=-\infty$ state and reaches the deSitter expanding state
(deS$_{+}$), the state H=0 or $H=+\infty$ state. In the case of the negative
cosmological constant we obtain the past and future asymptotic states as the
Einstein static universes.


title: Orbital current patterns in doped two-leg Cu-O Hubbard ladders

abstract:
  In the weak coupling limit, we investigate two-leg ladders with a unit cell
containing both Cu and O atoms, as a function of doping. For purely repulsive
interactions, using bosonization, we find significant differences with the
single orbital case: a completely massless quantum critical regime is obtained
for a finite range of carrier concentration. In a broad region of the phase
diagram the ground state consists of a pattern of orbital currents plus a
density wave. NMR properties of the Cu and O nuclei are presented for the
various phases.


title: Evolution of Low-Mass Helium Stars in Semidetached Binaries

abstract:
  We present results of a systematic investigation of the evolution of low-mass
(0.35, 0.40, and 0.65 solar mass) helium donors in semidetached binaries with
accretors - white dwarfs. In the initial models of evolutionary sequences
abundance of helium in the center is between $\simeq 0.1$ and 0.98. Results of
computations may be applied to the study of the origin and evolutionary state
of AM CVn stars. It is shown that the minimum orbital periods of the systems
only weakly depend on the total mass of the system and evolutionary state of
the donor at RLOF and are equal to 9-11 min. The scatter in the mass-exchange
rates at a given orbital period in the range between period minimum and about
40 min. does not exceed $\sim 2.5$. At orbital periods exceeding about 20 min.
mass-losing stars are weakly degenerate homogeneous cooling objects and
abundances of He, C, N, O, Ne in the matter lost by them depend on the extent
of He-depletion at RLOF. For the systems which are currently considered as the
most probable model candidates for AM CVn stars with helium donors these
abundances are, approximately, Y$>$0.4, X_C$<$0.3, X_O$<$0.25, X_N$<$0.005. At
orbital periods greater than about 40 min. the timescale of mass-loss begins to
exceed thermal time-scale of the donors, the latter begin to contract, they
become more degenerate and, apparently, "white-dwarf" and "helium-star"
populations of AM CVn stars merge.


title:
Electronic and magnetic properties of a quasi-one-dimensional spin chain
  system, Sr$_{3}$NiRhO$_{6}$

abstract:
  We investigate the electronic structure of Sr$_3$NiRhO$_6$, a
quasi-one-dimensional spin chain system using \emph{ab initio} band structure
calculations. Spin polarized calculations within GGA reveal that Ni and Rh have
finite moments and they are antiferromagnetically coupled along the chain axis
in the ground state. While these results obtained within the local spin density
approximations provide remarkable representation of the magnetic phase, the
experimentally observed insulating behavior could not be captured within this
method. GGA+$U$ calculations show that opening up of an insulating gap requires
on-site Coulomb interaction among the Rh 4$d$ electrons, $U_{dd}^{Rh}$
$\approx$ 2.5 eV and the correlation among Ni 3$d$ electrons, $U_{dd}^{Ni}$
$\approx$ 4.5 eV suggesting this system to be a Mott insulator. Electron
correlation among $d$ electrons leads to significant enhancement of the O 2$p$
character in the energy bands in the vicinity of the Fermi level and the $d$
bands appear at lower energies. Energy gap in the up spin density of states
appears to be significantly small ($\sim$ 0.12 eV) while it is $>$ 2 eV in the
down spin density of states suggesting possibility of spin polarized conduction
in the semiconducting phase.


title: Folding and unfolding kinetics of a single semiflexible polymer

abstract:
  We theoretically investigate the kinetics of the folding transition of a
single semiflexible polymer. In the folding transition, the growth rate
decrease with an increase in the number of monomers in a collapsed domain,
suggesting that the main contribution to dissipation is from the motion of the
domain. In the unfolding transition, dynamic scaling exponents, 1/8 and 1/4,
were determined for disentanglement and relaxation steps, respectively. We
performed Langevin dynamics simulations to test our theory. It is found that
our theory is in good agreement with simulations. We also propose the kinetics
of the transitions in the presence of the hydrodynamic interaction.


title: Mergers of Stellar-Mass Black Holes in Nuclear Star Clusters

abstract:
  Mergers between stellar-mass black holes will be key sources of gravitational
radiation for ground-based detectors. However, the rates of these events are
highly uncertain, given that such systems are invisible. One formation scenario
involves mergers in field binaries, where our lack of complete understanding of
common envelopes and the distribution of supernova kicks has led to rate
estimates that range over a factor of several hundred. A different, and highly
promising, channel involves multiple encounters of binaries in globular
clusters or young star clusters. However, we currently lack solid evidence for
black holes in almost all such clusters, and their low escape speeds raise the
possibility that most are ejected because of supernova recoil. Here we propose
that a robust environment for mergers could be the nuclear star clusters found
in the centers of small galaxies. These clusters have millions of stars, black
hole relaxation times well under a Hubble time, and escape speeds that are
several times those of globulars, hence they retain most of their black holes.
We present simulations of the three-body dynamics of black holes in this
environment and estimate that, if most nuclear star clusters do not have
supermassive black holes that interfere with the mergers, at least several tens
of events per year will be detectable with Advanced LIGO.


title:
Reductions of locally conformal symplectic structures and de Rham
  cohomology tangent to a foliation

abstract:
  We propose a produre of reduction a locally conformal symplectic structure.
This procedure of reduction can be applied to wide class of submanifolds. There
are no local obstructions for this procedure. But there are global
obstructions. We find a necessary and sufficient condition when this reduction
holds in terms of the special kind of de Rham cohomology class (tangent to the
characteristic foliation) of the Lee form.


title:
On certain nonlinear elliptic PDE and quasiconfomal mapps between
  Euclidean surfaces

abstract:
  We mainly investigate some properties of quasiconformal mappings between
smooth 2-dimensional surfaces with boundary in the Euclidean space, satisfying
certain partial differential equations (inequalities) concerning Laplacian, and
in particular satisfying Laplace equation and show that that these mappings are
Lipschitz. Conformal parametrization of such surfaces and the method developed
in our paper \cite{km} have important role in this paper.dan curves and is
extended to the case of $C^{2,\alpha}$ surfaces with smooth and compact
boundary.


title: Quantum Interference Effects in Slowly Rotating NUT Space-time

abstract:
  General relativistic quantum interference effects in the slowly rotating NUT
space-time as the Sagnac effect and the phase shift effect of interfering
particle in neutron interferometer are considered. It was found that in the
case of the Sagnac effect the influence of NUT parameter is becoming important
due to the fact that the angular velocity of the locally non rotating observer
must be larger than one in the Kerr space-time. In the case of neutron
interferometry it is found that due to the presence of NUT-parameter an
additional term in the phase shift of interfering particle emerges. This term
can be, in principle, detected by sensitive interferometer and derived results
can be further used in experiments to detect the gravitomagnetic charge.
Finally, as an example, we apply the obtained results to the calculation of the
UCN (ultra-cold neutrons) energy level modification in the slowly rotating NUT
space-time.


title:
Observations of IntraDay Variable sources with the Effelsberg and Urumqi
  Radio Telescopes

abstract:
  A sample of classical IntraDay Variable (IDV) and IDV candidate sources has
been monitored with the Urumqi 25m telescope and the Effelsberg 100m telescope.
Aim of the project is to investigate the origin of IntraDay Variability, a
phenomenon which has been observed in about 30% of flat spectrum radio quasars.
Simultaneous Effelsberg-Urumqi observations demonstrated that the Urumqi
antenna, although relatively small in diameter, is well suitable for IDV
experiments. A few Urumqi datasets, however, turned out to be affected by a
spurious $\sim 24$ hours modulation, an effect which has been removed by means
of a new procedure for data reduction. In about 14 months, 12 epochs of
observation have been collected, for a total observing time of more than 45
days. The epochs are regularly distributed over the whole year, in order to
check for the presence of systematic annual changes in the variability time
scales - a crucial test for verifying the consistency of source-extrinsic
models of the variability. Preliminary time-analysis of the monitored sources
revealed some hint for a slowing down of the characteristic time scales of
S5~0716+714, a result that, if confirmed, would be compatible with a
source-extrinsic origin of the variability, in contrast to previous IDV
studies. No significant modulation of the time scales has been detected for
S4~0954+658.


title:
Universal dependence on disorder of 2D randomly diluted and random-bond
  +-J Ising models

abstract:
  We consider the two-dimensional randomly site diluted Ising model and the
random-bond +-J Ising model (also called Edwards-Anderson model), and study
their critical behavior at the paramagnetic-ferromagnetic transition. The
critical behavior of thermodynamic quantities can be derived from a set of
renormalization-group equations, in which disorder is a marginally irrelevant
perturbation at the two-dimensional Ising fixed point. We discuss their
solutions, focusing in particular on the universality of the logarithmic
corrections arising from the presence of disorder. Then, we present a
finite-size scaling analysis of high-statistics Monte Carlo simulations. The
numerical results confirm the renormalization-group predictions, and in
particular the universality of the logarithmic corrections to the Ising
behavior due to quenched dilution.


title: Kinetic Energy Approach to Dissolving Axisymmetric Multiphase Plumes

abstract:
  A phenomenological kinetic energy theory of buoyant multiphase plumes is
constructed, being general enough to incorporate the dissolution of the
dispersive phase. We consider an axisymmetric plume, and model the dissolution
by means of the Ranz-Marshall equation in which there occurs a mass transfer
coefficient dependent on the plume properties. Our kinetic energy approach is
moreover generalized so as to take into account variable slip velocities.
  The theoretical model is compared with various experiments, and satisfactory
agreement is found. One central ingredient in the model is the turbulent
correlation parameter, called I, playing a role analogous to the conventional
entrainment coefficient \alpha in the more traditional plume theories. We use
experimental data to suggest a relationship between I, the initial gas flux at
the source, and the depth of the gas release. This relationship is used to make
predictions for five distinct case studies.
  Comparison with various experimental data shows that the kinetic energy
approach built upon use of the parameter I in practice has the order of
predictive power as the conventional entrainment-coefficient models. Moreover,
an advantage of the present model is that its predictions are very quickly
worked out numerically.
  Finally, we give a sensitivity analysis of the kinetic energy approach. It
turns out that the model is relatively stable with respect to most of the input
parameters. It is shown that the dissolution is of little influence on the
dynamics of the dispersed phase as long as the dissolution is moderate.


abstract:
  It is revisited the Michelson-Morley experiment within the quantum mechanics
framework. One can define the wave function of photon in the whole space at a
given moment of time. The phase difference between the source and receiver is a
distance between the source and receiver at the time of reception hence it does
not depend on the velocity of the frame. Then one can explain the null result
of the Michelson-Morley experiment within the quantum mechanics framework.


title:
Topological Hochschild and cyclic homology for Differential graded
  categories

abstract:
  We define a topological Hochschild (THH) and cyclic (TC) homology theory for
differential graded (dg) categories and construct several non-trivial natural
transformations from algebraic K-theory to THH(-).
  In an intermediate step, we prove that the homotopy theory of dg categories
is Quillen equivalent, through a four step zig-zag of Quillen equivalences, to
the homotopy theory of Eilenberg-Mac Lane spectral categories.
  Finally, we show that over the rationals two dg categories are topological
equivalent if and only if they are quasi-equivalent.


title:
General solution of a second order non-homogenous linear difference
  equation with noncommutative coefficients

abstract:
  The detailed construction of the general solution of a second order
non-homogenous linear operatordifference equation is presented. The wide
applicability of such an equation as well as the usefulness of its resolutive
formula is shown by studying some applications belonging to different
mathematical contexts.


title: Precise Radial Velocities of Polaris: Detection of Amplitude Growth

abstract:
  We present a first results from a long-term program of a radial velocity
study of Cepheid Polaris (F7 Ib) aimed to find amplitude and period of
pulsations and nature of secondary periodicities. 264 new precise radial
velocity measurements were obtained during 2004-2007 with the fiber-fed echelle
spectrograph Bohyunsan Observatory Echelle Spectrograph (BOES) of 1.8m
telescope at Bohyunsan Optical Astronomy Observatory (BOAO) in Korea. We find a
pulsational radial velocity amplitude and period of Polaris for three seasons
of 2005.183, 2006.360, and 2007.349 as 2K = 2.210 +/- 0.048 km/s, 2K = 2.080
+/- 0.042 km/s, and 2K = 2.406 +/- 0.018 km/s respectively, indicating that the
pulsational amplitudes of Polaris that had decayed during the last century is
now increasing rapidly. The pulsational period was found to be increasing too.
This is the first detection of a historical turnaround of pulsational amplitude
change in Cepheids. We clearly find the presence of additional radial velocity
variations on a time scale of about 119 days and an amplitude of about +/- 138
m/s, that is quasi-periodic rather than strictly periodic. We do not confirm
the presence in our data the variation on a time scale 34-45 days found in
earlier radial velocity data obtained in 80's and 90's. We assume that both the
119 day quasi-periodic, noncoherent variations found in our data as well as
34-45 day variations found before can be caused by the 119 day rotation periods
of Polaris and by surface inhomogeneities such as single or multiple spot
configuration varying with the time.


title:
On three-parametric Lie groups as quasi-Kaehler manifolds with Killing
  Norden metric

abstract:
  A 3-parametric family of 6-dimensional quasi-Kaehler manifolds with Norden
metric is constructed on a Lie group. This family is characterized
geometrically. The condition for such a 6-manifold to be isotropic Kaehler is
given.


title:
Existence and behavior of asymmetric traveling wave solutions to thin
  film equation

abstract:
  We proved the existence and uniqueness of a traveling wave solution to the
thin film equation with a Navier slip condition at the liquid-solid interface.
We obtain explicit lower and upper bounds for the solution and an absolute
error estimate of approximation of a solution to the thin films equation by the
traveling-wave solution.


title:
Phonon and crystal field excitations in geometrically frustrated rare
  earth titanates

abstract:
  The phonon and crystal field excitations in several rare earth titanate
pyrochlores are investigated. Magnetic measurements on single crystals of
Gd2Ti2O7, Tb2Ti2O7, Dy2Ti2O7 and Ho2Ti2O7 are used for characterization, while
Raman spectroscopy and terahertz time domain spectroscopy are employed to probe
the excitations of the materials. The lattice excitations are found to be
analogous across the compounds over the whole temperature range investigated
(295-4 K). The resulting full phononic characterization of the R2Ti2O7
pyrochlore structure is then used to identify crystal field excitations
observed in the materials. Several crystal field excitations have been observed
in Tb2Ti2O7 in Raman spectroscopy for the first time, among which all of the
previously reported excitations. The presence of additional crystal field
excitations, however, suggests the presence of two inequivalent Tb3+ sites in
the low temperature structure. Furthermore, the crystal field level at
approximately 13 cm-1 is found to be both Raman and dipole active, indicating
broken inversion symmetry in the system and thus undermining its current
symmetry interpretation. In addition, evidence is found for a significant
crystal field-phonon coupling in Tb2Ti2O7. These findings call for a careful
reassessment of the low temperature structure of Tb2Ti2O7, which may serve to
improve its theoretical understanding.


title: Quasi-Kaehler manifolds with a pair of Norden metrics

abstract:
  The basic class of the non-integrable almost complex manifolds with a pair of
Norden metrics are considered. The interconnections between corresponding
quantities at the transformation between the two Levi-Civita connections are
given. A 4-parametric family of 4-dimensional quasi-Kaehler manifolds with
Norden metric is characterized with respect to the associated Levi-Civita
connection.


title: Bivariate phase-rectified signal averaging

abstract:
  Phase-Rectified Signal Averaging (PRSA) was shown to be a powerful tool for
the study of quasi-periodic oscillations and nonlinear effects in
non-stationary signals. Here we present a bivariate PRSA technique for the
study of the inter-relationship between two simultaneous data recordings. Its
performance is compared with traditional cross-correlation analysis, which,
however, does not work well for non-stationary data and cannot distinguish the
coupling directions in complex nonlinear situations. We show that bivariate
PRSA allows the analysis of events in one signal at times where the other
signal is in a certain phase or state; it is stable in the presence of noise
and impassible to non-stationarities.


title:
Measurement of the polarization of the $\Upsilon(1S)$ and $\Upsilon(2S)$
  states in $p\bar{p}$ collisions at $\sqrt{s}=$1.96 TeV

abstract:
  We present a study of the polarization of the $\Upsilon(1S)$ and
$\Upsilon(2S)$ states using a $1.3 $ fb$^{-1}$ data sample collected by the D0
experiment in 2002--2006 during Run II of the Fermilab Tevatron Collider. We
measure the polarization parameter
$\alpha=(\sigma_{T}-2\sigma_{L})/(\sigma_{T}+2\sigma_{L})$, where $\sigma_{T}$
and $\sigma_{L}$ are the transversely and longitudinally polarized components
of the production cross section, as a function of the transverse momentum
($p_{T}^{\Upsilon}$) for the $\Upsilon(1S)$ and $\Upsilon(2S)$. Significant
$p_{T}^{\Upsilon}$-dependent longitudinal polarization is observed for the
$\Upsilon(1S)$. A comparison with theoretical models is presented.


title:
Updated predictions for the total production cross sections of top and
  of heavier quark pairs at the Tevatron and at the LHC

abstract:
  We present updated predictions for the total production cross section of
top-quark pairs at the Tevatron and at the LHC, and, at the LHC, of heavy-quark
pairs with mass in the range 0.5-2 TeV. For t\bar{t} production at the LHC we
also present results at \sqrt{S}= 10 TeV, in view of the expected accelerator
conditions during the forthcoming 2008 run. Our results are accurate at the
level of next-to-leading order in alpha_s, and of next-to-leading threshold
logarithms (NLO+NLL). We adopt the most recent parametrizations of parton
distribution functions, and compute the corresponding uncertainties. We study
the dependence of the results on the top mass, and we assess the impact of
missing higher-order corrections by independent variations of factorisation and
renormalisation scales.


title: A Lie group as a 4-dimensional quasi-Kaehler manifold with Norden metric

abstract:
  A 4-parametric family of 4-dimensional quasi-Kaehler manifolds with Norden
metric is constructed on a Lie group. This family is characterized
geometrically. The condition for such a 4-manifold to be isotropic Kaehler is
given.


title: Constraints on nuclear gluon densities from J/psi data

abstract:
  The gluon density in nuclei, G^A(x), is poorly constrained at all x from the
current DIS and Drell-Yan data. In this paper, we point out that J/psi
production measured in proton-nucleus collisions at sqrt(s)=38.8 GeV by the
E866 collaboration puts stringent constraints on the x-dependence of the
G^W/G^Be ratio in the x=0.02-0.1 range. The E866 data suggest a rather mild
x-dependence of G^W/G^Be, and consequently tend to favour DS and HKM sets,
rather than the DSg, EKS, and EPS parametrizations which exhibit a large
shadowing and anti-shadowing.


title: Short and canonical GRBs

abstract:
  Within the "fireshell" model for the Gamma-Ray Bursts (GRBs) we define a
"canonical GRB" light curve with two sharply different components: the
Proper-GRB (P-GRB), emitted when the optically thick fireshell of
electron-positron plasma originating the phenomenon reaches transparency, and
the afterglow, emitted due to the collision between the remaining optically
thin fireshell and the CircumBurst Medium (CBM). We outline our "canonical GRB"
scenario, with a special emphasis on the discrimination between "genuine" and
"fake" short GRBs.


title: On the geometry of quasi-Kaehler manifolds with Norden metric

abstract:
  The basic class of the non-integrable almost complex manifolds with Norden
metric is considered. Its curvature properties are studied. The isotropic
Kaehler type of investigated manifolds is introduced and characterized
geometrically.


title:
Mixing effectiveness depends on the source-sink structure: Simulation
  results

abstract:
  The mixing effectiveness, i.e., the enhancement of molecular diffusion, of a
flow can be quantified in terms of the suppression of concentration variance of
a passive scalar sustained by steady sources and sinks. The mixing enhancement
defined this way is the ratio of the RMS fluctuations of the scalar mixed by
molecular diffusion alone to the (statistically steady-state) RMS fluctuations
of the scalar density in the presence of stirring. This measure of the
effectiveness of the stirring is naturally related to the enhancement factor of
the equivalent eddy diffusivity over molecular diffusion, and depends on the
Peclet number. It was recently noted that the maximum possible mixing
enhancement at a given Peclet number depends as well on the structure of the
sources and sinks. That is, the mixing efficiency, the effective diffusivity,
or the eddy diffusion of a flow generally depends on the sources and sinks of
whatever is being stirred. Here we present the results of particle-based
simulations quantitatively confirming the source-sink dependence of the mixing
enhancement as a function of Peclet number for a model flow.


title:
Conductivity behavior of La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ in vicinity of
  ferromagnetic-paramagnetic transition studied with single current pulses

abstract:
  Temperature and current dependences of resistivity of bulk
La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ sample grown by the floating-zone method were
studied using single ramp pulses of current. It is found that near the Curie
temperature $T_C$ the sample resistance depends substantially on current
magnitude. The observed features can be determined by inhomogeneous Joule
overheating due to mixed phase state of manganites near the
ferromagnetic-paramagnetic transition and percolation character of this
transition.


title: GRBs and the thermalization process of electron-positron plasmas

abstract:
  We discuss the temporal evolution of the pair plasma created in Gamma-Ray
Burst sources. A particular attention is paid to the relaxation of the plasma
into thermal equilibrium. We also discuss the connection between the dynamics
of expansion and the spatial geometry of the plasma. The role of the baryonic
loading parameter is emphasized.


title: Robust Precoder for Multiuser MISO Downlink with SINR Constraints

abstract:
  In this paper, we consider linear precoding with SINR constraints for the
downlink of a multiuser MISO (multiple-input single-output) communication
system in the presence of imperfect channel state information (CSI). The base
station is equipped with multiple transmit antennas and each user terminal is
equipped with a single receive antenna. We propose a robust design of linear
precoder which transmits minimum power to provide the required SINR at the user
terminals when the true channel state lies in a region of a given size around
the channel state available at the transmitter. We show that this design
problem can be formulated as a Second Order Cone Program (SOCP) which can be
solved efficiently. We compare the performance of the proposed design with some
of the robust designs reported in the literature. Simulation results show that
the proposed robust design provides better performance with reduced complexity.


title:
Tangent Bundles with Sasaki Metric and Almost Hypercomplex
  Pseudo-Hermitian Structure

abstract:
  The tangent bundle as a $4n$-manifold is equipped with an almost hypercomplex
pseudo-Hermitian structure and it is characterized with respect to the relevant
classifications. A number of 8-dimensional examples of the considered type of
manifold are received from the known explicit examples in that manner.


title: The decay of magnetohydrodynamic turbulence in a confined domain

abstract:
  The effect of non periodic boundary conditions on decaying two-dimensional
magnetohydrodynamic turbulence is investigated. We consider a circular domain
with no-slip boundary conditions for the velocity and where the normal
component of the magnetic field vanishes at the wall. Different flow regimes
are obtained by starting from random initial velocity and magnetic fields with
varying integral quantities. These regimes, equivalent to the ones observed by
Ting, Matthaeus and Montgomery [Phys. Fluids {\bf 29}, 3261, (1986)] in
periodic domains, are found to subsist in confined domains. We examine the
effect of solid boundaries on the energy decay and alignment properties. The
final states are characterized by functional relationships between velocity and
magnetic field.


title: Spin Foam Perturbation Theory for Three-Dimensional Quantum Gravity

abstract:
  We formulate the spin foam perturbation theory for three-dimensional
Euclidean Quantum Gravity with a cosmological constant. We analyse the
perturbative expansion of the partition function in the dilute-gas limit and we
argue that the Baez conjecture stating that the number of possible distinct
topological classes of perturbative configurations is finite for the set of all
triangulations of a manifold, is not true. However, the conjecture is true for
a special class of triangulations which are based on subdivisions of certain
3-manifold cubulations. In this case we calculate the partition function and
show that the dilute-gas correction vanishes for the simplest choice of the
volume operator. By slightly modifying the dilute-gas limit, we obtain a
nonvanishing correction which is related to the second order perturbative
correction. By assuming that the dilute-gas limit coupling constant is a
function of the cosmological constant, we obtain a value for the partition
function which is independent of the choice of the volume operator.


title: Cyclic Cohomology of the Weyl Algebra

abstract:
  We give an explicit formula for symplectically basic representatives of the
cyclic cohomology of the Weyl algebra. This paper can be seen as cyclic
addendum to the paper by Feigin, Felder and Shoikhet, where the analogous
Hochschild case was treated.
  As an application, we prove a generalization of a Theorem of Nest and Tsygan
concerning the relation of the Todd class and the cyclic cohomology of the
differential operators on a complex manifold.


title: Noncommutative space and the low-energy physics of quasicrystals

abstract:
  We prove that the effective low-energy, nonlinear Schroedinger equation for a
particle in the presence of a quasiperiodic potential is the potential-free,
nonlinear Schroedinger equation on noncommutative space. Thus quasiperiodicity
of the potential can be traded for space noncommutativity when describing the
envelope wave of the initial quasiperiodic wave.


title: Some four-dimensional almost hypercomplex pseudo-Hermitian manifolds

abstract:
  In this paper, a lot of examples of four-dimensional manifolds with an almost
hypercomplex pseudo-Hermitian structure are constructed in several explicit
ways. The received 4-manifolds are characterized by their linear invariants in
the known aspects.


title: Impact of early dark energy on the Planck SZ cluster sample

abstract:
  Context. One science goal of the upcoming Planck mission is to perform a
full-sky cluster survey based on the Sunyaev-Zel'dovich (SZ) effect, which
leads to the question of how such a survey would be affected by cosmological
models with a different history of structure formation than LCDM. One class of
these models are early dark energy (EDE) cosmologies, where the dark energy
contribution does not vanish at early times.
  Aims. Since structures grow slower in the presence of EDE, one expects an
increase in the number of galaxy clusters compared to LCDM at intermediate and
high redshifts, which could explain the reported excess of the angular CMB
power spectrum on cluster scales via an enhanced SZ contribution. We study the
impact of EDE on Planck's expected cluster sample.
  Methods. To obtain realistic simulations, we constructed full-sky SZ maps for
EDE and LCDM cosmologies, taking angular cluster correlation into account.
Using these maps, we simulated Planck observations with and without Galactic
foregrounds and fed the results into our filter pipeline based on the spherical
multi-frequency matched filters.
  Results. For the case of EDE cosmologies, we clearly find an increase in the
detected number of clusters compared to the fiducial LCDM case. This shows that
the spherical multi-frequency matched filter is sensitive enough to find
deviations from the LCDM sample, being caused by EDE. In addition we find an
interesting effect of EDE on the completeness of the cluster sample, such that
EDE helps to obtain cleaner samples.


title: The "Fireshell" model in the Swift era

abstract:
  We here re-examine the validity of the constant-index power-law relation
between the fireshell Lorentz gamma factor and its radial coordinate, usually
adopted in the current Gamma-Ray Burst (GRB) literature on the grounds of an
"ultrarelativistic" approximation. Such expressions are found to be
mathematically correct but only approximately valid in a very limited range of
the physical and astrophysical parameters and in an asymptotic regime which is
reached only for a very short time, if any.


title:
Effective-medium theory for infinite-contrast, 2D-periodic, linear
  composites with strongly anisotropic matrix behavior: dilute limit and
  cross-over behavior

abstract:
  The overall behavior of a 2D lattice of voids embedded in an anisotropic
matrix is investigated in the limit of vanishing porosity f. An
effective-medium model (of the Hashin-Shtrikman type) which accounts for
elastic interactions between neighboring voids, is compared to Fast Fourier
Transform numerical solutions and, in the limits of infinite anisotropy, to
exact results. A cross-over between regular and singular dilute regimes is
found, driven by a characteristic length which depends on f and on the
anisotropy strength. The singular regime, where the leading dilute correction
to the elastic moduli is an O(f^{1/2}), is related to strain localization and
to change in character - from elliptic to hyperbolic - of the governing
equations.


title: Theoretical interpretation of "long" and "short" GRBs

abstract:
  Within the "fireshell" model we define a "canonical GRB" light curve with two
sharply different components: the Proper-GRB (P-GRB), emitted when the
optically thick fireshell of electron-positron plasma originating the
phenomenon reaches transparency, and the afterglow, emitted due to the
collision between the remaining optically thin fireshell and the CircumBurst
Medium (CBM). We here present the consequences of such a scenario on the
theoretical interpretation of the nature of "long" and "short" GRBs.


title: Bipolarization of posets and natural interpolation

abstract:
  The Choquet integral w.r.t. a capacity can be seen in the finite case as a
parsimonious linear interpolator between vertices of $[0,1]^n$. We take this
basic fact as a starting point to define the Choquet integral in a very general
way, using the geometric realization of lattices and their natural
triangulation, as in the work of Koshevoy. A second aim of the paper is to
define a general mechanism for the bipolarization of ordered structures. Bisets
(or signed sets), as well as bisubmodular functions, bicapacities,
bicooperative games, as well as the Choquet integral defined for them can be
seen as particular instances of this scheme. Lastly, an application to
multicriteria aggregation with multiple reference levels illustrates all the
results presented in the paper.


title:
Signals of CPT Violation and Non-Locality in Future Neutrino Oscillation
  Experiments

abstract:
  We investigate the sensitivities of future neutrino oscillation experiments
for measuring the neutrino mass squared differences and leptonic mixing angles
independently with neutrinos and anti-neutrinos. We update the expected
sensitivities of Neutrino Factories to the "atmospheric" (anti-)neutrino
parameters using an optimized setup. A dedicated beta-Beam facility, in
combination with a SPMIN reactor experiment, could give excellent sensitivities
also to the "solar" parameters, for neutrinos and anti-neutrinos respectively.
A signal of a different mass matrix for neutrinos and anti-neutrinos would
imply CPT violation and non-locality of the underlying particle theory.


title:
Theoretical interpretation of luminosity and spectral properties of GRB
  031203

abstract:
  We show how an emission endowed with an instantaneous thermal spectrum in the
co-moving frame of the expanding fireshell can reproduce the time-integrated
GRB observed non-thermal spectrum. An explicit example in the case of GRB
031203 is presented.


title: Nested Bethe ansatz for "all" closed spin chains

abstract:
  We present in an unified and detailed way the Nested Bethe Ansatz for closed
spin chains based on Y(gl(n)), Y(gl(m|n)), U_q(gl(n)) or U_q(gl(m|n))
(super)algebras, with arbitrary representations (i.e. `spins') on each site of
the chain. In particular, the case of indecomposable representations of
superalgebras is studied. The construction extends and unifies the results
already obtained for spin chains based on Y(gl(n)) or U_q(gl(n)) and for some
particular super-spin chains. We give the Bethe equations and the form of the
Bethe vectors. The case of gl(2|1), gl(2|2$ and gl(4|4) superalgebras (that are
related to AdS/CFT correspondence) is also detailed.


title:
Energy dependence of nucleus-nucleus potential close to the Coulomb
  barrier

abstract:
  The nucleus-nucleus interaction potentials in heavy-ion fusion reactions are
extracted from the microscopic time-dependent Hartree-Fock theory for mass
symmetric reactions $^{16}$O${}+^{16}$O, $^{40}$Ca${}+^{40}$Ca,
$^{48}$Ca${}+^{48}$Ca and mass asymmetric reactions $^{16}$O$ +^{40,48}$Ca,
$^{40}$Ca${}+^{48}$Ca, $^{16}$O+$^{208}$Pb, $^{40}$Ca+$^{90}$Zr. When the
center-of-mass energy is much higher than the Coulomb barrier energy,
potentials deduced with the microscopic theory identify with the frozen density
approximation. As the center-of-mass energy decreases and approaches the
Coulomb barrier, potentials become energy dependent. This dependence signs
dynamical reorganization of internal degrees of freedom and leads to a
reduction of the "apparent" barrier felt by the two nuclei during fusion of the
order of $2-3 %$ compared to the frozen density case. Several examples
illustrate that the potential landscape changes rapidly when the center-of-mass
energy is in the vicinity of the Coulomb barrier energy. The energy dependence
is expected to have a significant role on fusion around the Coulomb barrier.


title: Perturbation theory for bright spinor Bose--Einstein condensate solitons

abstract:
  We develop a perturbation theory for bright solitons of the F=1 integrable
spinor Bose-Einstein condensate (BEC) model. The formalism is based on using
the Riemann-Hilbert problem and provides the means to analytically calculate
evolution of the soliton parameters. Both rank-one and rank-two soliton
solutions of the model are obtained. We prove equivalence of the rank-one
soliton and the ferromagnetic rank-two soliton. Taking into account a splitting
of a perturbed polar rank-two soliton into two ferromagnetic solitons, it is
sufficient to elaborate a perturbation theory for the rank-one solitons only.
  Treating a small deviation from the integrability condition as a
perturbation, we describe the spinor BEC soliton dynamics in the adiabatic
approximation. It is shown that the soliton is quite robust against such a
perturbation and preserves its velocity, amplitude, and population of different
spin components, only the soliton frequency acquires a small shift. Results of
numerical simulations agree well with the analytical predictions, demonstrating
only slight soliton profile deformation.


title: Large-Scale Thermal Convection in a Horizontal Porous Layer

abstract:
  In a range of physical systems, the first instability in Rayleigh-Bernard
convection between nearly thermally insulating horizontal plates is large
scale. This holds for thermal convection of fluids saturating porous media.
Large-scale thermal convection in a horizontal layer is governed by remarkably
similar equations both in the presence of a porous matrix and without it, with
only one additional term for the latter case, which, however, vanishes under
certain conditions (e.g., two-dimensional flows or infinite Prandtl number). We
provide a rigorous derivation of long-wavelength equations for a porous layer
with inhomogeneous heating and possible pumping.


title: Three-fluid plasmas in star formation I. Magneto-hydrodynamic equations

abstract:
  Interstellar magnetic fields influence all stages of the process of star
formation, from the collapse of molecular cloud cores to the formation of
protostellar jets. This requires us to have a full understanding of the
physical properties of magnetized plasmas of different degrees of ionization
for a wide range of densities and temperatures. We derive general equations
governing the magneto-hydrodynamic evolution of a three-fluid medium of
arbitrary ionization, also including the possibility of charged dust grains as
the main charge carriers. In a companion paper (Pinto & Galli 2007), we
complement this analysis computing accurate expressions of the collisional
coupling coefficients. Over spatial and temporal scales larger than the
so-called large-scale plasma limit and the collision-dominated plasma limit,
and for non-relativistic fluid speeds, we obtain an advection-diffusion for the
magnetic field. We derive the general expressions for the resistivities, the
diffusion time scales and the heating rates in a three-fluid medium and we use
them to estimate the evolution of the magnetic field in molecular clouds and
protostellar jets. Collisions between charged particles significantly increase
the value of the Ohmic resistivity during the process of cloud collapse,
affecting in particular the decoupling of matter and magnetic field and
enhancing the rate of energy dissipation. The Hall resistivity can take larger
values than previously found when the negative charge is mostly carried by dust
grains. In weakly-or mildy-ionized protostellar jets, ambipolar diffusion is
found to occur on a time scale comparable to the dynamical time scale, limiting
the validity of steady-state and nondissipative models to study the jet's
structure.


title:
Dissecting the Gravitational Lens B1608+656. I. Lens Potential
  Reconstruction

abstract:
  Strong gravitational lensing is a powerful technique for probing galaxy mass
distributions and for measuring cosmological parameters. We present a pixelated
approach to modeling simultaneously the lens potential and source intensity of
strong gravitational lens systems with extended source-intensity distributions.
For systems with sources of sufficient extent such that the separate lensed
images are connected by intensity measurements, the accuracy in the
reconstructed potential is solely limited by the quality of the data. We apply
this potential reconstruction technique to deep HST observations of B1608+656,
a four-image gravitational lens system formed by a pair of interacting lens
galaxies. We present a comprehensive Bayesian analysis of the system that takes
into account the extended source-intensity distribution, dust extinction, and
the interacting lens galaxies. Our approach allows us to compare various models
of the components of the lens system, which include the point-spread function
(PSF), dust, lens galaxy light, source-intensity distribution, and lens
potential. Using optimal combinations of the PSF, dust, and lens galaxy light
models, we successfully reconstruct both the lens potential and the extended
source-intensity distribution of B1608+656. The resulting reconstruction can be
used as the basis of a measurement of the Hubble constant. We use our
reconstruction of the gravitational potential to study the relative
distribution of mass and light in the lensing galaxies. We find that the
mass-to-light ratio for the primary lens galaxy is (2.0+/-0.2)h M_{\sun}
L_{B,\sun}^{-1} within the Einstein radius 3.9 h^{-1} kpc, in agreement with
what is found for noninteracting lens galaxies at the same scales. (Abridged)


title:
On the equivariant and the non-equivariant main conjecture for imaginary
  quadratic fields

abstract:
  The Iwasawa main conjecture fields has been an important tool to study the
arithmetic of special values of $L$-functions of Hecke characters of imaginary
quadratic fields. To obtain the finest possible invariants it is important to
know the main conjecture for all prime numbers $p$ and also to have an
equivariant version at disposal.
  In this paper we first prove the main conjecture for imaginary quadratic
fields for all prime numbers $p$, improving earlier results by Rubin. From this
we deduce the equivariant main conjecture in the case that a certain
$\mu$-invariant vanishes. For prime numbers $p\nmid 6$ which split in $K$, this
is a theorem by a result of Gillard.


title: Spin Effects for Neutrinos and Electrons Moving in Dense Matter

abstract:
  We shortly summarize the present status of neutrino magnetic moment studies
(theory and experiment). Then we discuss the quasiclassical treatment of
neutrino spin evolution in matter. After that we come to the quantum approach
to description of neutrino and electron motion in matter on the basis of the
quantum wave equations exact solutions method with special focus on spin
effects.


title: Extraordinary sound screening in perforated plates

abstract:
  We report extraordinary effects in the transmission of sound through
periodically perforated plates, supported by both measurements and theory. In
agreement with recent observations in slit arrays [M. H. Lu et al. Phys. Rev.
Lett. 99, 174301 (2007)], nearly full transmission is observed at certain
resonant frequencies, pointing out at similarities of the acoustic phenomena
and their optical counterpart. However, acoustic screening well beyond that
predicted by the mass law is achieved over a wide range of wavelengths in the
vicinity of the period of the array, resulting in fundamentally unique behavior
of the sound as compared to light. The randomness of the hole distribution and
the impedance contrast between the fluid and the solid plate are found to play
a crucial role.


title:
Decentralized Knowledge and Learning in Strategic Multi-user
  Communication

abstract: Please see the content of this report.


title: Uniform lamda-adjustment and mu-approximation in Banach spaces

abstract:
  We introduce a new concept of perturbation of closed linear subspaces and
operators in Banach spaces called uniform lambda-adjustment which is weaker
than perturbations by small gap, operator norm, q-norm, and K2-approximation.
In arbitrary Banach spaces some of the classical Fredholm stability theorems
remain true under uniform lambda-adjustment, while other fail. However,
uniformly lambda-adjusted subspaces and linear operators retain their
(semi--)Fredholm properties in a Banach space which dual is Fr\'{e}chet-Urysohn
in weak* topology. We also introduce another concept of perturbation called
uniform mu-approximation which is weaker than perturbations by small gap, norm,
and compact convergence, yet stronger than uniform lambda-adjustment. We
present Fredholm stability theorems for uniform mu-approximation in arbitrary
Banach spaces and a theorem on stability of Riesz kernels and ranges for
commuting closed essentially Kato operators. Finally, we define the new
concepts of a tuple of subspaces and of a complex of subspaces in Banach
spaces, and present stability theorems for index and defect numbers of Fredholm
tuples and complexes under uniform lambda-adjustment and uniform
mu-approximation.


title: Inequalities of Hardy-Sobolev type in Carnot-Carath\'eodory spaces

abstract:
  We consider various types of Hardy-Sobolev inequalities on a
Carnot-Carath\'eodory space $(\Om, d)$ associated to a system of smooth vector
fields $X=\{X_1, X_2,...,X_m\}$ on $\RR^n$ satisfying the H\"ormander's finite
rank condition $rank Lie[X_1,...,X_m] \equiv n$. One of our main concerns is
the trace inequality
  \int_{\Om}|\phi(x)|^{p}V(x)dx\leq C\int_{\Om}|X\phi|^{p}dx,\qquad \phi\in
C^{\infty}_{0}(\Om),
  where $V$ is a general weight, i.e., a nonnegative locally integrable
function on $\Om$, and $1<p<+\infty$. Under sharp geometric assumptions on the
domain $\Om\subset \Rn$ that can be measured equivalently in terms of
subelliptic capacities or Hausdorff contents, we establish various forms of
Hardy-Sobolev type inequalities.


title: Non-$\mathbb{Z}_{2}$ symmetric braneworlds in scalar tensorial gravity

abstract:
  We obtain, via the Gauss-Codazzi formalism, the expression of the effective
Einstein-Brans-Dicke projected equations in a non-$\mathbb{Z}_{2}$ symmetric
braneworld scenario which presents hybrid compactification. It is shown that
the functional form of such equations resembles the one in the Einstein's case,
except by the fact that they bring extra informations in the context of exotic
compactifications.


title: Nereid: Light Curve for 1999-2006 and a Scenario for its Variations

abstract:
  Nereid is a small irregular moon of Neptune that displays large-, moderate-,
and small-amplitude photometric variations on both fast and slow time scales.
The central mystery of Nereid is now to explain the physical mechanism of these
unique brightness changes and why they change with time. To characterize
Nereid's variability, we have been using the SMARTS telescopes on Cerro Tololo
for synoptic monitoring from 1999 to 2006. We present a well-sampled
photometric time series of 493 magnitudes on 246 nights mostly in the V-band.
In combination with our earlier data (for 774 magnitudes over 362 nights), our
20-year data set is the most comprehensive for any small icy body in our Solar
System. Our yearly light curves show that Nereid displays various types of
behaviors: large amplitude brightenings and fadings (1987 to 1990);
moderate-amplitude variation about the average phase curve (1993-1997, 2003,
2005), moderate-amplitude variation and systematically brighter by roughly
one-quarter magnitude throughout the entire season (2004); and nearly constant
light curves superimposed on a surprisingly large-amplitude opposition surge
(1998, 1999, 2000, 2006). Other than in 2004, Nereid's variations were closely
centered around a constant phase curve that is well fit with a Hapke model for
the coherent backscattering opposition surge mechanism with angular scale of
0.7+-0.1 degrees. In our entire data set from 1987-2006, we find no significant
periodicity. We propose that the year-to-year changes in the variability of
Nereid are caused by forced precession (caused by tidal forces from Neptune) on
the spin axis of a nonspherical Nereid, such that cross-sectional areas and
average albedos change as viewed from Earth.


abstract:
  We present two new forms in which the Frechet differential of a power series
in a Banach algebra can be expressed in terms of absolutely convergent series
involving the commutant $C(T):A\mapsto [A,T]$.Then we apply the results to the
analytic functional calculus in a complex Banach space.


title: On Gamma-Ray Bursts

abstract:
  (Shortened) We show by example how the uncoding of Gamma-Ray Bursts (GRBs)
offers unprecedented possibilities to foster new knowledge in fundamental
physics and in astrophysics. After recalling some of the classic work on vacuum
polarization in uniform electric fields by Klein, Sauter, Heisenberg, Euler and
Schwinger, we summarize some of the efforts to observe these effects in heavy
ions and high energy ion collisions. We then turn to the theory of vacuum
polarization around a Kerr-Newman black hole, leading to the extraction of the
blackholic energy, to the concept of dyadosphere and dyadotorus, and to the
creation of an electron-positron-photon plasma. We then present a new
theoretical approach encompassing the physics of neutron stars and heavy
nuclei. It is shown that configurations of nuclear matter in bulk with global
charge neutrality can exist on macroscopic scales and with electric fields
close to the critical value near their surfaces. These configurations may
represent an initial condition for the process of gravitational collapse,
leading to the creation of an electron-positron-photon plasma: the basic
self-accelerating system explaining both the energetics and the high energy
Lorentz factor observed in GRBs. We then turn to recall the two basic
interpretational paradigms of our GRB model. [...] We then turn to the special
role of the baryon loading in discriminating between "genuine" short and long
or "fake" short GRBs [...] We finally turn to the GRB-Supernova Time Sequence
(GSTS) paradigm: the concept of induced gravitational collapse. [...] We then
present some general conclusions.


title: Dirac Vs. Majorana Neutrino Masses From a TeV Interval

abstract:
  We investigate the nature (Dirac vs. Majorana) and size of left-handed
neutrino masses in a supersymmetric five-dimensional model compactified in the
interval [0,\pi R], where quarks and leptons are localized on the boundaries
while the gauge and Higgs sectors propagate in the bulk of the fifth dimension.
Supersymmetry is broken by Scherk-Schwarz boundary conditions and electroweak
breaking proceeds through radiative corrections. Right-handed neutrinos
propagate in the bulk and have a general five-dimensional mass M, which
localizes the zero modes towards one of the boundaries, and arbitrary boundary
terms. We have found that for generic boundary terms left-handed neutrinos have
Majorana masses. However for specific boundary configurations left-handed
neutrinos are Dirac fermions as the theory possesses a conserved global U(1)
symmetry which prevents violation of lepton number. The size of neutrino masses
depends on the localization of the zero-modes of right-handed neutrinos and/or
the size of the five-dimensional neutrino Yukawa couplings. Left-handed
neutrinos in the sub-eV range require either MR~10 or Yukawa couplings
~10^{-3}R, which make the five-dimensional theory perturbative up to its
natural cutoff.


title:
From Rindler space to the electromagnetic energy-momentum tensor of a
  Casimir apparatus in a weak gravitational field

abstract:
  This paper studies two perfectly conducting parallel plates in the weak
gravitational field on the surface of the Earth. Since the appropriate line
element, to first order in the constant gravity acceleration g, is precisely of
the Rindler type, we can exploit the formalism for studying Feynman Green
functions in Rindler spacetime. Our analysis does not reduce the
electromagnetic potential to the transverse part before quantization. It is
instead fully covariant and well suited for obtaining all components of the
regularized and renormalized energy-momentum tensor to arbitrary order in the
gravity acceleration g. The general structure of the calculation is therefore
elucidated, and the components of the Maxwell energy-momentum tensor are
evaluated up to second order in g, improving a previous analysis by the authors
and correcting their old first-order formula for the Casimir energy.


title:
Effect of electron-electron scattering on spin dephasing in a
  high-mobility low-density twodimensional electron gas

abstract:
  Utilizing time-resolved Kerr rotation techniques, we have investigated the
spin dynamics of a high mobility, low density two dimensional electron gas in a
GaAs/Al0:35Ga0:65As heterostructure in dependence on temperature from 1.5 K to
30 K. It is found that the spin relaxation/dephasing time under a magnetic
field of 0.5 T exhibits a maximum of 3.12 ns around 14 K, superimposed on an
increasing background with rising temperature. The appearance of the maximum is
ascribed to that at the temperature where the crossover from the degenerate to
the nondegenerate regime takes place, electron-electron Coulomb scattering
becomes strongest, and thus inhomogeneous precession broadening due to
D'yakonov-Perel'(DP) mechanism becomes weakest. These results agree with the
recent theoretical predictions [Zhou et al., PRB 75, 045305 (2007)], verifying
the importance of electron-electron Coulomb scattering to electron spin
relaxation/dephasing.


title: Note on the Cantor-Bendixson rank of limit groups

abstract:
  We show that the Cantor-Bendixson rank of a limit group is finite as well as
that of a limit group of a linear group.


title: Monotonicity of Subelliptic Estimates on Rigid Pseudoconvex Domains

abstract:
  This paper presents monotonicity of subelliptic estimates on rigid
pseudoconvex domains. As an application of monotonicity, we will show that if a
rigid monomial domain is of finite type in the D'Angelo's sense, then the sharp
subelliptic estimate of this domain equals the reciprocal of the type.


title: Relative Riemann-Zariski spaces

abstract:
  In this paper we study relative Riemann-Zariski spaces attached to a morphism
of schemes and generalizing the classical Riemann-Zariski space of a field. We
prove that similarly to the classical RZ spaces, the relative ones can be
described either as projective limits of schemes in the category of locally
ringed spaces or as certain spaces of valuations. We apply these spaces to
prove the following two new results: a strong version of stable modification
theorem for relative curves; a decomposition theorem which asserts that any
separated morphism between quasi-compact and quasi-separated schemes factors as
a composition of an affine morphism and a proper morphism. (In particular, we
obtain a new proof of Nagata's compactification theorem.)


title:
An Analysis of Key Factors for the Success of the Communal Management of
  Knowledge

abstract:
  This paper explores the links between Knowledge Management and new
community-based models of the organization from both a theoretical and an
empirical perspective. From a theoretical standpoint, we look at Communities of
Practice (CoPs) and Knowledge Management (KM) and explore the links between the
two as they relate to the use of information systems to manage knowledge. We
begin by reviewing technologically supported approaches to KM and introduce the
idea of "Systemes d'Aide a la Gestion des Connaissances" SAGC (Systems to aid
the Management of Knowledge). Following this we examine the contribution that
communal structures such as CoPs can make to intraorganizational KM and
highlight some of 'success factors' for this approach to KM that are found in
the literature. From an empirical standpoint, we present the results of a
survey involving the Chief Knowledge Officers (CKOs) of twelve large French
businesses; the objective of this study was to identify the factors that might
influence the success of such approaches. The survey was analysed using
thematic content analysis and the results are presented here with some short
illustrative quotes from the CKOs. Finally, the paper concludes with some brief
reflections on what can be learnt from looking at this problem from these two
perspectives.


title:
Deterministic control of all-optical analogue to electromagnetically
  induced transparency in coherently-coupled silicon photonic crystal cavities

abstract:
  Quantum coherence in atomic systems has led to fascinating outcomes, such as
laser cooling and trapping, Bose-Einstein condensates, and
electromagnetically-induced-transparency (EIT). In EIT, the sharp cancellation
of medium absorption has led to phenomena such as lasing without inversion,
freezing light, and dynamic storage of light in a solid-state system. Similar
to atomic systems, EIT-like effects can be observed through classical and
optical means. Here we report the first experimental deterministic tuning of
all-optical analogue to EIT in coherently-coupled standing-wave photonic
crystal cavities. Our observations include transparency-resonance lifetimes
more than three times the single loaded cavity, Fano-type lineshapes, and
stepwise control of the coherent cavity-cavity interference. Our system, with
wavelength-scale localization and coupled to a single waveguide, is analyzed
well through the coupled-mode formalism which examines the delay in both
transparency- and Fano-like lineshapes. Our observations support applications
towards all-optical trapping, stopping and time-reversal of light in a
solid-state scalable implementation.


title: Chain inflation revisited

abstract:
  This paper represents an in-depth treatment of the chain inflation scenario.
We fully determine the evolution of the universe in the model, the necessary
conditions in order to have a successful inflationary period, and the matching
with the observational results regarding the cosmological perturbations. We
study in great detail, and in general, the dynamics of the background, as well
as the mechanism of generation of the perturbations. We also find an explicit
formula for the spectrum of adiabatic perturbations. Our results prove that
chain inflation is a viable model for solving the horizon, entropy and flatness
problem of standard cosmology and for generating the right amount of adiabatic
cosmological perturbations. The results are radically different from those
found in previous works on the subject. Finally, we argue that there is a
natural way to embed chain inflation into flux compactified string theory. We
discuss the details of the implementation and how to fit observations.


title:
The Concept of Appropriation as a Heuristic for Conceptualising the
  Relationship between Technology, People and Organisations

abstract:
  The stated aim of this conference is to debate the continuing evolution of IS
in businesses and other organisations. This paper seeks to contribute to this
debate by exploring the concept of appropriation from a number of different
epistemological, cultural and linguistic viewpoints to allow us to explore 'the
black box' of appropriation and to gain a fuller understanding of the term. At
the conceptual level, it will examine some of the different ways in which
people have attempted to explain the relationship between the objective and
concrete features of technology and the subjective and shifting nature of the
people and organisation within which that technology is deployed. At the
cultural and linguistic level the paper will examine the notion as it is found
in the Francophone literature, where the term has a long and rich history, and
the Anglophone literature where appropriation is seen as a rather more
specialist term. The paper will conclude with some observations on the ongoing
nature of the debate, the value of reading beyond the literature with which one
is familiar and the rewards that come from exploring different historical (and
linguistic) viewpoints.


title:
Information Preserving Component Analysis: Data Projections for Flow
  Cytometry Analysis

abstract:
  Flow cytometry is often used to characterize the malignant cells in leukemia
and lymphoma patients, traced to the level of the individual cell. Typically,
flow cytometric data analysis is performed through a series of 2-dimensional
projections onto the axes of the data set. Through the years, clinicians have
determined combinations of different fluorescent markers which generate
relatively known expression patterns for specific subtypes of leukemia and
lymphoma -- cancers of the hematopoietic system. By only viewing a series of
2-dimensional projections, the high-dimensional nature of the data is rarely
exploited. In this paper we present a means of determining a low-dimensional
projection which maintains the high-dimensional relationships (i.e.
information) between differing oncological data sets. By using machine learning
techniques, we allow clinicians to visualize data in a low dimension defined by
a linear combination of all of the available markers, rather than just 2 at a
time. This provides an aid in diagnosing similar forms of cancer, as well as a
means for variable selection in exploratory flow cytometric research. We refer
to our method as Information Preserving Component Analysis (IPCA).


title:
Dark Energy, Background Independent Quantum Mechanics and the Origin of
  Cosmological Constant

abstract:
  We explore the extended framework of the generalized quantum mechanics and
discuss various aspects of neighborhood in the construction of space in search
of origin of cosmological constant. We propose to expand definition of the
volume of the phase space in eight dimensions with an overall constraint in the
form of uncertainty relation as: $(\Delta p_{x}\Delta p_{y}\Delta p_{z}\Delta
E)(\Delta x\Delta y\Delta z\Delta t)\sim h^{4}$. We argue that the phase space
volume in the eight dimensions is an appropriate representation that it should
be, and the relation $(\Delta \Lambda)(\Delta V)\sim h$ again brings it down to
the reduced phase space.


title: Cylindrical Superlens by a Coordinate Transformation

abstract:
  Cylinder-shaped perfect lens deduced from the coordinate transformation
method is proposed. The previously reported perfect slab lens is noticed to be
a limiting form of the cylindrical lens when the inner radius approaches
infinity with respect to the lens thickness. Connaturality between a
cylindrical lens and a slab lens is affirmed by comparing their eigenfield
transfer functions. We numerically confirm the subwavelength focusing
capability of such a cylindrical lens with consideration of material
imperfection. Compared to a slab lens, a cylindrical lens has several
advantages, including finiteness in cross-section, and ability in lensing with
magnification or demagnification. Immediate applications of such a cylindrical
lens can be in high-resolution imaging and lithography technologies. In
addition, its invisibility property suggests that it may be valuable for
non-invasive electromagnetic probing.