title: Efficient quantum circuits for one-way quantum computing

abstract:
  While Ising-type interactions are ideal for implementing controlled phase
flip gates in one-way quantum computing, natural interactions between
solid-state qubits are most often described by either the XY or the Heisenberg
models. We show an efficient way of generating cluster states directly using
either the iSWAP gate for the XY model, or the $\sqrt{\rm SWAP}$ gate for the
Heisenberg model. Our approach thus makes one-way quantum computing more
feasible for solid-state devices.


title: Classification of the Entangled States of $2 \times N \times N$

abstract:
  We develop a novel method in classifying the multipartite entanglement state
of $2\times N\times N$ under stochastic local operation and classical
communication. In this method, all inequivalent classes of true entangled state
can be assorted directly without knowing the classification information of
lower dimension ones for any given dimension $N$. It also gives a nature
explanation for the non-local parameters remaining in the entanglement classes
while $N\geq 4$ .


title:
The removal of shear-ellipticity correlations from the cosmic shear
  signal via nulling techniques

abstract:
  To render cosmic shear an astronomical tool of high precision, it is
essential to eliminate systematic effects upon its signal, one of the most
significant ones being correlations between the gravitational shear and the
intrinsic ellipticity of source galaxies. Because of the crudeness of current
models of intrinsic alignment, we have developed a model-independent, purely
geometrical method to remove shear-ellipticity correlations. We eliminate the
contributions to a tomographic cosmic shear signal that may be subject to
contamination by shear-ellipticity correlations, making use of the
characteristic dependence of these correlations on redshift. By introducing an
appropriately chosen weight function to the lensing efficiency that nulls
signals stemming from certain distances, new second-order measures of cosmic
shear, free of intrinsic alignment, can be constructed. The loss of information
induced by this nulling technique and the subsequent degradation of constraints
on cosmological parameters is quantified in a likelihood analysis. Concerning
the construction of optimal weight functions, good agreement is achieved
between all approaches considered. For a survey divided into 20 redshift bins
we find that the area of credible regions increases by 20% up to about 50%
after the application of nulling, depending on the cosmological parameters
considered. We demonstrate that due to an optimization of the weight functions
nearly all information is contained in a small subset of the new second-order
measures. The use of a significantly smaller number of redshift bins than 20
for the nulling considerably degrades parameter constraints under conservative
assumptions, emphasizing the need for detailed redshift information.


title: Red Galaxy Growth and the Halo Occupation Distribution

abstract:
  We have traced the past 7 Gyr of red galaxy stellar mass growth within dark
matter halos. We have determined the halo occupation distribution, which
describes how galaxies reside within dark matter halos, using the observed
luminosity function and clustering of 40,696 0.2<z<1.0 red galaxies in Bootes.
Half of 10^{11.9} Msun/h halos host a red central galaxy, and this fraction
increases with increasing halo mass. We do not observe any evolution of the
relationship between red galaxy stellar mass and host halo mass, although we
expect both galaxy stellar masses and halo masses to evolve over cosmic time.
We find that the stellar mass contained within the red population has doubled
since z=1, with the stellar mass within red satellite galaxies tripling over
this redshift range. In cluster mass halos most of the stellar mass resides
within satellite galaxies and the intra-cluster light, with a minority of the
stellar mass residing within central galaxies. The stellar masses of the most
luminous red central galaxies are proportional to halo mass to the power of a
third. We thus conclude that halo mergers do not always lead to rapid growth of
central galaxies. While very massive halos often double in mass over the past 7
Gyr, the stellar masses of their central galaxies typically grow by only 30%.


title:
Mass transfer from a giant star to a main sequence companion and its
  contribution to long-orbital-period blue stragglers

abstract:
  Binary population synthesis shows that mass transfer from a giant star to a
main-sequence (MS) companion may account for some observed long-orbital period
blue stragglers. However, little attention {\bf is paid to this blue straggler
formation scenario} as dynamical instability often happens when the mass donor
is a giant star. In this paper, we have studied the critical mass ratio,
$q_{\rm c}$, for dynamically stable mass transfer from a giant star to a MS
companion using detailed evolution calculations. The results show that a more
evolved star is generally less stable for Roche lobe overflow. Meanwhile,
$q_{\rm c}$ almost linearly increases with the amount of the mass and angular
momentum {\bf lost} during mass transfer, but has little dependance on stellar
wind. To conveniently use the result, we give a fit of $q_{\rm c}$ as a
function of the stellar radius at the onset of Roche lobe overflow and of the
mass transfer efficiency during the Roche lobe overflow.
  To examine the formation of blue stragglers from mass transfer between giants
and MS stars, we have performed Monte Carlo simulations with various $q_{\rm
c}$. {\bf The simulations show that some binaries with the mass donor on the
first giant branch may contribute to blue stragglers with $q_{\rm c}$ obtained
in this paper but will not from previous $q_{\rm c}$. Meanwhile, from our
$q_{\rm c}$, blue stragglers from the mass transfer between an AGB star and a
MS companion may be more numerous and have a wider range of orbital periods
than those from the other $q_{\rm c}$.


title: Charmed Scalar Resonances

abstract:
  It is pointed out that assigning D_{s0}^+(2317) to an iso-triplet tetra-quark
meson is favored by experiments. It also is discussed why its neutral and
doubly charged partners have never been observed in inclusive e^+e^-
annihilation. To search for them, hadronic weak decays of B mesons would be
better, and their production rates, Br(B_u^+ -> D^-D_{s0}^{++}(2317)) and
Br(B_d^0 ->antiD^0D_{s0}^{0}(2317)), would be around 10^{-3}.


title: Planet formation around stars of various masses: Hot super-Earths

abstract:
  We consider trends resulting from two formation mechanisms for short-period
super-Earths: planet-planet scattering and migration. We model scenarios where
these planets originate near the snow line in ``cold finger'' circumstellar
disks. Low-mass planet-planet scattering excites planets to low periastron
orbits only for lower mass stars. With long circularisation times, these
planets reside on long-period eccentric orbits. Closer formation regions mean
planets that reach short-period orbits by migration are most common around
low-mass stars. Above ~1 Solar mass, planets massive enough to migrate to
close-in orbits before the gas disk dissipates are above the critical mass for
gas giant formation. Thus, there is an upper stellar mass limit for
short-period super-Earths that form by migration. If disk masses are
distributed as a power law, planet frequency increases with metallicity because
most disks have low masses. For disk masses distributed around a relatively
high mass, planet frequency decreases with increasing metallicity. As icy
planets migrate, they shepherd interior objects toward the star, which grow to
~1 Earth mass. In contrast to icy migrators, surviving shepherded planets are
rocky. Upon reaching short-period orbits, planets are subject to evaporation
processes. The closest planets may be reduced to rocky or icy cores. Low-mass
stars have lower EUV luminosities, so the level of evaporation decreases with
decreasing stellar mass.


title: Dyons with hidden electric charges and the long-range magnetic force

abstract:
  When gauge U(1) is spontaneously broken, associated electric charges are
screened. We argue that corresponding magnetic charges, on the contrary,
produce long-range force. Some interesting consequences of this phenomenon are
also discussed.


title:
First Observation of the Cabibbo-suppressed Decays Xi_c+ -> Sigma+ pi-
  pi+ and Xi_c+ -> Sigma- pi+ pi+ and Measurement of their Branching Ratios

abstract:
  We report the first observation of two Cabibbo-suppressed decay modes, Xi_c+
-> Sigma+ pi- pi+ and Xi_c+ -> Sigma- pi+ pi+. We observe 59+/-14 over a
background of 87, and 22+/-8 over a background of 13 events, respectively, for
the signals. The data were accumulated using the SELEX spectrometer during the
1996-1997 fixed target run at Fermilab, chiefly from a 600GeV/c Sigma- beam.
The branching ratios of the decays relative to the Cabibbo--favored Xi_c+ ->
Xi- pi+ pi+ are measured to be B(Xi_c+ -> Sigma+ pi- pi+)/B(Xi_c+ -> Xi- pi+
pi+) = 0.48+/-0.20, and B(Xi_c+ -> Sigma- pi+ pi+)/B(Xi_c+ -> Xi- pi+ pi+) =
0.18+/-0.09, respectively. We also report branching ratios for the same decay
modes of the Lambda_c+ relative to Lambda_c+ -> p K- pi+.


title:
The influence of initial mass segregation on the runaway merging of
  stars

abstract:
  We have investigated the effect of initial mass segregation on the runaway
merging of stars. The evolution of multi-mass, dense star clusters was followed
by means of direct N-body simulations of up to 131.072 stars. All clusters
started from King models with dimensionless central potentials of 3.0 <= W_0 <=
9.0. Initial mass segregation was realized by varying the minimum mass of a
certain fraction of stars whose either (1) distances were closest to the
cluster center or (2) total energies were lowest. The second case is more
favorable to promote the runaway merging of stars by creating a high-mass core
of massive, low-energy stars. Initial mass segregation could decrease the
central relaxation time and thus help the formation of a high-mass core.
However, we found that initial mass segregation does not help the runaway
stellar merger to happen if the overall mass density profile is kept constant.
This is due to the fact that the collision rate of stars is not increased due
to initial mass segregation. Our simulations show that initial mass segregation
is not sufficient to allow runaway merging of stars to occur in clusters with
central densities typical for star clusters in the Milky Way.


title:
Automorphisms of two-dimensional RAAGs and partially symmetric
  automorphisms of free groups

abstract:
  We compute the virtual cohomological dimension (VCD) of the group of
partially symmetric outer automorphisms of a free group. We use this to obtain
new upper and lower bounds on the VCD of the outer automorphism group of a
two-dimensional right-angled Artin group. In the case of a right-angled group
with defining graph a tree, the bounds agree.


title:
Origin of the increased velocities of domain wall motions in soft
  magnetic thin-film nanostripes beyond the velocity-breakdown regime

abstract:
  It is known that oscillatory domain-wall (DW) motions in soft magnetic
thin-film nanostripes above the Walker critical field lead to a remarkable
reduction in the average DW velocities. In a much-higher-field region beyond
the velocity-breakdown regime, however, the DW velocities have been found to
increase in response to a further increase of the applied field. We report on
the physical origin and detailed mechanism of this unexpected behavior. We
associate the mechanism with the serial dynamic processes of the nucleation of
vortex-antivortex (V-AV) pairs inside the stripe or at its edges, the
non-linear gyrotropic motions of Vs and AVs, and their annihilation process.
The present results imply that a two-dimensional soliton model is required for
adequate interpretation of DW motions in the linear- and oscillatory-DW-motion
regimes as well as in the beyond-velocity-breakdown regime.


title:
Proving modularity for a given elliptic curve over an imaginary
  quadratic field

abstract:
  We present an algorithm to determine if the $L$-series associated to an
automorphic representation and the one associated to an elliptic curve over an
imaginary quadratic field agree. By the work of Harris-Soudry-Taylor, Taylor
and Berger-Harcos (cf. \cite{harris-taylor}, \cite{taylorII} and
\cite{berger-harcos}) we can associate to an automorphic representation a
family of compatible $p$-adic representations. Our algorithm is based on
Faltings-Serre's method to prove that $p$-adic Galois representations are
isomorphic.


title:
Fermi surface arcs and the infrared conductivity of underdoped
  YBa$_{2}$Cu$_{3}$O$_{6.50}$

abstract:
  We reanalyze the data on the in-plane far infrared conductivity of underdoped
orthoII YBa$_{2}$Cu$_{3}$O$_{6.50}$ (YBCO$_{6.50}$) in terms of a model in
which a pseudogap opens on part of the Fermi surface with the remaining ungaped
piece proportional to the temperature. The motivation for our model comes from
recent angle-resolved photoemission spectroscopy data in underdoped
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ (Bi-2212), which have revealed the existence
of arcs on the Fermi surface. We find the optical data to be consistent with
arc formation. In addition we find some evidence that the electronic states
lost below the pseudogap energy $\Delta_{pg}$ are recovered in the energy
region immediately above it at least for temperatures near $T_c$.


title:
Probabilistic analysis of three-player symmetric quantum games played
  using the Einstein-Podolsky-Rosen-Bohm setting

abstract:
  This paper extends our probabilistic framework for two-player quantum games
to the mutliplayer case, while giving a unified perspective for both classical
and quantum games. Considering joint probabilities in the standard
Einstein-Podolsky-Rosen-Bohm (EPR-Bohm) setting for three observers, we use
this setting in order to play general three-player non-cooperative symmetric
games. We analyze how the peculiar non-factorizable joint probabilities
provided by the EPR-Bohm setting can change the outcome of a game, while
requiring that the quantum game attains a classical interpretation for
factorizable joint probabilities. In this framework, our analysis of the
three-player generalized Prisoner's Dilemma (PD) shows that the players can
indeed escape from the classical outcome of the game, because of
non-factorizable joint probabilities that the EPR setting can provide. This
surprising result for three-player PD contrasts strikingly with our earlier
result for two-player PD, played in the same framework, in which even
non-factorizable joint probabilities do not result in escaping from the
classical consequence of the game.


title: Zeta Functions of Complexes Arising from PGL(3)

abstract:
  In this paper we obtain a closed form expression of the zeta function
$Z(X_\Gamma, u)$ of a finite quotient $X_\Gamma = \Gamma \backslash
PGL_3(F)/PGL_3(O_F)$ of the Bruhat-Tits building of $PGL_3$ over a
nonarchimedean local field $F$. Analogous to a graph zeta function,
$Z(X_\Gamma, u)$ is a rational function and it satisfies the Riemann hypothesis
if and only if $X_\Gamma$ is a Ramanujan complex.


title: Optical bistability at low light level due to collective atomic recoil

abstract:
  We demonstrate optical nonlinearities due to the interaction of weak optical
fields with the collective motion of a strongly dispersive ultracold gas. The
combination of a recoil-induced resonance (RIR) in the high gain regime and
optical waveguiding within the dispersive medium enables us to achieve a
collective atomic cooperativity of $275 \pm 50$ even in the absence of a
cavity. As a result, we observe optical bistability at input powers as low as
20 pW. The present scheme allows for dynamic optical control of the dispersive
properties of the ultracold gas using very weak pulses of light. The
experimental observations are in good agreement with a theoretical model.


Imagery of Diffusing Media by Heterodyne Holography


title: Mean-field model for magnetic orders in NpTGa5 with T=Co, Ni or Rh

abstract:
  Characteristics of magnetic transitions in NpTGa$_5$ with T=Co, Ni, Rh are
explained in a unified way with use of a crystalline electric field (CEF) model
of localized 5$f^4$ electrons. The model takes a CEF doublet and a singlet as
local states, and includes dipolar and quadrupolar intersite interactions in
the mean-field theory. Diverse ordering phenomena are derived depending on the
magnitude of interaction parameters, which qualitatively reproduce the
experimentally observed magnetic behaviors in NpTGa$_5$. The quadrupole degrees
of freedom are essential to the diverse magnetic orders. It is argued that
NpRhGa$_5$ is close to a multicritical point where quadrupoles and dipoles with
different directions are competing to order.


title:
Multi-valley spin relaxation in the presence of high in-plane electric
  fields in $n$-type GaAs quantum wells

abstract:
  Multi-valley spin relaxation in $n$-type GaAs quantum wells with in-plane
electric field is investigated at high temperature by means of kinetic spin
Bloch equation approach. The spin relaxation time first increases and then
decreases with electric field, especially when the temperature is relatively
low. We show that $L$ valleys play the role of a ``drain'' of the total spin
polarization due to the large spin-orbit coupling in $L$ valleys and the strong
$\Gamma$-$L$ inter-valley scattering, and thus can enhance spin relaxation of
the total system effectively when the in-plane electric field is high. Under
electric field, spin precession resulting from the electric-field-induced
magnetic field is observed. Meanwhile, due to the strong $\Gamma$-$L$
inter-valley scattering as well as the strong inhomogeneous broadening in $L$
valleys, electron spins in $L$ valleys possess almost the same damping rate and
precession frequency as those in $\Gamma$ valley. This feature still holds when
a finite static magnetic field is applied in Voigt configuration, despite that
the $g$-factor of $L$ valleys is much larger than that of $\Gamma$ valley.
Moreover, it is shown that the property of spin precession of the whole system
is dominated by electrons in $\Gamma$ valley. Temperature, magnetic field, and
impurity can affect spin relaxation in low electric field regime. However, they
are shown to have marginal influence in high electric field regime.


title: Bounds for the loss probability in large loss queueing systems

abstract:
  Let $\mathcal{G}(\frak{g}_1,\frak{g}_2)$ be the class of all probability
distribution functions of positive random variables having the given first two
moments $\frak{g}_1$ and $\frak{g}_2$. Let $G_1(x)$ and $G_2(x)$ be two
probability distribution functions of this class satisfying the condition
$|G_1(x)-G_2(x)|<\epsilon$ for some small positive value $\epsilon$ and let
$\widehat{G}_1(s)$ and, respectively, $\widehat{G}_2(s)$ denote their
Laplace-Stieltjes transforms. For real $\mu$ satisfying $\mu\frak{g}_1>1$ let
us denote by $\gamma_{G_1}$ and $\gamma_{G_2}$ the least positive roots of the
equations $z=\widehat{G}_1(\mu-\mu z)$ and $z=\widehat{G}_2(\mu-\mu z)$
respectively. In the paper, the upper bound for $|\gamma_{G_1}-\gamma_{G_2}|$
is derived. This upper bound is then used to find lower and upper bounds for
the loss probabilities in different large loss queueing systems.


title: Nikol'skii-type inequalities for rearrangement invariant spaces

abstract:
  In this paper we generalize the classical Nikol'skii inequality on the many
popular classes pairs of rearrangement invariant (r.i.) spaces and construct
some examples in order to show the exactness of our estimations.


title:
Gap opening with ordering in PrFe4P12 studied by local tunneling
  spectroscopy

abstract:
  We present measurements of the local tunneling density of states in the low
temperature ordered state of PrFe4P12. The temperature dependencies of the
Fermi level density of states and of the integrated density of states at low
bias voltages show anomalies at T=6.5 K, the onset of multipolar ordering as
detected by specific heat and other macroscopic measurements. In the ordered
phase, we find a local density of states with a V-shape form, indicating a
partial gap opening over the Fermi surface. The size of the gap according to
the tunneling spectra is about 2 meV.


title: Scaling-sharp dispersive estimates for the Korteweg-de Vries group

abstract:
  We prove weighted estimates on the linear KdV group, which are scaling sharp.
This kind of estimates are in the spirit of that used to prove small data
scattering for the generalized KdV equations.


title: Switching of the Mott transition based on the hole-driven MIT theory

abstract:
  Switching voltage of first-order metal-insulator transition (MIT) in VO_2, an
inhomogeneous strongly correlated system, is changed by irradiating an infrared
light with wavelength, 1.5 micrometer, and applying the electric field
(photo-induced switching). This was predicted in the hole-driven MIT theory in
which hole doping of a low concentration below 0.01% into conduction band
(Fermi surface) induces the abrupt MIT as correlation effect. The switching is
explained by the Mott transition not the Peierls transition.


title:
Macroscopic proof of the Jarzynski-Wojcik fluctuation theorem for heat
  exchange

abstract:
  In a recent work, Jarzynski and Wojcik (2004 Phys. Rev. Lett. 92, 230602)
have shown by using the properties of Hamiltonian dynamics and a statistical
mechanical consideration that, through contact, heat exchange between two
systems initially prepared at different temperatures obeys a fluctuation
theorem. Here, another proof is presented, in which only macroscopic
thermodynamic quantities are employed. The detailed balance condition is found
to play an essential role. As a result, the theorem is found to hold under very
general conditions.


title:
Determining membrane permeability of giant phospholipid vesicles from a
  series of videomicroscopy images

abstract:
  A technique for determining the permeability of a phospholipid membrane on a
single giant unilamellar vesicle (GUV) is described, which complements the
existing methods utilizing either a planar black lipid membrane or
sub-micrometre-sized liposomes. A single GUV is transferred using a
micropipette from a solution of a nonpermeable solute into an iso-osmolar
solution of a solute with a higher membrane permeability. Osmotical swelling of
the vesicle is monitored with a CCD camera mounted on a phase contrast
microscope, and a sequence of images is obtained. On each image, the points on
the vesicle contour are determined using Sobel filtering with adaptive
binarization threshold, and from these, the vesicle radius is calculated with a
great accuracy. From the time-dependence of the vesicle radius, the membrane
permeability is obtained. Using a test set of data, the method provided a
consistent estimate of the POPC membrane permeability for glycerol, P = 1.7 x
10^-8 m/s, with individual samples ranging from 1.61 x 10^-8 m/s to 1.98 x
10^-8 m/s. This value is ~40% lower than the one obtained on similar systems.
Possible causes for this discrepancy are discussed.


title:
The radio expansion and brightening of the very young supernova remnant
  G1.9+0.3

abstract:
  Recent radio observations of the small Galactic supernova remnant G1.9+0.3
made at 4.86 GHz with the VLA are presented, and compared with earlier
observations at 1.49 GHz which have a comparable resolution (10 x 4 arcsec^2).
These show that the radio emission from this remnant has expanded
significantly, by about 15 per cent over 23 years, with a current outer
diameter of approximately 92 arcsec. This expansion confirms that G1.9+0.3 is
the youngest Galactic remnant yet identified, only about 150 years old at most.
Recent, lower resolution, 1.43-GHz observations are also discussed, and the
integrated flux densities from these and the 4.86-GHz observations are compared
with earlier results. This shows that the integrated flux density of G1.9+0.3
has been increasing recently.


title:
Dispersion of Resonant Raman Peaks of CO and OH in SnO2, Mo1-x FexO2
  Thin Films and SiO2 bulk glass

abstract:
  Resonance Raman (RR) peaks of and stretching modes and their higher harmonics
have been observed superimposed on photoluminescence (PL) spectrum of thin
films. Commercial fluorine doped thin films deposited by sputtering on glass
and thin films deposited on Si by laser ablation have been studied. The
dispersions of CO and OH stretching RR modes are ~ 600 cm-1/eV and 800 cm-1
respectively. The dispersion of the third harmonic of CO stretching mode is ~
2000 cm-1/eV. Similar dispersion of RR peak of stretching modes and higher
harmonics superimposed on PL spectra has been observed in Mo1-xFexO2 thin films
and SiO2 bulk glass. Large dispersion of RR peaks seems to be a common property
of oxides with impurities of and .


title:
Romania in a post-credit crunch world? A cautionary tale from Australia
  and America

abstract:
  We present data on debt accumulation in Australia and the United States, and
tentative data on Romania, to pose the question of whether Romania might
experience a credit crunch as a result of the US subprime financial crisis. We
develop a model of a credit crunch in a pure credit economy with endogenous
money creation, to show how changes in bank lending practices and borrower
repayment behaviour can bring about an economic decline.


title:
Spectral analysis for one class of second-order indefinite
  non-self-adjoint differential operator pencil

abstract:
  The inverse problem for the differential operator pencil with complex
periodic potential and discontinuous coefficients on the axis is studied. Main
characteristics of the fundamental solutions are investigated, the spectrum of
the operator is studied. We give formulation of the inverse problem, prove a
uniqueness theorem and provide a constructive procedure for the solution of the
inverse problem


title: Energy dissipation statistics in the random fuse model

abstract:
  We study the statistics of the dissipated energy in the two-dimensional
random fuse model for fracture under different imposed strain conditions. By
means of extensive numerical simulations we compare different ways to compute
the dissipated energy. In the case of a infinitely slow driving rate
(quasi-static model) we find that the probability distribution of the released
energy shows two different scaling regions separated by a sharp energy
crossover. At low energies, the probability of having an event of energy $E$
decays as $\sim E^{-1/2}$, which is robust and independent of the energy
quantifier used (or lattice type). At high energies fluctuations dominate the
energy distribution leading to a crossover to a different scaling regime, $\sim
E^{-2.75}$, whenever the released energy is computed over the whole system. On
the contrary, strong finite-size effects are observed if we only consider the
energy dissipated at microfractures. In a different numerical experiment the
quasi-static dynamics condition is relaxed, so that the system is driven at
finite strain load rates, and we find that the energy distribution decays as
$\mathcal{P} (E) \sim E^{-1}$ for all the energy range.


title:
Pathways of bond topology transitions at the interface of silicon
  nanocrystals and amorphous silica matrix

abstract:
  The interface chemistry of silicon nanocrystals (NCs) embedded in amorphous
oxide matrix is studied through molecular dynamics simulations with the
chemical environment described by the reactive force field model. Our results
indicate that the Si NC-oxide interface is more involved than the previously
proposed schemes which were based on solely simple bridge or double bonds. We
identify different types of three-coordinated oxygen complexes, previously not
noted. The abundance and the charge distribution of each oxygen complex is
determined as a function of the NC size as well as the transitions among them.
The oxidation at the surface of NC induces tensile strain to Si-Si bonds which
become significant only around the interface, while the inner core remains
unstrained. Unlike many earlier reports on the interface structure, we do not
observe any double bonds. Furthermore, our simulations and analysis reveal that
the interface bond topology evolves among different oxygen bridges through
these three-coordinated oxygen complexes.


title: Theory Of Radiation And Absorption Of Deformed Field Quanta

abstract:
  We calculate the intensity of spontaneous radiation of a system of non-linear
quantum field, where the non-linearity is due to deformations of the Poison
brackets of the generalized coordinates and momenta.


title: A New Expression of Soliton Solution to the Ultradiscrete Toda Equation

abstract:
  A new type of multi-soliton solution to the ultradiscrete Toda equation is
proposed. The solution can be transformed into another expression of solution
in a perturbation form. A direct proof of the solution is also given.


title:
Reversal-free CaIIH profiles: a challenge for solar chromosphere
  modeling in quiet inter-network

abstract:
  We study chromospheric emission to understand the temperature stratification
in the solar chromosphere. We observed the intensity profile of the CaIIH line
in a quiet Sun region close to the disk center at the German Vacuum Tower
Telescope. We analyze over 10^5 line profiles from inter-network regions. For
comparison with the observed profiles, we synthesize spectra for a variety of
model atmospheres with a non local thermodynamic equilibrium (NLTE) radiative
transfer code. A fraction of about 25% of the observed CaIIH line profiles do
not show a measurable emission peak in H_{2v} and H_{2r} wavelength bands
(reversal-free). All of the chosen model atmospheres with a temperature rise
fail to reproduce such profiles. On the other hand, the synthetic calcium
profile of a model atmosphere that has a monotonic decline of the temperature
with height shows a reversal-free profile that has much lower intensities than
any observed line profile. The observed reversal-free profiles indicate the
existence of cool patches in the interior of chromospheric network cells, at
least for short time intervals. Our finding is not only in conflict with a
full-time hot chromosphere, but also with a very cool chromosphere as found in
some dynamic simulations.


title:
Mean-field equations for weakly nonlinear two-scale perturbations of
  forced hydromagnetic convection in a rotating layer

abstract:
  We consider stability of regimes of hydromagnetic thermal convection in a
rotating horizontal layer with free electrically conducting boundaries, to
perturbations involving large spatial and temporal scales. Equations governing
the evolution of weakly nonlinear mean perturbations are derived under the
assumption that the alpha-effect is insignificant in the leading order (e.g.,
due to a symmetry of the system). The mean-field equations generalise the
standard equations of hydromagnetic convection: New terms emerge -- a
second-order linear operator representing the combined eddy diffusivity, and
quadratic terms associated with the eddy advection. If the perturbed CHM regime
is non-steady and insignificance of the alpha-effect in the system does not
rely on the presence of a spatial symmetry, the combined eddy diffusivity
operator also involves a non-local pseudodifferential operator. If the
perturbed CHM state is almost symmetric, alpha-effect terms appear in the
mean-field equations as well. Near a point of a symmetry-breaking bifurcation,
cubic nonlinearity emerges in the equations. All the new terms are in general
anisotropic. A method for evaluation of their coefficients is presented; it
requires solution of a significantly smaller number of auxiliary problems than
in a straightforward approach.


title:
The Simplest Determination of the Thermodynamical Characteristics of
  Kerr-Newman Black Hole

abstract:
  In this work, generalizing our previous results, we determine in an original
and the simplest way three most important thermodynamical characteristics
(Bekenstein-Hawking entropy, Bekenstein quantization of the entropy or (outer)
horizon surface area and Hawking temperature) of Kerr-Newman black hole. We
start physically by assumption that circumference of Kerr-Newman black hole
(outer) horizon holds the natural (integer) number of corresponding reduced
Compton's wave length and use mathematically, practically, only simple
algebraic equations. (It is conceptually similar to Bohr's quantization
postulate in Bohr's atomic model interpreted by de Broglie relation.)


title:
Astrophysical constraints on the confining models : the Field Correlator
  Method

abstract:
  We explore the relevance of confinement in quark matter models for the
possible quark core of neutron stars. For the quark phase, we adopt the
equation of state (EoS) derived with the Field Correlator Method, extended to
the zero temperature limit. For the hadronic phase, we use the microscopic
Brueckner-Hartree-Fock many-body theory. We find that the currently adopted
value of the gluon condensate $G_2 \simeq 0.006-0.007 \rm {GeV^4}$, which gives
a critical temperature $T_c \simeq 170 \rm MeV$, produces maximum masses which
are only marginally consistent with the observational limit, while larger
masses are possible if the gluon condensate is increased.


title: Breakdown of fluctuation-dissipation relations in granular gases

abstract:
  A numerical molecular dynamics experiment measuring the two-time correlation
function of the transversal velocity field in the homogeneous cooling state of
a granular gas is reported. By measuring the decay rate and the amplitude of
the correlations, the accuracy of the Landau-Langevin equation of fluctuating
hydrodynamics is checked. The results indicate that although a Langevin
approach can be valid, the fluctuation-dissipation relation must be modified,
since the viscosity parameter appearing in it differs from the usual
hydrodynamic shear viscosity.


title: Special invited paper. Large deviations

abstract:
  This paper is based on Wald Lectures given at the annual meeting of the IMS
in Minneapolis during August 2005. It is a survey of the theory of large
deviations.


title: From Permutahedron to Associahedron

abstract:
  For each finite real reflection group $W$, we identify a copy of the type-$W$
simplicial generalised associahedron inside the corresponding simplicial
permutahedron. This defines a bijection between the facets of the generalised
associahedron and the elements of the type $W$ non-crossing partition lattice
which is more tractable than previous such bijections. We show that the
simplicial fan determined by this associahedron coincides with the Cambrian fan
for $W$.


title:
Transport coefficients of multi-particle collision algorithms with
  velocity-dependent collision rules

abstract:
  Detailed calculations of the transport coefficients of a recently introduced
particle-based model for fluid dynamics with a non-ideal equation of state are
presented. Excluded volume interactions are modeled by means of biased
stochastic multiparticle collisions which depend on the local velocities and
densities. Momentum and energy are exactly conserved locally. A general scheme
to derive transport coefficients for such biased, velocity dependent collision
rules is developed. Analytic expressions for the self-diffusion coefficient and
the shear viscosity are obtained, and very good agreement is found with
numerical results at small and large mean free paths. The viscosity turns out
to be proportional to the square root of temperature, as in a real gas. In
addition, the theoretical framework is applied to a two-component version of
the model, and expressions for the viscosity and the difference in diffusion of
the two species are given.


title: A change of variables theorem for the multidimensional Riemann integral

abstract:
  The most general change of variables theorem for the Riemann integral of
functions of a single variable has been published in 1961 (by Kestelman). In
this theorem, the substitution is made by an `indefinite integral', that is, by
a function of the form (t\mapsto c+\int_a^tg=:G(t)) where (g) is Riemann
integrable on ([a,b]) and (c) is any constant. We prove a multidimensional
generalization of this theorem for the case where (G) is injective -- using the
fact that the Riemann primitives are the same as those Lipschitz functions
which are almost everywhere strongly differentiable in ((a,b)). We prove a
generalization of Sard's lemma for Lipschitz functions of several variables
that are almost everywhere strongly differentiable, which enables us to keep
all our proofs within the framework of the Riemannian theory which was our aim.


title:
Multifractality at the quantum Hall transition: Beyond the parabolic
  paradigm

abstract:
  We present an ultra-high-precision numerical study of the spectrum of
multifractal exponents $\Delta_q$ characterizing anomalous scaling of wave
function moments $<|\psi|^{2q}>$ at the quantum Hall transition. The result
reads $\Delta_q = 2q(1-q)[b_0 + b_1(q-1/2)^2 + ...]$, with $b_0 = 0.1291\pm
0.0002$ and $b_1 = 0.0029\pm 0.0003$. The central finding is that the spectrum
is not exactly parabolic, $b_1\ne 0$. This rules out a class of theories of
Wess-Zumino-Witten type proposed recently as possible conformal field theories
of the quantum Hall critical point.


title: Relative homology and maximal l-orthogonal modules

abstract:
  Let $\L$ be an artin algebra. Iyama conjectures that the endomorphism ring of
any two maximal $l$-orthogonal modules, $M_1$ and $M_2$, are derived
equivalent. He proves the conjecture for $l=1$, and for $l>1$ he gives some
orthogonality condition on $M_1$ and $M_2$, such that the
$\End_\L(M_2)^\op$-$\End_\L(M_1)$-bimodule $\Hom_\L(M_2,M_1)$ is tilting, which
implies that the rings $\End_\L(M_2)$ and $\End_\L(M_1)$ are derived equivalent
(see \cite{H}). The purpose of this paper is to characterize tilting modules of
the form $\Hom_\L(M_2,M_1)$ in terms of the relative theories induced by the
$\L$-modules $M_1$ and $M_2$, thus getting a generilization of Iyama's result.


title:
Color Profiles of Disk Galaxies since z~1: Probing Outer Disk Formation
  Scenarios

abstract:
  We present deep color profiles for a sample of 415 disk galaxies within the
redshift range 0.1<z<=1.1, and contained in HST-ACS imaging of the GOODS-South
field (Giavalisco et al. 2004). For each galaxy, passband combinations are
chosen to obtain, at each redshift, the best possible aproximation to the
rest-frame u-g color. We find that objects which show a truncation in their
stellar disk (Type II objects) usually show a minimum in their color profile at
the break, or very near to it, with a maximum to minimum amplitude in color of
<~0.2 mag/arcsec^2, a feature which is persistent through the explored range of
redshifts (i.e. in the last ~8 Gyr). This color structure is in qualitative
agreement with recent model expectations (Roskar et al. 2008) where the break
of the surface brightness profiles is the result of the interplay between a
radial star formation cut-off and a redistribution of stellar mass by secular
processes.


title: Power Series Composition and Change of Basis

abstract:
  Efficient algorithms are known for many operations on truncated power series
(multiplication, powering, exponential, ...). Composition is a more complex
task. We isolate a large class of power series for which composition can be
performed efficiently. We deduce fast algorithms for converting polynomials
between various bases, including Euler, Bernoulli, Fibonacci, and the
orthogonal Laguerre, Hermite, Jacobi, Krawtchouk, Meixner and
Meixner-Pollaczek.


title: The glasma initial state at the LHC

abstract:
  We present results from numerical Classical Yang Mills calculations of the
initial stage Glasma field configurations in a relativistic heavy ion
collision. We compute the initial gluon multiplicity from RHIC to LHC energies.
The initial conditions for the classical field computation are taken from a
dipole model parametrization tested on HERA data, meaning that all the
parameters, including the normalization and the value of the saturation scale,
are fixed from DIS data.


title: Can Cosmological Constant be a Forbidden Zone (GAP) in Quantum Vacuum

abstract:
  In this work we suggest, without detailed mathematical analysis, a hypothesis
on the physical meaning of cosmological constant. It is primarily based on a
conceptual analogy with energy characteristics of the crystal lattice
structure, i.e. energy zones theory in solid state physics. Namely, according
to some theories (holographic principle, emergent gravity etc.) it is supposed
that empty space, i.e. quantum vacuum holds a structure like to crystal
lattice. It implies a possibility of the existence of totally occupied zones
consisting of many levels of the negative energies as well as at least one
negative energy forbidden zone, i.e. negative energy gap without any (occupied
or empty) level of the negative energy. We suppose that given negative energy
forbidden zone in the quantum vacuum represents effectively a positive energy
zone without quantum particles that corresponds to cosmological constant. Also
we suggest some other (less extravagant) model of the cosmological constant.
Here cosmological constant is usually considered as the effect of the quantum
vacuum fluctuations where problem of the cut-off can be solved quite simply
since here integration over unlimited domain of the quasi-momentums must be
changed by integration over one, finite "Brillouin zone".


title:
Off-critical Casimir effect in Ising Slabs with Symmetric Boundary
  Conditions in d=3

abstract:
  Extended de Gennes-Fisher (EdGF) local-functional method has been applied to
the thermodynamic Casimir effect {\it away} from the critical point for systems
in the Ising universality class confined between parallel plane plates with
symmetric boundary conditions (denoted $(ab)=(++)$). Results on the universal
scaling functions of the Casimir force $W_{++}(y)$ ($y$ is a
temperature-dependant scaling variable) and Gibbs adsorption $\tilde G(y)$ are
presented in spatial dimension $d=3$. Also, the mean-field form of the
universal scaling function of the Gibbs adsorption $\tilde G(y)$ is derived
within the local functional theory. Asymptotic behavior of $W_{++}(y)$ for very
large values of the scaling variable $y$ is analyzed in {\it general} dimension
$d$.


title: S-wave meson scattering up to 2 GeV and its spectroscopy

abstract:
  We have performed a thorough study of the meson-meson S-waves with isospin
(I) 0 and 1/2, up to sqrt(s) ~ 2 GeV. This is the first study that includes 13
channels that have their threshold below that energy. All the resonances below
2 GeV, namely the f_0(600) or sigma, f_0(980), f_0(1370), f_0(1500), f_0(1710)
and f_0(1790) for I=0, and the K*_0(800) or kappa, K*_0(1430) and K*_0(1950)
for I=1/2, are generated. We can then extract a clear picture of the
spectroscopy, finding that the f_0(1710), together with an important
contribution to the f_0(1500), are glueballs. Another pole, which corresponds
mainly to the f_0(1370), is a pure octet I=0 state, and does not mix with the
glueball.


title: Inter-band magnetoplasmons in mono- and bi-layer graphene

abstract:
  Collective excitations spectrum of Dirac electrons in mono and bilayer
graphene in the presence of a uniform magnetic field is investigated.
Analytical results for inter-Landau band plasmon spectrum within the
self-consistent-field approach are obtained. SdH type oscillations that are a
monotonic function of the magnetic field are observed in the plasmon spectrum
of both mono- and bi-layer graphene systems. The results presented are also
compared with those obtained in conventional 2DEG. The chiral nature of the
quasiparticles in mono and bilayer graphene system results in the observation
of $\pi$ and $2\pi$ Berry's phase in the SdH- type oscillations in the plasmon
spectrum.


title:
Random sampling of colourings of sparse random graphs with a constant
  number of colours

abstract:
  In this work we present a simple and efficient algorithm which, with high
probability, provides an almost uniform sample from the set of proper
k-colourings on an instance of a sparse random graph G(n,d/n), where k=k(d) is
a sufficiently large constant. Our algorithm is not based on the Markov Chain
Monte Carlo method (M.C.M.C.). Instead, we provide a novel proof of correctness
of our Algorithm that is based on interesting "spatial mixing" properties of
colourings of G(n,d/n). Our result improves upon previous results (based on
M.C.M.C.) that required a number of colours growing unboundedly with n.


title:
Covariance of dark energy parameters and sound speed constraints from
  large HI surveys

abstract:
  An interesting probe of the nature of dark energy is the measure of its sound
speed, $c_s$. We review the significance for constraining sound speed models of
dark energy using large neutral hydrogen (HI) surveys with the Square Kilometre
Array (SKA). Our analysis considers the effect on the sound speed measurement
that arises from the covariance of $c_s$ with the dark energy density,
$\Omega_\LLambda$, and a time-varying equation of state, $w(a)=w_0+(1-a)w_a$.
We find that the approximate degeneracy between dark energy parameters that
arises in power spectrum observations is lifted through redshift tomography of
the HI-galaxy angular power spectrum, resulting in sound speed constraints that
are not severely degraded. The cross-correlation of the galaxy and the
integrated Sachs-Wolfe (ISW) effect spectra contributes approximately 10
percent of the information that is needed to distinguish variations in the dark
energy parameters, and most of the discriminating signal comes from the galaxy
auto-correlation spectrum. We also find that the sound speed constraints are
weakly sensitive to the HI bias model. These constraints do not improve
substantially for a significantly deeper HI survey since most of the clustering
sensitivity to sound speed variations arises from $z \lsim 1.5$. A detection of
models with sound speeds close to zero, $c_s \lsim 0.01,$ is possible for dark
energy models with $w\gsim -0.9$.


title: Strong hydrodynamic limit for attractive particle systems on Z

abstract:
  We prove almost sure Euler hydrodynamics for a large class of attractive
particle systems on $\Z$ starting from an arbitrary initial profile. We
generalize earlier works by Sepp\"al\"ainen (1999) and Andjel et al. (2004).
Our constructive approach requires new ideas since the subadditive ergodic
theorem (central to previous works) is no longer effective in our setting.


title:
Theory and Applications of Two-dimensional, Null-boundary,
  Nine-Neighborhood, Cellular Automata Linear rules

abstract:
  This paper deals with the theory and application of 2-Dimensional,
nine-neighborhood, null- boundary, uniform as well as hybrid Cellular Automata
(2D CA) linear rules in image processing. These rules are classified into nine
groups depending upon the number of neighboring cells influences the cell under
consideration. All the Uniform rules have been found to be rendering multiple
copies of a given image depending on the groups to which they belong where as
Hybrid rules are also shown to be characterizing the phenomena of zooming in,
zooming out, thickening and thinning of a given image. Further, using hybrid CA
rules a new searching algorithm is developed called Sweepers algorithm which is
found to be applicable to simulate many inter disciplinary research areas like
migration of organisms towards a single point destination, Single Attractor and
Multiple Attractor Cellular Automata Theory, Pattern Classification and
Clustering Problem, Image compression, Encryption and Decryption problems,
Density Classification problem etc.


title: Quantitative predictions with detuned normal forms

abstract:
  The phase-space structure of two families of galactic potentials is
approximated with a resonant detuned normal form. The normal form series is
obtained by a Lie transform of the series expansion around the minimum of the
original Hamiltonian. Attention is focused on the quantitative predictive
ability of the normal form. We find analytical expressions for bifurcations of
periodic orbits and compare them with other analytical approaches and with
numerical results. The predictions are quite reliable even outside the
convergence radius of the perturbation and we analyze this result using
resummation techniques of asymptotic series.


title: Transport through evanescent waves in ballistic graphene quantum dots

abstract:
  We study the transport through evanescent waves in graphene quantum dots of
different geometries. The transmission is suppressed when the leads are
attached to edges of the same majority sublattice. Otherwise, the transmission
depends exponentially on the distance between leads in rectangular dots, and as
a power law in circular dots. The transmission through junctions where the
transmitted and reflected currents belong to the opposite valley as the
incoming one depends on details of the lattice structure at distances
comparable to the atomic spacing.


title: Secure Remote Voting Using Paper Ballots

abstract:
  Internet voting will probably be one of the most significant achievements of
the future information society. It will have an enormous impact on the election
process making it fast, reliable and inexpensive. Nonetheless, so far remote
voting is considered to be very difficult, as one has to take into account
susceptibility of the voter's PC to various cyber-attacks. As a result, most
the research effort is put into developing protocols and machines for poll-site
electronic voting. Although these solutions yield promising results, they
cannot be directly adopted to Internet voting because of secure platform
problem. However, the cryptographic components they utilize may be very useful.
This paper presents a scheme based on combination of mixnets and homomorphic
encryption borrowed from robust poll-site voting, along with techniques
recommended for remote voting -- code sheets and test ballots. The protocol
tries to minimize the trust put in voter's PC by making the voter responsible
for manual encryption of his vote. To achieve this, the voter obtains a paper
ballot that allows him to scramble the vote by performing simple operations
(lookup in a table). Creation of paper ballots, as well as decryption of votes,
is performed by a group of cooperating trusted servers. As a result, the scheme
is characterized by strong asymmetry -- all computations are carried out on the
server side. In consequence it does not require any additional hardware on the
voter's side, and offers distributed trust, receipt-freeness and verifiability.


title: Scalar meson mass from renormalized One Boson Exchange Potential

abstract:
  We determine the mass and strength of the scalar meson from NN scattering
data by renormalizing the One Boson Exchange Potential. This procedure provides
a great insensitivity to the unknown short distance interaction making the
vector mesons marginally important and allowing for SU(3) couplings in the 1S0
channel. The scalar meson parameters are tightly constrained by low energy np.
We discuss whether this scalar should be compared to the recent findings based
on the Roy equations analysis of pipi scattering.


title: Three-body structure of low-lying 12Be states

abstract:
  We investigate to what extent a description of 12Be as a three-body system
made of an inert 10Be-core and two neutrons is able to reproduce the
experimental 12Be data. Three-body wave functions are obtained with the
hyperspherical adiabatic expansion method. We study the discrete spectrum of
12Be, the structure of the different states, the predominant transition
strengths, and the continuum energy spectrum after high energy fragmentation on
a light target. Two 0+, one 2+, one 1- and one 0- bound states are found where
the first four are known experimentally whereas the 0- is predicted as an
isomeric state. An effective neutron charge, reproducing the measured B(E1)
transition and the charge rms radius in 11Be, leads to a computed B(E1)
transition strength for 12Be in agreement with the experimental value. For the
E0 and E2 transitions the contributions from core excitations could be more
significant. The experimental 10Be-neutron continuum energy spectrum is also
well reproduced except in the energy region corresponding to the 3/2- resonance
in 11Be where core excitations contribute.


title:
Run and tumble chemotaxis in a shear flow: the effect of temporal
  comparisons and other complications

abstract:
  Escherichia coli is a motile bacterium that moves up a chemoattractant
gradient by performing a biased random walk composed of alternating runs and
tumbles. This paper presents calculations of the chemotactic drift velocity vd
(the mean velocity up the chemoattractant gradient) of an E. coli cell
performing chemotaxis in a uniform, steady shear flow, with a weak
chemoattractant gradient at right angles to the flow. Extending earlier models,
a combined analytic and numerical approach is used to assess the effect of
several complications, namely (i) a cell cannot detect a chemoattractant
gradient directly but rather makes temporal comparisons of chemoattractant
concentration, (ii) the tumbles exhibit persistence of direction, meaning that
the swimming directions before and after a tumble are correlated, (iii) the
cell suffers random re-orientations due to rotational Brownian motion, and (iv)
the non-spherical shape of the cell affects the way that it is rotated by the
shear flow. These complications influence the dependence of vd on the shear
rate gamma. When they are all included, it is found that (a) shear disrupts
chemotaxis and shear rates beyond gamma = 2/second cause the cell to swim down
the chemoattractant gradient rather than up it, (b) in terms of maximising
drift velocity, persistence of direction is advantageous in a quiescent fluid
but disadvantageous in a shear flow, and (c) a more elongated body shape is
advantageous in performing chemotaxis in a strong shear flow.


title:
Non-perturbative time-dependent String Backgrounds and Axion-induced
  Optical Activity

abstract:
  Conformal invariance for bosonic strings in time-dependent backgrounds of
graviton, dilaton and Kalb-Ramond field is obtained by imposing Weyl-beta
functions to be homogeneous in time, to all orders in $\alpha^{'}$. This
construction is possible in any target space dimension, as a result of the
non-trivial background configurations. The electromagnetic effects of the
antisymmetric tensor field, when coupled to an Abelian (electromagnetic) gauge
field, are discussed in the framework of a four-dimensional Minkowski Universe,
for concreteness. Non-trivial optical activity is demonstrated, which
constitutes a way of detecting string-inspired axion/dilaton effects in such
models.


title: Information filtering based on wiki index database

abstract:
  In this paper we present a profile-based approach to information filtering by
an analysis of the content of text documents. The Wikipedia index database is
created and used to automatically generate the user profile from the user
document collection. The problem-oriented Wikipedia subcorpora are created
(using knowledge extracted from the user profile) for each topic of user
interests. The index databases of these subcorpora are applied to filtering
information flow (e.g., mails, news). Thus, the analyzed texts are classified
into several topics explicitly presented in the user profile. The paper
concentrates on the indexing part of the approach. The architecture of an
application implementing the Wikipedia indexing is described. The indexing
method is evaluated using the Russian and Simple English Wikipedia.


title:
Time-reversal of a wave packet emitted by an internal source: the
  perfect inverse filter

abstract:
  The time-reversal mirror (TRM) of acoustic waves is used as a focusing
technique that is robust against disorder and chaos. The propagation of an
ultrasonic pulse from the focal point is detected and recorded by a surrounding
array of transducers that enclose the cavity region. The registered signals are
then played-back in the reverse temporal sequence and an imperfect Loschmidt
echo is obtained. A similar technique developed in the quantum domain, the
perfect inverse filter (PIF), ensures an exact reversion. Applied to the
acoustical case, it allows an improvement in the design of a minimally invasive
inverse filter. Although that version of PIF accounts for external source
condition, now we propose a generalization where the initial excitation is
created inside the cavity. We present the theoretical principles for this form
of PIF and perform a numerical test in a multichannel system that improves the
focalization quality compared to the TRM version.


title: Continuous crystals and Duistermaat-Heckman measure for Coxeter groups

abstract:
  We introduce a notion of continuous crystal analogous, for general Coxeter
groups, to the combinatorial crystals introduced by Kashiwara in representation
theory of Lie algebras. We use a generalization of the Littelmann path model to
show the existence of the crystals, and study an associated Duistermaat-Heckman
measure, which we interpret in terms of Brownian motion. We also show that the
Littelmann path operators can be derived from simple considerations on
Sturm-Liouville equations.


title: On Lipschitz compactifications of trees

abstract:
  We study the Lipschitz structures on the geodesic compactification of a
regular tree, that are preserved by the automorphism group. They are shown to
be similar to the compactifications introduced by William Floyd, and a complete
description is given.


title:
A description of the Hubbard model on a square lattice consistent with
  its global $SO(3)\times SO(3)\times U(1)$ symmetry

abstract:
  In this paper a description of the Hubbard model on the square lattice with
nearest-neighbor transfer integral $t$, on-site repulsion $U$, and $N_a^2\gg 1$
sites consistent with its exact global $SO(3)\times SO(3)\times U(1)$ symmetry
is constructed. Our studies profit from the interplay of that recently found
global symmetry of the model on any bipartite lattice with the transformation
laws under a suitable electron - rotated-electron unitary transformation of a
well-defined set of operators and quantum objects. For $U/4t>0$ the occupancy
configurations of these objects generate the energy eigenstates that span the
one- and two-electron subspace. Such a subspace as defined in this paper
contains nearly the whole spectral weight of the excitations generated by
application onto the zero-spin-density ground state of one- and two-electron
operators. Our description involves three basic objects: charge $c$ fermions,
spin-1/2 spinons, and $\eta$-spin-1/2 $\eta$-spinons. Alike in chromodynamics
the quarks have color but all quark-composite physical particles are
color-neutral, the $\eta$-spinon (and spinons) that are not invariant under
that transformation have $\eta$ spin 1/2 (and spin 1/2) but are part of
$\eta$-spin-neutral (and spin-neutral) $2\nu$-$\eta$-spinon (and $2\nu$-spinon)
composite $\eta\nu$ fermions (and $s\nu$ fermions) where $\nu=1,2,...$ is the
number of $\eta$-spinon (and spinon) pairs.The description introduced here is
consistent with a Mott-Hubbard insulating ground state with antiferromagnetic
long-range order for half filling at $x=0$ hole concentration and a ground
state with short-range spin order for a well-defined range of finite hole
concentrations $x>0$.


title: 2-Primary Anick Fibrations

abstract:
  Cohen conjectured that for r>=2 there is a space T^2n+1(2^r) and a homotopy
fibration sequence Loop^2 S^2n+1 --> S^2n-1 --> T^2n+1(2^r) --> Loop S^2n+1
with the property that the left map composed with the double suspension, Loop^2
S^2n+1 --> S^2n-1 --> Loop^2 S^2n+1, is homotopic to the 2^r-power map. We
positively resolve this conjecture when r>=3. Several preliminary results are
also proved which are of interest in their own right.


title: Almost homogeneous manifolds with boundary

abstract:
  Let $\rho_0$ be an action of a Lie group on a manifold with boundary that is
transitive on the interior. We study the set of actions that are topologically
conjugate to $\rho_0$, up to smooth or analytic change of coordinates. We show
that in many cases, including the compactifications of negatively curved
symmetric spaces, this set is infinite.


title: Random Quantum Operations

abstract:
  We define a natural ensemble of trace preserving, completely positive quantum
maps and present algorithms to generate them at random. Spectral properties of
the superoperator Phi associated with a given quantum map are investigated and
a quantum analogue of the Frobenius-Perron theorem is proved. We derive a
general formula for the density of eigenvalues of Phi and show the connection
with the Ginibre ensemble of real non-symmetric random matrices. Numerical
investigations of the spectral gap imply that a generic state of the system
iterated several times by a fixed generic map converges exponentially to an
invariant state.


title: On the permanent of random Bernoulli matrices

abstract:
  We show that the permanent of an $n \times n$ matrix with iid Bernoulli
entries $\pm 1$ is of magnitude $n^{({1/2}+o(1))n}$ with probability $1-o(1)$.
In particular, it is almost surely non-zero.


title: Feedback spin resonance in superconducting CeCu$_2$Si$_2$ and CeCoIn$_5$

abstract:
  We show that the recently observed spin resonance modes in heavy-fermion
superconductors CeCoIn$_5$ and CeCu$_2$Si$_2$ are magnetic excitons originating
from superconducting quasiparticles. The wave vector ${\bf Q}$ of the resonance
state leads to a powerful criterion for the symmetry and node positions of the
unconventional gap function. The detailed analysis of the superconducting
feedback on magnetic excitations reveals that the symmetry of the
superconducting gap corresponds to a singlet $d_{x^2-y^2}$ state symmetry in
both compounds. In particular this resolves the long-standing ambiguity of the
gap symmetry in CeCoIn$_5$. We demonstrate that in both superconductors the
resonance peak shows a significant dispersion away from ${\bf Q}$ that should
be observed experimentally. Our results suggest a unifying nature of the
resonance peaks in the two heavy-fermion superconductors and in layered
cuprates.


title: Limiting fragmentation from scale-invariant merging of fast partons

abstract:
  Exploiting the idea that the fast partons of an energetic projectile can be
treated as sources of color radiation interpreted as wee partons, it is shown
that the recently observed property of extended limiting fragmentation implies
a scaling law for the rapidity distribution of fast partons. This leads to a
picture of a self-similar process where, for fixed total rapidity Y, the
sources merge with probability varying as 1/y.


title:
Inelastic effects in electron transport studied with wave packet
  propagation

abstract:
  A time-dependent approach is used to explore inelastic effects during
electron transport through few-level systems. We study a tight-binding chain
with one and two sites connected to vibrations. This simple but transparent
model gives insight about inelastic effects, their meaning and the
approximations currently used to treat them. Our time-dependent approach allows
us to trace back the time sequence of vibrational excitation and electronic
interference, the ibrationally introduced time delay and the electronic phase
shift. We explore a full range of parameters going from weak to strong
electron-vibration coupling, from tunneling to contact, from one-vibration
description to the need of including all vibrations for a correct description
of inelastic effects in transport. We explore the validity of single-site
resonant models as well as its extension to more sites via molecular orbitals
and the conditions under which multi-orbital, multi-vibrational descriptions
cannot be simplified. We explain the physical meaning of the spectral features
in the second derivative of the electron current with respect to the bias
voltage. This permits us to nuance the meaning of the energy value of dips and
peaks. Finally, we show that finite-band effects lead to electron
back-scattering off the molecular vibrations in the regime of high-conductance,
although the drop in conductance at the vibrational threshold is rather due to
the rapid variation of the vibronic density of states.


title: O(He) Stars

abstract:
  Spectral analyses of H-deficient post-AGB stars have shown that a small group
of four extremely hot objects exists which have almost pure He absorption-line
spectra in the optical. These are classified as O(He) stars. For their
evolution there are two scenarios: They could be the long-sought hot successors
of RCrB stars, which have not been identified up to now. If this turns out to
be true, then a third post-AGB evolutionary sequence is revealed, which is
probably the result of a double-degenerate merging process. An alternative
explanation might be that O(He) stars are post early-AGB stars. These depart
from the AGB just before they experience their first thermal pulse (TP) which
will then occur as a late thermal pulse (LTP). This would be a link to the
low-mass He-enriched sdO stars and low-mass, particularly He-rich PG1159 stars.


title:
The structure and chemistry of the massive shell around AFGL 2343: 29SiO
  and HCN as tracers of high-excitation regions

abstract:
  The yellow hypergiant stars (YHGs) are very massive objects that are expected
to pass through periods of intense mass loss during their evolution. Despite of
this, massive circumstellar envelopes have been found only in two of them,
IRC+10420 and AFGL 2343. The envelopes around these objects and the processes
that form them are poorly known. We aim to study the structure, dynamics and
chemistry of the envelope around AFGL 2343. We have obtained interferometric
maps of the rotational lines 29SiO J= 2-1, HCN J= 1-0 and SO J(K)= 2(2)-1(1)
towards AFGL 2343. We have used an LVG excitation model to analyze the new
observations and some previously published line profiles of AFGL 2343. The
analysis of the observational data and the fitting results show the presence of
a thin, hot and dense component within the previously identified CO shell. This
component can be associated with recently shocked gas, but it could also be due
to a phase of extremely copious mass loss. We suggest that this shell is the
responsible for the whole 29SiO emission and significantly contributes to the
HCN emission. The presence of such a dense shell rich in SiO can be related
with that previously found for IRC+10420, which was also suggested to result
from a shock. This may be a common feature in the evolution of these stars, as
a consequence of the episodic mass loss periods that they pass during their
evolution. We present new results for the mass loss pattern, the total mass of
the circumstellar envelope and the molecular abundances of some species in AFGL
2343.


title:
All you ever wanted to know about optical long baseline stellar
  interferometry, but were too shy to ask your adviser

abstract:
  I try to present a small view of the properties and issues related to
astronomical interferometry observations. I recall a bit of history of the
technique, give some basic assessments to the principle of interferometry, and
finally, describe physical processes and limitations that affect optical long
baseline interferometry and which are, in general, very useful for everyday
work. Therefore, this text is not intended to perform strong demonstrations and
show accurate results, but rather to transmit the general "feeling" one needs
to have to not be destabilised by the first contact to real world
interferometry.


title: Exciton and hole spin dynamics in ZnO

abstract:
  The carrier spin dynamics in ZnO is investigated by time-resolved optical
orientation experiments. We evidence a clear circular polarization of the
donor-bound exciton luminescence in both ZnO epilayer and non-intentionally
doped bulk ZnO. This allows us to measure the localized hole spin relaxation
time. We find $\tau^{s}_h$$\sim$350 ps at T=1.7 K in the ZnO epilayer. The
strong energy and temperature dependences of the photoluminescence polarization
dynamics are well explained by the fast free exciton spin relaxation time and
the ionization of bound excitons.


title:
A NLO analysis on fragility of dihadron tomography in high energy $AA$
  collisions

abstract:
  The dihadron spectra in high energy $AA$ collisions are studied within the
NLO pQCD parton model with jet quenching taken into account. The high $p_T$
dihadron spectra are found to be contributed not only by jet pairs close and
tangential to the surface of the dense matter but also by punching-through jets
survived at the center while the single hadron high $p_T$ spectra are only
dominated by surface emission. Consequently, the suppression factor of such
high-$p_T$ hadron pairs is found to be more sensitive to the initial gluon
density than the single hadron suppression factor.


title:
Constraints on the IR behavior of the ghost propagator in Yang-Mills
  theories

abstract:
  We present rigorous upper and lower bounds for the momentum-space ghost
propagator G(p) of Yang-Mills theories in terms of the smallest nonzero
eigenvalue (and of the corresponding eigenvector) of the Faddeev-Popov matrix.
We apply our analysis to data from simulations of SU(2) lattice gauge theory in
Landau gauge, using the largest lattice sizes to date. Our results suggest
that, in three and in four space-time dimensions, the Landau-gauge ghost
propagator is not enhanced as compared to its tree-level behavior. This is also
seen in plots and fits of the ghost dressing function. In the two dimensional
case, on the other hand, we find that G(p) diverges as p^{-2-2 kappa} with
kappa \approx 0.15, in agreement with Ref. [1]. We note that our discussion is
general, although we make an application only to pure gauge theory in Landau
gauge. Most of our simulations have been performed on the IBM supercomputer at
the University of Sao Paulo.


title: UV and FUV spectroscopy of the hybrid PG 1159-type central star NGC 7094

abstract:
  Previous studies aiming at the iron-abundance determination in three PG 1159
stars (K 1-16, PG 1159-035, NGC 7094) and a [WC]-PG 1159 transition star (Abell
78) have revealed that no object shows any iron line in the UV spectrum. The
stars are iron-deficient by at least 1 dex, typically. A possible explanation
is that iron nuclei were transformed by neutron captures into heavier elements
(s-process), however, the extent of the iron-destruction would be much stronger
than predicted by AGB star models. But if n-captures are the right explanation,
then we should observe an enrichment of trans-iron elements. In this paper we
report on our search for a possible nickel overabundance in one of the four Fe
deficient PG 1159 stars, namely the central star NGC 7094. We are unable to
identify any nickel line in HST and FUSE spectra and conclude that Ni is not
overabundant. It is conceivable that iron was transformed into even heavier
elements, but their identification suffers from the lack of atomic data.


title: Fast Conversion Algorithms for Orthogonal Polynomials

abstract:
  We discuss efficient conversion algorithms for orthogonal polynomials. We
describe a known conversion algorithm from an arbitrary orthogonal basis to the
monomial basis, and deduce a new algorithm of the same complexity for the
converse operation.


title: Preservation of Positivity by Dynamical Coarse-Graining

abstract:
  We compare different quantum Master equations for the time evolution of the
reduced density matrix. The widely applied secular approximation (rotating wave
approximation) applied in combination with the Born-Markov approximation
generates a Lindblad type master equation ensuring for completely positive and
stable evolution and is typically well applicable for optical baths. For phonon
baths however, the secular approximation is expected to be invalid. The usual
Markovian master equation does not generally preserve positivity of the density
matrix. As a solution we propose a coarse-graining approach with a dynamically
adapted coarse graining time scale. For some simple examples we demonstrate
that this preserves the accuracy of the integro-differential Born equation. For
large times we analytically show that the secular approximation master equation
is recovered. The method can in principle be extended to systems with a
dynamically changing system Hamiltonian, which is of special interest for
adiabatic quantum computation. We give some numerical examples for the
spin-boson model of cases where a spin system thermalizes rapidly, and other
examples where thermalization is not reached.


title:
The VLA 1.4GHz Survey of the Extended Chandra Deep Field South: First
  Data Release

abstract:
  We have observed the Extended Chandra Deep Field South (E-CDF-S) using a
mosaic of six deep Very Large Array (VLA) pointings at 1.4GHz. In this paper,
we present the survey strategy, description of the observations, and the first
data release. The observations were performed during June through September of
2007 and included from 15 to 17 ``classic'' VLA antennas and 6 to 11 that had
been retrofitted for the Expanded VLA (EVLA). The first data release consists
of a 34.1' x 34.1' image and the attendant source catalog. The image achieves
an rms sensitivity of 6.4 uJy per 2.8" x 1.6" beam in its deepest regions, with
a typical sensitivity of 8 uJy. The catalog is conservative in that it only
lists sources with peak flux densities greater than seven times the local rms
noise, yet it still contains 464 sources. Nineteen of these are complex sources
consisting of multiple components. Cross matching of the catalog to prior
surveys of the E-CDF-S confirms the linearity of the flux density calibration,
albeit with a slight possible offset (a few percent) in scale. Improvements to
the data reduction and source catalog are ongoing, and we intend to produce a
second data release in January 2009.


title:
The coalescence of invariant manifolds and the spiral structure of
  barred galaxies

abstract:
  In a previous paper (Voglis et al. 2006a, paper I) we demonstrated that, in a
rotating galaxy with a strong bar, the unstable asymptotic manifolds of the
short period family of unstable periodic orbits around the Lagrangian points
L$_1$ or L$_2$ create correlations among the apocentric positions of many
chaotic orbits, thus supporting a {\it spiral} structure beyond the bar. In the
present paper we present evidence that the unstable manifolds of {\it all} the
families of unstable periodic orbits near and beyond corotation contribute to
the same phenomenon. Our results refer to a N-Body simulation, a number of
drawbacks of which, as well as the reasons why these do not significantly
affect the main results, are discussed. We explain the dynamical importance of
the invariant manifolds as due to the fact that they produce a phenomenon of
`stickiness' slowing down the rate of chaotic escape in an otherwise
non-compact region of the phase space. We find a stickiness time of order 100
dynamical periods, which is sufficient to support a long-living spiral
structure. Manifolds of different families become important at different ranges
of values of the Jacobi constant. The projections of the manifolds of all the
different families in the configuration space produce a pattern due to the
`coalescence' of the invariant manifolds. This follows closely the maxima of
the observed $m=2$ component near and beyond corotation. Thus, the manifolds
support both the outer edge of the bar and the spiral arms.


title: Non-Markovian effects on the dynamics of entanglement

abstract:
  A procedure that allows to obtain the dynamics of $N$ independent bodies each
locally interacting with its own reservoir is presented. It relies on the
knowledge of single body dynamics and it is valid for any form of environment
noise. It is then applied to the study of non-Markovian dynamics of two
independent qubits, each locally interacting with a zero temperature reservoir.
It is shown that, although no interaction is present or mediated between the
qubits, there is a revival of their entanglement, after a finite period of time
of its complete disappearance.


title: Almost-sure Growth Rate of Generalized Random Fibonacci sequences

abstract:
  We study the generalized random Fibonacci sequences defined by their first
nonnegative terms and for $n\ge 1$, $F_{n+2} = \lambda F_{n+1} \pm F_{n}$
(linear case) and $\widetilde F_{n+2} = |\lambda \widetilde F_{n+1} \pm
\widetilde F_{n}|$ (non-linear case), where each $\pm$ sign is independent and
either $+$ with probability $p$ or $-$ with probability $1-p$ ($0<p\le 1$). Our
main result is that, when $\lambda$ is of the form $\lambda_k = 2\cos (\pi/k)$
for some integer $k\ge 3$, the exponential growth of $F_n$ for $0<p\le 1$, and
of $\widetilde F_{n}$ for $1/k < p\le 1$, is almost surely positive and given
by $$ \int_0^\infty \log x d\nu_{k, \rho} (x), $$ where $\rho$ is an explicit
function of $p$ depending on the case we consider, taking values in $[0, 1]$,
and $\nu_{k, \rho}$ is an explicit probability distribution on $\RR_+$ defined
inductively on generalized Stern-Brocot intervals. We also provide an integral
formula for $0<p\le 1$ in the easier case $\lambda\ge 2$. Finally, we study the
variations of the exponent as a function of $p$.


title: Ground-state two-spinon bonds in the Hubbard model on a square lattice

abstract:
  In this paper the spin configurations of the ground state and one- and
two-electron excited states of the Hubbard model on the square lattice are
studied. We profit from a general rotated-electron description, which is
consistent with the model global $SO(3)\times SO(3)\times U(1)$ symmetry. For
rotated electrons, doubly and single occupancy are good quantum numbers for
on-site repulsion $U>0$. The above states are within that description generated
by occupancy configurations of charge $c$ fermions and spin-singlet two-spinon
$s1$ bond particles. Those describe the charge and spin degrees of freedom,
respectively, of the rotated electrons that singly occupy sites. While the $c$
fermions have no internal structure, that of the spin-neutral $s1$
bond-particle occupancy configurations is here described in terms of spinon
occupancies of a well-defined effective spin lattice. In reference
\cite{companion} it is confirmed that our results contribute to the further
understanding of the role of electronic correlations in the spin spectrum of
the parent compound La$_2$CuO$_4$. They are also of interest for studies of
ultra-cold fermionic atoms on an optical lattice.


title: Tracing spiral density waves in M81

abstract:
  We use SPITZER IRAC 3.6 and 4.5micron near infrared data from the Spitzer
Infrared Nearby Galaxies Survey (SINGS), optical B, V and I and 2MASS Ks band
data to produce mass surface density maps of M81. The IRAC 3.6 and 4.5micron
data, whilst dominated by emission from old stellar populations, is corrected
for small-scale contamination by young stars and PAH emission. The I band data
are used to produce a mass surface density map by a B-V colour-correction,
following the method of Bell and de Jong. We fit a bulge and exponential disc
to each mass map, and subtract these components to reveal the non-axisymmetric
mass surface density. From the residual mass maps we are able to extract the
amplitude and phase of the density wave, using azimuthal profiles. The response
of the gas is observed via dust emission in the 8micron IRAC band, allowing a
comparison between the phase of the stellar density wave and gas shock. The
relationship between this angular offset and radius suggests that the spiral
structure is reasonably long lived and allows the position of corotation to be
determined.


title: Punch-through jets in $A+A$ collisions at RHIC/LHC

abstract:
  High $p_T$ single and dihadron production is studied within a NLO pQCD parton
model with jet quenching in high energy $A+A$ collisions at the RHIC/LHC
energy. A simultaneous $\chi^2$-fit to both single and dihadron spectra can be
achieved within a narrow range of energy loss parameter. Punch-through jets are
found to result in the dihadron suppression factor slightly more sensitive to
medium than the single hadron suppression factor at RHIC. Such jets at LHC are
found to dominate high $p_T$ dihadron production and the resulting dihadron
spectra are more sensitive to the initial parton distribution functions than
the single hadron spectra.


title:
Phase controlled superconducting proximity effect probed by tunneling
  spectroscopy

abstract:
  Using a dual-mode STM-AFM microscope operating below 50mK we measured the
Local Density of States (LDoS) along small normal wires connected at both ends
to superconductors with different phases. We observe that a uniform minigap can
develop in the whole normal wire and in the superconductors near the
interfaces. The minigap depends periodically on the phase difference. The
quasiclassical theory of superconductivity applied to a simplified 1D model
geometry accounts well for the data.


title:
Phase synchronization on scale-free and random networks in the presence
  of noise

abstract:
  In this work we investigate the stability of synchronized states for the
Kuramoto model on scale-free and random networks in the presence of white noise
forcing. We show that for a fixed coupling constant, the robustness of the
globally synchronized state against the noise is dependent on the noise
intensity on both kinds of networks. At low noise intensities the random
networks are more robust against losing the coherency but upon increasing the
noise, at a specific noise strength the synchronization among the population
vanishes suddenly. In contrast, on scale-free networks the global
synchronization disappears continuously at a much larger critical noise
intensity respect to the random networks.


title: Heralded generation of multiphoton entanglement

abstract:
  We present a scheme, based only on linear optics and standard photon
detection, that allows to generate heralded multiphoton entangled states of
arbitrary photon number from spontaneous parametric downconversion (PDC) in the
weak interaction regime. The scheme also works in the strong interaction
regime, i.e., for the production of large photon numbers, when photon-number
resolving detectors with nearly perfect quantum efficiency are used. In
addition, the same setup can be used for quantum metrology as multiphoton
interferometer with sensitivity at the Heisenberg limit.


title:
The square-lattice quantum liquid of charge c fermions and spin-neutral
  two-spinon s1 fermions

abstract:
  The momentum bands, energy dispersions, and velocities of the charge $c$
fermions and spin-neutral two-spinon $s1$ fermions of a square-lattice quantum
liquid referring to the Hubbard model on such a lattice of edge length $L$ in
the one- and two-electron subspace are studied. The model involves the
effective nearest-neighbor integral $t$ and on-site repulsion $U$ and can be
experimentally realized in systems of correlated ultra-cold fermionic atoms on
an optical lattice and thus our results are of interest for such systems. Our
investigations profit from a general rotated-electron description, which is
consistent with the model global $SO(3)\times SO(3)\times U(1)$ symmetry. For
the model in the one- and two-electron subspace the discrete momentum values of
the $c$ and $s1$ fermions are good quantum numbers so that in contrast to the
original strongly-correlated electronic problem their interactions are
residual. The use of our description renders an involved many-electron problem
into a quantum liquid with some similarities with a Fermi liquid.


title:
Dimensional regularization of the gravitational interaction of point
  masses in the ADM formalism

abstract:
  The ADM formalism for two-point-mass systems in $d$ space dimensions is
sketched. It is pointed out that the regularization ambiguities of the 3rd
post-Newtonian ADM Hamiltonian considered directly in $d=3$ space dimensions
can be cured by dimensional continuation (to complex $d$'s), which leads to a
finite and unique Hamiltonian as $d\to3$. Some so far unpublished details of
the dimensional-continuation computation of the 3rd post-Newtonian
two-point-mass ADM Hamiltonian are presented.


title:
The CMB Quadrupole depression produced by early fast-roll inflation:
  MCMC analysis of WMAP and SDSS data

abstract:
  Generically,the classical evolution of the inflaton has a brief fast roll
stage that precedes the slow roll regime. The fast roll stage leads to a purely
attractive potential for the curvature and tensor perturbations (this potential
is purely repulsive in slowroll). This attractive potential depresses the CMB
quadrupole moment for the curvature and B-mode spectra. A single new
cosmological parameter emerges: the comoving wavenumber k_1 characteristic
scale of this attractive potential.k_1 happens to exit the horizon precisely at
the transition from fast to slowroll.The fastroll stage dynamically modifies
the initial power spectrum by a transfer function D(k). We compute D(k) by
solving the inflaton evolution equations. D(k) suppresses the primordial power
for k < k_1 and enjoys the scaling property D(k) = Psi(k/k_1) where Psi(x) is
an universal function. We perform a MCMC analysis of the WMAP/SDSS data
including the fast-roll stage and find k_1 = 0.266/Gpc. The quadrupole mode k_Q
= 0.242/Gpc exits the horizon 1/10 of an efold before k_1. We compare the
fastroll fit with a fit with a sharp lower cutoff on the primordial power.
Fastroll provides a slightly better fit than a sharp cutoff for the TT,TE and
EE modes.Moreover, our fits provide non-zero lower bounds for r, while for the
other cosmological parameters we essentially get those of the LCDM model. The
fact that k_Q exits the horizon before the slowroll stage implies an upper
bound in the total number of efolds N_{tot} during inflation.Combining this
with estimates during the radiation dominated era we obtain N_{tot} ~ 66, with
the bounds 62 < N_{tot} < 82.We repeated the analysis with the
WMAP-5/ACBAR-2007/SDSS data confirming the overall picture.


title:
d-wave superconductivity in Hubbard model on the square lattice
  perturbed by weak 3D uniaxial anisotropy

abstract:
  The Hubbard model on a square lattice is one of the most studied
condensed-matter quantum problems.Here we find evidence that for intermediate
$U/4t$ values and a hole-concentration range $x\in (x_c,x_*)$ the ground state
of the Hubbard model on the square lattice perturbed by weak three-dimensional
(3D) uniaxial anisotropy has long-range d-wave superconducting order. Here $t$
is the effective nearest-neighbor transfer integral and $U$ the effective
on-site repulsion. The lower critical concentration $x_c$ involves the Ginzburg
number Gi and is approximately given by $x_c\approx {\rm Gi}+x_0\approx 0.05$.
Here $x_0<{\rm Gi}$ is a small critical hole concentration that marks a sharp
quantum phase transition from a Mott-Hubbard insulator with long-range
antiferromagnetic order for $x<x_0$ to an Anderson insulator with short-range
incommensurate spiral spin order for $x\in (x_0,x_c)$. The value of the
critical hole concentration $x_*$ depends on $U/4t$ and is given by $x_*\approx
0.27$ for $U/4t\approx 1.525$. The long-range d-wave superconducting order
emerges below a critical temperature $T_c$ for a hole concentration range
centered at $x_{op}= (x_c+x_*)/2\approx 0.16$. It results from the effects of
the residual interactions of the charge $c$ and spin-neutral two-spinon $s1$
fermions of Ref. \cite{companion2}, as a by-product of the short-range spin
correlations. The spin subsystem provides through such interactions the energy
needed for the effective pairing coupling between the $c$ fermions of the
virtual-electron pair configurations.


title: Barbero-Immirzi parameter in Regge calculus

abstract:
  We consider Regge calculus in the representation in terms of area tensors and
self- and antiselfdual connections generalised to the case of Holst action that
is standard Einstein action in the tetrad-connection variables plus topological
(on equations of motion for connections) term with coefficient $1/\gamma$,
$\gamma$ is Barbero-Immirzi parameter. The quantum measure is shown to
exponentially decrease with areas with typical cut-off scales $4\pi G$ and
$4\pi G\gamma$ in spacelike and timelike regions, respectively ($G$ is the
Newton constant).


title: Quantum teleportation in superconducting charge qubits

abstract:
  In this paper we propose a scheme to implement a quantum teleportation based
on the current experimental design [Nature (London) 431, 162 (2004); ibid 445,
515 (2007)] in which superconducting charge qubits are capacitively coupled to
a single high-Q superconducting coplanar resonator. As advantage of this
architecture, it permits the use of multiqubit gates between non-nearest qubits
and the realization of parallel gates. We consider the case of two qubits
inside the resonator, where the teleportation is accomplished.


title:
The propagator for the step potential and delta function potential using
  the path decomposition expansion

abstract:
  We present a derivation of the propagator for a particle in the presence of
the step and delta function potentials. These propagators are known, but we
present a direct path integral derivation, based on the path decomposition
expansion and the Brownian motion definition of the path integral. The
derivation exploits properties of the Catalan numbers, which enumerate certain
classes of lattice paths.


title: SN 2005 gj: Evidence for LBV supernovae progenitors?

abstract:
  There has been mounting observational evidence in favour of Luminous Blue
Variables (LBVs) being the direct progenitors of supernovae. Here we present
possibly the most convincing evidence yet for such progenitors. We find
multiple absorption component P-Cygni profiles of hydrogen and helium in the
spectrum of SN 2005gj, which we interpret as being an imprint of the
progenitors mass-loss history. Such profiles have previously only been detected
in Luminous Blue Variables. This striking resemblance of the profiles, along
with wind velocities and periods consistent with LBV's leads us to connect SN
2005gj to an LBV progenitor.


title:
One-electron scattering rate and normal-state linear-$T$ resistivity of
  the cuprates

abstract:
  Here we use a description of the electronic correlations contained in the
Hubbard model on the square-lattice perturbed by very weak three-dimensional
uniaxial anisotropy in terms of the residual interactions of charge $c$
fermions and spin-neutral composite two-spinon $s1$ fermions. Excellent
quantitative agreement with the anisotropic linear-$\omega$ one-electron
scattering rate and normal-state linear-$T$ resistivity observed in experiments
on hole-doped cuprates with critical concentrations $x_c\approx 0.05$ and
$x_*\approx 0.27$ is achieved. Our results provide strong evidence that the
normal-state linear-$T$ resistivity is a manifestation of low-temperature
scale-invariant physics.


title: Front propagation in A+B -> 2A reaction under subdiffusion

abstract:
  We consider an irreversible autocatalytic conversion reaction A+B -> 2A under
subdiffusion described by continuous time random walks. The reactants'
transformations take place independently on their motion and are described by
constant rates. The analog of this reaction in the case of normal diffusion is
described by the Fisher-Kolmogorov-Petrovskii-Piskunov (FKPP) equation leading
to the existence of a nonzero minimal front propagation velocity which is
really attained by the front in its stable motion. We show that for
subdiffusion this minimal propagation velocity is zero, which suggests
propagation failure.


title: The core flux of the brightest 10 micron galaxies in the southern sky

abstract:
  Aims. Near diffraction-limited images have been taken at 8.9, 11.9, and 12.9
micron for the brightest extragalactic sources in the southern sky, in order to
optimally plan N-band observations with MIDI (MID-infrared Interferometric
instrument) at the VLTI. Methods. We have assembled a sample of 21 objects
consisting of all the AGNs observable from Paranal observatory, Chile, plus
three non-AGN objects, with an estimated N-band flux greater than 400mJy. We
used the TIMMI2 Mid Infrared instrument mounted on the ESO's 3.6m telescope to
obtain near diffraction-limited images in order to establish the unresolved
core flux within < 0.5 arscsec. Results. Positions and core total fluxes were
obtained for all sources in our sample and compared with similar investigations
in the literature. We find that 15 AGN and the nuclear starburst in NGC 253
exhibit an unresolved core flux < 300mJy at 11.9 micron, making them promising
targets for MIDI at the VLTI. For extended sources, near diffraction-limited
images are presented and discussed.


title:
Entangled photon pairs produced by a quantum dot strongly coupled to a
  microcavity

abstract:
  We show theoretically that entangled photon pairs can be produced on demand
through the biexciton decay of a quantum dot strongly coupled to the modes of a
photonic crystal. The strong coupling allows to tune the energy of the mixed
exciton-photon (polariton) eigenmodes, and to overcome the natural splitting
existing between the exciton states coupled with different linear polarizations
of light. Polariton states are moreover well protected against dephasing due to
their lifetime ten to hundred times shorter than that of a bare exciton. Our
analysis shows that the scheme proposed can be achievable with the present
technology.


title: Manifestation of pseudogap in ab-plane optical characteristics

abstract:
  A model in which a gap forms in the renormalized electronic density of state
(DOS) with missing states recovered just above the pseudogap $\Delta_{pg}$, is
able to give a robust description of the striking, triangular like, peak seen
in the real part of the optical self-energy of underdoped cuprates. We use this
model to explore the effect of the pseudogap on the real part of the optical
conductivity and on the partial sum rule associated with it. An important
result is that the optical spectral weight redistributes over a much larger
frequency window than it does in the DOS.


title:
On the probabilistic description of a multipartite correlation scenario
  with arbitrary numbers of settings and outcomes per site

abstract:
  We consistently formalize the probabilistic description of multipartite joint
measurements performed on systems of any nature. This allows us: (1) to specify
in probabilistic terms the difference between nonsignaling, the Einstein-
Podolsky-Rosen (EPR) locality and Bell's locality; (2) to introduce the notion
of an LHV model for an S_{1}x...xS_{N}-setting N-partite correlation
experiment, with outcomes of any spectral type, discrete or continuous, and to
prove both general and specific "quantum" statements on an LHV simulation in an
arbitrary multipartite case; (3) to classify LHV models for a multipartite
quantum state, in particular, to show that any N-partite quantum state, pure or
mixed, admits an Sx1x...x1 -setting LHV description; (4) to evaluate a
threshold visibility for a noisy bipartite quantum state to admit an S_{1}xS_
{2}-setting LHV description under any generalized quantum measurements of two
parties. In a sequel to this paper, we shall introduce a single general
representation incorporating in a unique manner all Bell-type inequalities for
either joint probabilities or correlation functions that have been introduced
or will be introduced in the literature.


title:
Localized and periodic exact solutions to the nonlinear Schrodinger
  equation with spatially modulated parameters: Linear and nonlinear lattices

abstract:
  Using similarity transformations we construct explicit solutions of the
nonlinear Schrodinger equation with linear and nonlinear periodic potentials.
We present explicit forms of spatially localized and periodic solutions, and
study their properties. We put our results in the framework of the exploited
perturbation techniques and discuss their implications on the properties of
associated linear periodic potentials and on the possibilities of stabilization
of gap solitons using polychromatic lattices.


title:
Growth rate for the expected value of a generalized random Fibonacci
  sequence

abstract:
  A random Fibonacci sequence is defined by the relation g_n = | g_{n-1} +/-
g_{n-2} |, where the +/- sign is chosen by tossing a balanced coin for each n.
We generalize these sequences to the case when the coin is unbalanced (denoting
by p the probability of a +), and the recurrence relation is of the form g_n =
|\lambda g_{n-1} +/- g_{n-2} |. When \lambda >=2 and 0 < p <= 1, we prove that
the expected value of g_n grows exponentially fast. When \lambda = \lambda_k =
2 cos(\pi/k) for some fixed integer k>2, we show that the expected value of g_n
grows exponentially fast for p>(2-\lambda_k)/4 and give an algebraic expression
for the growth rate. The involved methods extend (and correct) those introduced
in a previous paper by the second author.


title: Causal models have no complete axiomatic characterization

abstract:
  Markov networks and Bayesian networks are effective graphic representations
of the dependencies embedded in probabilistic models. It is well known that
independencies captured by Markov networks (called graph-isomorphs) have a
finite axiomatic characterization. This paper, however, shows that
independencies captured by Bayesian networks (called causal models) have no
axiomatization by using even countably many Horn or disjunctive clauses. This
is because a sub-independency model of a causal model may be not causal, while
graph-isomorphs are closed under sub-models.