title: Adaptive reference-free compression of sequence quality scores

abstract:
  Motivation:
  Rapid technological progress in DNA sequencing has stimulated interest in
compressing the vast datasets that are now routinely produced. Relatively
little attention has been paid to compressing the quality scores that are
assigned to each sequence, even though these scores may be harder to compress
than the sequences themselves. By aggregating a set of reads into a compressed
index, we find that the majority of bases can be predicted from the sequence of
bases that are adjacent to them and hence are likely to be less informative for
variant calling or other applications. The quality scores for such bases are
aggressively compressed, leaving a relatively small number at full resolution.
Since our approach relies directly on redundancy present in the reads, it does
not need a reference sequence and is therefore applicable to data from
metagenomics and de novo experiments as well as to resequencing data.
  Results:
  We show that a conservative smoothing strategy affecting 75% of the quality
scores above Q2 leads to an overall quality score compression of 1 bit per
value with a negligible effect on variant calling. A compression of 0.68 bit
per quality value is achieved using a more aggressive smoothing strategy, again
with a very small effect on variant calling.
  Availability:
  Code to construct the BWT and LCP-array on large genomic data sets is part of
the BEETL library, available as a github respository at
http://git@github.com:BEETL/BEETL.git .


title: Lightweight LCP Construction for Next-Generation Sequencing Datasets

abstract:
  The advent of "next-generation" DNA sequencing (NGS) technologies has meant
that collections of hundreds of millions of DNA sequences are now commonplace
in bioinformatics. Knowing the longest common prefix array (LCP) of such a
collection would facilitate the rapid computation of maximal exact matches,
shortest unique substrings and shortest absent words. CPU-efficient algorithms
for computing the LCP of a string have been described in the literature, but
require the presence in RAM of large data structures. This prevents such
methods from being feasible for NGS datasets.
  In this paper we propose the first lightweight method that simultaneously
computes, via sequential scans, the LCP and BWT of very large collections of
sequences. Computational results on collections as large as 800 million
100-mers demonstrate that our algorithm scales to the vast sequence collections
encountered in human whole genome sequencing experiments.


title:
On some properties of the Mittag-Leffler function $E_\alpha(-t^\alpha)$,
  completely monotone for $t > 0$ with $0 < \alpha < 1$

abstract:
  We analyse some peculiar properties of the function of the Mittag-Leffler
(M-L) type, $e_\alpha(t):= E_\alpha(-t^\alpha)$ for $0 <\alpha < 1$ and $t >
0$, which is known to be completely monotone (CM) with a non negative spectrum
of frequencies and times, suitable to model fractional relaxation processes. We
first note that these two spectra coincide so providing a universal scaling
property of this function. Furthermore, we consider the problem of
approximating our M-L function with simpler CM functions for small and large
times. We provide two different sets of elementary CM functions that are
asymptotically equivalent to $e_\alpha(t)$ as $t \to 0$ and $t \to \infty$.

categories: math-ph cs.NA math.CA math.CV math.MP math.NA


title:
Higher order singletons, partially massless fields and their boundary
  values in the ambient approach

abstract:
  Using ambient space we develop a fully gauge and o(d,2) covariant approach to
boundary values of AdS(d+1) gauge fields. It is applied to the study of
(partially) massless fields in the bulk and (higher-order) conformal scalars,
i.e. singletons, as well as (higher-depth) conformal gauge fields on the
boundary. In particular, we identify the corresponding Fradkin-Tseytlin
equations as obstructions to the extension of the off-shell boundary value to
the bulk, generalizing the usual considerations for the holographic anomalies
to the partially massless fields. We also relate the background fields for the
higher-order singleton to the boundary values of partially massless fields and
prove the appropriate generalization of the Flato-Fronsdal theorem, which is in
agreement with the known structure of symmetries for the higher-order wave
operator. All these facts support the following generalization of the
higher-spin holographic duality: the O(N) model at a multicritical isotropic
Lifshitz point should be dual to the theory of partially massless symmetric
tensor fields described by the Vasiliev equations based on the higher-order
singleton symmetry algebra.


title: Problems with Mannheim's conformal gravity program

abstract:
  We show that Mannheim's conformal gravity program, whose potential has a term
proportional to $1/r$ and another term proportional to $r$, does not reduce to
Newtonian gravity at short distances, unless one assumes undesirable
singularities of the mass density of the proton. Therefore, despite the claim
that it successfully explains galaxy rotation curves, unless one assumes the
singularities, it seems to be falsified by numerous Cavendish-type experiments
performed at laboratories on Earth whose work have not found any deviations
from Newton's theory. Moreover, it can be shown that as long as the total mass
of the proton is positive, Mannheim's conformal gravity program leads to
negative linear potential, which is problematic from the point of view of
fitting galaxy rotation curves, which necessarily requires positive linear
potential.


title: Regular sequences and ZD-modules

abstract:
  Let R be a Noetherian ring, I an ideal of R and M a ZD-module. Let S be a
Melkersson subcategory with respect to I such that M/IM doesn't belong to S. We
show that all maximal S-sequences on M in I, have equal length. If this common
length is denoted by S-depth_I(M), then S-depth_I(M) = inf{i : H^i_I(M) doesn't
belong to S}.


title: On Spaces of Infinitesimal Motions and Henneberg Extensions

abstract:
  We investigate certain spaces of infinitesimal motions arising naturally in
the rigidity theory of bar and joint frameworks. We prove some structure
theorems for these spaces and as a consequence are able to deduce some special
cases of a long standing conjecture of Graver, Tay and Whiteley concerning
Henneberg extensions and generically rigid graphs.


title: 125 GeV Higgs Boson signal within the complex NMSSM

abstract:
  While the properties of the 125 GeV Higgs boson-like particle observed by the
ATLAS and CMS collaborations are largely compatible with those predicted for
the Standard Model state, significant deviations are present in some cases. We,
therefore, test the viability of a Beyond the Standard Model scenario based on
Supersymmetry, the CP-violating Next-to-Minimal Supersymmetric Standard Model,
against the corresponding experimental observations. Namely, we identify
possible model configurations in which one of its Higgs bosons is consistent
with the LHC observation and evaluate the role of the explicit complex phases
in both the mass and diphoton decay of such a Higgs boson. Through a detailed
analysis of some benchmark points corresponding to each of these
configurations, we highlight the impact of the CP-violating phases on the model
predictions compared to the CP-conserving case.


title:
Reconstruction of Tip-Surface Interactions with Multimodal
  Intermodulation Atomic Force Microscopy

abstract:
  We propose a theoretical framework for reconstructing tip-surface
interactions using the intermodulation technique when more than one eigenmode
is required to describe the cantilever motion. Two particular cases of bimodal
motion are studied numerically: one bending and one torsional mode, and two
bending modes. We demonstrate the possibility of accurate reconstruction of a
two-dimensional conservative force field for the former case, while dissipative
forces are studied for the latter.


title: The classical limit of quantum optics: not what it seems at first sight

abstract:
  What is light and how to describe it has always been a central subject in
physics. As our understanding has increased, so have our theories changed:
Geometrical optics, wave optics and quantum optics are increasingly
sophisticated descriptions, each referring to a larger class of phenomena than
its predecessor. But how exactly are these theories related? How and when wave
optics reduces to geometric optics is a rather simple problem. Similarly, how
quantum optics reduces to wave optics has been considered to be a very simple
business as well. It's not so. As we show here the classical limit of quantum
optics is a far more complicated issue; it is in fact dramatically more
involved and it requires a complete revision of all our intuitions. The revised
intuitions can then serve as a guide to finding novel quantum effects.


title: Big Deformation in 17C

abstract:
  Reaction- and interaction cross sections of 17C on a carbon target have been
reanalyzed by use of the modified Glauber model. The analysis with a deformed
Woods-Saxon density/potential suggests a big deformation structure for 17C. The
existence of a tail in the density distribution supports its possibility of
being a one-neutron halo structure. Under a deformed core plus single-particle
assumption, analysis shows a dominant d-wave of the valence neutron in 17C. Key
words Cross section, Glauber model, Density distribution, Halo, Deformation.


title: Testability of the Higgs inflation scenario in a radiative seesaw model

abstract:
  The Higgs inflation scenario is an approach to realize the inflation, in
which the Higgs boson plays a role of the inflaton without introducing a new
particle. We investigate a Higgs inflation scenario in the so-called radiative
seesaw model proposed by E. Ma. We find that a part of parameter regions where
additional scalar fields can play a role of an inflaton is compatible with the
current LHC results, the current data from neutrino experiments and those of
the dark matter abundance as well as the direct search. We show that we can
partially test this model by measuring masses of scalar bosons at the
International Linear Collider.


title: Traveling Waves in 2D Hexagonal Granular Crystal Lattices

abstract:
  We describe the dynamic response of a two-dimensional hexagonal packing of
uncompressed stainless steel spheres excited by localized impulsive loadings.
After the initial impact strikes the system, a characteristic wave structure
emerges and continuously decays as it propagates through the lattice. Using an
extension of the binary collision approximation (BCA) for one-dimensional
chains, we predict its decay rate, which compares well with numerical
simulations and experimental data. While the hexagonal lattice does not support
constant speed traveling waves, we provide scaling relations that characterize
the power law decay of the wave velocity. Lastly, we discuss the effects of
weak disorder on the directional amplitude decay rates.


title:
An Optimal Algorithm for the Euclidean Bottleneck Full Steiner Tree
  Problem

abstract:
  Let $P$ and $S$ be two disjoint sets of $n$ and $m$ points in the plane,
respectively. We consider the problem of computing a Steiner tree whose Steiner
vertices belong to $S$, in which each point of $P$ is a leaf, and whose longest
edge length is minimum. We present an algorithm that computes such a tree in
$O((n+m)\log m)$ time, improving the previously best result by a logarithmic
factor. We also prove a matching lower bound in the algebraic computation tree
model.


title:
Azimuthal Anisotropy in U+U Collisions at $\sqrt{s_{NN}} = 193 $ GeV
  with STAR Detector at RHIC

abstract:
  We report the measurement of first (\textit {n} = 1) and higher
order(\textit{n} = 2-5) harmonic coefficients ($v_{n}$) of the azimuthal
anisotropy in the distribution of the particles produced in U+U collisions at
$\sqrt{s_{NN}}$ =193 GeV, recorded with the STAR detector at RHIC. The
differential measurement of $(v_{n})$ is presented as a function of transverse
momentum ($p_{T}$) and centrality. We also present $v_{n}$ measurement in the
ultra-central collisions. These data may provide strong constraints on the
theoretical models of the initial condition in heavy ion collisions and the
transport properties of the produced medium.


title: On the Mechanical Interaction of Light With Homogeneous Liquids

abstract:
  We investigate one of the consequences of the three competing models
describing the mechanical interaction of light with a dielectric medium.
According to both the Abraham and Minkowski models the time-averaged force
density is zero inside a homogeneous dielectric, whereas the induced-current
Lorentz force model predicts a non-zero force density. We argue that the latter
force, if exists, could drive a hydrodynamic flow inside a homogeneous fluid.
Our numerical experiments show that such flows have distinct spatial patterns
and may influence the dynamics of particles in a water-based single-beam
optical trap.


title: A representative sample of Be stars V: H{\alpha} variability

abstract:
  Aims. We attempt to determine if a dependency on spectral subtype or vsini
exists for stars undergoing phase-changes between B and Be states, as well as
for those stars exhibiting variability in H{\alpha} emission. Methods. We
analyse the changes in H{\alpha} line strength for a sample of 55 Be stars of
varying spectral types and luminosity classes using five epochs of observations
taken over a ten year period between 1998 and 2010. Results. We find i) that
the typical timescale between which full phase transitions occur is most likely
of the order of centuries, although no dependency on spectral subtype or vsini
could be determined due to the low frequency of phase-changing events observed
in our sample, ii) that stars with earlier spectral types and larger values of
vsini show a greater degree of variability in H{\alpha} emission over the
timescales probed in this study, and iii) a trend of increasing variability
between the shortest and longest baselines for stars of later spectral types
and with smaller values of vsini.


title:
A lower bound for the Lyapounov exponents of the random Schrodinger
  operator on a strip

abstract:
  We consider the random Schrodinger operator on a strip of width $W$, assuming
the site distribution of bounded density. It is shown that the positive
Lyapounov exponents satisfy a lower bound roughly exponential in $-W$ or $W\to
\infty$. The argument proceeds directly by establishing Green's function decay,
but does not appeal to Furstenberg's random matrix theory on the strip. One
ingredient involved is the construction of `barriers' using the RSO theory on
$\mathbb Z$.


title: Upper-bounding the k-colorability threshold by counting covers

abstract:
  Let $G(n,m)$ be the random graph on $n$ vertices with $m$ edges. Let $d=2m/n$
be its average degree. We prove that $G(n,m)$ fails to be $k$-colorable with
high probability if $d>2k\ln k-\ln k-1+o_k(1)$. This matches a conjecture put
forward on the basis of sophisticated but non-rigorous statistical physics
ideas (Krzakala, Pagnani, Weigt 2004). The proof is based on applying the first
moment method to the number of "covers", a physics-inspired concept. By
comparison, a standard first moment over the number of $k$-colorings shows that
$\gnm$ is not $k$-colorable with high probability if $d>2k\ln k-\ln k$.


title: Twisted cubics on cubic fourfolds

abstract:
  We construct a new twenty-dimensional family of projective eight-dimensional
irreducible holomorphic symplectic manifolds: the compactified moduli space
M_3(Y) of twisted cubics on a smooth cubic fourfold Y that does not contain a
plane is shown to be smooth and to admit a contraction M_3(Y) -> Z(Y) to a
projective eight-dimensional symplectic manifold Z(Y). The construction is
based on results on linear determinantal representations of singular cubic
surfaces.


title: Species dynamics in the two-parameter Poisson-Dirichlet diffusion model

abstract:
  The recently introduced two-parameter infinitely-many neutral alleles model
extends the celebrated one-parameter version, related to Kingman's
distribution, to diffusive two-parameter Poisson-Dirichlet frequencies. Here we
investigate the dynamics driving the species heterogeneity underlying the
two-parameter model. First we show that a suitable normalization of the number
of species is driven by a critical continuous-state branching process with
immigration. Secondly, we provide a finite-dimensional construction of the
two-parameter model, obtained by means of a sequence of Feller diffusions of
Wright-Fisher flavor which feature finitely-many types and inhomogeneous
mutation rates. Both results provide insight into the mathematical properties
and biological interpretation of the two-parameter model, showing that it is
structurally different from the one-parameter case in that the frequencies
dynamics are driven by state-dependent rather than constant quantities.


title: Implication of a vanishing element in 3+1 Scenario

abstract:
  In this paper we study the phenomenological implications of the one zero
textures of low energy neutrino mass matrices in presence of a sterile
neutrino. We consider the 3+1 scheme and use the results from global fit for
short baseline neutrino oscillation data which provides the bounds on the three
additional mixing angles. We find that the mass matrix elements $m_{\alpha
\beta}$ ($\alpha, \beta = e, \mu, \tau$) involving only the active states can
assume vanishing values in the allowed parameter space for all the mass
spectrum. Among the mass matrix elements connecting the active and sterile
states, $m_{es}$ and $m_{\mu s}$ can become small only for the quasi-degenerate
neutrinos. The element $m_{\tau s}$ on the other hand can vanish even for lower
values of masses since the 3-4 mixing angle only has an upper bound from
current data. The mass matrix element ($m_{ss}$) involving only the sterile
state stays $\sim$ $\mathcal{O}$(1) eV in the whole parameter region. We study
the possible correlations between the sterile mixing angles and the Majorana
phases to give a zero element in the mass matrix.


title: Cosmological magnetic field correlators from blazar induced cascade

abstract:
  TeV blazars offer an exciting prospect for discovering cosmological magnetic
fields and for probing high energy processes, including CP violation, in the
early universe. We propose a method for reconstructing both the non-helical and
the helical magnetic field correlators using observations of cascade photons
from TeV blazars.


title:
Space-filling Latin Hypercube Designs based on Randomization
  Restrictions in Factorial Experiments

abstract:
  Latin hypercube designs (LHDs) with space-filling properties are widely used
for emulating computer simulators. Over the last three decades, a wide spectrum
of LHDs have been proposed with space-filling criteria like minimum correlation
among factors, maximin interpoint distance, and orthogonality among the factors
via orthogonal arrays (OAs). Projective geometric structures like spreads,
covers and stars of PG(p-1,q) can be used to characterize the randomization
restriction of multistage factorial experiments. These geometric structures can
also be used for constructing OAs and nearly OAs (NOAs). In this paper, we
present a new class of space-filling LHDs based on NOAs derived from stars of
PG(p-1, 2).


title: Weyl fermions and the anomalous Hall effect in metallic ferromagnets

abstract:
  We reconsider the problem of the anomalous Hall effect in ferromagnetic
SrRuO$_3$, incorporating insights from the recently developed theory of Weyl
semimetals. We demonstrate that SrRuO$_3$ possesses a large number of Weyl
nodes, separated in momentum space, in its bandstructure. While the nodes
normally do not coincide with the Fermi energy, unless the material is doped,
we show that even the nodes inside the Fermi sea have a significant effect on
the physical properties of the material. In particular, we show that the common
belief that (non-quantized part of) the intrinsic anomalous Hall conductivity
of a ferromagnetic metal is entirely a Fermi surface property, is incorrect:
there generally exists a contribution to the anomalous Hall conductivity that
arises from topological Fermi-arc surface states, associated with the Weyl
nodes, which is of the same order of magnitude as the Fermi surface
contribution.


title:
Weighted Paley-Wiener spaces and mountain chain axioms: a detailed
  exposition

abstract:
  The present work reviews the second half of Lyubarskii and Seip's paper,
Weighted Paley--Wiener Spaces. Axioms defining a larger class of de Branges
spaces are abstracted, allowing us to state and prove their results at a higher
level of generality.


title: A 2.0 Gb/s Throughput Decoder for QC-LDPC Convolutional Codes

abstract:
  This paper propose a decoder architecture for low-density parity-check
convolutional code (LDPCCC). Specifically, the LDPCCC is derived from a
quasi-cyclic (QC) LDPC block code. By making use of the quasi-cyclic structure,
the proposed LDPCCC decoder adopts a dynamic message storage in the memory and
uses a simple address controller. The decoder efficiently combines the memories
in the pipelining processors into a large memory block so as to take advantage
of the data-width of the embedded memory in a modern field-programmable gate
array (FPGA). A rate-5/6 QC-LDPCCC has been implemented on an Altera Stratix
FPGA. It achieves up to 2.0 Gb/s throughput with a clock frequency of 100 MHz.
Moreover, the decoder displays an excellent error performance of lower than
$10^{-13}$ at a bit-energy-to-noise-power-spectral-density ratio ($E_b/N_0$) of
3.55 dB.


title:
The Microlensing Event Rate and Optical Depth Toward the Galactic Bulge
  from MOA-II

abstract:
  We present measurements of the microlensing optical depth and event rate
toward the Galactic Bulge based on two years of the MOA-II survey. This sample
contains ~1000 microlensing events, with an Einstein Radius crossing time of
t_E < 200 days between -5 <l< 10 degree and -7 <b< -1 degree. Our event rate
and optical depth analysis uses 474 events with well defined microlensing
parameters. In the central fields with |l|< 5 degree, we find an event rates of
\Gamma = [2.39+/-1.1]e^{[0.60\pm0.05](3-|b|)}x 10^{-5}/star/yr and an optical
depth of \tau_{200} = [2.35+/-0.18]e^{[0.51+/-0.07](3-|b|)}x 10^{-6} for the
427 events using all sources brighter than I_s = 20 mag centered at
(l,b)=(0.38, -3.72). We find that the event rate is maximized at low latitudes
and a longitude of $l~1 degree. For the 111 events in 3.2 deg^2 of the central
Galactic Bulge at |b| < 3.0 degree and 0.0 < l < 2.0, centered at (l,b)=(0.97,
-2.26), we find \Gamma = 4.57_{-0.46}^{+0.51} x 10^{-5}/star/yr and \tau_{200}
= 3.64_{-0.45}^{+ 0.51} x 10^{-6}. We also consider a Red Clump Giant (RCG)
star sample with I_s<17.5 mag. Our results are consistent with previous optical
depth measurements. We find that the previously observed difference in optical
depth measurements between all-source and RCG samples may be largely due to
statistical fluctuations. These event rate measurements towards the central
galactic bulge are necessary to predict the microlensing event rate and to
optimize the survey fields in the future space mission such as WFIRST.


title: A Community Based Algorithm for Large Scale Web Service Composition

abstract:
  Web service composition is the process of synthesizing a new composite
service using a set of available Web services in order to satisfy a client
request that cannot be treated by any available Web services. The Web services
space is a dynamic environment characterized by a huge number of elements.
Furthermore, many Web services are offering similar functionalities. In this
paper we propose a model for Web service composition designed to address the
scale effect and the redundancy issue. The Web services space is represented by
a two-layered network architecture. A concrete similarity network layer
organizes the Web services operations into communities of functionally similar
operations. An abstract interaction network layer represents the composition
relationships between the sets of communities. Composition synthesis is
performed by a two-phased graph search algorithm. First, the interaction
network is mined in order to discover abstract solutions to the request goal.
Then, the abstract compositions are instantiated with concrete operations
selected from the similarity network. This strategy allows an efficient
exploration of the Web services space. Furthermore, operations grouped in a
community can be easily substituted if necessary during the composition's
synthesis's process.


title:
Regularity equivalence of the Szeg\"o projection and the complex Green
  operator

abstract:
  In this paper we prove that on a CR manifold of hypersurface type that
satisfies the weak $Y(q)$ condition, the complex Green operator $G_q$ is
exactly (globally) regular if and only if the Szeg\"o projections $S_{q-1},
S_q$ and a third orthogonal projection $S'_{q+1}$ are exactly (globally)
regular. The projection $S'_{q+1}$ is closely related to the Szeg\"o projection
$S_{q+1}$ and actually coincides with it if the space of harmonic
$(0,q+1)$-forms is trivial.
  This result extends the important and by now classical result by H. Boas and
E. Straube on the equivalence of the regularity of the $\bar\partial$-Neumann
operator and the Bergman projections on a smoothly bounded pseudoconvex domain.
We also prove an extension of this result to the case of bounded smooth domains
satisfying the weak $Z(q)$ condition on a Stein manifold.


title: A Comparative Study of Web Services Composition Networks

abstract:
  Web services growth makes the composition process a hard task to solve. This
numerous interacting elements can be adequately represented by a network.
Discovery and composition can benefit from the knowledge of the network
structure. In this paper, we investigate the topological properties of two
models of syntactic and semantic Web services composition networks: dependency
and interaction. Results show that they share a similar organization
characterized by the small-world property, a heavy-tailed degree distribution
and a low transitivity value. Furthermore, the networks are disassortative.


title: Analyzing Web Services Networks: a WS-NEXT Application

abstract:
  Web services represent a system with a huge number of units and many various
and complex interactions. Complex networks as a tool for modelling and
analyzing natural environments seem to be well adapted to such a complex
system. To describe a set of Web services we propose three Web services network
models based on the notions of dependency, interaction and similarity. Using
the WS-NEXT extractor we instantiate the models with a collection of Web
services descriptions. We take advantage of complex network properties to
provide an analyzis of the Web services networks. Those networks and the
knowledge of their toplogical properties can be exploited for the discovery and
composition processes.


title:
Benefits of Semantics on Web Service Composition from a Complex Network
  Perspective

abstract:
  The number of publicly available Web services (WS) is continuously growing,
and in parallel, we are witnessing a rapid development in semantic-related web
technologies. The intersection of the semantic web and WS allows the
development of semantic WS. In this work, we adopt a complex network
perspective to perform a comparative analysis of the syntactic and semantic
approaches used to describe WS. From a collection of publicly available WS
descriptions, we extract syntactic and semantic WS interaction networks. We
take advantage of tools from the complex network field to analyze them and
determine their properties. We show that WS interaction networks exhibit some
of the typical characteristics observed in real-world networks, such as short
average distance between nodes and community structure. By comparing syntactic
and semantic networks through their properties, we show the introduction of
semantics in WS descriptions should improve the composition process.


title: Spin locking at the apex of nano-scale platinum tips

abstract:
  Nanostructures based on platinum, such as small clusters or STM-tips, often
exhibit an atomistic structure that relies upon one or very few strongly
under-coordinated platinum atoms. Here, we analyze a paradigmatic example, an
apex atom on a pyramidal platinum cluster employing the density functional
theory. We show that such a pristine platinum tip exhibits a spin polarization
of the apex atom with a remarkable robustness. Due to a depletion of the
projected density of states at the apex position, the apex-magnetization is
efficiently locked to about 0.6$\mu_\text{B}$.


title: Coherent beam shaping using two-dimensional photonic crystals

abstract:
  Optical devices based on photonic crystals such as waveguides, lenses and
beam-shapers, have received considerable theoretical and experimental attention
in recent years. The production of these devices has been facilitated by the
wide availability of silicon-on-insulator fabrication techniques. In this
theoretical work, we show the possibility to design a coherent PhC-based
beam-shaper. The basic photonic geometry used is a 2D square lattice of air
holes in a high-index dielectric core. We formulate the beam shaping problem in
terms of objective functions related to the amplitude and phase profile of the
generated beam. We then use a parallel tabu search algorithm to minimize the
two objectives simultaneously. Our results show that optimization of several
attributes in integrated photonics design is well within reach of current
algorithms.


title: MATAWS: A Multimodal Approach for Automatic WS Semantic Annotation

abstract:
  Many recent works aim at developing methods and tools for the processing of
semantic Web services. In order to be properly tested, these tools must be
applied to an appropriate benchmark, taking the form of a collection of
semantic WS descriptions. However, all of the existing publicly available
collections are limited by their size or their realism (use of randomly
generated or resampled descriptions). Larger and realistic syntactic (WSDL)
collections exist, but their semantic annotation requires a certain level of
automation, due to the number of operations to be processed. In this article,
we propose a fully automatic method to semantically annotate such large WS
collections. Our approach is multimodal, in the sense it takes advantage of the
latent semantics present not only in the parameter names, but also in the type
names and structures. Concept-to-word association is performed by using Sigma,
a mapping of WordNet to the SUMO ontology. After having described in details
our annotation method, we apply it to the larger collection of real-world
syntactic WS descriptions we could find, and assess its efficiency.


title: Similartity Network For Semantic Web Services Substitution

abstract:
  Web services substitution is one of the most challenging tasks for automating
the composition process of multiple Web services. It aims to improve
performances and to deal efficiently with Web services failures. Many existing
solutions have approached the problem through classification of substitutable
Web services. To go a step further, we propose in this paper a network based
approach where nodes are Web services operations and links join similar
operations. Four similarity measures based on the comparison of input and
output parameters values of Web services operations are presented. A
comparative evaluation of the topological structure of the corresponding
networks is performed on a benchmark of semantically annotated Web services.
Results show that this approach allows a more detailed analysis of
substitutable Web services.


title: Topological Properties of Web Services Similarity Networks

abstract:
  The number of publicly available Web services (WS) is continuously growing.
To perform efficient WS discovery, it is desirable to organize the WS space.
Works in this direction propose to group WS according to certain shared
properties. Such groups commonly called communities are based either on
similarity or on interaction between WS. In this paper we focus on the former,
and propose a new network-based approach to extract communities from a WS
collection. This process is three-stepped: first we define several similarity
functions able to compare WS operations, second we use them to build so-called
similarity networks, and third we identify communities under the form of
specific structures in these networks. We apply our method on a collection of
real-world WS and comment the resulting communities. Finally, we additionally
provide an analysis and an interpretation of our similarity networks with a
complex networks perspective.


title: Excitable elements controlled by noise and network structure

abstract:
  We study collective dynamics of complex networks of stochastic excitable
elements, active rotators. In the thermodynamic limit of infinite number of
elements, we apply a mean-field theory for the network and then use a Gaussian
approximation to obtain a closed set of deterministic differential equations.
These equations govern the order parameters of the network. We find that a
uniform decrease in the number of connections per element in a homogeneous
network merely shifts the bifurcation thresholds without producing qualitative
changes in the network dynamics. In contrast, heterogeneity in the number of
connections leads to bifurcations in the excitable regime. In particular we
show that a critical value of noise intensity for the saddle-node bifurcation
decreases with growing connectivity variance. The corresponding critical values
for the onset of global oscillations (Hopf bifurcation) show a non-monotone
dependency on the structural heterogeneity, displaying a minimum at moderate
connectivity variances.


title:
Electronic structure of the kagome staircase compounds Ni3V2O8 and
  Co3V2O8

abstract:
  The electronic structure of the kagome staircase compounds, Ni3V2O8 and
Co3V2O8, has been investigated using soft x-ray absorption, soft x-ray
emission, and resonant inelastic x-ray scattering (RIXS). Comparison between
the two compounds, and with first principles band structure calculations and
crystal-field multiplet models, provide unique insight into the electronic
structure of the two materials. Whereas the location of the narrow (Ni,Co) d
bands is predicted to be close to EF, we experimentally find they lie deeper in
the occupied O 2p and unoccupied V 3d manifolds, and determine their energy via
measured charge-transfer excitations. Additionally, we find evidence for a dd
excitation at 1.5 eV in Ni3V2O8, suggesting the V d states may be weakly
occupied in this compound, contrary to Co3V2O8. Good agreement is found between
the crystal-field dd excitations observed in the experiment and predicted by
atomic multiplet theory.


title:
Transmission of Megawatt Relativistic Electron Beams Through Millimeter
  Apertures

abstract:
  High power, relativistic electron beams from energy recovery linacs have
great potential to realize new experimental paradigms for pioneering innovation
in fundamental and applied research. A major design consideration for this new
generation of experimental capabilities is the understanding of the halo
associated with these bright, intense beams. In this Letter, we report on
measurements performed using the 100 MeV, 430 kWatt CW electron beam from the
energy recovery linac at the Jefferson Laboratory's Free Electron Laser
facility as it traversed a set of small apertures in a 127 mm long aluminum
block. Thermal measurements of the block together with neutron measurements
near the beam-target interaction point yielded a consistent understanding of
the beam losses. These were determined to be 3 ppm through a 2 mm diameter
aperture and were maintained during a 7 hour continuous run.


title:
On the relation between Lebesgue summability and some other summation
  methods

abstract:
  It is shown that if $$ \sum_{n=1}^{N}n\left|c_{n}\right|=O(N), $$ then
Lebesgue summability, $(\mathrm{C},\beta)$ summability ($\beta>0$), Abel
summability, Riemann summability, and $(\gamma,\kappa)$ summability
($\kappa\geq 1$) of the series $\sum_{n=0}^{\infty}c_{n}$ are all equivalent to
one another.


title: On spectral radius of strongly connected digraphs

abstract:
  We determine the digraphs which achieve the second, the third and the fourth
minimum spectral radii respectively among strongly connected digraphs of order
$n\ge 4$, and thus we answer affirmatively the problem whether the unique
digraph which achieves the minimum spectral radius among all strongly connected
bicyclic digraphs of order $n$ achieves the second minimum spectral radius
among all strongly connected digraphs of order $n$ for $n\ge 4$ proposed in
  [H. Lin, J. Shu, A note on the spectral characterization of strongly
connected bicyclic digraphs, Linear Algebra Appl. 436 (2012) 2524--2530]. We
also discuss the strongly connected bicyclic digraphs with small and large
spectral radii respectively.


title: Classification of tile digit sets as product-forms

abstract:
  Let $A$ be an expanding matrix on ${\Bbb R}^s$ with integral entries. A
fundamental question in the fractal tiling theory is to understand the
structure of the digit set ${\mathcal D}\subset{\Bbb Z}^s$ so that the integral
self-affine set $T(A,\mathcal D)$ is a translational tile on ${\Bbb R}^s$. In
our previous paper, we classified such tile digit sets ${\mathcal
D}\subset{\Bbb Z}$ by expressing the mask polynomial $P_{\mathcal D}$ into
product of cyclotomic polynomials. In this paper, we first show that a tile
digit set in ${\Bbb Z}^s$ must be an integer tile (i.e. ${\mathcal
D}\oplus{\mathcal L} = {\Bbb Z}^s$ for some discrete set ${\mathcal L}$). This
allows us to combine the technique of Coven and Meyerowitz on integer tiling on
${\Bbb R}^1$ together with our previous results to characterize explicitly all
tile digit sets ${\mathcal D}\subset {\Bbb Z}$ with $A = p^{\alpha}q$ ($p, q$
distinct primes) as {\it modulo product-form} of some order, an advance of the
previously known results for $A = p^\alpha$ and $pq$.


title: Matrix Compression using the Nystro\"om Method

abstract:
  The Nystr\"{o}m method is routinely used for out-of-sample extension of
kernel matrices. We describe how this method can be applied to find the
singular value decomposition (SVD) of general matrices and the eigenvalue
decomposition (EVD) of square matrices. We take as an input a matrix $M\in
\mathbb{R}^{m\times n}$, a user defined integer $s\leq min(m,n)$ and $A_M \in
\mathbb{R}^{s\times s}$, a matrix sampled from the columns and rows of $M$.
These are used to construct an approximate rank-$s$ SVD of $M$ in
$O\left(s^2\left(m+n\right)\right)$ operations. If $M$ is square, the rank-$s$
EVD can be similarly constructed in $O\left(s^2 n\right)$ operations. Thus, the
matrix $A_M$ is a compressed version of $M$. We discuss the choice of $A_M$ and
propose an algorithm that selects a good initial sample for a pivoted version
of $M$. The proposed algorithm performs well for general matrices and kernel
matrices whose spectra exhibit fast decay.


title:
Design of a Lambda system for population transfer in superconducting
  nanocircuits

abstract:
  The implementation of a Lambda scheme in superconducting artificial atoms
could allow detec- tion of stimulated Raman adiabatic passage (STIRAP) and
other quantum manipulations in the microwave regime. However symmetries which
on one hand protect the system against decoherence, yield selection rules which
may cancel coupling to the pump external drive. The tradeoff between efficient
coupling and decoherence due to broad-band colored Noise (BBCN), which is often
the main source of decoherence is addressed, in the class of nanodevices based
on the Cooper pair box (CPB) design. We study transfer efficiency by STIRAP,
showing that substantial efficiency is achieved for off-symmetric bias only in
the charge-phase regime. We find a number of results uniquely due to
non-Markovianity of BBCN, namely: (a) the efficiency for STIRAP depends
essentially on noise channels in the trapped subspace; (b) low-frequency
fluctuations can be analyzed and represented as fictitious correlated
fluctuations of the detunings of the external drives; (c) a simple figure of
merit for design and operating prescriptions allowing the observation of STIRAP
is proposed. The emerging physical picture also applies to other classes of
coherent nanodevices subject to BBCN.


title:
The effect of the initial network configuration on preferential
  attachment

abstract:
  The classical preferential attachment model is sensitive to the choice of the
initial configuration of the network. As the number of initial nodes and their
degree grow, so does the time needed for an equilibrium degree distribution to
be established. We study this phenomenon, provide estimates of the
equilibration time, and characterize the degree distribution cutoff observed at
finite times. When the initial network is dense and exceeds a certain small
size, there is no equilibration and a suitable statistical test can always
discern the produced degree distribution from the equilibrium one. As a
by-product, the weighted Kolmogorov-Smirnov statistic is demonstrated to be
more suitable for statistical analysis of power-law distributions with cutoff
when the data is ample.

categories: physics.soc-ph cond-mat.stat-mech cs.SI physics.data-an


title:
Meta-Structures: The Search of Coherence in Collective Behaviours
  (without Physics)

abstract:
  This contribution shortly outlines and reviews a theoretical and
computational approach for a theory of change concerning systems where it is
not possible to apply the laws of motion ab initio. The concept of
meta-structure relates to the emergence of forms of spatiotemporal coherences
in collective behaviours intended as coherent sequences of multiple structures.
The essential difference compared with traditional methods is the role of the
cognitive design by the observer when identifying multiple mesoscopic
variables. The goal is both to study the "change without physics" of the
dynamics of change and to design non-catastrophic interventions having the
purpose to induce, change, keep or restore collective behaviours by influencing
-at the mesoscopic level -and not prescribing explicit rules and changes.


title:
Mean-field embedding of the dual fermion approach for correlated
  electron systems

abstract:
  To reduce the rapidly growing computational cost of the dual fermion lattice
calculation with increasing system size, we introduce two embedding schemes.
One is the real fermion embedding, and the other is the dual fermion embedding.
Our numerical tests show that the real fermion and dual fermion embedding
approaches converge to essentially the same result. The application on the
Anderson disorder and Hubbard models shows that these embedding algorithms
converge more quickly with system size as compared to the conventional dual
fermion method, for the calculation of both single-particle and two-particle
quantities.


title: Perceptron Mistake Bounds

abstract:
  We present a brief survey of existing mistake bounds and introduce novel
bounds for the Perceptron or the kernel Perceptron algorithm. Our novel bounds
generalize beyond standard margin-loss type bounds, allow for any convex and
Lipschitz loss function, and admit a very simple proof.


title:
Stratos: A Network-Aware Orchestration Layer for Virtual Middleboxes in
  Clouds

abstract:
  Enterprises want their in-cloud services to leverage the performance and
security benefits that middleboxes offer in traditional deployments. Such
virtualized deployments create new opportunities (e.g., flexible scaling) as
well as new challenges (e.g., dynamics, multiplexing) for middlebox management
tasks such as service composition and provisioning. Unfortunately, enterprises
lack systematic tools to efficiently compose and provision in-the-cloud
middleboxes and thus fall short of achieving the benefits that cloud-based
deployments can offer. To this end, we present the design and implementation of
Stratos, an orchestration layer for virtual middleboxes. Stratos provides
efficient and correct composition in the presence of dynamic scaling via
software-defined networking mechanisms. It ensures efficient and scalable
provisioning by combining middlebox-specific traffic engineering, placement,
and horizontal scaling strategies. We demonstrate the effectiveness of Stratos
using an experimental prototype testbed and large-scale simulations.


title:
A New Method to Directly Measure the Jeans Scale of the Intergalactic
  Medium Using Close Quasar Pairs

abstract:
  Although the baryons in the intergalactic medium (IGM) trace dark matter on
Mpc scales, small-scale (~100 kpc) fluctuations are suppressed by pressure
support, analogous to the classical Jeans argument. This Jeans filtering scale
has fundamental cosmological implications: it provides a thermal record of heat
injected by UV photons during reionization events, determines the clumpiness of
the IGM, and sets the minimum mass scale for gravitational collapse, a key
quantity in galaxy formation. Unfortunately, it is extremely challenging to
measure via the standard analysis of purely longitudinal Lyman-alpha forest
spectra, because the thermal Doppler broadening of absorption lines is highly
degenerate with Jeans pressure smoothing. In this work we show that the Jeans
scale can be directly measured by characterizing the coherence of correlated
Lyman-alpha absorption in quasar pairs with separations small enough to resolve
it. We present a novel technique for this purpose, based on the probability
distribution function (PDF) of phase angle differences of homologous
longitudinal Fourier modes in close quasar pair spectra. A Bayesian formalism
is introduced based on the phase angle PDF, and MCMC techniques are used to
characterize the precision of a future Jeans scale measurement, and explore
degeneracies with other thermal parameters governing the IGM. A semi-analytical
model of the IGM is used to generate a grid of 500 thermal models from a dark
matter simulation. Our full parameter study indicates that a realistic sample
of only 20 close quasar pair spectra can pinpoint the Jeans scale to ~ 5%
precision, independent of the parameters governing the temperature-density
relation of the IGM. We show that this new method is insensitive to a battery
of systematics such as continuum fitting errors, imprecise knowledge of the
noise and spectral resolution, and metal-line absorption.


title:
Charge and spin supercurrents in triplet
  superconductor--ferromagnet--singlet superconductor Josephson junctions

abstract:
  We study the Josephson effect in a triplet
superconductor--ferromagnet--singlet superconductor junction. We show that the
interaction of tunneling Cooper pairs with the interface magnetization can
permit a Josephson current at the lowest order of a tunneling Hamiltonian
perturbation theory. Two conditions must be satisfied for this to occur: the
magnetization of the ferromagnet has a component parallel to the ${\bf
d}$-vector of the triplet superconductor, and the gaps of the superconductors
have the same parity with respect to the interface momentum. The resulting
charge current displays an unconventional dependence on the orientation of the
magnetic moment and the phase difference. This is accompanied by a
phase-dependent spin current in the triplet superconductor, while a
phase-independent spin current is always present. The tunneling perturbation
theory predictions are confirmed using a numerical Green's function method. An
analytical treatment of a one-dimensional junction demonstrates that our
conclusions are robust far away from the tunneling regime, and reveals
signatures of the unconventional Josephson effect in the critical currents.


title: Experimental characterization of universal one-way quantum computing

abstract:
  We report the characterization of a universal set of logic gates for one-way
quantum computing using a four-photon `star' cluster state generated by fusing
photons from two independent photonic crystal fibre sources. We obtain a
fidelity for the cluster state of 0.66 +/- 0.01 with respect to the ideal case.
We perform quantum process tomography to completely characterize a
controlled-NOT, Hadamard and T gate all on the same compact entangled resource.
Together, these operations make up a universal set of gates such that arbitrary
quantum logic can be efficiently constructed from combinations of them. We find
process fidelities with respect to the ideal cases of 0.64 +/- 0.01 for the
CNOT, 0.67 +/- 0.03 for the Hadamard and 0.76 +/- 0.04 for the T gate. The
characterisation of these gates enables the simulation of larger protocols and
algorithms. As a basic example, we simulate a Swap gate consisting of three
concatenated CNOT gates. Our work provides some pragmatic insights into the
prospects for building up to a fully scalable and fault-tolerant one-way
quantum computer with photons in realistic conditions.


title:
Recovering Graph-Structured Activations using Adaptive Compressive
  Measurements

abstract:
  We study the localization of a cluster of activated vertices in a graph, from
adaptively designed compressive measurements. We propose a hierarchical
partitioning of the graph that groups the activated vertices into few
partitions, so that a top-down sensing procedure can identify these partitions,
and hence the activations, using few measurements. By exploiting the cluster
structure, we are able to provide localization guarantees at weaker signal to
noise ratios than in the unstructured setting. We complement this performance
guarantee with an information theoretic lower bound, providing a necessary
signal-to-noise ratio for any algorithm to successfully localize the cluster.
We verify our analysis with some simulations, demonstrating the practicality of
our algorithm.


title:
Changing topology by topological defects in three-dimensional
  topologically ordered phases

abstract:
  A hallmark feature of topologically ordered states of matter is the
dependence of ground state degeneracy (GSD) on the topology of the manifold
determined by the global shape of the system. Although the topology of a
physical system is practically hard to manipulate, recently it was shown that
in certain topologically ordered phases, topological defects can introduce
extra topological GSD. Here the topological defects can be viewed as
effectively changing the topology of the physical system. Previous studies have
been focusing on two spatial dimensions with point-like topological defects. In
three dimensions, line-like topological defects can appear. They are closed
loops in the bulk that can be linked and knotted, effectively leading to
complex three dimensional manifolds in certain topologically ordered states.
This paper studies the properties of such line-defects in a particular context:
the lattice dislocations. We give an analytical construction, together with
support from exact numerical calculations, for the dependence of the GSD on
dislocations of certain doubled versions of the exactly solvable Kitaev's toric
code models in both two and three dimensions. We find that the GSD of the 3d
model depends only on the total number of dislocation loops, no matter how they
are linked or knotted. The results are extended to Z_n generalizations of the
model. Additionally, we consider the phases in which the crystalline orders are
destroyed through proliferation of double dislocations. The resulting phases
are shown to host topological orders described by non-Abelian gauge theories.


title: Powerlaw: a Python package for analysis of heavy-tailed distributions

abstract:
  Power laws are theoretically interesting probability distributions that are
also frequently used to describe empirical data. In recent years effective
statistical methods for fitting power laws have been developed, but appropriate
use of these techniques requires significant programming and statistical
insight. In order to greatly decrease the barriers to using good statistical
methods for fitting power law distributions, we developed the powerlaw Python
package. This software package provides easy commands for basic fitting and
statistical analysis of distributions. Notably, it also seeks to support a
variety of user needs by being exhaustive in the options available to the user.
The source code is publicly available and easily extensible.


title:
Benedetto's trick and existence of rational preperiodic structures for
  quadratic polynomials

abstract:
  We refine a result of R. Benedetto in p-adic analysis in order to exhibit
infinitely many quadratic polynomials with rational coefficients having a
specified graph of rational preperiodic points.


title: Fully renormalized stress tensor correlator in flat space

abstract:
  We present a general procedure to renormalize the stress tensor two-point
correlation function on a Minkowski background in position space. The method is
shown in detail for the case of a free massive scalar field in the standard
Minkowski vacuum state, and explicit expressions are given for the counterterms
and finite parts, which are in full accordance with earlier results for the
massless case. For the general case in position space, only regularized --- but
not renormalized --- results have been obtained previously. After a Fourier
transformation to momentum space, we also check agreement with a previous
calculation there. We generalize our results to general Hadamard states.
Furthermore, the proposed procedure can presumably be generalized to the
important case of an inflationary spacetime background, where the transition to
momentum space is in general not possible.


title: Video Segmentation via Diffusion Bases

abstract:
  Identifying moving objects in a video sequence, which is produced by a static
camera, is a fundamental and critical task in many computer-vision
applications. A common approach performs background subtraction, which
identifies moving objects as the portion of a video frame that differs
significantly from a background model. A good background subtraction algorithm
has to be robust to changes in the illumination and it should avoid detecting
non-stationary background objects such as moving leaves, rain, snow, and
shadows. In addition, the internal background model should quickly respond to
changes in background such as objects that start to move or stop. We present a
new algorithm for video segmentation that processes the input video sequence as
a 3D matrix where the third axis is the time domain. Our approach identifies
the background by reducing the input dimension using the \emph{diffusion bases}
methodology. Furthermore, we describe an iterative method for extracting and
deleting the background. The algorithm has two versions and thus covers the
complete range of backgrounds: one for scenes with static backgrounds and the
other for scenes with dynamic (moving) backgrounds.


title:
Study of Network Migration to New Technologies using Agent-based
  Modeling Techniques

abstract:
  Conventionally, network migration models study competition between emerging
and incumbent technologies by considering the resulting increase in revenue and
associated cost of migration. We propose to advance the science in the existing
network migration models by considering additional critical factors, including
(i) synergistic relationships across multiple technologies, (ii) reduction in
operational expenditures (OpEx) as a reason to migrate, and, (iii) implications
of local network effects on migration decisions. To this end, we propose a
novel agent-based migration model considering these factors. Based on the
model, we analyze the case study of network migration to two emerging
networking paradigms, i.e., IETF Path Computation Element (PCE) and
Software-Defined Networking (SDN). We validate our model using extensive
simulations. Our results demonstrate the synergistic effects of migration to
multiple complementary technologies, and show that a technology migration may
be eased by the joint migration to multiple technologies. In particular, we
find that migration to SDN can be eased by joint migration to PCE, and that the
benefits derived from SDN are best exploited in combination with PCE, than by
itself.


title:
Identification of Signal, Noise, and Indistinguishable Subsets in
  High-Dimensional Data Analysis

abstract:
  Motivated by applications in high-dimensional data analysis where strong
signals often stand out easily and weak ones may be indistinguishable from the
noise, we develop a statistical framework to provide a novel categorization of
the data into the signal, noise, and indistinguishable subsets. The
three-subset categorization is especially relevant under high-dimensionality as
a large proportion of signals can be obscured by the large amount of noise.
Understanding the three-subset phenomenon is important for the researchers in
real applications to design efficient follow-up studies. %For example,
candidates belonging to the signal subset may have priority for more focused
study, while those in the noise subset can be removed; and, for candidates in
the indistinguishable subset, additional data may be collected to further
separate weak signals from the noise. We develop an efficient data-driven
procedure to identify the three subsets. Theoretical study shows that, under
certain conditions, only signals are included in the identified signal subset
while the remaining signals are included in the identified indistinguishable
subsets with high probability. Moreover, the proposed procedure adapts to the
unknown signal intensity, so that the identified indistinguishable subset
shrinks with the true indistinguishable subset when signals become stronger.
The procedure is examined and compared with methods based on FDR control using
Monte Carlo simulation. Further, it is applied successfully in a real-data
application to identify genomic variants having different signal intensity.


title:
Well-posedness for the Prandtl system without analyticity or
  monotonicity

abstract:
  It has been thought for a while that the Prandtl system is only well-posed
under the Oleinik monotonicity assumption or under an analyticity assumption.
We show that the Prandtl system is actually locally well-posed for data that
belong to the Gevrey class 7/4 in the horizontal variable x. Our result
improves the classical local well-posedness result for data that are analytic
in x (that is Gevrey class 1). The proof uses new estimates, based on
non-quadratic energy functionals.


title: The Arithmetic of Curves Defined by Iteration

abstract:
  We show how the size of the Galois groups of iterates of a quadratic
polynomial $f(x)$ can be parametrized by certain rational points on the curves
$C_n:y^2=f^n(x)$ and their quadratic twists. To that end, we study the
arithmetic of such curves over global and finite fields, translating key
problems in the arithmetic of polynomial iteration into a geometric framework.
This point of view has several dynamical applications. For instance, we
establish a maximality theorem for the Galois groups of the fourth iterate of
quadratic polynomials $x^2+c$, using techniques in the theory of rational
points on curves. Moreover, we show that the Hall-Lang conjecture on integral
points of elliptic curves implies a Serre-type finite index result for these
dynamical Galois groups, and we use conjectural bounds for the Mordell curves
to predict the index in the still unknown case when $f(x)=x^2+3$. Finally, we
provide evidence that these curves defined by iteration have geometrical
significance, as we construct a family of curves whose rational points we
completely determine and whose geometrically simple Jacobians have complex
multiplication and positive rank.


title:
Dimerization of Water Molecules. Modeling of the Attractive Part of the
  Interparticle Potential in the Multipole Approximation

abstract:
  The work presents the detailed analysis of the water dimer properties. Their
parameters are investigated on the basis of a multipole interaction potential
extended up to the quadrupole--quadrupole and dipole--octupole terms. All main
equilibrium parameters of the dimer are obtained: its geometry, ground-state
energy, dipole and quadrupole moments, vibration frequencies, {\it etc}. They
are thoroughly compared with those obtained in quantum chemical calculations
and from spectroscopic data. The efficiency of the present model potentials is
discussed. A new viewpoint on the nature of the hydrogen bond is presented. The
results of studies are thoroughly compared with the spectroscopic and computer
simulation data.


title: Latest results from XENON100 data

abstract:
  XENON100 is the current phase of the XENON dark matter program, which aims
for the direct detection of WIMPs with liquid xenon time-projection chambers.
We present the status of the experiment after 224.6 live days taken in 2011 and
2012 during which the detector successfully improved in terms of more
calibration data, higher xenon purity, lower threshold and better background
removal. The analysis has yielded no evidence for dark matter interactions. The
status of the next generation XENON1T detector will be briefly described.


title: A quantum non-Markovian collision model: incoherent swap case

abstract:
  We have recently presented a collision-model-based framework to approach
non-Markovian quantum dynamics [Ciccarello F Palma G M and Giovannetti V 2013
Phys. Rev. A 87, 040103(R)]. As a distinctive feature, memory is introduced in
a dynamical way by adding extra inter-ancillary collisions to a standard
(memoryless) collision model. Here, we focus on the case where such intra-bath
collisions are described by incoherent partial swap operations. After briefly
reviewing the model, we show how to include temperature as an additional
parameter by relaxing the assumption that each bath ancilla is initially in a
pure state. We also calculate explicitly the dynamical map entailed by the
master equation in the paradigmatic instance of a Jaynes-Cummings
system-ancilla coupling.


title:
Hardy's type inequality for the over critical exponent associated with
  the Dunkl transform

abstract:
  \begin{abstract} For the Hardy space $H^p(\mathbb{R}^{d})$, $ 0<p\leq 1,$ we
shall improve a Hardy's type inequality associated with Dunkl transform respect
to the measures $d\mu_{k}$ homogeneous of degree $\gamma ,$ on the strip
$(2\gamma+d)(2-p)\leq\sigma<2\gamma+d+p(N+1),$ where $N =[(2\gamma+d)(1/p-1)]$
is the greatest integer not exceeding $(2\gamma+d)(1/ p -1).$ \end{abstract}


title:
Hybrid Optoelectronic Correlator Architecture for Shift Invariant Target
  Recognition

abstract:
  In this paper, we present theoretical details and the underlying architecture
of a hybrid optoelectronic correlator that correlates images using Spatial
Light Modulators (SLM), detector arrays and Field Programmable Gate Array
(FPGA). The proposed architecture bypasses the need for nonlinear materials
such as photorefractive polymer films by using detectors instead, and the phase
information is yet conserved by the interference of plane waves with the
images. However, the output of such a Hybrid Opto-electronic Correlator (HOC)
has four terms: two convolution signals and two cross-correlation signals. By
implementing a phase stabilization and scanning circuit, the convolution terms
can be eliminated, so that the behavior of an HOC becomes essentially identical
to that of a conventional holographic correlator (CHC). To achieve the ultimate
speed of such a correlator, we also propose an opto-electronic chip which would
perform all the electrical processes in a parallel manner. The HOC architecture
along with the phase stabilization technique would thus be as good as a CHC,
capable of high speed image recognition in a translation invariant manner.


title: On the Sums of Inverse Even Powers of Zeros of Regular Bessel Functions

abstract:
  We provide a new, simple general proof of the formulas giving the infinite
sums $\sigma(p,\nu)$ of the inverse even powers $2p$ of the zeros $\xi_{\nu k}$
of the regular Bessel functions $J_{\nu}(\xi)$, as functions of $\nu$. We also
give and prove a general formula for certain linear combinations of these sums,
which can be used to derive the formulas for $\sigma(p,\nu)$ by purely
linear-algebraic means, in principle for arbitrarily large powers. We prove
that these sums are always given by a ratio of two polynomials on $\nu$, with
integer coefficients. We complete the set of known formulas for the smaller
values of $p$, extend it to $p=9$, and point out a connection with the Riemann
zeta function, which allows us to calculate some of its values.


title: Fluctuation-dissipation and equilibrium for scalar fields in de Sitter

abstract:
  The infrared dynamics of a minimally coupled scalar field in de Sitter
spacetime can be described as Brownian motion of a particle in a medium of de
Sitter temperature $T_{DS}=\frac{H}{2\pi}$. The system obeys a
fluctuation-dissipation relation and its equilibrium distribution is
Maxwell-Boltzmann, implying kinetic and potential energies of comparable
magnitudes. The transition to equilibrium is a semi-classical process beyond
the scope of perturbation theory for interacting fields. The stochastic kinetic
energy of the field causes de Sitter spacetime to cool down slowly with a
corresponding decrease of the effective vacuum energy.


title: Symplectic embeddings of 4-dimensional ellipsoids: erratum

abstract:
  This note describes a correct way to perform the inflation procedures claimed
in the papers on embedding ellipsoids, Journ. Top. 2 (2009), 1-22 and 589-623.
The idea is to inflate along a collection of transversally and positively
intersecting symplectic surfaces (as in Li--Usher (JSG 2006)) rather than along
a single embedded surface.


title: Hodge metric completion of the moduli space of Calabi-Yau manifolds

abstract:
  In this paper, it is proved that the Hodge metric completion of the moduli
space of polarized and marked Calabi-Yau manifolds, i.e. the Torelli space, is
a complex affine manifold. As applications we prove that the period map from
the Torelli space and the extended period map from its completion space, both
are injective into the period domain, and that the completion space is a
bounded domain of holomorphy with a complete K\"ahler-Einstein metric. As a
corollary we show that the period map from the moduli space of polarized
Calabi-Yau manifolds with level $m$ structure is also injective.


title: Radiation fields in star-forming galaxies: the disk, thin disk and bulge

abstract:
  We provide and describe a library of diffuse stellar radiation fields in
spiral galaxies derived using calculations of the transfer of stellar radiation
from the main morphological components - disks, thin disks, and bulges -
through the dusty interstellar medium. These radiation fields are
self-consistent with the solutions for the integrated panchromatic spectral
energy distributions (SEDs) previously presented using the same model. Because
of this, observables calculated from the radiation fields, such as gamma-ray or
radio emission, can be self-consistently combined with the solutions for the
ultraviolet/optical/submillimeter SEDs, thus expanding the range of
applicability of the radiation transfer model to a broader range of wavelengths
and physical quantities. We also give analytic solutions for radiation fields
in optically thin stellar disks, in stellar disks with one dust disk and in
stellar disks with two dust disks. The analytic solutions for the direct light
are exact and can be used as benchmarks. The analytic solutions with scattering
are only approximate, becoming exact only in the extreme optically thick limit.
We find strongly contrasting solutions for the spatial distribution of the
radiation fields for disks, thin disks and bulges. For bulges we find a strong
dependence of the radiation fields on Sersic index.


title:
Effects of Plasma Drag on Low Earth Orbiting Satellites due to Heating
  of Earth's Atmosphere by Coronal Mass Ejections

abstract:
  Solar events, such as coronal mass ejections (CMEs) and solar flares, heat up
the upper atmosphere and near-Earth space environment. Due to this heating and
expansion of the outer atmosphere by the energetic ultraviolet, X-ray and
particles expelled from the sun, the low Earth-Orbiting satellites (LEOS)
become vulnerable to an enhanced drag force by the ions and molecules of the
expanded atmosphere. Out of various types of perturbations, Earth directed CMEs
play the most significant role. They are more frequent and intense during the
active (solar maximum) phase of the sun's approximately 11-year cycle. As we
are approaching another solar maximum later in 2013, it may be instructive to
analyse the effects of the past solar cycles on the orbiting satellites using
the archival data of space environment parameters as indicators. In this paper,
we compute the plasma drag on a model LEOS due to the atmospheric heating by
CMEs and other solar events as a function of the solar parameters. Using the
current forecast on the time and strength of the next solar maximum, we predict
how an existing satellite orbit may be affected in the forthcoming years.


title: Dedicated Indirect Searches for Dark Matter Using Antideuterons

abstract:
  This white paper describes the basic idea for indirect dark matter searches
using antideuterons. Low energy antideuterons produced by dark matter
annihilations/decays provide an attractive dark matter signature, due to the
low astrophysical background. The current and future experiments have a strong
potential to detect antideuterons from dark matter. They are complementary not
only with each other, but also with other dark matter searches.


title:
Millimetre-Wave and Near-Infrared Signposts of Massive Molecular Clump
  Evolution and Star Cluster Formation

abstract:
  We report new near-infrared and mm-wave observational data on a selection of
massive Galactic molecular clumps (part of the CHaMP sample) and their
associated young star clusters. The clumps show, for the first time in a "dense
gas tracer", a significant correlation between HCO+ line emission from cold
molecular gas and Br{\gamma} line emission of associated nebulae. This
correlation arises in the HCO+ line's brightness, not its linewidth. In
contrast, the correlation between the N2H+ line emission and Br{\gamma} is weak
or absent. The HCO+/N2H+ line ratio also varies widely from clump to clump:
bright HCO+ emission tends to be more closely associated with Br{\gamma}
nebulosity, while bright N2H+ emission tends to avoid areas that are bright in
Br{\gamma}. Both molecular species show correlations of weak significance with
infrared H2 v=1-0 and v=2-1 line emission, in or near the clumps. The H2
emission line ratio is consistent with fluorescent excitation in most of the
clumps, although thermal excitation is seen in a few clumps. We interpret these
trends as evidence for evolution in the gas conditions due to the effects of
ongoing star formation in the clumps, in particular, the importance of UV
radiation from massive YSOs as the driving agent that heats the molecular gas
and alters its chemistry. This suggests that some traditional dense gas tracers
of molecular clouds do not sample a homogeneous population of clumps, i.e.,
that the HCO+ brightness in particular is directly related to the heating and
disruption of cold gas by massive young stars, whereas the N2H+ better samples
gas not yet affected by this process. We therefore suggest that the
HCO+-N2H+-Br{\gamma} relationship is a useful diagnostic of a molecular clump's
progress in forming massive stars.


title: Massive gravity: a General Analysis

abstract:
  Massive gravity can be described by adding to the Einstein-Hilbert action a
function V of metric components. By using the Hamiltonian canonical analysis,
we find the most general form of V such that five degrees of freedom propagate
non perturbatively. The construction is based on a set of differential
equations for $V$, that remarkably can be solved in terms of two arbitrary
functions. Besides recovering the known "Lorentz invariant" massive gravity
theory, we find an entirely new class of solutions, with healthy features on
the phenomenological side, in particular they are weakly coupled in the solar
system and have a high ultraviolet cutoff Lambda_2=(m M_pl)^(1/2), where m is
the graviton mass scale.


title: micrOMEGAs3.1 : a program for calculating dark matter observables

abstract:
  micrOMEGAs is a code to compute dark matter observables in generic extensions
of the standard model. This new version of micrOMEGAs is a major update which
includes a generalization of the Boltzmann equations to accommodate models with
asymmetric dark matter or with semi-annihilation and a first approach to a
generalization of the thermodynamics of the Universe in the relic density
computation. Furthermore a switch to include virtual vector bosons in the final
states in the annihilation cross sections or relic density computations is
added. Effective operators to describe loop-induced couplings of Higgses to
two-photons or two-gluons are introduced and reduced couplings of the Higgs are
provided allowing for a direct comparison with recent LHC results. A module
that computes the signature of DM captured in celestial bodies in neutrino
telescopes is also provided. Moreover the direct detection module has been
improved as concerns the implementation of the strange "content" of the
nucleon. New extensions of the standard model are included in the distribution.


title: FIT-MART: Quantum Magnetism with a Gentle Learning Curve

abstract:
  We present a new open-source software package, FIT-MART, that allows
non-experts to quickly get started simulating quantum magnetism. FIT-MART can
be downloaded as a platform-idependent executable Java (JAR) file. It allows
the user to define (Heisenberg) Hamiltonians by electronically drawing pictures
that represent quantum spins and operators. Sliders are automatically generated
to control the values of the parameters in the model, and when the values
change, several plots are updated in real time to display both the resulting
energy spectra and the equilibruim magnetic properties. Several experimental
data sets for real magnetic molecules are included in FIT-MART to allow easy
comparison between simulated and experimental data, and FIT-MART users can also
import their own data for analysis and compare the goodness of fit for
different models.


title:
Uncovering the network structure of the world currency market:
  Cross-correlations in the fluctuations of daily exchange rates

abstract:
  The cross-correlations between the exchange rate fluctuations of 74
currencies over the period 1995-2012 are analyzed in this paper. The eigenvalue
distribution of the cross-correlation matrix exhibits a bulk which
approximately matches the bounds predicted from random matrices constructed
using mutually uncorrelated time-series. However, a few large eigenvalues
deviating from the bulk contain important information about the global market
mode as well as important clusters of strongly interacting currencies.We
reconstruct the network structure of the world currency market by using two
different graph representation techniques, after filtering out the effects of
global or market-wide signals on the one hand and random effects on the other.
The two networks reveal complementary insights about the major motive forces of
the global economy, including the identification of a group of potentially fast
growing economies whose development trajectory may affect the global economy in
the future as profoundly as the rise of India and China has affected it in the
past decades.


title:
Ab initio calculations of phonon spectra in ATiO3 perovskite crystals (A
  = Ca, Sr, Ba, Ra, Cd, Zn, Mg, Ge, Sn, Pb)

abstract:
  The phonon spectra of calcium, strontium, barium, radium, cadmium, zinc,
magnesium, germanium, tin, and lead titanates with the perovskite structure are
calculated from first principles within the density functional theory. By
analyzing the unstable modes in the phonon spectra, the possible lattice
distortions are determined and the energies of the corresponding phases are
calculated. From analyzing the phonon spectra, force constants, and
eigenvectors of TO phonons, a conclusion is drawn on the origin of the
ferroelectricity in considered crystals. It is shown that the main factors
determining the possible off-centering of atoms in the A position are the
geometric size and electronic configuration of these atoms.


title: Limit laws for occupation times of stable processes

abstract:
  We prove two limit laws for functionals of one dimensional symmetric 1-stable
process using the method of moments, and give a remark on Rosen's paper
\cite{Rosen}.


title:
Multifractality and quantum-to-classical crossover in the Coulomb
  anomaly at the Mott-Anderson metal-insulator transition

abstract:
  We study the interaction driven localization transition, which a recent
experiment in Ga_{1-x}Mn_xAs As has shown to come along with multifractal
behavior of the local density of states (LDoS) and the intriguing persistence
of critical correlations close to the Fermi level. We show that the bulk of
these phenomena can be understood within a Hartree-Fock treatment of
disordered, Coulomb-interacting spinless fermions. A scaling analysis of the
LDoS correlation demonstrates multifractality with correlation dimension
d_2=1.57, which is significantly larger than at a non-interacting Anderson
transition. At the interaction-driven transition the states at the Fermi level
become critical, while the bulk of the spectrum remains delocalized up to
substantially stronger interactions. The mobility edge stays close to the Fermi
energy in a wide range of disorder strength, as the interaction strength is
further increased. The localization transition is concomitant with the
quantum-to-classical crossover in the shape of the pseudo-gap in the tunneling
density of states, and with the proliferation of metastable HF solutions that
suggest the onset of a glassy regime with poor screening properties.


title:
Convexity of the image of a quadratic map via the relative entropy
  distance

abstract:
  Let psi: R^n --> R^k be a map defined by k positive definite quadratic forms
on R^n. We prove that the relative entropy (Kullback-Leibler) distance from the
convex hull of the image of psi to the image of psi is bounded above by an
absolute constant. More precisely, we prove that for every point a=(a_1, ...,
a_k) in the convex hull of the image of psi such that a_1 + ... +a_k =1 there
is a point b=(b_1, ..., b_k) in the image of psi such that b_1 + ... + b_k =1
and such that a_1 ln(a_1/b_1) + ... + a_k ln(a_k/b_k) < 4.8. Similarly, we
prove that for any integer m one can choose a convex combination b of at most m
points from the image of psi such that a_1 ln(a_1/b_1) + ... + a_k ln(a_k/b_k)
< 15/sqrt{m}.


title:
QCD Sum-Rule Interpretation of X(3872) with $J^{PC}=1^{++}$ Mixtures of
  Hybrid Charmonium and $\bar D D^*$ Molecular Currents

abstract:
  QCD sum-rules are employed to determine whether the X(3872) can be described
as a mixed state that couples to $J^{PC}=1^{++}$ charmonium hybrid and $\bar D
D^*$ molecular currents. After calculating the mixed correlator of hybrid and
molecular currents, we formulate the sum-rule in terms of a mixing parameter
that interpolates between the pure molecular and hybrid scenarios. As the
mixing parameter is increased from the pure molecular case, the predicted mass
increases until it reaches a maximum value in good agreement with the X(3872)
and the resulting sum-rule analysis appears more robust than the pure molecular
case.


title: Automated generation of web server fingerprints

abstract:
  In this paper, we demonstrate that it is possible to automatically generate
fingerprints for various web server types using multifactor Bayesian inference
on randomly selected servers on the Internet, without building an a priori
catalog of server features or behaviors. This makes it possible to conclusively
study web server distribution without relying on reported (and variable)
version strings. We gather data by sending a collection of specialized requests
to 110,000 live web servers. Using only the server response codes, we then
train an algorithm to successfully predict server types independently of the
server version string. In the process, we note several distinguishing features
of current web infrastructure.


title: The minimal displacement and extremal spaces

abstract:
  We show that both separable preduals of $L_{1}$ and non-type I $C^*$-algebras
are strictly extremal with respect to the minimal displacement of $k$-Lipschitz
mappings acting on the unit ball of a Banach space. In particular, every
separable $C(K)$ space is strictly extremal.


abstract:
  The promotion work 'The Estimation of Transport Logistic Processes Models on
the Base of Intensive Computer Methods of Statistics' has been worked out by
Helen Afanasyeva to obtain the scientific degree of 'Doctor of Science
Engineering in Telematics and Logistics'. Scientific supervisor of the work is
Dr.habil.sc.ing., professor Alexander Andronov. The work is devoted to the
implementation of the modern statistical methods for the transport and logistic
models analysis. The intensive computer method resampling is especially
attended. This method is non-parametrical and gives the most efficient
estimators of the systems' characteristics in the case of small initial sample
sizes. The investigation was held in three main directions: the forecasting and
estimation of logistic models, the estimation of the reliability and efficiency
of carries, and the analysis of inventory control problems in logistic systems.
Resampling method usage algorithms and inferences for formulas of the
efficiency comparison of traditional and resampling approaches were suggested
for each task implementing corresponding mathematical model. The efficiency
criteria were: bias, variance or mean squared error of the estimator. The
numerical results proving the efficiency of the suggested approach were
obtained. The conclusions and recommendations, concerning the conditions in
which the suggested approach is the most effective were made. The obtained
results are general, because can be used in other subject areas.


title: Is \theta_{13}^{PMNS} correlated with \theta_{23}^{PMNS} or not?

abstract:
  By postulating the relation \theta_{23} \simeq 45^\circ + \eta\theta_{13}, we
seek preferable correction terms to tri-bi-maximal mixing and discuss their
origins. Global analyses of the neutrino oscillation parameters favor \eta=\pm
1/\sqrt{2}; this corresponds to the relation found by Edy, Frampton, and
Matsuzaki some years ago in the context of a T^\prime flavor symmetry. In
contrast, the results of the \nu_\mu disappearance mode reported by the T2K and
Super-Kamiokande collaborations seem to prefer \eta=0, which gives an almost
maximal \theta_{23}. We derive a general condition for ensuring \theta_{23}
\simeq 45^\circ + \eta\theta_{13} and find that the condition is complicated by
the neutrino masses and CP violating phases. We investigate the condition under
simplified environments and arrive at several correction terms to the mass
matrices. It is found that the obtained correction terms can arise from flavor
symmetries or one-loop radiative corrections.


title:
Triggering Collapse of the Presolar Dense Cloud Core and Injecting
  Short-Lived Radioisotopes with a Shock Wave. II. Varied Shock Wave and Cloud
  Core Parameters

abstract:
  A variety of stellar sources have been proposed for the origin of the
short-lived radioisotopes that existed at the time of the formation of the
earliest Solar System solids, including Type II supernovae, AGB and super-AGB
stars, and Wolf-Rayet star winds. Our previous adaptive mesh hydrodynamics
models with the FLASH2.5 code have shown which combinations of shock wave
parameters are able to simultaneously trigger the gravitational collapse of a
target dense cloud core and inject significant amounts of shock wave gas and
dust, showing that thin supernova shocks may be uniquely suited for the task.
However, recent meteoritical studies have weakened the case for a direct
supernova injection to the presolar cloud, motivating us to re-examine a wider
range of shock wave and cloud core parameters, including rotation, in order to
better estimate the injection efficiencies for a variety of stellar sources. We
find that supernova shocks remain as the most promising stellar source, though
planetary nebulae resulting from AGB star evolution cannot be conclusively
ruled out. Wolf-Rayet star winds, however, are likely to lead to cloud core
shredding, rather than to collapse. Injection efficiencies can be increased
when the cloud is rotating about an axis aligned with the direction of the
shock wave, by as much as a factor of $\sim 10$. The amount of gas and dust
accreted from the post-shock wind can exceed that injected from the shock wave,
with implications for the isotopic abundances expected for a supernova source.


title: Level densities of nickel isotopes: microscopic theory versus experiment

abstract:
  We apply a spin-projection method to calculate microscopically the level
densities of a family of nickel isotopes $^{59-64}$Ni using the shell model
Monte Carlo approach in the complete $pfg_{9/2}$ shell. Accurate ground-state
energies of the odd-mass nickel isotopes, required for the determination of
excitation energies, are determined using the Green's function method recently
introduced to circumvent the odd particle-number sign problem. Our results are
in excellent agreement with recent measurements based on proton evaporation
spectra and with level counting data at low excitation energies. We also
compare our results with neutron resonance data, assuming equilibration of
parity and a spin-cutoff model for the spin distribution at the neutron binding
energy, and find good agreement with the exception of $^{63}$Ni.


title: Gravitational Interaction of Higgs Boson and Weak Boson Scattering

abstract:
  With the LHC discovery of a 125 GeV Higgs-like boson, we study gravitational
interaction of the Higgs boson via the unique dimension-4 operator involving
Higgs doublet and scalar curvature, $\,\xi H^\dag H R\,$, with nonminimal
coupling $\,\xi\,$. This Higgs portal term can be transformed away in Einstein
frame and induces gauge-invariant effective interactions in the Higgs sector.
We study the weak boson scattering in Einstein frame, and explicitly
demonstrate the longitudinal-Goldstone boson equivalence theorem in the
presence of $\,\xi\,$ coupling. With these, we derive unitarity bound on the
Higgs gravitational coupling $\,\xi\,$ in Einstein frame, which is stronger
than that inferred from the current LHC Higgs measurements. We further study
$\xi$-dependent weak boson scattering cross sections at TeV scale, and propose
a new LHC probe of the Higgs-gravity coupling $\,\xi\,$ via weak boson
scattering experiments.


title: The hunt for axionlike particles with the Cherenkov Telescope Array

abstract:
  Gamma-ray photons can convert into axion-like particles (ALPs) and vice versa
when interacting with astrophysical magnetic fields. The conversions of ALPs
may have important implications for astrophysics since they would imprint
characteristic features on the spectra of gamma-ray sources. The features may
be detected by the Fermi Gamma-ray Space Telescope and by current Imaging
Atmospheric Cherenkov Telescopes (IACTs) or the future Cherenkov Telescope
Array (CTA). Thus, gamma-ray observations can provide valuable constraints on
the nature of ALPs, and represent an excellent complementary approach to
laboratory searches for ALPs. CTA's twenty times larger collection area and
improved sensitivity compared to current IACTs will make it an extraordinarily
powerful instrument to search for signatures of ALPs imprinted in the spectra
of gamma-ray sources in the energy range between a few tens of GeV up to a few
dozen TeV. The US contribution of Medium Size Telescopes will be therefore
particularly important for ALP searches, as it will improve the sensitivity of
the core energy regime (100 GeV - 10 TeV) of CTA by a factor of 2-3. As
photon/ALP conversions are used as the main vehicle in the search, rather than
the usual self-annihilations for WIMP candidates, the unknown dark matter
nature will be scrutinized from a different perspective. Indeed, CTA could
probe a region of the ALP parameter space in which ALPs might account for the
total cold dark matter content in the Universe.


title:
Gamma-ray Signatures of Ultra High Energy Cosmic Ray Line-of-sight
  Interactions

abstract:
  Ultra High Energy Cosmic Rays (UHECRs) interact en route to Earth, producing
secondary gamma-rays. For the case of high cosmic ray power and weak
intergalactic magnetic fields, the deflections of these UHECRs may be small
leading to detectable gamma-ray fluxes that point back to their origin. We
summarize current results and prospects of detecting a signature of these
interactions using the current and next generation of imaging atmospheric
Cherenkov telescopes.


title: The shape of multidimensional Brunet--Derrida particle systems

abstract:
  We introduce particle systems in one or more dimensions in which particles
perform branching Brownian motion and the population size is kept constant
equal to $N > 1$, through the following selection mechanism: at all times only
the $N$ fittest particles survive, while all the other particles are removed.
Fitness is measured with respect to some given score function $s:\R^d \to \R$.
For some choices of the function $s$, it is proved that the cloud of particles
travels at positive speed in some possibly random direction. In the case where
$s$ is linear, we show under some assumptions on the initial configuration that
the shape of the cloud scales like $\log N$ in the direction parallel to motion
but at least $c(\log N)^{3/2}$ in the orthogonal direction for some $c > 0$. We
conjecture that the exponent 3/2 is sharp. This result is equivalent to the
following result of independent interest: in one-dimensional systems, the
genealogical time is greater than $c(\log N)^3$, thereby contributing a step
towards the original predictions of Brunet and Derrida. We discuss several open
problems and also explain how our results can be viewed as a rigorous
justification of Weismann's arguments for the role of recombination in
population genetics.


title: Bessel Functions, Heat Kernel and the Conical K\"ahler-Ricci Flow

abstract:
  Following Donaldson's oppenness theorem on deforming a conical
K\"ahler-Einstein metric, we prove a parabolic Schauder-type estimate with
respect to conical metrics. As a corollary, we show that the conical
K\"ahler-Ricci Flow exists for short time. The key is to establish the relevant
heat kernel estimates, where we use the Weber's formula on Bessel function of
the second kind and Carslaw's heat kernel representation in \cite{Car}.


title:
Master equation for the Unruh-DeWitt detector and the universal
  relaxation time in de Sitter space

abstract:
  We derive the master equation that completely determines the time evolution
of the density matrix of the Unruh-DeWitt detector in an arbitrary background
geometry. We apply the equation to reveal a nonequilibrium thermodynamic
character of de Sitter space. This generalizes an earlier study on the
thermodynamic property of the Bunch-Davies vacuum that an Unruh-DeWitt detector
staying in the Poincare patch and interacting with a scalar field in the
Bunch-Davies vacuum behaves as if it is in a thermal bath of finite
temperature. In this paper, instead of the Bunch-Davies vacuum, we consider a
class of initial states of scalar field, for which the detector behaves as if
it is in a medium that is not in thermodynamic equilibrium and that undergoes a
relaxation to the equilibrium corresponding to the Bunch-Davies vacuum. We give
a prescription for calculating the relaxation times of the nonequilibrium
processes. We particularly show that, when the initial state of the scalar
field is the instantaneous ground state at a finite past, the relaxation time
is always given by a universal value of half the curvature radius of de Sitter
space. We expect that the relaxation time gives a nonequilibrium thermodynamic
quantity intrinsic to de Sitter space.


title:
Non-Positive Partial Transpose Subspaces Can be as Large as Any
  Entangled Subspace

abstract:
  It is known that, in an $(m \otimes n)$-dimensional quantum system, the
maximum dimension of a subspace that contains only entangled states is
(m-1)(n-1). We show that the exact same bound is tight if we require the
stronger condition that every state with range in the subspace has non-positive
partial transpose. As an immediate corollary of our result, we solve an open
question that asks for the maximum number of negative eigenvalues of the
partial transpose of a quantum state. In particular, we give an explicit method
of construction of a bipartite state whose partial transpose has (m-1)(n-1)
negative eigenvalues, which is necessarily maximal, despite recent numerical
evidence that suggested such states may not exist for large m and n.


title:
Inverting Nonlinear Dimensionality Reduction with Scale-Free Radial
  Basis Function Interpolation

abstract:
  Nonlinear dimensionality reduction embeddings computed from datasets do not
provide a mechanism to compute the inverse map. In this paper, we address the
problem of computing a stable inverse map to such a general bi-Lipschitz map.
Our approach relies on radial basis functions (RBFs) to interpolate the inverse
map everywhere on the low-dimensional image of the forward map. We demonstrate
that the scale-free cubic RBF kernel performs better than the Gaussian kernel:
it does not suffer from ill-conditioning, and does not require the choice of a
scale. The proposed construction is shown to be similar to the Nystr\"om
extension of the eigenvectors of the symmetric normalized graph Laplacian
matrix. Based on this observation, we provide a new interpretation of the
Nystr\"om extension with suggestions for improvement.


title: A Thousand Problems in Cosmology. Chapter 4: Black holes

abstract:
  The fourth chapter of the collection of problems in cosmology, devoted to
black holes. Consists of basic introduction, sections on Schwarzschild and Kerr
black holes, a section on particles' motion and collisions in general black
hole space-times, and the astrophysical part. This version contains only
formulations of 137 problems. The full collection, with solutions included, is
available in the form of a wiki-based resource at www.universeinproblems.com.
The cosmological community is welcome to contribute to its development.

categories: physics.ed-ph astro-ph.CO gr-qc physics.pop-ph


title: The M-basis Problem for Separable Banach Spaces

abstract:
  In this note we show that, if $\mcB$ is separable Banach space, then there is
a biorthogonal system $\{x_n, x_n^*\}$ such that, the closed linear span of
$\{x_n\},\bar{\left\langle {\{x_n\}}\right\rangle}=\mcB$ and $\left\| {x_n}
\right\|\left\| {x_n^*} \right\| = 1$ for all $n$.


title: Web Services Dependency Networks Analysis

abstract:
  Along with a continuously growing number of publicly available Web services
(WS), we are witnessing a rapid development in semantic-related web
technologies, which lead to the apparition of semantically described WS. In
this work, we perform a comparative analysis of the syntactic and semantic
approaches used to describe WS, from a complex network perspective. First, we
extract syntactic and semantic WS dependency networks from a collection of
publicly available WS descriptions. Then, we take advantage of tools from the
complex network field to analyze them and determine their topological
properties. We show WS dependency networks exhibit some of the typical
characteristics observed in real-world networks, such as small world and scale
free properties, as well as community structure. By comparing syntactic and
semantic networks through their topological properties, we show the
introduction of semantics in WS description allows modeling more accurately the
dependencies between parameters, which in turn could lead to improved
composition mining methods.


title:
On-sky characterisation of the VISTA NB118 narrow-band filters at 1.19
  micron

abstract:
  Observations of the high redshift Universe through narrow-band filters have
proven very successful in the last decade. The 4-meter VISTA telescope,
equipped with the wide-field camera VIRCAM, offers a major step forward in
wide-field near-infrared imaging, and in order to utilise VISTA's large
field-of-view and sensitivity, the Dark Cosmology Centre provided a set of 16
narrow-band filters for VIRCAM. These NB118 filters are centered at a
wavelength near 1.19 micron in a region with few airglow emission lines. The
filters allow the detection of Halpha emitters at z = 0.8, Hbeta and [OIII]
emitters at z ~ 1.4, [OII] emitters at z = 2.2, and Ly-alpha emitters at z =
8.8. Based on guaranteed time observations of the COSMOS field we here present
a detailed description and characterization of the filters and their
performance. In particular we provide sky-brightness levels and depths for each
of the 16 detector/filter sets and find that some of the filters show signs of
some red-leak. We identify a sample of 2 x 10^3 candidate emission-line objects
in the data. Cross-correlating this sample with a large set of galaxies with
known spectroscopic redshifts we determine the "in situ" passbands of the
filters and find that they are shifted by about 3.5-4 nm (corresponding to 30%
of the filter width) to the red compared to the expectation based on the
laboratory measurements. Finally, we present an algorithm to mask out
persistence in VIRCAM data. Scientific results extracted from the data will be
presented separately.