title:
Structures and Transformations for Model Reduction of Linear Quantum
  Stochastic Systems

abstract:
  The purpose of this paper is to develop a model reduction theory for linear
quantum stochastic systems that are commonly encountered in quantum optics and
related fields, modeling devices such as optical cavities and optical
parametric amplifiers, as well as quantum networks composed of such devices.
Results are derived on subsystem truncation of such systems and it is shown
that this truncation preserves the physical realizability property of linear
quantum stochastic systems. It is also shown that the property of complete
passivity of linear quantum stochastic systems is preserved under subsystem
truncation. A necessary and sufficient condition for the existence of a
balanced realization of a linear quantum stochastic system under sympletic
transformations is derived. Such a condition turns out to be very restrictive
and will not be satisfied by generic linear quantum stochastic systems, thus
necessary and sufficient conditions for relaxed notions of simultaneous
diagonalization of the controllability and observability Gramians of linear
quantum stochastic systems under symplectic transformations are also obtained.
The notion of a quasi-balanced realization is introduced and it is shown that
all asymptotically stable completely passive linear quantum stochastic systems
have a quasi-balanced realization. Moreover, an explicit bound for the
subsystem truncation error on a quasi-balanceable linear quantum stochastic
system is provided. The results are applied in an example of model reduction in
the context of low-pass optical filtering of coherent light using a network of
optical cavities.


title:
Importance of complex orbitals in calculating the
  self-interaction-corrected ground state of atoms

abstract:
  The ground state of atoms from H to Ar was calculated using a
self-interaction correction to local and gradient dependent density
functionals. The correction can significantly improve the total energy and
makes the orbital energies consistent with ionization energies. However, when
the calculation is restricted to real orbitals, application of the
self-interaction correction can give significantly higher total energy and
worse results, as illustrated by the case of the Perdew-Burke-Ernzerhof
gradient dependent functional. This illustrates the importance of using complex
orbitals for systems described by orbital density dependent energy functionals.

categories: physics.atm-clus physics.atom-ph physics.chem-ph quant-ph


title:
Measurement of the differential dijet production cross section in
  proton-proton collisions at \sqrt{s} = 7 tev

abstract:
  A measurement of the double-differential inclusive dijet production cross
section in proton-proton collisions at \sqrt{s}= 7 TeV is presented as a
function of the dijet invariant mass and jet rapidity. The data correspond to
an integrated luminosity of 36 pb^{-1}, recorded with the CMS detector at the
LHC in 2010. The measurement covers the dijet mass range 0.2 TeV to 3.5 TeV and
jet rapidities up to |y|=2.5. It is found to be in good agreement with
next-to-leading-order QCD predictions.


title: Violation of no signaling in higher order quantum measure theories

abstract:
  More general probability sum-rules for describing interference than found in
quantum mechanics (QM) were formulated by Sorkin in a hierarchy of such rules.
The additivity of classical measure theory corresponds to the second sum-rule.
QM violates this rule, but satisfies the third and higher sum-rules. This
evokes the question of whether there are physical principles that forbid their
violation. We show that under certain assumptions, violation of higher
sum-rules allows for superluminal signaling.


title:
Nonequilibrium "melting" of a charge density wave insulator via an
  ultrafast laser pulse

abstract:
  We employ an exact solution of the simplest model for pump-probe
time-resolved photoemission spectroscopy in charge-density-wave systems to show
how, in nonequilibrium the gap in the density of states disappears while the
charge density remains modulated, and then the gap reforms after the pulse has
passed. This nonequilibrium scenario qualitatively describes the common
short-time experimental features in TaS2 and TbTe3 indicating a
quasiuniversality for nonequilibrium "melting" with qualitative features that
can be easily understood within a simple picture.


title: Sealed States And Quantum Blackmail

abstract:
  Consider a protocol in which Belinda seals a (classical) message. She gives
the resulting sealed message to Charlie, who can either unseal and read the
message or return it unopened to Belinda. If he returns it unopened, Belinda
should be able to verify that Charlie neither read the message nor made a copy
that would allow him to read it later. Such a protocol is impossible with
classical cryptography: Charlie can copy a message and do anything he likes to
that copy without damaging the original. With quantum cryptography, on the
other hand, the no cloning theorem implies that Charlie cannot simply copy a
message and unseal the copy.
  Abstract In this paper, I prove that any conventional quantum cryptographic
protocol can give at best a very weak security guarantee. However, quantum
cryptography in conjunction with classical functions that can only be inverted
by humans (i.e. CAPTCHAs) can potentially give exponential security.


title: Constraining cosmic string parameters with curl mode of CMB lensing

abstract:
  We present constraints on a cosmic string network with a measurement of weak
gravitational lensing from CMB temperature map. The cosmic string network
between observer and last scattering surface of CMB photons generates vector
and/or tensor metric perturbations, and the deflection of CMB photons by these
gravitational fields has curl mode which is not produced by the scalar metric
perturbations. In this paper, we use the power spectrum of curl mode obtained
from Planck to constrain the string tension, G\mu, and the reconnection
probability, P. In demonstrating the parameter constraints with Planck curl
mode, we also measure the lensing power spectrum from the Atacama Cosmology
Telescope (ACT) 2008 season data, which have better angular resolution with
lower instrumental noise on a much smaller chunk of the sky. Assuming P=1, the
upper bound on tension is G\mu = 6.6\times 10^{-5} with 2\sigma (95% C.L.),
using curl mode from Planck, which is weaker than that from the small-scale
temperature power spectrum. For small values of P, however, the constraint from
curl mode becomes tighter compared to that from temperature power spectrum. For
P\lsim 10^{-2}, we obtain the constraint on the combination of the string
parameters as G\mu P^{-1}\leq 3.4\times 10^{-5} at more than 2\sigma (95%
C.L.).


title:
Compound Poisson Processes, Latent Shrinkage Priors and Bayesian
  Nonconvex Penalization

abstract:
  In this paper we discuss Bayesian nonconvex penalization for sparse learning
problems. We explore a nonparametric formulation for latent shrinkage
parameters using subordinators which are one-dimensional L\'{e}vy processes. We
particularly study a family of continuous compound Poisson subordinators and a
family of discrete compound Poisson subordinators. We exemplify four specific
subordinators: Gamma, Poisson, negative binomial and squared Bessel
subordinators. The Laplace exponents of the subordinators are Bernstein
functions, so they can be used as sparsity-inducing nonconvex penalty
functions. We exploit these subordinators in regression problems, yielding a
hierarchical model with multiple regularization parameters. We devise ECME
(Expectation/Conditional Maximization Either) algorithms to simultaneously
estimate regression coefficients and regularization parameters. The empirical
evaluation of simulated data shows that our approach is feasible and effective
in high-dimensional data analysis.


title: The Synergy between Weak Lensing and Galaxy Redshift Surveys

abstract:
  We study the complementarity of weak lensing (WL) and spectroscopic galaxy
clustering (GC) surveys, by forecasting dark energy and modified gravity
constraints for three upcoming survey combinations: SuMIRe (Subaru Measurement
of Images and Redshifts, the combination of the Hyper Suprime-Cam lensing
survey and the Prime Focus Spectrograph redshift survey), EUCLID and WFIRST.
From the WL surveys, we take into account both the shear and clustering of the
source galaxies and from the GC surveys, we use the three-dimensional
clustering of spectroscopic galaxies, including redshift space distortions. A
CMB prior is included in all cases. Focusing on the large-scale, two-point
function information, we find strong synergy between the two probes. The dark
energy figure of merit from WL+GC is up to a factor ~2.5 larger than from
either probe alone. Considering modified gravity, if the growth factor f(z) is
treated as a free function, it is very poorly constrained by WL or GC alone,
but can be measured at the few percent level by the combination of the two. On
the other hand, for cosmological constraints derived from (angular) power
spectra and considering statistical errors only, it hardly matters whether the
surveys overlap on the sky or not. For instance, the dark energy figure of
merit for overlapping surveys is at most ~20 % better than in the disjoint
case. This modest gain can be traced to the fundamental fact that only a small
fraction of the total number of modes sampled by the GC survey (or by the WL
survey) contributes to the cross-correlations between WL and GC.


title: Multilepton Higgs Decays through the Dark Portal

abstract:
  The U(1)_D gauge sector containing one dark Higgs boson h_D and one dark
photon \gamma_D may be explored through the decays of the 126 GeV particle
discovered at the Large Hadron Collider (LHC), assumed here as the heavier mass
eigenstate h_1 in the mixing of the standard model h with h_D. The various
decays of h_1 to \gamma_D \gamma_D, h_2 h_2, h_2 \gamma_D \gamma_D and h_2 h_2
h_2 would yield multilepton final states through the mixing of \gamma_D with
the photon and the decay h_2 \to \gamma_D \gamma_D, where h_2 is the lighter
dark Higgs. Future searches for signals of multilepton jets at the LHC may
reveal the existence of this possible dark sector governed simply by the
original Abelian Higgs model.


title:
Some properties of the de Sitter black holes in three dimensional
  spacetime

abstract:
  We investigate the physical properties of the de Sitter spacetime and new
type-de Sitter black holes in new massive gravity, a higher derivative gravity
theory in three dimensions. We calculate thermodynamic quantities and check
that the first law of thermodynamics is satisfied. In particular, we obtain the
energies of the de Sitter spacetime and new type-de Sitter black holes from the
renormalized Brown-York boundary stress tensor on the Euclidean surfaces at
late temporal infinity. We also obtain the quasinormal modes and by using them
we find that the entropy spectra are equally spaced via semi-classical
quantization.


title:
Simple implementation of quantum delayed-choice experiment using
  conventional linear optical elements

abstract:
  We propose a simple implementation scheme of quantum delayed-choice
experiment in linear optical system without initial entanglement resource. By
choosing different detecting devices, one can selectively observe the photon's
different behaviors after the photon has been passed the Mach-Zehnder
interferometer. The scheme shows that the photon's wave behavior and particle
behavior can be observed with a single experimental setup by postselection,
that is, the photon can show the superposition behavior of wave and particle.
Especially, we compare the wave-particle superposition behavior and the
wave-particle mixture behavior in detail, and find the quantum interference
effect between wave and particle behavior, which may be helpful to reveal the
nature of photon essentially.


title: Exploration and retrieval of whole-metagenome sequencing samples

abstract:
  Over the recent years, the field of whole metagenome shotgun sequencing has
witnessed significant growth due to the high-throughput sequencing technologies
that allow sequencing genomic samples cheaper, faster, and with better coverage
than before. This technical advancement has initiated the trend of sequencing
multiple samples in different conditions or environments to explore the
similarities and dissimilarities of the microbial communities. Examples include
the human microbiome project and various studies of the human intestinal tract.
With the availability of ever larger databases of such measurements, finding
samples similar to a given query sample is becoming a central operation. In
this paper, we develop a content-based exploration and retrieval method for
whole metagenome sequencing samples. We apply a distributed string mining
framework to efficiently extract all informative sequence $k$-mers from a pool
of metagenomic samples and use them to measure the dissimilarity between two
samples. We evaluate the performance of the proposed approach on two human gut
metagenome data sets as well as human microbiome project metagenomic samples.
We observe significant enrichment for diseased gut samples in results of
queries with another diseased sample and very high accuracy in discriminating
between different body sites even though the method is unsupervised. A software
implementation of the DSM framework is available at
https://github.com/HIITMetagenomics/dsm-framework


title: Measuring the dimension of partially embedded networks

abstract:
  Scaling phenomena have been intensively studied during the past decade in the
context of complex networks. As part of these works, recently novel methods
have appeared to measure the dimension of abstract and spatially embedded
networks. In this paper we propose a new dimension measurement method for
networks, which does not require global knowledge on the embedding of the
nodes, instead it exploits link-wise information (link lengths, link delays or
other physical quantities). Our method can be regarded as a generalization of
the spectral dimension, that grasps the network's large-scale structure through
local observations made by a random walker while traversing the links. We apply
the presented method to synthetic and real-world networks, including road maps,
the Internet infrastructure and the Gowalla geosocial network. We analyze the
theoretically and empirically designated case when the length distribution of
the links has the form P(r) ~ 1/r. We show that while previous dimension
concepts are not applicable in this case, the new dimension measure still
exhibits scaling with two distinct scaling regimes. Our observations suggest
that the link length distribution is not sufficient in itself to entirely
control the dimensionality of complex networks, and we show that the proposed
measure provides information that complements other known measures.


title:
Oscillation death in diffusively coupled oscillators by local repulsive
  link

abstract:
  A death of oscillation is reported in a network of coupled synchronized
oscillators in presence of additional repulsive coupling. The repulsive link
evolves as an averaging effect of mutual interaction between two neighboring
oscillators due to a local fault and the number of repulsive links grows in
time when the death scenario emerges. Analytical condition for oscillation
death is derived for two coupled Landau-Stuart systems. Numerical results also
confirm oscillation death in chaotic systems such as a Sprott system and the
R\"ossler oscillator. We explore the effect in large networks of globally
coupled oscillators and find that the number of repulsive links is always fewer
than the size of the network.


title: Multipartite entangled light from driven microcavities

abstract:
  The generation and the characterization of multipartite entangled light is an
important and challenging task in quantum optics. In this paper the
entanglement properties of the light emitted from a planar semiconductor
microcavity are studied. The intracavity scattering dynamics leads to the
emission of light that is described by a fourpartite W state. Its multipartite
correlations are identified by using the method of entanglement witnesses.
Entanglement conditions are derived, which are based on a general witness
constructed from W states. The results can be used to detect entanglement of
light that propagates through lossy and even turbulent media.


title:
Static magnetic field concentration and enhancement using magnetic
  materials with positive permeability

abstract:
  In this paper a novel compressor for static magnetic fields is proposed based
on finite embedded transformation optics. When the DC magnetic field passes
through the designed device, the magnetic field can be compressed inside the
device. After it passes through the device, one can obtain an enhanced static
magnetic field behind the output surface of the device (in a free space
region). We can also combine our compressor with some other structures to get a
higher static magnetic field enhancement in a free space region. In contrast
with other devices based on transformation optics for enhancing static magnetic
fields, our device is not a closed structure and thus has some special
applications (e.g., for controlling magnetic nano-particles for gene and drag
delivery). The designed compressor can be constructed by using currently
available materials or DC meta-materials with positive permeability. Numerical
simulation verifies good performance of our device.


title:
Effects of disorder and contacts on transport through graphene
  nanoribbons

abstract:
  We study the transport of charge carriers through finite graphene structures.
The use of numerical exact kernel polynomial and Green function techniques
allows us to treat actual sized samples beyond the Dirac-cone approximation.
Particularly we investigate disordered nanoribbons, normal-conductor/graphene
interfaces and normal-conductor/graphene/normal-conductor junctions with a
focus on the behavior of the local density of states, single-particle spectral
function, optical conductivity and conductance. We demonstrate that the
contacts and bulk disorder will have a major impact on the electronic
properties of graphene-based devices.


title:
Study of bound states in 12Be through low-energy 11Be(d,p)-transfer
  reactions

abstract:
  The bound states of 12Be have been studied through a 11Be(d,p)12Be transfer
reaction experiment in inverse kinematics. A 2.8 MeV/u beam of 11Be was
produced using the REX-ISOLDE facility at CERN. The outgoing protons were
detected with the T-REX silicon detector array. The MINIBALL germanium array
was used to detect gamma rays from the excited states in 12Be. The gamma-ray
detection enabled a clear identification of the four known bound states in
12Be, and each of the states has been studied individually. Differential cross
sections over a large angular range have been extracted. Spectroscopic factors
for each of the states have been determined from DWBA calculations and have
been compared to previous experimental and theoretical results.


title:
Toward finding gravitational-wave signals from progenitors of short hard
  gamma-ray bursts and orphaned afterglows

abstract:
  With multiple observatories and missions being planned for detecting orphaned
afterglows associated with gamma-ray bursts (GRBs) we emphasize the importance
of developing data analysis strategies for searching their possible counterpart
signals in the data of gravitational wave (GW) detectors in the advanced
detector era. This is especially attractive since short hard gamma-ray bursts
(SGRBs) may have compact binary coalescences involving neutron stars (CBCNSs)
as their progenitors, which emit gravitational waves. Joint electromagnetic
(EM) and GW observations of these objects will enrich our understanding of
their beaming, energetics, galactic environment, and shed light on a host of
other outstanding questions related to them. Here we recognize some of the
astrophysical factors that determine what fraction of CBCNS sources can
generate orphaned afterglows. Pipelines already exist that target the
sky-position and time of occurrence of SGRBs, known from EM observations, to
search for their counterparts in GW detector data. Modifying them to analyze
extended periods of time in the GW data in the past of the afterglow detection,
while targeting a single sky-position, can search for GWs from the common
progenitor. We assess the improvement in GW detectability to be had from
utilizing the sky-position information. We also propose a method for improving
the detection efficiency of targeted searches of GW signals from the putative
CBCNS sources of afterglows and short gamma ray bursts in the presence of
errors in detector calibration or CBCNS waveform models used in the search. The
improvement arises from searching in a wider patch of the sky even when the
sky-position is known accurately from EM observations and utilizes the
covariance of the errors in waveform parameters with those in the sky position.


title:
Singular vorticity solutions of the incompressible Euler equation via
  inviscid limits

abstract:
  Singular vorticty solutions of the incompressible 3D-Euler equation are
constructed which satisfy the BKM criterion (cf. [2]). The construction is done
by inviscid limits of vorticity solutions of transformed incompressible Navier
Stokes type equations with a damping potential term, where the latter equations
admit a global regular solution for positive viscosity. The inviscid limit
vorticity solution of the incompressible Euler vorticity equation becomes
singular at a point of the boundary of a finite domain.


title: Optimising NGAS for the MWA Archive

abstract:
  The Murchison Widefield Array (MWA) is a next-generation radio telescope,
generating visibility data products continuously at about 400 MB/s. Efficiently
managing and archiving this data is a challenge. The MWA Archive consists of
dataflows and storage sub-systems distributed across three tiers. At its core
is the open source software - the Next-Generation Archive System (NGAS) - that
was initially developed in ESO. However, to meet the MWA data challenge, we
have tailored and optimised NGAS to achieve high-throughput data ingestion,
efficient dataflow management, multi-tiered data storage and processing-aware
data staging.


title:
Mechanism of formation and peculiarities of structure of bulk MgB2
  compound specimens

abstract:
  The existence of two phases within one and the same hexagonal lattice of MgB2
compound, differing in Mg and B (in the homogeneity region) and especially in
impurity oxygen content, as well as in microstructure, is demonstrated by
various techniques. The regions corresponding to these two phases of MgB2 have
the sizes of 100-500 {\mu}m, and they fill the whole bulk of specimens,
alternating with each other. It is suggested that the two-phase state of MgB2
compound is caused by specific features of its formation mechanism (as a result
of synthesis at 800-1000{\deg}C), including the stages of Mg melting,
dissolution of solid boron in it up to the composition of MgB2 and further
crystallization of the MgB2 compound from the melt with the formation of
dendrite-like structure with corresponding redistribution of main components
and impurities.


title: Characterization of Large Volume 3.5 x 8 inches LaBr3:Ce Detectors

abstract:
  The properties of large volume cylindrical 3.5 x 8 inches (89 mm x 203 mm)
LaBr3:Ce scintillation detectors coupled to the Hamamatsu R10233-100SEL
photo-multiplier tube were investigated. These crystals are among the largest
ones ever produced and still need to be fully characterized to determine how
these detectors can be utilized and in which applications. We tested the
detectors using monochromatic gamma-ray sources and in-beam reactions producing
gamma rays up to 22.6 MeV; we acquired PMT signal pulses and calculated
detector energy resolution and response linearity as a function of gamma-ray
energy. Two different voltage dividers were coupled to the Hamamatsu
R10233-100SEL PMT: the Hamamatsu E1198-26, based on straightforward resistive
network design, and the LABRVD, specifically designed for our large volume
LaBr3:Ce scintillation detectors, which also includes active semiconductor
devices. Because of the extremely high light yield of LaBr3:Ce crystals we
observed that, depending on the choice of PMT, voltage divider and applied
voltage, some significant deviation from the ideally proportional response of
the detector and some pulse shape deformation appear. In addition, crystal
non-homogeneities and PMT gain drifts affect the (measured) energy resolution
especially in case of high-energy gamma rays. We also measured the time
resolution of detectors with different sizes (from 1x1 inches up to 3.5x8
inches), correlating the results with both the intrinsic properties of PMTs and
GEANT simulations of the scintillation light collection process. The detector
absolute full energy efficiency was measured and simulated up to gamma-rays of
30 MeV


title: Distributed Compressed Sensing For Static and Time-Varying Networks

abstract:
  We consider the problem of in-network compressed sensing from distributed
measurements. Every agent has a set of measurements of a signal $x$, and the
objective is for the agents to recover $x$ from their collective measurements
using only communication with neighbors in the network. Our distributed
approach to this problem is based on the centralized Iterative Hard
Thresholding algorithm (IHT). We first present a distributed IHT algorithm for
static networks that leverages standard tools from distributed computing to
execute in-network computations with minimized bandwidth consumption. Next, we
address distributed signal recovery in networks with time-varying topologies.
The network dynamics necessarily introduce inaccuracies to our in-network
computations. To accommodate these inaccuracies, we show how centralized IHT
can be extended to include inexact computations while still providing the same
recovery guarantees as the original IHT algorithm. We then leverage these new
theoretical results to develop a distributed version of IHT for time-varying
networks. Evaluations show that our distributed algorithms for both static and
time-varying networks outperform previously proposed solutions in time and
bandwidth by several orders of magnitude.


title:
On the Systematic Errors of Cosmological-Scale Gravity Tests using
  Redshift Space Distortion: Non-linear Effects and the Halo Bias

abstract:
  Redshift space distortion (RSD) observed in galaxy redshift surveys is a
powerful tool to test gravity theories on cosmological scales, but the
systematic uncertainties must carefully be examined for future surveys with
large statistics. Here we employ various analytic models of RSD and estimate
the systematic errors on measurements of the structure growth-rate parameter,
$f\sigma_8$, induced by non-linear effects and the halo bias with respect to
the dark matter distribution, by using halo catalogues from 40 realisations of
$3.4 \times 10^8$ comoving $h^{-3}$Mpc$^3$ cosmological N-body simulations. We
consider hypothetical redshift surveys at redshifts z=0.5, 1.35 and 2, and
different minimum halo mass thresholds in the range of $5.0 \times 10^{11}$ --
$2.0 \times 10^{13} h^{-1} M_\odot$. We find that the systematic error of
$f\sigma_8$ is greatly reduced to ~5 per cent level, when a recently proposed
analytical formula of RSD that takes into account the higher-order coupling
between the density and velocity fields is adopted, with a scale-dependent
parametric bias model. Dependence of the systematic error on the halo mass, the
redshift, and the maximum wavenumber used in the analysis is discussed. We also
find that the Wilson-Hilferty transformation is useful to improve the accuracy
of likelihood analysis when only a small number of modes are available in power
spectrum measurements.


title:
The insidious boosting of TP-AGB stars in intermediate-age Magellanic
  Cloud clusters

abstract:
  (Abridged) In the recent controversy about the role of TP-AGB stars in
evolutionary population synthesis (EPS) models of galaxies, one particular
aspect is puzzling: TP-AGB models aimed at reproducing the lifetimes and
integrated fluxes of the TP-AGB phase in Magellanic Cloud (MC) clusters, when
incorporated into EPS models, are found to overestimate the TP-AGB contribution
in resolved star counts and integrated spectra of galaxies. In this paper, we
call attention to a particular evolutionary aspect that in all probability is
the main cause of this conundrum. As soon as stellar populations intercept the
ages at which RGB stars first appear, a sudden change in the lifetime of the
core He-burning phase causes a temporary boost in the production rate of
subsequent evolutionary phases, including the TP-AGB. For a timespan of about
0.1 Gyr, triple TP-AGB branches develop at slightly different initial masses,
causing their frequency and contribution to the integrated luminosity of the
stellar population to increase by a factor of 2. The boost occurs just in the
proximity of the expected peak in the TP-AGB lifetimes, and for ages of 1.6
Gyr. Coincidently, this relatively narrow age interval happens to contain the
few very massive MC clusters that host most of the TP-AGB stars used to
constrain stellar evolution and EPS models. This concomitance makes the
AGB-boosting particularly insidious in the context of present EPS models. The
effect brings about three main consequences. (1) Present estimates of the
TP-AGB contribution to the integrated light of galaxies derived from MC
clusters, are biased towards too large values. (2) The relative TP-AGB
contribution of single-burst populations falling in this critical age range
cannot be accurately derived by the fuel consumption theorem. (3) A careful
revision of AGB star populations in intermediate-age MC clusters is urgently
demanded.


title: Graded modules over classical simple Lie algebras with a grading

abstract:
  Given a grading by an abelian group G on a semisimple Lie algebra L over an
algebraically closed field of characteristic 0, we classify up to isomorphism
the simple objects in the category of finite-dimensional G-graded L-modules.
The invariants appearing in this classification are computed in the case when L
is simple classical (except for type D4, where a partial result is given). In
particular, we obtain criteria to determine when a finite-dimensional simple
L-module admits a G-grading making it a graded L-module.


title: Asymptotic control theory for a system of linear oscillators

abstract:
  We present an asymptotic control theory for a system of an arbitrary number
of linear oscillators under a common bounded control. We suggest a design
method of a feedback control for this system. By using the DiPerna-Lions theory
of singular ODEs, we prove that the suggested control law correctly defines the
motion of the system. The obtained control is asymptotically optimal: the ratio
of the motion time to zero under this control to the minimum one is close to 1
if the initial energy of the system is large. The results are partially based
on a new perturbation theory of observable linear systems.


title:
Suzaku Studies of Luminosity-Dependent Changes in the Low-Mass X-ray
  Binary Aquila X-1

abstract:
  The neutron-star Low-Mass X-ray Binary Aquila X-1 was observed by Suzaku for
seven times, from 2007 September 28 to October 30. The observations
successfully traced an outburst decay in which the source luminosity decreased
almost monotonically from $\sim 10^{37}$ erg s$^{-1}$ to $\sim 10^{34}$ erg
s$^{-1}$, by $\sim 3$ orders of magnitude. To investigate luminosity-dependent
changes in the accretion geometry, five of the seven data sets with a typical
exposure of $\sim 18$ ks each were analyzed; the other two were utilized in a
previous work \citep{Sakurai2012}. The source was detected up to 100 keV in the
2nd to the 4th observations, to 40 keV in the 5th, and to 10 keV on the last
two occasions. All spectra were reproduced successfully by Comptonized
blackbody model with relatively high ($\gtrsim 2.0$) optical depths, plus an
additional softer optically-thick component. The faintest three spectra were
reproduced alternatively by a single Comptonized blackbody model with a
relatively low ($\lesssim 0.8$) optical depth. The estimated radius of the
blackbody emission, including seed photons for the Comptonization, was $10 \pm
2$ km at a 0.8--100 keV luminosity of $2.4\times 10^{36}$ erg s$^{-1}$ (the 2nd
to the 4th observations). In contrast, it decreased to $7 \pm 1$ km and further
to $3 \pm 1$ km, at a luminosity of $(4.8-5.2)\times 10^{35}$ erg s$^{-1}$ (the
5th observation) and $\sim 2\times 10^{34}$ erg s$^{-1}$ (the 6th and 7th),
respectively, regardless of the above model ambiguity. This can be taken as
evidence for the emergence of a weak magnetosphere of the neutron star.


title: Quantum Metrology with Cold Atoms

abstract:
  Quantum metrology is the science that aims to achieve precision measurements
by making use of quantum principles. Attribute to the well-developed techniques
of manipulating and detecting cold atoms, cold atomic systems provide an
excellent platform for implementing precision quantum metrology. In this
chapter, we review the general procedures of quantum metrology and some
experimental progresses in quantum metrology with cold atoms. Firstly, we give
the general framework of quantum metrology and the calculation of quantum
Fisher information, which is the core of quantum parameter estimation. Then, we
introduce the quantum interferometry with single and multiparticle states. In
particular, for some typical multiparticle states, we analyze their ultimate
precision limits and show how quantum entanglement could enhance the
measurement precision beyond the standard quantum limit. Further, we review
some experimental progresses in quantum metrology with cold atomic systems.


title: Disorder-induced regular dynamics in oscillating lattices

abstract:
  We explore the impact of weak disorder on the dynamics of classical particles
in a periodically oscillating lattice. It is demonstrated that the disorder
induces a hopping process from diffusive to regular motion i.e. we observe the
counterintuitive phenomenon that disorder leads to regular behaviour. If the
disorder is localized in a finite-sized part of the lattice, the described
hopping causes initially diffusive particles to even accumulate in regular
structures of the corresponding phase space. A hallmark of this accumulation is
the emergence of pronounced peaks in the velocity distribution of particles
which should be detectable in state of the art experiments e.g. with cold atoms
in optical lattices.


title:
Interaction driven phases in the honeycomb lattice from exact
  diagonalization

abstract:
  We investigate the fate of interaction driven phases in the half-filled
honeycomb lattice for finite systems via exact diagonalization with nearest and
next nearest neighbour interactions. We find evidence for a charge density wave
phase, a Kekul\'e bond order and a sublattice charge modulated phase in
agreement with previously reported mean-field phase diagrams. No clear sign of
an interaction driven Chern insulator phase (Haldane phase) is found despite
being predicted by the same mean-field analysis. We characterize these phases
by their ground state degeneracy and by calculating charge order and bond order
correlation functions.


title:
Early Afterglows of Gamma-Ray Bursts in a Stratified Medium with a
  Power-Law Density Distribution

abstract:
  A long-duration gamma-ray burst (GRB) has been widely thought to arise from
the collapse of a massive star, and it has been suggested that its ambient
medium is a homogenous interstellar medium (ISM) or a stellar wind. There are
two shocks when an ultra-relativistic fireball that has been ejected during the
prompt gamma-ray emission phase sweeps up the circumburst medium: a reverse
shock that propagates into the fireball, and a forward shock that propagates
into the ambient medium. In this paper, we investigate the temporal evolution
of the dynamics and emission of these two shocks in an environment with a
general density distribution of $n\propto R^{-k}$ (where $R$ is the radius) by
considering thick-shell and thin-shell cases. A GRB afterglow with one smooth
onset peak at early times is understood to result from such external shocks.
Thus, we can determine the medium density distribution by fitting the onset
peak appearing in the light curve of an early optical afterglow. We apply our
model to 19 GRBs, and find that their $k$ values are in the range of 0.4 - 1.4,
with a typical value of $k\sim1$, implying that this environment is neither a
homogenous interstellar medium with $k=0$ nor a typical stellar wind with
$k=2$. This shows that the progenitors of these GRBs might have undergone a new
mass-loss evolution.


title: Micro Spitbol

abstract:
  A compact version of MACRO SPITBOL, a compiler/ interpreter for a variant of
SNOBOL4, has been developed for use on microcomputer systems. The techniques
for producing an implementation are largely automatic in order to preserve the
integrity and portability of the SPITBOL system. These techniques are discussed
along with a description of an initial implementation on a 65K byte
minicomputer. An interesting theoretical problem which arises when using
procedures which compact the interpretive object code is also analyzed.


title:
The Grothendieck-Teichm\"uller group action on differential forms and
  formality morphism of chains

abstract:
  It is known that one can associate a Kontsevich-type formality morphism to
every Drinfeld associator. We show that this morphism may be extended to a
Kontsevich-Shoikhet formality morphism of cochains and chains, by describing
the action of the Grothendieck-Teichm\"uller group on such objects (up to
homotopy).


title: Mott transitions in three-component Falicov-Kimball model

abstract:
  Metal-insulator transitions are studied within a three-component
Falicov-Kimball model which mimics a mixture of one-component and two-component
fermionic particles with local repulsive interactions in optical lattices.
Within the model the two-component fermionic particles are able to hop in the
lattice, while the one-component fermionic particles are localized. The model
is studied by using the dynamical mean-field theory with exact diagonalization.
Its homogeneous solutions establish Mott transitions for both commensurate and
incommensurate fillings between one third and two thirds. At commensurate one
third and two thirds fillings the Mott transition occurs for any density of
hopping particles, while at incommensurate fillings the Mott transition can
occur only for density one half of hopping particles. At half filling,
depending on the repulsive interactions the reentrant effect of the Mott
insulator is observed. As increasing local interaction of hopping particles,
the first insulator-metal transition is continuous, whereas the second
metal-insulator transition is discontinuous. The second metal-insulator
transition crosses a finite region where both metallic and insulating phase
coexist. At third filling the Mott transition is established only for strong
repulsive interactions. A phase separation occurs together with the phase
transition.


title: Exact BPS bound for noncommutative baby Skyrmions

abstract:
  The noncommutative baby Skyrme model is a Moyal deformation of the
two-dimensional sigma model plus a Skyrme term, with a group-valued or
Grassmannian target. Exact abelian solitonic solutions have been identified
analytically in this model, with a singular commutative limit. Inside any given
Grassmannian, we establish a BPS bound for the energy functional, which is
saturated by these baby Skyrmions. This asserts their stability for unit
charge, as we also test in second-order perturbation theory.


title: Equilibrium Arrival Times to a Queue with Order Penalties

abstract:
  Suppose customers need to choose when to arrive to a congested queue with
some desired service at the end, provided by a single server that operates only
during a certain time interval. We study a model where the customers incur not
only congestion (waiting) costs but also penalties for their index of arrival.
Arriving before other customers is desirable when the value of service
decreases with every admitted customer. This may be the case for example when
arriving at a concert or a bus with unmarked seats or going to lunch in a busy
cafeteria. We provide game theoretic analysis of such queueing systems with a
given number of customers, specifically we characterize the arrival process
which constitutes a symmetric Nash equilibrium.


title:
Pattern formation in individual-based systems with time-varying
  parameters

abstract:
  We study the patterns generated in finite-time sweeps across
symmetry-breaking bifurcations in individual-based models. Similar to the
well-known Kibble-Zurek scenario of defect formation, large-scale patterns are
generated when model parameters are varied slowly, whereas fast sweeps produce
a large number of small domains. The symmetry breaking is triggered by
intrinsic noise, originating from the discrete dynamics at the micro-level.
Based on a linear-noise approximation, we calculate the characteristic length
scale of these patterns. We demonstrate the applicability of this approach in a
simple model of opinion dynamics, a model in evolutionary game theory with a
time-dependent fitness structure, and a model of cell differentiation. Our
theoretical estimates are confirmed in simulations. In further numerical work,
we observe a similar phenomenon when the symmetry-breaking bifurcation is
triggered by population growth.


title: Possible Existence of Charmonium-Nucleus Bound States

abstract:
  Possible existence of $(c\bar{c})-$nucleus bound states are examined. We
adopt Gaussian potentials for the $\eta_{c}-N$ and $J/\psi-N$ interactions. The
relations between the scattering lengths $a$ of $(c\bar{c})-N$ interactions and
the binding energies of $\eta_{c}-NN$, $J/\psi-NN$ and $J/\psi-^{4}$He are
given. The results show that scattering lengths $a \le -0.95$ fm are needed to
make $\eta_{c}-NN$ and $J/\psi-NN$ bound states, while for $a \le -0.24$ fm
there may exist a $J/\psi-^{4}$He bound state.


title:
An Introduction to Hilbert Module Approach to Multivariable Operator
  Theory

abstract:
  Let $\{T_1, \ldots, T_n\}$ be a set of $n$ commuting bounded linear operators
on a Hilbert space $\mathcal{H}$. Then the $n$-tuple $(T_1, \ldots, T_n)$ turns
$\mathcal{H}$ into a module over $\mathbb{C}[z_1, \ldots, z_n]$ in the
following sense: \[\mathbb{C}[z_1, \ldots, z_n] \times \mathcal{H} \raro \clh,
\quad \quad (p, h) \mapsto p(T_1, \ldots, T_n)h,\]where $p \in \mathbb{C}[z_1,
\ldots, z_n]$ and $h \in \mathcal{H}$. The above module is usually called the
Hilbert module over $\mathbb{C}[z_1, \ldots, z_n]$. Hilbert modules over
$\mathbb{C}[z_1, \ldots, z_n]$ (or natural function algebras) were first
introduced by R. G. Douglas and C. Foias in 1976. The two main driving forces
were the algebraic and complex geometric views to multivariable operator
theory.
  This article gives an introduction of Hilbert modules over function algebras
and surveys some recent developments. Here the theory of Hilbert modules is
presented as combination of commutative algebra, complex geometry and the
geometry of Hilbert spaces and its applications to the theory of $n$-tuples ($n
\geq 1$) of commuting operators. The topics which are studied include: model
theory from Hilbert module point of view, Hilbert modules of holomorphic
functions, module tensor products, localizations, dilations, submodules and
quotient modules, free resolutions, curvature and Fredholm Hilbert modules.
More developments in the study of Hilbert module approach to operator theory
can be found in a companion paper, "Applications of Hilbert Module Approach to
Multivariable Operator Theory".


title:
Positive recurrence and transience of a two-station network with server
  states

abstract:
  We study positive recurrence and transience of a two-station network in which
the behavior of the server in each station is governed by a Markov chain with a
finite number of server states; this service process can represent various
service disciplines such as a non-preemptive priority service and K-limited
service. Assuming that exogenous customers arrive according to independent
Markovian arrival processes (MAPs), we represent the behavior of the whole
network as a continuous-time Markov chain and, by the uniformization technique,
obtain the corresponding discrete-time Markov chain, which is positive
recurrent (transient) if and only if the original continuous-time Markov chain
is positive recurrent (resp. transient). This discrete-time Markov chain is a
four-dimensional skip-free Markov modulated reflecting random walk (MMRRW) and,
applying several existing results of MMRRWs to the Markov chain, we obtain
conditions on which the Markov chain is positive recurrent and on which it is
transient. The conditions are represented in terms of the difference of the
input rate and output rate of each queue in each induced Markov chain. In order
to demonstrate how our results work in two-station networks, we give several
examples.


title: On the algebraic unknotting number

abstract:
  The algebraic unknotting number u_a(K) of a knot K was introduced by Hitoshi
Murakami. It equals the minimal number of crossing changes needed to turn K
into an Alexander polynomial one knot. In a previous paper the authors used the
Blanchfield form of a knot K to define an invariant n(K) and proved that n(K)
is a lower bound on u_a(K). They also showed that n(K) subsumes all previous
classical lower bounds on the (algebraic) unknotting number. In this paper we
prove that n(K)=u_a(K).


title: Multi-Scalar-Tensor Equivalents for Modified Gravitational Actions

abstract:
  A general scheme of constructing scalar-tensor equivalents to modified
gravitational actions are studied using the algebra of exterior differential
forms and the first order formalism that allows an independent connection and
coframe. By introducing appropriate constraints on the connection,
pseudo-Riemannian cases as well as non-Riemannian cases are discussed for
various gravitational models. The issue of the dynamical degree of freedom for
the resulting scalar fields is discussed at the level of the field equations.
Explicit scalar-tensor equivalents for gravitational models based on $f(R)$
models, the quadratic curvature lagrangians and the models involving the
gradients of the scalar curvature are presented. In particular, explicit ST
equivalence for gravitational lagrangians popular in some cosmological models
are constructed.


title: Intermittent Kalman Filtering: Eigenvalue Cycles and Nonuniform Sampling

abstract:
  We consider Kalman filtering problems when the observations are
intermittently erased or lost. It was known that the estimates are mean-square
unstable when the erasure probability is larger than a certain critical value,
and stable otherwise. But the characterization of the critical erasure
probability has been open for years. We introduce a new concept of
\textit{eigenvalue cycles} which captures periodicity of systems, and
characterize the critical erasure probability based on this. It is also proved
that eigenvalue cycles can be easily broken if the original physical system is
considered to be continuous-time --- randomly-dithered nonuniform sampling of
the observations makes the critical erasure probability almost surely
$\frac{1}{|\lambda_{max}|^2}$.


title: Majorana states in helical Shiba chains and ladders

abstract:
  Motivated by recent proposals to realize Majorana bound states in chains and
arrays of magnetic atoms deposited on top of a superconductor, we study the
topological properties of various chain structures, ladders and two-dimensional
arrangements exhibiting magnetic helices. We show that magnetic domain walls
where the chirality of a magnetic helix is inverted support two protected
Majorana states giving rise to a tunneling conductance peak twice the height of
a single Majorana state. The topological properties of coupled chains exhibit
nontrivial behaviour as a function of the number of chains beyond the even-odd
dichotomy expected from the simple $\mathbb{Z}_2$ nature of coupled Majorana
states. In addition, it is possible that a ladder of two or more coupled chains
exhibit Majorana edge states even when decoupled chains are trivial. We
formulate a general criterion for the number of Majorana edge states in
multichain ladders and discuss some experimental consequences of our findings.


title: Tsallis entropy and hyperbolicity

abstract:
  Some preliminary evidence suggests the conjecture that the collective
behaviour of systems having long-range interactions may be described more
effectively by the Tsallis rather than by the Boltzmann/Gibbs/Shannon entropy.
To this end, we examine consequences of the biggest difference between these
two entropies: their composition properties. We rely on a metric formalism that
establishes the "hyperbolic" nature of Tsallis entropy and explore some of its
consequences for the underlying systems. We present some recent and some
forthcoming results of our work


title:
Modified equipartition calculation for supernova remnants. Cases \alpha
  =0.5 and \alpha =1

abstract:
  The equipartition or minimum-energy calculation is a well-known procedure for
estimating magnetic field strength and total energy in the magnetic field and
cosmic ray particles by using only the radio synchrotron emission. In one of
our previous papers we have offered a modified equipartition calculation for
supernova remnants (SNRs) with spectral indices 0.5<\alpha <1. Here we extend
the analysis to SNRs with \alpha =0.5 and \alpha =1.


title:
Finer filtration for matrix-valued cocycle based on Oseledec's
  multiplicative ergodic theorem

abstract: In this paper, we improve the classical multiplicative ergodic theorem.


title:
Large scale IRAM 30m CO-observations in the giant molecular cloud
  complex W43

abstract:
  We aim to give a full description of the distribution and location of dense
molecular clouds in the giant molecular cloud complex W43. It has previously
been identified as one of the most massive star-forming regions in our Galaxy.
To trace the moderately dense molecular clouds in the W43 region, we initiated
an IRAM 30m large program, named W43-HERO, covering a large dynamic range of
scales (from 0.3 to 140 pc). We obtained on-the-fly-maps in 13CO (2-1) and C18O
(2-1) with a high spectral resolution of 0.1 km/s and a spatial resolution of
12". These maps cover an area of ~1.5 square degrees and include the two main
clouds of W43, as well as the lower density gas surrounding them. A comparison
with Galactic models and previous distance calculations confirms the location
of W43 near the tangential point of the Scutum arm at a distance from the Sun
of approximately 6 kpc. The resulting intensity cubes of the observed region
are separated into sub-cubes, centered on single clouds which are then analyzed
in detail. The optical depth, excitation temperature, and H2 column density
maps are derived out of the 13CO and C18O data. These results are then compared
with those derived from Herschel dust maps. The mass of a typical cloud is
several 10^4 solar masses while the total mass in the dense molecular gas (>100
cm^-3) in W43 is found to be about 1.9e6 solar masses. Probability distribution
functions obtained from column density maps derived from molecular line data
and Herschel imaging show a log-normal distribution for low column densities
and a power-law tail for high densities. A flatter slope for the molecular line
data PDF may imply that those selectively show the gravitationally collapsing
gas.


title:
Strong electronic correlations in iron pnictides: Comparison of the
  optical spectra for BaFe2As2-related compounds

abstract:
  We carried out combined transport and optical measurements for BaFe2As2 and
five isostructural transition-metal (TM) pnictides. The low-energy optical
conductivity spectra of these compounds are, to a good approximation,
decomposed into a narrow Drude (coherent) component and an incoherent
component. The iron arsenides, BaFe2As2 and KFe2As2, are distinct from other
pnictides in their highly incoherent charge dynamics or bad metallic behavior
with the coherent Drude component occupying a tiny fraction of the low-energy
spectral weight. The fraction of the coherent spectral weight or the degree of
coherence is shown to be well correlated with the TM-pnictogen bond angle and
the electron filling of TM 3d orbitals, which are measures of the strength of
electronic correlations. The iron arsenides are thus strongly correlated
systems, and the doping into BaFe2As2 controls the strength of electronic
correlations. This naturally explains a remarkable asymmetry in the charge
dynamics of electron- and hole-doped systems, and the unconventional
superconductivity appears to emerge when the correlations are fairly strong.


title: Light-Cone Distribution Amplitudes for Heavy-Quark Hadrons

abstract:
  We construct parametrizations of light-cone distribution amplitudes (LCDAs)
for B-mesons and Lambda_b-baryons that obey various theoretical constraints,
and which are simple to use in factorization theorems relevant for
phenomenological applications in heavy-flavour physics. In particular, we find
the eigenfunctions of the Lange-Neubert renormalization kernel, which allow for
a systematic implementation of renormalization-group evolution effects for both
B-meson and \Lambda_b-baryon decays. We also present a new strategy to
construct LCDA models from momentum-space projectors, which can be used to
implement Wandzura-Wilczek--like relations, and which allow for a comparison
with theoretical approaches that go beyond the collinear limit for the
light-quark momenta in energetic heavy-hadron decays.


title: The chiral magnetic nanomotors

abstract:
  Propulsion of the chiral magnetic nanomotors powered by a rotating magnetic
field is in the focus of the modern biomedical applications. This technology
relies on strong interaction of dynamic and magnetic degrees of freedom of the
system. Here we study in detail various experimentally observed regimes of the
helical nanomotor orientation and propulsion depending on the actuation
frequency, and establish the relation of these two properties with remanent
magnetization and geometry of the helical nanomotors. The theoretical
predictions for the transition between the regimes and nanomotor orientation
and propulsion speed are in excellent agreement with available experimental
data. The proposed theory offers a few simple guidelines towards the optimal
design of the magnetic nanomotors. In particular, efficient nanomotors should
be fabricated of hard magnetics, e.g., cobalt, magnetized transversally and
have the geometry of a normal helix with a helical angle of 35-45 degrees.


title: Polyynyl-substituted PAH molecules and DIB carriers

abstract:
  Polycyclic aromatic hydrocarbon (PAH) molecules have been long considered
promising candidates for the carriers of the diffuse interstellar bands (DIBs).
The PAH-DIB hypothesis, however, raises two major issues. First, the number of
interstellar PAH species is potentially orders of magnitude larger than the
number of DIBs. Second, the absorption spectrum of a PAH is in general
dominated by bands found at UV wavelengths while, conversely, DIBs are absent
from the UV wavelength domain and arise at visible and near IR wavelengths.
These issues do not necessarily weaken the PAH-DIB hypothesis and can actually
allow us to refine it. In that context, we analyze the UV/vis absorption
spectra of PAH molecules isolated in Ne matrices and propose that
polyynyl-substituted PAHs, or similar species, are valid candidates for the
carriers of the DIBs. Finally, a possible lifecycle for DIB-carrying PAHs is
presented.


title:
Derivations with values in quasi-normed bimodules of locally measurable
  operators

abstract:
  We prove that every derivation acting on a von Neumann algebra $\mathcal{M}$
with values in a quasi-normed bimodule of locally measurable operators
affiliated with $\mathcal{M}$ is necessarily inner.


title:
Using tf-idf as an edge weighting scheme in user-object bipartite
  networks

abstract:
  Bipartite user-object networks are becoming increasingly popular in
representing user interaction data in a web or e-commerce environment. They
have certain characteristics and challenges that differentiates them from other
bipartite networks. This paper analyzes the properties of five real world
user-object networks. In all cases we found a heavy tail object degree
distribution with popular objects connecting together a large part of the users
causing significant edge inflation in the projected users network. We propose a
novel edge weighting strategy based on tf-idf and show that the new scheme
improves both the density and the quality of the community structure in the
projections. The improvement is also noticed when comparing to partially random
networks.


title: Nijenhuis forms on $L_\infty$-algebras and Poisson geometry

abstract:
  We investigate Nijenhuis deformations of $L_\infty$-algebras, a notion that
unifies several Nijenhuis deformations, namely those of Lie algebras, Lie
algebroids, Poisson structures and Courant structures. Additional examples,
linked to Lie $n$-algebras and $n$-plectic manifolds, are included.


title:
Can we still benefit from international diversification? The case of the
  Czech and German stock markets

abstract:
  One of the findings of the recent literature is that the 2008 financial
crisis caused reduction in international diversification benefits. To fully
understand the possible potential from diversification, we build an empirical
model which combines generalised autoregressive score copula functions with
high frequency data, and allows us to capture and forecast the conditional
time-varying joint distribution of stock returns. Using this novel methodology
and fresh data covering five years after the crisis, we compute the conditional
diversification benefits to answer the question, whether it is still
interesting for an international investor to diversify. As diversification
tools, we consider the Czech PX and the German DAX broad stock indices, and we
find that the diversification benefits strongly vary over the 2008--2013 crisis
years.


title:
A new equation of state for neutron star matter with nuclei in the crust
  and hyperons in the core

abstract:
  The equation of state for neutron stars in a wide-density range at zero
temperature is constructed. The chiral quark-meson coupling model within
relativistic Hartree-Fock approximation is adopted for uniform nuclear matter.
The coupling constants are determined so as to reproduce the experimental data
of atomic nuclei and hypernuclei. In the crust region, nuclei are taken into
account within the Thomas-Fermi calculation. All octet baryons are considered
in the core region, while only $\Xi^{-}$ appears in neutron stars. The
resultant maximum mass of neutron stars is $1.95M_\odot$, which is consistent
with the constraint from the recently observed massive pulsar, PSR J1614-2230.


title:
Computing Adapted Bases for Conformal Automorphism Groups of Riemann
  Surfaces

abstract:
  The concept of an adapted homology basis for a prime order conformal
automorphism of a compact Riemann surface extends to arbitrary finite groups of
conformal automorphisms. Here we compute some examples of adapted homology
bases for some groups of automorphisms. The method is to begin by apply the
Schreier-Reidemeister rewriting process along with the Schreier-Reidemeister
Theorem and then to eliminate generators and relations until there is one
single large defining relation for the fundamental group in which every
generator and its inverse occurs. We are then able to compute the action of the
group on the homology image of these generators in the first homology group.
The matrix of the action is in a simple form. This has applications to the
representation variety.


title: Warped Poisson Brackets on Warped Products

abstract:
  In this paper, we generalize the geometry of the product pseudo-Riemannian
manifold equipped with the product Poisson structure (\cite{Nas2}) to the
geometry of a warped product of pseudo-Riemannian manifolds equipped with a
warped Poisson structure. We construct three bivector fields on a product
manifold and show that each of them lead under certain conditions to a Poisson
structure. One of these bivector fields will be called the warped bivector
field. For a warped product of pseudo-Riemannian manifolds equipped with a
warped bivector field, we compute the corresponding contravariant Levi-Civita
connection and the curvatures associated with.


title:
Large deviations of the dynamical activity in the East model: analysing
  structure in biased trajectories

abstract:
  We consider large deviations of the dynamical activity in the East model. We
bias this system to larger than average activity and investigate the structure
that emerges. To best characterise this structure, we exploit the fact that
there are effective interactions that would reproduce the same behaviour in an
equilibrium system. We combine numerical results with linear response theory
and variational estimates of these effective interactions, giving the first
insights into such interactions in a many-body system, across a wide range of
biases. The system exhibits a hierarchy of responses to the bias, remaining
quasi-equilibrated on short length scales, but deviating far from equilibrium
on large length scales. We discuss the connection between this hierarchy and
the hierarchical aging behaviour of the system.


title:
Metropolis-Hastings thermal state sampling for numerical simulations of
  Bose-Einstein condensates

abstract:
  We demonstrate the application of the Metropolis-Hastings algorithm to
sampling of classical thermal states of one-dimensional Bose-Einstein
quasicondensates in the classical fields approximation, both in untrapped and
harmonically trapped case. The presented algorithm can be easily generalized to
higher dimensions and arbitrary trap geometry. For truncated Wigner simulations
the quantum noise can be added with conventional methods (half a quantum of
energy in every mode). The advantage of the presented method over the usual
analytical and stochastic ones lies in its ability to sample not only from
canonical and grand canonical distributions, but also from the generalized
Gibbs ensemble, which can help to shed new light on thermodynamics of
integrable systems.


title: Discontinuities in the Maximum-Entropy Inference

abstract:
  We revisit the maximum-entropy inference of the state of a finite-level
quantum system under linear constraints. The constraints are specified by the
expected values of a set of fixed observables. We point out the existence of
discontinuities in this inference method. This is a pure quantum phenomenon
since the maximum-entropy inference is continuous for mutually commuting
observables. The question arises why some sets of observables are distinguished
by a discontinuity in an inference method which is still discussed as a
universal inference method. In this paper we make an example of a discontinuity
and we explain a characterization of the discontinuities in terms of the
openness of the (restricted) linear map that assigns expected values to states.


title:
Optimal average approximations for functions mapping in quasi-Banach
  spaces

abstract:
  In 1994, M. M. Popov [On integrability in F-spaces, Studia Math. no 3,
205-220] showed that the fundamental theorem of calculus fails, in general, for
functions mapping from a compact interval of the real line into the lp-spaces
for 0<p<1, and the question arose whether such a significant result might hold
in some non-Banach spaces. In this article we completely settle the problem by
proving that the fundamental theorem of calculus breaks down in the context of
any non-locally convex quasi-Banach space. Our approach introduces the tool of
Riemann-integral averages of continuous functions, and uses it to bring out to
light the differences in behavior of their approximates in the lack of local
convexity. As a by-product of our work we solve a problem raised in [F. Albiac
and J.L. Ansorena, Lipschitz maps and primitives for continuous functions in
quasi-Banach space, Nonlinear Anal. 75 (2012), no. 16, 6108-6119] on the
different types of spaces of differentiable functions with values on a
quasi-Banach space.


title:
Quantum control with noisy fields: computational complexity vs.
  sensitivity to noise

abstract:
  A closed quantum system is defined as completely controllable if an arbitrary
unitary transformation can be executed using the available controls. In
practice, control fields are a source of unavoidable noise, which has to be
suppressed to retain controllability. Can one design control fields such that
the effect of noise is negligible on the time-scale of the transformation? This
question is intimately related to the fundamental problem of a connection
between the computational complexity of the control problem and the sensitivity
of the controlled system to noise. The present study considers a paradigm of
control, where the Lie-algebraic structure of the control Hamiltonian is fixed,
while the size of the system increases with the dimension of the Hilbert space
representation of the algebra. We find two types of control tasks, easy and
hard. Easy tasks are characterized by a small variance of the evolving state
with respect to the operators of the control operators. They are relatively
immune to noise and the control field is easy to find. Hard tasks have a large
variance, are sensitive to noise and the control field is hard to find. The
influence of noise increases with the size of the system, which is measured by
the scaling factor $N$ of the largest weight of the representation. For fixed
time and control field as O(N) for easy tasks and as $O(N^2)$ for hard tasks.
As a consequence, even in the most favorable estimate, for large quantum
systems, generic noise in the controls dominates for a typical class of target
transformations, i.e., complete controllability is destroyed by noise.


title: Dimension free Harnack inequalities on $\RCD(K, \infty)$ spaces

abstract:
  The dimension free Harnack inequality for the heat semigroup is established
on the $\RCD(K,\infty)$ space, which is a non-smooth metric measure space
having the Ricci curvature bounded from below in the sense of
Lott-Sturm-Villani plus the Cheeger energy being quadratic. As its
applications, the heat semigroup entropy-cost inequality and contractivity
properties of the semigroup are studied, and a strong enough Gaussian
concentration implying the log-Sobolev inequality is also shown as a
generalization of the one on the smooth Riemannian manifold.


title:
The Herschel Virgo Cluster Survey XIV: transition-type dwarf galaxies in
  the Virgo cluster

abstract:
  We use dust scaling relations to investigate the hypothesis that Virgo
cluster transition-type dwarfs are infalling star-forming field galaxies, which
is argued based on their optical features (e.g. disks, spiral arms, bars) and
kinematic properties similar to late-type galaxies. After their infall,
environmental effects gradually transform them into early-type galaxies through
the removal of their interstellar medium and quenching of all star formation
activity. In this paper, we aim to verify whether this hypothesis holds using
far-infrared diagnostics based on Herschel observations of the Virgo cluster
taken as part of the Herschel Virgo Cluster Survey (HeViCS). We select
transition-type objects in the nearest cluster, Virgo, based on spectral
diagnostics indicative for their residual or ongoing star formation. We detect
dust Md ~ 10^{5-6} Msun in 36% of the transition-type dwarfs located on the
high end of the stellar mass distribution. This suggests that the dust
reservoirs present in non-detections fall just below the Herschel detection
limit (< 1.1x10^5 Msun). Dust scaling relations support the hypothesis of a
transformation between infalling late-type galaxies to quiescent low-mass
spheroids governed by environmental effects, with dust-to-stellar mass
fractions for transition-type dwarfs in between values characteristic for
late-type objects and the lower dust fractions observed in early-type galaxies.
Several transition-type dwarfs demonstrate blue central cores, hinting at the
radially outside-in removal of gas and quenching of star formation activity.
The fact that dust is also confined to the inner regions suggests that metals
are stripped in the outer regions along with the gas. In the scenario of most
dust being stripped from the galaxy along with the gas, we argue that...
(abridged)


title:
Heat kernel upper bounds under the generalized curvature(-dimension)
  inequality

abstract:
  In the sub-Riemannian manifolds, on the one hand, following Baudoin-Garofalo
\cite{BaudoinGarofalo}, the upper bound for heat kernels associated to a class
of locally subelliptic operators are given under the generalized
curvature-dimension inequality with a negative curvature parameter; on the
other hand, the argument combining Grigor'yan's integrated maximum principle
with Wang's dimension-free Harnack inequality is also shown to derive the upper
bound for the heat kernel under the generalized curvature inequality.


title:
Nonlinear dynamics of plasma oscillations modeled by a forced modified
  Van der Pol-Duffing oscillator

abstract:
  This paper considers nonlinear dynamics of plasma oscillations modeled by a
forced modified Van der Pol-Duffing oscillator. These plasma oscillations are
described by a nonlinear differential equation of the form $ \ddot{x}+ \epsilon
(1 +{x}^{2}){\dot{x}} + x+ \alpha \epsilon{x}{\dot{x}} + {\beta}x^{2}+\gamma
x^{3}= F\cos{\Omega t}.$ The amplitudes of the forced harmonic, superharmonic
and subharmonic oscillatory states are obtained using the harmonic balance
technique and the multiple time scales methods. Bifurcation sequences displayed
by the model for each type of oscillatory states are performed numerically
through the fourth order Runge- Kutta scheme. The influences of the differents
parameters and of amplitude of external forced have been found.


title:
Normal-state charge dynamics in doped BaFe2As2: Roles of doping and
  necessary ingredients for superconductivity

abstract:
  We carried out a comparative study of the in-plane resistivity and optical
spectrum of doped BaFe2As2 and investigated the doping evolution of the charge
dynamics. For BaFe2As2, charge dynamics is incoherent at high temperatures.
Electron (Co) and isovalent (P) doping into BaFe2As2 increase coherence of the
system and transform the incoherent charge dynamics into highly coherent one.
On the other hand, charge dynamics remains incoherent for hole (K) doping. It
is found in common with any type of doping that superconductivity with high
transition temperature emerges when the normal-state charge dynamics maintains
incoherence and when the resistivity associated with the coherent channel
exhibits dominant temperature-linear dependence.


title: Operator scaled Wiener bridges

abstract:
  We introduce operator scaled Wiener bridges by incorporating a matrix scaling
in the drift part of the SDE of a multidimensional Wiener bridge. A sufficient
condition for the bridge property of the SDE solution is derived in terms of
the eigenvalues of the scaling matrix. We analyze the asymptotic behavior of
the bridges and briefly discuss the question whether the scaling matrix
determines uniquely the law of the corresponding bridge.


title:
Detuning-dependent narrowing of Mollow triplet lines of driven quantum
  dots

abstract:
  We study the two-time correlation function and the resonance fluorescence
spectrum of a semiconductor quantum dot excited by a strong off-resonant laser
pulse. The obtained analytical expressions exhibit a specific
detuning-dependent damping of Rabi oscillations of the dressed quantum dot as
well as a detuning-dependent width of Mollow-triplet lines. In the absence of
pure dephasing, the central peak of the triplet is broadened, upon increasing
detuning, but the blue and red side peaks are narrowed. We demonstrate that
pure dephasing processes can invert these dependences. A crossover between the
regimes of detuning-dependent narrowing and broadening of the side and central
peaks is identified. The predicted effects are consistent with resent
experimental results and numerical calculations.


title: Shearless transport barriers in unsteady two-dimensional flows and maps

abstract:
  We develop a variational principle that extends the notion of a shearless
transport barrier from steady to general unsteady two-dimensional flows and
maps defined over a finite time interval. This principle reveals that
hyperbolic Lagrangian Coherent Structures (LCSs) and parabolic LCSs (or jet
cores) are the two main types of shearless barriers in unsteady flows. Based on
the boundary conditions they satisfy, parabolic barriers are found to be more
observable and robust than hyperbolic barriers, confirming widespread numerical
observations. Both types of barriers are special null-geodesics of an
appropriate Lorentzian metric derived from the Cauchy--Green strain tensor.
Using this fact, we devise an algorithm for the automated computation of
parabolic barriers. We illustrate our detection method on steady and unsteady
non-twist maps and on the aperiodically forced Bickley jet.

categories: math.DS nlin.CD physics.flu-dyn physics.geo-ph physics.plasm-ph


title: Minimal crystallizations of 3-manifolds

abstract:
  We have introduced the weight of a group which has a presentation with number
of relations is at most the number of generators. We have shown that the number
of facets of any contracted pseudotriangulation of a connected closed
3-manifold $M$ is at least the weight of $\pi(M, \ast)$. This lower bound is
sharp for the 3-manifolds $\mathbb{R P}^3$, $L(3,1)$, $L(5,2)$, $S^1\times S^1
\times S^1$, $S^2 \times S^1$, $S^2 \mbox{$\times \hspace{-2.8mm}_{-}$} S^1$
and $S^3/Q_8$, where $Q_8$ is the quaternion group. Moreover, there is a unique
such facet minimal pseudotriangulation in each of these seven cases. We have
also constructed contracted pseudotriangulations of $L(kq-1,q)$ with $4(q+k-1)$
facets for $q \geq 3$, $k \geq 2$ and $L(kq+1,q)$ with $4(q+k)$ facets for
$q\geq 4$, $k\geq 1$. By a recent result of Swartz, our pseudotriangulations of
$L(kq+1, q)$ are facet minimal when $kq+1$ are even. In 1979, Gagliardi found
presentations of the fundamental group of a manifold $M$ in terms of a
contracted pseudotriangulation of $M$. Our construction is the converse of
this, namely, given a presentation of the fundamental group of a 3-manifold
$M$, we construct a contracted pseudotriangulation of $M$. So, our construction
of a contracted pseudotriangulation of a 3-manifold $M$ is based on a
presentation of the fundamental group of $M$ and it is computer-free.


title: DISCO: Distributed Multi-domain SDN Controllers

abstract:
  Modern multi-domain networks now span over datacenter networks, enterprise
networks, customer sites and mobile entities. Such networks are critical and,
thus, must be resilient, scalable and easily extensible. The emergence of
Software-Defined Networking (SDN) protocols, which enables to decouple the data
plane from the control plane and dynamically program the network, opens up new
ways to architect such networks. In this paper, we propose DISCO, an open and
extensible DIstributed SDN COntrol plane able to cope with the distributed and
heterogeneous nature of modern overlay networks and wide area networks. DISCO
controllers manage their own network domain and communicate with each others to
provide end-to-end network services. This communication is based on a unique
lightweight and highly manageable control channel used by agents to
self-adaptively share aggregated network-wide information. We implemented DISCO
on top of the Floodlight OpenFlow controller and the AMQP protocol. We
demonstrated how DISCO's control plane dynamically adapts to heterogeneous
network topologies while being resilient enough to survive to disruptions and
attacks and providing classic functionalities such as end-point migration and
network-wide traffic engineering. The experimentation results we present are
organized around three use cases: inter-domain topology disruption, end-to-end
priority service request and virtual machine migration.


title: On the structure of self-complementary graphs

abstract:
  A \emph{self-complementary} graph is a graph isomorphic to its complement. An
isomorphism between $G$ and its complement, viewed as a permutation of $V(G)$,
is then called an \emph{antimorphism}. A \emph{skew partition} of $G$ is a
partition of $V(G)$ into 4 sets $A,B,C,D$ such that there is no edge between
$A,B$ and every possible edge between $C,D$. A \emph{symmetric partition} of
$G$ is a partition of $V(G)$ into 4 sets $A,B,C,D$ such that there is no edge
between $A, D$, no edge between $B, C$, every possible edge between $A,B$ and
every possible edge between $C,D$.
  We give a new proof of a theorem of Gibbs saying that every
self-complementary graph on $4k$ vertices has $k$ disjoint paths on 4 vertices
as induced subgraph. This new proof gives more structural information than the
original one. We conjecture that every self-complementary graph on $4k$
vertices either has an induced cycle on 5 vertices, or a skew partition, or a
symmetric partition. The new proof of Gibb's theorem yields a proof of the
conjecture for the self-complementary graphs that have an antimorphism that is
the product of a two circular permutations, one of them of length 4.


title:
Inference Methods for Interaction and Noise Intensities Using Only
  Spike-time Data on Coupled Oscillators

abstract:
  We propose theoretical methods to infer coupling strength and noise intensity
simultaneously through an observation of spike timing in two well-synchronized
noisy oscillators. A phase oscillator model is applied to derive formulae
relating each of the parameters to some statistics from spike-time data. Using
these formulae, each parameter is inferred from a specific set of statistics.
We demonstrate the methods with the FitzHugh-Nagumo model as well as the phase
model. Our methods do not require any external perturbation and thus are ready
for application to various experimental systems.


title:
A generalized closure concept based on neighborhood-equivalence and
  preserving graph Hamiltonicity

abstract:
  A graph is Hamiltonian if it contains a cycle which goes through all vertices
exactly once. Determining if a graph is Hamiltonian is known as a NP-complete
problem and no satisfactory characterization for these graphs has been found.
  In 1976 Bondy and Chvatal introduced a way to get round the Hamiltonicity
problem complexity by using a closure of the graph. This closure is a
supergraph of G which preserves Hamiltonicity, that is, which is Hamiltonian if
and only if G is. Since this seminal work, several closure concepts preserving
Hamiltonicity were introduced. In particular Ryjacek defined in 1997 a closure
concept for claw-free graphs based on local completion. The completion is
performed for every eligible vertex of the graph.
  Extending these works, Vallee and Bretto recently introduced a new closure
concept preserving Hamiltonicity and based on local completion. The local
completion is performed for each neighborhood-equivalence eligible vertex of
the graph.
  In this article, we generalize the main results of Vallee and Bretto by
introducing a broader notion of neighborhood equivalence eligibility, allowing
the definition of a denser graph closure which still preserves Hamiltonicity.


title: Viable f(T) models are practically indistinguishable from LCDM

abstract:
  We investigate the cosmological predictions of several $f(T)$ models, with up
to two parameters, at both the background and the perturbation levels. Using
current cosmological observations (geometric supernovae type Ia, cosmic
microwave background and baryonic acoustic oscillation and dynamical growth
data) we impose constraints on the distortion parameter, which quantifies the
deviation of these models from the concordance $\Lambda$ cosmology at the
background level. In addition we constrain the growth index $\gamma$ predicted
in the context of these models using the latest perturbation growth data in the
context of three parametrizations for $\gamma$. The evolution of the best fit
effective Newton constant, which incorporates the $f(T)$-gravity effects, is
also obtained along with the corresponding $1\sigma$ error regions. We show
that all the viable parameter sectors of the $f(T)$ gravity models considered
practically reduce these models to $\Lambda$CDM. Thus, the degrees of freedom
that open up to $\Lambda$CDM in the context of $f(T)$ gravity models are not
utilized by the cosmological data leading to an overall disfavor of these
models.


title:
On the automorphisms group of the asymptotic pants complex of an
  infinite surface of genus zero

abstract:
  The braided Thompson group $\mathcal B$ is an asymptotic mapping class group
of a sphere punctured along the standard Cantor set, endowed with a rigid
structure. Inspired from the case of finite type surfaces we consider a
Hatcher-Thurston cell complex whose vertices are asymptotically trivial pants
decompositions. We prove that the automorphism group $\hat{\mathcal
B^{\frac{1}{2}}}$ of this complex is also an asymptotic mapping class group in
a weaker sense. Moreover $\hat{\mathcal B^{\frac{1}{2}}}$ is obtained by
$\mathcal B$ by first adding new elements called half-twists and further
completing it.


title: Around the Carnot theorem

abstract:
  We study the Carnot theorem and the configuration of points and lines in
connection with it. It is proven that certain significant points in the
configuration lie on the same lines and same conics. The proof of an equivalent
statement formulated by Bradley is given. An open conjecture, established by
Bradley, is proved using the theorems of Carnot and Menelaus.


title: ELB-Trees, An Efficient and Lock-free B-tree Derivative

abstract:
  This technical report is an extension of the paper of the same title, which
is to appear at MUCOCOS'13. The technical report proves correctness of the
ELB-trees operations' semantics and that the operations are lock-free.


title:
Theoretical predictions for the effect of nebular emission on the broad
  band photometry of high-redshift galaxies

abstract:
  By combining optical and near-IR observations from the Hubble Space Telescope
with NIR photometry from the Spitzer Space Telescope it is possible to measure
the rest-frame UV-optical colours of galaxies at z=4-8. The UV-optical spectral
energy distribution of star formation dominated galaxies is the result of
several different factors. These include the joint distribution of stellar
masses, ages, and metallicities, and the subsequent reprocessing by dust and
gas in the ISM. Using a large cosmological hydrodynamical simulation we
investigate the predicted spectral energy distributions of galaxies at
high-redshift with a particular emphasis on assessing the potential
contribution of nebular emission. We find that the average pure stellar
UV-optical colour correlates with both luminosity and redshift such that
galaxies at lower-redshift and higher-luminosity are typically redder. Assuming
the escape fraction of ionising photons is close to zero, the effect of nebular
emission is to redden the UV-optical 1500-V_w colour by, on average, 0.4 mag at
z=8 declining to 0.25 mag at z=4. Young and low-metallicity stellar
populations, which typically have bluer pure stellar UV-optical colours,
produce larger ionising luminosities and are thus more strongly affected by the
reddening effects of nebular emission. This causes the distribution of 1500-V_w
colours to narrow and the trends with luminosity and redshift to weaken. The
strong effect of nebular emission leaves observed-frame colours critically
sensitive to the source redshift. For example, increasing the redshift by 0.1
can result in observed frame colours changing by up to ~0.6. These predictions
reinforce the need to include nebular emission when modelling the spectral
energy distributions of galaxies at high-redshift and also highlight the
difficultly in interpreting the observed colours of individual galaxies without
precise redshifts.


title:
Momentum relaxation of a mobile impurity in a one-dimensional quantum
  gas

abstract:
  We investigate the time evolution of the momentum of an impurity atom
injected into a degenerate Tonks-Girardeau gas. We establish that given an
initial momentum $p_0$ the impurity relaxes to a steady state with a
non-vanishing momentum $p_\infty.$ The nature of the steady state is found to
depend drastically on whether the masses of the impurity and the host are equal
or not. This is due to multiple coherent scattering processes leading to a
resonant interaction between the impurity and the host in the case of equal
masses. The dependence of $p_\infty$ on $p_0$ remains non-trivial even in the
limit of vanishing interaction between the impurity and host particles. In this
limit $p_\infty(p_0)$ is found explicitly.


title:
Detrended Cross-Correlation Analysis Consistently Extended to
  Multifractality

abstract:
  We propose a novel algorithm - Multifractal Cross-Correlation Analysis
(MFCCA) - that constitutes a consistent extension of the Detrended
Cross-Correlation Analysis (DCCA) and is able to properly identify and quantify
subtle characteristics of multifractal cross-correlations between two time
series. Our motivation for introducing this algorithm is that the already
existing methods like MF-DXA have at best serious limitations for most of the
signals describing complex natural processes and often indicate multifractal
cross-correlations when there are none. The principal component of the present
extension is proper incorporation of the sign of fluctuations to their
generalized moments. Furthermore, we present a broad analysis of the model
fractal stochastic processes as well as of the real-world signals and show that
MFCCA is a robust and selective tool at the same time, and therefore allows for
a reliable quantification of the cross-correlative structure of analyzed
processes. In particular, it allows one to identify the boundaries of the
multifractal scaling and to analyze a relation between the generalized Hurst
exponent and the multifractal scaling parameter $\lambda_q$. This relation
provides information about character of potential multifractality in
cross-correlations and thus enables a deeper insight into dynamics of the
analyzed processes than allowed by any other related method available so far.
By using examples of time series from stock market, we show that financial
fluctuations typically cross-correlate multifractally only for relatively large
fluctuations, whereas small fluctuations remain mutually independent even at
maximum of such cross-correlations. Finally, we indicate possible utility of
MFCCA to study effects of the time-lagged cross-correlations.


title: The Extreme Right Filter Bubble

abstract:
  Due to its status as the most popular video sharing platform, YouTube plays
an important role in the online strategy of extreme right groups, where it is
often used to host associated content such as music and other propaganda. In
this paper, we develop a categorization suitable for the analysis of extreme
right channels found on YouTube. By combining this with an NMF-based topic
modelling method, we categorize channels originating from links propagated by
extreme right Twitter accounts. This method is also used to categorize related
channels, which are determined using results returned by YouTube's related
video service. We identify the existence of a "filter bubble", whereby users
who access an extreme right YouTube video are highly likely to be recommended
further extreme right content.


title: Spectroscopy of a topological phase

abstract:
  Dynamical correlation functions of the toric code in a uniform magnetic field
are studied inside the topological phase, in the small-field limit. Such an
experimentally measurable quantity displays rich field-dependent features that
can be understood via the interplay of the kinetics and the interaction of the
anyonic excitations. In particular, it is sensitive to the two-quasiparticle
bound states that are present in the spectrum for a wide range of magnetic
fields. Interestingly, such collective modes can even constitute the
lowest-energy excitations of the system.


title:
The modellers' encounter with ecological theory. Or, what is this thing
  called `growth rate'?

abstract:
  The attempt to determine the population growth rate from field data reveals
several ambiguities in its definition(s), which seem to throw into question the
very concept itself. However, an alternative point of view is proposed that not
only preserves the identity of the concept, but also helps discriminate between
competing models for capturing the data.


title: First studies with the Resistive-Plate WELL gaseous multiplier

abstract:
  We present the results of first studies of the Resistive Plate WELL (RPWELL):
a single-faced THGEM coupled to a copper anode via a resistive layer of high
bulk resistivity. We explored various materials of different bulk resistivity
(10^9 - 10^12 Ohm cm) and thickness (0.4 - 4 mm). Our most successful
prototype, with a 0.6 mm resistive plate of ~10^9 Ohm cm, achieved gains of up
to 10^5 with 8 keV x-ray in Ne/5%CH4; a minor 30% gain drop occurred with a
rate increase from 10 to 10^4 Hz/mm^2. The detector displayed a full
"discharge-free" operation--even when exposed to high primary ionization
events. We present the RPWELL detector concept and compare its performance to
that of other previously explored THGEM configurations--in terms of gain, its
curves, dependence on rate, and the response to high ionization. The robust
Resistive Plate WELL concept is a step forward in the Micro-Pattern
Gas-Detector family, with numerous potential applications.


title:
Simple non-empirical procedure for spin-component-scaled MP2 methods
  applied to the calculation of dissociation energy curve of
  noncovalently-interacting systems

abstract:
  We present a simple and non-empirical method to determine optimal scaling
coefficients, within the (spin-component)-scaled MP2 approach, for calculating
intermolecular potential energies of noncovalently-interacting systems. The
method is based on an observed proportionality between (spin-component) MP2 and
CCSD(T) energies for a wide range of intermolecular distances and allows to
compute with high accuracy a large portion of the dissociation curve at the
cost of a single CCSD(T) calculation. The accuracy of the present procedure is
assessed for a series of noncovalently-interacting test systems: the obtained
results reproduce CCSD(T) quality in all cases and definitely outperform
conventional MP2, CCSD and SCS-MP2 results. The difficult case of the Beryllium
dimer is also considered.


title: Entanglement in Classical Optics

abstract:
  The emerging field of entanglement or nonseparability in classical optics is
reviewed, and its similarities with and differences from quantum entanglement
clearly pointed out through a recapitulation of Hilbert spaces in general, the
special restrictions on Hilbert spaces imposed in quantum mechanics and the
role of Hilbert spaces in classical polarization optics. The production of
Bell-like states in classical polarization optics is discussed, and new
theorems are proved to discriminate between separable and nonseparable states
in classical wave optics where no discreteness is involved. The influence of
the Pancharatnam phase on a classical Bell-like state is deived. Finally, to
what extent classical polarization optics can be used to simulate quantum
information processing tasks is also discussed. This should be of great
practical importance because coherence and entanglement are robust in classical
optics but not in quantum systems.


title: Effective theory for quantum gravity

abstract:
  In this paper, we discuss an effective theory for quantum gravity and discuss
the bounds on the parameters of this effective action. In particular we show
that measurement in pulsars binary systems are unlikely to improve the bounds
on the coefficients of the $R^2$ and $R_{\mu\nu} R^{\mu\nu}$ terms obtained
from probes of Newton's potential performed on Earth. Furthermore, we argue
that if the coefficients of these terms are induced by quantum gravity, they
should be at most of order unity since $R^2$ and $R_{\mu\nu} R^{\mu\nu}$ are
dimension four operators. The same applies to the non-minimal coupling of the
Higgs boson to the Ricci scalar.


title: In-situ EXAFS study on the thermal decomposition of TiH2

abstract:
  Thermal decomposition behaviors of TiH2 powder under a flowing helium
atmosphere and in a low vacuum condition have been studied by using in-situ
EXAFS technique. By an EXAFS analysis containing the multiple scattering paths
including H atoms, the changes of hydrogen stoichiometric ratio and the phase
transformation sequence are obtained. The results demonstrate that the initial
decomposition temperature is dependent on experimental conditions, which
occurs, respectively, at about 300 and 400 degree in a low vacuum condition and
under a flowing helium atmosphere. During the decomposition process of TiH2 in
a low vacuum condition, the sample experiences a phase change process:
{\delta}(TiH2) - {\delta}(TiHx) - {\delta}(TiHx)+{\beta}(TiHx) -
{\delta}(TiHx)+{\beta}(TiHx)+{\alpha}(Ti) - {\beta}(TiHx)+{\alpha}(Ti) -
{\alpha}(Ti)+{\beta}(Ti). This study offers a way to detect the structural
information of hydrogen. A detailed discussion about the decomposition process
of TiH2 is given in this paper.


title:
APEX/SABOCA observations of small-scale structure of infrared-dark
  clouds I. Early evolutionary stages of star-forming cores

abstract:
  Infrared-dark clouds (IRDCs) harbor the early phases of cluster and high-mass
star formation and are comprised of cold (~20 K), dense (n > 10$^4$ cm$^{-3}$)
gas. The spectral energy distribution (SED) of IRDCs is dominated by the
far-infrared and millimeter wavelength regime, and our initial Herschel study
examined IRDCs at the peak of the SED with high angular resolution. Here we
present a follow-up study using the SABOCA instrument on APEX which delivers
7.8" angular resolution at 350 micron, matching the resolution we achieved with
Herschel/PACS, and allowing us to characterize substructure on ~0.1pc scales.
Our sample of 11 nearby IRDCs are a mix of filamentary and clumpy morphologies,
and the filamentary clouds show significant hierarchical structure, while the
clumpy IRDCs exhibit little hierarchical structure. All IRDCs, regardless of
morphology, have about 14% of their total mass in small scale core-like
structures which roughly follow a trend of constant volume density over all
size scales. Out of the 89 protostellar cores we identified in this sample with
Herschel, we recover 40 of the brightest and re-fit their SEDs and find their
properties agree fairly well with our previous estimates (<T> ~ 19K). We detect
a new population of "cold cores" which have no 70 micron counterpart, but are
100 and 160 micron-bright, with colder temperatures (<T> ~ 16K). This latter
population, along with SABOCA-only detections, are predominantly low-mass
objects, but their evolutionary diagnostics are consistent with the earliest
starless or prestellar phase of cores in IRDCs.


title: Sequence selection in an autocatalytic binary polymer model

abstract:
  An autocatalytic pattern matching polymer system is studied as an abstract
model for chemical ecosystem evolution. Highly ordered populations with
particular sequence patterns appear spontaneously out of a vast number of
possible states. The interplay between the selected microscopic sequence
patterns and the macroscopic cooperative structures is examined. Stability,
fluctuations, and evolutionary selection mechanisms are investigated for the
involved self-organizing processes.


title: Simulator for Microlens Planet Surveys

abstract:
  We summarize the status of a computer simulator for microlens planet surveys.
The simulator generates synthetic light curves of microlensing events observed
with specified networks of telescopes over specified periods of time.
Particular attention is paid to models for sky brightness and seeing,
calibrated by fitting to data from the OGLE survey and RoboNet observations in
2011. Time intervals during which events are observable are identified by
accounting for positions of the Sun and the Moon, and other restrictions on
telescope pointing. Simulated observations are then generated for an algorithm
that adjusts target priorities in real time with the aim of maximizing planet
detection zone area summed over all the available events. The exoplanet
detection capability of observations was compared for several telescopes.


title: Effect of strong wakes on waves in two-dimensional plasma crystals

abstract:
  We study effects of the particle-wake interactions on the dispersion and
polarization of dust lattice wave modes in two-dimensional plasma crystals.
Most notably, the wake-induced coupling between the modes causes the branches
to "attract" each other, and their polarizations become elliptical. Upon the
mode hybridization the major axes of the ellipses (remaining mutually
orthogonal) rotate by $45^\circ$. To demonstrate importance of the obtained
results for experiments, we plot spectral densities of the longitudinal and
transverse waves revealing distinct fingerprints of the mixed polarization.
Furthermore, we show that at strong coupling the hybrid mode is significantly
shifted towards smaller wave numbers, away from the border of the first
Brillouin zone (where the hybrid mode is localized for a weak coupling).