title:
On-chip interference of single photons from an embedded quantum dot and
  an external laser

abstract:
  In this work, we demonstrate the on-chip two-photon interference between
single photons emitted by a single self-assembled InGaAs quantum dot and an
external laser. The quantum dot is embedded within one arm of an air-clad
directional coupler which acts as a beam-splitter for incoming light. Photons
originating from an attenuated external laser are coupled to the second arm of
the beam-splitter and then combined with the quantum dot photons, giving rise
to two-photon quantum interference between dissimilar sources. We verify the
occurrence of on-chip Hong-Ou-Mandel interference by cross-correlating the
optical signal from the separate output ports of the directional coupler. This
experimental approach allows us to use classical light source (laser) to assess
in a single step the overall device performance in the quantum regime and probe
quantum dot photon indistinguishability on application realistic time scales.


title:
The BL-Lac gamma-ray blazar PKS 1424+240 associated with a group of
  galaxies at z=0.6010

abstract:
  PKS 1424+240 is a BL-Lac blazar with unknown redshift that was detected at
high-energy gamma rays by Fermi-LAT with a hard spectrum. At VHE, it was first
detected by VERITAS and later confirmed by MAGIC. Its spectral energy
distribution is highly attenuated at VHE gamma rays, which is coherent with
distant sources. Several estimations enabled the redshift to be constrained to
the range 0.6 < z < 1.3. These results place PKS 1424+240 in the very
interesting condition of being probably the most distant blazar that has been
detected at VHE. The ambiguity in the redshift is still large enough to prevent
precise studies of the EBL and the intrinsic blazar spectrum. Given the
difficulty of measuring spectroscopic redshifts for BL-Lac objects directly, we
aim to establish a reliable redshift value for this blazar by finding its host
group of galaxies. Elliptical galaxies are associated with groups, and BL-Lac
objects are typically hosted by them, so we decided to search for the host
group of the blazar. For this, we performed optical spectroscopic observations
of thirty objects in the field of view of PKS 1424+240 using the Gemini MOS.
After analysing the data for groups, we evaluated the probability of finding
groups of galaxies by chance around the position of PKS 1424+240, using a deep
catalogue of groups. We also used photometric data from the SDSS catalogue to
analyse the red sequence of the proposed blazar host group. We found a new
group of galaxies with eight members at z = 0.6010 +- 0.003, a virial radius of
R_vir = 1.53 Mpc, and a velocity dispersion of sigma_v = 813 +- 187 km/s. The
photometric study indicates that more members are probably populating this
previously uncatalogued group of galaxies. The probability of PKS 1424+240
being a member of this group was found to be 98%. The new group of galaxies
found at z = 0.6010 +- 0.003 is very likely hosting PKS 1424+240.


title: Discrete Polynomial Blending

abstract:
  In this paper we study "discrete polynomial blending," a term used to define
a certain discretized version of curve blending whereby one approximates from
the "sum of tensor product polynomial spaces" over certain grids. Our strategy
is to combine the theory of Boolean Sum methods with dual bases connected to
the Bernstein basis to construct a new quasi-interpolant for discrete blending.
Our blended element has geometric properties similar to that of the
Bernstein-B\'ezier tensor product surface patch, and rates of approximation
that are comparable with those obtained in tensor product polynomial
approximation.


title: Black Hole Field Theory with a Firewall in two spacetime dimensions

abstract:
  We propose that the vacuum state of a scalar field around a black hole is a
modified Unruh vacuum. In (1+1) dimensions, we show that a free-faller close to
such an horizon can be modelled as an inertial observer in a modified Minkowski
vacuum. The modification allows for information-leaking correlations at high
frequencies. Using a Gaussian detector centred at $k_0$, we find that the
expectation value of the number operator for a detector crossing the horizon is
proportional to $1/|k_0|$, implying that the free-faller will observe unbounded
numbers of high energy photons, i.e. a firewall.


title: Laplacian flow of homogeneous G2-structures and its solitons

abstract:
  We use the bracket flow/algebraic soliton approach to study the Laplacian
flow of $G_2$-structures and its solitons in the homogeneous case. We prove
that any homogeneous Laplacian soliton is equivalent to a semi-algebraic
soliton (i.e.\ a $G$-invariant $G_2$-structure on a homogeneous space $G/K$
that flows by pull-back of automorphisms of $G$ up to scaling). Algebraic
solitons are geometrically characterized among Laplacian solitons as those with
a `diagonal' evolution. Unlike the Ricci flow case, where any homogeneous Ricci
soliton is isometric to an algebraic soliton, we have found, as an application
of the above characterization, an example of a left-invariant closed
semi-algebraic soliton on a nilpotent Lie group which is not equivalent to any
algebraic soliton. The (normalized) bracket flow evolution of such a soliton is
periodic. In the context of solvable Lie groups with a codimension-one abelian
normal subgroup, we obtain long time existence for any closed Laplacian flow
solution; furthermore, the norm of the torsion is strictly decreasing and
converges to zero. We also classify algebraic solitons in this class and
exhibit several explicit examples of closed expanding Laplacian solitons.


title:
Coupled networks and networks with bimodal frequency distributions are
  equivalent

abstract:
  Populations of oscillators can display a variety of synchronization patterns
depending on the oscillators' intrinsic coupling and the coupling between them.
We consider two coupled, symmetric (sub)populations with unimodal frequency
distributions and show that the resulting synchronization patterns may resemble
those of a single population with bimodally distributed frequencies. Our proof
of the equivalence of their stability, dynamics, and bifurcations, is based on
an Ott-Antonsen ansatz. The generalization to networks consisting of multiple
(sub)populations vis-\`a-vis networks with multimodal frequency distributions,
however, appears impossible.


title: Approximation Complexity of Max-Cut on Power Law Graphs

abstract:
  In this paper we study the MAX-CUT problem on power law graphs (PLGs) with
power law exponent $\beta$. We prove some new approximability results on that
problem. In particular we show that there exist polynomial time approximation
schemes (PTAS) for MAX-CUT on PLGs for the power law exponent $\beta$ in the
interval $(0,2)$. For $\beta>2$ we show that for some $\epsilon>0$, MAX-CUT is
NP-hard to approximate within approximation ratio $1+\epsilon$, ruling out the
existence of a PTAS in this case. Moreover we give an approximation algorithm
with improved constant approximation ratio for the case of $\beta>2$.


title:
Pseudodifferential Calculus, Twisted gerbes and twisted index theory for
  Lie groupoids

abstract:
  The goal of this paper is to construct a calculus whose higher indices are
naturally elements in the twisted K-theory groups for Lie groupoids. Given a
Lie groupoid $G$ and a $PU(H)$-valued groupoid cocycle, we construct an algebra
of projective pseudodifferential operators. The subalgebra of regularizing
operators identifies with the naturally associated smooth convolution algebra
of the associated twisted gerbe. We develop the associated symbolic calculus,
symbol short exact sequences and existence of parametrices. In particular the
algebra of projective operators appears as a quantization of the twisted symbol
algebra. As the (untwisted) Lie groupoid case that it encompasses, the negative
order operators extend to the twisted $C^*$-algebra and the zero order
operators act as bounded multipliers on it. We obtain an analytic index
morphism in twisted K-theory associated in a classic way by the corresponding
pseudodifferential extension. We prove that this index morphism only depends on
the isomorphism class of the cocycle, {\it i.e.,} on the twisting as the
associated class in $H^1(G;PU(H))$. We also show that this twisted analytic
index morphism is compatible with the index we constructed in a previous work,
in collaboration with Bai-Ling Wang, by means of the Connes tangent groupoid,
obtaining as a consequence the analytic interpretation, in terms of projective
pseudodifferential operators and ellipticity, of the twisted longitudinal
Connes-Skandalis index theorem. Our construction encompasses and unifies
several previous cases treated in the literature, we discuss in the final
section some examples of classes of operators unified by our setting.


title: Graph Isomorphism for unit square graphs

abstract:
  In the past decades for more and more graph classes the Graph Isomorphism
Problem was shown to be solvable in polynomial time. An interesting family of
graph classes arises from intersection graphs of geometric objects. In this
work we show that the Graph Isomorphism Problem for unit square graphs,
intersection graphs of axis-parallel unit squares in the plane, can be solved
in polynomial time. Since the recognition problem for this class of graphs is
NP-hard we can not rely on standard techniques for geometric graphs based on
constructing a canonical realization. Instead, we develop new techniques which
combine structural insights into the class of unit square graphs with
understanding of the automorphism group of such graphs. For the latter we
introduce a generalization of bounded degree graphs which is used to capture
the main structure of unit square graphs. Using group theoretic algorithms we
obtain sufficient information to solve the isomorphism problem for unit square
graphs.


title:
Explicit Conditions on Existence and Uniqueness of Load-Flow Solutions
  in Distribution Networks

abstract:
  We present explicit sufficient conditions that guarantee the existence and
uniqueness of the feasible load-flow solution for distribution networks with a
generic topology (radial or meshed) modeled with positive sequence equivalents.
In the problem, we also account for the presence of shunt elements. The
conditions have low computational complexity and thus can be efficiently
verified in a real system. Once the conditions are satisfied, the unique
load-flow solution can be reached by a given fixed point iteration method of
approximately linear complexity. Therefore, the proposed approach is of
particular interest for modern active distribution network (ADN) setup in the
context of real-time control. The theory has been confirmed through numerical
experiments.


title:
Redshift and luminosity evolution of the intrinsic alignments of
  galaxies in Horizon-AGN

abstract:
  Intrinsic galaxy shape and angular momentum alignments can arise in
cosmological large-scale structure due to tidal interactions or galaxy
formation processes. Cosmological hydrodynamical simulations have recently come
of age as a tool to study these alignments and their contamination to weak
gravitational lensing. We probe the redshift and luminosity evolution of
intrinsic alignments in Horizon-AGN between z=0 and z=3 for galaxies with an
r-band absolute magnitude of <-20. Alignments transition from being radial at
low redshifts and high luminosities, dominated by the contribution of
ellipticals, to being tangential at high redshift and low luminosities, where
discs dominate the signal. This cannot be explained by the evolution of the
fraction of ellipticals and discs alone: intrinsic evolution in the amplitude
of alignments is necessary. The alignment amplitude of elliptical galaxies
alone is smaller in amplitude by a factor of ~2, but has similar luminosity and
redshift evolution as in current observations and in the nonlinear tidal
alignment model at projected separations of > 1 Mpc. Alignments of discs are
null in projection and consistent with current low redshift observations. The
combination of the two populations yields an overall amplitude a factor of ~4
lower than observed alignments of luminous red galaxies with a steeper
luminosity dependence. The restriction on accurate galaxy shapes implies that
the galaxy population in the simulation is complete only to an r-band absolute
magnitude of <-20. Higher resolution simulations will be necessary to avoid
extrapolation of the intrinsic alignment predictions to the range of
luminosities probed by future surveys.


title:
Spatio-temporal analysis of micro economic activities in Rome reveals
  patterns of mixed-use urban evolution

abstract:
  Understanding urban growth is one with understanding how society evolves to
satisfy the needs of its individuals in sharing a common space and adapting to
the territory. We propose here a quantitative analysis of the historical
development of a large urban area by investigating the spatial distribution and
the age of commercial activities in the whole city of Rome. We find that the
age of activities of various categories presents a very interesting double
exponential trend, with a transition possibly related to the long-term
economical effects determined by the oil crisis of the Seventies. The
diversification of commercial categories, studied through various measures of
entropy, shows, among other interesting features, a saturating behaviour with
the density of activities. Moreover, different couples of commercial categories
exhibit over the years a tendency to attract in space. Our results demonstrate
that the spatio-temporal distribution of commercial activities can provide
important insights on the urbanisation processes at work, revealing specific
and not trivial socio-economical dynamics, as the presence of crisis periods
and expansion trends, and contributing to the characterisation of the maturity
of urban areas.


title:
Deterministic versus stochastic aspects of superexponential population
  growth models

abstract:
  Deterministic population growth models with power-law rates can exhibit a
large variety of growth behaviors, ranging from algebraic, exponential to
hyperexponential (finite time explosion). In this setup, selfsimilarity
considerations play a key role, together with two time substitutions. Two
stochastic versions of such models are investigated, showing a much richer
variety of behaviors. One is the Lamperti construction of selfsimilar positive
stochastic processes based on the exponentiation of spectrally positive
processes , followed by an appropriate time change. The other one is based on
stable continuous-state branching processes, given by another Lamperti time
substitution applied to stable spectrally positive processes.


title: On the number of Courant-sharp Dirichlet eigenvalues

abstract:
  We consider arbitrary open sets $\Omega$ in Euclidean space with finite
Lebesgue measure, and obtain upper bounds for (i) the largest Courant-sharp
Dirichlet eigenvalue of $\Omega$, (ii) the number of Courant-sharp Dirichlet
eigenvalues of $\Omega$. This extends recent results of P. B\'erard and B.
Helffer.


title:
Tuning the magnetocrystalline anisotropy in $R$CoPO by means of $R$
  substitution: a ferromagnetic resonance study

abstract:
  We report on broad-band electron spin resonance measurements performed within
the itinerant ferromagnetic phase of $R$CoPO ($R$ = La, Pr, Nd and Sm). We
reveal that the $R$ substitution is highly effective in gradually introducing a
sizeable easy-plane magnetocrystalline anisotropy within the Co sublattice. We
explain our results in terms of a subtle interplay of structural effects and of
indirect interactions between the $f$ and $d$ orbitals from $R$ and Co,
respectively.


title: A model for the quasistatic growth of cracks with fractional dimension

abstract:
  We study a variational model for the quasistatic growth of cracks with
fractional di- mension in brittle materials. We give a minimal set of
properties of the collection of admissible cracks which ensure the existence of
a quasistatic evolution. Both the an- tiplane and the planar cases are treated.


title: Snowflake geometry in CAT(0) groups

abstract:
  We construct CAT(0) groups containing subgroups whose Dehn functions are
given by $x^s$, for a dense set of numbers $s \in [2, \infty)$. This
significantly expands the known geometric behavior of subgroups of CAT(0)
groups.


title: The Ellis semigroup of a nonautonomous discrete dynamical system

abstract:
  We introduce the {\it Ellis semigroup} of a nonautonomous discrete dynamical
system $(X,f_{1,\infty})$ when $X$ is a metric compact space. The underlying
set of this semigroup is the pointwise closure of $\{f\sp{n}_1 \, |\, n\in
\mathbb{N}\}$ in the space $X\sp{X}$.
  By using the convergence of a sequence of points with respect to an
ultrafilter it is possible to give a precise description of the semigroup and
its operation. This notion extends the classical Ellis semigroup of a discrete
dynamical system. We show several properties that connect this semigroup and
the topological properties of the nonautonomous discrete dynamical system.


title:
Low-rank plus sparse decomposition for exoplanet detection in
  direct-imaging ADI sequences. The LLSG algorithm

abstract:
  Data processing constitutes a critical component of high-contrast exoplanet
imaging. Its role is almost as important as the choice of a coronagraph or a
wavefront control system, and it is intertwined with the chosen observing
strategy. Among the data processing techniques for angular differential imaging
(ADI), the most recent is the family of principal component analysis (PCA)
based algorithms. PCA serves, in this case, as a subspace projection technique
for constructing a reference point spread function (PSF) that can be subtracted
from the science data for boosting the detectability of potential companions
present in the data. Unfortunately, when building this reference PSF from the
science data itself, PCA comes with certain limitations such as the sensitivity
of the lower dimensional orthogonal subspace to non-Gaussian noise. Inspired by
recent advances in machine learning algorithms such as robust PCA, we aim to
propose a localized subspace projection technique that surpasses current
PCA-based post-processing algorithms in terms of the detectability of
companions at near real-time speed, a quality that will be useful for future
direct imaging surveys. We used randomized low-rank approximation methods
recently proposed in the machine learning literature, coupled with entry-wise
thresholding to decompose an ADI image sequence locally into low-rank, sparse,
and Gaussian noise components (LLSG). This local three-term decomposition
separates the starlight and the associated speckle noise from the planetary
signal, which mostly remains in the sparse term. We tested the performance of
our new algorithm on a long ADI sequence obtained on beta Pictoris with
VLT/NACO. Compared to a standard PCA approach, LLSG decomposition reaches a
higher signal-to-noise ratio and has an overall better performance in the
receiver operating characteristic space. (abridged).


title: Limit Theorems Associated With The Pitman-Yor Process

abstract:
  The Pitman-Yor process is a random discrete measure. The random weights or
masses follow the two-parameter Poisson-Dirichlet distribution with parameters
$0<\alpha<1, \theta>-\alpha$. The parameters $\alpha$ and $\theta$ correspond
to the stable and gamma components, respectively. The distribution of atoms is
given by a probability $\nu$. In this article we consider the limit theorems
for the Pitman-Yor process and the two-parameter Poisson-Dirichlet
distribution. These include law of large numbers, fluctuations, and moderate or
large deviation principles. The limiting procedures involve either $\alpha$
tends to zero or one. They arise naturally in genetics and physics such as the
asymptotic coalescence time for explosive branching process and the
approximation to generalized random energy model for disordered system.


title: Erratum for the time-like evolution in QCDNUM

abstract:
  A recent comparison of the evolution programs QCDNUM and APFEL showed a
discrepancy in the time-like evolution of the singlet fragmentation function at
NLO. It was found that the splitting functions of this evolution were wrongly
assigned in QCDNUM, and also that the fragmentation functions were not
correctly matched at the flavour thresholds. These errors are corrected in a
new release of the program.


title:
Floquet realization and signatures of one-dimensional anyons in an
  optical lattice

abstract:
  We propose a simple scheme for realizing the physics of 1D anyons with
ultracold bosonic atoms in an optical lattice. It relies on
lattice-shaking-induced resonant tunneling against potential off-sets created
by a combination of a lattice tilt and strong on-site interactions. No lasers
additional to those used for the creation of the optical lattice are required.
We also discuss experimental signatures of the continuous interpolation between
bosons and fermions when the statistical angle $\theta$ is varied from 0 to
$\pi$. Since the anyonic momentum distribution is not measurable in the bosonic
representation of the anyon model, we propose to use Friedel oscillations in
small systems as an alternative probe.


title: On the existence of non-free totally reflexive modules

abstract:
  For a standard graded Cohen-Macaulay ring $S$, if the quotient
$S/(\underline{x})$ admits non-free totally reflexive modules, where
$\underline{x}$ is a system of parameters consisting of elements of degree one,
then so does the ring $S$. As an application, we consider the question of which
Stanley-Reisner rings of graphs admit non-free totally reflexive modules.


title: Systems of Cosserat--Zhilin in Newtonian Mechanics

abstract:
  Mechanical systems of Cosserat--Zhilin are introduced as the main object of
Newtonian (non--relativistic) mechanics on the base of new notions of vector
calculus - sliders and screw measures (bi-measures). The differential equations
of motion are derived for different types of Cosserat--Zhilin systems in the
case where Stocks theorem is applicable. The paper defines multiplicative
groups which represent the measure of stress as a (well-defined) linear
isotropic map of {strain} tensor or tensor of {strain velocities} for classical
and polar continua in 2- and 3-dimensional cases.


title: Experimental generation of amplitude squeezed vector beams

abstract:
  We present an experimental method for the generation of amplitude squeezed
high-order vector beams. The light is modified twice by a spatial light
modulator such that the vector beam is created by means of a collinear
interferometric technique. A major advantage of this approach is that it avoids
systematic losses, which are detrimental as they cause decoherence in
continuous-variable quantum systems. The utilisation of a spatial light
modulator (SLM) gives the flexibility to switch between arbitrary mode orders.
The conversion efficiency with our setup is only limited by the efficiency of
the SLM. We show the experimental generation of Laguerre-Gauss (LG) modes with
radial indices up to 1 and azimuthal indices up to 3 with complex polarization
structures and a quantum noise reduction up to -0.9dB$\pm$0.1dB. The
corresponding polarization structures are studied in detail by measuring the
spatial distribution of the Stokes parameters.


title: Living Cognitive Society: a `digital' World of Views

abstract:
  The current social reality is characterized by all-encompassing change, which
disrupts existing social structures at all levels. Yet the prevailing view of
society is based on the ontological primacy of stable hierarchical structures,
which is no longer adequate.
  We propose a conceptual framework for thinking about a dynamically changing
social system: the Living Cognitive Society. Importantly, we show how it
follows from a much broader philosophical framework, guided by the theory of
individuation, which emphasizes the importance of relationships and interactive
processes in the evolution of a system.
  The framework addresses society as a living cognitive system -- an ecology of
interacting social subsystems -- each of which is also a living cognitive
system. We argue that this approach can help us to conceive sustainable social
systems that will thrive in the circumstances of accelerating change. The
Living Cognitive Society is explained in terms of its fluid structure, dynamics
and the mechanisms at work. We then discuss the disruptive effects of
Information and Communication Technologies on the mechanisms at work.
  We conclude by delineating a major topic for future research -- distributed
social governance -- which focuses on processes of coordination rather than on
stable structures within global society.


title:
Transiting Exoplanet Studies and Community Targets for JWST's Early
  Release Science Program

abstract:
  The James Webb Space Telescope will revolutionize transiting exoplanet
atmospheric science due to its capability for continuous, long-duration
observations and its larger collecting area, spectral coverage, and spectral
resolution compared to existing space-based facilities. However, it is unclear
precisely how well JWST will perform and which of its myriad instruments and
observing modes will be best suited for transiting exoplanet studies. In this
article, we describe a prefatory JWST Early Release Science (ERS) program that
focuses on testing specific observing modes to quickly give the community the
data and experience it needs to plan more efficient and successful future
transiting exoplanet characterization programs. We propose a multi-pronged
approach wherein one aspect of the program focuses on observing transits of a
single target with all of the recommended observing modes to identify and
understand potential systematics, compare transmission spectra at overlapping
and neighboring wavelength regions, confirm throughputs, and determine overall
performances. In our search for transiting exoplanets that are well suited to
achieving these goals, we identify 12 objects (dubbed "community targets") that
meet our defined criteria. Currently, the most favorable target is WASP-62b
because of its large predicted signal size, relatively bright host star, and
location in JWST's continuous viewing zone. Since most of the community targets
do not have well-characterized atmospheres, we recommend initiating preparatory
observing programs to determine the presence of obscuring clouds/hazes within
their atmospheres. Measurable spectroscopic features are needed to establish
the optimal resolution and wavelength regions for exoplanet characterization.
Other initiatives from our proposed ERS program include testing the instrument
brightness limits and performing phase-curve observations.(Abridged)


title: The evolution of self-gravitating accretion discs

abstract:
  It is quite likely that self-gravity will play an important role in the
evolution of accretion discs, in particular those around young stars, and those
around supermassive black holes. We summarise, here, our current understanding
of the evolution of such discs, focussing more on discs in young stellar
system, than on discs in active galactic nuclei. We consider the conditions
under which such discs may fragment to form bound objects, and when they might,
instead, be expected to settle into a quasi-steady, self-regulated state. We
also discuss how this understanding may depend on the mass of the disc relative
to the mass of the central object, and how it might depend on the presence of
external irradiation. Additionally, we consider whether or not fragmentation
might be stochastic, where we might expect it to occur in an actual
protostellar disc, and if there is any evidence for fragmentation actually
playing a role in the formation of planetary-mass bodies. Although there are
still a number of outstanding issue, such as the convergence of simulations of
self-gravitating discs, whether or not there is more than one mode of
fragmentation, and quite what role self-gravitating discs may play in the
planet formation process, our general understanding of these systems seems
quite robust.


title: Ultrafast a Distributed Arithmetic in multi-row codes

abstract:
  In this paper we consider the matrix structure of arithmetic processors based
on distributed arithmetic in multi-row codes. Scope - development of
supercomputers.


title: Invariants of pairs in SL(4,C) and SU(3,1)

abstract:
  We describe a minimal global coordinate system of order 30 on the
SL(4,C)-character variety of a rank 2 free group. Using symmetry within this
system, we obtain a smaller collection of 22 coordinates subject to 5 further
real relations that determine conjugation classes of generic pairs of matrices
in SU(3,1).


title: Exact Weighted Minwise Hashing in Constant Time

abstract:
  Weighted minwise hashing (WMH) is one of the fundamental subroutine, required
by many celebrated approximation algorithms, commonly adopted in industrial
practice for large scale-search and learning. The resource bottleneck of the
algorithms is the computation of multiple (typically a few hundreds to
thousands) independent hashes of the data. The fastest hashing algorithm is by
Ioffe \cite{Proc:Ioffe_ICDM10}, which requires one pass over the entire data
vector, $O(d)$ ($d$ is the number of non-zeros), for computing one hash.
However, the requirement of multiple hashes demands hundreds or thousands
passes over the data. This is very costly for modern massive dataset.
  In this work, we break this expensive barrier and show an expected constant
amortized time algorithm which computes $k$ independent and unbiased WMH in
time $O(k)$ instead of $O(dk)$ required by Ioffe's method. Moreover, our
proposal only needs a few bits (5 - 9 bits) of storage per hash value compared
to around $64$ bits required by the state-of-art-methodologies. Experimental
evaluations, on real datasets, show that for computing 500 WMH, our proposal
can be 60000x faster than the Ioffe's method without losing any accuracy. Our
method is also around 100x faster than approximate heuristics capitalizing on
the efficient "densified" one permutation hashing schemes
\cite{Proc:OneHashLSH_ICML14}. Given the simplicity of our approach and its
significant advantages, we hope that it will replace existing implementations
in practice.


title:
Coordinate Update Algorithms for Robust Power Loading for the MU-MISO
  Downlink with Outage Constraints

abstract:
  We consider the problem of power allocation for the single-cell multi-user
(MU) multiple-input single-output (MISO) downlink with quality-of-service (QoS)
constraints. The base station acquires an estimate of the channels and, for a
given beamforming structure, designs the power allocation so as to minimize the
total transmission power required to ensure that target
signal-to-interference-and-noise ratios at the receivers are met, subject to a
specified outage probability. We consider scenarios in which the errors in the
base station's channel estimates can be modelled as being zero-mean and
Gaussian. Such a model is particularly suitable for time division duplex (TDD)
systems with quasi-static channels, in which the base station estimates the
channel during the uplink phase. Under that model, we employ a precise
deterministic characterization of the outage probability to transform the
chance-constrained formulation to a deterministic one. Although that
deterministic formulation is not convex, we develop a coordinate descent
algorithm that can be shown to converge to a globally optimal solution when the
starting point is feasible. Insight into the structure of the deterministic
formulation yields approximations that result in coordinate update algorithms
with good performance and significantly lower computational cost. The proposed
algorithms provide better performance than existing robust power loading
algorithms that are based on tractable conservative approximations, and can
even provide better performance than robust precoding algorithms based on such
approximations.


title:
Reorientation of quantum Hall stripes within a partially filled Landau
  level

abstract:
  We investigate the effect of the filling factor on transport anisotropies,
known as stripes, in high Landau levels of a two-dimensional electron gas. We
find that at certain in-plane magnetic fields, the stripes orientation is
sensitive to the filling factor within a given Landau level. This sensitivity
gives rise to the emergence of stripes away from half-filling while an
orthogonally-oriented, native stripes reside at half-filling. This switching of
the anisotropy axes within a single Landau level can be attributed to a strong
dependence of the native symmetry breaking potential on the filling factor.


title:
A Linear Programming Approach to Dynamical Equivalence, Linear
  Conjugacy, and the Deficiency One Theorem

abstract:
  The well-known Deficiency One Theorem gives structural conditions on a
chemical reaction network under which, for any set of parameter values, the
steady states of the corresponding mass action system may be easily
characterized. It is also known, however, that mass action systems are not
uniquely associated with reaction networks and that some representations may
satisfy the Deficiency One Theorem while others may not. In this paper we
present a mixed-integer linear programming framework capable of determining
whether a given mass action system has a dynamically equivalent or linearly
conjugate representation which has an underlying network satisfying the
Deficiency One Theorem. This extends recent computational work determining
linearly conjugate systems which are weakly reversible and have a deficiency of
zero.


title: Cyclotron Resonance Gain for FIR and THz Radiation in Graphene

abstract:
  A cyclotron resonance maser source using low-effective-mass conduction
electrons in graphene, if successful, would allow for generation of Far
Infrared (FIR) and Terahertz (THz) radiation without requiring magnetic fields
running into the tens of Tesla. In order to investigate this possibility, we
consider a situation in which electrons are effectively injected via pumping
from the valence band to the conduction band using an infrared (IR) laser
source, subsequently gyrate in a magnetic field applied perpendicular to the
plane of the graphene, and give rise to gain for a FIR/THz wave crossing the
plane of the graphene. The treatment is classical, and includes on equal
footing the electron interation with the radiation field and the decay in
electron energy due to collisional processes. A set of integral expressions is
derived by assuming that the non-radiative energy loss processes of the
electrons can be adequately represented by a damping force proportional and
antiparallel to their momentum. Gain is found even though there is no inversion
of the energy distribution function. Gain can occur for electron damping times
as short as hundreds of femtoseconds.


title:
Degenerate higher order scalar-tensor theories beyond Horndeski and
  disformal transformations

abstract:
  We consider all degenerate scalar-tensor theories that depend quadratically
on second order derivatives of a scalar field, which we have identified in a
previous work. These theories, whose degeneracy in general ensures the absence
of Ostrogradski instability, include the quartic Horndenski Lagrangian as well
as its quartic extension beyond Horndeski, but also other families of
Lagrangians. We study how all these theories transform under general
conformal-disformal transformations and find that they can be separated into
three main classes that are stable under these transformations. This leads to a
complete classification modulo conformal-disformal transformations. Finally, we
show that these higher order theories include mimetic gravity and some
particular khronometric theories. They also contain theories that do not
correspond, to our knowledge, to already studied theories, even up to field
redefinitions.


title:
Social and Collaborative Services for Organizations: Back to
  Requirements

abstract:
  Social and collaborative services have widely spread within the enterprises
as they play a part in improving productivity and business outcomes. However,
the deployment of these services fluctuates between success and failure. This
paper intends to assess their deployment and how they can contribute to value
creation in different industries. We investigate the relationship between the
services' functionalities and the organizational requirement of these services
represented by the coordination. We also consider the organizational
transformation driven by servitization and emphasize its impact on the act of
coordination. We highlight the tight correlation between the functionalities
and the requirement in organic forms which suggests a successful deployment in
such enterprises. We nonetheless find that, when the servitization is a
strategic intent in organizations with mechanistic characteristics, deploying
social and collaborative services can contribute to achieving this aim.


title: Observation of pendular butterfly Rydberg molecules

abstract:
  Obtaining full control over the internal and external quantum states of
molecules is the central goal of ultracold chemistry and allows for the study
of coherent molecular dynamics, collisions and tests of fundamental laws of
physics. When the molecules additionally have a permanent electric dipole
moment, the study of dipolar quantum gases and spin-systems with long-range
interactions as well as applications in quantum information processing are
possible. Rydberg molecules constitute a class of exotic molecules, which are
bound by the interaction between the Rydberg electron and the ground state
atom. They exhibit extreme bond lengths of hundreds of Bohr radii and giant
permanent dipole moments in the kilo-Debye range. A special type with
exceptional properties are the so-called butterfly molecules, whose electron
density resembles the shape of a butterfly. Here, we report on the
photoassociation of butterfly Rydberg molecules and their orientation in a weak
electric field. Starting from a Bose-Einstein condensate of rubidium atoms, we
fully control the external degrees of freedom and spectroscopically resolve the
rotational structure and the emerging pendular states in an external electric
field. This not only allows us to extract the bond length, the dipole moment
and the angular momentum of the molecule but also to deterministically create
molecules with a tunable bond length and orientation. We anticipate direct
applications in quantum chemistry, many-body quantum physics and quantum
information processing.

categories: physics.atom-ph cond-mat.quant-gas physics.chem-ph quant-ph


title: The character and the wave front set correspondence in the stable range

abstract:
  We relate the distribution characters and the wave front sets of unitary
representation for real reductive dual pairs of type I in the stable range.


title:
A comprehensive analysis of the hard X-ray spectra of bright Seyfert
  galaxies

abstract:
  Hard X-ray spectra of 28 bright Seyfert galaxies observed with INTEGRAL were
analyzed together with the X-ray spectra from XMM-Newton, Suzaku and RXTE.
These broad-band data were fitted with a model assuming a thermal
Comptonization as a primary continuum component. We tested several model
options through a fitting of the Comptonized continuum accompanied by a complex
absorption and a Compton reflection. Both the large data set used and the model
space explored allowed us to accurately determine a mean temperature kTe of the
electron plasma, the Compton parameter y and the Compton reflection strength R
for the majority of objects in the sample. Our main finding is that a vast
majority of the sample (20 objects) is characterized by kTe < 100 keV, and only
for two objects we found kTe > 200 keV. The median kTe for entire sample is
48(-14,+57) keV. The distribution of the y parameter is bimodal, with a broad
component centered at ~0.8 and a narrow peak at ~1.1. A complex, dual absorber
model improved the fit for all data sets, compared to a simple absorption
model, reducing the fitted strength of Compton reflection by a factor of about
2. Modest reflection (median R ~0.32) together with a high ratio of Comptonized
to seed photon fluxes point towards a geometry with a compact hard X-ray
emitting region well separated from the accretion disc. Our results imply that
the template Seyferts spectra used in AGN population synthesis models should be
revised.


title: Microwave Photoresistance in an Ultrahigh Quality GaAs Quantum Well

abstract:
  The temperature dependence of microwave-induced resistance oscillations
(MIRO), according to the theory, originates from electron-electron scattering.
This scattering affects both the quantum lifetime, or the density of states,
and the inelastic lifetime, which governs the relaxation of the nonequilibrium
distribution function. Here, we report on MIRO in an ultrahigh mobility ($\mu >
3 \times 10^7$ cm$^2$/Vs) 2D electron gas at $T$ between $0.3$ K and $1.8$ K.
In contrast to theoretical predictions, the quantum lifetime is found to be
$T$-independent in the whole temperature range studied. At the same time, the
$T$-dependence of the inelastic lifetime is much \emph{stronger} than can be
expected from electron-electron interactions.


title:
The pion-kaon scattering amplitude constrained with forward dispersion
  relations up to 1.6 GeV

abstract:
  In this work we provide simple and precise parameterizations of the existing
$\pi K$ scattering data from threshold up to 1.6 GeV, which are constrained to
satisfy forward dispersion relations as well as three additional threshold sum
rules. We also provide phenomenological values of the threshold parameters and
of the resonance poles that appear in elastic scattering.


title:
We don't need no bounding-boxes: Training object class detectors using
  only human verification

abstract:
  Training object class detectors typically requires a large set of images in
which objects are annotated by bounding-boxes. However, manually drawing
bounding-boxes is very time consuming. We propose a new scheme for training
object detectors which only requires annotators to verify bounding-boxes
produced automatically by the learning algorithm. Our scheme iterates between
re-training the detector, re-localizing objects in the training images, and
human verification. We use the verification signal both to improve re-training
and to reduce the search space for re-localisation, which makes these steps
different to what is normally done in a weakly supervised setting. Extensive
experiments on PASCAL VOC 2007 show that (1) using human verification to update
detectors and reduce the search space leads to the rapid production of
high-quality bounding-box annotations; (2) our scheme delivers detectors
performing almost as good as those trained in a fully supervised setting,
without ever drawing any bounding-box; (3) as the verification task is very
quick, our scheme substantially reduces total annotation time by a factor
6x-9x.


title: Trace semantics for polymorphic references

abstract:
  We introduce a trace semantics for a call-by-value language with full
polymorphism and higher-order references. This is an operational game semantics
model based on a nominal interpretation of parametricity whereby polymorphic
values are abstracted with special kinds of names. The use of polymorphic
references leads to violations of parametricity which we counter by closely
recoding the disclosure of typing information in the semantics. We prove the
model sound for the full language and strengthen our result to full abstraction
for a large fragment where polymorphic references obey specific inhabitation
conditions.


title:
Resistively detected high-order magnetoplasmons in a high-quality 2D
  electron gas

abstract:
  We report on high-order magnetoplasmon resonances detected in photoresistance
in high-mobility GaAs quantum wells. These resonances manifest themselves as a
series of photoresistance extrema in the regime of Shubnikov-de Haas
oscillations. Extending to orders above 20, the extrema exhibit alternating
strength, being less (more) pronounced at even (odd) order magnetoplasmon
modes. This experimental technique provides sensitive and elegant means to
detect and investigate multiple magnetoplasmon modes and could be applied to
other systems.


title: Computable valued fields

abstract:
  We investigate the computability-theoretic properties of valued fields, and
in particular algebraically closed valued fields and $p$-adically closed valued
fields. We give an effectiveness condition, related to Hensel's lemma, on a
valued field which is necessary and sufficient to extend the valuation to any
algebraic extension. We show that there is a computable formally $p$-adic field
which does not embed into any computable $p$-adic closure, but we give an
effectiveness condition on the divisibility relation in the value group which
is sufficient to find such an embedding. By checking that algebraically closed
valued fields and $p$-adically closed valued fields of infinite transcendence
degree have the Mal'cev property, we show that they have computable dimension
$\omega$.


title:
The Research Space: using the career paths of scholars to predict the
  evolution of the research output of individuals, institutions, and nations

abstract:
  In recent years scholars have built maps of science by connecting the
academic fields that cite each other, are cited together, or that cite a
similar literature. But since scholars cannot always publish in the fields they
cite, or that cite them, these science maps are only rough proxies for the
potential of a scholar, organization, or country, to enter a new academic
field. Here we use a large dataset of scholarly publications disambiguated at
the individual level to create a map of science-or research space-where links
connect pairs of fields based on the probability that an individual has
published in both of them. We find that the research space is a significantly
more accurate predictor of the fields that individuals and organizations will
enter in the future than citation based science maps. At the country level,
however, the research space and citations based science maps are equally
accurate. These findings show that data on career trajectories-the set of
fields that individuals have previously published in-provide more accurate
predictors of future research output for more focalized units-such as
individuals or organizations-than citation based science maps.


title: Towards Least Privilege Containers with Cimplifier

abstract:
  Application containers, such as Docker containers, have recently gained
popularity as a solution for agile and seamless deployment of applications.
These light-weight virtualization environments run applications that are packed
together with their resources and configuration information, and thus can be
deployed across various software platforms. However, these software ecosystems
are not conducive to the true and tried security principles of privilege
separation (PS) and principle of least privilege (PLP). We propose algorithms
and a tool Cimplifier, which address these concerns in the context of
containers. Specifically, given a container our tool partitions them into
simpler containers, which are only provided enough resources to perform their
functionality. As part our solution, we develop techniques for analyzing
resource usage, for performing partitioning, and gluing the containers together
to preserve functionality. Our evaluation on real-world containers demonstrates
that Cimplifier can preserve the original functionality, leads to reduction in
image size of 58-95%, and processes even large containers in under thirty
seconds.


title:
Geometry of system-bath coupling and gauge fields in bosonic ladders:
  manipulating currents and driving phase transitions

abstract:
  Quantum systems in contact with an environment display a rich physics
emerging from the interplay between dissipative and Hamiltonian terms. Here we
focus on the role of the geometry of the coupling between the system and the
baths. In the specific we consider a dissipative boundary driven ladder in
presence of a gauge field which can be implemented with ion microtraps arrays.
We show that, depending on the geometry, the currents imposed by the baths can
be strongly affected by the gauge field resulting in non-equilibrium phase
transitions. In different phases both the magnitude of the current and its
spatial distribution are significantly different. These findings allow for
novel strategies to manipulate and control transport properties in quantum
systems.


title: Fast inference of ill-posed problems within a convex space

abstract:
  In multiple scientific and technological applications we face the problem of
having low dimensional data to be justified by a linear model defined in a high
dimensional parameter space. The difference in dimensionality makes the problem
ill-defined: the model is consistent with the data for many values of its
parameters. The objective is to find the probability distribution of parameter
values consistent with the data, a problem that can be cast as the exploration
of a high dimensional convex polytope. In this work we introduce a novel
algorithm to solve this problem efficiently. It provides results that are
statistically indistinguishable from currently used numerical techniques while
its running time scales linearly with the system size. We show that the
algorithm performs robustly in many abstract and practical applications. As
working examples we simulate the effects of restricting reaction fluxes on the
space of feasible phenotypes of a {\em genome} scale E. Coli metabolic network
and infer the traffic flow between origin and destination nodes in a real
communication network.

categories: cs.OH cond-mat.dis-nn cond-mat.stat-mech q-bio.MN


title: Exact solution for a sample space reducing stochastic process

abstract:
  Stochastic processes wherein the size of the state space is changing as a
function of time offer models for the emergence of scale-invariant features
observed in complex systems. I consider such a sample-space reducing (SSR)
stochastic process that results in a random sequence of strictly decreasing
integers $\{x(t)\}$, $0\le t \le \tau$, with boundary conditions $x(0) = N$ and
$x(\tau)$ = 1. This model is shown to be exactly solvable:
$\mathcal{P}_N(\tau)$, the probability that the process survives for time
$\tau$ is analytically evaluated. In the limit of large $N$, the asymptotic
form of this probability distribution is Gaussian, with mean and variance both
varying logarithmically with system size: $\langle \tau \rangle \sim \ln N$ and
$\sigma_{\tau}^{2} \sim \ln N$. Correspondence can be made between survival
time statistics in the SSR process and record statistics of i.i.d. random
variables.


title:
Reconfigurable photonic integrated mode (de)multiplexer for SDM fiber
  transmission

abstract:
  A photonic integrated circuit for mode multiplexing and demultiplexing in a
few-mode fiber is presented and demonstrated. Two 10 Gbit/s channels at the
same wavelength and polarization are simultaneously transmitted over modes LP01
and LP11a of a few-mode fiber exploiting the integrated mode MUX and DEMUX. The
proposed Indium-Phosphide-based circuits have a good coupling efficiency with
fiber modes with mode-dependant loss smaller than 1 dB. Measured mode
excitation cross-talk is as low as -20 dB and a channel cross-talk after
propagation and demultiplexing of -15 dB is achieved. An operational bandwidth
of the full transmission system of at least 10 nm is demonstrated. Both mode
MUX and DEMUX are fully reconfigurable and allow a dynamic switch of channel
routing in the transmission system.


title:
Water dispersible CoFe2O4 nanoparticles with improved colloidal
  stability for biomedical applications

abstract:
  Single phase cobalt ferrite (CoFe2O4, CFO) nanoparticles of a controlled size
(~ 6 nm) exhibiting superparamagnetic properties have been synthesized by
hydrothermal technique using oleic acid (OA) as surfactant. The oleic acid
coated CFO nanoparticles are stable in non-polar organic media, such as hexane
but are not well dispersible in water. The surface of these snanoparticles has
been further modified by citric acid using ligand exchange process, which makes
CFO nanoparticles more stable colloidal solution in water. Citric acid coated
CFO nanoparticles exhibits high dispersibility in water, high zeta potential,
very low coercivity and moderate saturation magnetization. Biocompatibility of
these CFO nanoparticles is demonstrated through cytotoxicity test in L929 cell
line.


title:
Graviton Creation by Small Scale Factor Oscillations in an Expanding
  Universe

abstract:
  We treat quantum creation of gravitons by small scale factor oscillations
around the average of an expanding universe. Such oscillations can arise in
standard general relativity due to oscillations of a homogeneous, minimally
coupled scalar field. They can also arise in modified gravity theories with a
term proportional to the square of the Ricci scalar in the gravitational
action. The graviton wave equation is different in the two cases, leading to
somewhat different creation rates. Both cases are treated using a perturbative
method due to Birrell and Davies, involving an expansion in a conformal
coupling parameter to calculate the number density and energy density of the
created gravitons. Cosmological constraints on the present graviton energy
density and the dimensionless amplitude of the oscillations are discussed. We
also discuss decoherence of quantum systems produced by the spacetime geometry
fluctuations due to such a graviton bath.


title:
Mathematical transcription of the "Time-Based Resource Sharing" theory
  of working memory

abstract:
  The time-based resource sharing (TBRS) model is a prominent model of working
memory that is both predictive and simple. The TBRS is the mainstream
decay-based model and the most susceptible to competition with
interference-based models. A connectionist implementation of the TBRS, the
TBRS*, has recently been developed. However, the TBRS* is an enriched version
of the TBRS, making it difficult to test the general characteristics resulting
from the TBRS assumptions. Here, we describe a novel model, the TBRS2, built to
be more transparent and simple than the TBRS*. The TBRS2 is minimalist and
allows only a few parameters. It is a straightforward mathematical
transcription of the TBRS that focuses exclusively on the activation level of
memory items as a function of time. Its simplicity makes it possible to derive
several theorems from the original TBRS and allows several variants of the
refreshing process to be tested without relying on particular architectures.


title: Multivariate Hawkes Processes for Large-scale Inference

abstract:
  In this paper, we present a framework for fitting multivariate Hawkes
processes for large-scale problems both in the number of events in the observed
history $n$ and the number of event types $d$ (i.e. dimensions). The proposed
Low-Rank Hawkes Process (LRHP) framework introduces a low-rank approximation of
the kernel matrix that allows to perform the nonparametric learning of the
$d^2$ triggering kernels using at most $O(ndr^2)$ operations, where $r$ is the
rank of the approximation ($r \ll d,n$). This comes as a major improvement to
the existing state-of-the-art inference algorithms that are in $O(nd^2)$.
Furthermore, the low-rank approximation allows LRHP to learn representative
patterns of interaction between event types, which may be valuable for the
analysis of such complex processes in real world datasets. The efficiency and
scalability of our approach is illustrated with numerical experiments on
simulated as well as real datasets.


title: Modified Magnetohydrodynamics Around the Electroweak Transition

abstract:
  We analyse solutions of the MHD equations around the electroweak transition
taking into account the effects of the chiral anomaly. It is shown that a
transition that is not of the first order has direct consequences on the
evolution of the asymmetry between left- and right-handed leptons. Assuming an
initial chiral asymmetry in the symmetric phase at temperatures higher than the
transition temperature, as well as the existence of magnetic fields, it is
demonstrated that the asymmetry typically grows with time, until it undergoes a
fast decrease at the transition, and then eventually gets damped at lower
temperatures in the broken phase. We argue that it is unlikely to have any
significant magnetic field amplification as a consequence of the electroweak
transition in the Standard model, even when the chiral anomaly is introduced.
The presence of a chiral asymmetry between left- and right-handed charge
carriers naturally leads to the creation of helical magnetic fields from
non-helical fields and this can have consequences on their subsequent
evolution.


title: The Magnetic Structure of Paramagnetic MnO

abstract:
  Using a combination of single-crystal neutron scattering and reverse Monte
Carlo refinements, we study the magnetic structure of paramagnetic MnO at a
temperature (160\,K) substantially below the Curie-Weiss temperature
$|\theta|\sim550$\,K. The microscopic picture we develop reveals a
locally-ordered domain structure that persists over distances many times larger
than the correlation length implied by direct analysis of the spin correlation
function. Moreover, the directional dependence of paramagnetic spin
correlations in paramagnetic MnO differs in some important respects from that
of its incipient ordered antiferromagnetic state. Our results have implications
for the understanding of paramagnetic states in weakly-frustrated systems,
including high-temperature superconductors.


title:
$\chi^{\vphantom\dagger}_{c0}(3915)$ As the Lightest $c\bar c s \bar s$
  State

abstract:
  The state $\chi^{\vphantom\dagger}_{c0}(3915)$ has recently been demoted by
the Particle Data Group from its previous status as the conventional $c\bar c$
$2 {}^3P_0$ state, largely due to the absence of expected $D\bar D$ decays. We
propose that $\chi^{\vphantom\dagger}_{c0}(3915)$ is actually the lightest
$c\bar c s \bar s$ state, and calculate the spectrum of such states using the
diquark model, identifying many of the observed charmoniumlike states that lack
open-charm decay modes as $c\bar c s \bar s$. Among other results, we argue
that $Y(4140)$ is a $J^{PC} = 1^{++}$ $c\bar c s \bar s$ state that has been
not been seen in two-photon fusion largely as a consequence of the Landau-Yang
theorem.


title:
Single atom detection in ultracold quantum gases: a review of current
  progress

abstract:
  The recent advances in single atom detection and manipulation in experiments
with ultracold quantum gases are reviewed. The discussion starts with the basic
principles of trapping, cooling and detecting single ions and atoms. The
realization of single atom detection in ultracold quantum gases is presented in
detail and the employed methods, which are based on light scattering, electron
scattering, field ionization and direct neutral particle detection are
discussed. The microscopic coherent manipulation of single atoms in a quantum
gas is also covered. Various examples are given in order to highlight the power
of these approaches to study many-body quantum systems.


title: Enabling Digital Health by Automatic Classification of Short Messages

abstract:
  In response to the growing HIV/AIDS and other health-related issues, UNICEF
through their U-Report platform receives thousands of messages (SMS) every day
to provide prevention strategies, health case advice, and counsel- ing support
to vulnerable population. Due to a rapid increase in U-Report usage (up to 300%
in last 3 years), plus approximately 1,000 new registrations each day, the
volume of messages has thus continued to increase, which made it impossible for
the team at UNICEF to process them in a timely manner. In this paper, we
present a platform designed to perform automatic classification of short
messages (SMS) in real-time to help UNICEF categorize and prioritize
health-related messages as they arrive. We employ a hybrid approach, which
combines human and machine intelligence that seeks to resolve the information
overload issue by introducing processing of large-scale data at high-speed
while maintaining a high classification accuracy. The system has recently been
tested in conjunction with UNICEF in Zambia to classify short messages received
via the U-Report platform on various health related issues. The system is
designed to enable UNICEF make sense of a large volume of short messages in a
timely manner. In terms of evaluation, we report design choices, challenges,
and performance of the system observed during the deployment to validate its
effectiveness.


title:
Quantum simulators based on the global collective light-matter
  interaction

abstract:
  We show that coupling ultracold atoms in optical lattices to quantized modes
of an optical cavity leads to quantum phases of matter, which at the same time
posses properties of systems with both short- and long-range interactions. This
opens perspectives for novel quantum simulators of finite-range interacting
systems, even though the light-induced interaction is global (i.e. infinitely
long range). This is achieved by spatial structuring of the global light-matter
coupling at a microscopic scale. Such simulators can directly benefit from the
collective enhancement of the global light-matter interaction and constitute an
alternative to standard approaches using Rydberg atoms or polar molecules. The
system in the steady state of light induces effective many-body interactions
that change the landscape of the phase diagram of the typical Bose-Hubbard
model. Therefore, the system can support non-trivial superfluid states, bosonic
dimer, trimers, etc. states and supersolid phases depending on the choice of
the wavelength and pattern of the light with respect to the classical optical
lattice potential. We find that by carefully choosing the system parameters one
can investigate diverse strongly correlated physics with the same setup, i.e.,
modifying the geometry of light beams. In particular, we present the interplay
between the density and bond (or matter-wave coherence) interactions. We show
how to tune the effective interaction length in such a hybrid system with both
short-range and global interactions.

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


title: Shape-aware Surface Reconstruction from Sparse 3D Point-Clouds

abstract:
  The reconstruction of an object's shape or surface from a set of 3D points
plays an important role in medical image analysis, e.g. in anatomy
reconstruction from tomographic measurements or in the process of aligning
intra-operative navigation and preoperative planning data. In such scenarios,
one usually has to deal with sparse data, which significantly aggravates the
problem of reconstruction. However, medical applications often provide
contextual information about the 3D point data that allow to incorporate prior
knowledge about the shape that is to be reconstructed. To this end, we propose
the use of a statistical shape model (SSM) as a prior for surface
reconstruction. The SSM is represented by a point distribution model (PDM),
which is associated with a surface mesh. Using the shape distribution that is
modelled by the PDM, we formulate the problem of surface reconstruction from a
probabilistic perspective based on a Gaussian Mixture Model (GMM). In order to
do so, the given points are interpreted as samples of the GMM. By using mixture
components with anisotropic covariances that are "oriented" according to the
surface normals at the PDM points, a surface-based fitting is accomplished.
Estimating the parameters of the GMM in a maximum a posteriori manner yields
the reconstruction of the surface from the given data points. We compare our
method to the extensively used Iterative Closest Points method on several
different anatomical datasets/SSMs (brain, femur, tibia, hip, liver) and
demonstrate superior accuracy and robustness on sparse data.


title: A Union of Euclidean Metric Spaces is Euclidean

abstract:
  Suppose that a metric space $X$ is the union of two metric subspaces $A$ and
$B$ that embed into Euclidean space with distortions $D_A$ and $D_B$,
respectively. We prove that then $X$ embeds into Euclidean space with a bounded
distortion (namely, with distortion at most $7D_A D_B + 2(D_A+D_B)$). Our
result settles an open problem posed by Naor. Additionally, we present some
corollaries and extensions of this result. In particular, we introduce and
study a new concept of an "external bi-Lipschitz extension".
  In the end of the paper, we list a few related open problems.


title: Some conditionally hard problems on links and 3-manifolds

abstract:
  We show that three natural decision problems about links and 3-manifolds are
computationally hard, assuming some conjectures in complexity theory. The first
problem is determining whether a link in the 3-sphere bounds a Seifert surface
with Thurston norm at most a given integer; this is shown to be NP-complete.
The second problem is the homeomorphism problem for closed 3-manifolds; this is
shown to be at least as hard as the graph isomorphism problem. The third
problem is determining whether a given link in the 3-sphere is a sublink of
another given link; this is shown to be NP-hard.


title:
Quenched invariance principles for the random conductance model on a
  random graph with degenerate ergodic weights

abstract:
  We consider a stationary and ergodic random field $\{\omega(e) : e \in E_d\}$
that is parameterized by the edge set of the Euclidean lattice $\mathbb{Z}^d$,
$d \geq 2$. The random variable $\omega(e)$, taking values in $[0, \infty)$ and
satisfying certain moment bounds, is thought of as the conductance of the edge
$e$. Assuming that the set of edges with positive conductances give rise to a
unique infinite cluster $\mathcal{C}_{\infty}(\omega)$, we prove a quenched
invariance principle for the continuous-time random walk among random
conductances under relatively mild conditions on the structure of the infinite
cluster. An essential ingredient of our proof is a new anchored relative
isoperimetric inequality.


title: No such thing as a risk-neutral market

abstract:
  A very brief history of relative valuation in neoclassical finance since 1973
is presented, with attention to core currency issues for emerging economies.
Price formation is considered in the context of hierarchical causality, with
discussion focussed on identifying mathematical modelling challenges for robust
and transparent regulation of interactions.


title: Neutrino footprint in Large Scale Structure

abstract:
  Recent constrains on the sum of neutrino masses inferred by analyzing
cosmological data, show that detecting a non-zero neutrino mass is within reach
of forthcoming cosmological surveys, implying a direct determination of the
absolute neutrino mass scale. The measurement relies on constraining the shape
of the matter power spectrum below the neutrino free streaming scale: massive
neutrinos erase power at these scales. Detection of a lack of small-scale
power, however, could also be due to a host of other effects. It is therefore
of paramount importance to validate neutrinos as the source of power
suppression at small scales. We show that, independent on hierarchy, neutrinos
always show a footprint on large, linear scales; the exact location and
properties can be related to the measured power suppression (an astrophysical
measurement) and atmospheric neutrinos mass splitting (a neutrino oscillation
experiment measurement). This feature can not be easily mimicked by systematic
uncertainties or modifications in the cosmological model. The measurement of
such a feature, up to 1% relative change in the power spectrum, is a smoking
gun for confirming the determination of the absolute neutrino mass scale from
cosmological observations. It also demonstrates the synergy of astrophysics and
particle physics experiments.


title: Applications of lattice QCD techniques for condensed matter systems

abstract:
  We review the application of lattice QCD techniques, most notably the Hybrid
Monte-Carlo (HMC) simulations, to first-principle study of tight-binding models
of crystalline solids with strong inter-electron interactions. After providing
a basic introduction into the HMC algorithm as applied to condensed matter
systems, we review HMC simulations of graphene, which in the recent years have
helped to understand the semi-metal behavior of clean suspended graphene at the
quantitative level. We also briefly summarize other novel physical results
obtained in these simulations. Then we comment on the applicability of Hybrid
Monte-Carlo to topological insulators and Dirac and Weyl semi-metals and
highlight some of the relevant open physical problems. Finally, we also touch
upon the lattice strong-coupling expansion technique as applied to condensed
matter systems.


title:
Spectral properties and chiral symmetry violations of (staggered) domain
  wall fermions in the Schwinger model

abstract:
  We follow up on a suggestion by Adams and construct explicit domain wall
fermion operators with staggered kernels. We compare different domain wall
formulations, namely the standard construction as well as Borici's modified and
Chiu's optimal construction, utilizing both Wilson and staggered kernels. In
the process, we generalize the staggered kernels to arbitrary even dimensions
and introduce both truncated and optimal staggered domain wall fermions. Some
numerical investigations are carried out in the (1+1)-dimensional setting of
the Schwinger model, where we explore spectral properties of the bulk,
effective and overlap Dirac operators in the free-field case, on quenched
thermalized gauge configurations and on smooth topological configurations. We
compare different formulations using the effective mass, deviations from
normality and violations of the Ginsparg-Wilson relation as measures of
chirality.


title: Reionization during the dark ages from a cosmic axion background

abstract:
  Recently it has been pointed out that a cosmic background of relativistic
axion-like particles (ALPs) would be produced by the primordial decays of heavy
fields in the post-inflation epoch, contributing to the extra-radiation content
in the Universe today. Primordial magnetic fields would trigger conversions of
these ALPs into sub-MeV photons during the dark ages. This photon flux would
produce an early reionization of the Universe, leaving a significant imprint on
the total optical depth to recombination $\tau$. Using the current measurement
of $\tau$ and the limit on the extra-radiation content $\Delta N_{\rm eff} $ by
the Planck experiment we put a strong bound on the ALP-photon conversions.
Namely we obtain upper limits on the product of the photon-ALP coupling
constant $g_{a\gamma}$ times the magnetic field strength $B$ down to
$g_{a\gamma} B \gtrsim 6 \times 10^{-18} \textrm{GeV}^{-1} \textrm{nG} $ for
ultralight ALPs.


title:
No precise localization for FRB 150418: claimed radio transient is AGN
  variability

abstract:
  Keane et al. have recently claimed to have obtained the first precise
localization for a Fast Radio Burst (FRB) thanks to the identification of a
contemporaneous fading slow (~week-timescale) radio transient. They use this
localization to pinpoint the FRB to a galaxy at z ~ 0.49 that exhibits no
discernable star formation activity. We argue that the transient is not genuine
and that the host candidate, WISE J071634.59-190039.2, is instead a radio
variable: the available data did not exclude this possibility; a random radio
variable consistent with the observations is not unlikely to have a redshift
compatible with the FRB dispersion measure; and the proposed transient light
curve is better explained as a scintillating steady source, perhaps also
showing an active galactic nucleus (AGN) flare, than a synchrotron-emitting
blastwave. The radio luminosity of the host candidate implies that it is an AGN
and we present new late-time Very Large Array observations showing that the
galaxy is indeed variable at a level consistent with the claimed transient.
Therefore the claimed precise localization and redshift determination for FRB
150418 cannot be justified.


title:
Thompson's theorem for compact operators and diagonals of unitary
  operators

abstract:
  As applications of Kadison's Pythageorean and carpenter's theorems, the
Schur-Horn theorem, and Thompson's theorem, we obtain an extension of Thompsons
theorem to compact operators and use these ideas to give a characterization of
diagonals of unitary operators. Thompson's mysterious inequality concerning the
last terms of the diagonal and singular value sequences plays a central role.


title:
High Energy Neutrinos from the Gravitational Wave event GW150914
  possibly associated with a short Gamma-Ray Burst

abstract:
  High-energy neutrino (HEN) and gravitational wave (GW) can probe
astrophysical sources in addition to electromagnetic observations.
Multimessenger studies can reveal nature of the sources which may not be
discerned from one type of signal alone. We discuss HEN emission in connection
with the Advanced Laser Interferometer Gravitational-wave Observatory (ALIGO)
event GW150914 which could be associated with a short gamma-ray burst (GRB)
detected by the $Fermi$ Gamma-ray Burst Monitor (GBM) 0.4 s after the GW event
and within localization uncertainty of the GW event. We calculate HEN flux from
this short GRB, GW150914-GBM, and show that non-detection of a high-energy
starting event (HESE) by the IceCube Neutrino Observatory can constrain the
total isotropic-equivalent jet energy of this short burst to be less than
$3\times 10^{52}$ erg.


title: Energy Cost of Creating Quantum Coherence

abstract:
  We consider the physical situations where the resource theories of coherence
and thermodynamics play competing roles. In particular, we study the creation
of quantum coherence using unitary operations with limited thermodynamic
resources. We first find the maximal coherence that can be created under
unitary operations starting from a thermal state and find explicitly the
unitary transformation that creates the maximal coherence. Since coherence is
created by unitary operations starting from a thermal state, it requires some
amount of energy. This motivates us to explore the trade-off between the amount
of coherence that can be created and the energy cost of the unitary process. We
find the maximal achievable coherence under the constraint on the available
energy. Additionally, we compare the maximal coherence and the maximal total
correlation that can be created under unitary transformations with the same
available energy at our disposal. We find that when maximal coherence is
created with limited energy, the total correlation created in the process is
upper bounded by the maximal coherence and vice versa. For two qubit systems we
show that there does not exist any unitary transformation that creates maximal
coherence and maximal total correlation simultaneously with a limited energy
cost.


title:
Stability analysis of thermo-acoustic nonlinear eigenproblems in annular
  combustors. Part I. Sensitivity

abstract:
  We present an adjoint-based method for the calculation of eigenvalue
perturbations in nonlinear, degenerate and non self-adjoint eigenproblems. This
method is applied to a thermo-acoustic annular combustor network, the stability
of which is governed by a nonlinear eigenproblem. We calculate the first- and
second-order sensitivities of the growth rate and frequency to geometric, flow
and flame parameters. Three different configurations are analysed. The
benchmark sensitivities are obtained by finite difference, which involves
solving the nonlinear eigenproblem at least as many times as the number of
parameters. By solving only one adjoint eigenproblem, we obtain the
sensitivities to any thermo-acoustic parameter, which match the
finite-difference solutions at much lower computational cost.


title: Dark matter relic density from observations of supersymmetry at the ILC

abstract:
  Supersymmetry can explain the observed dark matter relic density with a
neutralino dark matter particle and a coannihilating, almost mass-degenerate
sparticle. If this were the case in nature, a linear electron positron collider
like the ILC could discover the two sparticles if their masses are in the
kinematic reach of the collider. This contribution discusses which observations
are necessary at the ILC for predicting the dark matter relic density correctly
and for confirming that the observed lightest neutralino is the only kind of
dark matter. We take the case of stau coannihilation as an example.


title:
Stability analysis of thermo-acoustic nonlinear eigenproblems in annular
  combustors. Part II. Uncertainty quantification

abstract:
  Monte Carlo and Active Subspace Identification methods are combined with
first- and second-order adjoint sensitivities to perform (forward) uncertainty
quantification analysis of the thermo-acoustic stability of two annular
combustor configurations. This method is applied to evaluate the risk factor,
i.e., the probability for the system to be unstable. It is shown that the
adjoint approach reduces the number of nonlinear-eigenproblem calculations by
up to $\sim\mathcal{O}(M)$, as many as the Monte Carlo samples.


title: Prompt neutrino flux in the atmosphere revisited

abstract:
  Prompt neutrino fluxes due to the interactions of high-energy cosmic rays
with the Earth's atmosphere are backgrounds in the search for high-energy
neutrinos of galactic or extra-galactic origin performed by Very Large Volume
Neutrino Telescopes. We summarize our predictions for prompt neutrinos, showing
their basic features as emerging from the calculation in a QCD framework
capable of describing recent charm data from the Large Hadron Collider.


title:
Escaping the trap of 'blocking': a kinetic model linking economic
  development and political competition

abstract:
  In this paper we present a kinetic model with stochastic game-type
interactions, analyzing the relationship between the level of political
competition in a society and the degree of economic liberalization. The above
issue regards the complex interactions between economy and institutional
policies intended to introduce technological innovations in a society, where
technological innovations are intended in a broad sense comprehending reforms
critical to production. A special focus is placed on the political replacement
effect described in a macroscopic model by Acemoglu and Robinson (AR-model,
henceforth), which can determine the phenomenon of innovation 'blocking',
possibly leading to economic backwardness. One of the goals of our modelization
is to obtain a mesoscopic dynamical model whose macroscopic outputs are
qualitatively comparable with stylized facts of the AR-model. A set of
numerical solutions is presented showing the non monotonous relationship
between economic liberization and political competition, which can be
considered as an emergent phenomenon of the complex socio-economic interaction
dynamic.


title: The Casimir-Polder effect for a stack of conductive planes

abstract:
  The Casimir-Polder interaction between an atom and a multilayered system
composed of infinitely thin planes is considered using the zeta-function
regularization approach with summation of the zero-point energies. As a
prototype material, each plane is represented by a graphene sheet whose optical
response is described by a constant conductivity or Drude-Lorentz model
conductivity. Asymptotic expressions for various separations are derived and
compared to numerical calculations. We distinguish between large atom/plane
limit, where retardation effects are prominent, and small atom/plane limit,
where the typical van der Waals coefficient is found to be dependent on the
number of graphenes and characteristic distances. The calculated energies for
different atoms and graphene conductivity models brings forward the basic
science of the Casimir-Polder effect and suggests ways to manipulate this
interaction experimentally.


title:
Optimizing Power and User Association for Energy Saving in Load-Coupled
  Cooperative LTE

abstract:
  We consider an energy minimization problem for cooperative LTE networks. To
reduce energy consumption, we investigate how to jointly optimize the transmit
power and the association between cells and user equipments (UEs), by taking
into consideration joint transmission (JT), one of the coordinated multipoint
(CoMP) techniques. We formulate the optimization problem mathematically. For
solving the problem, a dynamic power allocation algorithm that adjusts the
transmit power of all cells, and an algorithm for optimizing the cell-UE
association, are proposed. The two algorithms are iteratively used in an
algorithmic framework to enhance the energy performance. Numerically, the
proposed algorithms can lead to lower energy consumption than the optimal
energy setting in the non-JT case. In comparison to fixed power allocation in
JT, the proposed dynamic power allocation algorithm is able to significantly
reduce the energy consumption.


title: Compacton formation under Allen--Cahn dynamics

abstract:
  We study the solutions of a generalized Allen-Cahn equation deduced from a
Landau energy functional, endowed with a non-constant higher order stiffness.
We analytically solve the stationary problem and deduce the existence of
so-called compactons, namely, connections on a finite interval between the two
phases. The dynamics problem is numerically solved and compacton formation is
described.


title:
Load Balancing via Joint Transmission in Heterogeneous LTE: Modeling and
  Computation

abstract:
  As one of the Coordinated Multipoint (CoMP) techniques, Joint Transmission
(JT) can improve the overall system performance. In this paper, from the load
balancing perspective, we study how the maximum load can be reduced by
optimizing JT pattern that characterizes the association between cells and User
Equipments (UEs). To give a model of the interference caused by cells with
different time-frequency resource usage, we extend a load coupling model, by
taking into account JT. In this model, the mutual interference depends on the
load of cells coupled in a non-linear system with each other. Under this model,
we study a two-cell case and proved that the optimality is achieved in linear
time in the number of UEs. After showing the complexity of load balancing in
the general network scenario, an iterative algorithm for minimizing the maximum
load, named JT-MinMax, is proposed. We evaluate JT-MinMax in a Heterogeneous
Network (HetNet), though it is not limited to this type of scenarios. Numerical
results demonstrate the significant performance improvement of JT-MinMax on
min-max cell load, compared to the conventional non-JT solution where each UE
is served by the cell with best received transmit signal.


title:
A Neutrosophic Recommender System for Medical Diagnosis Based on
  Algebraic Neutrosophic Measures

abstract:
  Neutrosophic set has the ability to handle uncertain, incomplete,
inconsistent, indeterminate information in a more accurate way. In this paper,
we proposed a neutrosophic recommender system to predict the diseases based on
neutrosophic set which includes single-criterion neutrosophic recommender
system (SC-NRS) and multi-criterion neutrosophic recommender system (MC-NRS).
Further, we investigated some algebraic operations of neutrosophic recommender
system such as union, complement, intersection, probabilistic sum, bold sum,
bold intersection, bounded difference, symmetric difference, convex linear sum
of min and max operators, Cartesian product, associativity, commutativity and
distributive. Based on these operations, we studied the algebraic structures
such as lattices, Kleen algebra, de Morgan algebra, Brouwerian algebra, BCK
algebra, Stone algebra and MV algebra. In addition, we introduced several types
of similarity measures based on these algebraic operations and studied some of
their theoretic properties. Moreover, we accomplished a prediction formula
using the proposed algebraic similarity measure. We also proposed a new
algorithm for medical diagnosis based on neutrosophic recommender system.
Finally to check the validity of the proposed methodology, we made experiments
on the datasets Heart, RHC, Breast cancer, Diabetes and DMD. At the end, we
presented the MSE and computational time by comparing the proposed algorithm
with the relevant ones such as ICSM, DSM, CARE, CFMD, as well as other variants
namely Variant 67, Variant 69, and Varian 71 both in tabular and graphical form
to analyze the efficiency and accuracy. Finally we analyzed the strength of all
8 algorithms by ANOVA statistical tool.


title: Simple Bayesian Algorithms for Best Arm Identification

abstract:
  This paper considers the optimal adaptive allocation of measurement effort
for identifying the best among a finite set of options or designs. An
experimenter sequentially chooses designs to measure and observes noisy signals
of their quality with the goal of confidently identifying the best design after
a small number of measurements. This paper proposes three simple and intuitive
Bayesian algorithms for adaptively allocating measurement effort, and
formalizes a sense in which these seemingly naive rules are the best possible.
One proposal is top-two probability sampling, which computes the two designs
with the highest posterior probability of being optimal, and then randomizes to
select among these two. One is a variant of top-two sampling which considers
not only the probability a design is optimal, but the expected amount by which
its quality exceeds that of other designs. The final algorithm is a modified
version of Thompson sampling that is tailored for identifying the best design.
We prove that these simple algorithms satisfy a sharp optimality property. In a
frequentist setting where the true quality of the designs is fixed, one hopes
the posterior definitively identifies the optimal design, in the sense that
that the posterior probability assigned to the event that some other design is
optimal converges to zero as measurements are collected. We show that under the
proposed algorithms this convergence occurs at an exponential rate, and the
corresponding exponent is the best possible among all allocation


title: Folding with Soergel bimodules

abstract:
  We give a gentle introduction to the concept of folding. That is, we provide
an elementary discussion of equivariant categories, their weighted Grothendieck
groups, and the technical aspects of computing with them. We then perform the
computations required to confirm that quasi-split Hecke algebras with unequal
parameters are categorified by equivariant Soergel bimodules, in almost every
case.


title: Objective Bayesian Analysis for the Lomax Distribution

abstract:
  In this paper we propose to make Bayesian inferences for the parameters of
the Lomax distribution using non-informative priors, namely the Jeffreys prior
and the reference prior. We assess Bayesian estimation through a Monte Carlo
study with 500 simulated data sets. To evaluate the possible impact of prior
specification on estimation, two criteria were considered: the bias and square
root of the mean square error. The developed procedures are illustrated on a
real data set.


title:
Ground truth? Concept-based communities versus the external
  classification of physics manuscripts

abstract:
  Community detection techniques are widely used to infer hidden structures
within interconnected systems. Despite demonstrating high accuracy on
benchmarks, they reproduce the external classification for many real-world
systems with a significant level of discrepancy. A widely accepted reason
behind such outcome is the unavoidable loss of non-topological information
(such as node attributes) encountered when the original complex system is
represented as a network. In this article we emphasize that the observed
discrepancies may also be caused by a different reason: the external
classification itself. For this end we use scientific publication data which i)
exhibit a well defined modular structure and ii) hold an expert-made
classification of research articles. Having represented the articles and the
extracted scientific concepts both as a bipartite network and as its unipartite
projection, we applied modularity optimization to uncover the inner thematic
structure. The resulting clusters are shown to partly reflect the author-made
classification, although some significant discrepancies are observed. A
detailed analysis of these discrepancies shows that they carry essential
information about the system, mainly related to the use of similar techniques
and methods across different (sub)disciplines, that is otherwise omitted when
only the external classification is considered.


title:
Volovik Effect and Fermi-Liquid Behavior in the s-Wave Superconductor
  CaPd2As2: 75As NMR-NQR Measurements

abstract:
  The electronic and magnetic properties of the collapsed-tetragonal
CaPd$_2$As$_2$ superconductor (SC) with a transition temperature of 1.27 K have
been investigated by $^{75}$As nuclear magnetic resonance (NMR) and nuclear
quadrupole resonance (NQR) measurements. The temperature ($T$) dependence of
the nuclear spin lattice relaxation rates (1/$T_1$) and the Knight shifts
indicate the absence of magnetic correlations in the normal state. In the SC
state, 1/$T_1$ measured by $^{75}$As NQR shows a clear Hebel-Slichter (HS) peak
just below $T_{\rm c}$ and decreases exponentially at lower $T$, confirming a
conventional $s$-wave SC. In addition, the Volovik effect, also known as
Doppler shift effect, has been clearly evidenced by the observation of the
suppression of the HS peak with applied magnetic field.


title:
Thermal noise and optomechanical features in the emission of a
  membrane-coupled compound cavity laser diode

abstract:
  We demonstrate the use of a compound optical cavity as linear displacement
detector, by measuring the thermal motion of a silicon nitride suspended
membrane acting as the external mirror of a near-infrared Littrow laser diode.
Fluctuations in the laser optical power induced by the membrane vibrations are
collected by a photodiode integrated within the laser, and then measured with a
spectrum analyzer. The dynamics of the membrane driven by a piezoelectric
actuator is investigated as a function of air pressure and actuator
displacement in a homodyne configuration. The high Q-factor ($\sim 3.4\cdot
10^4$ at $8.3 \cdot 10^{-3}$ mbar) of the fundamental mechanical mode at $\sim
73$ kHz guarantees a detection sensitivity high enough for direct measurement
of thermal motion at room temperature ($\sim 87$ pm RMS). The compound cavity
system here introduced can be employed as a table-top, cost-effective linear
displacement detector for cavity optomechanics. Furthermore, thanks to the
strong optical nonlinearities of the laser compound cavity, these systems open
new perspectives in the study of non-Markovian quantum properties at the
mesoscale.


title:
Persistent Directional Current at Equilibrium in Nonreciprocal Many-Body
  Near Field Electromagnetic Heat Transfer

abstract:
  We consider the consequence of nonreciprocity in near-field heat transfer by
studying systems consisting of magneto-optical nanoparticles.We demonstrate
that, in thermal equilibrium, a nonreciprocal many-body system in heat transfer
can support a persistent directional heat current, without violating the second
law of thermodynamics. Such a persistent directional heat current cannot occur
in reciprocal systems, and can only arise in many-body systems in heat
transfer. The use of nonreciprocity therefore points to a new regime of
near-field heat transfer for the control of heat flow in the nanoscale.


title:
MPAR: A Movement Pattern-Aware Optimal Routing for Social Delay Tolerant
  Networks

abstract:
  Social Delay Tolerant Networks (SDTNs) are a special kind of Delay Tolerant
Network (DTN) that consists of a number of mobile devices with social
characteristics. The current research achievements on routing algorithms tend
to separately evaluate the available profit for each prospective relay node and
cannot achieve the global optimal performance in an overall perspective. In
this paper, we propose a Movement Pattern-Aware optimal Routing (MPAR) for
SDTNs, by choosing the optimal relay node(s) set for each message, which
eventually based on running a search algorithm on a hyper-cube solution space.
Concretely, the movement pattern of a group of node(s) can be extracted from
the movement records of nodes. Then the set of commonly visited locations for
the relay node(s) set and the destination node is obtained, by which we can
further evaluate the co-delivery probability of the relay node(s) set. Both
local search scheme and tabu-search scheme are utilized in finding the optimal
set, and the tabu-search based routing Tabu-MPAR is proved able to guide the
relay node(s) set in evolving to the optimal one. We demonstrate how the MPAR
algorithm significantly outperforms the previous ones through extensive
simulations, based on the synthetic SDTN mobility model.


title: Epidemic Processes over Adaptive State-Dependent Networks

abstract:
  In this paper, we study the dynamics of epidemic processes taking place in
adaptive networks of arbitrary topology. We focus our study on the adaptive
susceptible-infected-susceptible (ASIS) model, where healthy individuals are
allowed to temporarily cut edges connecting them to infected nodes in order to
prevent the spread of the infection. In this paper, we derive a closed-form
expression for a lower bound on the epidemic threshold of the ASIS model in
arbitrary networks with heterogeneous node and edge dynamics. For networks with
homogeneous node and edge dynamics, we show that the resulting \blue{lower
bound} is proportional to the epidemic threshold of the standard SIS model over
static networks, with a proportionality constant that depends on the adaptation
rates. Furthermore, based on our results, we propose an efficient algorithm to
optimally tune the adaptation rates in order to eradicate epidemic outbreaks in
arbitrary networks. We confirm the tightness of the proposed lower bounds with
several numerical simulations and compare our optimal adaptation rates with
popular centrality measures.


title: Integral solutions to boundary quantum Knizhnik-Zamolodchikov equations

abstract:
  We construct integral representations of solutions to the boundary quantum
Knizhnik-Zamolodchikov equations. These are difference equations taking values
in tensor products of Verma modules of quantum affine $\mathfrak{sl}_2$, with
the K-operators acting diagonally. The integrands in question are products of
scalar-valued elliptic weight functions with vector-valued trigonometric weight
functions (boundary Bethe vectors). These integrals give rise to a basis of
solutions of the boundary qKZ equations over the field of quasi-constant
meromorphic functions in weight subspaces of the tensor product.


title: On the Number of Zeros and Poles of Dirichlet Series

abstract:
  This paper investigates lower bounds on the number of zeros and poles of a
general Dirichlet series in a disk of radius $r$ and gives, as a consequence,
an affirmative answer to an open problem of Bombieri and Perelli on the bound.
Applications will also be given to Picard type theorems, global estimates on
the symmetric difference of zeros, and uniqueness problems for Dirichlet
series.


title: Take up DNSSEC When Needed

abstract:
  The threats of caching poisoning attacks largely stimulate the deployment of
DNSSEC. Being a strong but demanding cryptographical defense, DNSSEC has its
universal adoption predicted to go through a lengthy transition. Thus the
DNSSEC practitioners call for a secure yet lightweight solution to speed up
DNSSEC deployment while offering an acceptable DNSSEC-like defense. This paper
proposes a new defense against cache poisoning attacks, still using but lightly
using DNSSEC. In the solution, DNS operates in the DNSSEC-oblivious mode unless
a potential attack is detected and triggers a switch to the DNSSEC-aware mode.
The performance of the defense is analyzed and validated. The modeling checking
results demonstrate that only a small DNSSEC query load is needed to ensure a
small enough cache poisoning success rate.


title: Discrete free Abelian central stabilizers in a higher order frame bundle

abstract:
  Let a real Lie group $G$ have a $C^\infty$ action on a real manifold $M$.
Assume every nontrivial element of $G$ has nowhere dense fixpoint set in $M$.
First, we show, in every frame bundle, except possibly the $0$th, that each
stabilizer admits no nontrivial compact subgroups. Second, we show that, if $G$
is connected, then there is a dense open $G$-invariant subset of some higher
order frame bundle of $M$ such that, for any point $x$ in that subset, the
stabilizer in $G$ of $x$ is a discrete, finitely-generated, free-Abelian,
central subgroup of $G$. We derive several corollaries of these two results.


title:
A One-Hop Information Based Geographic Routing Protocol for Delay
  Tolerant MANETs

abstract:
  Delay and Disruption Tolerant Networks (DTNs) may lack continuous network
connectivity. Routing in DTNs is thus a challenge since it must handle network
partitioning, long delays, and dynamic topology. Meanwhile, routing protocols
of the traditional Mobile Ad hoc NETworks (MANETs) cannot work well due to the
failure of its assumption that most network connections are available. In this
article, a geographic routing protocol is proposed for MANETs in delay tolerant
situations, by using no more than one-hop information. A utility function is
designed for implementing the under-controlled replication strategy. To reduce
the overheads caused by message flooding, we employ a criterion so as to
evaluate the degree of message redundancy. Consequently a message redundancy
coping mechanism is added to our routing protocol. Extensive simulations have
been conducted and the results show that when node moving speed is relatively
low, our routing protocol outperforms the other schemes such as Epidemic, Spray
and Wait, FirstContact in delivery ratio and average hop count, while
introducing an acceptable overhead ratio into the network.