title:
Universal Doublet-Singlet Higgs Couplings and phenomenology at the CERN
  Large Hadron Collider

abstract:
  We consider a minimal extension of the standard model where a real, gauge
singlet scalar field is added to the standard spectrum. Introducing the Ansatz
of universality of scalar couplings, we are led to a scenario which has a set
of very distinctive and testable predictions: (i) the mixing between the
standard model Higgs and the new state is near maximal, (ii) the ratio of the
two Higgs mass eigenstates is fixed ($\sim \sqrt{3}$), (iii) the decay modes of
each of the two eigenstates are standard model like. We also study how
electroweak precision tests constrain this scenario. We predict the lighter
Higgs to lie in the range of 114 and 145 GeV, and hence the heavier one between
198 and 250 GeV. The predictions of the model can be tested at the upcoming
LHC.


title:
Experimental simulation of fractional statistics of abelian anyons in
  the Kitaev lattice-spin model

abstract:
  In two-dimensions, the laws of physics even permit the existence of anyons
which exhibit fractional statistics ranging continuously from bosonic to
fermionic behaviour. They have been responsible for the fractional quantum Hall
effect and proposed as candidates for naturally fault-tolerant quantum
computation. Despite these remarkable properties, the fractional statistics of
anyons has never been observed in nature directly. Here we report the
demonstration of fractional statistics of anyons by simulation of the first
Kitaev lattice-spin model on a nuclear magnetic resonance system. We encode
four-body interactions of the lattice-spin model into two-body interactions of
an Ising spin chain in molecules. It can thus efficiently prepare and operate
the ground state and excitations of the model Hamiltonian. This quantum system
with convenience of manipulation and detection of abelian anyons reveals
anyonic statistical properties distinctly. Our experiment with interacted
Hamiltonian could also prove useful in the long run to the control and
application of anyons.


title: Q-systems as cluster algebras

abstract:
  Q-systems first appeared in the analysis of the Bethe equations for the
XXX-model and generalized Heisenberg spin chains. Such systems are known to
exist for any simple Lie algebra and many other Kac-Moody algebras. We
formulate the Q-system associated with any simple, simply-laced Lie algebras g
in the language of cluster algebras, and discuss the relation of the
polynomiality property of the solutions of the $Q$-system in the initial
variables, which follows from the representation-theoretical interpretation, to
the Laurent phenomenon in cluster algebras.


title: The uniform primality conjecture for elliptic curves

abstract:
  An elliptic divisibility sequence, generated by a point in the image of a
rational isogeny, is shown to possess a uniformly bounded number of prime
terms. This result applies over the rational numbers, assuming Lang's
conjecture, and over the rational function field, unconditionally. In the
latter case, a uniform bound is obtained on the index of a prime term.
Sharpened versions of these techniques are shown to lead to explicit results
where all the irreducible terms can be computed.


title: Parametric Resonance and Cosmological Gravitational Waves

abstract:
  We investigate the production of gravitational waves due to quantum
fluctuations of the vacuum during the transition from the inflationary to the
radiation-dominated eras of the universe, assuming this transition to be
dominated by the phenomenon of parametric resonance. The energy spectrum of the
gravitational waves is calculated using the method of continuous Bogoliubov
coefficients, which avoids the problem of overproduction of gravitons at large
frequencies. We found, on the sole basis of the mechanism of quantum
fluctuations, that the resonance field leaves no explicit and distinctive
imprint on the gravitational-wave energy spectrum, apart an overall upward or
downward translation. Therefore, the main features in the spectrum are due to
the inflaton field, which leaves a characteristic imprint at frequencies of the
order of MHz/GHz.


title: Mass modelling of Abell 2634: avoiding the interloper bias

abstract:
  Using an example of the Abell 2634 galaxy cluster we discuss the effect of
contamination of kinematic data by interlopers and its impact on mass
modelling. The cluster data reveal rich substructure along the line of sight.
We demonstrate that it is necessary to apply a few independent methods of
interloper removal in order to obtain a reliable sample of cluster members. We
present results of three such methods which are commonly used in the literature
and have been recently extensively tested on simulated data. Only two of them
lead to consistent and reliable samples of cluster galaxies. For both of them
we provide parameters of the best-fitting NFW density profile by fitting an
isotropic solution of the Jeans equation to the velocity dispersion profiles.


title:
Square root voting in the Council of the European Union: Rounding
  effects and the Jagiellonian Compromise

abstract:
  In recent years, enlargement of the European Union has brought with it
renewed discussion of voting arrangements in the Council of the EU. During
these negotiations, the Polish government proposed a voting scheme that gives
each country a voting weight proportional to the square root of its population,
and sets a quota according to an optimality condition ("Jagiellonian
Compromise"). In this paper, the optimal quota is found exactly for the current
population data from the 27 EU member states, and it is found that rounding of
the voting weights can be used to improve the voting scheme.


title:
Two-nucleon problem in semi-relativistic baryon chiral perturbation
  theory

abstract:
  We consider a symmetry-preserving approach to the nucleon-nucleon scattering
problem in the framework of the higher-derivative formulation of baryon chiral
perturbation theory. Within this framework the leading-order amplitude is
calculated by solving renormalizable equations and corrections are taken into
account perturbatively.


title: The shear-induced alpha-effect and long-term variations in solar dynamo

abstract:
  The consequences of the shear-induced alpha effect to the long-term
modulation of magnetic activity are examined with the help of the axisymmetric
numerical dynamo model that includes the self-consistent description of the
angular momentum balance, heat transport and magnetic field generation in the
spherical shell. We find that the shear contributions to alpha effect can
complicate the long-term behaviour of the large-scale magnetic activity and
differential rotation in nonlinear dynamo. Additionally we consider the impact
secular magnetic activity variations to the secular modulations of the solar
luminosity and radius.


title: Curvature of the phase transition line in the mu-T plane

abstract:
  We determined the curvature of the phase transition line in the mu-T plane
using a Taylor expansion in mu. The Polyakov loop and the strange quark number
susceptibility were measured to locate the pseudocritical line. The analysis
was carried out on Nt=4,6,8,10 lattices generated with a Symanzik improved
gauge and stout-link improved (2+1) flavour staggered fermion action using
physical quark masses.


title: Perturbations and Stability of Higher-Dimensional Black Holes

abstract:
  In this lecture, I explain the gauge-invariant formulation for perturbations
of background spacetimes with untwisted homologous Einstein fibres, which
include lots of practically important spacetimes such as static black holes,
static black branes and rotating black holes in various dimensions. As
applications, we discuss the stability of static black holes in higher
dimensions and flat black branes.


title: On Bargmann Representations of Wigner Function

abstract:
  By using the localized character of canonical coherent states, we give a
straightforward derivation of the Bargmann integral representation of Wigner
function (W). A non-integral representation is presented in terms of a
quadratic form V*FV, where F is a self-adjoint matrix whose entries are
tabulated functions and V is a vector depending in a simple recursive way on
the derivatives of the Bargmann function. Such a representation may be of use
in numerical computations. We discuss a relation involving the geometry of
Wigner function and the spacial uncertainty of the coherent state basis we use
to represent it.


title: Symmetry, shape, and order

abstract:
  Packing problems have been of great interest in many diverse contexts for
many centuries. The optimal packing of identical objects has been often invoked
to understand the nature of low temperature phases of matter. In celebrated
work, Kepler conjectured that the densest packing of spheres is realized by
stacking variants of the face-centered cubic lattice and has a packing fraction
of $\pi/(3\sqrt{2}) \sim 0.7405$. Much more recently, an unusually high density
packing of approximately 0.770732 was achieved for congruent ellipsoids. Such
studies are relevant for understanding the structure of crystals, glasses, the
storage and jamming of granular materials, ceramics, and the assembly of viral
capsid structures. Here we carry out analytical studies of the stacking of
close-packed planar layers of systems made up of truncated cones possessing
uniaxial symmetry. We present examples of high density packing whose order is
characterized by a {\em broken symmetry} arising from the shape of the
constituent objects. We find a biaxial arrangement of solid cones with a
packing fraction of $\pi/4$. For truncated cones, there are two distinct
regimes, characterized by different packing arrangements, depending on the
ratio $c$ of the base radii of the truncated cones with a transition at
$c^*=\sqrt{2}-1$.


title:
A class of exactly solvable Schroedinger equation with moving boundary
  conditions

abstract:
  Using first and second order supersymmetry formalism we obtain a class of
exactly solvable potentials subject to moving boundary conditions.


title:
Gauge-invariant truncation scheme for the Schwinger-Dyson equations of
  QCD

abstract:
  We present a new truncation scheme for the Schwinger-Dyson equations of QCD
that respects gauge invariance at any level of the dressed loop expansion. When
applied to the gluon self-energy, it allows for its non-perturbative treatment
without compromising the transversality of the solution, even when entire sets
of diagrams (most notably the ghost loops) are omitted, or treated
perturbatively.


title: The Banff Challenge: Statistical Detection of a Noisy Signal

abstract:
  Particle physics experiments such as those run in the Large Hadron Collider
result in huge quantities of data, which are boiled down to a few numbers from
which it is hoped that a signal will be detected. We discuss a simple
probability model for this and derive frequentist and noninformative Bayesian
procedures for inference about the signal. Both are highly accurate in
realistic cases, with the frequentist procedure having the edge for interval
estimation, and the Bayesian procedure yielding slightly better point
estimates. We also argue that the significance, or $p$-value, function based on
the modified likelihood root provides a comprehensive presentation of the
information in the data and should be used for inference.


title: sp(4,R)-systematics of atomic nuclei. F-multiplets and nuclear structure

abstract:
  A systematics of the atomic nuclei in the frame of the nucleon number $A = Z
+ N$ and the proton-neutron difference $F = Z - N$ is considered. The
classification scheme is provided by means of the non-compact algebra
$sp(4,R)$. In this scheme the nuclei are ordered into isobaric multiplets, for
which $A={fix}$, as well as in F-multiplets, for which $F={fix}$. The
dependence of the mass excess $\Delta$, the first exited states $E_{2^+}$ and
the ratio $R_2=E_{4^+}/E_{2^+}$ on the nucleon number $A$ is empirically
investigated within the $F$-multiplets. Appropriate filters are used to study
the properties of the mass excess. Many structural effects are observed. The
mirror symmetry is clearly indicated for the energy levels of the nuclei with
the same value of $A$ and opposite $F$-values.


title: Nucleon spin structure and QCD spin physics

abstract:
  Our knowledge of the nucleon spin structure has greatly improved over the
last twenty years or so, but still many fundamental questions remain unsolved.
I will try to review some of the puzzling aspects of the structure of the
nucleon spin, in particular, what is known, what remains to be discovered and
the prospects for the near future. I will also focus on some current activities
in QCD spin physics.


title:
Testbed for Wireless Vehicle Communication: a Simulation Approach based
  on Three-Phase Traffic Theory

abstract:
  A testbed for wireless vehicle communication based on a microscopic model in
the framework of three-phase traffic theory is presented. In this testbed,
vehicle motion in traffic flow and analyses of a vehicle communication channel
access based on IEEE 802.11e mechanisms, radio propagation modeling, message
reception characteristics as well as all other effects associated with ad-hoc
networks are integrated into a three-phase traffic flow model. Based on
simulations of this testbed, some statistical features of ad-hoc vehicle
networks as well as the effect of C2C communication on increase in the
efficiency and safety of traffic are studied.


title:
Chaos Synchronization with Dynamic Filters: Two Way is Better Than One
  Way

abstract:
  Two chaotic systems which interact by mutually exchanging a signal built from
their delayed internal variables, can synchronize. A third unit may be able to
record and to manipulate the exchanged signal. Can the third unit synchronize
to the common chaotic trajectory, as well? If all parameters of the system are
public, a proof is given that the recording system can synchronize as well.
However, if the two interacting systems use private commutative filters to
generate the exchanged signal, a driven system cannot synchronize. It is shown
that with dynamic private filters the chaotic trajectory even cannot be
calculated. Hence two way (interaction) is more than one way (drive). The
implication of this general result to secret communication with chaos
synchronization is discussed.


title:
Direct resolution of unoccupied states in solids via two photon
  photoemission

abstract:
  Non-linear effects in photoemission are shown to open a new access to the
band structure of unoccupied states in solids, totally different from hitherto
used photoemission spectroscopy. Despite its second-order nature, strong
resonant transitions occur, obeying exact selection rules of energy, crystal
symmetry, and momentum. Ab-initio calculations are used to demonstrate that
such structures are present in low-energy laser spectroscopy experimental
measurements on Si previously published. Similar resonances are expected in
ultraviolet angle-resolved photoemission spectra, as shown in a model
calculation on Al.


title: Supergravitons from one loop perturbative N=4 SYM

abstract:
  We determine the partition function of 1/16 BPS operators in N=4 SYM at weak
coupling at the one-loop level in the planar limit. This partition function is
significantly different from the one computed at zero coupling. We find that it
coincides precisely with the partition function of a gas of 1/16 BPS
`supergravitons' in AdS_5xS^5.


title:
A2163: Merger events in the hottest Abell galaxy cluster I. Dynamical
  analysis from optical data

abstract:
  We present a detailed optical analysis of the galaxy cluster A2163 based on
new multicolor wide field imaging and medium-to-high resolution (R~2000)
spectroscopy. While X-ray observations have revealed that merging processes are
present in this cluster, the merging scenario is complex and not well-defined.
We undertook a complementary optical analysis, aiming to understand the
dynamics of the system, to add constraints to the merging scenario and to test
its effect on the properties of galaxies. We provide a spectroscopic catalog of
512 new objects, where 361 galaxies are identified as cluster members. We
derived estimates of the mean redshift and velocity dispersion: z= 0.2005 +/-
0.0003 and 1434 +/- 60 km/s, and performed a detailed dynamical analysis of
unprecedented accuracy. We detected multiple evidences of merging events: i)
strong subclustering in the galaxy density distribution, showing a main central
component A2163-A, a northern one A2163-B, visible both in optical and in
X-ray, and other substructures detected in optical, ii) bimodality in the
density distribution for A2163-A, strong segregation between gaz and galaxies,
and between galaxies of different luminosities, iii) low-density structures
oriented along specific axes: mainly the EW direction, and the NS one,
embedding the main substructures, iv) bimodality in the velocity distribution
and a velocity gradient (~1250 km/s) along the NE/SW axis of the cluster. A2163
is exceptionally massive, with Mvir = 3.8 +/- 0.4 10**15 Msol/h70. Our analysis
supports a scenario in which A2163-A has undergone a recent (t ~ 0.5 Gyr)
merger along a a NE/SW (or E--W) axis, and A2163-B is connected to the main
complex, probably infalling on A2163-A. (abridged)


title: Community Structure in Graphs

abstract:
  Graph vertices are often organized into groups that seem to live fairly
independently of the rest of the graph, with which they share but a few edges,
whereas the relationships between group members are stronger, as shown by the
large number of mutual connections. Such groups of vertices, or communities,
can be considered as independent compartments of a graph. Detecting communities
is of great importance in sociology, biology and computer science, disciplines
where systems are often represented as graphs. The task is very hard, though,
both conceptually, due to the ambiguity in the definition of community and in
the discrimination of different partitions and practically, because algorithms
must find ``good'' partitions among an exponentially large number of them.
Other complications are represented by the possible occurrence of hierarchies,
i.e. communities which are nested inside larger communities, and by the
existence of overlaps between communities, due to the presence of nodes
belonging to more groups. All these aspects are dealt with in some detail and
many methods are described, from traditional approaches used in computer
science and sociology to recent techniques developed mostly within statistical
physics.


title: Coset Space Dimensional Reduction of Einstein--Yang--Mills theory

abstract:
  In the present contribution we extend our previous work by considering the
coset space dimensional reduction of higher-dimensional Einstein--Yang--Mills
theories including scalar fluctuations as well as Kaluza--Klein excitations of
the compactification metric and we describe the gravity-modified rules for the
reduction of non-abelian gauge theories.


title:
A hybrid method for determining particle masses at the Large Hadron
  Collider with fully identified cascade decays

abstract:
  A new technique for improving the precision of measurements of SUSY particle
masses at the LHC is introduced. The technique involves kinematic fitting of
events with two fully identified decay chains. We incorporate both event ETmiss
constraints and independent constraints provided by kinematic end-points in
experiment invariant mass distributions of SUSY decay products. Incorporation
of the event specific information maximises the information used in the fit and
is shown to reduce the mass measurement uncertainites by ~30% compared to
conventional fitting of experiment end-point constraints for the SPS1a
benchmark model.


title: Horizons and Tunneling in the Euclidean False Vacuum

abstract:
  In the thin-wall approximation, the decay of a gravitating false vacuum to a
lower-energy state is affected by the cosmological horizon structure in both
spaces. The nucleation radius of a bubble of true vacuum depends on the surface
tension of its boundary and equals the false vacuum cosmological horizon at a
critical tension. We argue that there is no tunneling instanton solution beyond
the critical tension and argue that there is therefore a bound on allowed
membrane tension in theories which rely on semiclassical tunneling to relax the
cosmological constant.


title: X-ray source populations in the Magellanic Clouds

abstract:
  Early X-ray surveys of the Magellanic Clouds (MCs) were performed with the
imaging instruments of the Einstein, ASCA and ROSAT satellites revealing
discrete X-ray sources and large-scale diffuse emission. Large samples of
supernova remnants, high and low mass X-ray binaries and super-soft X-ray
sources could be studied in detail. Today, the major X-ray observatories
XMM-Newton and Chandra with their advanced angular and spectral resolution and
extended energy coverage are ideally suited for detailed population studies of
the X-ray sources in these galaxies and to draw conclusions on our own Galaxy.
We summarize our knowledge about the X-ray source populations in the MCs from
past missions and present first results from systematic studies of the Small
Magellanic Cloud (SMC) using the growing number of archival XMM-Newton
observations.


title: On effaceability of certain $\delta$-functors

abstract:
  We prove a conjecture of the first author for $GL_2(F)$, where $F$ is a
finite extension of $Q_p$.


title: Spin tunneling in junctions with disordered ferromagnets

abstract:
  We provide compelling evidence to establish that, contrary to one's
elementary guess, the tunneling spin polarization (TSP) of amorphous CoFeB is
larger than that of highly textured fcc CoFeB. First principles atomic and
electronic structure calculations reveal striking agreement between the
measured TSP and the predicted s-electron spin polarization. Given the
disordered structure of the ternary alloy, not only do these results strongly
endorse our communal understanding of tunneling through AlOx, but they also
portray the key concepts that demand primary consideration in such complex
systems.


title:
Study Of The Fundamental Physical Principles in Atmospheric Modeling
  Based On Identification Of Atmosphere - Climate Control Factors: Bromine
  Explosion At The Polar Arctic Sunrise

abstract:
  We attempt is to provide accumulated evidence and qualitative understanding
of the associated atmospheric phenomena of the Arctic bromine explosion and
their role in the functioning of the biotic Earth. We rationalize the empirical
expression of the bromine influx into atmospheric boundary layer and calculate
total amounts of the tropospheric BrO and Bry of the Arctic origin. Based on
the quantities and partitioning of the reactive bromine species, we estimate
the biogeochemical parametric constraint on the surface ozone field of the
springtime NH. The constraint expresses strong relationship between
atmosphere-climate control factors of the Earth's life and of external energy
source. Physical atmosphere can be seen as a complex network of maximum
complexity. Henceforth, we analyze the network context of the Arctic bromine
pollution. We suggest that demonstrated attitudinal approach to the distributed
surface flux would be successfully used in the innovative atmospheric modeling.
The analysis is illustrated by GEM model results which stay in a good agreement
with the observational data and support the original idea of the global NH
effect of bromine chemistry.


title:
SDSSJ124155.33+114003.7 -- a Missing Link Between Compact Elliptical and
  Ultracompact Dwarf Galaxies

abstract:
  We report the discovery of a compact object (R_e = 32 pc, M_B = -12.34 mag)
at a projected distance of 9 kpc from Messier 59, a giant elliptical in the
Virgo cluster. Using HST imaging and SDSS spectroscopy, both available in the
Virtual Observatory, we find that this object has a blue core containing
one-quarter of the light, and a redder n=1 Sersic envelope, as well as
luminosity-weighted age of 9.3 +/- 1.4 Gyr, a metallicity of -0.03 +/- 0.04 dex
and a velocity dispersion of 48 +/- 5 km/s. While ultra-compact dwarfs (UCDs)
in the face-on view of the Fundamental Plane are found to form a sequence
connecting the highest-luminosity globular clusters with the lowest-luminosity
dwarf ellipticals, the compact object near M59 lies in between this UCD
sequence and the positions of compact ellipticals. Its stellar age,
metallicity, and effective surface brightness are similar to low-luminosity
ellipticals and lenticulars, suggesting that SDSSJ124155.33+114003.7 is a
result of the tidal stripping of such an object.


title:
Lorentz covariant statistical mechanics and thermodynamics of the
  relativistic ideal gas and preferred frame

abstract:
  The Lorentz covariant classical and quantum statistical mechanics and
thermodynamics of an ideal relativistic gas of bradyons (particles slower than
light), luxons (particles moving with the speed of light) and tachyons
(hypothetical particles faster than light) is discussed. The Lorentz covariant
formulation is based on the preferred frame approach which among others enables
consistent, free of paradoxes description of tachyons. The thermodynamic
functions within the covariant approach are obtained both in classical and
quantum case.


title:
Some unbounded functions of intermittent maps for which the central
  limit theorem holds

abstract:
  We compute some dependence coefficients for the stationary Markov chain whose
transition kernel is the Perron-Frobenius operator of an expanding map $T$ of
$[0, 1]$ with a neutral fixed point. We use these coefficients to prove a
central limit theorem for the partial sums of $f\circ T^i$, when $f$ belongs to
a large class of unbounded functions from $[0, 1]$ to ${\mathbb R}$. We also
prove other limit theorems and moment inequalities.


title:
Oxygen molecular plasma at ambient temperature and elevated or high
  pressure

abstract:
  Usually microscopic electrostatic field around ions is neglected when the
ionization energy is concerned. The ionization energy is considered to be equal
to that of a separate atom (molecule). Here the energy of the electrostatic
field around ions is taken into account. It is shown that the energy of this
field contributes to decrease in the effective ionization energy. The effective
ionization energy may turn to zero at some critical concentration of
delocalized electrons. This leads to a complete ionization of the atoms
(molecules). Concrete calculations were performed for oxygen molecular gas.


title: Relativistic ideal Fermi gas at zero temperature and preferred frame

abstract:
  We discuss the limit T->0 of the relativistic ideal Fermi gas of luxons
(particles moving with the speed of light) and tachyons (hypothetical particles
faster than light) based on observations of our recent paper: K. Kowalski, J.
Rembielinski and K.A. Smolinski, Phys. Rev. D, 76, 045018 (2007). For bradyons
this limit is in fact the nonrelativistic one and therefore it is not studied
herein.


title: Galaxy peculiar velocities and evolution-bias

abstract:
  Galaxy bias can be split into two components: a formation-bias based on the
locations of galaxy creation, and an evolution-bias that details their
subsequent evolution. In this letter we consider evolution-bias in the peaks
model. In this model, galaxy formation takes place at local maxima in the
density field, and we analyse the subsequent peculiar motion of these galaxies
in a linear model of structure formation. The peak restriction yields
differences in the velocity distribution and correlation between the galaxy and
the dark matter fields, which causes the evolution-bias component of the total
bias to evolve in a scale-dependent way. This mechanism naturally gives rise to
a change in shape between galaxy and matter correlation functions that depends
on the mean age of the galaxy population. This model predicts that older
galaxies would be more strongly biased on large scales compared to younger
galaxies. Our arguments are supported by a Monte-Carlo simulation of galaxy
pairs propagated using the Zel'dovich-approximation for describing linear
peculiar galaxy motion.


title:
Topological Order, Dimerization, and Spinon Deconfinement in Frustrated
  Spin Ladders

abstract:
  We consider topological order and dimer order in several frustrated spin
ladder models, which are related to higher dimensional models of current
interest; we also address the occurrence of fractionalized phases with
deconfined spinon excitations in these models. Combining results obtained with
both analytic and numerical methods, we discuss how the occurrence of dimerized
or fractionalized phases are dictated by the system's geometry.


title: Subdiffusive behavior generated by irrational rotations

abstract:
  The origin of deterministic diffusion is a matter of discussion. We study the
asymptotic distributions of the sums $y_n(x)=\sum_{k=0}^{n-1}\psi (x+k\alpha)$,
where $\psi$ is a periodic function of bounded variation and $\alpha$ an
irrational number. It is known that no diffusion process will be observed.
Nevertheless, we find a picewise constant function $\psi$ and an increasing
sequence of integer $(n_j)_j$ such that the limit distribution of the sequence
$(y_{n_j}/\sqrt j)_j$ is Gaussian (with stricly positive variance). If $\alpha$
is of constant type, we show that the sequence $(n_j)_j$ may be taken to grow
exponentially (this is close to optimal in some sense, and one has
$||y_{n_j}||_{\mathrm L^2}\sim \max_{0\le k\le n_j}||y_k||_{\mathrm L^2}$ as
$j\to\infty$). We give an heuristic link with the theory of expanding maps of
the interval.


title:
Longitudinal Ion Acceleration from High-Intensity Laser Interactions
  with Underdense Plasma

abstract:
  Longitudinal ion acceleration from high-intensity (I ~ 10^20 Wcm^-2) laser
interactions with helium gas jet targets (n_e ~ 0.04 n_c) have been observed.
The ion beam has a maximum energy for He^2+ of approximately 40 MeV and was
directional along the laser propagation path, with the highest energy ions
being collimated to a cone of less than 10 degrees. 2D particle-in-cell
simulations have been used to investigate the acceleration mechanism. The time
varying magnetic field associated with the fast electron current provides a
contribution to the accelerating electric field as well as providing a
collimating field for the ions. A strong correlation between the plasma density
and the ion acceleration was found. A short plasma scale-length at the vacuum
interface was observed to be beneficial for the maximum ion energies, but the
collimation appears to be improved with longer scale-lengths due to enhanced
magnetic fields in the ramp acceleration region.


title: Review of Top Quark Physics Results

abstract:
  As the heaviest known fundamental particle, the top quark has taken a central
role in the study of fundamental interactions. Production of top quarks in
pairs provides an important probe of strong interactions. The top quark mass is
a key fundamental parameter which places a valuable constraint on the Higgs
boson mass and electroweak symmetry breaking. Observations of the relative
rates and kinematics of top quark final states constrain potential new physics.
In many cases, the tests available with study of the top quark are both
critical and unique. Large increases in data samples from the Fermilab Tevatron
have been coupled with major improvements in experimental techniques to produce
many new precision measurements of the top quark. The first direct evidence for
electroweak production of top quarks has been obtained, with a resulting direct
determination of $V_{tb}$. Several of the properties of the top quark have been
measured. Progress has also been made in obtaining improved limits on potential
anomalous production and decay mechanisms. This review presents an overview of
recent theoretical and experimental developments in this field. We also provide
a brief discussion of the implications for further efforts.


title: MHD models and synthetic synchrotron maps for the jet of M87

abstract:
  We present a self-consistent MHD model for the jet of M87. The model consist
of two distinct zones: an inner relativistic outflow, which we identify with
the observed jet, and an outer cold disk-wind. While the former does not
self-collimate efficiently due to its high effective inertia, the latter
fulfills all the conditions for efficient collimation by the
magneto-centrifugal mechanism. Given the right balance between the effective
inertia of the inner flow and the collimation efficiency of the outer disk
wind, the relativistic flow is magnetically confined into a well collimated
beam for a wide range of parameters and matches the measurements of the opening
angle of M87 over several orders of magnitude in spatial extent.
  In the second part of this work, we present synthetic synchrotron emission
maps for our MHD models. In principle the two-zone model can reproduce the
morphological structure seen in radio observations, as central-peaked profiles
across the jet close the the source, limb-bright further down the jet, and a
bright knot close to the position of HST-1. However it is difficult to
reconcile all features into a single set of parameters.


title:
Temporal Coherence and Indistinguishability in Two-Photon Interference
  Effects

abstract:
  We show that temporal two-photon interference effects involving the signal
and idler photons created by parametric down-conversion can be fully
characterized in terms of the variations of two length parameters--called the
biphoton path-length difference and the biphoton path-asymmetry- length
difference--which we construct using the six different length parameters that a
general two-photon interference experiment involves. We perform an experiment
in which the effects of the variations of these two parameters can be
independently controlled and studied. In our experimental setup, which does not
involve mixing of signal and idler photons at a beam splitter, we further
report observations of Hong-Ou-Mandel- (HOM-)like effects both in coincidence
and in one-photon count rates. As an important consequence, we argue that the
HOM and the HOM-like effects are best described as observations of how
two-photon coherence changes as a function of the biphoton path-
asymmetry-length difference.


title: A Note on the Statistics of Hardcore Fermions

abstract:
  It is shown that the statistics of the hardcore fermions is A-superstatistics
of order one [see T.D.P. J. Math. Phys. 21, 1293 (1980)]. The Pauli principle
for these particles is formulated. The Hubbard operators, which constitute a
basis in the Lie superalgebra gl(1|n), are expressed via the creation and the
annihilation operators of the hardcore fermions.

categories: cond-mat.str-el hep-th math-ph math.MP quant-ph


title: Experiments with a Convex Polyhedral Analysis Tool for Logic Programs

abstract:
  Convex polyhedral abstractions of logic programs have been found very useful
in deriving numeric relationships between program arguments in order to prove
program properties and in other areas such as termination and complexity
analysis. We present a tool for constructing polyhedral analyses of
(constraint) logic programs. The aim of the tool is to make available, with a
convenient interface, state-of-the-art techniques for polyhedral analysis such
as delayed widening, narrowing, "widening up-to", and enhanced automatic
selection of widening points. The tool is accessible on the web, permits user
programs to be uploaded and analysed, and is integrated with related program
transformations such as size abstractions and query-answer transformation. We
then report some experiments using the tool, showing how it can be conveniently
used to analyse transition systems arising from models of embedded systems, and
an emulator for a PIC microcontroller which is used for example in wearable
computing systems. We discuss issues including scalability, tradeoffs of
precision and computation time, and other program transformations that can
enhance the results of analysis.


title:
Orthogonal Laurent polynomials on the unit circle and snake-shaped
  matrix factorizations

abstract:
  Let there be given a probability measure $\mu$ on the unit circle $\TT$ of
the complex plane and consider the inner product induced by $\mu$. In this
paper we consider the problem of orthogonalizing a sequence of monomials
$\{z^{r_k}\}_k$, for a certain order of the $r_k\in\mathbb{Z}$, by means of the
Gram-Schmidt orthogonalization process. This leads to a basis of orthonormal
Laurent polynomials $\{\psi_k\}_k$. We show that the matrix representation with
respect to the basis $\{\psi_k\}_k$ of the operator of multiplication by $z$ is
an infinite unitary or isometric matrix allowing a 'snake-shaped' matrix
factorization. Here the 'snake shape' of the factorization is to be understood
in terms of its graphical representation via sequences of little line segments,
following an earlier work of Delvaux and Van Barel. We show that the shape of
the snake is determined by the order in which the monomials $\{z^{r_k}\}_k$ are
orthogonalized, while the 'segments' of the snake are canonically determined in
terms of the Schur parameters for $\mu$. Isometric Hessenberg matrices and
unitary five-diagonal matrices (CMV matrices) follow as a special case of the
presented formalism.


title:
Turbulent dynamics of pipe flow captured in a reduced model: puff
  relaminarisation and localised `edge' states

abstract:
  Fully 3-dimensional computations of flow through a long pipe demand a huge
number of degrees of freedom, making it very expensive to explore parameter
space and difficult to isolate the structure of the underlying dynamics. We
therefore introduce a `2+epsilon' dimensional model of pipe flow which is a
minimal 3-dimensionalisation of the axisymmetric case: only sinusoidal
variation in azimuth plus azimuthal shifts are retained, yet the same dynamics
familiar from experiments are found. In particular the model retains the
subcritical dynamics of fully resolved pipe flow, capturing realistic localised
`puff'-like structures which can decay abruptly after long times, as well as
global `slug' turbulence. Relaminarisation statistics of puffs reproduce the
memoryless feature of pipe flow and indicate the existence of a Reynolds number
about which lifetimes diverge rapidly, provided that the pipe is sufficiently
long. Exponential divergence of the lifetime is prevalent in shorter periodic
domains. In a short pipe, exact travelling-wave solutions are found nearby to
flow trajectories on the boundary between laminar and turbulent flow. In a long
pipe, the attracting state on the laminar-turbulent boundary is a localised
structure which resembles a smoothened puff. This `edge' state remains
localised even for Reynolds numbers where the turbulent state is global.


title:
Effective generation of entangled states and realization of quantum gate
  operations in cavity QED

abstract: This paper has been withdrawn by the author due to some problems.


title: Bosons in one-dimensional incommensurate superlattices

abstract:
  We investigate numerically the zero-temperature physics of the
one-dimensional Bose-Hubbard model in an incommensurate cosine potential,
recently realized in experiments with cold bosons in optical superlattices L.
Fallani et al., Phys. Rev. Lett. 98, 130404, (2007)]. An incommensurate cosine
potential has intermediate properties between a truly periodic and a fully
random potential, displaying a characteristic length scale (the quasi-period)
which is shown to set a finite lower bound to the excitation energy of the
system at special incommensurate fillings. This leads to the emergence of
gapped incommensurate band-insulator (IBI) phases along with gapless Bose-glass
(BG) phases for strong quasi-periodic potential, both for hardcore and softcore
bosons. Enriching the spatial features of the potential by the addition of a
second incommensurate component appears to remove the IBI regions, stabilizing
a continuous BG phase over an extended parameter range. Moreover we discuss the
validity of the local-density approximation in presence of a parabolic trap,
clarifying the notion of a local BG phase in a trapped system; we investigate
the behavior of first- and second-order coherence upon increasing the strength
of the quasi-periodic potential; and we discuss the ab-initio derivation of the
Bose-Hubbard Hamiltonian with quasi-periodic potential starting from the
microscopic Hamiltonian of bosons in an incommensurate superlattice.


title: Free pluriharmonic majorants and noncommutative interpolation

abstract:
  In this paper, we initiate the study of sub-pluriharmonic curves in
Cuntz-Toeplitz algebras and free pluriharmonic majorants on noncommutative
balls. We are lead to a characterization of the noncommutative Hardy space
$H^2_{\bf ball}$ in terms of free pluriharmonic majorants, and to a Schur type
description of the unit ball of $H^2_{\bf ball}$. These results are used to
solve a multivariable commutant lifting problem and provide a description of
all solutions.


title: A Generalized Scaling Function for AdS/CFT

abstract:
  We study a refined large spin limit for twist operators in the sl(2) sector
of AdS/CFT. We derive a novel non-perturbative equation for the generalized
two-parameter scaling function associated to this limit, and analyze it at weak
coupling. It is expected to smoothly interpolate between weakly coupled gauge
theory and string theory at strong coupling.


title: Anomalous gamma gamma interaction

abstract:
  Data from LEP2 on hadron production in gamma gamma interactions at high pT
exceed the predictions of QCD by about an order of magnitude. The amplitude for
the process is asymptotically proportional to the sum of the squares of the
charges of quarks. The data are suggestive of models where quarks have unit
charges, or larger. Unequivocal tests could be made with the ILC or CLIC, but a
plasma wakefield e-e- collider might provide the most affordable option.


title: Magnetic Doppler Imaging of Active Stars

abstract:
  We present a new implementation of the magnetic Doppler imaging technique,
which aims at self-consistent temperature and magnetic mapping of the surface
structures in cool active stars. Our magnetic imaging procedure is unique in
its capability to model individual spectral features in all four Stokes
parameters. We discuss performance and intrinsic limitations of the new
magnetic Doppler imaging method. A special emphasis is given to the
simultaneous modelling of the magnetically sensitive lines in the optical and
infrared regions and to combining information from both atomic and molecular
spectral features. These two techniques may, for the first time, give us a tool
to study magnetic fields in the starspot interiors.


title: Electronic and structural transition in $La_{0.2} Sr_{0.8} Mn O_3$

abstract:
  We investigate the interplay of the electronic and structural transition in
La$_{0.2}$Sr$_{0.8}$MnO$_{3}$. The transport and specific heat measurements
exhibit unusual evolutions and signature of a first order phase transition
around 265 K. Mn K-edge extended $x$-ray absorption fine structure results
reveal distortion in the MnO$_6$ octahedra even in the cubic phase and a
remarkable evolution of the distortion across the phase transition. These
results manifest the importance of fluctuations in Mn 3$d$ orbital occupancy
and disorder in their electronic properties, which may help in understanding
the orbital and spin ordering proposed in these systems.


title:
Discrete series of representations for the modular double of
  U_q(sl(2,R))

abstract:
  Modular double of quantum group U_q (sl(2)) with deformation parameter
q=e^{i\pi\tau} is a natural object explicitly taking into account the duality
\tau -> 1/\tau. The use of the modular double in CFT allows to consider the
region 1<c<25 for the central charge of the Virasoro algebra when |\tau|=1. In
this paper a new discrete series of representations for the modular double of
U_q (sl(2,R)) is found for such \tau.


title:
Analytic approach to the ground state energy of charged anyon gases in
  the high magnetic field

abstract:
  We present analytic formulas for the ground state energy of the
two-dimensional (2D) anyon gas in the quantum limit of a perpendicular magnetic
field (Landau level filling factor \nu_L\le 1). These formulas, for the cases
without and with Coulomb interaction, are obtained by applying the harmonic
potential regularization for vanishing confinement to the harmonically confined
Coulomb anyon gas as in our previous paper for the case without magnetic field.
For the case without Coulomb interaction our analytic expression is exact. It
contains a contribution deriving from the anyon gauge field (characterizing the
fractional statistics by the anyon parameter \nu) and depends on \nu and \nu_L.
For the case with Coulomb interaction we introduce a function, depending on
\nu, \nu_L and the density parameter r_s, which is determined by fitting to the
interpolation formula of Fano and Ortolani in the fractional quantum Hall
regime for spin-polarized fermions in conjunction with results of Yoshioka for
the ground state energy of the 2D Coulomb boson gas in high magnetic fields.
With their dependence on \nu, our formulas apply not only to fermions (\nu=1)
but quite generally to anyons (0\le \nu\le 1).


title: Graph limits and exchangeable random graphs

abstract:
  We develop a clear connection between deFinetti's theorem for exchangeable
arrays (work of Aldous--Hoover--Kallenberg) and the emerging area of graph
limits (work of Lovasz and many coauthors). Along the way, we translate the
graph theory into more classical probability.


title:
Influence of global rotation and Reynolds number on the large-scale
  features of a turbulent Taylor-Couette flow

abstract:
  We experimentally study the turbulent flow between two coaxial and
independently rotating cylinders. We determined the scaling of the torque with
Reynolds numbers at various angular velocity ratios (Rotation numbers), and the
behaviour of the wall shear stress when varying the Rotation number at high
Reynolds numbers. We compare the curves with PIV analysis of the mean flow and
show the peculiar role of perfect counterrotation for the emergence of
organised large scale structures in the mean part of this very turbulent flow
that appear in a smooth and continuous way: the transition resembles a
supercritical bifurcation of the secondary mean flow.


title: Monitoring LMXBs with the Faulkes Telescopes

abstract:
  We have been undertaking a monitoring project of 13 low-mass X-ray binaries
(LMXBs) using FT North since early 2006. The introduction of FT South has
allowed us to extend this monitoring to include 15 southern hemisphere LMXBs.
With new instrumentation, we also intend to expand this monitoring to include
both infrared wavelengths and spectroscopy.


title: On Algebraic Graph Theory and the Dynamics of Innovation Networks

abstract:
  We investigate some of the properties and extensions of a dynamic innovation
network model recently introduced in
\citep{koenig07:_effic_stabil_dynam_innov_networ}. In the model, the set of
efficient graphs ranges, depending on the cost for maintaining a link, from the
complete graph to the (quasi-) star, varying within a well defined class of
graphs. However, the interplay between dynamics on the nodes and topology of
the network leads to equilibrium networks which are typically not efficient and
are characterized, as observed in empirical studies of R&D networks, by
sparseness, presence of clusters and heterogeneity of degree. In this paper, we
analyze the relation between the growth rate of the knowledge stock of the
agents from R&D collaborations and the properties of the adjacency matrix
associated with the network of collaborations. By means of computer simulations
we further investigate how the equilibrium network is affected by increasing
the evaluation time $\tau$ over which agents evaluate whether to maintain a
link or not. We show that only if $\tau$ is long enough, efficient networks can
be obtained by the selfish link formation process of agents, otherwise the
equilibrium network is inefficient. This work should assist in building a
theoretical framework of R&D networks from which policies can be derived that
aim at fostering efficient innovation networks.


title: Solution of the Pompeiu problem (II)

abstract: This paper has been withdrawn by the author.


title:
Observational constraints on AGB mass loss and its effect on AGB
  evolution

abstract:
  This review discusses some of the observational constraints on what we know
about the mass loss experienced by stars in the Asymptotic Giant Branch (AGB)
phase of evolution. Mass loss affects the maximum mass attained by the core of
an AGB star and hence its fate as a white dwarf or potentially a supernova. The
way mass loss depends on stellar initial parameters and time affects the yield
from AGB stars, in terms of elemental abundances and types of dust. The role of
pulsation, dust formation, chromospheres and other mechanisms which may
contribute to mass loss are assessed against observational evidence, and
suggestions are made for observations which could force significant new
progress in this field in the first decades of the 21st century. A better
understanding of AGB mass loss may be gained from a combination with studies of
first ascent red giant branch (RGB) stars and red supergiants, through
population studies and in different environments.


title: Directive Emission Obtained by Coordinate Transformation

abstract:
  We use coordinate transformation theory to realize substrates that can modify
the emission of an embedded source. Simulation results show that with proper
transformation functions the energy radiated by a source embedded in these
space variant media will be concentrated in a narrow beam. The thickness of the
slab achieved with our transformations will no longer be restricted by the
evanescent modes and the source can be placed at any position along the
boundary of the substrate without affecting the radiation pattern. We also
discuss the case where reduced parameters are used, which still performs well
and is physically realizable.


title:
Positive divisors on quotients of $\bar{M}_{0,n}$ and the Mori cone of
  $\bar{M}_{g,n}$

abstract:
  We prove that if $m \ge n-3$ then every $S_m$-invariant F-nef divisor on the
moduli space of stable $n$-pointed curves of genus zero is linearly equivalent
to an effective combination of boundary divisors. As an application, we
determine the Mori cone of the moduli spaces of stable curves of small genus
with few marked points.


title: Galaxies as a cosmological test

abstract:
  The relativistic LambdaCDM cosmological model has passed a demanding network
of tests that convincingly demonstrate it is a useful approximation to what
happened back to high redshift. But there are anomalies in its application to
structure formation on the scales of galaxies that show we have much to learn
about what this theory actually predicts and possibly something also of value
to learn about the fundamental theoretical basis for observational cosmology.
  This is slightly revised and enlarged from a contribution to A Century of
Cosmology, Venice, August 2007.


title:
Induction level determines signature of gene expression noise in
  cellular systems

abstract:
  Noise in gene expression, either due to inherent stochasticity or to varying
inter- and intracellular environment, can generate significant cell-to-cell
variability of protein levels in clonal populations. We present a theoretical
framework, based on stochastic processes, to quantify the different sources of
gene expression noise taking cell division explicitly into account. Analytical,
time-dependent solutions for the noise contributions arising from the major
steps involved in protein synthesis are derived. The analysis shows that the
induction level of the activator or transcription factor is crucial for the
characteristic signature of the dominant source of gene expression noise and
thus bridges the gap between seemingly contradictory experimental results.
Furthermore, on the basis of experimentally measured cell distributions, our
simulations suggest that transcription factor binding and promoter activation
can be modelled independently of each other with sufficient accuracy.


title:
Infrared and X-Ray Evidence for Circumstellar Grain Destruction by the
  Blast Wave of Supernova 1987A

abstract:
  Multiwavelength observations of supernova remnant (SNR) 1987A show that its
morphology and luminosity are rapidly changing at X-ray, optical, infrared, and
radio wavelengths as the blast wave from the explosion expands into the
circumstellar equatorial ring, produced by mass loss from the progenitor star.
The observed infrared (IR) radiation arises from the interaction of dust grains
that formed in mass outflow with the soft X-ray emitting plasma component of
the shocked gas. Spitzer IRS spectra at 5 - 30 microns taken on day 6190 since
the explosion show that the emission arises from ~ 1.1E-6 Msun of silicate
grains radiating at a temperature of ~180+20-15 K. Subsequent observations on
day 7137 show that the IR flux had increased by a factor of 2 while maintaining
an almost identical spectral shape. The observed IR-to-X-ray flux ratio (IRX)
is consistent with that of a dusty plasma with standard Large Magellanic Cloud
dust abundances. IRX has decreased by a factor of ~ 2 between days 6190 and
7137, providing the first direct observation of the ongoing destruction of dust
in an expanding SN blast wave on dynamic time scales. Detailed models
consistent with the observed dust temperature, the ionization timescale of the
soft X-ray emission component, and the evolution of IRX suggest that the
radiating silicate grains are immersed in a 3.5E6 K plasma with a density of
(0.3-1)E4 cm^{-3}, and have a size distribution that is confined to a narrow
range of radii between 0.023 and 0.22 microns. Smaller grains may have been
evaporated by the initial UV flash from the supernova.


title: The Nitrogen and Oxygen abundances in the neutral gas at high redshift

abstract:
  We study the Oxygen and Nitrogen abundances in the interstellar medium of
high-redshift galaxies. We use high resolution and high signal-to-noise ratio
spectra of Damped Lyman-alpha (DLA) systems detected along the line-of-sight to
quasars to derive robust abundance measurements from unsaturated metal
absorption lines. We present results for a sample of 16 high-redshift DLAs and
strong sub-DLAs (log N(HI)>19.5, 2.4<zabs<3.6) including 13 new measurements.
We find that the Oxygen to Iron abundance ratio is pretty much constant with
[O/Fe]=+0.32+-0.10 for -2.5<[O/H]<-1.0 with a small scatter around this value.
The Oxygen abundance follows quite well the Silicon abundance within 0.2dex
although the Silicon abundance could be slightly smaller for [O/H]<-2. The
distribution of the [N/O] abundance ratio, measured from components that are
detected in both species, is somehow double peaked: five systems have [N/O]>-1
and nine systems have [N/O]<-1.15. In the diagram [N/O] versus [O/H], a loose
plateau is possibly present at [N/O]=-0.9 that is below the so-called primary
plateau as seen in local metal-poor dwarf galaxies ([N/O] in the range -0.57 to
-0.74). No system is seen above this primary plateau whereas the majority of
the systems lie well below with a large scatter. All this suggests a picture in
which DLAs undergo successive star-bursts. During such an episode, the [N/O]
ratio decreases sharply because of the rapid release of Oxygen by massive stars
whereas inbetween two bursts, Nitrogen is released by low and intermediate-mass
stars with a delay and the [N/O] ratio increases.


title: Chiral phase transition in the presence of spinodal decomposition

abstract:
  The thermodynamics of a first order chiral phase transition is considered in
the presence of spinodal phase separation within the Nambu-Jona-Lasinio (NJL)
model. The properties of the basic thermodynamic observables in the coexistence
phase are discussed for zero and non-zero quark masses. We focus on observables
that probe the chiral phase transition. In particular, the behavior of the
specific heat and entropy as well as charge fluctuations are calculated and
analyzed. We show that the specific heat and charge susceptibilities diverge at
the isothermal spinodal lines. We determine the scaling behavior and compute
the critical exponent $\gamma$ of the net quark number susceptibility at the
isothermal spinodal lines within the NJL model and the Ginsburg-Landau theory.
We show that in the chiral limit the critical exponent $\gamma=1/2$ at the
tricritical point as well as along the isothermal spinodal lines. On the other
hand, for finite quark masses the critical exponent at the spinodal lines,
$\gamma=1/2$, differs from that at the critical end point, $\gamma=2/3$,
indicating a change in the universality class. These results are independent of
the particular choice of the chiral Lagrangian and should be common for all
mean field approaches.


title: Double fermionic contributions to the heavy-quark vacuum polarization

abstract:
  We compute the virtual O(\alpha_s^3 n_f^2) corrections to the heavy quark
vector current correlator in terms of expansions in the external momentum and
as an exact numerical solution. As a byproduct, the available high-energy
expansion at the three-loop level is extended.


title: The Inverse Amplitude Method and Adler Zeros

abstract:
  The Inverse Amplitude Method is a powerful unitarization technique to enlarge
the energy applicability region of Effective Lagrangians. It has been widely
used to describe resonances from Chiral Perturbation Theory as well as for the
Strongly Interacting Symmetry Breaking Sector. In this work we show how it can
be slightly modified to account also for the sub-threshold region,
incorporating correctly the Adler zeros required by chiral symmetry and
eliminating spurious poles. These improvements produce negligible effects on
the physical region.


title: Reduction Operators of Linear Second-Order Parabolic Equations

abstract:
  The reduction operators, i.e., the operators of nonclassical (conditional)
symmetry, of (1+1)-dimensional second order linear parabolic partial
differential equations and all the possible reductions of these equations to
ordinary differential ones are exhaustively described. This problem proves to
be equivalent, in some sense, to solving the initial equations. The ``no-go''
result is extended to the investigation of point transformations (admissible
transformations, equivalence transformations, Lie symmetries) and Lie
reductions of the determining equations for the nonclassical symmetries.
Transformations linearizing the determining equations are obtained in the
general case and under different additional constraints. A nontrivial example
illustrating applications of reduction operators to finding exact solutions of
equations from the class under consideration is presented. An observed
connection between reduction operators and Darboux transformations is
discussed.


title: Anyon related correlations in two-dimensional Coulomb gases

abstract:
  In our recent paper (Phys. Rev. B 76, 075403 (2007)), we have applied the
anyon concept to derive an approximate analytic formula for the ground state
energy, which applies to two-dimensional (2D) Coulomb systems from the bosonic
to the fermionic limit. We make use of these results here to draw attention to
correlation effects for two special cases: the spin-polarized 2D fermion system
and the charged anyon system close to the bosonic limit. By comparison with
quantum Monte-Carlo data (for the former) and exact results obtained in the
hypernetted-chain and Bogolyubov approximations (for the latter) we can
conclude on correlation effects, which have their origin in the bosonic systems
and come into play by using the anyon concept. To our knowledge, these
correlations are not yet considered in the literature.


title: Variational calculus with constraints on general algebroids

abstract:
  Variational calculus on a vector bundle E equipped with a structure of a
general algebroid is developed, together with the corresponding analogs of
Euler-Lagrange equations. Constrained systems are introduced in the variational
and in the geometrical setting. The constrained Euler-Lagrange equations are
derived for analogs of holonomic, vakonomic and nonholonomic constraints. This
general model covers majority of first-order Lagrangian systems which are
present in the literature and reduces to the standard variational calculus and
the Euler-Lagrange equations in Classical Mechanics for E=TM.


title: Mesoscopic photon heat transistor

abstract:
  We show that the heat transport between two bodies, mediated by
electromagnetic fluctuations, can be controlled with an intermediate quantum
circuit - leading to the device concept Mesoscopic Photon Heat Transistor
(MPHT). Our theoretical analysis is based on a novel Meir-Wingreen-Landauer
type of conductance formula, which gives the photonic heat current through an
arbitrary circuit element coupled to two dissipative reservoirs at finite
temperatures. As an illustration we present an exact solution for the case when
the intermediate circuit can be described as an electromagnetic resonator. We
discuss in detail how the MPHT can be implemented experimentally in terms of a
flux-controlled SQUID circuit.


title: Electrostatic charging of non-polar colloids by reverse micelles

abstract:
  Colloids dispersed in a non-polar solvent become charged when reverse
micelles are added. We study the charge of individual sterically-stabilized
poly(methyl methacrylate) spheres dispersed in micellar solutions of the
surfactants sodium bis(2-ethyl 1-hexyl) sulfosuccinate [AOT], zirconyl 2-ethyl
hexanoate [Zr(Oct)$_{2}$], and a copolymer of poly(12-hydroxystearic
acid)--poly(methyl methacrylate) [PHSA-PMMA]. Although the sign of the particle
charge is positive for Zr(Oct)$_{2}$, negative for AOT, and essentially neutral
for PHSA-PMMA the different micellar systems display a number of common
features. In particular, we demonstrate that, over a wide range of
concentrations, the colloid charge is independent of the number of micelles
added and scales linearly with the colloid size. A simple thermodynamic model,
in which the particle charge is generated by the competitive adsorption of both
positive and negative micelles, is in good agreement with the experimental
data.


title: Many-Particle Quantum Cosmology

abstract:
  The Einstein-Friedmann Universe as whole quantum object can be treated as
bosonic string mass groundstate, called a tachyon, having negative mass square
and a speed more than the speed of light. I present a brief review of results
obtained from this point of view called Many-Particle Quantum Gravity approach
- the monodromy problem in the Fock space, thermodynamics of the Universe, and
the extremal tachyon mass model.


title: Automatic generation of quarkonium amplitudes in NRQCD

abstract:
  We present a simple method to automatically evaluate arbitrary tree-level
amplitudes involving the production or decay of a heavy quark pair QQbar in a
generic {2S+1}L_J^[1,8] state, i.e., the short distance coefficients appearing
in the NRQCD factorization formalism. Our approach is based on extracting the
relevant contributions from the open heavy quark-antiquark amplitudes through
an expansion with respect to the quark-antiquark relative momentum and the
application of suitable color and spin projectors. To illustrate the
capabilities of the method and its implementation in MadGraph a few
applications to quarkonium collider phenomenology are presented.


title: Analysis of Kelly-optimal portfolios

abstract:
  We investigate the use of Kelly's strategy in the construction of an optimal
portfolio of assets. For lognormally distributed asset returns, we derive
approximate analytical results for the optimal investment fractions in various
settings. We show that when mean returns and volatilities of the assets are
small and there is no risk-free asset, the Kelly-optimal portfolio lies on
Markowitz Efficient Frontier. Since in the investigated case the Kelly approach
forbids short positions and borrowing, often only a small fraction of the
available assets is included in the Kelly-optimal portfolio. This phenomenon,
that we call condensation, is studied analytically in various model scenarios.


title: Low temperature mean opacities for the carbon-rich regime

abstract:
  Asymptotic Giant Branch (AGB) stars undergo a change in their chemical
composition during their evolution. This in turn leads to an alteration of the
radiative opacities, especially in the cool layers of the envelope and the
atmosphere, where molecules are the dominant opacity sources. A key parameter
in this respect is the number ratio of carbon to oxygen atoms (C/O). In terms
of low temperature mean opacities, a variation of this parameter usually cannot
be followed in stellar evolution models, because up to now tabulated values
were only available for scaled solar metal mixtures (with C/O ~ 0.5). We thus
present a set of newly generated tables containing Rosseland mean opacity
coefficients covering both the oxygen-rich (C/O < 1) and the carbon-rich (C/O >
1) regime. We compare our values to existing tabular data and investigate the
relevant molecular opacity contributors.


title:
Middleware-based Database Replication: The Gaps between Theory and
  Practice

abstract:
  The need for high availability and performance in data management systems has
been fueling a long running interest in database replication from both academia
and industry. However, academic groups often attack replication problems in
isolation, overlooking the need for completeness in their solutions, while
commercial teams take a holistic approach that often misses opportunities for
fundamental innovation. This has created over time a gap between academic
research and industrial practice.
  This paper aims to characterize the gap along three axes: performance,
availability, and administration. We build on our own experience developing and
deploying replication systems in commercial and academic settings, as well as
on a large body of prior related work. We sift through representative examples
from the last decade of open-source, academic, and commercial database
replication systems and combine this material with case studies from real
systems deployed at Fortune 500 customers. We propose two agendas, one for
academic research and one for industrial R&D, which we believe can bridge the
gap within 5-10 years. This way, we hope to both motivate and help researchers
in making the theory and practice of middleware-based database replication more
relevant to each other.


title: Interaction of streamers in air and other oxygen-nitrogen mixtures

abstract:
  The interaction of streamers in nitrogen-oxygen mixtures such as air is
studied. First, an efficient method for fully three-dimensional streamer
simulations in multiprocessor machines is introduced. With its help, we find
two competing mechanisms how two adjacent streamers can interact: through
electrostatic repulsion and through attraction due to nonlocal
photo-ionization. The non-intuitive effects of pressure and of the
nitrogen-oxygen ratio are discussed. As photo-ionization is experimentally
difficult to access, we finally suggest to measure it indirectly through
streamer interactions.


title: Evidence for Tadpole Cancellation in the Topological String

abstract:
  We study the topological string on compact Calabi-Yau threefolds in the
presence of orientifolds and D-branes. In examples, we find that the total
topological string amplitude admits a BPS expansion only if the topological
charge of the D-brane is equal to that of the orientifold plane. We interpret
this as a manifestation of a general tadpole cancellation condition in the
topological string that is necessary for decoupling of A- and B-model in loop
amplitudes. Our calculations in the A-model involve an adapted version of
existing localization techniques, and give predictions for the real enumerative
geometry of higher genus curves in Calabi-Yau manifolds. In the B-model, we
introduce an extension of the holomorphic anomaly equation to unoriented
strings.


title: Molecular tracers of high mass star-formation in external galaxies

abstract:
  Hot core molecules should be detectable in external active galaxies out to
high redshift. We present here a detailed study of the chemistry of
star-forming regions under physical conditions that differ significantly from
those likely to be appropriate in the Milky Way Galaxy. We examine, in
particular, the trends in molecular abundances as a function of time with
respect to changes in the relevant physical parameters. These parameters
include metallicity, dust:gas mass ratio, the H$_{2}$ formation rate, relative
initial elemental abundances, the cosmic ray ionization rate, and the
temperature of hot cores. These trends indicate how different tracers provide
information on the physical conditions and on evolutionary age. We identify hot
core tracers for several observed galaxies that are considered to represent
spirals, active galaxies, low-metallicity galaxies, and high-redshift galaxies.
Even in low-metallicity examples, many potential molecular tracers should be
present at levels high enough to allow unresolved detection of active galaxies
at high redshift containing large numbers of hot cores.


title: Emergence of a Big Bang singularity in an exact string background

abstract:
  The origin of Big Bang singularity in 3+1 dimensions can be understood in an
exact string theory background obtained by an analytic continuation of a cigar
like geometry with a nontrivial dilaton. In a T-dual conformal field theory
picture there exists a closed string tachyon potential which excises the
singular space-time of a strongly coupled regime to ensure that a higher
dimensional universe has no curvature singularity. However in 3+1 dimensions
the universe exhibits all the pathology of a standard Big Bang cosmology. The
emergence of a singularity now owes to a higher dimensional orbifold
singularity which does not have a curvature singularity in higher dimensions,
suggesting that close to the compactification scale an effective description of
3+1 dimensions breaks down and bouncing universe emerges in 5 and higher
dimensions.


title: Unification per the Relational Blockworld

abstract:
  We use the Relational Blockworld (RBW) interpretation of quantum mechanics to
resolve the foundational problems therein. As predicted by Smolin, the
resolution of these problems is not independent of the problem of unification
and the nature of time. Specifically, RBW requires a theory fundamental to
quantum physics in which one must explicitly construct dynamical/diachronic
entities (objects obtained via trans-temporal identification) from 'relations'.
We use discrete graph theory to propose heuristically the nature of this
underlying theory, which is based on a self-consistency criterion for the
mutual construct of dynamical/diachronic entities, space and time whence a
spatiotemporally discrete action fundamental to the path integral approach to
quantum and classical physics. The proposed unification scheme suggests a novel
approach to quantum gravity.


title: Modeling Evolving Innovation Networks

abstract:
  We develop a new framework for modeling innovation networks which evolve over
time. The nodes in the network represent firms, whereas the directed links
represent unilateral interactions between the firms. Both nodes and links
evolve according to their own dynamics and on different time scales. The model
assumes that firms produce knowledge based on the knowledge exchange with other
firms, which involves both costs and benefits for the participating firms. In
order to increase their knowledge production, firms follow different strategies
to create and/or to delete links with other firms. Dependent on the information
firms take into account for their decision, we find the emergence of different
network structures. We analyze the conditions for the existence of these
structures within a mathematical approach and underpin our findings by
extensive computer simulations which show the evolution of the networks and
their equilibrium state. In the discussion of the results, particular attention
is given to the emergence of direct and indirect reciprocity in knowledge
exchange, which refers to the emergence of cycles in the network structure. In
order to motivate our modeling framework, in the first part of the chapter we
give a broad overview of existing literature from economics and physics. This
shows that our framework bridges and extends two different lines of research,
namely the study of equilibrium networks with simple topologies and the dynamic
approach of hypercycle models.


title:
Dynamical Simulations of Magnetically Channeled Line-Driven Stellar
  Winds: II. The Effects of Field-Aligned Rotation

abstract:
  Building upon our previous MHD simulation study of magnetic channeling in
radiatively driven stellar winds, we examine here the additional dynamical
effects of stellar {\em rotation} in the (still) 2-D axisymmetric case of an
aligned dipole surface field. In addition to the magnetic confinement parameter
$\eta_{\ast}$ introduced in Paper I, we characterize the stellar rotation in
terms of a parameter $W \equiv V_{\rm{rot}}/V_{\rm{orb}}$ (the ratio of the
equatorial surface rotation speed to orbital speed), examining specifically
models with moderately strong rotation $W =$ 0.25 and 0.5, and comparing these
to analogous non-rotating cases. Defining the associated Alfv\'{e}n radius
$R_{\rm{A}} \approx \eta_{\ast}^{1/4} \Rstar$ and Kepler corotation radius
$R_{\rm{K}} \approx W^{-2/3} \Rstar$, we find rotation effects are weak for
models with $R_{\rm{A}} < R_{\rm{K}}$, but can be substantial and even dominant
for models with $R_{\rm{A}} \gtwig R_{\rm{K}}$. In particular, by extending our
simulations to magnetic confinement parameters (up to $\eta_{\ast} = 1000$)
that are well above those ($\eta_{\ast} = 10$) considered in Paper I, we are
able to study cases with $R_{\rm{A}} \gg R_{\rm{K}}$; we find that these do
indeed show clear formation of the {\em rigid-body} disk predicted in previous
analytic models, with however a rather complex, dynamic behavior characterized
by both episodes of downward infall and outward breakout that limit the buildup
of disk mass. Overall, the results provide an intriguing glimpse into the
complex interplay between rotation and magnetic confinement, and form the basis
for a full MHD description of the rigid-body disks expected in strongly
magnetic Bp stars like $\sigma$ Ori E.


title:
Erratum (astro-ph/0510172): Robust Limits on Lorentz Violation from
  Gamma-Ray Bursts

abstract:
  We correct the fitting formula used in refs. [1,2] to obtain a robust limit
on a violation of Lorentz invariance that depends linearly on the photon
energy. The correction leads to a slight increase of the limit on the scale of
the violation, to M > 1.4 x 10^{16} GeV.


title:
Correlation of optical conductivity and ARPES spectra of strong-coupling
  large polarons and its display in cuprates

abstract:
  Common approach is used to calculate band due to strong-coupling large
polaron (SCLP) photodissociation in ARPES and in optical conductivity (OC)
spectra. It is based on using the coherent-states representation for the phonon
field in SCLP. The calculated positions of both band maximums are universal
functions of one parameter - the SCLP binding energy Ep: ARPES band maximum
lies at binding energy about 3.2Ep; the OC band maximum is at the photon energy
about 4.2Ep. The half-widths of the bands are mainly determined by Ep and
slightly depend on Frohlich electron-phonon coupling constant: for its value
6-8 the ARPES band half-width is 1.7-1.3Ep and the OC band half-width is
2.8-2.2Ep. Using these results one can predict approximate position of ARPES
band maximum and half-width from the maximum of mid-IR OC band and vice versa.
Comparison of the results with experiments leads to a conclusion that
underdoped cuprates contain SCLPs with Ep=0.1-0.2 eV that is in good conformity
with the medium parameters in cuprates. The values of the polaron binding
energy determined from experimental ARPES and OC spectra of the same material
are in good conformity too: the difference between them is within 10 percent.


title:
Orbital diamagnetism in multilayer graphenes: Systematic study with the
  effective mass approximation

abstract:
  We present a theoretical study on the orbital magnetism in multilayer
graphenes within the effective mass approximation. The Hamiltonian and thus
susceptibility can be decomposed into contributions from sub-systems equivalent
to monolayer or bilayer graphene. The monolayer-type subband exists only in odd
layers and exhibits a delta-function susceptibility at $E_F=0$. The
bilayer-type subband appearing in every layer number gives a singular structure
in the vicinity of $E_F=0$ due to the trigonal warping as well as a logarithmic
tail away from $E_F=0$. The integral of the susceptibility over energy is
approximately given only by the layer number.


title:
Generation of indistinguishable and pure heralded single photons with
  tunable bandwidth

abstract:
  We describe a new scheme to fully control the joint spectrum of paired
photons generated in spontaneous parametric down-conversion. We show the
capability of this method to generate frequency-uncorrelated photon pairs that
are pure and indistinguishable, and whose bandwidth can be readily tuned.
Importantly, the scheme we propose here can be implemented in any nonlinear
crystal and frequency band of interest.


title:
A lower bound for the eigenvalues of the Sen-Witten operator on closed
  spacelike hypersurfaces

abstract:
  The eigenvalue problem for the Sen--Witten operator on closed spacelike
hypersurfaces is investigated. The (square of its) eigenvalues are shown to be
given exactly by the 3-surface integral appearing in the expression of the
total energy-momentum of the matter+gravity systems in Witten's energy
positivity proof. A sharp lower bound for the eigenvalues, given in terms of
the constraint parts of the spacetime Einstein tensor, i.e. the energy and
momentum densities of the matter fields, is given.


title: Dressed Domain Walls and Holography

abstract:
  The cutoff version of the AdS/CFT correspondence states that the Randall
Sundrum scenario is dual to a Conformal Field Theory (CFT) coupled to gravity
in four dimensions. The gravitational field produced by relativistic domain
walls can be exactly solved in both sides of the correspondence, and thus
provides one further check of it. We show in the two sides that for the most
symmetric case, the wall motion does not lead to particle production of the CFT
fields. Still, there are nontrivial effects. Due to the trace anomaly, the CFT
effectively renormalizes the domain wall tension. On the five dimensional side,
the wall is a codimension 2 brane localized on the Randall-Sundrum brane, which
pulls the wall in a uniform acceleration. This is perceived from the brane as a
domain wall with a tension slightly larger than its bare value. In both cases,
the deviation from General Relativity appears at nonlinear level in the source,
and the leading corrections match to the numerical factors.


title: Lifetime and decay of unstable particles in strong gravitational fields

abstract:
  We consider here the decay of unstable particles in geodesic circular motion
around compact objects. For the neutron, in particular, strong and weak decay
are calculated by means of a semiclassical approach. Noticeable effects are
expected to occur as one approaches the photonic circular orbit of realistic
black-holes. We argue that, in such a limit,the quasi-thermal spectrum inherent
to extremely relativistic observers in circular motion plays a role similar to
the Unruh radiation for uniformly accelerated observers.


title:
Regularity of radial minimizers of reaction equations involving the
  p-Laplacian

abstract:
  We consider semi-stable, radially symmetric, and decreasing solutions of a
reaction equation involving the p-Laplacian, where the reaction term is a
locally Lipschitz function, and the domain is the unit ball. For this class of
radial solutions, which includes local minimizers, we establish pointwise and
Sobolev estimates which are optimal and do not depend on the specific nonlinear
reaction term. Under standard assumptions we also prove the regularity of the
corresponding extremal solution.


title: Trading in Risk Dimensions (TRD)

abstract:
  Previous work, mostly published, developed two-shell recursive trading
systems. An inner-shell of Canonical Momenta Indicators (CMI) is adaptively fit
to incoming market data. A parameterized trading-rule outer-shell uses the
global optimization code Adaptive Simulated Annealing (ASA) to fit the trading
system to historical data. A simple fitting algorithm, usually not requiring
ASA, is used for the inner-shell fit. An additional risk-management
middle-shell has been added to create a three-shell recursive
optimization/sampling/fitting algorithm. Portfolio-level distributions of
copula-transformed multivariate distributions (with constituent markets
possessing different marginal distributions in returns space) are generated by
Monte Carlo samplings. ASA is used to importance-sample weightings of these
markets.
  The core code, Trading in Risk Dimensions (TRD), processes Training and
Testing trading systems on historical data, and consistently interacts with
RealTime trading platforms at minute resolutions, but this scale can be
modified. This approach transforms constituent probability distributions into a
common space where it makes sense to develop correlations to further develop
probability distributions and risk/uncertainty analyses of the full portfolio.
ASA is used for importance-sampling these distributions and for optimizing
system parameters.


title:
Self-assembly, structure and electronic properties of a quasiperiodic
  lead monolayer

abstract:
  A quasiperiodic Pb monolayer has been formed on the five-fold surface of the
Al-Pd-Mn quasicrystal. Growth of the monolayer proceeds via self-assembly of an
interconnected network of pentagonal Pb stars, which are shown to be
tau-inflated compared to similar structural elements of the quasiperiodic
substrate. Measurements of the electronic structure of the system using
scanning tunnelling spectroscopy and ultra-violet photoemission spectroscopy
reveal that the Pb monolayer displays a pseudo-gap at the Fermi level which is
directly related to its quasiperiodic structure.


title: X-Ray Flaring on the dMe Star, Ross 154

abstract:
  We present results from two Chandra imaging observations of Ross 154, a
nearby flaring M dwarf star. During a 61-ks ACIS-S exposure, a very large flare
occurred (the equivalent of a solar X3400 event, with L_X = 1.8x10^30 ergs/s)
in which the count rate increased by a factor of over 100. The early phase of
the flare shows evidence for the Neupert effect, followed by a further rise and
then a two-component exponential decay. A large flare was also observed at the
end of a later 48-ks HRC-I observation. Emission from the non-flaring phases of
both observations was analyzed for evidence of low level flaring. From these
temporal studies we find that microflaring probably accounts for most of the
`quiescent' emission, and that, unlike for the Sun and the handful of other
stars that have been studied, the distribution of flare intensities does not
appear to follow a power-law with a single index. Analysis of the ACIS spectra,
which was complicated by exclusion of the heavily piled-up source core,
suggests that the quiescent Ne/O abundance ratio is enhanced by a factor of
~2.5 compared to the commonly adopted solar abundance ratio, and that the Ne/O
ratio and overall coronal metallicity during the flare appear to be enhanced
relative to quiescent abundances. Based on the temperatures and emission
measures derived from the spectral fits, we estimate the length scales and
plasma densities in the flaring volume and also track the evolution of the
flare in color-intensity space. Lastly, we searched for a stellar-wind
charge-exchange X-ray halo around the star but without success; because of the
relationship between mass-loss rate and the halo surface brightness, not even
an upper limit on the stellar mass-loss rate can be determined.


title: The copies of any permutation pattern are asymptotically normal

abstract:
  We prove that the number of copies of any given permutation pattern $q$ has
an asymptotically normal distribution in random permutations.


title: B-L Conserved Baryogenesis

abstract:
  In the presence of anomaly induced sphaleron process, only a B-L asymmetry
can be partially converted to the baryon asymmetry while any B+L asymmetry
would be completely erased. Thus in any successful baryogenesis theories, B-L
is usually violated above the electroweak scale to explain the observed
matter-antimatter asymmetry of the universe. However, if any lepton asymmetry
is not affected by the sphaleron processes, a B-L conserved theory can still
realize the baryogenesis. We present here an SU(5) GUT realization of this
scenario, which naturally accommodates small masses of Dirac neutrinos.


title: Some Progress in Conformal Geometry

abstract:
  This is a survey paper of our current research on the theory of partial
differential equations in conformal geometry. Our intention is to describe some
of our current works in a rather brief and expository fashion. We are not
giving a comprehensive survey on the subject and references cited here are not
intended to be complete. We introduce a bubble tree structure to study the
degeneration of a class of Yamabe metrics on Bach flat manifolds satisfying
some global conformal bounds on compact manifolds of dimension 4. As
applications, we establish a gap theorem, a finiteness theorem for
diffeomorphism type for this class, and diameter bound of the
$\sigma_2$-metrics in a class of conformal 4-manifolds. For conformally compact
Einstein metrics we introduce an eigenfunction compactification. As a
consequence we obtain some topological constraints in terms of renormalized
volumes.


title: The seeds of cosmic structures as a door to Quantum Gravity Phenomena

abstract:
  This paper contains a critique of the standard inflationary account of the
origin of cosmological structures from quantum fluctuations in the early
universe. This critique can be thought to be purely philosophical in nature,
but I prefer to view it, rather, as arising from the need to put the
interpretational aspects of the theory -which quite obviously lie at the basis
of any comparison with experiments- on the firm grounds required by the unique
features of the problem at hand. This discussion is followed by a proposal to
complement that treatment to deal with the unsatisfactory aspects of the
standard account of the problem, using Penrose's ideas about the quantum
gravity induced collapse of the quantum states of matter fields. The formalism
developed to carry out this analysis was first introduced in [1] and leads to
unexpected predictions and to novel avenues to confront some of the details of
the proposal with observations. In my view, this is, therefore, the most
promising path towards quantum gravity phenomenology.


title: Central cross-sections make surfaces of revolution quadric

abstract:
  We prove here that when all planes transverse and nearly perpendicular to the
axis of a surface of revolution intersect it in loops having central symmetry,
the surface must be quadric. It follows that the quadrics are the only surfaces
of revolution without skewloops. Similar statements hold for hypersurfaces of
revolution in higher dimensions.


title:
Charge pumping and noise in a one-dimensional wire with weak
  electron-electron interactions

abstract:
  We consider the adiabatic pumping of charge through a mesoscopic one
dimensional wire in the presence of electron-electron interactions. A two-delta
potential model is used to describe the wire, which allows to obtain exactly
the scattering matrix coefficients, which are renormalized by the interactions.
Two periodic drives, shifted one from another, are applied at two locations of
the wire in order to drive a current through it in the absence of bias.
Analytical expressions are obtained for the pumped charge, current noise, and
Fano factor in different regimes. This allows to explore pumping for the whole
parameter range of pumping strengths. We show that, working close to a
resonance is necessary to have a comfortable window of pumping amplitudes where
charge quantization is close to the optimum value: a single electron charge is
transferred in one cycle. Interactions can improve the situation, the charge
$Q$ is closer to one electron charge and noise is reduced, following a $Q
(1-Q)$ behavior, reminiscent of the reduction of noise in quantum wires by $T
(1-T)$, where $T$ is the energy transmission coefficient. For large pumping
amplitudes, this charge vanishes, noise also decreases but slower than the
charge.


title:
A convergent Finite Element-Finite Volume scheme for the compressible
  Stokes problem Part I -- the isothermal case

abstract:
  In this paper, we propose a discretization for the (nonlinearized)
compressible Stokes problem with a linear equation of state $\rho=p$, based on
Crouzeix-Raviart elements. The approximation of the momentum balance is
obtained by usual finite element techniques. Since the pressure is piecewise
constant, the discrete mass balance takes the form of a finite volume scheme,
in which we introduce an upwinding of the density, together with two additional
stabilization terms. We prove {\em a priori} estimates for the discrete
solution, which yields its existence by a topological degree argument, and then
the convergence of the scheme to a solution of the continuous problem.


title: Spectral imbalance and the normalized dissipation rate of turbulence

abstract:
  The normalized turbulent dissipation rate $C_\epsilon$ is studied in decaying
and forced turbulence by direct numerical simulations, large-eddy simulations,
and closure calculations. A large difference in the values of $C_\epsilon$ is
observed for the two types of turbulence. This difference is found at moderate
Reynolds number, and it is shown that it persists at high Reynolds number,
where the value of $C_\epsilon$ becomes independent of the Reynolds number, but
is still not unique. This difference can be explained by the influence of the
nonlinear cascade time that introduces a spectral disequilibrium for
statistically nonstationary turbulence. Phenomenological analysis yields simple
analytical models that satisfactorily reproduce the numerical results. These
simple spectral models also reproduce and explain the increase of $C_\epsilon$
at low Reynolds number that is observed in the simulations.


title: Heteroclinic Travelling Waves of Gradient Diffusion Systems

abstract:
  We establish existence of travelling waves to the gradient system $u_t =
u_{zz} - \nabla W(u)$ connecting two minima of $W$ when $u : \R \times
(0,\infty) \larrow \R^N$, that is, we establish existence of a pair $(U,c) \in
[C^2(\R)]^N \by (0,\infty)$, satisfying \[ \{{array}{l}
  U_{xx} - \nabla W (U) = - c U_x
  U(\pm \infty) = a^{\pm}, {array}. \] where $a^{\pm}$ are local minima of the
potential $W \in C_{\textrm{loc}}^2(\R^N)$ with $W(a^-)< W(a^+)=0$ and $N \geq
1$. Our method is variational and based on the minimization of the functional
$E_c (U) = \int_{\R}\Big\{{1/2}|U_x|^2 + W(U) \Big\}e^{cx} dx$ in the
appropriate space setup. Following Alikakos-Fusco \cite{A-F}, we introduce an
artificial constraint to restore compactness and force the desired asymptotic
behavior, which we later remove. We provide variational characterizations of
the travelling wave and the speed. In particular, we show that $E_c(U)=0$.


title: Dynamics of spectrally truncated inviscid turbulence

abstract:
  The evolution of the turbulent energy spectrum for the inviscid spectrally
truncated Euler equations is studied by closure calculations. The observed
behavior is similar to the one found in direct numerical simulations
[Cichowlas, Bona\"ititi, Debbasch, and Brachet, Phys. Rev. Lett. 95, 264502
(2005)]. A Kolmogorov spectral range and an equipartition range are observed
simultaneously. Between these two ranges a "quasi-dissipative" zone is present
in the kinetic energy spectrum. The time evolution of the wave number that
marks the beginning of the equipartition range is analyzed and it is shown that
spectral nonlocal interactions are governing this evolution.


title: Seiberg-Witten Theory and Extended Toda Hierarchy

abstract:
  The quasiclassical solution to the extended Toda chain hierarchy,
corresponding to the deformation of the simplest Seiberg-Witten theory by all
descendants of the dual topological string model, is constructed explicitly in
terms of the complex curve and generating differential. The first derivatives
of prepotential or quasiclassical tau-function over the extra times, extending
the Toda chain, are expressed through the multiple integrals of the
Seiberg-Witten one-form. We derive the corresponding quasiclassical Virasoro
constraints, discuss the functional formulation of the problem and propose
generalization of the extended Toda hierarchy to the nonabelian theory.


title: Transversely non simple knots

abstract:
  By proving a connected sum formula for the Legendrian invariant $\lambda_+$
in knot Floer homology we exhibit infinitely many transversely non simple
knots.


title: Nestings of Matchings and Permutations and North Steps in PDSAWs

abstract:
  We present a simple bijective proof of the fact that matchings of [2n] with N
nestings are equinumerous to partially directed self avoiding walks confined to
the symmetric wedge defined by y=+-x, with n east steps and N north steps. A
very similar construction connects permutations with N nestings and PDSAWs
remaining below the x-axis, again with N north steps. Furthermore, both
bijections transport several combinatorially meaningful parameters.


title: Spin polarization in modulation-doped GaAs quantum wires

abstract:
  We study spin polarization in a split-gate quantum wire focussing on the
effect of a realistic smooth potential due to remote donors. Electron
interaction and spin effects are included within the density functional theory
in the local spin density approximation. We find that depending on the electron
density, the spin polarization exhibits qualitatively different features. For
the case of relatively high electron density, when the Fermi energy $E_{F}$
exceeds a characteristic strength of a long-range impurity potential
$V_{donors}$, the density spin polarization inside the wire is practically
negligible and the wire conductance is spin-degenerate. When the density is
decreased such that $E_{F}$ approaches $V_{donors}$, the electron density and
conductance quickly become spin polarized. With further decrease of the density
the electrons are trapped inside the lakes (droplets) formed by the impurity
potential and the wire conductance approaches the pinch-off regime. We discuss
the limitations of DFT-LSDA in this regime and compare the obtained results
with available experimental data.


title:
Development of CMOS monolithic pixel sensors with in-pixel correlated
  double sampling and fast readout for the ILC

abstract:
  This paper presents the design and results of detailed tests of a CMOS active
pixel chip for charged particle detection with in-pixel charge storage for
correlated double sampling and readout in rolling shutter mode at frequencies
up to 25 MHz. This detector is developed in the framework of R&D for the Vertex
Tracker for the International Linear Collider.


title:
Statistical studies of random lasing modes and amplified spontaneous
  emission spikes in weakly scattering systems

abstract:
  We measured the ensemble-averaged spectral correlation functions and
statistical distributions of spectral spacing and intensity for lasing modes in
weakly scattering systems, and compared them to those of the amplified
spontaneous emission spikes. Their dramatic differences illustrated the
distinct physical mechanisms. Our numerical simulation revealed that even
without reabsorption the number of potential lasing modes might be greatly
reduced by local excitation of a weakly scattering system. The lasing modes
could be drastically different from the quasimodes of the passive system due to
selective amplification of the feedback from the scatterers within the local
gain region.


title: A first-order formalism for timelike and spacelike brane solutions

abstract:
  We show that the construction of BPS-type equations for non-extremal black
holes due to Miller et. al. can be extended to branes of arbitrary dimension
and, more importantly, to time-dependent solutions. We call these first-order
equations fake- or pseudo-BPS equations in light of the formalism that has been
developed for domain wall and cosmological solutions of gravity coupled to
scalar fields. We present the fake/pseudo-BPS equations for all stationary
branes (timelike branes) and all time-dependent branes (spacelike branes) of an
Einstein-dilaton-p-form system in arbitrary dimensions.


title:
On the absence of shear from perfect Einstein rings and the stability of
  geometry

abstract:
  Concordance cosmology points to a Universe of zero mean curvature, due to the
inflation mechanism which occurred soon after the Big Bang, while along a
relatively small number of lower redshift light paths where lensing events are
observed, space is positively curved. How do we know that global geometry and
topology are robust rather than in a state of chaos? The phenomenon of cosmic
shear provides an effective way of mapping curvature fluctuations, because it
affects {\it any} light rays whether they intercept mass clumps or not. We
discuss a range of astrophysical applications of the principal manifestation of
shear - the distortion of images. It will be shown that the quickest way of
testing the existence of shear in the near Universe is to look at the shape of
Einstein rings. The fact that most of these rings are circular to a large
extent means, statistically speaking, shear occurs at a much lower level than
the expectation based upon our current understanding of the inhomogeneous
Universe. While inflation may account for the mean geometry, it offers no means
of stabilizing it against the fluctuations caused by non-linear matter clumping
at low redshift. Either this clumping is actually much less severe, or the
physical mechanism responsible for shaping the large scale curvature has been
active not only during the very early epochs, but also at all subsequent times.
Might it be the vital `interface' between expansion on Hubble distances and
gravity on cluster scales and beneath?