title:
Extreme Synergy in a Retinal Code: Spatiotemporal Correlations Enable
  Rapid Image Reconstruction

abstract:
  Over the brief time intervals available for processing retinal output,
roughly 50 to 300 msec, the number of extra spikes generated by individual
ganglion cells can be quite variable. Here, computer-generated spike trains
were used to investigate how signal/noise might be improved by utilizing
spatiotemporal correlations among retinal neurons responding to large,
contiguous stimuli. Realistic correlations were produced by modulating the
instantaneous firing probabilities of all stimulated neurons by a common
oscillatory input whose amplitude and temporal structure were consistent with
experimentally measured field potentials and correlograms. Whereas previous
studies have typically measured synergy between pairs of ganglion cells
examined one at a time, or alternatively have employed optimized linear filters
to decode activity across larger populations, the present study investigated a
distributed, non-linear encoding strategy by using Principal Components
Analysis (PCA) to reconstruct simple visual stimuli from up to one million
oscillatory pairwise correlations extracted on single trials from
massively-parallel spike trains as short as 25 msec in duration. By integrating
signals across retinal neighborhoods commensurate in size to classical
antagonistic surrounds, the first principal component of the pairwise
correlation matrix yielded dramatic improvements in signal/noise without
sacrificing fine spatial detail. These results demonstrate how local intensity
information can distributed across hundreds of neurons linked by a common,
stimulus-dependent oscillatory modulation, a strategy that might have evolved
to minimize the number of spikes required to support rapid image
reconstruction.


title: Information theoretic approach to interactive learning

abstract:
  The principles of statistical mechanics and information theory play an
important role in learning and have inspired both theory and the design of
numerous machine learning algorithms. The new aspect in this paper is a focus
on integrating feedback from the learner. A quantitative approach to
interactive learning and adaptive behavior is proposed, integrating model- and
decision-making into one theoretical framework. This paper follows simple
principles by requiring that the observer's world model and action policy
should result in maximal predictive power at minimal complexity. Classes of
optimal action policies and of optimal models are derived from an objective
function that reflects this trade-off between prediction and complexity. The
resulting optimal models then summarize, at different levels of abstraction,
the process's causal organization in the presence of the learner's actions. A
fundamental consequence of the proposed principle is that the learner's optimal
action policies balance exploration and control as an emerging property.
Interestingly, the explorative component is present in the absence of policy
randomness, i.e. in the optimal deterministic behavior. This is a direct result
of requiring maximal predictive power in the presence of feedback.


title: Constructing Textures in Extended Quark-Lepton Complementarity

abstract:
  We systematically construct an extensive list of realistic mass matrix
textures for leptons. For this set of matrices, we discuss the parameter space,
and illustrate how these textures could be generated in explicit models from
flavor symmetries.


title:
The XMM-LSS survey: the Class 1 cluster sample over the initial 5 square
  degrees and its cosmological modelling

abstract:
  We present a sample of 29 galaxy clusters from the XMM-LSS survey over an
area of some 5deg2 out to a redshift of z=1.05. The sample clusters, which
represent about half of the X-ray clusters identified in the region, follow
well defined X-ray selection criteria and are all spectroscopically confirmed.
For all clusters, we provide X-ray luminosities and temperatures as well as
masses. The cluster distribution peaks around z=0.3 and T =1.5 keV, half of the
objects being groups with a temperature below 2 keV. Our L-T(z) relation points
toward self-similar evolution, but does not exclude other physically plausible
models. Assuming that cluster scaling laws follow self-similar evolution, our
number density estimates up to z=1 are compatible with the predictions of the
concordance cosmology and with the findings of previous ROSAT surveys. Our well
monitored selection function allowed us to demonstrate that the inclusion of
selection effects is essential for the correct determination of the evolution
of the L-T relation, which may explain the contradictory results from previous
studies. Extensive simulations show that extending the survey area to 10deg2
has the potential to exclude the non-evolution hypothesis, but that constraints
on more refined ICM models will probably be limited by the large intrinsic
dispersion of the L-T relation. We further demonstrate that increasing the
dispersion in the scaling laws increases the number of detectable clusters,
hence generating further degeneracy [in addition to sigma8, Omega_m, L(M,z) and
T(M,z)] in the cosmological interpretation of the cluster number counts. We
provide useful empirical formulae for the cluster mass-flux and mass-count-rate
relations as well as a comparison between the XMM-LSS mass sensitivity and that
of forthcoming SZ surveys.


title:
Off-center impurity in alkali halides: reorientation, electric
  polarization and pairing to F center. I. Basic equations

abstract:
  Extending earlier work on a vibronic theory of the FA centers in alkali
halides, the reorientation is now considered of an off-center Li+ impurity,
either isolated or near an F center. We derive analytically periodic potential
energy barriers between metastable reorientational off-center sites, the
barriers hindering the impurity rotation around the normal lattice site.
Applying to a specific model, electron-vibrational mode coupling constants are
calculated up to 3rd order of the expansion of the coupling energy in the T1u
mode coordinates. The 3rd order coupling brings about additional
renormalization of the reorientation controlling vibrational frequency.


title: Rapid roll Inflation with Conformal Coupling

abstract:
  Usual inflation is realized with a slow rolling scalar field minimally
coupled to gravity. In contrast, we consider dynamics of a scalar with a flat
effective potential, conformally coupled to gravity. Surprisingly, it contains
an attractor inflationary solution with the rapidly rolling inflaton field. We
discuss models with the conformal inflaton with a flat potential (including
hybrid inflation). There is no generation of cosmological fluctuations from the
conformally coupled inflaton. We consider realizations of modulated
(inhomogeneous reheating) or curvaton cosmological fluctuations in these
models. We also implement these unusual features for the popular
string-theoretic warped inflationary scenario, based on the interacting D3-anti
D3 branes. The original warped brane inflation suffers a large inflaton mass
due to conformal coupling to 4-dimensional gravity. Instead of considering this
as a problem and trying to cure it with extra engineering, we show that warped
inflation with the conformally coupled, rapidly rolling inflaton is yet
possible with N=37 efoldings, which requires low energy scales 1-100 TeV of
inflation. Coincidentally, the same warping numerology can be responsible for
the hierarchy. It is shown that the scalars associated with angular isometries
of the warped geometry of compact manifold (e.g. S^3 of KS geometry) have
solutions identical to conformally coupled modes and also cannot be responsible
for cosmological fluctuations. We discuss other possibilities.


title:
Charge-transfer photodissociation of adsorbed molecules via electron
  image states

abstract:
  The 248nm and 193nm photodissociation of submonolayer quantities of CH$_3$Br
and CH$_3$I adsorbed on thin layers of n-hexane indicate that the dissociation
is caused by dissociative electron attachment from sub-vacuum level
photoelectrons created in the copper substrate. The characteristics of this
photodissociation-- translation energy distributions and coverage dependences
show that the dissociation is mediated by an image potential state which
temporarily traps the photoelectrons near the n-hexane--vacuum interface, and
then the charge transfers from this image state to the affinity level of a
co-adsorbed halomethane which then dissociates.


title: Bessel potentials and optimal Hardy and Hardy-Rellich inequalities

abstract:
  We give necessary and sufficient conditions on a pair of positive radial
functions V and W on a ball B of radius R in R^n,$n \geq 1$, so that the
following inequalities hold for all $u \in C_{0}^{\infty}(B)$:
  $\int_{B}V(x)|\nabla u |^{2}dx \geq \int_{B} W(x)u^2dx$, and
$\int_{B}V(x)|\Delta u |^{2}dx \geq \int_{B} W(x)|\nabla
u|^{2}dx+(n-1)\int_{B}(\frac{V(x)}{|x|^2}-\frac{V_r(|x|)}{|x|})|\nabla u|^2dx$.
  This characterization makes a very useful connection between Hardy-type
inequalities and the oscillatory behaviour of certain ordinary differential
equations, and helps in the identification of a large number of such couples
(V, W)
  - that we call Bessel pairs -as well as the best constants in the
corresponding inequalities. This allows us to improve, extend, and unify many
results -old and new- about Hardy and Hardy-Rellich type inequalities, such as
those obtained by Caffarelli-Kohn-Nirenberg, Brezis-Vazquez, Wang-Willem,
Adimurthi-Chaudhuri-Ramaswamy, Filippas-Tertikas, Adimurthi-Grossi -Santra,
Tertikas-Zographopoulos, and Blanchet-Bonforte-Dolbeault-Grillo-Vasquez.


title: Pion Polarizabilities and Volume Effects in Lattice QCD

abstract:
  We use chiral perturbation theory to study the extraction of pion
electromagnetic polarizabilities from lattice QCD. Chiral extrapolation
formulae are derived for partially quenched QCD, and quenched QCD simulations.
On a torus, volume dependence of electromagnetic observables is complicated by
SO(4) breaking, as well as photon zero-mode interactions. We determine finite
volume corrections to the Compton scattering tensor of pions. We argue,
however, that such results cannot be used to ascertain volume corrections to
polarizabilities determined in lattice QCD with background field methods.
Connection is lacking because momentum expansions are not permitted in finite
volume. Our argument also applies to form factors. Volume effects for
electromagnetic moments cannot be deduced from finite volume form factors.


title:
Symmetry breaking effects upon bipartite and multipartite entanglement
  in the XY model

abstract:
  We analyze the bipartite and multipartite entanglement for the ground state
of the one-dimensional XY model in a transverse magnetic field in the
thermodynamical limit. We explicitly take into account the spontaneous symmetry
breaking in order to explore the relation between entanglement and quantum
phase transitions. As a result we show that while both bipartite and
multipartite entanglement can be enhanced by spontaneous symmetry breaking deep
into the ferromagnetic phase, only the latter is affected by it in the vicinity
of the critical point. This result adds to the evidence that multipartite, and
not bipartite, entanglement is the fundamental indicator of long range
correlations in quantum phase transitions.


title: Symplectic embeddings of polydisks

abstract:
  If P is a polydisk with radii R_1 < ... < R_n and P' is a polydisk with radii
R'_1 < ... < R'_n, then we construct a symplectic embedding from P into P'
provided that C(n) R_1 < R'_1 and C(n) R_1 ... R_n < C(n) R'_1 ... R'_n. Up to
a constant factor, these conditions are optimal.


title: Bloch-Siegert shift for multiphoton resonances

abstract:
  Recently there has been theoretical and experimental interest in
Bloch-Siegert shifts in an intense photon field. A perturbative treatment
becomes difficult in this multiphoton regime. We present a unitary transform
and rotated model, which allows us to get accurate results away from the level
anticrossings. A simple variational energy estimate leads to a new expression
for the dressed two-level system energy which is accurate, and useful over a
wide range of the dimensionless coupling constant.


title: The use of genetic algorithm to model protoplanetary discs

abstract:
  The protoplanetary discs of T Tauri and Herbig Ae/Be stars have been studied
by using geometric disc models to fit their spectral energy distribution (SED).
The simulations provide means to reproduce the signatures of different
circumstellar structures, which are related to different levels of infrared
excess. Aiming to improve our previous model that assumed a simple flat disc
configuration, in the present work we adopt a reprocessing flared disc model
that considers hydrostatic, radiative equilibrium (Dullemond et al. 2001). We
developed a method to optimise the parameters estimation based on genetic
algorithms (GA). This paper is dedicated to describe the implementation of the
new code, which has been applied for Herbig stars from the Pico dos Dias Survey
catalogue, in order to illustrate the quality of the fitting for a variety of
SED shapes. The star AB Aur was used as a test of the GA parameters estimation,
demonstrating that the new code reproduces successfully a canonical example of
the flared disc model. The GA method gives good quality of fittings, but the
range of input parameters must be chosen with caution, since unrealistic disc
parameters can be derived. The flared disc model is confirmed to fit the
flattened SEDs typical from Herbig stars, however the embedded objects
(increasing SED slope) and debris discs (steeper SED) are not well fitted with
this configuration. Even considering the limitation of the derived parameters,
the automatic process of SED fitting provides an interesting tool for the
statistical analysis of the circumstellar luminosity of large samples of young
stars.


title: W-pair production in Unparticle Physics

abstract:
  We consider the $W$-pair production for both $e^+e^-$ and hadron colliders in
the context of unparticle physics associated with the scale invariant sector
proposed by Georgi. We have shown that the unparticle contributions are quite
comparable with standard model (SM) specially for low values of non-integral
scaling dimension $ (d_{\cal U}) $ and hence it is worthwhile to explore in
future colliders.


title: Level Splitting in Association with the Multiphoton Bloch-Siegert Shift

abstract:
  We present a unitary equivalent spin-boson Hamiltonian in which terms can be
identified which contribute to the Bloch-Siegert shift, and to the level
splittings at the anticrossings associated with the Bloch-Siegert resonances.
First-order degenerate perturbation theory is used to develop approximate
results in the case of moderate coupling for the level splitting.


title:
An investigation of the origin of soft X-ray excess emission from
  Narrow-line Seyfert 1 galaxies Akn564 and Mrk1044

abstract:
  We investigate the origin of the soft X-ray excess emission from narrow-line
Seyfert 1 galaxies Akn564 and Mrk1044 using XMM-Newton observations. We find
clear evidence for time delays between the soft and hard X-ray emission from
Akn564 based on a 100ks long observation. The variations in the 4-10keV band
lag behind that in the 0.2-0.5keV band by 1768+/-122s. The full band power
density spectrum (PDS) of Akn~564 has a break at ~1.2e-3Hz with power-law
indices of ~1 and ~3 below and above the break. The hard (3-10keV) band PDS is
stronger and flatter than that in the soft (0.2-0.5keV) band. Based on a short
observation of Mrk1044, we find no correlation between the 0.2-0.3keV and
5-10keV bands at zero lag. These observations imply that the soft excess is not
the reprocessed hard X-ray emission. The high resolution spectrum of Akn564
obtained with the RGS shows evidence for a highly ionized and another weakly
ionized warm absorber medium. The smeared wind and blurred ionized reflection
models do not describe the pn data adequately. The spectrum is consistent with
a complex model consisting of optically thick Comptonization in a cool plasma
for the soft excess and a steep power-law, modified by two warm absorber media
as inferred from the RGS data and the foreground Galactic absorption. The
smeared wind and optically thick Comptonization models both describe the
spectrum of Mrk1044 satisfactorily, but the ionized reflection model requires
extreme parameters. The data suggest two component corona -- a cool, optically
thick corona for the soft excess and a hot corona for the power-law component.
The existence of a break in the soft band PDS suggests a compact cool corona
that can either be an ionized surface of the inner disk or an inner optically
thick region coupled to a truncated disk.


title:
Double Coronal Hard and Soft X-ray Source Observed by RHESSI: Evidence
  for Magnetic Reconnection and Particle Acceleration in Solar Flares

abstract:
  We present data analysis and interpretation of an M1.4-class flare observed
with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) on April
30, 2002. This event, with its footpoints occulted by the solar limb, exhibits
a rarely observed, but theoretically expected, double-source structure in the
corona. The two coronal sources, observed over the 6-30 keV range, appear at
different altitudes and show energy-dependent structures with the higher-energy
emission being closer together. Spectral analysis implies that the emission at
higher energies in the inner region between the two sources is mainly
nonthermal, while the emission at lower energies in the outer region is
primarily thermal. The two sources are both visible for about 12 minutes and
have similar light curves and power-law spectra above about 20 keV. These
observations suggest that the magnetic reconnection site lies between the two
sources. Bi-directional outflows of the released energy in the form of
turbulence and/or particles from the reconnection site can be the source of the
observed radiation. The spatially resolved thermal emission below about 15 keV,
on the other hand, indicates that the lower source has a larger emission
measure but a lower temperature than the upper source. This is likely the
result of the differences in the magnetic field and plasma density of the two
sources.


title:
Globular Cluster Abundances from High-Resolution Integrated Light
  Spectra, I: 47 Tuc

abstract:
  We describe the detailed chemical abundance analysis of a high-resolution
(R~35,000), integrated-light (IL), spectrum of the core of the Galactic
globular cluster 47 Tuc, obtained using the du Pont echelle at Las Campanas. We
develop an abundance analysis strategy that can be applied to spatial
unresolved extra- galactic clusters. We have computed abundances for Na, Mg,
Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Ba, La, Nd and Eu. For an
analysis with the known color-magnitude diagram (cmd) for 47 Tuc we obtain a
mean [Fe/H] value of -0.75 +/-0.026+/-0.045 dex (random and systematic error),
in good agreement with the mean of 5 recent high resolution abundance studies,
at -0.70 dex. Typical random errors on our mean [X/Fe] ratios are 0.07-0.10
dex, similar to studies of individual stars in 47 Tuc, although Na and Al
appear enhanced, perhaps due to proton burning in the most luminous cluster
stars. Our IL abundance analysis with an unknown cmd employed theoretical
Teramo isochrones; however, we apply zero-point abundance corrections to
account for the factor of 3 underprediction of stars at the AGB bump
luminosity. While line diagnostics alone provide only mild constraints on the
cluster age (ruling-out ages younger than ~2 Gyr), when theoretical IL B-V
colors are combined with metallicity derived from the Fe I lines, the age is
constrained to 10--15 Gyr and we obtain [Fe/H]=-0.70 +/-0.021 +/-0.052 dex. We
find that Fe I line diagnostics may also be used to constrain the horizontal
branch morphology of an unresolved cluster. Lastly, our spectrum synthesis of
5.4 million TiO lines indicates that the 7300-7600A TiO window should be useful
for estimating the effect of M giants on the IL abundances, and important for
clusters more metal-rich than 47 Tuc.


title: Natural extension of the Generalised Uncertainty Principle

abstract:
  We discuss a gedanken experiment for the simultaneous measurement of the
position and momentum of a particle in de Sitter spacetime. We propose an
extension of the so-called generalized uncertainty principle (GUP) which
implies the existence of a minimum observable momentum. The new GUP is directly
connected to the nonzero cosmological constant, which becomes a necessary
ingredient for a more complete picture of the quantum spacetime.


title: The velocity distribution of SDSS satellites in MOND

abstract:
  The recent SDSS measured velocity distribution of satellite galaxies has been
modelled in the context of MOND. We show that even when the extra constraint of
adhering to the projected satellite number density profile is added, the two
line of sight (los) velocity dispersion profiles presented in Klypin & Prada
(2007) can be matched simply with a radially varying anisotropy. Interestingly,
the anisotropies required to fit the los velocity dispersions are remarkably
similar to the anisotropies generated by dissipationless collapse simulations
in MOND. The mass-to-light ratios of the two host galaxies used are sensible
and positivity of the distribution function is satisfied.


title: Enabling Rapid Development of Parallel Tree Search Applications

abstract:
  Virtual observatories will give astronomers easy access to an unprecedented
amount of data. Extracting scientific knowledge from these data will
increasingly demand both efficient algorithms as well as the power of parallel
computers. Nearly all efficient analyses of large astronomical datasets use
trees as their fundamental data structure. Writing efficient tree-based
techniques, a task that is time-consuming even on single-processor computers,
is exceedingly cumbersome on massively parallel platforms (MPPs). Most
applications that run on MPPs are simulation codes, since the expense of
developing them is offset by the fact that they will be used for many years by
many researchers. In contrast, data analysis codes change far more rapidly, are
often unique to individual researchers, and therefore accommodate little reuse.
Consequently, the economics of the current high-performance computing
development paradigm for MPPs does not favor data analysis applications. We
have therefore built a library, called Ntropy, that provides a flexible,
extensible, and easy-to-use way of developing tree-based data analysis
algorithms for both serial and parallel platforms. Our experience has shown
that not only does our library save development time, it can also deliver
excellent serial performance and parallel scalability. Furthermore, Ntropy
makes it easy for an astronomer with little or no parallel programming
experience to quickly scale their application to a distributed multiprocessor
environment. By minimizing development time for efficient and scalable data
analysis, we enable wide-scale knowledge discovery on massive datasets.


title: Apery limits and special values of L-functions

abstract:
  We describe a general method to determine the Apery limits of a differential
equation that have a modular-function origin. As a by-product of our analysis,
we discover a family of identities involving the special values of L-functions
associated with modular forms. The proof of these identities is independent of
differential equations and Apery limits.


title:
Time lags in Narrow-line Seyfert 1 galaxies and the origin of their soft
  excess emission

abstract:
  The origin of soft X-ray excess emission from type 1 active galactic nuclei
has remained a major problem for the last two decades. It has not been possible
to distinguish alternative models for the soft excess emission despite the
excellent data quality provided by XMM-Newton and Chandra. Here we present
observations of time lags between the soft and hard band X-ray emission and
discuss the implications to the models for the soft excess. We also device a
method to distinguish the models for the soft excess using Suzaku's broadband
capability.


title: Some new directions in p-adic Hodge theory

abstract:
  We recall some basic constructions from p-adic Hodge theory, then describe
some recent results in the subject. We chiefly discuss the notion of B-pairs,
introduced recently by Berger, which provides a natural enlargement of the
category of p-adic Galois representations. (This enlargement, in a different
form, figures in recent work of Colmez, Bellaiche, and Chenevier on trianguline
representations.) We also discuss results of Liu that indicate that the
formalism of Galois cohomology, including Tate local duality, extends to
B-pairs.


title: A combinatorial approach to functorial quantum sl(k) knot invariants

abstract:
  This paper contains a categorification of the sl(k) link invariant using
parabolic singular blocks of category O. Our approach is intended to be as
elementary as possible, providing combinatorial proofs of the main results of
Sussan. We first construct an exact functor valued invariant of webs or
'special' trivalent graphs labelled with 1, 2, k-1, k satisfying the MOY
relations. Afterwards we extend it to the sl(k)-invariant of links by passing
to the derived categories. The approach using foams appears naturally in this
context. More generally, we expect that our approach provides a representation
theoretic interpretation of the sl(k)-homology, based on foams and the
Kapustin-Lie formula. Conjecturally this implies that the Khovanov-Rozansky
link homology is obtained from our invariant by restriction.


title:
The Effect of the Interstellar Model on Star Formation Properties in
  Galactic Disks

abstract:
  We studied the effect of interstellar gas conditions on global galaxy
simulations by considering three different models for the ISM. Our first model
included only radiative cooling down to 300 K, our second model added an
additional background heating term due to photoelectric heating, and our third
model uses an isothermal equation of state with a temperature of 10^4 K and no
explicit heating or cooling. Two common prescriptions for star formation are
implemented in each case. The first is based on cosmological simulations with a
low threshold for star formation but also a low efficiency. The second assumes
stars form only in high density regions but with a higher efficiency. We also
explore the effects of including feedback from type II supernovae. We find that
the different ISM types produce marked differences in the structure of the disk
and temperature phases present in the gas, although inclusion of feedback
largely dominates these effects. In particular, size of the star-forming clumps
was increased both by background heating and by enforcing an isothermal ISM. We
also looked at the one dimensional profiles and found that a lognormal PDF
provides a good fit for all our simulations over several orders of magnitude in
density. Overall, despite noticeable structural differences, the star formation
properties in the disk are largely insensitive to ISM type and agree reasonably
well with observations.


title: Density of states of helium droplets

abstract:
  Accurate analytical expressions for the state densities of liquid He-4
droplets are derived, incorporating the ripplon and phonon degrees of freedom.
The microcanonical temperature and the ripplon angular momentum level density
are also evaluated. The approach is based on inversions and systematic
expansions of canonical thermodynamic properties.


title: Proper holomorphic mappings in the special class of Reinhardt domains

abstract:
  A complete characterization of proper holomorphic mappings between domains
from the class of all pseudoconvex Reinhardt domains in $\C^2$ with the
logarithmic image equal to a strip or a half-plane is given.


title:
Universal local parametrizations via heat kernels and eigenfunctions of
  the Laplacian

abstract:
  We use heat kernels or eigenfunctions of the Laplacian to construct local
coordinates on large classes of Euclidean domains and Riemannian manifolds (not
necessarily smooth, e.g. with $\mathcal{C}^\alpha$ metric). These coordinates
are bi-Lipschitz on embedded balls of the domain or manifold, with distortion
constants that depend only on natural geometric properties of the domain or
manifold. The proof of these results relies on estimates, from above and below,
for the heat kernel and its gradient, as well as for the eigenfunctions of the
Laplacian and their gradient. These estimates hold in the non-smooth category,
and are stable with respect to perturbations within this category. Finally,
these coordinate systems are intrinsic and efficiently computable, and are of
value in applications.


title:
Fluctuations in Nonequilibrium Statistical Mechanics: Models,
  Mathematical Theory, Physical Mechanisms

abstract:
  The fluctuations in nonequilibrium systems are under intense theoretical and
experimental investigation. Topical ``fluctuation relations'' describe
symmetries of the statistical properties of certain observables, in a variety
of models and phenomena. They have been derived in deterministic and, later, in
stochastic frameworks. Other results first obtained for stochastic processes,
and later considered in deterministic dynamics, describe the temporal evolution
of fluctuations. The field has grown beyond expectation: research works and
different perspectives are proposed at an ever faster pace. Indeed,
understanding fluctuations is important for the emerging theory of
nonequilibrium phenomena, as well as for applications, such as those of
nanotechnological and biophysical interest. However, the links among the
different approaches and the limitations of these approaches are not fully
understood. We focus on these issues, providing: a) analysis of the theoretical
models; b) discussion of the rigorous mathematical results; c) identification
of the physical mechanisms underlying the validity of the theoretical
predictions, for a wide range of phenomena.


title: Factorial ratios, hypergeometric series, and a family of step functions

abstract:
  We give a complete classification of a certain family of step functions
related to the Nyman--Beurling approach to the Riemann hypothesis and
previously studied by V. I. Vasyunin. Equivalently, we completely describe when
certain sequences of ratios of factorial products are always integral.
Essentially, once certain observations are made, this comes down to an
application of Beukers and Heckman's classification of the monodromy of the
hypergeometric function nF_{n-1}. We also note applications to the
classification of cyclic quotient singularities.


title: On proofs of certain combinatorial identities

abstract:
  In this paper we formulate combinatorial identities that give representation
of positive integers as linear combination of even powers of 2 with binomial
coefficients. We present side by side combinatorial as well as computer
generated proofs using the Wilf-Zeilberger(WZ) method.


title: K3 surfaces of finite height over finite fields

abstract:
  Arithmetic of K3 surfaces defined over finite fields is investigated. In
particular, we show that any K3 surface of finite height over a finite field k
of characteristic p > 3 has a quasi-canonical lifting to characteristic 0, and
that for any such lifting, the endormorphism algebra of the transcendental
cycles, as a Hodge module, is a CM field. The Tate conjecture for the product
of certain two K3 surfaces is also proved. We illustrate by examples how to
determine explicitly the formal Brauer group associated to a K3 surface over k.
Examples discussed here are all of hypergeometric type.


title: Probing Non-Standard Neutrino Interactions with Neutrino Factories

abstract:
  We discuss the sensitivity reach of a neutrino factory measurement to
non-standard neutrino interactions (NSI), which may exist as a low-energy
manifestation of physics beyond the Standard Model. We use the muon appearance
mode \nu_e --> \nu_\mu and consider two detectors, one at 3000 km and the other
at 7000 km.
  Assuming the effects of NSI at the production and the detection are
negligible, we discuss the sensitivities to NSI and the simultaneous
determination of \theta_{13} and \delta by examining the effects in the
neutrino propagation of various systems in which two NSI parameters
\epsilon_{\alpha \beta} are switched on. The sensitivities to off-diagonal
\epsilon's are found to be excellent up to small values of \theta_{13}.
  We demonstrate that the two-detector setting is powerful enough to resolve
the \theta_{13}-NSI confusion problem. We believe that the results obtained in
this paper open the door to the possibility of using neutrino factory as a
discovery machine for NSI while keeping its primary function of performing
precision measurements of the lepton mixing parameters.


title:
Street-based Topological Representations and Analyses for Predicting
  Traffic Flow in GIS

abstract:
  It is well received in the space syntax community that traffic flow is
significantly correlated to a morphological property of streets, which are
represented by axial lines, forming a so called axial map. The correlation
co-efficient (R square value) approaches 0.8 and even a higher value according
to the space syntax literature. In this paper, we study the same issue using
the Hong Kong street network and the Hong Kong Annual Average Daily Traffic
(AADT) datasets, and find surprisingly that street-based topological
representations (or street-street topologies) tend to be better representations
than the axial map. In other words, vehicle flow is correlated to a
morphological property of streets better than that of axial lines. Based on the
finding, we suggest the street-based topological representations as an
alternative GIS representation, and the topological analyses as a new
analytical means for geographic knowledge discovery.


title: Entanglement detection via condition of quantum correlation

abstract:
  We develop a novel necessary condition of quantum correlation. It is utilized
to construct $d$-level bipartite Bell-type inequality which is strongly
resistant to noise and requires only analyses of $O(d)$ measurement outcomes
compared to the previous result $O(d^{2})$. Remarkably, a connection between
the arbitrary high-dimensional bipartite Bell-type inequality and entanglement
witnesses is found. Through the necessary condition of quantum correlation, we
propose that the witness operators to detect truly multipartite entanglement
for a generalized Greenberger-Horne-Zeilinger (GHZ) state with two local
measurement settings and a four-qubit singlet state with three settings.
Moreover, we also propose the first robust entanglement witness to detect
four-level tripartite GHZ state with only two local measurement settings.


title:
Improvement on Parameters of Algebraic-Geometry Codes from Hermitian
  Curves

abstract:
  Motivated by Xing's method [7], we show that there exist [n,k,d] linear
Hermitian codes over F_{q^2} with k+d>=n-3 for all sufficiently large q. This
improves the asymptotic bound of Algebraic-Geometry codes from Hermitian curves
given in [9,10].


title:
Constraints on light bending and reflection from the hard X-ray
  background

abstract:
  Light bending due to strong gravity has recently been invoked to explain
variability and flux correlations between different bands in some accreting
black holes. A characteristic feature of light bending is reflection-dominated
spectra, especially if photon sources lie in the deepest parts of the
gravitational potential within a few gravitational radii of the event horizon.
We use the spectrum of the hard X-ray background in order to constrain the
prevalence of such reflection-dominated sources. We first emphasize the need
for reflection and explore the broad-band properties of realistic spectra that
incorporate light bending. We then use these spectra, in conjunction with the
observed 2-10 keV AGN distribution, evolutionary and obscuration functions in
order to predict the hard X-ray background spectrum over 3-100 keV, and provide
limits on the fraction of reflection-dominated objects, dependent on the height
of the photon sources. Our results allow for a cosmologically-significant
fraction of sources that incorporate strong light bending. The luminosity
function based on intrinsic flare luminosities is derived and implications
discussed. We discuss prospects for future hard X-ray missions such as NeXT and
Simbol-X that can image such sources as well as confirm the precise spectral
shape of the background near its peak, important for constraining the universal
relevance of light bending.


title:
On Kummer type construction of supersingular K3 surfaces in
  characteristic 2

abstract:
  We show that every supersingular K3 surface in characteristic 2 with Artin
invariant less than or equal to 2 is obtained by the Kummer type construction
of Schroeer.


title: Quantum phase transition using quantum walks in an optical lattice

abstract:
  We present an approach using quantum walks (QWs) to redistribute ultracold
atoms in an optical lattice. Different density profiles of atoms can be
obtained by exploiting the controllable properties of QWs, such as the variance
and the probability distribution in position space using quantum coin
parameters and engineered noise. The QW evolves the density profile of atoms in
a superposition of position space resulting in a quadratic speedup of the
process of quantum phase transition. We also discuss implementation in
presently available setups of ultracold atoms in optical lattices.


title: Conjugacy, roots, and centralizers in Thompson's group $F$

abstract:
  We complete the program begun by Brin and Squier of characterising conjugacy
in Thompson's group $F$ using the standard action of $F$ as a group of
piecewise linear homeomorphisms of the unit interval.


title:
Study of e+e- --> Lambda anti-Lambda, Lambda anti-Sigma0, Sigma0
  anti-Sigma0 using Initial State Radiation with BABAR

abstract:
  We study the e+e- --> Lambda anti-Lambda gamma, Lambda anti-Sigma0 gamma,
Sigma0 anti-Sigma0 gamma processes using 230 fb-1 of integrated luminosity
collected by the BABAR detector at e+e- center-of-mass energy of 10.58 GeV.
  From the analysis of the baryon-antibaryon mass spectra the cross sections
for e+e- --> Lambda anti-Lambda, Lambda anti-Sigma0, Sigma0 anti-Sigma0 are
measured in the dibaryon mass range from threshold up to 3 GeV/c^2. The ratio
of electric and magnetic form factors, |G_E/G_M|, is measured for e+e- -->
Lambda anti-Lambda, and limits on the relative phase between Lambda form
factors are obtained. We also measure the J/psi --> Lambda anti-Lambda, Sigma0
anti-Sigma0 and psi(2S) --> Lambda anti-Lambda branching fractions.


title:
Influence of Mg Deficiency on the Superconductivity in MgB2 Thin Films
  Grown by using HPCVD

abstract:
  The effects of Mg deficiency in MgB2 films grown by using hybrid
physical-chemical vapor deposition were investigated after vacuum annealing at
various temperatures. High-quality MgB2 films grown on c-cut Al2O3 substrates
with different superconducting transition temperatures (Tc) of 40.2 and 41 K
were used in this study. As the annealing temperature was increased from 200 to
800 C, the Mg contents in the MgB2 films systemically decreased, but the Tc's
did not change, within 0.12 K, until the annealing temperature reached 700 C.
For MgB2 films annealed at 800 C for 30 min, however, no superconductivity was
observed, and the temperature dependence of the resistivity showed a
semiconducting behavior. We also found that the residual resistivity ratio
decreased with increasing annealing temperature.


title: An ATCA 20cm Radio Continuum Study of the Large Magellanic Cloud

abstract:
  We present a mosaic image of the 1.4GHz radio continuum emission from the
Large Magellanic Cloud (LMC) observed with the Australia Telescope Compact
Array (ATCA) and the Parkes Telescope. The mosaic covers 10.8 x 12.3 square
degrees with an angular resolution of 40", corresponding to a spatial scale of
10pc in the LMC. The final image is suitable for studying emission on all
scales between 40" and the surveyed area. In this paper, we discuss i) the
characteristics of the LMC's diffuse and compact radio continuum emission, ii)
the fraction of the emission produced by thermal processes and the implied star
formation rate in the LMC, and iii) variations in the radio spectral index
across the LMC. Two non-standard reduction techniques that we used to process
the ATCA visibility data may be of interest for future wide-field radio
continuum surveys. The data are open to the astronomical community and should
be a rich resource for studies of individual objects such as supernova
remnants, HII regions and planetary nebulae, as well as extended features such
as the diffuse emission from synchrotron radiation.


title: Dephasing in a quantum dot coupled to a quantum point contact

abstract:
  We investigate a dephasing mechanism in a quantum dot capacitively coupled to
a quantum point contact. We use a model which was proposed to explain the 0.7
structure in point contacts, based on the presence of a quasi-bound state in a
point contact. The dephasing rate is examined in terms of charge fluctuations
of electrons in the bound state. We address a recent experiment by
Avinun-Kalish {\it et al.} [Phys. Rev. Lett. {\bf 92}, 156801 (2004)], where a
double peak structure appears in the suppressed conductance through the quantum
dot. We show that the two conducting channels induced by the bound state are
responsible for the peak structure.


title: Microlensing Detections of Planets in Binary Stellar Systems

abstract:
  We demonstrate that microlensing can be used for detecting planets in binary
stellar systems. This is possible because in the geometry of planetary binary
systems where the planet orbits one of the binary component and the other
binary star is located at a large distance, both planet and secondary companion
produce perturbations at a common region around the planet-hosting binary star
and thus the signatures of both planet and binary companion can be detected in
the light curves of high-magnification lensing events. We find that identifying
planets in binary systems is optimized when the secondary is located in a
certain range which depends on the type of the planet. The proposed method can
detect planets with masses down to one tenth of the Jupiter mass in binaries
with separations <~ 100 AU. These ranges of planet mass and binary separation
are not covered by other methods and thus microlensing would be able to make
the planetary binary sample richer.


title: The formation of young B/PS bulges in edge-on barred galaxies

abstract:
  We report about the fact that the stellar population that is born in the gas
inflowing towards the central regions can be vertically unstable leading to a
B/PS feature remarkably bluer that the surrounding bulge. Using new
chemodynamical simulations we show that this young population does not remain
as flat as the gaseous nuclear disc and buckles out of the plane to form a new
boxy bulge. We show that such a young B/PS bulge can be detected in colour
maps.


title: Generalized solutions to nonlinear first order Cauchy problems

abstract:
  The recent significant enrichment of the Order Completion Method for
nonlinear Systems of PDEs resulted in the global existence of generalized
solutions to a large class of such equations. In this paper we investigate the
existence and regularity of the generalized solutions to a family of nonlinear
first order Cauchy problems. The spaces of generalized solutions are obtained
as the completions of suitably constructed uniform convergence spaces.


title:
The Physics of Bodily Tides in Terrestrial Planets, and the Appropriate
  Scales of Dynamical Evolution

abstract:
  Any model of tides is based on a specific hypothesis of how lagging depends
on the tidal-flexure frequency. For example, Gerstenkorn (1955), MacDonald
(1964), and Kaula (1964) assumed constancy of the geometric lag angle, while
Singer (1968) and Mignard (1979, 1980) asserted constancy of the time lag.
Thus, each of these two models was based on a certain law of scaling of the
geometric lag.
  The actual dependence of the geometric lag on the frequency is more
complicated and is determined by the rheology of the planet. Besides, each
particular functional form of this dependence will unambiguously fix the
appropriate form of the frequency dependence of the tidal quality factor, Q.
Since at present we know the shape of the dependence of Q upon the frequency,
we can reverse our line of reasoning and single out the appropriate actual
frequency-dependence of the angular lag. This dependence turns out to be
different from those employed hitherto, and it entails considerable alterations
in the time scales of the tide-generated dynamical evolution. Phobos' fall on
Mars is an example we consider.


title:
$x-$dependence of the quark distribution functions in the
  $\chi$CQM$_{{\rm config}}$

abstract:
  Chiral constituent quark model with configuration mixing (\chiCQM_{{\rm
config}}) is known to provide a satisfactory explanation of the ``proton spin
problem'' and related issues. In order to enlarge the scope of \chiCQM_{{\rm
config}}, we have attempted to phenomenologically incorporate x-dependence in
the quark distribution functions. In particular, apart from calculating valence
and sea quark distributions q_{{\rm val}}(x) and \bar q(x), we have carried out
a detailed analysis to estimate the sea quark asymmetries \bar d(x)-\bar u(x),
\bar d(x)/\bar u(x) and \frac{\bar d(x)-\bar u(x)}{u(x)-d(x)} as well as spin
independent structure functions F_2^p(x)-F_2^n(x) and $F_2^n(x)/F_2^p(x)$ as
functions of $x$. We are able to achieve a satisfactory fit for all the above
mentioned quantities simultaneously. The inclusion of effects due to
configuration mixing have also been examined in the case F_2^p(x)-F_2^n(x) and
F_2^n(x)/F_2^p(x) where the valence quark distributions dominate and it is
found that it leads to considerable improvement in the results. Further, the
valence quark structure has also be tested by extrapolating the predictions of
our model in the limit x \to 1 where data is not available.


title:
Convergent Iterative Solutions of Schroedinger Equation for a
  Generalized Double Well Potential

abstract:
  We present an explicit convergent iterative solution for the lowest energy
state of the Schroedinger equation with a generalized double well potential
$V=\frac{g^2}{2}(x^2-1)^2(x^2+a)$. The condition for the convergence of the
iteration procedure and the dependence of the shape of the groundstate wave
function on the parameter $a$ are discussed.


abstract:
  The theory of internal waves between two layers of immiscible fluids is
important both for its applications in oceanography and engineering, and as a
source of interesting mathematical model equations that exhibit nonlinearity
and dispersion. A Boussinesq system for two-way propagation of interfacial
waves in a rigid lid configuration is derived. In most cases, the nonlinearity
is quadratic. However, when the square of the depth ratio is close to the
density ratio, the coefficients of the quadratic nonlinearities become small
and cubic nonlinearities must be considered. The propagation as well as the
collision of solitary waves and/or fronts is studied numerically.


title: An extension of Wick's theorem

abstract:
  We propose an extension of a result by Repetowicz et al. about Wick's theorem
and its applications: we first show that Wick's theorem can be extended to the
uniform distribution on the sphere and then to the whole class of elliptical
distributions. Then, as a special case, we detail this result for distributions
that are Gaussian scale mixtures. Finally, we show that these results allow to
recover easily a theorem by Folland about integration of polynomials over the
sphere.


title:
The geometry of fractional osculator bundle of higher order and
  applications

abstract:
  Using the reviewed Riemann-Liouville fractional derivative we introduce the
fractional osculator Lagrange space of k order and the main structures on it.
The results are applied at the k order fractional prolongation of Lagrange,
Finsler and Riemann fractional structures.


title: Sign changes of coefficients of half integral weight modular forms

abstract:
  For a half integral weight modular form $f$ we study the signs of the Fourier
coefficients $a(n)$. If $f$ is a Hecke eigenform of level $ N$ with real
Nebentypus character, and $t$ is a fixed square-free positive integer with
$a(t)\neq 0$, we show that for all but finitely many primes $p$ the sequence
$(a(tp^{2m}))_{m}$ has infinitely many signs changes. Moreover, we prove
similar (partly conditional) results for arbitrary cusp forms $f$ which are not
necessarily Hecke eigenforms.


title:
$SLE(\kappa,\rho)$ processes, hiding exponents and self-avoiding walks
  in a wedge

abstract:
  This article employs Schramm-Loewner Evolution to obtain intersection
exponents for several chordal $SLE_{8/3}$ curves in a wedge. As $SLE_{8/3}$ is
believed to describe the continuum limit of self-avoiding walks, these
exponents correspond to those obtained by Cardy, Duplantier and Saleur for
self-avoiding walks in an arbitrary wedge-shaped geometry using conformal
invariance based arguments. Our approach builds on work by Werner, where the
restriction property for $SLE(\kappa,\rho)$ processes and an absolute
continuity relation allow the calculation of such exponents in the half-plane.
Furthermore, the method by which these results are extended is general enough
to apply to the new class of hiding exponents introduced by Werner.


title: On rate optimality for ill-posed inverse problems in econometrics

abstract:
  In this paper, we clarify the relations between the existing sets of
regularity conditions for convergence rates of nonparametric indirect
regression (NPIR) and nonparametric instrumental variables (NPIV) regression
models. We establish minimax risk lower bounds in mean integrated squared error
loss for the NPIR and the NPIV models under two basic regularity conditions
that allow for both mildly ill-posed and severely ill-posed cases. We show that
both a simple projection estimator for the NPIR model, and a sieve minimum
distance estimator for the NPIV model, can achieve the minimax risk lower
bounds, and are rate-optimal uniformly over a large class of structure
functions, allowing for mildly ill-posed and severely ill-posed cases.


title:
Bright Solitary-Matter-Wave Collisions in a Harmonic Trap: Regimes of
  Soliton-like Behaviour

abstract:
  Systems of solitary-waves in the 1D Gross-Pitaevskii equation, which models a
trapped atomic Bose-Einstein condensate, are investigated theoretically. To
analyse the soliton-like nature of these solitary-waves, a particle analogy for
the solitary-waves is formulated. Exact soliton solutions exist in the absence
of an external trapping potential, which behave in a particle-like manner, and
we find the particle analogy we employ to be a good model also when a harmonic
trapping potential is present. In the case of two solitons, the particle model
is integrable, and the dynamics are completely regular. The extension to three
particles supports chaotic regimes. The agreement between the particle model
and the wave dynamics remains good even in chaotic regimes. In the case of a
system of two solitary waves of equal norm, the solitons are shown to retain
their phase difference for repeated collisions. This implies that soliton-like
regimes may be found in 3D geometries where solitary waves can be made to
repeatedly collide out of phase, stabilising the condensate against collapse.


title: Divergence of effective mass in 'Uncorrelated State Percolation' Model

abstract:
  We want to answer the question of whether the divergence in the effective
mass in metal-insulator transition (MIT) in 2DEG is in the same universality
class as percolation. We use a model to make Percolated state in 2D and then
calculate the effective mass in a super-cell and the Bloch Theorem. It is seen
that the effective mass, m*, scales as m*~(P-Pc)^a with a=1 and Pc being the
(classical) percolation threshold.


title:
The role of rotation on Petersen Diagrams. II The influence of
  near-degeneracy

abstract:
  In the present work, the effect of near-degeneracy on rotational Petersen
diagrams (RPD) is analysed. Seismic models are computed considering rotation
effects on both equilibrium models and adiabatic oscillation frequencies
(including second-order near-degeneracy effects). Contamination of coupled
modes and coupling strength on the first radial modes are studied in detail.
Analysis of relative intrinsic amplitudes of near-degenerate modes reveals that
the identity of the fundamental radial mode and its coupled quadrupole pair are
almost unaltered once near-degeneracy effects are considered. However, for the
first overtone, a mixed radial/quadrupole identity is always predicted. The
effect of near-degeneracy on the oscillation frequencies becomes critical for
rotational velocities larger than 15-20 km/s, for which large wriggles in the
evolution of the period ratios are obtained (up $10^{-2}$). Such wriggles imply
uncertainties, in terms of metallicity determinations using RPD, reaching up to
0.50 dex, which can be critical for Pop. I HADS (High Amplitude \dss). In terms
of mass determinations, uncertainties reaching up to 0.5 M_sun are predicted.
The location of such wriggles is found to be independent of metallicity and
rotational velocity, and governed mainly by the avoided-crossing phenomenon.


title:
Nonparametric estimation for L\'evy processes from low-frequency
  observations

abstract:
  We suppose that a L\'evy process is observed at discrete time points. A
rather general construction of minimum-distance estimators is shown to give
consistent estimators of the L\'evy-Khinchine characteristics as the number of
observations tends to infinity, keeping the observation distance fixed. For a
specific $C^2$-criterion this estimator is rate-optimal. The connection with
deconvolution and inverse problems is explained. A key step in the proof is a
uniform control on the deviations of the empirical characteristic function on
the whole real line.


title:
Continuity of the radius of convergence of p-adic differential equations
  on Berkovich analytic spaces

abstract:
  We consider a vector bundle with integrable connection (\cE,\na) on an
analytic domain U in the generic fiber \cX_{\eta} of a smooth formal p-adic
scheme \cX, in the sense of Berkovich. We define the \emph{diameter}
\delta_{\cX}(\xi,U) of U at \xi\in U, the \emph{radius} \rho_{\cX}(\xi) of the
point \xi\in\cX_{\eta}, the \emph{radius of convergence} of solutions of
(\cE,\na) at \xi, R(\xi) = R_{\cX}(\xi, U,(\cE, \na)). We discuss (semi-)
continuity of these functions with respect to the Berkovich topology. In
particular, under we prove under certain assumptions that \delta_{\cX}(\xi,U),
\rho_{\cX}(\xi) and R_{\xi}(U,\cE,\na) are upper semicontinuous functions of
\xi; for Laurent domains in the affine space, \delta_{\cX}(-,U) is continuous.
In the classical case of an affinoid domain U of the analytic affine line, R is
a continuous function.


title:
Emergence of Network Structure in Models of Collective Evolution and
  Evolutionary Dynamics

abstract:
  We consider an evolving network of a fixed number of nodes. The allocation of
edges is a dynamical stochastic process inspired by biological reproduction
dynamics, namely by deleting and duplicating existing nodes and their edges.
The properties of the degree distribution in the stationary state is analysed
by use of the Fokker-Planck equation. For a broad range of parameters
exponential degree distributions are observed. The mechanism responsible for
this behaviour is illuminated by use of a simple mean field equation and
reproduced by the Fokker-Planck equation treating the degree-degree
correlations approximately. In the limit of zero mutations the degree
distribution becomes a power law.


title: Maximal Entropy Measures for Piecewise Affine Surface Homeomorphisms

abstract:
  We study the dynamics of piecewise affine surface homeomorphisms from the
point of view of their entropy. Under the assumption of positive topological
entropy, we establish the existence of finitely many ergodic and invariant
probability measures maximizing entropy and prove a multiplicative lower bound
for the number of periodic points. This is intended as a step towards the
understanding of surface diffeomorphisms. We proceed by building a jump
transformation, using not first returns but carefully selected "good" returns
to dispense with Markov partitions. We control these good returns through some
entropy and ergodic arguments.


title: Highly non-Gaussian states created via cross-Kerr nonlinearity

abstract:
  We propose a feasible scheme for generation of strongly non-Gaussian states
using the cross-Kerr nonlinearity. The resultant states are highly
non-classical states of electromagnetic field and exhibit negativity of their
Wigner function, sub-Poissonian photon statistics, and amplitude squeezing.
Furthermore, the Wigner function has a distinctly pronounced ``banana'' or
``crescent'' shape specific for the Kerr-type interactions, which so far was
not demonstrated experimentally. We show that creating and detecting such
states should be possible with the present technology using electromagnetically
induced transparency in a four-level atomic system in N-configuration.


title: Simulation of LiCAS Error Propagation

abstract:
  Linear Collider Alignment and Survey (LiCAS) R&D group is proposing a novel
automated metrology instrument dedicated to align and monitor the mechanical
stability of a future linear high energy e+e- collider. LiCAS uses Laser
Straightness Monitors (LSM) and Frequency Scanning Interferometry (FSI) for
straightness and absolute distance measurements, respectively. This paper
presents detailed simulations of a LiCAS system operating inside a Rapid Tunnel
Reference Surveyor (RTRS train). With the proposed design it is feasible to
achieve the required vertical accuracy of the order of 200 micons over 600 m
tunnel sections meeting the specification for the TESLA collider.


title:
Equivalence and self-improvement of p-fatness and Hardy's inequality,
  and association with uniform perfectness

abstract:
  We present an easy proof that $p$--Hardy's inequality implies uniform
$p$--fatness of the boundary when $p=n$. The proof works also in metric space
setting and demonstrates the self--improving phenomenon of the $p$--fatness. We
also explore the relationship between $p$-fatness, $p$-Hardy inequality, and
the uniform perfectness for all $p\ge 1$, and demonstrate that in the Ahlfors
$Q$-regular metric measure space setting with $p=Q$, these three properties are
equivalent.


title:
Selfconsistent gauge-invariant theory of in-plane infrared response of
  high-Tc cuprate superconductors involving spin fluctuations

abstract:
  We report on results of our theoretical study of the in-plane infrared
conductivity of the high-Tc cuprate superconductors using the model where
charged planar quasiparticles are coupled to spin fluctuations. The
computations include both the renormalization of the quasiparticles and the
corresponding modification of the current-current vertex function (vertex
correction), which ensures gauge invariance of the theory and local charge
conservation in the system. The incorporation of the vertex corrections leads
to an increase of the total intraband optical spectral weight (SW) at finite
frequencies, a SW transfer from far infrared to mid infrared, a significant
reduction of the SW of the superconducting condensate, and an amplification of
characteristic features in the superconducting state spectra of the inverse
scattering rate 1/tau. We also discuss the role of selfconsistency and propose
a new interpretation of a kink occurring in the experimental low temperature
spectra of 1/tau around 1000cm^{-1}.


title:
Complexity, Collective Effects and Modelling of Ecosystems: formation,
  function and stability

abstract:
  We discuss the relevance of studying ecology within the framework of
Complexity Science from a statistical mechanics approach. Ecology is concerned
with understanding how systems level properties emerge out of the multitude of
interactions amongst large numbers of components, leading to ecosystems that
possess the prototypical characteristics of complex systems. We argue that
statistical mechanics is at present the best methodology available to obtain a
quantitative description of complex systems, and that ecology is in urgent need
of ``integrative'' approaches that are quantitative and non-stationary. We
describe examples where combining statistical mechanics and ecology has led to
improved ecological modelling and, at the same time, broadened the scope of
statistical mechanics.


title: Distribution of PageRank Mass Among Principle Components of the Web

abstract:
  We study the PageRank mass of principal components in a bow-tie Web Graph, as
a function of the damping factor c. Using a singular perturbation approach, we
show that the PageRank share of IN and SCC components remains high even for
very large values of the damping factor, in spite of the fact that it drops to
zero when c goes to one. However, a detailed study of the OUT component reveals
the presence ``dead-ends'' (small groups of pages linking only to each other)
that receive an unfairly high ranking when c is close to one. We argue that
this problem can be mitigated by choosing c as small as 1/2.


title:
Closed trajectories of a particle model on null curves in anti-de Sitter
  3-space

abstract:
  We study the existence of closed trajectories of a particle model on null
curves in anti-de Sitter 3-space defined by a functional which is linear in the
curvature of the particle path. Explicit expressions for the trajectories are
found and the existence of infinitely many closed trajectories is proved.


title:
On conversion of high-frequency soliton solutions to a (1+1)-dimensional
  nonlinear evolution equation

abstract:
  We derive a (1+1)-dimensional nonlinear evolution equation (NLE) which may
model the propagation of high-frequency perturbations in a relaxing medium. As
a result, this equation may possess three typical solutions depending on a
dissipative parameter.


title: Drift Wave Model of Rotating Radio Transients

abstract:
  During the last few years there were discovered and deeply examined several
transient neutron stars (Rotating Radio Transients). It is already well
accepted that these objects are rotating neutron stars. But their extraordinary
features (burst-like behavior) made necessary revision of well accepted models
of pulsar interior structure. Nowadays most popular model for RRATs is
precessing pulsar model, which is the subject of big discussion. We assume that
these objects are pulsars with specific spin parameters. An important feature
of our model, naturally explaining most of the properties of these neutron
stars, is presence of very low frequency, nearly transverse drift waves
propagating across the magnetic field and encircling the open field lines
region of the pulsar magnetosphere.


title: Precise quark masses from sum rules

abstract:
  In this contribution an improved analysis is described to extract precise
charm and bottom quark masses from experimental and theoretical moments of the
photon polarization function. The obtained $\bar{\rm MS}$ mass values read
$m_c(3 {GeV})=0.986(13)$ GeV and $m_b(10 {GeV})=3.609(25)$ GeV.


title: A Clark-Ocone formula in UMD Banach spaces

abstract:
  Let H be a separable real Hilbert space and let F = (F_t)_{t\in [0,T]} be the
augmented filtration generated by an H-cylindrical Brownian motion W_H on
[0,T]. We prove that if E is a UMD Banach space, 1\leq p<\infty, and f\in
D^{1,p}(E) is F_T-measurable, then f = \E f + \int_0^T P_F(Df) dW_H where D is
the Malliavin derivative and P_F is the projection onto the F-adapted elements
in a suitable Banach space of L^p-stochastically integrable L(H,E)-valued
processes.


title: Tunneling mediated by conical waves in a 1D lattice

abstract:
  The nonlinear propagation of 3D wave-packets in a 1D Bragg-induced band-gap
system, shows that tranverse effects (free space diffraction) affect the
interplay of periodicity and nonlinearity, leading to the spontaneous formation
of fast and slow conical localized waves. Such excitation corresponds to
enhanced nonlinear transmission (tunneling) in the gap, with peculiar features
which differ on the two edges of the band-gap, as dictated by the full
dispersion relationship of the localized waves.


title: Biharmonic Hypersurfaces in 4-Dimensional Space Forms

abstract:
  We investigate proper biharmonic hypersurfaces with at most three distinct
principal curvatures in space forms. We obtain the full classification of
proper biharmonic hypersurfaces in 4-dimensional space forms.


title:
Smooth cutoff formulation of hierarchical reference theory for a scalar
  phi4 field theory

abstract:
  The phi4 scalar field theory in three dimensions, prototype for the study of
phase transitions, is investigated by means of the hierarchical reference
theory (HRT) in its smooth cutoff formulation. The critical behavior is
described by scaling laws and critical exponents which compare favorably with
the known values of the Ising universality class. The inverse susceptibility
vanishes identically inside the coexistence curve, providing a first principle
implementation of the Maxwell construction, and shows the expected
discontinuity across the phase boundary, at variance with the usual sharp
cutoff implementation of HRT. The correct description of first and second order
phase transitions within a microscopic, nonperturbative approach is thus
achieved in the smooth cutoff HRT.


title:
Origin of the Ocean on the Earth: Early Evolution of Water D/H in a
  Hydrogen-rich Atmosphere

abstract:
  The origin of the Earth's ocean has been discussed on the basis of
deuterium/hydrogen ratios (D/H) of several sources of water in the solar
system. The average D/H of carbonaceous chondrites (CC's) is known to be close
to the current D/H of the Earth's ocean, while those of comets and the solar
nebula are larger by about a factor of two and smaller by about a factor of
seven, respectively, than that of the Earth's ocean. Thus, the main source of
the Earth's ocean has been thought to be CC's or adequate mixing of comets and
the solar nebula. However, those conclusions are correct only if D/H of water
on the Earth has remained unchanged for the past 4.5 Gyr. In this paper, we
investigate evolution of D/H in the ocean in the case that the early Earth had
a hydrogen-rich atmosphere, the existence of which is predicted by recent
theories of planet formation no matter whether the nebula remains or not. Then
we show that D/H in the ocean increases by a factor of 2-9, which is caused by
the mass fractionation during atmospheric hydrogen loss, followed by deuterium
exchange between hydrogen gas and water vapor during ocean formation. This
result suggests that the apparent similarity in D/H of water between CC's and
the current Earth's ocean does not necessarily support the CC's origin of water
and that the apparent discrepancy in D/H is not a good reason for excluding the
nebular origin of water.


title: Surface branched covers and geometric 2-orbifolds

abstract:
  For a branched cover between two closed orientable surfaces, the
Riemann-Hurwitz formula relates the Euler characteristics of the surfaces, the
total degree of the cover, and the total length of the partitions of the degree
given by the local degrees at the preimages of the branching points. A very old
problem asks whether a collection of partitions of an integer having the
appropriate total length (that we call a candidate cover) always comes from
some branched cover. The answer is known to be in the affirmative whenever the
candidate base surface is not the 2-sphere, while for the 2-sphere exceptions
do occur. A long-standing conjecture however asserts that when the candidate
degree is a prime number, a candidate cover is always realizable. In this paper
we analyze the question from the point of view of the geometry of 2-orbifolds,
and we provide strong supporting evidence for the conjecture. In particular, we
exhibit three different sequences of candidate covers, indexed by their degree,
such that for each sequence: (1) The degrees giving realizable covers have
asymptotically zero density in the naturals; (2) Each prime degree gives a
realizable cover.


title: Units of genetic transfer in prokaryotes

abstract:
  The transfer of genetic materials across species (lateral genetic transfer,
LGT) contributes to genomic and physiological innovation in prokaryotes. The
extent of LGT in prokaryotes has been examined in a number of studies, but the
unit of transfer has not been studied in a rigorous manner. Using a rigorous
phylogenetic approach, we analysed the units of LGT within families of
single-copy genes obtained from 144 fully sequenced prokaryote genomes. A total
of 30.3% of these gene families show evidence of LGT. We found that the
transfer of gene fragments has been more frequent than the transfer of entire
genes, suggesting the extent of LGT has been underestimated. We found little
functional bias between within-gene (fragmentary) and whole-gene
(non-fragmentary) genetic transfer, but non-fragmentary transfer has been more
frequent into pathogens than into non-pathogens. As gene families that contain
probable paralogs were excluded from the current study, our results may still
underestimate the extent of LGT; nonetheless this is the most-comprehensive
study to date of the unit of LGT among prokaryote genomes.


title:
Angular Momemtum of Binary Asteroids: Implication for their possible
  origin

abstract:
  We describe in this work a thorough study of the physical and orbital
characteristics of extensively observed main-belt and Trojan binaries, mainly
taken from the LAOSA (Large Adaptive Optics Survey of Asteroids, Marchis et
al., 2006c) database, along with a selection of bifurcated objects.
Dimensionless quantities, such as the specific angular momentum and the primary
spin rate, are computed and discussed for each system. They suggest that these
asteroidal systems might be the outcome of rotational fission or mass shedding
of a parent body presumably subjected to an external torque.
  One of the most striking features of separated binaries composed of a large
primary (Rp > 100 km) with a much smaller secondary (Rs < 20 km) is that they
all have total angular momentum of 0.27. This value is quite close to the
Maclaurin-Jacobi bifurcation (0.308) of a spinning fluid body. Alternatively,
contact binaries and tidally locked double asteroids, made of components of
similar size, have an angular momentum larger than 0.48. They compare
successfully with the fission equilibrium sequence of a rotating fluid mass. In
conclusion, we find that total angular momentum is a useful proxy to assess
internal structure of such systems.


title:
Tuning the stochastic background of gravitational waves with theory and
  observations

abstract:
  In this this paper the stochastic background of gravitational waves (SBGWs)
is analyzed with the auxilium of the WMAP data. We emphasize that, in general,
in previous works in the literature about the SBGWs, old COBE data were used.
After this, we want to face the problem of how the SBGWs and f(R) gravity can
be related, showing, vice versa, that a revealed SBGWs could be a powerly probe
for a given theory of gravity. In this way, it will also be shown that the
conformal treatment of SBGWs can be used to parametrize in a natural way f(R)
theories.


title: Protein domains as units of genetic transfer

abstract:
  Genomes evolve as modules. In prokaryotes (and some eukaryotes), genetic
material can be transferred between species and integrated into the genome via
homologous or illegitimate recombination. There is little reason to imagine
that the units of transfer correspond to entire genes; however, such units have
not been rigorously characterized. We examined fragmentary genetic transfers in
single-copy gene families from 144 prokaryotic genomes and found that
breakpoints are located significantly closer to the boundaries of genomic
regions that encode annotated structural domains of proteins than expected by
chance, particularly when recombining sequences are more divergent. This
correlation results from recombination events themselves and not from
differential nucleotide substitution. We report the first systematic study
relating genetic recombination to structural features at the protein level.


title: Genetic transfer in Staphylococcus: a case study of 13 genomes

abstract:
  The widespread presence of antibiotic resistance and virulence among
Staphylococcus isolates has been attributed to lateral genetic transfer (LGT)
between different strains or species. However, there has been very little study
of the extent of LGT in Staphylococcus species using a phylogenetic approach,
particularly of the units of such genetic transfer. Here we report the first
systematic study of the units of genetic transfer in 13 Staphylococcus genomes,
using a rigorous phylogenetic approach. We found clear evidence of LGT in 26.1%
of the 1354 homologous gene families examined, and possibly more in another
17.9% of the total families. Within-gene and whole-gene transfer contribute
almost equally to the discordance of these gene families against a reference
phylogeny. Comparing genetic transfer in single-copy and in multi-copy gene
families, we found little functional bias in cases of within-gene (fragmentary)
genetic transfer but substantial functional bias in cases of whole-gene
(non-fragmentary) genetic transfer, and we observed a higher frequency of LGT
in multi-copy gene families. Our results demonstrate that LGT and gene
duplication play an important part among the factors that contribute to
functional innovation in staphylococcal genomes.


title: Long term monitoring of bright TeV Blazars with the MAGIC telescope

abstract:
  The MAGIC telescope has performed long term monitoring observations of the
bright TeV Blazars Mrk421, Mrk501 and 1ES1959+650. Up to 40 observations, 30 to
60 minutes each have been performed for each source evenly distributed over the
observable period of the year. The sensitivity of MAGIC is sufficient to
establish a flux level of 25% of the Crab flux for each measurement. These
observations are well suited to trigger multiwavelength ToO observations and
the overall collected data allow an unbiased study of the flaring statistics of
the observed AGNs.


title:
Strategy for the inversion of Hinode spectropolarimetric measurements in
  the quiet Sun

abstract:
  In this paper we propose an inversion strategy for the analysis of
spectropolarimetric measurements taken by {\em Hinode} in the quiet Sun. The
spectropolarimeter of the Solar Optical Telescope aboard {\em Hinode} records
the Stokes spectra of the \ion{Fe}{i} line pair at 630.2 nm with unprecendented
angular resolution, high spectral resolution, and high sensitivity. We discuss
the need to consider a {\em local} stray-light contamination to account for the
effects of telescope diffraction. The strategy is applied to observations of a
wide quiet Sun area at disk center. Using these data we examine the influence
of noise and initial guess models in the inversion results. Our analysis yields
the distributions of magnetic field strengths and stray-light factors. They
show that quiet Sun internetwork regions consist mainly of hG fields with
stray-light contaminations of about 0.8.


title: Gradient Optics of subwavelength nanofilms

abstract:
  Propagation and tunneling of light through subwavelength photonic barriers,
formed by dielectric layers with continuous spatial variations of dielectric
susceptibility across the film are considered. Effects of giant
heterogeneity-induced non-local dispersion, both normal and anomalous, are
examined by means of a series of exact analytical solutions of Maxwell
equations for gradient media. Generalized Fresnel formulae, visualizing a
profound influence of gradient and curvature of dielectric susceptibility
profiles on reflectance/transmittance of periodical photonic heterostructures
are presented. Depending on the cutoff frequency of the barrier, governed by
technologically managed spatial profile of its refractive index, propagation or
tunneling of light through these barriers are examined. Nonattenuative transfer
of EM energy by evanescent waves, tunneling through dielectric gradient
barriers, characterized by real values of refractive index, decreasing in the
depth of medium, is shown. Scaling of the obtained results for different
spectral ranges of visible, IR and THz waves is illustrated. Potential of
gradient optical structures for design of miniaturized filters, polarizers and
frequency-selective interfaces of subwavelength thickness is considered.


title:
Coexistence of hexatic and isotropic phases in two-dimensional Yukawa
  systems

abstract:
  We have performed Brownian dynamics simulations on melting of two-dimensional
colloidal crystal in which particles interact with Yukawa potential. The pair
correlation function and bond-orientational correlation function was calculated
in the Yukawa system. An algebraic decay of the bond orientational correlation
function was observed. By ruling out the coexistence region, only a unstable
hexatic phase was found in the Yukawa systems. But our work shows that the
melting of the Yukawa systems is a two-stage melting not consist with the KTHNY
theory and the isotropic liquid and the hexatic phase coexistence region was
found. Also we have studied point defects in two-dimensional Yukawa systems.


title: Construction of covers in positive characteristic via degeneration

abstract:
  In this note we construct examples of covers of the projective line in
positive characteristic such that every specialization is inseparable. The
result illustrates that it is not possible to construct all covers of the
generic r-pointed curve of genus zero inductively from covers with a smaller
number of branch points.


title: Orbifolds versus smooth heterotic compactifications

abstract:
  Following the recent exploration of smooth heterotic compactifications with
unitary bundles, orbifold compactifications in six dimensions can be shown to
correspond in the blow-up to compactifications with U(1) gauge backgrounds. A
powerful tool is the comparison of anomaly polynomials. The presentation here
focuses on heterotic SO(32) compactifications in six dimensions including
five-branes. Four dimensional and E8 x E8 models are briefly commented on.


title:
Nodal points and the transition from ordered to chaotic Bohmian
  trajectories

abstract:
  We explore the transition from order to chaos for the Bohmian trajectories of
a simple quantum system corresponding to the superposition of three stationary
states in a 2D harmonic well with incommensurable frequencies. We study in
particular the role of nodal points in the transition to chaos. Our main
findings are: a) A proof of the existence of bounded domains in configuration
space which are devoid of nodal points, b) An analytical construction of formal
series representing regular orbits in the central domain as well as a numerical
investigation of its limits of applicability. c) A detailed exploration of the
phase-space structure near the nodal point. In this exploration we use an
adiabatic approximation and we draw the flow chart in a moving frame of
reference centered at the nodal point. We demonstrate the existence of a saddle
point (called X-point) in the vicinity of the nodal point which plays a key
role in the manifestation of exponential sensitivity of the orbits. One of the
invariant manifolds of the X-point continues as a spiral terminating at the
nodal point. We find cases of Hopf bifurcation at the nodal point and explore
the associated phase space structure of the nodal point - X-point complex. We
finally demonstrate the mechanism by which this complex generates chaos.
Numerical examples of this mechanism are given for particular chaotic orbits,
and a comparison is made with previous related works in the literature.


title:
Geometrical embeddings for distributions into algebras of generalized
  functions

abstract:
  We use spectral theory to produce embeddings of distributions in the algebras
of generalized functions on a closed Riemannian manifold. These embeddings are
invariant under isometries and preserve the singularity structure of the
distributions.


title:
The RMS Survey: Mid-Infrared Observations of Candidate Massive YSOs in
  the Southern Hemisphere

abstract:
  Abridged abstract: The Red MSX Source (RMS) survey is an ongoing effort to
return a large, well-selected sample of massive young stellar objects (MYSOs)
within our Galaxy. A series of ground-based follow-up observations are being
undertaken in order to remove contaminant objects from our list of 2000
candidates, and to begin characterising these MYSOs. As a part of these
follow-up observations, high resolution (~1") mid-IR imaging aids the
identification of contaminant objects which are resolved (UCHII regions, PN) as
opposed to those which are unresolved (YSOs, evolved stars) as well as
identifying YSOs near UCHII regions and other multiple sources. We present 10.4
micron imaging observations for 346 candidate MYSOs in the RMS survey in the
Southern Hemisphere, primarily outside the region covered by the GLIMPSE
Spitzer Legacy Survey. These were obtained using TIMMI2 on the ESO 3.6m
telescope in La Silla, Chile. Our photometric accuracy is of order 0.05Jy, and
our astrometric accuracy is 0.8", which is an improvement over the nominal 2"
accuracy of the MSX PSC.


title: A note on the quantization of a multi-horizon black hole

abstract:
  We consider the quasinormal spectrum of a charged scalar field in the
(charged) Reissner-Nordstrom spacetime, which has two horizons. The spectrum is
characterized by two distinct families of asymptotic resonances. We suggest and
demonstrate the according to Bohr's correspondence principle and in agreement
with the Bekenstein-Mukhanov quantization scheme, one of these resonances
corresponds to a fundamental change of Delta A=4hbar ln2 in the surface area of
the black-hole outer horizon. The second asymptotic resonance is associated
with a fundamental change of Delta Atot=4hbar ln3 in the total area of the
black hole (in the sum of the surface areas of the inner and outer horizons),
in accordance with a suggestion of Makela and Repo.


title: Infrared Gluon and Ghost Propagators

abstract:
  We derive the form of the infrared gluon propagator by proving a mapping in
the infrared of the quantum Yang-Mills and $\lambda\phi^4$ theories. The
equivalence is complete at a classical level. But while at a quantum level, the
correspondence is spoiled by quantum fluctuations in the ultraviolet limit, we
prove that it holds in the infrared where the coupling constant happens to be
very large. The infrared propagator is then obtained from the quantum field
theory of the scalar field producing a full spectrum. The results are in fully
agreement with recent lattice computations. We get a finite propagator at zero
momentum, the ghost propagator going to infinity as $1/p^{2+2\kappa}$ with
$\kappa=0$.

categories: hep-th hep-lat hep-ph math-ph math.AP math.MP


title: Self-regulated gravitational accretion in protostellar discs

abstract:
  We present a numerical model for the evolution of a protostellar disc that
has formed self-consistently from the collapse of a molecular cloud core. The
global evolution of the disc is followed for several million years after its
formation. The capture of a wide range of spatial and temporal scales is made
possible by use of the thin-disc approximation. We focus on the role of
gravitational torques in transporting mass inward and angular momentum outward
during different evolutionary phases of a protostellar disc with disc-to-star
mass ratio of order 0.1. In the early phase, when the infall of matter from the
surrounding envelope is substantial, mass is transported inward by the
gravitational torques from spiral arms that are a manifestation of the
envelope-induced gravitational instability in the disc. In the late phase, when
the gas reservoir of the envelope is depleted, the distinct spiral structure is
replaced by ongoing irregular nonaxisymmetric density perturbations. The
amplitude of these density perturbations decreases with time, though this
process is moderated by swing amplification aided by the existence of the
disc's sharp outer edge. Our global modelling of the protostellar disc reveals
that there is typically a residual nonzero gravitational torque from these
density perturbations, i.e. their effects do not exactly cancel out in each
region. In particular, the net gravitational torque in the inner disc tends to
be negative during first several million years of the evolution, while the
outer disc has a net positive gravitational torque. Our global model of a
self-consistently formed disc shows that it is also self-regulated in the late
phase, so that it is near the Toomre stability limit, with a near-uniform
Toomre parameter Q\approx 1.5-2.0. (Abstract abridged).


title: Lemaitre-Tolman-Bondi model and accelerating expansion

abstract:
  I discuss the spherically symmetric but inhomogeneous Lemaitre-Tolman- Bondi
(LTB) metric, which provides an exact toy model for an inhomogeneous universe.
Since we observe light rays from the past light cone, not the expansion of the
universe, spatial variation in matter density and Hubble rate can have the same
effect on redshift as acceleration in a perfectly homogeneous universe. As a
consequence, a simple spatial variation in the Hubble rate can account for the
distant supernova data in a dust universe without any dark energy. I also
review various attempts towards a semirealistic description of the universe
based on the LTB model.


title: D-Branes in Topological String Theory

abstract:
  This thesis is concerned with D-branes in topological string theory, focusing
on the description of B-type D-branes in topological Landau-Ginzburg models.
Such D-branes are characterized by matrix factorizations of the Landau-Ginzburg
superpotential. After reviewing some aspects of topological string theory we
give a detailed discussion of matrix factorizations. We discuss methods to
calculate the effective superpotential in minimal models, putting emphasis on
an algorithm to calculate the effective superpotential via deformations of
matrix factorizations. We furthermore perform a non-trivial check of
homological mirror symmetry for the torus.


title:
EROs found behind lensing clusters: II.Empirical properties,
  classification, and SED modelling based on multi-wavelength observations

abstract:
  We study the properties and nature of extremely red galaxies (ERO, R-K>5.6)
found behind two lensing clusters and compare them with other known galaxy
populations. New HST/ACS observations, Spitzer IRAC and MIPS, and Chandra/ACIS
observations of the two lensing clusters Abell 1835 and AC114 contemplate our
earlier optical and near-IR observations and have been used to study extremely
red objects (EROs) in these deep fields. We have found 6 and 9 EROs in Abell
1835 and AC114. Several (7) of these objects are undetected up to the I and/or
z band, and are hence ``optical'' drop-out sources. The photometric redshifts
of most of our sources (80%) are z~0.7-1.5. According to simple colour-colour
diagrams the majority of our objects would be classified as hosting old stellar
populations. However, there are clear signs of dusty starbursts for several
among them. These objects correspond to the most extreme ones in R-K colour. We
estimate a surface density of (0.97+-0.31) arcmin-2 for EROs with (R-K>5.6) at
K<20.5. Among our 15 EROs 6 (40 %) also classify as distant red galaxies
(DRGs). 11 of 13 EROs with available IRAC photometry also fulfil the selection
criteria for IRAC selected EROs (IEROs) of Yan et al. (2004). SED modelling
shows that ~ 36 % of the IEROs in our sample are luminous or ultra-luminous
infrared galaxies ((U)LIRG). Some very red DRGs are found to be very dusty
starbursts, even (U)LIRGs, as also supported by their mid-IR photometry. No
indication for AGNs is found, although faint activity cannot be excluded for
all objects. From mid-IR and X-ray data 5 objects are clearly classified as
starbursts. The derived properties are quite similar to those of DRGs and
IEROs, except for 5 extreme objects in terms of colours, for which a very high
extinction (Av>3) is found.


title:
Perturbational approach to the quantum capacity of additive Gaussian
  quantum channel

abstract:
  For a quantum channel with additive Gaussian quantum noise, at the large
input energy side, we prove that the one shot capacity is achieved by the
thermal noise state for all Gaussian state inputs, it is also true for
non-Gaussian input in the sense of first order perturbation. For a general case
of $n$ copies input, we show that up to first order perturbation, any
non-Gaussian perturbation to the product thermal state input has a less quantum
information transmission rate when the input energy tend to infinitive.


title:
Cherenkov Telescope Array: The next-generation ground-based gamma-ray
  observatory

abstract:
  High energy gamma-ray astronomy is a newly emerging and very successful
branch of astronomy and astrophysics. Exciting results have been obtained by
the current generation Cherenkov telescope systems such as H.E.S.S., MAGIC,
VERITAS and CANGAROO. The H.E.S.S. survey of the galactic plane has revealed a
large number of sources and addresses issues such as the question about the
origin of cosmic rays. The detection of very high energy emission from
extragalactic sources at large distances has provided insights in the star
formation during the history of the universe and in the understanding of active
galactic nuclei. The development of the very large Cherenkov telescope array
system (CTA) with a sensitivity about an order of magnitude better than current
instruments and significantly improved sensitivity is under intense discussion.
This observatory will reveal an order of magnitude more sources and due to its
higher sensitivity and angular resolution it will be able to detect new classes
of objects and phenomena that have not been visible until now. A combination of
different telescope types will provide the sensitivity needed in different
energy ranges.


title:
Spiral growth, two-dimensional nucleation, and the Ehrlich-Schwoebel
  effect

abstract:
  Frank's prediction of the spiral growth mode in 1949 defined a pivotal moment
in the history of crystal growth. In recent decades the topic has received less
attention, and instead we have seen a resurrection of two-dimensional
nucleation theory in the context of growth experiments on defect-free
homoepitaxial thin films. In particular, the key role of interlayer transport
controlled by step edge barriers of the Ehrlich-Schwoebel type in shaping the
morphology of multilayer films has been increasingly recognized. After a brief
review of the classical theory, this paper reports on a recent study of spiral
growth in the presence of step edge barriers. Our key observation is that step
edge barriers lead to unconventionally shaped spiral hillocks that display the
same characteristic ever-steepening height profiles as wedding cakes formed
during growth by two-dimensional nucleation. This prediction was verified
experimentally by inducing screw dislocations through ion bombardment of the
Pt(111) surface, thus creating a homoepitaxial growth system on which spiral
hillocks and wedding cakes coexist.


title:
Uniform limit laws of the logarithm for nonparametric estimators of the
  regression function in presence of censored data

abstract:
  In this paper, we establish uniform-in-bandwidth limit laws of the logarithm
for nonparametric Inverse Probability of Censoring Weighted (I.P.C.W.)
estimators of the multivariate regression function under random censorship. A
similar result is deduced for estimators of the conditional distribution
function. The uniform-in-bandwidth consistency for estimators of the
conditional density and the conditional hazard rate functions are also derived
from our main result. Moreover, the logarithm laws we establish are shown to
yield almost sure simultaneous asymptotic confidence bands for the functions we
consider. Examples of confidence bands obtained from simulated data are
displayed.


title: The perturbative Regge-calculus regime of Loop Quantum Gravity

abstract:
  The relation between Loop Quantum Gravity and Regge calculus has been pointed
out many times in the literature. In particular the large spin asymptotics of
the Barrett-Crane vertex amplitude is known to be related to the Regge action.
In this paper we study a semiclassical regime of Loop Quantum Gravity and show
that it admits an effective description in terms of perturbative
area-Regge-calculus. The regime of interest is identified by a class of states
given by superpositions of four-valent spin networks, peaked on large spins.
  As a probe of the dynamics in this regime, we compute explicitly two- and
three-area correlation functions at the vertex amplitude level. We find that
they match with the ones computed perturbatively in area-Regge-calculus with a
single 4-simplex, once a specific perturbative action and measure have been
chosen in the Regge-calculus path integral. Correlations of other geometric
operators and the existence of this regime for other models for the dynamics
are briefly discussed.


title: Recent progress of GaAsP HPD development for the MAGIC telescope project

abstract:
  Today the Hybrid Photon Detector (HPD) is one of the few low light level
(LLL) sensors that can provide an excellent single and multiple photoelectron
(ph.e.) amplitude resolution. The recently developed HPDs for the MAGIC
telescope project with a GaAsP photocathode, namely the R9792U-40, provide a
peak quantum efficiency (QE) of more than 50% and a pulse width of ~2 nsec. In
addition, the afterpulsing rate of these tubes is very low compared to that of
conventional photomultiplier tubes (PMTs), i.e. the value is ~300 times lower.
Photocathode aging measurements showed life time of more than 10 years under
standard operating conditions of the Cherenkov Telescopes. Here we want to
report on the recent progress with the above mentioned HPDs.


title: Correlated flares in models of a magnetized "canopy"

abstract:
  A model of the Lu-Hamilton kind is applied to the study of critical behavior
of the magnetized solar atmosphere. The main novelty is that its driving is
done via sources undergoing a diffusion. This mimics the effect of a virtual
turbulent substrate forcing the system. The system exhibits power-law
statistics not only in the size of the flares, but also in the distribution of
the waiting times.


title:
Spin polarization in biased Rashba-Dresselhaus two-dimensional electron
  systems

abstract:
  Based on spin-charge coupled drift-diffusion equations, which are derived
from kinetic equations for the spin-density matrix in a rigorous manner, the
electric-field-induced nonequilibrium spin polarization is treated for a
two-dimensional electron gas with both Rashba and Dresselhaus spin-orbit
coupling. Most emphasis is put on the consideration of the field-mediated spin
dynamics for a model with equal Rashba and Dresselhaus coupling constants, in
which the spin relaxation is strongly suppressed. Weakly damped
electric-field-induced spin excitations are identified, which remind of
space-charge waves in crystals.


title:
Sur une g\'en\'eralisation de la notion de syst\`eme dynamique de rang
  un d\'efinie par une propri\'et\'e de pistage (On a weak version of the rank
  one property defined by shadowing)

abstract:
  We investigate a shadowing property which appears naturally in the study of
piecewise monotonic maps of the interval. It turns out to be a weak form of the
rank one property, a well-known notion in abstract ergodic theory. We show that
this new property is implied by finite or even local rank, but that it is
logically independent of loose Bernoulliness. We give (counter)examples,
including L.B. systems with arbitrarily high-order polynomial complexity. The
shadowing property defines a small subset of all zero-entropy systems, in the
sense that it defines a closed set with empty interior with respect to the
$\db$-metric, induced by the Hamming distance. We also make some remarks on the
link between the shadowed system and the sequence assumed by the shadowing
property.


title:
Vanishing Viscosity Limits and Boundary Layers for Circularly Symmetric
  2D Flows

abstract:
  We continue the work of Lopes Filho, Mazzucato and Nussenzveig Lopes [LMN],
on the vanishing viscosity limit of circularly symmetric viscous flow in a disk
with rotating boundary, shown there to converge to the inviscid limit in
$L^2$-norm as long as the prescribed angular velocity $\alpha(t)$ of the
boundary has bounded total variation. Here we establish convergence in stronger
$L^2$ and $L^p$-Sobolev spaces, allow for more singular angular velocities
$\alpha$, and address the issue of analyzing the behavior of the boundary
layer. This includes an analysis of concentration of vorticity in the vanishing
viscosity limit. We also consider such flows on an annulus, whose two boundary
components rotate independently.
  [LMN] Lopes Filho, M. C., Mazzucato, A. L. and Nussenzveig Lopes, H. J.,
Vanishing viscosity limit for incompressible flow inside a rotating circle,
preprint 2006.


title: Global rigidity in CR geometry: the Schoen-Webster theorem

abstract:
  Schoen-Webster theorem asserts a pseudoconvex CR manifold whose automorphism
group acts non properly is either the standard sphere or the Heisenberg space.
The purpose of this paper is to survey successive works around this result and
then provide a short geometric proof in the compact case.


title: Possible nature of $Z^+(4430)$

abstract:
  We discuss exotic states X(3872) and $Z^+(4430)$, observed recently in
experiment Belle. The QCD-string based explanation is suggested.