title: Adiabatic Quantum Counting by Geometric Phase Estimation

abstract:
  We design an adiabatic quantum algorithm for the counting problem, i.e.,
approximating the proportion, $\alpha$, of the marked items in a given
database. As the quantum system undergoes a designed cyclic adiabatic
evolution, it acquires a Berry phase $2\pi\alpha$. By estimating the Berry
phase, we can approximate $\alpha$, and solve the problem. For an error bound
$\epsilon$, the algorithm can solve the problem with cost of order
$(\frac{1}{\epsilon})^{3/2}$, which is not as good as the optimal algorithm in
the quantum circuit model, but better than the classical random algorithm.
Moreover, since the Berry phase is a purely geometric feature, the result may
be robust to decoherence and resilient to certain noise.


title:
Prospects for Improving the Intrinsic and Extrinsic Properties of
  Magnesium Diboride Superconducting Strands

abstract:
  The magnetic and transport properties of magnesium diboride films represent
performance goals yet to be attained by powder-processed bulk samples and
conductors. Such performance limits are still out of the reach of even the best
magnesium diboride magnet wire. In discussing the present status and prospects
for improving the performance of powder-based wire we focus attention on (1)
the intrinsic (intragrain) superconducting properties of magnesium diboride,
Hc2 and flux pinning, (2) factors that control the efficiency with which
current is transported from grain-to-grain in the conductor, an extrinsic
(intergrain) property. With regard to Item-(1), the role of dopants in Hc2
enhancement is discussed and examples presented. On the other hand their roles
in increasing Jc, both via Hc2 enhancement as well as direct
fluxoid/pining-center interaction, are discussed and a comprehensive survey of
Hc2 dopants and flux-pinning additives is presented. Current transport through
the powder-processed wire (an extrinsic property) is partially blocked by the
inherent granularity of the material itself and the chemical or other
properties of the intergrain surfaces. These and other such results indicate
that in many cases less than 15% of the conductor's cross sectional area is
able to carry transport current. It is pointed out that densification in
association with the elimination of grain-boundary blocking phases would yield
five-to ten-fold increases in Jc in relevant regimes, enabling the performance
of magnesium diboride in selected applications to compete with that of Nb-Sn.


title:
The Finite Non-periodic Toda Lattice: A Geometric and Topological
  Viewpoint

abstract:
  In 1967, Japanese physicist Morikazu Toda published the seminal papers
exhibiting soliton solutions to a chain of particles with nonlinear
interactions between nearest neighbors. In the decades that followed, Toda's
system of particles has been generalized in different directions, each with its
own analytic, geometric, and topological characteristics that sets it apart
from the others. These are known collectively as the Toda lattice. This survey
describes and compares several versions of the finite non-periodic Toda lattice
from the perspective of their geometry and topology.


title: Random projection trees for vector quantization

abstract:
  A simple and computationally efficient scheme for tree-structured vector
quantization is presented. Unlike previous methods, its quantization error
depends only on the intrinsic dimension of the data distribution, rather than
the apparent dimension of the space in which the data happen to lie.


title: Linear Time Algorithm for Weak Parity Games

abstract:
  We consider games played on graphs with the winning conditions for the
players specified as weak-parity conditions. In weak-parity conditions the
winner of a play is decided by looking into the set of states appearing in the
play, rather than the set of states appearing infinitely often in the play. A
naive analysis of the classical algorithm for weak-parity games yields a
quadratic time algorithm. We present a linear time algorithm for solving
weak-parity games.


title: Network rigidity and dynamics of oxides

abstract:
  If a hierarchy of interatomic interactions exists in a solid, low-frequency
modes can be found from viewing this solid as a mechanical network. In this
case, the low-frequency modes are determined by the network rigidity. We study
the low-frequency modes (rigid unit modes, or RUMs) in several important oxide
materials and discuss how the RUMs affect their properties. In SiO$_2$ glass,
the ability to support RUMs governs its relaxation in the wide range of
pressures and temperatures, giving rise to the non-trivial pressure window. It
also affects other properties, including crystallization, slow relaxation and
compressibility. At ambient pressure and low temperature, RUM flexibility is
related to the large-scale localized atomic motions. Whether these motions are
interpreted as independent two-level systems or collective density excitations,
the RUM flexibility determines whether and to what extent low-energy
excitations can exist in a given glass structure. Finally, we discuss the RUM
in, perhaps unexpectedly, cuprate superconductors, and its relevance for
superconductivity, including the d-wave symmetry of the order parameter and
other properties.


title: Impurities in triangular lattice spin 1/2 antiferromagnet

abstract:
  We study effects of nonmagnetic impurities in a spin-1/2 frustrated
triangular antiferromagnet with the aim of understanding the observed
broadening of $^{13}$C NMR lines in the organic spin liquid material
$\kappa$-(ET)$_2$Cu$_2$(CN)$_3$. For high temperatures down to $J/3$, we
calculate local susceptibility near a nonmagnetic impurity and near a grain
boundary for the nearest neighbor Heisenberg model in high temperature series
expansion. We find that the local susceptibility decays to the uniform one in
few lattice spacings, and for a low density of impurities we would not be able
to explain the line broadening present in the experiments already at elevated
temperatures. At low temperatures, we assume a gapless spin liquid with a Fermi
surface of spinons. We calculate the local susceptibility in the mean field and
also go beyond the mean field by Gutzwiller projection. The zero temperature
local susceptibility decays as a power law and oscillates at $2 k_F$. As in the
high temperature analysis we find that a low density of impurities is not able
to explain the observed broadening of the lines. We are thus led to conclude
that there is more disorder in the system. We find that a large density of
point-like disorder gives broadening that is consistent with the experiment
down to about 5K, but that below this temperature additional mechanism is
likely needed.


title:
Significant enhancement of hole mobility in [110] silicon nanowires
  compared to electrons and bulk silicon

abstract:
  Utilizing sp3d5s* tight-binding band structure and wave functions for
electrons and holes we show that acoustic phonon limited hole mobility in [110]
grown silicon nanowires (SiNWs) is greater than electron mobility. The room
temperature acoustically limited hole mobility for the SiNWs considered can be
as high as 2500 cm2/Vs, which is nearly three times larger than the bulk
acoustically limited silicon hole mobility. It is also shown that the electron
and hole mobility for [110] grown SiNWs exceed that of similar diameter [100]
SiNWs, with nearly two orders of magnitude difference for hole mobility. Since
small diameter SiNWs have been seen to grow primarily along [110] direction,
results strongly suggest that these SiNWs may be useful in future electronics.
Our results are also relevant to recent experiments measuring SiNW mobility.


title: Inference of ecological interaction networks

abstract:
  The inference of the interactions between organisms in an ecosystem from
observational data is an important problem in ecology. This paper presents a
mathematical inference method, originally developed for the inference of
biochemical networks in molecular biology, adapted for the inference of
networks of ecological interactions. The method is applied to a network of
invertebrate families (taxa) in a rice field.


title:
General segregation and chemical ordering in bimetallic nanoclusters
  through atomistic view points

abstract:
  We predict general trends for surface segregation in a binary metal cluster
based on the difference between the atomic properties of the constituent
elements. Considering the attractive and repulsive contributions of the
cohesive energy of an atom in a cluster, energetically most favorable sites for
a guest atom on a pure metal cluster is determined. It is predicted that for
adjacent elements in a row of the periodic table, the bimetallic system would
be more stable if the component with smallest valence electron density is
placed on the surface. On the contrary, for well separated components in the
periodic table, the bimetallic cluster would be more stable if the component
with the smallest core electron density is placed inside. Such chemical {\bf
ordering trends} in the lowest energy configurations of Pt-Au, Pt-Pd and Pt-Ni
binary alloy clusters are verified for their 561 atom systems through simulated
annealing process. It is predicted that the Ir, Rh, Ni, Pd atoms would tend to
be located inside the Ir-Pt, Rh-Pd, Ni-Cu and Pd-Ag bimetallic nanoclusters,
respectively.


title: Initial determination of the spins of the gluino and squarks at LHC

abstract:
  In principle particle spins can be measured from their production cross
sections once their mass is approximately known. The method works in practice
because spins are quantized and cross sections depend strongly on spins. It can
be used to determine, for example, the spin of the top quark. Direct
application of this method to supersymmetric theories will have to overcome the
challenge of measuring mass at the LHC, which could require high statistics. In
this article, we propose a method of measuring the spins of the colored
superpatners by combining rate information for several channels and a set of
kinematical variables, without directly measuring their masses. We argue that
such a method could lead to an early determination of the spin of gluino and
squarks. This method can be applied to the measurement of spin of other new
physics particles and more general scenarios.


title:
The Nekrasov-Okounkov hook length formula: refinement, elementary proof,
  extension and applications

abstract:
  The paper is devoted to the derivation of the expansion formula for the
powers of the Euler Product in terms of partition hook lengths, discovered by
Nekrasov and Okounkov in their study of the Seiberg-Witten Theory. We provide a
refinement based on a new property of t-cores, and give an elementary proof by
using the Macdonald identities. We also obtain an extension by adding two more
parameters, which appears to be a discrete interpolation between the Macdonald
identities and the generating function for t-cores. Several applications are
derived, including the "marked hook formula".


title:
$\delta$ meson effects on neutron stars in the modified quark-meson
  coupling model

abstract:
  The properties of neutron stars are investigated by including $\delta$ meson
field in the Lagrangian density of modified quark-meson coupling model. The
$\Sigma^-$ population with $\delta$ meson is larger than that without $\delta$
meson at the beginning, but it becomes smaller than that without $\delta$ meson
as the appearance of $\Xi^-$. The $\delta$ meson has opposite effects on
hadronic matter with or without hyperons: it softens the EOSes of hadronic
matter with hyperons, while it stiffens the EOSes of pure nucleonic matter.
Furthermore, the leptons and the hyperons have the similar influence on
$\delta$ meson effects. The $\delta$ meson increases the maximum masses of
neutron stars. The influence of $(\sigma^*,\phi)$ on the $\delta$ meson effects
are also investigated.


title: Einstein's E = mc^2 mistakes

abstract:
  Although Einstein's name is closely linked with the celebrated relation E =
mc2 between mass and energy, a critical examination of the more than half dozen
"proofs" of this relation that Einstein produced over a span of forty years
reveals that all these proofs suffer from mistakes. Einstein introduced
unjustified assumptions, committed fatal errors in logic, or adopted low-speed,
restrictive approximations. He never succeeded in producing a valid general
proof applicable to a realistic system with arbitrarily large internal and
external (that is, translational) speeds. The first such general proof was
produced by Max Laue in 1911 (for "closed" systems with a time-independent
energy-momentum tensor) and it was generalized by Felix Klein in 1918 (for
arbitrary time-dependent "closed" systems).


title: Approximation Algorithms for Shortest Descending Paths in Terrains

abstract:
  A path from s to t on a polyhedral terrain is descending if the height of a
point p never increases while we move p along the path from s to t. No
efficient algorithm is known to find a shortest descending path (SDP) from s to
t in a polyhedral terrain. We give two approximation algorithms (more
precisely, FPTASs) that solve the SDP problem on general terrains. Both
algorithms are simple, robust and easy to implement.


title:
QND measurements and state preparation in quantum gases by light
  detection

abstract:
  We consider light scattering from ultracold atoms trapped in an optical
lattice into a cavity. The measurement of photons leaking out the cavity
provides a quantum nondemolition (QND) access to various atomic variables.
Depending on the chosen geometry the time resolved light detection projects the
atomic quantum state to various atom-number squeezed and Schroedinger cat
states. Modifications of the atomic and light properties at a single quantum
trajectory are demonstrated. The quantum structure of final states can be
revealed by further observations of the same sample.

categories: quant-ph cond-mat.other physics.atom-ph physics.optics


title: Stability of thin-shell wormholes with spherical symmetry

abstract:
  In this article, the stability of a general class of spherically symmetric
thin-shell wormholes is studied under perturbations preserving the symmetry.
For this purpose, the equation of state at the throat is linearized around the
static solutions. The formalism presented here is applied to dilaton wormholes
and it is found that there is a smaller range of possible stable configurations
for them than in the case of Reissner-Nordstrom wormholes with the same charge.


title:
Adaptive estimation of a distribution function and its density in
  sup-norm loss by wavelet and spline projections

abstract:
  Given an i.i.d. sample from a distribution $F$ on $\mathbb{R}$ with uniformly
continuous density $p_0$, purely data-driven estimators are constructed that
efficiently estimate $F$ in sup-norm loss and simultaneously estimate $p_0$ at
the best possible rate of convergence over H\"older balls, also in sup-norm
loss. The estimators are obtained by applying a model selection procedure close
to Lepski's method with random thresholds to projections of the empirical
measure onto spaces spanned by wavelets or $B$-splines. The random thresholds
are based on suprema of Rademacher processes indexed by wavelet or spline
projection kernels. This requires Bernstein-type analogs of the inequalities in
Koltchinskii [Ann. Statist. 34 (2006) 2593-2656] for the deviation of suprema
of empirical processes from their Rademacher symmetrizations.


title: Coarse-graining of bubbling geometries and the fuzzball conjecture

abstract:
  In the LLM bubbling geometries, we compute the entropies of black holes and
estimate their "horizon" sizes from the fuzzball conjecture, based on
coarse-graining on the gravity side. The differences of black hole microstates
cannot be seen by classical observations. Conversely, by counting the possible
deformations of the geometry which are not classically detectable, we can
calculate the entropy. We carry out this method on the black holes of the LLM
bubbling geometries, such as the superstar, and obtain the same result as was
derived by coarse-graining directly on the CFT (fermion) side. Second, by
application of this method, we can estimate the "horizon" sizes of those black
holes, based on the fuzzball conjecture. The Bekenstein-Hawking entropy
computed from this "horizon" agrees with that microscopic entropy above. This
result supports the fuzzball conjecture.


title: Uniform limit theorems for wavelet density estimators

abstract:
  Let $p_n(y)=\sum_k\hat{\alpha}_k\phi(y-k)+\sum_{l=0}^{j_n-1}\sum_k\hat
{\beta}_{lk}2^{l/2}\psi(2^ly-k)$ be the linear wavelet density estimator, where
$\phi$, $\psi$ are a father and a mother wavelet (with compact support),
$\hat{\alpha}_k$, $\hat{\beta}_{lk}$ are the empirical wavelet coefficients
based on an i.i.d. sample of random variables distributed according to a
density $p_0$ on $\mathbb{R}$, and $j_n\in\mathbb{Z}$, $j_n\nearrow\infty$.
Several uniform limit theorems are proved: First, the almost sure rate of
convergence of $\sup_{y\in\mathbb{R}}|p_n(y)-Ep_n(y)|$ is obtained, and a law
of the logarithm for a suitably scaled version of this quantity is established.
This implies that $\sup_{y\in\mathbb{R}}|p_n(y)-p_0(y)|$ attains the optimal
almost sure rate of convergence for estimating $p_0$, if $j_n$ is suitably
chosen. Second, a uniform central limit theorem as well as strong invariance
principles for the distribution function of $p_n$, that is, for the stochastic
processes $\sqrt{n}(F_n
^W(s)-F(s))=\sqrt{n}\int_{-\infty}^s(p_n-p_0),s\in\mathbb{R}$, are proved; and
more generally, uniform central limit theorems for the processes
$\sqrt{n}\int(p_n-p_0)f$, $f\in\mathcal{F}$, for other Donsker classes
$\mathcal{F}$ of interest are considered. As a statistical application, it is
shown that essentially the same limit theorems can be obtained for the hard
thresholding wavelet estimator introduced by Donoho et al. [Ann. Statist. 24
(1996) 508--539].


title: Two classes of bipartite networks: nested biological and social systems

abstract:
  Bipartite graphs have received some attention in the study of social networks
and of biological mutualistic systems. A generalization of a previous model is
presented, that evolves the topology of the graph in order to optimally account
for a given Contact Preference Rule between the two guilds of the network. As a
result, social and biological graphs are classified as belonging to two clearly
different classes. Projected graphs, linking the agents of only one guild, are
obtained from the original bipartite graph. The corresponding evolution of its
statistical properties is also studied. An example of a biological mutualistic
network is analyzed in great detail, and it is found that the model provides a
very good quantitative fitting of its properties. The model also provides a
proper qualitative description of the statistical features observed in social
webs, suggesting the possible reasons underlying the difference in the
organization of these two kinds of bipartite networks.


title:
Solids and supersolids of three-body interacting polar molecules in an
  optical lattice

abstract:
  We study the physics of cold polar molecules loaded into an optical lattice
in the regime of strong three-body interactions, as put forward recently by
B\"uchler [Nature Phys. 3, 726 (2007)]. To this end quantum Monte Carlo
simulations, exact diagonalization and a semiclassical approach are used to
explore hardcore bosons on the two-dimensional square lattice which interact
solely by long ranged three-body terms. The resulting phase diagram shows a
sequence of solid and supersolid phases. Our findings are directly relevant for
future experimental implementations and open a new route towards the discovery
of a lattice supersolid phase in experiment.


title:
Calibrating Redshift Distributions Beyond Spectroscopic Limits with
  Cross-Correlations

abstract:
  We describe a new method for measuring the true redshift distribution of any
set of objects studied only photometrically. The angular cross-correlation
between objects in a photometric sample with objects in some spectroscopic
sample as a function of the spectroscopic z, in combination with standard
correlation measurements, provides sufficient information to reconstruct the
true redshift distribution of the photometric sample. This technique enables
the robust calibration of photometric redshifts even beyond spectroscopic
limits. The spectroscopic sample need not resemble the photometric one in
galaxy properties, but must overlap in sky coverage and redshift range. We test
this new technique with Monte Carlo simulations using realistic error
estimates. RMS errors in recovering both the mean and sigma of the true,
Gaussian redshift distribution of a single photometric redshift bin are
1.4x10^(-3) (sigma_z/0.1) (Sigma_p/10)^(-0.3) (dN_s/dz / 25,000)^(-0.5), where
sigma_z is the true sigma of the redshift distribution, Sigma_p is the surface
density of the photometric sample in galaxies/arcmin^2, and dN_s/dz is the
number of galaxies with a spectroscopic redshift per unit z. We test the impact
of redshift outliers and of a variety of sources of systematic error; none
dominate measurement uncertainties in reasonable scenarios. With this method,
the true redshift distributions of even arbitrarily faint photometric redshift
samples may be determined to the precision required by proposed dark energy
experiments (errors in mean and sigma below 3x10^(-3) at z~1) using expected
extensions of current spectroscopic samples.


title: Chiral Algebras of (0,2) Sigma Models: Beyond Perturbation Theory - II

abstract:
  We extend our analysis in [arXiv:0801.4782] and show that the chiral algebras
of (0,2) sigma models are totally trivialized by worldsheet instantons for all
complete flag manifolds of compact semisimple Lie groups. Consequently,
supersymmetry is spontaneously broken. Our results verify Stolz's idea that
there are no harmonic spinors on the loop spaces of these flag manifolds.
Moreover, they also imply that the kernels of certain twisted Dirac operators
on these spaces will be empty under a "quantum" deformation of their
geometries.


title: Cyclic cocycles on deformation quantizations and higher index theorems

abstract:
  We construct a nontrivial cyclic cocycle on the Weyl algebra of a symplectic
vector space. Using this cyclic cocycle we construct an explicit, local,
quasi-isomorphism from the complex of differential forms on a symplectic
manifold to the complex of cyclic cochains of any formal deformation
quantization thereof. We give a new proof of Nest-Tsygan's algebraic higher
index theorem by computing the pairing between such cyclic cocycles and the
$K$-theory of the formal deformation quantization. Furthermore, we extend this
approach to derive an algebraic higher index theorem on a symplectic orbifold.
As an application, we obtain the analytic higher index theorem of
Connes--Moscovici and its extension to orbifolds.


title: The Environments of High Redshift QSOs

abstract:
  We present a sample of $i_{775}$-dropout candidates identified in five Hubble
Advanced Camera for Surveys fields centered on Sloan Digital Sky Survey QSOs at
redshift $z\sim 6$. Our fields are as deep as the Great Observatory Origins
Deep Survey (GOODS) ACS images which are used as a reference field sample. We
find them to be overdense in two fields, underdense in two fields, and as dense
as the average density of GOODS in one field. The two excess fields show
significantly different color distributions from that of GOODS at the 99%
confidence level, strengthening the idea that the excess objects are indeed
associated with the QSO. The distribution of $i_{775}$-dropout counts in the
five fields is broader than that derived from GOODS at the 80% to 96%
confidence level, depending on which selection criteria were adopted to
identify $i_{775}$-dropouts; its width cannot be explained by cosmic variance
alone. Thus, QSOs seem to affect their environments in complex ways. We suggest
the picture where the highest redshift QSOs are located in very massive
overdensities and are therefore surrounded by an overdensity of lower mass
halos. Radiative feedback by the QSO can in some cases prevent halos from
becoming galaxies, thereby generating in extreme cases an underdensity of
galaxies. The presence of both enhancement and suppression is compatible with
the expected differences between lines of sight at the end of reionization as
the presence of residual diffuse neutral hydrogen would provide young galaxies
with shielding from the radiative effects of the QSO.


title: Quantum-critical relativistic magnetotransport in graphene

abstract:
  We study the thermal and electric transport of a fluid of interacting Dirac
fermions using a Boltzmann approach. We include Coulomb interactions, a dilute
density of charged impurities and the presence of a magnetic field to describe
both the static and the low frequency response as a function of temperature T
and chemical potential mu. In the quantum-critical regime mu << T we find
pronounced deviations from Fermi liquid behavior, such as a collective
cyclotron resonance with an intrinsic, collision-broadened width, and
significant enhancements of the Mott and Wiedemann-Franz ratio. Some of these
results have been anticipated by a relativistic hydrodynamic theory, whose
precise range of validity and failure at large fields and frequencies we
determine. The Boltzmann approach allows us to go beyond the hydrodynamic
regime, and to quantitatively describe the deviations from
magnetohydrodynamics, the crossover to disorder dominated Fermi liquid behavior
at large doping and low temperatures, as well as the crossover to the ballistic
regime at high fields. Finally, we obtain the full frequency and doping
dependence of the single universal conductivity sigma_Q which parametrizes the
hydrodynamic response.


title: A New Definition of the Steenrod Operations in Algebraic Geometry

abstract:
  The Steenrod operations (mod p) in Chow theory are defined for any prime p
for a quasi-projective scheme, without appealing to the results of any domain
but Milnor's K-theory. The new definition also gives a direct formula that
depends only on the scheme itself. Additionally, basic properties of the
operations are proved from the new definition. The idea is based on a
construction of M. Rost.


title: Theory of non-equilibrium thermoelectric effects in nanoscale junctions

abstract:
  Despite its intrinsic non-equilibrium origin, thermoelectricity in nanoscale
systems is usually described within a static scattering approach which
disregards the dynamical interaction with the thermal baths that maintain
energy flow. Using the theory of open quantum systems we show instead that
unexpected properties, such as a resonant structure and large sign sensitivity,
emerge if the non-equilibrium nature of this problem is considered. Our
approach also allows us to define and study a local temperature, which shows
hot spots and oscillations along the system according to the coupling of the
latter to the electrodes. This demonstrates that Fourier's law -- a paradigm of
statistical mechanics -- is violated at the nanoscale.


title: Realization of Coherent Optically Dense Media via Buffer-Gas Cooling

abstract:
  We demonstrate that buffer-gas cooling combined with laser ablation can be
used to create coherent optical media with high optical depth and low Doppler
broadening that offers metastable states with low collisional and motional
decoherence. Demonstration of this generic technique opens pathways to coherent
optics with a large variety of atoms and molecules. We use helium buffer gas to
cool 87Rb atoms to below 7 K and slow atom diffusion to the walls.
Electromagnetically induced transparency (EIT) in this medium allows for 50%
transmission in a medium with initial OD >70 and for slow pulse propagation
with large delay-bandwidth products. In the high-OD regime, we observe
high-contrast spectrum oscillations due to efficient four-wave mixing.


title:
Charge, geometry, and effective mass in the Kerr-Newman solution to the
  Einstein field equations

abstract:
  It has been shown that for the Reissner-Nordstrom solution to the vacuum
Einstein field equations charge, like mass, has a unique space-time signature
[Found. Phys. 38, 293-300 (2008)]. The presence of charge results in a negative
curvature. This work, which includes a discussion of effective mass, is
extended here to the Kerr-Newman solution.


title:
An Improved Real--Space Genetic Algorithm for Crystal Structure and
  Polymorph Prediction

abstract:
  Existing Genetic Algorithms for crystal structure and polymorph prediction
can suffer from stagnation during evolution, with a consequent loss of
efficiency and accuracy. An improved Genetic Algorithm (GA) is introduced
herein which penalizes similar structures and so enhances structural diversity
in the population at each generation. This is shown to improve the quality of
results found for the theoretical prediction of simple model crystal
structures. In particular, this method is demonstrated to find three new
zero--temperature phases of the Dzugutov potential that have not been
previously reported.


title:
Leading SU(3)-breaking corrections to the baryon magnetic moments in
  Chiral Perturbation Theory

abstract:
  We calculate the baryon magnetic moments using covariant Chiral Perturbation
Theory ($\chi$PT) within the Extended-on-mass-shell (EOMS) renormalization
scheme. By fitting the two available low-energy constants (LECs), we improve
the Coleman-Glashow description of the data when we include the leading SU(3)
breaking effects coming from the lowest-order loops. This success is in
dramatic contrast with previous attempts at the same order using Heavy Baryon
(HB) $\chi$PT and covariant Infrared (IR) $\chi$PT. We also analyze the source
of this improvement with particular attention on the comparison between the
covariant results.


title:
Effects of gravitational-wave recoil on the dynamics and growth of
  supermassive black holes

abstract:
  Simulations of binary black hole mergers indicate that asymmetrical
gravitational wave (GW) emission can cause black holes to recoil at speeds up
to thousands of km/s. These GW recoil events can dramatically affect the
coevolution of recoiling supermassive black holes (SMBHs) and their host
galaxies. However, theoretical studies of SMBH-galaxy evolution almost always
assume a stationary central black hole. In light of the numerical results on GW
recoil velocities, we relax that assumption here and consider the consequences
of recoil for SMBH evolution. We follow the trajectories of SMBHs ejected in a
smooth background potential that includes both a stellar bulge and a
multi-component gaseous disk. In addition, we calculate the accretion rate onto
the SMBH as a function of time using a hybrid prescription of viscous
(alpha-disk) and Bondi accretion. We find that recoil kicks between 100 km/s
and the escape speed cause SMBHs to wander through the galaxy and halo for
about 1 Myr - 1 Gyr before settling back to the galactic center. However, the
mass accreted during this time is roughly constant at about 10% of the initial
mass, independent of the recoil velocity. This indicates that while large
recoils may disrupt active galactic nuclei feedback processes, recoil itself is
an effective means of regulating SMBH growth. Recoiling SMBHs may be observable
as spatially or kinematically offset quasars, but finding such systems could be
challenging, because the largest offsets correspond to the shortest quasar
lifetimes.


title:
Evidence of Turbulence-like Universality on the Formation of
  Galaxy-sized Dark Matter Haloes

abstract:
  Although the theoretical understanding of the nonlinear gravitational
clustering has greatly advanced in the last decades, in particular by the
outstanding improvement on numerical N-body simulations, the physics behind
this process is not fully elucidated. The main goal of this work is the study
of the possibility of a turbulent-like physical process in the formation of
structures, galaxies and clusters of galaxies, by the action of gravity alone.
We use simulation data from the Virgo Consortium, in ten redshift snapshots
(from 0 to 10). From this we identify galaxy-sized and cluster-sized dark
matter haloes, by using a FoF algorithm and applying a boundedness criteria,
and study the gravitational potential energy spectra. We find that the
galaxy-sized haloes energy spectrum follows closely a Kolmogorov's power law,
similar to the behaviour of dynamically turbulent processes in fluids. This
means that the gravitational clustering of dark matter may admit a
turbulent-like representation.


title:
On existence and asymptotic behaviour of solutions of a fractional
  integral equation with linear modification of the argument

abstract:
  We study the solvability of a quadratic integral equation of fractional order
with linear modification of the argument. This equation is considered in the
Banach space of real functions defined, bounded and continuous on an unbounded
interval. Moreover, we will obtain some asymptotic characterization of
solutions.


title: Five Dimensional bigravity. New topological description of the Universe

abstract:
  We extend the bimetric description of the Universe to a five-dimensional
framework. Starting from Souriau's work (1964) we use two Robertson-Walker
metrics with an extra term corresponding to the additional Kaluza fifth
dimension. This first order model is limited to zero electric charge and
electromagnetic energy densities. Assuming the massive particles, with positive
or negative mass and energies owing finite lifetimes, it restores the O(3)
symmetry and makes the generalized gauge process to restart. As a consequence
the speed of light tends to zero. We assume the Universe to be closed over all
its dimensions. Then, following an idea introduced in 1994 we describe the
Universe as the two folds cover of a projective space. The arrow of time, mass
and energy inversions arise as consequences of this geometrical hypothesis and
fits the bimetric model. We choose to eliminate the "initial singularity",
replaced by a boundary space, which is found to be euclidean.


title: Standard isotrivial fibrations with p_g=q=1. II

abstract:
  A smooth, projective surface $S$ is called a $\emph{standard isotrivial
fibration}$ if there exists a finite group $G$ which acts faithfully on two
smooth projective curves $C$ and $F$ so that $S$ is isomorphic to the minimal
desingularization of $T:=(C \times F)/G$. Standard isotrivial fibrations of
general type with $p_g=q=1$ have been classified in \cite{Pol07} under the
assumption that $T$ has only Rational Double Points as singularities. In the
present paper we extend this result, classifying all cases where $S$ is a
minimal model. As a by-product, we provide the first examples of minimal
surfaces of general type with $p_g=q=1$, $K_S^2=5$ and Albanese fibration of
genus 3. Finally, we show with explicit examples that the case where $S$ is not
minimal actually occurs.


title:
High-Dimensional Menger-Type Curvatures - Part I: Geometric Multipoles
  and Multiscale Inequalities

abstract:
  We define a discrete Menger-type curvature of d+2 points in a real separable
Hilbert space H by an appropriate scaling of the squared volume of the
corresponding (d+1)-simplex. We then form a continuous curvature of an Ahlfors
d-regular measure on H by integrating the discrete curvature according to the
product measure. The aim of this work, continued in a subsequent paper, is to
estimate multiscale least squares approximations of such measures by the
Menger-type curvature. More formally, we show that the continuous d-dimensional
Menger-type curvature is comparable to the ``Jones-type flatness''. The latter
quantity adds up scaled errors of approximations of a measure by d-planes at
different scales and locations, and is commonly used to characterize uniform
rectifiability. We thus obtain a characterization of uniform rectifiability by
using the Menger-type curvature. In the current paper (part I) we control the
continuous Menger-type curvature of an Ahlfors d-regular measure by its
Jones-type flatness.


title:
Optimal Coaddition of Imaging Data for Rapidly Fading Gamma-Ray Burst
  Afterglows

abstract:
  We present a technique for optimal coaddition of image data for rapidly
varying sources, with specific application to gamma-ray burst (GRB) afterglows.
Unweighted coaddition of rapidly fading afterglow lightcurve data becomes
counterproductive relatively quickly. It is better to stop coaddition of the
data once noise dominates late exposures. A better alternative is to optimally
weight each exposure to maximize the signal-to-noise ratio (S/N) of the final
coadded image data. By using information about GRB lightcurves and image noise
characteristics, optimal image coaddition increases the probability of
afterglow detection and places the most stringent upper limits on
non-detections. For a temporal power law flux decay typical of GRB afterglows,
optimal coaddition has the greatest potential to improve the S/N of afterglow
imaging data (relative to unweighted coaddition), when the decay rate is high,
the source count rate is low, and the background rate is high. The optimal
coaddition technique is demonstrated with applications to Swift
Ultraviolet/Optical Telescope (UVOT) data of several GRBs, with and without
detected afterglows.


title: The Dynamics Theorem for CMC surfaces in R^3

abstract:
  In this paper, we study the space of translational limits T(M) of a surface M
properly embedded in R^3 with nonzero constant mean curvature and bounded
second fundamental form. There is a natural map T which assigns to any surface
M' in T(M), the set T(M') in T(M). Among various dynamics type results we prove
that surfaces in minimal T-invariant sets of T(M) are chord-arc. We also show
that if M has an infinite number of ends, then there exists a nonempty minimal
T-invariant set in T(M) consisting entirely of surfaces with planes of
Alexandrov symmetry. Finally, when M has a plane of Alexandrov symmetry, we
prove the following characterization theorem: M has finite topology if and only
if M has a finite number of ends greater than one.


title:
Mergers of nonspinning black-hole binaries: Gravitational radiation
  characteristics

abstract:
  We present a detailed descriptive analysis of the gravitational radiation
from black-hole binary mergers of nonspinning black holes, based on numerical
simulations of systems varying from equal-mass to a 6:1 mass ratio. Our primary
goal is to present relatively complete information about the waveforms,
including all the leading multipolar components, to interested researchers. In
our analysis, we pursue the simplest physical description of the dominant
features in the radiation, providing an interpretation of the waveforms in
terms of an {\em implicit rotating source}. This interpretation applies
uniformly to the full wave train, from inspiral through ringdown. We emphasize
strong relationships among the $\ell=m$ modes that persist through the full
wave train. Exploring the structure of the waveforms in more detail, we conduct
detailed analytic fitting of the late-time frequency evolution, identifying a
key quantitative feature shared by the $\ell=m$ modes among all mass ratios. We
identify relationships, with a simple interpretation in terms of the implicit
rotating source, among the evolution of frequency and amplitude, which hold for
the late-time radiation. These detailed relationships provide sufficient
information about the late-time radiation to yield a predictive model for the
late-time waveforms, an alternative to the common practice of modeling by a sum
of quasinormal mode overtones. We demonstrate an application of this in a new
effective-one-body-based analytic waveform model.


title: VSOP and stellar sources - the case of LS I +61 303

abstract:
  Space-VLBI observations of stellar sources represent a challenge since there
are few sources with sufficiently high brightness temperature for detection on
space-ground baselines. X-ray binaries (XRB) are among the few types of stellar
radio sources that can be detected. Observations of the unusual X-ray and
gamma-ray binary system LS I 61 303 obtained with the HALCA satellite and a
20-element ground array are described. The data in this 48-hour experiment
represent some of the best quality VLBI observations of LS I 61 303. No fringes
were detected on HALCA baselines. 10-minute snapshot images were produced from
the global ground array data and reveal an expansion velocity of 800 km/s. Some
of these image data reveal hints of more extended emission but high-SNR closure
phase data do not support relativistic outflow in the plane-of-the-sky in LSI
61 303. The largest closure phase rates are consistent with an outflow of ~1000
km/s as deduced from the image data. The closure phases also show no evidence
of structure variation on size scales greater than ~10 mas. A number of issues
related to VSOP2 observations of stellar radio sources are raised.


title:
On d-dimensional d-Semimetrics and Simplex-Type Inequalities for
  High-Dimensional Sine Functions

abstract:
  We show that high-dimensional analogues of the sine function (more precisely,
the d-dimensional polar sine and the d-th root of the d-dimensional hypersine)
satisfy a simplex-type inequality in a real pre-Hilbert space H. Adopting the
language of Deza and Rosenberg, we say that these d-dimensional sine functions
are d-semimetrics. We also establish geometric identities for both the
d-dimensional polar sine and the d-dimensional hypersine. We then show that
when d=1 the underlying functional equation of the corresponding identity
characterizes a generalized sine function. Finally, we show that the
d-dimensional polar sine satisfies a relaxed simplex inequality of two
controlling terms "with high probability".


title: Cavity-Assisted Back Action Cooling of Mechanical Resonators

abstract:
  We analyze the quantum regime of the dynamical backaction cooling of a
mechanical resonator assisted by a driven harmonic oscillator (cavity). Our
treatment applies to both optomechanical and electromechanical realizations and
includes the effect of thermal noise in the driven oscillator. In the
perturbative case, we derive the corresponding motional master equation using
the Nakajima-Zwanzig formalism and calculate the corresponding output spectrum
for the optomechanical case. Then we analyze the strong optomechanical coupling
regime in the limit of small cavity linewidth. Finally we consider the steady
state covariance matrix of the two coupled oscillators for arbitrary input
power and obtain an analytical expression for the final mechanical occupancy.
This is used to optimize the drive's detuning and input power for an
experimentally relevant range of parameters that includes the "ground state
cooling" regime.


title: The decoherence of coupled spin qubits system

abstract:
  In this report, we examine the decoherence of a spin qubits system coupled to
counted spin chain with a $1/r^2$ interaction by using influence functional. We
also examine the time evolution of density matrix numerically when environment
is Gaussian noise.


title: Dipolar Ordering and Quantum Dynamics of Domain Walls in Mn-12 Acetate

abstract:
  We find that dipolar interactions favor ferromagnetic ordering of elongated
crystals of Mn12 Acetate below 0.8 K. Ordered crystals must possess domain
walls. Motion of the wall corresponds to a moving front of Landau-Zener
transitions between quantum spin levels. Structure and mobility of the wall are
computed. The effect is robust with respect to inhomogeneous broadening and
decoherence.


title: Degree-distribution stability of scale-free networks

abstract:
  Based on the concept and techniques of first-passage probability in Markov
chain theory, this letter provides a rigorous proof for the existence of the
steady-state degree distribution of the scale-free network generated by the
Barabasi-Albert (BA) model, and mathematically re-derives the exact analytic
formulas of the distribution. The approach developed here is quite general,
applicable to many other scale-free types of complex networks.


title:
Structural and phase properties of tetracosane (C24H50) monolayers
  adsorbed on graphite. Explicit Hydrogen Molecular Dynamics study

abstract:
  We discuss Molecular Dynamics (MD) computer simulations of tetracosane
(C24H50) monolayer physisorbed onto a graphite surface. The alkane molecules
are simulated with explicit hydrogens, and the graphite substrate is
represented as an all-atom struc-ture having six graphene layers. The
tetracosane dynamics modeled in the fully ato-mistic manner agree well with
experiment. The low-temperature ordered solid orga-nizes in rectangular
centered structure, incommensurate with underlying graphite. Above T = 200 K,
as the molecules start to lose their translational and orientational order via
gauche defects formation, a weak smectic mesophase (observed experimentally but
never reproduced in United Atom (UA) simulations) appears. The phase behavior
of the adsorbed layer is critically sensitive to the way the electrostatic
interactions is included in the model. If the electrostatic charges are set to
zero (as it is in UA force field), the melting temperature increases by ~70 K
with respect to the experimental value. When the non-bonded 1-4 interaction is
not scaled, the melting temperature decreases by ~90 K. If the scaling factor
is set to 0.5, the melting occurs at T = 350 K, in very good agreement with
experimental data. PACS number: 82.45.Mp, 64.70.dj


title: On the magnetic structure of the solar transition region

abstract:
  We examine the hypothesis that ``cool loops'' dominate emission from solar
transition region plasma below temperatures of $2\times10^5$K. We compare
published VAULT images of H L$\alpha$, a lower transition region line, with
near-contemporaneous magnetograms from Kitt Peak, obtained during the second
flight (VAULT-2) on 14 June 2002. The measured surface fields and potential
extrapolations suggest that there are too few short loops, and that L$\alpha$
emission is associated with the base regions of longer, coronal loops. VAULT-2
data of network boundaries have an asymmetry on scales larger than
supergranules, also indicating an association with long loops. We complement
the Kitt Peak data with very sensitive vector polarimetric data from the
Spectro-Polarimeter on board Hinode, to determine the influence of very small
magnetic concentrations on our analysis. From these data two classes of
behavior are found: within the cores of strong magnetic flux concentrations ($>
5\times10^{18}$ Mx) associated with active network and plage, small-scale mixed
fields are absent and any short loops can connect just the peripheries of the
flux to cell interiors. Core fields return to the surface via longer, most
likely coronal, loops. In weaker concentrations, short loops can connect
between concentrations and produce mixed fields within network boundaries as
suggested by Dowdy and colleagues. The VAULT-2 data which we examined are
associated with strong concentrations. We conclude that the cool loop model
applies only to a small fraction of the VAULT-2 emission, but we cannot
discount a significant role for cool loops in quieter regions. We suggest a
physical picture for how network L$\alpha$ emission may occur through the
cross-field diffusion of neutral atoms from chromospheric into coronal plasma.


title: On the Spectrum of Large Random Hermitian Finite-Band Matrices

abstract:
  The open problem of calculating the limiting spectrum (or its Shannon
transform) of increasingly large random Hermitian finite-band matrices is
described. In general, these matrices include a finite number of non-zero
diagonals around their main diagonal regardless of their size. Two different
communication setups which may be modeled using such matrices are presented: a
simple cellular uplink channel, and a time varying inter-symbol interference
channel. Selected recent information-theoretic works dealing directly with such
channels are reviewed. Finally, several characteristics of the still unknown
limiting spectrum of such matrices are listed, and some reflections are touched
upon.


title: Resonant Tunneling through double-bended Graphene Nanoribbons

abstract:
  We investigate theoretically resonant tunneling through double-bended
graphene nanoribbon structures, i.e., armchair-edged graphene nanoribbons
(AGNRs) in between two semi-infinite zigzag graphene nanoribbon (ZGNR) leads.
Our numerical results demonstrate that the resonant tunneling can be tuned
dramatically by the Fermi energy and the length and/or widths of the AGNR for
both the metallic and semiconductor-like AGNRs. The structure can also be use
to control the valley polarization of the tunneling currents and could be
useful for potential application in valleytronics devices.


title: Quivers, long exact sequences and Horn type inequalities II

abstract:
  We study the set of all m-tuples $(\lambda(1),...,\lambda(m))$ of possible
types of finite abelian p-groups $M_{\lambda(1)}, ..., M_{\lambda(m)}$ for
which there exists a long exact sequence $M_{\lambda(1)} \to ... \to
M_{\lambda(m)}$. When m=3, we recover Fulton's results on the possible
eigenvalues of majorized Hermitian matrices.


title: Notes on GIT-fans for quivers

abstract:
  These are notes on the construction of the GIT-fans for quivers without
oriented cycles. We follow closely the steps outlined by N. Ressayre in "The
GIT-Equivalence for G-Line Bundles" (Geometriae Dedicata, Volume 81, Numbers
1-3, 2000). A simple construction of the GIT-fan for normal, affine G-varities
has been recently given by Ivan V. Arzhantsev and Juergen Hausen in "Geometric
Invariant Theory via Cox Rings"


title: Linking diagrams for free

abstract:
  Linking diagrams with path composition are ubiquitous, for example:
Temperley-Lieb and Brauer monoids, Kelly-Laplaza graphs for compact closed
categories, and Girard's multiplicative proof nets. We construct the category
Link=Span(iRel), where iRel is the category of injective relations (reversed
partial functions) and show that the aforementioned linkings, as well as
Jones-Martin partition monoids, reside inside Link. Path composition, including
collection of loops, is by pullback. Link contains the free compact closed
category on a self-dual object (hence also the looped Brauer and Temperly-Lieb
monoids), and generalises partition monoids with partiality (vertices in no
partition) and empty- and infinite partitions. Thus we obtain conventional
linking/partition diagrams and their composition "for free", from iRel.


title: How Many Users should be Turned On in a Multi-Antenna Broadcast Channel?

abstract:
  This paper considers broadcast channels with L antennas at the base station
and m single-antenna users, where L and m are typically of the same order. We
assume that only partial channel state information is available at the base
station through a finite rate feedback. Our key observation is that the optimal
number of on-users (users turned on), say s, is a function of signal-to-noise
ratio (SNR) and feedback rate. In support of this, an asymptotic analysis is
employed where L, m and the feedback rate approach infinity linearly. We derive
the asymptotic optimal feedback strategy as well as a realistic criterion to
decide which users should be turned on. The corresponding asymptotic throughput
per antenna, which we define as the spatial efficiency, turns out to be a
function of the number of on-users s, and therefore s must be chosen
appropriately. Based on the asymptotics, a scheme is developed for systems with
finite many antennas and users. Compared with other studies in which s is
presumed constant, our scheme achieves a significant gain. Furthermore, our
analysis and scheme are valid for heterogeneous systems where different users
may have different path loss coefficients and feedback rates.


title:
The Computational Status of Physics: A Computable Formulation of Quantum
  Theory

abstract:
  According to the Church-Turing Thesis (CTT), effective formal behaviours can
be simulated by Turing machines; this has naturally led to speculation that
physical systems can also be simulated computationally. But is this wider claim
true, or do behaviours exist which are strictly hypercomputational? Several
idealised computational models are known which suggest the possibility of
hypercomputation, some Newtonian, some based on cosmology, some on quantum
theory. While these models' physicality is debatable, they nonetheless throw
into question the validity of extending CTT to include all physical systems. We
consider the physicality of hypercomputational behaviour from first principles,
by showing that quantum theory can be reformulated in a way that explains why
physical behaviours can be regarded as 'computing something' in the standard
computational state-machine sense. While this does not rule out the physicality
of hypercomputation, it strongly limits the forms it can take. Our model also
has physical consequences; in particular, the continuity of motion and arrow of
time become theorems within the basic model.


title: V4633 Sgr - a probable second asynchronous polar classical nova

abstract:
  Photometric observations of V4633 Sgr (Nova Sagittarii 1998) during 1998-2005
reveal the presence of a stable photometric periodicity at P1=180.8 min which
is probably the orbital period of the underlying binary system. A second period
was present in the light curve of the object for six years. Shortly after the
nova eruption it was measured as P2=185.6 min. It has decreased monotonically
in the following few years reaching the value P2=183.9 min in 2003. In 2004 it
was no longer detectable. We suggest that the second periodicity is the spin of
the magnetic white dwarf of this system that rotates nearly synchronously with
the orbital revolution. According to our interpretation, the post-eruption
evolution of Nova V4633 Sgr follows a track similar to the one taken by V1500
Cyg (Nova Cygni 1975) after that nova eruption, on a somewhat longer time
scale. The asynchronism is probably the result of the nova outburst that lead
to a considerable expansion of the white dwarf's photosphere. The increase in
the moment of inertia of the star was associated with a corresponding decrease
in its spin rate. Our observations have followed the spinning up of the white
dwarf resulting from the contraction of its outer envelope as the star is
slowly retuning to its pre-outburst state. It is thus the second known
asynchronous polar classical nova.


title: Geometric Characterization of Solitons

abstract:
  I show that $H^1$ solutions of the nonlinear Schroedinger equation which are
incoming converge to a soliton, in the radial case.


title:
Magnetic and Electric Dipole Constraints on Extra Dimensions and
  Magnetic Fluxes

abstract:
  The propagation of charged particles and gauge fields in a compact extra
dimension contributes to $g-2$ of the charged particles. In addition, a
magnetic flux threading this extra dimension generates an electric dipole
moment for these particles. We present constraints on the compactification size
and on the possible magnetic flux imposed by the comparison of data and theory
of the magnetic moment of the muon and from limits on the electric dipole
moments of the muon, neutron and electron.


title: Braid ordering and the geometry of closed braid

abstract:
  The relationships between braid ordering and the geometry of its closure is
studied. We prove that if an essential closed surface $F$ in the complements of
closed braid has relatively small genus with respect to the Dehornoy floor of
the braid, $F$ is circular-foliated in a sense of Birman-Menasco's Braid
foliation theory. As an application of the result, we prove that if Dehornoy
floor of braids are larger than three, Nielsen-Thurston classification of
braids and the geometry of their closure's complements are in one-to-one
correspondence. Using this result, we construct infinitely many hyperbolic
knots explicitly from pseudo-Anosov element of mapping class groups.


title: No detectable radio emission from the magnetar-like pulsar in Kes 75

abstract:
  The rotation-powered pulsar PSR J1846-0258 in the supernova remnant Kes 75
was recently shown to have exhibited magnetar-like X-ray bursts in mid-2006.
Radio emission has not yet been observed from this source, but other
magnetar-like sources have exhibited transient radio emission following X-ray
bursts. We report on a deep 1.9 GHz radio observation of PSR J1846-0258 with
the 100-m Green Bank Telescope in late 2007 designed to search for radio
pulsations or bursts from this target. We have also analyzed three shorter
serendipitous 1.4 GHz radio observations of the source taken with the 64-m
Parkes telescope during the 2006 bursting period. We detected no radio emission
from PSR J1846-0258 in either the Green Bank or Parkes datasets. We place an
upper limit of 4.9 \mu Jy on coherent pulsed emission from PSR J1846-0258 based
on the 2007 November 2 observation, and an upper limit of 27 \mu Jy around the
time of the X-ray bursts. Serendipitously, we observed radio pulses from the
nearby RRAT J1846-02, and place a 3\sigma confidence level upper limit on its
period derivative of 1.7 * 10^{-13}, implying its surface dipole magnetic field
is less than 2.6 * 10^{13} G.


title: A sequential algorithm for fast clique percolation

abstract:
  In complex network research clique percolation, introduced by Palla et al.,
is a deterministic community detection method, which allows for overlapping
communities and is purely based on local topological properties of a network.
Here we present a sequential clique percolation algorithm (SCP) to do fast
community detection in weighted and unweighted networks, for cliques of a
chosen size. This method is based on sequentially inserting the constituent
links to the network and simultaneously keeping track of the emerging community
structure. Unlike existing algorithms, the SCP method allows for detecting
k-clique communities at multiple weight thresholds in a single run, and can
simultaneously produce a dendrogram representation of hierarchical community
structure. In sparse weighted networks, the SCP algorithm can also be used for
implementing the weighted clique percolation method recently introduced by
Farkas et al. The computational time of the SCP algorithm scales linearly with
the number of k-cliques in the network. As an example, the method is applied to
a product association network, revealing its nested community structure.


title: FFLO Superconductivity near the Antiferromagnetic Quantum Critical Point

abstract:
  The Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) state near the antiferromagnetic
quantum critical point (AFQCP) is investigated by analyzing the two dimensional
Hubbard model on the basis of the fluctuation exchange (FLEX) approximation.
The phase diagram against the magnetic field and temperature is compared with
that obtained in the BCS theory.
  We discuss the influences of the antiferromagnetic spin fluctuation through
the quasiparticle scattering, retardation effect, parity mixing and internal
magnetic field. It is shown that the FFLO state is stable in the vicinity of
AFQCP even though the quasiparticle scattering due to the spin fluctuation is
destructive to the FFLO state. The large positive slope dH_{FFLO}/dT and the
convex curvature (d^{2}H_{FFLO}/dT^{2} > 0) are obtained, where H_{FFLO} is the
critical magnetic field for the second order phase transition from the uniform
BCS state to the FFLO state. These results are consistent with the experimental
results in CeCoIn_5. The possible magnetic transition in the FFLO state is
examined.


title: Symmetries of Higher Dimensional Black Holes

abstract:
  We prove that if a stationary, real analytic, asymptotically flat vacuum
black hole spacetime of dimension $n\geq 4$ contains a non-degenerate horizon
with compact cross sections that are transverse to the stationarity generating
Killing vector field then, for each connected component of the black hole's
horizon, there is a Killing field which is tangent to the generators of the
horizon. For the case of rotating black holes, the stationarity generating
Killing field is not tangent to the horizon generators and therefore the
isometry group of the spacetime is at least two dimensional. Our proof relies
on significant extensions of our earlier work on the symmetries of spacetimes
containing a compact Cauchy horizon, allowing now for non closed generators of
the horizon.


title: The Molecular Ridge Close to 30 Doradus in the Large Magellanic Cloud

abstract:
  With the ATNF Mopra telescope we are performing a survey in the 12CO(1-0)
line to map the molecular gas in the Large Magellanic Cloud (LMC). For some
regions we also obtained interferometric maps of the high density gas tracers
HCO+ and HCN with the Australia Telescope Compact Array (ATCA). Here we discuss
the properties of the elongated molecular complex that stretches about 2 kpc
southward from 30 Doradus. Our data suggests that the complex, which we refer
to as the ``molecular ridge,'' is not a coherent feature but consists of many
smaller clumps that share the same formation history. Likely molecular cloud
formation triggers are shocks and shearing forces that are present in the
surrounding south-eastern HI overdensity region, a region influenced by strong
ram pressure and tidal forces. The molecular ridge is at the western edge of
the the overdensity region where a bifurcated velocity structure transitions
into a single disk velocity component. We find that the 12CO(1-0) and HI
emission peaks in the molecular ridge are typically near each other but never
coincide. A likely explanation is the conversion of warmer, low-opacity HI to
colder, high-opacity HI from which H2 subsequently forms. On smaller scales, we
find that very dense molecular gas, as traced by interferometric HCO+ and HCN
maps, is associated with star formation along shocked filaments and with rims
of expanding shell-like structures, both created by feedback from massive
stars.


title: Cosmological simulations of structure formation and the Vlasov equation

abstract:
  In cosmology numerical simulations of structure formation are now of central
importance, as they are the sole instrument for providing detailed predictions
of current cosmological models for a whole class of important constraining
observations. These simulations are essentially molecular dynamics simulations
of N (>> 1), now up to of order several billion) particles interacting through
their self-gravity. While their aim is to produce the Vlasov limit, which
describes the underlying (``cold dark matter'') models, the degree to which
they actually do produce this limit is currently understood, at best, only very
qualitatively, and there is an acknowledged need for ``a theory of discreteness
errors''. In this talk I will describe, for non-cosmologists, both the
simulations and the underlying theoretical models, and will then focus on the
issue of discreteness, describing some recent progress in addressing this
question quantitatively.


title:
Theoretical Formulation of the Phobos, moon of Mars, rate of altitudinal
  loss

abstract:
  Phobos is a moon of mars below the synchronous orbit. Because of tidal
interaction it is losing its altitude and is launched on a shrinking spiral
path of total destruction. Based on planetary-satellite dynamics its rate of
loss of altitude is calculated to be twenty meters per century and its doomsday
is predicted to be at eleven mega years from now.


title: On the Ramsey numbers for paths and generalized Jahangir graphs

abstract:
  For given graphs $G$ and $H,$ the \emph{Ramsey number} $R(G,H)$ is the least
natural number $n$ such that for every graph $F$ of order $n$ the following
condition holds: either $F$ contains $G$ or the complement of $F$ contains $H.$
In this paper, we determine the Ramsey number of paths versus generalized
Jahangir graphs. We also derive the Ramsey number $R(tP_n,H)$, where $H$ is a
generalized Jahangir graph $J_{s,m}$ where $s\geq2$ is even, $m\geq3$ and
$t\geq1$ is any integer.


title:
Teleportation in the presence of common bath decoherence at the
  transmitting station

abstract:
  We investigate the effect of common bath decoherence on the qubits of Alice
in the usual teleportation protocol. The system bath interaction is studied
under the central spin model, where the qubits are coupled to the bath spins
through isotropic Heisenberg interaction. We have given a more generalized
representation of the protocol in terms of density matrices and calculated the
average fidelity of the teleported state for different Bell state measurements
performed by Alice. The common bath interaction differentiates the outcome of
various Bell state measurements made by Alice. There will be a high fidelity
teleportation for a singlet measurement made by Alice when both the qubits of
Alice interact either ferromagnetically or antiferromagnetically with bath. In
contrast if one of the Alice's qubits interact ferromagnetically and the other
anti-ferromagnetically then measurement of Bell states belonging to the triplet
sector will give better fidelity. We have also evaluated the average fidelity
when Alice prefers non-maximally entangled states as her basis for measurement.


title: Model Checking One-clock Priced Timed Automata

abstract:
  We consider the model of priced (a.k.a. weighted) timed automata, an
extension of timed automata with cost information on both locations and
transitions, and we study various model-checking problems for that model based
on extensions of classical temporal logics with cost constraints on modalities.
We prove that, under the assumption that the model has only one clock,
model-checking this class of models against the logic WCTL, CTL with
cost-constrained modalities, is PSPACE-complete (while it has been shown
undecidable as soon as the model has three clocks). We also prove that
model-checking WMTL, LTL with cost-constrained modalities, is decidable only if
there is a single clock in the model and a single stopwatch cost variable
(i.e., whose slopes lie in {0,1}).


title: Conditions for stochastic integrability in UMD Banach spaces

abstract:
  A detailed theory of stochastic integration in UMD Banach spaces has been
developed recently by the authors. The present paper is aimed at giving various
sufficient conditions for stochastic integrability.


title: Periodic twisted cohomology and T-duality

abstract:
  The initial motivation of this work was to give a topological interpretation
of two-periodic twisted de-Rham cohomology which is generalizable to arbitrary
coefficients. To this end we develop a sheaf theory in the context of locally
compact topological stacks with emphasis on the construction of the sheaf
theory operations in unbounded derived categories, elements of Verdier duality
and integration. The main result is the construction of a functorial
periodization functor associated to a U(1)-gerbe. As applications we verify the
$T$-duality isomorphism in periodic twisted cohomology and in periodic twisted
orbispace cohomology.


title: Transport in randomly-fluctuating spatially-periodic potentials

abstract:
  The motion of overdamped particles in a one-dimensional spatially-periodic
potential is considered. The potential is also randomly-fluctuating in time,
due to multiplicative colored noise terms, and has a deterministic tilt.
Numerical aimulations show two distinct parameter regimes, corresponding to
free-running near-deterministic particles, and particles which are trapped in
local minima of the potential with intermittent escape flights. Perturbation
and asymptotic methods are developed to understand the drift velocity and
diffusion coefficient in each parameter regime.


title: Charges of dyons in N=2 supersymmetric gauge theory

abstract:
  Expressions for electric and magnetic charges of dyons, which become massless
in the strong-coupling limit of the supersymmetric N=2 gauge theory with an
arbitrary gauge group are presented. Transitions into different vacua of the N
=1 gauge theory, when the N=2 supersymmetry is broken explicitly to the N =1
case, are discussed. The existence of a minimal set of light dyons, which are
necessary to describe this transition, is established. The total number of
these dyons equals the product of the rank and dual Coxeter number of the gauge
group. A conjecture, which states that this minimal set incorporates all
possible light dyons, is discussed. A relation of dyon charges with monodromies
at weak and strong couplings is outlined and comparison with known charges of
dyons for particular gauge groups is made.


title:
A Study of Three Dimensional Edge and Corner Problems using the neBEM
  Solver

abstract:
  The previously reported neBEM solver has been used to solve electrostatic
problems having three-dimensional edges and corners in the physical domain.
Both rectangular and triangular elements have been used to discretize the
geometries under study. In order to maintain very high level of precision, a
library of C functions yielding exact values of potential and flux influences
due to uniform surface distribution of singularities on flat triangular and
rectangular elements has been developed and used. Here we present the exact
expressions proposed for computing the influence of uniform singularity
distributions on triangular elements and illustrate their accuracy. We then
consider several problems of electrostatics containing edges and singularities
of various orders including plates and cubes, and L-shaped conductors. We have
tried to show that using the approach proposed in the earlier paper on neBEM
and its present enhanced (through the inclusion of triangular elements) form,
it is possible to obtain accurate estimates of integral features such as the
capacitance of a given conductor and detailed ones such as the charge density
distribution at the edges / corners without taking resort to any new or special
formulation. Results obtained using neBEM have been compared extensively with
both existing analytical and numerical results. The comparisons illustrate the
accuracy, flexibility and robustness of the new approach quite comprehensively.


title: Preparation contextuality powers parity-oblivious multiplexing

abstract:
  In a noncontextual hidden variable model of quantum theory, hidden variables
determine the outcomes of every measurement in a manner that is independent of
how the measurement is implemented. Using a generalization of this notion to
arbitrary operational theories and to preparation procedures, we demonstrate
that a particular two-party information-processing task, "parity-oblivious
multiplexing," is powered by contextuality in the sense that there is a limit
to how well any theory described by a noncontextual hidden variable model can
perform. This bound constitutes a "noncontextuality inequality" that is
violated by quantum theory. We report an experimental violation of this
inequality in good agreement with the quantum predictions. The experimental
results also provide the first demonstration of 2-to-1 and 3-to-1 quantum
random access codes. Consequently, our experimental results also demonstrate
better-than-classical performance for this task. They also represent the first
demonstration of 2-to-1 and 3-to-1 quantum random access codes.


title:
Efficiently Simulating Higher-Order Arithmetic by a First-Order Theory
  Modulo

abstract:
  In deduction modulo, a theory is not represented by a set of axioms but by a
congruence on propositions modulo which the inference rules of standard
deductive systems---such as for instance natural deduction---are applied.
Therefore, the reasoning that is intrinsic of the theory does not appear in the
length of proofs. In general, the congruence is defined through a rewrite
system over terms and propositions. We define a rigorous framework to study
proof lengths in deduction modulo, where the congruence must be computed in
polynomial time. We show that even very simple rewrite systems lead to
arbitrary proof-length speed-ups in deduction modulo, compared to using axioms.
As higher-order logic can be encoded as a first-order theory in deduction
modulo, we also study how to reinterpret, thanks to deduction modulo, the
speed-ups between higher-order and first-order arithmetics that were stated by
G\"odel. We define a first-order rewrite system with a congruence decidable in
polynomial time such that proofs of higher-order arithmetic can be linearly
translated into first-order arithmetic modulo that system. We also present the
whole higher-order arithmetic as a first-order system without resorting to any
axiom, where proofs have the same length as in the axiomatic presentation.


title: The Drinfel'd polynomial of a tridiagonal pair

abstract:
  Let $K$ denote a field and let $V$ denote a vector space over $K$ with finite
positive dimension. We consider a pair of linear transformations $A:V \to V$
and $A^*:V \to V$ that satisfy the following conditions: (i) each of $A,A^*$ is
diagonalizable; (ii) there exists an ordering $\{V_i\}{i=0}^d$ of the
eigenspaces of $A$ such that $A^* V_i \subseteq V_{i-1} + V_{i} + V_{i+1}$ for
$0 \leq i \leq d$, where $V_{-1}=0$ and $V_{d+1}=0$; (iii) there exists an
ordering $\{V^*_i\}{i=0}^\delta$ of the eigenspaces of $A^*$ such that $A V^*_i
\subseteq V^*_{i-1} + V^*_{i} + V^*_{i+1}$ for $0 \leq i \leq \delta$, where
$V^*_{-1}=0$ and $V^*_{\delta+1}=0$; (iv) there is no subspace $W$ of $V$ such
that $AW \subseteq W$, $A^* W \subseteq W$, $W \neq 0$, $W \neq V$. We call
such a pair a {\it tridiagonal pair} on $V$. It is known that $d=\delta$ and
for $0 \leq i \leq d$ the dimensions of $V_i$, $V_{d-i}$, $V^*_i$, $V^*_{d-i}$
coincide. The pair $A,A^*$ is called {\it sharp} whenever $\dim V_0=1$. It is
known that if $K$ is algebraically closed then $A,A^*$ is sharp. Assuming
$A,A^*$ is sharp, we use the data $\Phi=(A; \{V_i\}{i=0}^d; A^*;
\{V^*_i\}{i=0}^d)$ to define a polynomial $P$ in one variable and degree at
most $d$. We show that $P$ remains invariant if $\Phi$ is replaced by
$(A;\{V_{d-i}\}{i=0}^d; A^*; \{V^*_i\}{i=0}^d)$ or $(A;\{V_i\}{i=0}^d; A^*;
\{V^*_{d-i}\}{i=0}^d)$ or $(A^*; \{V^*_i\}{i=0}^d; A; \{V_i\}{i=0}^d)$. We call
$P$ the {\it Drinfel'd polynomial} of $A,A^*$. We explain how $P$ is related to
the classical Drinfel'd polynomial from the theory of Lie algebras and quantum
groups. We expect that the roots of $P$ will be useful in a future
classification of the sharp tridiagonal pairs. We compute the roots of $P$ for
the case in which $V_i$ and $V^*_i$ have dimension 1 for $0 \leq i \leq d$.


title: The Iterative Simplicity of Basic Topological Operations

abstract:
  Semigroups generated by topological operations such as closure, interior or
boundary are considered. It is noted that some of these semigroups are in
general finite and noncommutative. The problem is formulated whether they are
always finite.


title: Two combinatorial formulas concerning marked partitions

abstract:
  A partition of degree $n$ is a decomposition $n=i_1+i_2+\dots+i_q$, where
${i_1,i_2,\dots,i_q}$ are positive integers called the parts of the partition.
Let $\lambda>0$ be an integer. The partition is said to be a
$\lambda$--partition if $i_{a+1}-i_a\geqslant \lambda$ for all $a$ such that
$1\leqslant a<q$.
  The main result of this note are combinatorial formulas, which express the
quantity of $1$-partitions of a given degree in terms of the
$\lambda$--partitions of the same degree, where $\lambda=2$ or $\lambda=3$,
some special parts of which are marked depending on $\lambda$. The presented
proofs of both formulas are bijective.
  It is shown that for $\lambda=3$ the corresponding formula is equivalent to
the classical Sylvester identity.
  The obtained combinatorial formulas as well as their bijective proofs are
generalized to the quantities of $1$--partitions, all parts of which are
$\geqslant k$ for any fixed integer $k\geqslant 1$.


title:
Greenberger-Horne-Zeilinger-type violation of local realism by mixed
  states

abstract:
  Cluster states are multi-particle entangled states with special entanglement
properties particularly suitable for quantum computation. It has been shown
that cluster states can exhibit Greenberger-Horne-Zeilinger (GHZ)-type
non-locality even when some of their qubits have been lost. In the present
work, we generated a four-photon mixed state, which is equivalent to the
partial, qubit-loss state of an N-qubit cluster state up to some local
transformations. By using this mixed state, we then realize a GHZ-type
violation of local realism. Our results not only demonstrate a mixed state's
GHZ-type non-locality but also exhibit the robustness of cluster states under
qubit-loss conditions.


title:
Automated detection of galaxy-scale gravitational lenses in high
  resolution imaging data

abstract:
  Lens modeling is the key to successful and meaningful automated strong
galaxy-scale gravitational lens detection. We have implemented a lens-modeling
"robot" that treats every bright red galaxy (BRG) in a large imaging survey as
a potential gravitational lens system. Using a simple model optimized for
"typical" galaxy-scale lenses, we generate four assessments of model quality
that are used in an automated classification. The robot infers the lens
classification parameter H that a human would have assigned; the inference is
performed using a probability distribution generated from a human-classified
training set, including realistic simulated lenses and known false positives
drawn from the HST/EGS survey. We compute the expected purity, completeness and
rejection rate, and find that these can be optimized for a particular
application by changing the prior probability distribution for H, equivalent to
defining the robot's "character." Adopting a realistic prior based on the known
abundance of lenses, we find that a lens sample may be generated that is ~100%
pure, but only ~20% complete. This shortfall is due primarily to the
over-simplicity of the lens model. With a more optimistic robot, ~90%
completeness can be achieved while rejecting ~90% of the candidate objects. The
remaining candidates must be classified by human inspectors. We are able to
classify lens candidates by eye at a rate of a few seconds per system,
suggesting that a future 1000 square degree imaging survey containing 10^7
BRGs, and some 10^4 lenses, could be successfully, and reproducibly, searched
in a modest amount of time. [Abridged]


title:
Low-energy cutoffs in electron spectra of solar flares: statistical
  survey

abstract:
  The Ramaty High Energy Solar Spectroscopic Imager (RHESSI) X-ray data base
(February 2002 -- May 2006) has been searched to find solar flares with weak
thermal components and flat photon spectra. Using a regularised inversion
technique, we determine the mean electron flux distribution from count spectra
of a selection of events with flat photon spectra in the 15--20 keV energy
range. Such spectral behaviour is expected for photon spectra either affected
by photospheric albedo or produced by electron spectra with an absence of
electrons in a given energy range, e.g. a low-energy cutoff in the mean
electron spectra of non-themal particles. We have found 18 cases which exhibit
a statistically significant local minimum (a dip) in the range of 10--20 keV.
The positions and spectral indices of events with low-energy cutoff indicate
that such features are likely to be the result of photospheric albedo. It is
shown that if the isotropic albedo correction was applied, all low-energy
cutoffs in the mean electron spectrum were removed and hence the low energy
cutoffs in the mean electron spectrum of solar flares above $\sim$12 keV cannot
be viewed as real features in the electron spectrum. If low-energy cutoffs
exist in the mean electron spectra, the energy of low energy cutoffs should be
less than $\sim$12 keV.


title: Entanglement of Quantum Fluctuations in the Inflationary Universe

abstract:
  We investigate quantum entanglement of a scalar field in the inflationary
universe. By introducing a bipartite system using a lattice model of scalar
field, we apply the separability criterion based on the partial transpose
operation and numerically calculate the bipartite entanglement between separate
spatial regions. We find that the initial entangled state becomes separable or
dis-entangled when the size of the spatial regions exceed the Hubble horizon.
This is necessary condition for the appearance of classicality of the quantum
fluctuation. We further investigate the condition for the appearance of the
classical distribution function and find that the condition is given by the
inequality for the symplectic eigenvalue of the covariance matrix of the scalar
field.


title:
Phonon dispersion curves of two-dimensional colloidal crystals: on the
  wavelength dependence of friction

abstract:
  Digital video-microscopy measurements are reported of both elastic
bandstructures and overdamped phonon decay times in two-dimensional colloidal
crystals. Both quantities together allow to determine the friction coefficients
along various high symmetry directions in q-space. These coefficients contain
valuable information on the hydrodynamic forces acting between the colloidal
particles. We find Stokes-like friction for phonons near the edge of the first
Brillouin zone and vanishing friction coefficients for long wavelength phonons.
The effect of this wavelength dependence in real-space is further investigated
by simulating a crystal with constant friction (Langevin simulation) and
comparing experimentally measured and simulated particle auto-correlation
functions.


title: A Fast Algorithm and Datalog Inexpressibility for Temporal Reasoning

abstract:
  We introduce a new tractable temporal constraint language, which strictly
contains the Ord-Horn language of Buerkert and Nebel and the class of AND/OR
precedence constraints. The algorithm we present for this language decides
whether a given set of constraints is consistent in time that is quadratic in
the input size. We also prove that (unlike Ord-Horn) this language cannot be
solved by Datalog or by establishing local consistency.


title: Three-loop results in HQET

abstract: Recent results and methods of three-loop calculations in HQET are reviewed.


title: Tuning the fragility of a glassforming liquid by curving space

abstract:
  We investigate the influence of space curvature, and of the associated
"frustration", on the dynamics of a model glassformer: a monatomic liquid on
the hyperbolic plane. We find that the system's fragility, i.e. the sensitivity
of the relaxation time to temperature changes, increases as one decreases the
frustration. As a result, curving space provides a way to tune fragility and
make it as large as wanted. We also show that the nature of the emerging
"dynamic heterogeneities", another distinctive feature of slowly relaxing
systems, is directly connected to the presence of frustration-induced
topological defects.


title:
Role of backflow correlations for the non-magnetic phase of the t-t'
  Hubbard model

abstract:
  We introduce an efficient way to improve the accuracy of projected wave
functions, widely used to study the two-dimensional Hubbard model. Taking the
clue from the backflow contribution, whose relevance has been emphasized for
various interacting systems on the continuum, we consider many-body
correlations to construct a suitable approximation for the ground state at
intermediate and strong couplings. In particular, we study the phase diagram of
the frustrated $t{-}t^\prime$ Hubbard model on the square lattice and show
that, thanks to backflow correlations, an insulating and non-magnetic phase can
be stabilized at strong coupling and sufficiently large frustrating ratio
$t^\prime/t$.


title:
Modelling of magnetic field structure of the Ergodic Divertor of Tore
  Supra and comparison to the Dynamic Ergodic Divertor of TEXTOR

abstract:
  An analytical model previously developed to study the structure of the
magnetic field for the TEXTOR-DED [S.S. Abdullaev et al. Phys. Plasmas, 6, 153
(1999)] is applied to the similar study of the Ergodic Divertor of Tore Supra
tokamak [Ph. Ghendrih, Plasma Phys. Control. Fusion, 38, 1653 (1996)]. The coil
configuration of ED Tore Supra consists of six modules equidistantly located
along the toroidal direction on the low-field-side of the torus with given
toroidal and poloidal extensions. The Hamiltonian formulation of field line
equations in straight-field-line coordinates (Boozer coordinates) and the
computationally efficient mapping method for integration of the Hamiltonian
field line equations are used to study the magnetic field structure in the ED.
Asymptotical formulas for the perturbation magnetic field created by the ED
coils are obtained and the spectrum of magnetic perturbations is analyzed and
compared with the one of the TEXTOR-DED. The structure of ergodic and laminar
zones are studied by plotting Poincare sections, so-called laminar plots
(contour plots of wall to wall connection lengths) and magnetic footprints. The
radial profiles of field line diffusion coefficients are calculated for
different perturbation currents and it is found that for the Tore Supra case in
the ergodic zone the numerical field line diffusion coefficients perfectly
follow the quasilinear formula for smaller perturbation currents although the
situation is different for the maximum perturbation current.


title: Fluctuations of the partition function in the GREM with external field

abstract:
  We study Derrida's generalized random energy model in the presence of uniform
external field. We compute the fluctuations of the ground state and of the
partition function in the thermodynamic limit for all admissible values of
parameters. We find that the fluctuations are described by a hierarchical
structure which is obtained by a certain coarse-graining of the initial
hierarchical structure of the GREM with external field. We provide an explicit
formula for the free energy of the model. We also derive some large deviation
results providing an expression for the free energy in a class of models with
Gaussian Hamiltonians and external field. Finally, we prove that the
coarse-grained parts of the system emerging in the thermodynamic limit tend to
have a certain optimal magnetization, as prescribed by strength of external
field and by parameters of the GREM.


title: Modular Reduction in Abstract Polytopes

abstract:
  The paper studies modular reduction techniques for abstract regular and
chiral polytopes, with two purposes in mind: first, to survey the literature
about modular reduction in polytopes; and second, to apply modular reduction,
with moduli given by primes in Z[t] (with t=\tau the golden ratio), to
construct new regular 4-polytopes of hyperbolic types {3,5,3} and {5,3,5} with
automorphism groups given by finite orthogonal groups.


title:
On-line Learning of an Unlearnable True Teacher through Mobile Ensemble
  Teachers

abstract:
  On-line learning of a hierarchical learning model is studied by a method from
statistical mechanics. In our model a student of a simple perceptron learns
from not a true teacher directly, but ensemble teachers who learn from the true
teacher with a perceptron learning rule. Since the true teacher and the
ensemble teachers are expressed as non-monotonic perceptron and simple ones,
respectively, the ensemble teachers go around the unlearnable true teacher with
the distance between them fixed in an asymptotic steady state. The
generalization performance of the student is shown to exceed that of the
ensemble teachers in a transient state, as was shown in similar
ensemble-teachers models. Further, it is found that moving the ensemble
teachers even in the steady state, in contrast to the fixed ensemble teachers,
is efficient for the performance of the student.


title:
Paraconsistent First-Order Logic with restricted modus ponens rule and
  infinite hierarchy levels of contradiction $LP^\#_{\omega}$. Axiomatical
  system $HST^\#_{\omega}$, as paraconsistent generalization of Hrbacek set
  theory HST

abstract:
  In this paper paraconsistent first-order logic LP^{#}_{\omega} with
restricted modus ponens rule and infinite hierarchy levels of contradiction is
proposed. Corresponding paraconsistent set theory KSth^{#}_{\omega} is
discussed.Axiomatical system HST^{#}_{\omega} as paraconsistent generalization
of Hrbacek set theory HST is considered.


title: Efficiency at maximum power of Feynman's ratchet as a heat engine

abstract:
  The maximum power of Feynman's ratchet as a heat engine and the corresponding
efficiency ($\eta_\ast$) are investigated by optimizing both the internal
parameter and the external load. When a perfect ratchet device (no heat
exchange between the ratchet and the paw via kinetic energy) works between two
thermal baths at temperatures $T_1> T_2$, its efficiency at maximum power is
found to be $\eta_\ast =\eta_C^2 /[\eta_C-(1-\eta_C)\ln(1-\eta_C)]$, where
$\eta_C\equiv 1-T_2/T_1$. This efficiency is slightly higher than the value
$1-\sqrt{T_2/T_1}$ obtained by Curzon and Ahlborn [\textit{Am. J. Phys.}
\textbf{43} (1975) 22] for macroscopic heat engines. It is also slightly larger
than the result $\eta_{SS}\equiv 2\eta_C/(4-\eta_C)$ obtained by Schmiedl and
Seifert [\textit{EPL} \textbf{81} (2008) 20003] for stochastic heat engines
working at small temperature difference, while the evident deviation between
$\eta_\ast$ and $\eta_{SS}$ appears at large temperature difference. For an
imperfect ratchet device in which the heat exchange between the ratchet and the
paw via kinetic energy is non-vanishing, the efficiency at maximum power
decreases with increasing the heat conductivity.


title: An Onsager-like Relation for the Lattice Boltzmann Method

abstract:
  An Onsager-like relation is proposed as a new criterion for constructing and
analysing the lattice Boltzmann (LB) method. For LB models obeying the
relation, we analyse their linearized stability, establish their diffusive
limit, and find new constraints for those with free parameters. The new
relation seems of fundamental importance for the LB method.


title: HBT interferometry with quantum transport of the interfering pair

abstract:
  In the late stage of the evolution of a pion system in high-energy heavy-ion
collisions when pions undergo multiple scatterings, the quantum transport of
the interfering pair of identical pions plays an important role in determining
the characteristics of the Hanbury-Brown-Twiss (HBT) interference. We study the
quantum transport of the interfering pair using the path-integral method, in
which the evolution of the bulk matter is described by relativistic
hydrodynamics while the paths of the two interfering pions by test particles
following the fluid positions and velocity fields. We investigate in addition
the effects of secondary pion sources from particle decays, for nuclear
collisions at AGS and RHIC energies. We find that quantum transport of the
interfering pair leads to HBT radii close to those for the chemical freeze-out
configuration. Particle decays however lead to HBT radii greater than those for
the chemical freeze-out configuration. As a consequence, the combined effects
give rise to HBT radii between those extracted from the chemical freeze-out
configuration and the thermal freeze-out configuration. Proper quantum
treatments of the interfering pairs in HBT calculations at the pion multiple
scattering stage are important for our understanding of the characteristics of
HBT interferometry in heavy-ion collisions.


title: Distributed MIMO Systems with Oblivious Antennas

abstract:
  A scenario in which a single source communicates with a single destination
via a distributed MIMO transceiver is considered. The source operates each of
the transmit antennas via finite-capacity links, and likewise the destination
is connected to the receiving antennas through capacity-constrained channels.
Targeting a nomadic communication scenario, in which the distributed MIMO
transceiver is designed to serve different standards or services, transmitters
and receivers are assumed to be oblivious to the encoding functions shared by
source and destination. Adopting a Gaussian symmetric interference network as
the channel model (as for regularly placed transmitters and receivers),
achievable rates are investigated and compared with an upper bound. It is
concluded that in certain asymptotic and non-asymptotic regimes obliviousness
of transmitters and receivers does not cause any loss of optimality.


title:
Obscured High Mass X-Ray Binaries and Supergiant Fast X-ray Transients:
  Infrared Observations of INTEGRAL Sources

abstract:
  A new type of high-energy binary system has been revealed by the INTEGRAL
satellite. These sources are being unveiled by means of multi-wavelength
optical, near- and mid-infrared observations. Among these sources, two distinct
classes are appearing: the first one is constituted of intrinsically obscured
high-energy sources, of which IGR J16318-4848 seems to be the most extreme
example. The second one is populated by the so-called supergiant fast X-ray
transients, with IGR J17544-2619 being the archetype. We report here on
multi-wavelength optical to mid-infrared observations of a sample constituted
of 21 INTEGRAL sources. We show that in the case of the obscured sources our
observations suggest the presence of absorbing material (dust and/or cold gas)
enshrouding the whole binary system. We finally discuss the nature of these two
different types of sources, in the context of high energy binary systems.


title: A Time Efficient Indexing Scheme for Complex Spatiotemporal Retrieval

abstract:
  The paper is concerned with the time efficient processing of spatiotemporal
predicates, i.e. spatial predicates associated with an exact temporal
constraint. A set of such predicates forms a buffer query or a Spatio-temporal
Pattern (STP) Query with time. In the more general case of an STP query, the
temporal dimension is introduced via the relative order of the spatial
predicates (STP queries with order). Therefore, the efficient processing of a
spatiotemporal predicate is crucial for the efficient implementation of more
complex queries of practical interest. We propose an extension of a known
approach, suitable for processing spatial predicates, which has been used for
the efficient manipulation of STP queries with order. The extended method is
supported by efficient indexing structures. We also provide experimental
results that show the efficiency of the technique.


title: Square-integrable coactions of locally compact quantum groups

abstract:
  We define and study square-integrable coactions of locally compact quantum
groups on Hilbert modules, generalising previous work for group actions. As
special cases, we consider square-integrable Hilbert space corepresentations
and integrable coactions on C*-algebras. Our main result is an equivariant
generalisation of Kasparov's Stabilisation Theorem.


title: Modeling and verifying a broad array of network properties

abstract:
  Motivated by widely observed examples in nature, society and software, where
groups of already related nodes arrive together and attach to an existing
network, we consider network growth via sequential attachment of linked node
groups, or graphlets. We analyze the simplest case, attachment of the three
node V-graphlet, where, with probability alpha, we attach a peripheral node of
the graphlet, and with probability (1-alpha), we attach the central node. Our
analytical results and simulations show that tuning alpha produces a wide range
in degree distribution and degree assortativity, achieving assortativity values
that capture a diverse set of many real-world systems. We introduce a
fifteen-dimensional attribute vector derived from seven well-known network
properties, which enables comprehensive comparison between any two networks.
Principal Component Analysis (PCA) of this attribute vector space shows a
significantly larger coverage potential of real-world network properties by a
simple extension of the above model when compared against a classic model of
network growth.

categories: cond-mat.stat-mech cs.SE q-bio.QM stat.AP


title:
2D and 3D Dense-Fluid Shear Flows via Nonequilibrium Molecular Dynamics.
  Comparison of Time-and-Space-Averaged Tensor Temperature and Normal Stresses
  from Doll's, Sllod, and Boundary-Driven Shear Algorithms

abstract:
  Homogeneous shear flows (with constant strainrate du/dy) are generated with
the Doll's and Sllod algorithms and compared to corresponding inhomogeneous
boundary-driven flows. We use one-, two-, and three-dimensional smooth-particle
weight functions for computing instantaneous spatial averages. The nonlinear
stress differences are small, but significant, in both two and three space
dimensions. In homogeneous systems the sign and magnitude of the shearplane
stress difference, P(xx) - P(yy), depend on both the thermostat type and the
chosen shearflow algorithm. The Doll's and Sllod algorithms predict opposite
signs for this stress difference, with the Sllod approach definitely wrong, but
somewhat closer to the (boundary-driven) truth. Neither of the homogeneous
shear algorithms predicts the correct ordering of the kinetic temperatures,
T(xx) > T(zz) > T(yy).


title:
ASTE CO(3--2) Observations of the Southern Barred Spiral Galaxy NGC 986:
  a Large Gaseous Bar Filled with Dense Molecular Medium

abstract:
  We present CO(3-2) emission observations toward the 3'x3' (or 20x20kpc at a
distance of 23Mpc) region of the southern barred spiral galaxy NGC 986 using
the Atacama Submillimeter Telescope Experiment (ASTE). This effort is a part of
our on-going extragalactic CO(3-2) imaging project ADIoS (ASTE Dense gas
Imaging of Spiral galaxies). Our CO(3-2) image revealed the presence of a large
(the major axis is 14 kpc in total length) gaseous bar filled with dense
molecular medium along the dark lanes observed in optical images. This is the
largest ``dense-gas rich bar'' known to date. The dense gas bar discovered in
NGC 986 could be a huge reservoir of possible ``fuel'' for future starbursts in
the central region, and we suggest that the star formation in the central
region of NGC 986 could still be in a growing phase. We found a good spatial
coincidence between the overall distributions of dense molecular gas traced by
CO(3-2) and the massive star formation depicted by H$\alpha$. The global
CO(3-2) luminosity $L'_{\rm CO(3-2)}$ of NGC 986 was determined to be $(5.4 \pm
1.1) \times 10^8$ K km s$^{-1}$ pc$^2$. The CO(3-2)/CO(1-0) integrated
intensity ratio was found to be 0.60 +/- 0.13 at a spatial resolution of 44''
or 5 kpc, and a CO(3-2)/CO(2-1) ratio was 0.67 +/- 0.14 at a beam size of ~25''
or ~2.8 kpc. These line ratios suggest moderate excitation conditions of CO
lines ($n_{\rm H_2} \sim 10^{3-4}$ cm$^{-3}$) in the central a few kpc region
of NGC 986.