title: Spatio-temporal patterns in ultra-slow domain wall creep dynamics

abstract:
  In presence of impurities, ferromagnetic and ferroelectric domain walls slide
only above a finite external field. Close to this depinning threshold, they
proceed by large and abrupt jumps, called avalanches, while, at much smaller
field, these interfaces creep by thermal activation. In this work we develop a
novel numerical technique that captures the ultra-slow creep regime over huge
time scales. We point out the existence of activated events that involve
collective reorganizations similar to avalanches, but, at variance with them,
display correlated spatio-temporal patterns that resemble the complex sequence
of aftershocks observed after a large earthquake. Remarkably, we show that
events assembly in independent clusters that display at large scales the same
statistics as critical depinning avalanches. We foresee this correlated
dynamics being experimentally accessible by magneto-optical imaging of
ferromagnetic films.


title: The Finiteness of vortices in steady incompressible viscous fluid flow

abstract:
  In this work, we provide two novel approaches to show that incompressible
fluid flow in a finite domain contains at most a finite number vortices. We use
a recently developed geometric theory of incompressible viscous flows along
with an existing mathematical analysis concept to establish the finiteness. We
also offer a second proof of finiteness by roping in the Kolmogorov's length
scale criterion in conjunction with the notion of diametric disks.


title: A generalized super integrable hierarchy of Dirac type

abstract:
  In this letter, a new generalized matrix spectral problem of Dirac type
associated with the super Lie algebra $\mathcal{B}(0,1)$ is proposed and its
corresponding super integrable hierarchy is constructed.


title: On $(2k+1, 2k+3)$-core partitions with distinct parts

abstract:
  In this paper, we are mainly concerned with the enumeration of $(2k+1,
2k+3)$-core partitions with distinct parts. We derive the number and the
largest size of such partitions, confirming two conjectures posed by Straub.


title: Internal Structure of Charged AdS Black Holes

abstract:
  When an electrically charged black hole is perturbed its inner horizon
becomes a singularity, often referred to as the Poisson-Israel mass inflation
singularity. Ori constructed a model of this phenomenon for asymptotically flat
black holes, in which the metric can be determined explicitly in the mass
inflation region. In this paper we implement the Ori model for charged AdS
black holes. We find that the mass function inflates faster than the flat space
case as the inner horizon is approached. Nevertheless, the mass inflation
singularity is still a weak singularity: although spacetime curvature becomes
infinite, tidal distortions remain finite on physical objects attempting to
cross it.


title:
Prevention of infectious diseases by public vaccination and individual
  protection

abstract:
  In the face of serious infectious diseases, governments endeavour to
implement containment measures such as public vaccination at a macroscopic
level. Meanwhile, individuals tend to protect themselves by avoiding contacts
with infections at a microscopic level. However, a comprehensive understanding
of how such combined strategy influences epidemic dynamics is still lacking. We
study a susceptible-infected-susceptible epidemic model with imperfect
vaccination on dynamic contact networks, where the macroscopic intervention is
represented by random vaccination of the population and the microscopic
protection is characterised by susceptible individuals rewiring contacts from
infective neighbours. In particular, the model is formulated both in
populations without and then with demographic effects. Using the pairwise
approximation and the probability generating function approach, we investigate
both dynamics of the epidemic and the underlying network. For populations
without demography, the emerging degree correlations, bistable states, and
oscillations demonstrate the combined effects of the public vaccination program
and individual protective behavior. Compared to either strategy in isolation,
the combination of public vaccination and individual protection is more
effective in preventing and controlling the spread of infectious diseases by
increasing both the invasion threshold and the persistence threshold. For
populations with additional demographic factors, the integration between
vaccination intervention and individual rewiring may promote epidemic spreading
due to the birth effect. Moreover, the degree distributions of both networks in
the steady state is closely related to the degree distribution of newborns,
which leads to uncorrelated connectivity. All the results demonstrate the
importance of both local protection and global intervention, as well as the
demographic effects.

categories: physics.soc-ph cs.SI nlin.AO physics.bio-ph q-bio.PE


title:
Sub-cycle control of terahertz high-harmonic generation by dynamical
  Bloch oscillations

abstract:
  Ultrafast charge transport in strongly biased semiconductors is at the heart
of highspeed electronics, electro-optics, and fundamental solid-state physics.
Intense light pulses in the terahertz (THz) spectral range have opened
fascinating vistas: Since THz photon energies are far below typical electronic
interband resonances, a stable electromagnetic waveform may serve as a
precisely adjustable bias. Novel quantum phenomena have been anticipated for
THz amplitudes reaching atomic field strengths. We exploit controlled THz
waveforms with peak fields of 72 MV/cm to drive coherent interband polarization
combined with dynamical Bloch oscillations in semiconducting gallium selenide.
These dynamics entail the emission of phase-stable high-harmonic transients,
covering the entire THz-to-visible spectral domain between 0.1 and 675 THz.
Quantum interference of different ionization paths of accelerated charge
carriers is controlled via the waveform of the driving field and explained by a
quantum theory of inter- and intraband dynamics. Our results pave the way
towards all-coherent THz-rate electronics.


title:
Contact inhibition of locomotion and mechanical cross-talk between
  cell-cell and cell-substrate adhesion determines the pattern of junctional
  tension in epithelial cell aggregates

abstract:
  We generated a computational approach to analyze the biomechanics of
epithelial cell aggregates, either island or stripes or entire monolayers, that
combines both vertex and contact-inhibition-of-locomotion models to include
both cell-cell and cell-substrate adhesion. Examination of the distribution of
cell protrusions (adhesion to the substrate) in the model predicted high order
profiles of cell organization that agree with those previously seen
experimentally. Cells acquired an asymmetric distribution of basal protrusions,
traction forces and apical aspect ratios that decreased when moving from the
edge to the island center. Our in silico analysis also showed that tension on
cell-cell junctions and apical stress is not homogeneous across the island.
Instead, these parameters are higher at the island center and scales up with
island size, which we confirmed experimentally using laser ablation assays and
immunofluorescence. Without formally being a 3-dimensional model, our approach
has the minimal elements necessary to reproduce the distribution of cellular
forces and mechanical crosstalk as well as distribution of principal stress in
cells within epithelial cell aggregates. By making experimental testable
predictions, our approach would benefit the mechanical analysis of epithelial
tissues, especially when local changes in cell-cell and/or cell-substrate
adhesion drive collective cell behavior.


title: DENSER Cities: A System for Dense Efficient Reconstructions of Cities

abstract:
  This paper is about the efficient generation of dense, colored models of
city-scale environments from range data and in particular, stereo cameras.
Better maps make for better understanding; better understanding leads to better
robots, but this comes at a cost. The computational and memory requirements of
large dense models can be prohibitive. We provide the theory and the system
needed to create city-scale dense reconstructions. To do so, we apply a
regularizer over a compressed 3D data structure while dealing with the complex
boundary conditions this induces during the data-fusion stage. We show that
only with these considerations can we swiftly create neat, large, "well
behaved" reconstructions. We evaluate our system using the KITTI dataset and
provide statistics for the metric errors in all surfaces created compared to
those measured with 3D laser. Our regularizer reduces the median error by 40%
in 3.4 km of dense reconstructions with a median accuracy of 6 cm. For
subjective analysis, we provide a qualitative review of 6.1 km of our dense
reconstructions in an attached video. These are the largest dense
reconstructions from a single passive camera we are aware of in the literature.


title:
Effect of hypertension on low-density lipoprotein transport within a
  multi-layered arterial wall: modelling consistent with experiments

abstract:
  The influence of hypertension on low-density lipoproteins intake into the
arterial wall is an important factor for understanding mechanisms of
atherosclerosis. It has been experimentally observed that the increased
pressure leads to the higher level of the LDL inside the wall. In this paper we
attempt to construct a model of the LDL transport which reproduces
quantitatively experimental outcomes. We supplement the well known four-layer
arterial wall model to include two pressure induced effects: the compression of
the intima tissue and the increase of the fraction of leaky junctions. We
demonstrate that such model can reach the very good agreement with experimental
data.


title: A Differentiable Transition Between Additive and Multiplicative Neurons

abstract:
  Existing approaches to combine both additive and multiplicative neural units
either use a fixed assignment of operations or require discrete optimization to
determine what function a neuron should perform. However, this leads to an
extensive increase in the computational complexity of the training procedure.
  We present a novel, parameterizable transfer function based on the
mathematical concept of non-integer functional iteration that allows the
operation each neuron performs to be smoothly and, most importantly,
differentiablely adjusted between addition and multiplication. This allows the
decision between addition and multiplication to be integrated into the standard
backpropagation training procedure.


title:
Emergence of fermionic finite-temperature critical point in a Kondo
  lattice

abstract:
  The underlying Dirac point is central to the profound physics manifested in a
wide class of materials. However, it is often difficult to drive a system with
Dirac points across the massless fermionic critical point. Here by exploiting
screening of local moments under spin-orbit interactions in a Kondo lattice, we
show that below the Kondo temperature, the Kondo lattice undergoes a
topological transition from a strong topological insulator to a weak
topological insulator at a finite temperature $T_D$. At $T_D$, massless Dirac
points emerge and the Kondo lattice becomes a Dirac semimetal. Our analysis
indicates that the emergent relativistic symmetry dictates non-trivial thermal
responses over large parameter and temperature regimes. In particular, it
yields critical scaling behaviors both in magnetic and transport responses near
$T_D$.


title: An explanation of one loop induced $h\to \mu \tau$ decay

abstract:
  We discuss a possibility to explain the excess of $h\to\mu\tau$ at one-loop
level. We introduce three generation of vector-like lepton doublet $L'$ and two
singlet scalars $S_{1,2}$ which are odd under $Z_2$, while all the standard
model fields are even under this discrete symmetry. We show that $S_1$ can be a
good dark matter candidate. We show that we can explain the dark matter relic
abundance, large part of the discrepancy of muon $g-2$ between experiments and
the standard model predictions, as well as the $h\to\mu\tau$ excess of $\sim 1$
%, while evading constraints from experiments of dark matter direct detection
and charged lepton flavor violating processes. We also consider prospects of
production of $S_2$ at LHC with energy $\sqrt{s}=14$ TeV.


title: Non-isometric T-duality from gauged sigma models

abstract:
  Local symmetries is one of the most successful themes in modern theoretical
physics. Although they are usually associated to Lie algebras, a gradual
increase of interest in more general situations where local symmetries are
associated to groupoids and algebroids has taken place in recent years. On the
other hand, dualities is another persistently interesting theme in modern
physics. One of the most prominent examples is provided by target space duality
in string theory. The latter, Abelian or not, is usually associated to the
presence of isometries, which is however a very restrictive assumption. In this
contribution we discuss some recent advances located at the intersection of the
above two themes. Focusing on bosonic string sigma models we discuss certain
gauged versions where (a) the invariance conditions on the background fields
are much milder than the isometric case and (b) the gauge symmetry is
generically associated to a Lie algebroid instead of just a Lie algebra.
Furthermore we utilize such gauged sigma models to study the possibility of
non-Abelian, non-isometric T-duality.


title:
The effect of realistic nuclear charge distributions on isotope shifts
  and towards the extraction of higher order nuclear radial moments

abstract:
  Background: Atomic spectral lines from different isotopes display a small
shift in energy, commonly referred to as the line isotope shift. One of the
components of the isotope shift is the field shift, which depends on the extent
and the shape of the nuclear charge density distribution. Purpose: To
investigate how sensitive field shifts are with respect to variations in the
nuclear size and shape and what information of nuclear charge distributions
that can be extracted from measured field shifts. Methods: Nuclear properties
are obtained from nuclear density functional theory calculations based on the
Skyrme-Hartree-Fock-Bogoliubov approach. These results are combined with
multiconfiguration Dirac-Hartree-Fock methods to obtain realistic field shifts.
Results: Phenomena such as nuclear deformation and variations in the
diffuseness of nuclear charge distributions give measurable contributions to
the field shifts. Using a novel approach, we demonstrate the possibility to
extract new information concerning the nuclear charge densities from the
observed field shifts. Conclusions: Combining methods used in atomic and
nuclear structure theory gives an improved description of field shifts.
Extracting additional nuclear information from measured field shifts is
possible in the near future with improved experimental methods.


title:
H\"older regularity for Maxwell's equations under minimal assumptions on
  the coefficients

abstract:
  We prove global H\"older regularity for the solutions to the time-harmonic
anisotropic Maxwell's equations, under the assumptions of H\"older continuous
coefficients. The regularity hypotheses on the coefficients are minimal. The
same estimates hold also in the case of bianisotropic material parameters.


title:
Some Permutationllay Symmetric Multiple Hypotheses Testing Rules Under
  Dependent Set up

abstract:
  In this paper, our interest is in the problem of simultaneous hypothesis
testing when the test statistics corresponding to the individual hypotheses are
possibly correlated. Specifically, we consider the case when the test
statistics together have a multivariate normal distribution (with equal
correlation between each pair) with an unknown mean vector and our goal is to
decide which components of the mean vector are zero and which are non-zero.
This problem was taken up earlier in Bogdan et al. (2011) for the case when the
test statistics are independent normals. Asymptotic optimality in a Bayesian
decision theoretic sense was studied in this context, the optimal precodures
were characterized and optimality of some well-known procedures were thereby
established. The case under dependence was left as a challenging open problem.
We have studied the problem both theoretically and through extensive
simulations and have given some permutation invariant rules. Though in Bogdan
et al. (2011), the asymptotic derivations were done in the context of sparsity
of the non-zero means, our result does not require the assumption of sparsity
and holds under a more general setup.


title: Three-body interaction of Rydberg slow light polaritons

abstract:
  We study a system of three photons in an atomic medium coupled to Rydberg
states near the conditions of electromagnetically induced transparency. Based
on the analytical analysis of the microscopic set of equations in the
far-detuned regime, the effective three-body interaction for these Rydberg
polaritons is derived. For slow light polaritons, we find a strong three-body
repulsion with the remarkable property that three polaritons can become
essentially non-interacting at short distances. This analysis allows us to
derive the influence of the three-body repulsion on bound states and
correlation functions of photons propagating through a one-dimensional atomic
cloud.


title: Variational Bayesian Inference of Line Spectra

abstract:
  In this paper, we address the fundamental problem of line spectral estimation
in a Bayesian framework. We target model order and parameter estimation via
variational inference in a probabilistic model in which the frequencies are
continuous-valued, i.e., not restricted to a grid; and the coefficients are
governed by a Bernoulli-Gaussian prior model turning model order selection into
binary sequence detection. Unlike earlier works which retain only point
estimates of the frequencies, we undertake a more complete Bayesian treatment
by estimating the posterior probability density functions (pdfs) of the
frequencies and computing expectations over them. Thus, we additionally capture
and operate with the uncertainty of the frequency estimates. Aiming to maximize
the model evidence, variational optimization provides analytic approximations
of the posterior pdfs and also gives estimates of the additional parameters. We
propose an accurate representation of the pdfs of the frequencies by mixtures
of von Mises pdfs, which yields closed-form expectations. We define the
algorithm VALSE in which the estimates of the pdfs and parameters are
iteratively updated. VALSE is a gridless, convergent method, does not require
parameter tuning, can easily include prior knowledge about the frequencies and
provides approximate posterior pdfs based on which the uncertainty in line
spectral estimation can be quantified. Simulation results show that accounting
for the uncertainty of frequency estimates, rather than computing just point
estimates, significantly improves the performance. The performance of VALSE is
superior to that of state-of-the-art methods and closely approaches the
Cram\'er-Rao bound computed for the true model order.


title:
The resonant boundary $Q$-curvature problem and boundary-weighted
  barycenters

abstract:
  Given a compact four-dimensional Riemannian manifold $(M, g)$ with boundary,
we study the problem of existence of Riemannian metrics on $M$ conformal to $g$
with prescribed $Q$-curvature in the interior $\mathring{M}$ of $M$, and zero
$T$-curvature and mean curvature on the boundary $\partial M$ of $M$. This
geometric problem is equivalent to solving a fourth-order elliptic boundary
value problem (BVP) involving the Paneitz operator with boundary conditions of
Chang-Qing and Neumann operators. The corresponding BVP has a variational
formulation but the corresponding variational problem, in the case under study,
is not compact. To overcome such a difficulty we perform a systematic study,
\`a la Bahri, of the so called {\it critical points at infinity}, compute their
Morse indices, determine their contribution to the difference of topology
between the sublevel sets of associated Euler-Lagrange functional and hence
extend the full Morse Theory to this noncompact variational problem. To
establish Morse inequalities we were led to investigate from the topological
viewpoint the space of boundary-weighted barycenters of the underlying
manifold, which arise in the description of the topology of very negative
sublevel sets of the related functional. As an application of our approach we
derive various existence results and provide a Poincar\'e-Hopf type criterium
for the prescribed $Q$-curvature problem on compact four dimensional Riemannian
manifolds with boundary.


title: Radiation-induced segregation in dilute Re-W solid solutions

abstract:
  The occurrence of segregation in highly dilute alloys under irradiation is an
unusual phenomenon that has so far eluded theoretical explanation. Using ab
initio calculations, we are able to explain the origin of radiation-induced
rhenium segregation in dilute tungsten-rhenium alloys.


title: Behavior of Self-Motivated Agents in Complex Networks

abstract:
  Traditional evolutionary game theory describes how certain strategy spreads
throughout the system where individual player imitates the most successful
strategy among its neighborhood. Accordingly, player doesn't have own authority
to change their state. However in the human society, peoples do not just follow
strategies of other people, they choose their own strategy. In order to see the
decision of each agent in timely basis and differentiate between network
structures, we conducted multi-agent based modeling and simulation. In this
paper, agent can decide its own strategy by payoff comparison and we name this
agent as "Self-motivated agent". To explain the behavior of self-motivated
agent, prisoner's dilemma game with cooperator, defector, loner and punisher
are considered as an illustrative example. We performed simulation by
differentiating participation rate, mutation rate and the degree of network,
and found the special coexisting conditions.


title: How different are the Li\`ege and Hamburg atlases of the solar spectrum?

abstract:
  Context: The high-fidelity solar spectral atlas prepared by Delbouille and
co-workers (Li\`ege atlas), and the one by Neckel and co-workers (Hamburg
atlas), are widely recognised as the most important reference spectra of the
Sun at disc-centre in the visible wavelength range. Both datasets serve as
fundamental resources for many researchers, in particular for chemical
abundance analysis. But despite their similar published specifications
(spectral resolution, noise level), the shapes of spectral lines in the two
atlases differ significantly and systematically.
  Aims: Knowledge of any instrumental degradations is imperative to fully
exploit the information content of spectroscopic data. We seek to investigate
the magnitude---and to explain the possible sources---of these differences. We
provide the wavelength-dependent correction parameters that need to be taken
into account when the spectra are to be compared with e.g. synthetic data.
  Methods: A parametrically degraded version of the Hamburg spectrum is fitted
to the Li\`ege spectrum. The parameters of the model (wavelength shift,
broadening, intensity scaling, intensity offset) represent the different
characteristics of the respective instruments, observational strategies and
data processing.
  Results: The wavelength scales of the Li\`ege and Hamburg atlases differ on
average by 0.5 m{\AA} with a standard deviation of $\pm$2 m{\AA}, except for a
peculiar region around 5500 {\AA}. The continuum levels are offset by up to 18%
below 5000 {\AA} but stably at a 0.8% difference towards the red. We find no
evidence for spectral straylight in the Li\`ege spectrum. Its resolving power
is almost independent of wavelength but limited to about 216000, between two to
six times less than specified. When accounting for the degradations determined
in this work, the spectra of the two atlases agree within a few parts in
10$^3$.


title: The thermodynamic cost of quantum operations

abstract:
  The amount of heat generated by computers is rapidly becoming one of the main
problems for developing new generations of information technology. The
thermodynamics of computation sets the ultimate physical bounds on heat
generation. A lower bound is set by the Landauer Limit, at which computation
becomes thermodynamically reversible. For classical computation there is no
physical principle which prevents this limit being reached, and approaches to
it are already being experimentally tested. In this paper we show that for
quantum computation there is an unavoidable excess heat generation that renders
it inherently thermodynamically irreversible. The Landauer Limit cannot, in
general, be reached by quantum computers. We show the existence of a lower
bound to the heat generated by quantum computing that exceeds that given by the
Landauer Limit, give the special conditions where this excess cost may be
avoided, and show how classical computing falls within these special
conditions.


title:
Statistical fluctuations in pedestrian evacuation times and the effect
  of social contagion

abstract:
  Mathematical models of pedestrian evacuation and the associated simulation
software have become essential tools for the assessment of the safety of public
facilities and buildings. While a variety of models are now available, their
calibration and test against empirical data are generally restricted to global,
averaged quantities, the statistics compiled from the time series of individual
escapes (" microscopic " statistics) measured in recent experiments are thus
overlooked. In the same spirit, much research has primarily focused on the
average global evacuation time, whereas the whole distribution of evacuation
times over some set of realizations should matter. In the present paper we
propose and discuss the validity of a simple relation between this distribution
and the " microscopic " statistics, which is theoretically valid in the absence
of correlations. To this purpose, we develop a minimal cellular automaton, with
novel features that afford a semi-quantitative reproduction of the experimental
" microscopic " statistics. We then introduce a process of social contagion of
impatient behavior in the model and show that the simple relation under test
may dramatically fail at high contagion strengths, the latter being responsible
for the emergence of strong correlations in the system. We conclude with
comments on the potential practical relevance for safety science of
calculations based on " microscopic " statistics.


title:
The 154 MHz radio sky observed by the Murchison Widefield Array: noise,
  confusion and first source count analyses

abstract:
  We analyse a 154 MHz image made from a 12 h observation with the Murchison
Widefield Array (MWA) to determine the noise contribution and behaviour of the
source counts down to 30 mJy. The MWA image has a bandwidth of 30.72 MHz, a
field-of-view within the half-power contour of the primary beam of 570 deg^2, a
resolution of 2.3 arcmin and contains 13,458 sources above 5 sigma. The rms
noise in the centre of the image is 4-5 mJy/beam. The MWA counts are in
excellent agreement with counts from other instruments and are the most precise
ever derived in the flux density range 30-200 mJy due to the sky area covered.
Using the deepest available source count data, we find that the MWA image is
affected by sidelobe confusion noise at the ~3.5 mJy/beam level, due to
incompletely-peeled and out-of-image sources, and classical confusion becomes
apparent at ~1.7 mJy/beam. This work highlights that (i) further improvements
in ionospheric calibration and deconvolution imaging techniques would be
required to probe to the classical confusion limit and (ii) the shape of
low-frequency source counts, including any flattening towards lower flux
densities, must be determined from deeper ~150 MHz surveys as it cannot be
directly inferred from higher frequency data.


title:
Identities for the arctangent function by enhanced midpoint integration
  and the high-accuracy computation of pi

abstract:
  We describe a method of integration to obtain identities of the arctangent
function and show how this method can be applied to the high-accuracy
computation of the constant pi using the equation $\pi = 4 \arctan \left( 1
\right)$. Our approach combines the midpoint method with the Taylor expansion
series to enhance accuracy in the subintervals. The accuracy of this method of
integration is determined by number of subintervals $L$ and by order of the
Taylor expansion $M$. This approach provides significant flexibility in
computation since the required convergence in resulting equations can be
optimized through appropriate choices for the integers $L$ and $M$. Sample
computations are presented to illustrate that even with relatively small values
of the integers $L$ and $M$ the constant $\pi$ can be computed with high
accuracy.


title: The origin of the Frey elliptic curve in a too narrow margin

abstract:
  It is shown that an appropriate use of so-called double equations by
Diophantus provides the origin of the Frey elliptic curve and from it we can
deduce an elementary proof of Fermat's Last Theorem.


title: Scaling limit of the odometer in divisible sandpiles

abstract:
  In a recent work Levine et al. (2015) prove that the odometer function of a
divisible sandpile model on a finite graph can be expressed as a shifted
discrete bilaplacian Gaussian field. For the discrete torus, they suggest the
possibility that the scaling limit of the odometer may be related to the
continuum bilaplacian field. In this work we show that in any dimension the
rescaled odometer converges to the continuum bilaplacian field on the unit
torus.


title: VConv-DAE: Deep Volumetric Shape Learning Without Object Labels

abstract:
  With the advent of affordable depth sensors, 3D capture becomes more and more
ubiquitous and already has made its way into commercial products. Yet,
capturing the geometry or complete shapes of everyday objects using scanning
devices (e.g. Kinect) still comes with several challenges that result in noise
or even incomplete shapes. Recent success in deep learning has shown how to
learn complex shape distributions in a data-driven way from large scale 3D CAD
Model collections and to utilize them for 3D processing on volumetric
representations and thereby circumventing problems of topology and
tessellation. Prior work has shown encouraging results on problems ranging from
shape completion to recognition. We provide an analysis of such approaches and
discover that training as well as the resulting representation are strongly and
unnecessarily tied to the notion of object labels. Thus, we propose a full
convolutional volumetric auto encoder that learns volumetric representation
from noisy data by estimating the voxel occupancy grids. The proposed method
outperforms prior work on challenging tasks like denoising and shape
completion. We also show that the obtained deep embedding gives competitive
performance when used for classification and promising results for shape
interpolation.


title: Quantum groups from stationary matrix models

abstract:
  We study the quantum groups appearing via models $C(G)\subset M_K(C(X))$
which are "stationary", in the sense that the Haar integration over $G$ is the
functional $tr\otimes\int_X$. Our results include a number of generalities,
notably with a substantial list of examples, and a detailed discussion in the
quantum permutation group case.


title: Chiron: A Robust Recommendation System with Graph Regularizer

abstract:
  Recommendation systems have been widely used by commercial service providers
for giving suggestions to users. Collaborative filtering (CF) systems, one of
the most popular recommendation systems, utilize the history of behaviors of
the aggregate user-base to provide individual recommendations and are effective
when almost all users faithfully express their opinions. However, they are
vulnerable to malicious users biasing their inputs in order to change the
overall ratings of a specific group of items. CF systems largely fall into two
categories - neighborhood-based and (matrix) factorization-based - and the
presence of adversarial input can influence recommendations in both categories,
leading to instabilities in estimation and prediction. Although the robustness
of different collaborative filtering algorithms has been extensively studied,
designing an efficient system that is immune to manipulation remains a
significant challenge. In this work we propose a novel "hybrid" recommendation
system with an adaptive graph-based user/item similarity-regularization -
"Chiron". Chiron ties the performance benefits of dimensionality reduction
(through factorization) with the advantage of neighborhood clustering (through
regularization). We demonstrate, using extensive comparative experiments, that
Chiron is resistant to manipulation by large and lethal attacks.


title: The Existence of the Tau One-Way Functions Class as a Proof that P != NP

abstract:
  We prove that P != NP by proving the existence of a class of functions we
call Tau, each of whose members satisfies the conditions of one-way functions.
Each member of Tau is a function computable in polynomial time, with negligible
probability of finding its inverse by any polynomial probabilistic algorithm.
We also prove that no polynomial-time algorithm exists to compute the inverse
of members of Tau, and that the problem of computing the inverse of Tau cannot
be reduced to FSAT in polynomial time.


title: Weak stability of the plasma-vacuum interface problem

abstract:
  We consider the free boundary problem for the two-dimensional plasma-vacuum
interface in ideal compressible magnetohydrodynamics (MHD). In the plasma
region, the flow is governed by the usual compressible MHD equations, while in
the vacuum region we consider the Maxwell system for the electric and the
magnetic fields. At the free interface, driven by the plasma velocity, the
total pressure is continuous and the magnetic field on both sides is tangent to
the boundary.
  We study the linear stability of rectilinear plasma-vacuum interfaces by
computing the Kreiss-Lopatinskii determinant of an associated linearized
boundary value problem. Apart from possible resonances, we obtain that the
piecewise constant plasma-vacuum interfaces are always weakly linearly stable,
independently of the size of tangential velocity, magnetic and electric fields
on both sides of the characteristic discontinuity.
  We also prove that solutions to the linearized problem obey an energy
estimate with a loss of regularity with respect to the source terms, both in
the interior domain and on the boundary, due to the failure of the uniform
Kreiss-Lopatinskii condition, as the Kreiss-Lopatinskii determinant associated
with this linearized boundary value problem has roots on the boundary of the
frequency space. In the proof of the a priori estimates, a crucial part is
played by the construction of symmetrizers for a reduced differential system,
which has poles at which the Kreiss-Lopatinskii condition may fail
simultaneously.


title:
Multiple-stage structure transformation of organic-inorganic hybrid
  perovskite CH3NH3PbI3

abstract:
  By performing spatially resolved Raman and photoluminescence spectroscopy
with varying excitation wavelength, density, and data acquisition parameters,
we have achieved a unified understanding towards the spectroscopy signatures of
the organic-inorganic hybrid perovskite, transforming from the pristine state
(CH3NH3PbI3) to fully degraded state (i.e., PbI2) for samples with varying
crystalline domain size from mesoscopic scale (approximately 100 nm) to
macroscopic size (cm), synthesized by three different techniques. We show that
the hybrid perovskite exhibits multiple stages of structure transformation
occurring either spontaneously or under light illumination, with exceptionally
high sensitivity to the illumination conditions (e.g., power, illumination time
and interruption pattern). We highlight four transformation stages (Stage 1 -
4, with Stage 1 being the pristine state) along a primary structure degradation
path exhibiting distinctly different Raman spectroscopy features at each stage,
and point out that previously reported Raman spectra in the literature reflect
degraded structures of either Stage 3 or 4. Additional characteristic optical
features of partially degraded materials under the joint action of spontaneous
and photo degradation are given. This study offers reliable benchmark results
for understanding the intrinsic material properties and structure
transformation of this unique category of hybrid materials, and a
straightforward method to monitor the structure degradation after the material
is used in a device or characterized by other techniques. The findings are
pertinently important to a wide range of potential applications where the
hybrid material is expected to function in greatly different environment and
light-matter interaction conditions.


title:
A global analysis of two-body D to VP decays within the framework of
  flavor symmetry

abstract:
  Two-body charmed meson decays $D\to VP$ are studied within the framework of
the diagrammatic approach. Under flavor SU(3) symmetry, all the flavor
amplitude sizes and their associated strong phases are extracted by performing
a $\chi^2$ fit. Thanks to the recent measurement of $D_s^+\to\pi^+\rho^0$, the
magnitudes and the strong phases of the $W$-annihilation amplitudes $A_{P,V}$
have been extracted for the first time. As a consequence, the branching
fractions of all the $D\to VP$ decays are predicted, especially those modes
that could not be predicted previously due to the unknown $A_{P,V}$. Our
working assumption, the flavor SU(3) symmetry, is tested by comparing our
predictions with experiment for the singly and doubly Cabibbo-suppressed decay
modes based on the flavor amplitudes extracted from the Cabibbo-favored decays
using the current data. The predictions for the doubly Cabibbo-suppressed
channels are in good agreement with the data, while those for the singly
Cabibbo-suppressed decay modes are seen to have flavor SU(3) symmetry breaking
effects. We find that the inclusion of SU(3) symmetry breaking in color-allowed
and color-suppressed tree amplitudes is needed in general in order to have a
better agreement with experiment. Nevertheless, the exact flavor
SU(3)-symmetric approach alone is adequate to provide an overall explanation
for the current data.


title:
On the Hausdorff measure of non-compactness for the parametrized
  Prokhorov metric

abstract:
  We quantify Prokhorov's Theorem by establishing an explicit formula for the
Hausdorff measure of non-compactness (HMNC) for the parametrized Prokhorov
metric on the set of Borel probability measures on a Polish space. Furthermore,
we quantify the Arzel\`a-Ascoli Theorem by obtaining upper and lower estimates
for the HMNC for the uniform norm on the space of continuous maps of a compact
interval into Euclidean N-space, using Jung's Theorem on the Chebyshev radius.
Finally, we combine the obtained results to quantify the stochastic
Arzel\`a-Ascoli Theorem by providing upper and lower estimates for the HMNC for
the parametrized Prokhorov metric on the set of multivariate continuous
stochastic processes.


title:
A General Distributed Dual Coordinate Optimization Framework for
  Regularized Loss Minimization

abstract:
  In modern large-scale machine learning applications, the training data are
often partitioned and stored on multiple machines. It is customary to employ
the "data parallelism" approach, where the aggregated training loss is
minimized without moving data across machines. In this paper, we introduce a
novel distributed dual formulation for regularized loss minimization problems
that can directly handle data parallelism in the distributed setting. This
formulation allows us to systematically derive dual coordinate optimization
procedures, which we refer to as Distributed Alternating Dual Maximization
(DADM). The framework extends earlier studies described in (Boyd et al., 2011;
Ma et al., 2015a; Jaggi et al., 2014; Yang, 2013) and has rigorous theoretical
analyses. Moreover with the help of the new formulation, we develop the
accelerated version of DADM (Acc-DADM) by generalizing the acceleration
technique from (Shalev-Shwartz and Zhang, 2014) to the distributed setting. We
also provide theoretical results for the proposed accelerated version and the
new result improves previous ones (Yang, 2013; Ma et al., 2015a) whose runtimes
grow linearly on the condition number. Our empirical studies validate our
theory and show that our accelerated approach significantly improves the
previous state-of-the-art distributed dual coordinate optimization algorithms.


title: Two-sided Matching Based Cooperative Spectrum Sharing

abstract:
  Dynamic spectrum access (DSA) can effectively improve the spectrum efficiency
and alleviate the spectrum scarcity, by allowing unlicensed secondary users
(SUs) to access the licensed spectrum of primary users (PUs) opportunistically.
Cooperative spectrum sharing is a new promising paradigm to provide necessary
incentives for both PUs and SUs in dynamic spectrum access. The key idea is
that SUs relay the traffic of PUs in exchange for the access time on the PUs'
licensed spectrum. In this paper, we formulate the cooperative spectrum sharing
between multiple PUs and multiple SUs as a two-sided market, and study the
market equilibrium under both complete and incomplete information. First, we
characterize the sufficient and necessary conditions for the market
equilibrium. We analytically show that there may exist multiple market
equilibria, among which there is always a unique Pareto-optimal equilibrium for
PUs (called PU-Optimal-EQ), in which every PU achieves a utility no worse than
in any other equilibrium. Then, we show that under complete information, the
unique Pareto-optimal equilibrium PU-Optimal-EQ can always be achieved despite
the competition among PUs; whereas, under incomplete information, the
PU-Optimal-EQ may not be achieved due to the mis-representations of SUs (in
reporting their private information). Regarding this, we further study the
worse-case equilibrium for PUs, and characterize a Robust equilibrium for PUs
(called PU-Robust-EQ), which provides every PU a guaranteed utility under all
possible mis-representation behaviors of SUs. Numerical results show that in a
typical network where the number of PUs and SUs are different, the performance
gap between PU-Optimal-EQ and PU-Robust-EQ is quite small (e.g., less than 10%
in the simulations).


title:
Excitation and reception of pure shear horizontal waves by using
  face-shear d24 mode piezoelectric wafers

abstract:
  The fundamental shear horizontal (SH0) wave in plate-like structures is of
great importance in non-destructive testing (NDT) and structural health
monitoring (SHM) as it is non-dispersive, while excitation and reception of SH0
waves using piezoelectrics is always a challenge. In this work, we firstly
demonstrate via finite element simulations that face-shear piezoelectrics is
superior to thickness-shear piezoelectrics in driving SH waves. Next, by using
a newly defined face-shear d24 PZT wafer as actuator and face-shear d36 PMN-PT
wafers as sensors, pure SH0 wave was successfully excited in an aluminum plate
from 140 kHz to 190 kHz. Then, it was shown that the face-shear d24 PZT wafer
could receive the SH0 wave only and filter the Lamb waves over a wide frequency
range (120 kHz to 230 kHz). The directionality of the excited SH0 wave was also
investigated using face-shear d24 PZT wafers as both actuators and sensors.
Results show that pure SH0 wave can be excited symmetrically along two
orthogonal directions (0{\deg} and 90{\deg} ) and the amplitude of the excited
SH0 wave can keep over 90% of the maximum amplitude when the deviate angle is
within 30{\deg}. This work could greatly promote the applications of SH waves
in NDT and SHM.


title:
Femtosecond THz time domain spectroscopy at 36 kHz scan rate using an
  acousto-optic delay

abstract:
  We present a rapid-scan, time-domain terahertz spectrometer employing
femtosecond Er:fiber technology and an acousto-optic delay with attosecond
precision, enabling scanning of terahertz transients over a 12.4 ps time window
at a waveform refresh rate of 36 kHz, and a signal-to-noise ratio of $1.7
\times 10^5/\sqrt{\rm Hz}$. Our approach enables real-time monitoring of
dynamic THz processes at unprecedented speeds, which we demonstrate through
rapid 2D thickness mapping of a spinning teflon disc at a precision of $10\,\rm
nm/\sqrt{\rm Hz}$. The compact, all-optical design ensures alignment-free
operation even in harsh environments.


title: Granular topological insulators

abstract:
  Granular conductors form an artificially engineered class of solid state
materials wherein the microstructure can be tuned to mimic a wide range of
otherwise inaccessible physical systems. At the same time, topological
insulators (TIs) have become a cornerstone of modern condensed matter physics
as materials hosting metallic states on the surface and insulating in the bulk.
However it remains to be understood how granularity affects this new and exotic
phase of matter. We perform electrical transport experiments on highly granular
topological insulator thin films of Bi$_2$Se$_3$ and reveal remarkable
properties. We observe clear signatures of topological surface states despite
granularity with distinctly different properties from conventional bulk TI
systems including sharp surface state coupling-decoupling transitions, large
surface state penetration depths and exotic Berry phase effects. We present a
model which explains these results. Our findings illustrate that granularity
can be used to engineer designer TIs, at the same time allowing easy access to
the Dirac-fermion physics that is inaccessible in single crystal systems.


title:
Real-time observation of interfering crystal electrons in high-harmonic
  generation

abstract:
  Accelerating and colliding particles has been a key strategy to explore the
texture of matter. Strong lightwaves can control and recollide electronic
wavepackets, generating high-harmonic (HH) radiation which encodes the
structure and dynamics of atoms and molecules and lays the foundations of
attosecond science. The recent discovery of HH generation in bulk solids
combines the idea of ultrafast acceleration with complex condensed matter
systems and sparks hope for compact solid-state attosecond sources and
electronics at optical frequencies. Yet the underlying quantum motion has not
been observable in real time. Here, we study HH generation in a bulk solid
directly in the time-domain, revealing a new quality of strong-field
excitations in the crystal. Unlike established atomic sources, our solid emits
HH radiation as a sequence of subcycle bursts which coincide temporally with
the field crests of one polarity of the driving terahertz waveform. We show
that these features hallmark a novel non-perturbative quantum interference
involving electrons from multiple valence bands. The results identify key
mechanisms for future solid-state attosecond sources and next-generation
lightwave electronics. The new quantum interference justifies the hope for
all-optical bandstructure reconstruction and lays the foundation for possible
quantum logic operations at optical clock rates.


title: Compact pentaquark structures

abstract:
  We study the possibility that at least one of the two pentaquark structures
recently reported by LHCb can be described as a compact pentaquark state, and
we give predictions for new channels that can be studied by the
experimentalists if this hypothesis is correct. We use very general arguments
dictated by symmetry considerations, in order to describe the pentaquark states
within a group theory approach. A complete classification of all possible
states and quantum numbers, that can be useful both to the experimentalists,
for new finding, or to theoretical model builders, are given, without the
introduction of any particular dynamical model. Some prediction are finally
given using a Guersey-Radicati inspired mass formula. We reproduce the mass and
the quantum numbers of the lightest pentaquark state reported by LHCb ( 3/2^-),
with a parameter free mass formula, fixed on the well established baryons. We
predict others pentaquark resonances (giving their masses, and suggesting
possible decay channels) which belong to the same multiplet of the lightest
one.Finally, we compute the partial decay widths for all the predicted
pentaquark resonances.


title: $BCCB$ complex Hadamard matrices of order 9, and MUBs

abstract:
  A new type of complex Hadamard matrices of order 9 are constructed. The
studied matrices are symmetric, block circulant with circulant blocks ($BCCB$)
and form an until now unknown non-reducible and non-affine two-parameter orbit.
Several suborbits are identified, including a one-parameter intersection with
the Fourier orbit $F_{9}^{(4)}$. The defect of this new type of Hadamard
matrices is observed to vary, from a generic value 2 to the anomalous values 4
and 10 for some sub-orbits, and to 12 and 16 for some single matrices. The
latter matrices are shown to be related to complete sets of MUBs in dimension
9.


title:
Terahertz Spin-Orbital Excitations in the paramagnetic state of
  multiferroic Sr$_2$FeSi$_2$O$_7$

abstract:
  We studied the novel multiferroic material Sr$_2$FeSi$_2$O$_7$, and found 3
absorption modes above the magnetic ordering transition temperature using
time-domain terahertz spectroscopy. These absorption modes can be explained as
the optical transitions between the spin-orbit coupling and crystal field split
3d$^6$ Fe$^{2+}$ ground state term in this material. Consideration of the
compressed tetrahedral environment of the Fe$^{2+}$ site is crucial to
understand the excitations. We point out, however, discrepancies between the
single-site atomic picture and the experimental results.


title: Black hole collapse and democratic models

abstract:
  We study the evolution of black hole entropy and temperature in collapse
scenarios, finding three generic lessons. First, entropy evolution is
extensive. Second, at large times, entropy and temperature ring with twice the
frequency of the lowest quasinormal mode. Third, the entropy oscillations
saturate black hole area theorems in general relativity. The first two features
are characteristic of entanglement dynamics in `democratic' models. Solely
based on general relativity and Bekenstein-Hawking entropy formula, our results
point to democratic models as microscopic theories of black holes. The third
feature can be taken as a prediction for democratic models coming from black
hole physics.


title: Rational Verification in Iterated Electric Boolean Games

abstract:
  Electric boolean games are compact representations of games where the players
have qualitative objectives described by LTL formulae and have limited
resources. We study the complexity of several decision problems related to the
analysis of rationality in electric boolean games with LTL objectives. In
particular, we report that the problem of deciding whether a profile is a Nash
equilibrium in an iterated electric boolean game is no harder than in iterated
boolean games without resource bounds. We show that it is a PSPACE-complete
problem. As a corollary, we obtain that both rational elimination and rational
construction of Nash equilibria by a supervising authority are PSPACE-complete
problems.


title: Matrix-Product Complementary dual Codes

abstract:
  Linear complementary dual codes (LCD) are linear codes satisfying $C\cap
C^{\perp}=\{0\}$. Under suitable conditions, matrix-product codes that are
complementary dual codes are characterized. We construct LCD codes using
quasi-orthogonal matrices. Some asymptotic results are derived.


title: Non-isothermal effects on Be disks

abstract:
  In the last decade, the viscous decretion disk model has emerged as the new
paradigm for Be star disks. In this contribution, we propose a simple
analytical model to estimate the continuum infrared excess arising from these
circumstellar disks, in the light of the currently accepted scenario. We
demonstrate that the disk can be satisfactorily described by a two component
system: an inner optically thick region, which we call the pseudo-photosphere,
and a diffuse outer part. In particular, a direct connexion between the disk
brightness profile and the thermal structure is derived, and then confronted to
realistic numerical simulations. This result quantifies how the
non-isothermality of the disk ultimately affects both infrared measured fluxes
and visibilities.


title:
Detecting a Structural Change in Functional Time Series Using Local
  Wilcoxon Statistic

abstract:
  Functional data analysis (FDA) is a part of modern multivariate statistics
that analyses data providing information about curves, surfaces or anything
else varying over a certain continuum. In economics and empirical finance we
often have to deal with time series of functional data, where we cannot easily
decide, whether they are to be considered as homogeneous or heterogeneous. At
present a discussion on adequate tests of homogenity for functional data is
carried. We propose a novel statistic for detetecting a structural change in
functional time series based on a local Wilcoxon statistic induced by a local
depth function proposed by Paindaveine and Van Bever (2013).


title: Bosonic Josephson effect in the Fano-Anderson model

abstract:
  We investigate the coherent dynamics of a non-interacting Bose-Einstein
condensate in a system consisting of two bosonic reservoirs coupled via a
spatially localized mode. We describe this system by a two-terminal
Fano-Anderson model and investigate analytically the time evolution of
observables such as the bosonic Josephson current. In doing so, we find that
the Josephson current sensitively depends on the on-site energy of the
localized mode. This facilitates to use this setup as a transistor for a
Bose-Einstein condensate. We identify two regimes. In one regime, the system
exhibits well-behaved long-time dynamics with a slowly oscillating and undamped
Josephson current. In a second regime, the Josephson current is a superposition
of an extremely weakly damped slow oscillation and an undamped fast
oscillation. Our results are confirmed by finite-size simulations.


title: Elementary knot theory

abstract:
  The aim of this survey article is to highlight several notoriously
intractable problems about knots and links, as well as to provide a brief
discussion of what is known about them.


title:
Applying universal scaling laws to identify the best molecular design
  paradigms for third-order nonlinear optics

abstract:
  The scaling of the fundamental limits of the second hyperpolarizability is
used to define the intrinsic second hyperpolarizability, which aids in
identifying material classes with ultralarge nonlinear-optical response per
unit of molecular size. The intrinsic nonlinear response is a size-independent
metric that we apply to comparing classes of molecular homologues, which are
made by adding repeat units to extend their lengths. Several new figures of
merit are proposed that quantify not only the intrinsic nonlinear response, but
also how the second hyperpolarizability increases with size within a molecular
class. Scaling types can be classified into sub-scaling, nominal scaling that
follows the theory of limits, and super-scaling behavior. Super-scaling
homologues that have large intrinsic nonlinearity are the most promising
because they efficiently take advantage of increased size. We apply our
approach to data in the literature to identify the best super-scaling molecular
paradigms and articulate the important underlying parameters.


title: A Broadband Micro-machined Far-Infrared Absorber

abstract:
  The experimental investigation of a broadband far-infrared meta-material
absorber is described. The observed absorptance is $>\,0.95$ from ${\rm
1-20\,THz}$ (${\rm 300-15\,\mu m}$) over a temperature range spanning ${\rm
5-300\,K}$. The meta-material, realized from an array of tapers ${\rm \approx
100\,\mu m}$ in length, is largely insensitive to the detailed geometry of
these elements and is cryogenically compatible with silicon-based
micro-machined technologies. The electromagnetic response is in general
agreement with a physically motivated transmission line model.


title:
Stabilization with residual-free bubbles for advection-dominated
  transport equations

abstract:
  An improved numerical scheme is proposed for advection-dominated
advection-diffusion problem. The scheme is based on Galerkin finite element
method (FEM) with basis enriched with approximations to residual-free bubbles.
The stabilisation effect of the numerical scheme was studied on several
benchmark problems with high-Peclet numbers. Comparison to traditional hp-FEM,
reveals improved stability and computational performance.


title: Meson electro-/photo-production from QCD

abstract:
  I present the calculation of the $\pi^+\gamma^\star\to\pi^+\pi^0$ transition
amplitude from quantum chromodynamics performed by the Hadron Spectrum
Collaboration. The amplitude is determined for a range of values of the photon
virtuality and the final state energy. One observes a clear dynamical
enhancement due to the presence of the $\rho$ resonance. By fitting the
transition amplitude and analytically continuing it onto the $\rho$-pole, the
$\rho\to\pi\gamma^\star$ form factor is obtained. This exploratory calculation,
performed using lattice quantum chromodynamics, constitutes the very first
determination of an electroweak decay of a hadronic resonance directly from the
fundamental theory of quarks and gluons. In this talk, I highlight some of the
necessary steps that made this calculation possible, placing emphasis on
recently developed formalism. Finally, I discuss the status and outlook of the
field for the study of $N\gamma^\star\to N^\star\to N\pi$ transitions.


title:
Nonstandard transition GUE-GOE for random matrices and spectral
  statistics of graphene nanoflakes

abstract:
  Spectral statistics of weakly-disordered triangular graphene flakes with
zigzag edges are revisited. Earlier, we have found numerically that such
systems may shown spectral fluctuations of GUE, signalling the time-reversal
symmetry breaking at zero magnetic field, accompanied by approximate twofold
valley degeneracy of each energy level [Phys. Rev. B 85, 245424 (2012)].
Atomic-scale disorder induce the scattering of charge carriers between the
valleys and restores the spectral fluctuations of GOE. A simplified description
of such a nonstandard GUE-GOE transition, employing the mixed ensemble of 4x4
real symmetric matrices was also proposed. Here we complement our previous
study by analyzing numerically the spectral fluctuations of large matrices
belonging the same mixed ensemble. Resulting scaling laws relate the ensemble
parameter to physical size and the number of atomic-scale defects in graphene
flake. A phase diagram, indicating the regions in which the signatures of GUE
may by observable in the size-doping parameter plane, is presented.


title: Photo-induced gap closure in an excitonic insulator

abstract:
  We study the dynamical phase transition out of an excitonic insulator phase
after photo-excitation using a time-dependent extension of the selfconsistent
GW method. We connect the evolution of the photoemission spectra to the
dynamics of the excitonic order parameter and identify two dynamical phase
transition points marked by a slowdown in the relaxation: one critical point is
connected with the trapping in a nonthermal state with reduced exciton density
and the second corresponds to the thermal phase transition. The transfer of
kinetic energy from the photoexcited carriers to the exciton condensate is
shown to be the main mechanism for the gap melting. We analyze the low energy
dynamics of screening, which strongly depends on the presence of the excitonic
gap, and argue that it is difficult to interpret the static component of the
screened interaction as the effective interaction of some low energy model.
Instead we propose a phenomenological measure for the effective interaction
which indicates that screening has minor effects on the low energy dynamics.


title:
Bilinear identities for an extended B-type Kadomtsev-Petviashvili
  hierarchy

abstract:
  In this paper, we construct the bilinear identities for the wave functions of
an extended B-type Kadomtsev-Petviashvili (BKP) hierarchy, which contains two
types of (2+1)-dimensional Sawada-Kotera equation with a self-consistent source
(2d-SKwS-I and 2d-SKwS-II). By introducing an auxiliary variable corresponding
to the extended flow for the BKP hierarchy, we find the tau-function and the
bilinear identities for this extended BKP hierarchy. The bilinear identities
can generate all the Hirota's bilinear equations for the zero-curvature forms
of this extended BKP hierarchy. As examples, the Hirota's bilinear equations
for the two types of 2d-SKwS (both 2d-SKwS-I and 2d-SKwS-II) will be given
explicitly.


title: On Mach's Principle and the "Special" Theory of Relativity

abstract:
  First, we present a history of the school of thought that the Cosmic
Microwave Background Radiation acts as an ether in contemporary popular
English. Then we illustrate the properties of this ether and of a hypothetical
"test mass" using a brand new thought experiment. Finally, we recount some
post-Einstein efforts at a mathematical formulation of Mach's principle and
raise some questions about what implications it has for the locality of
rotation and for quantum gravity. This paper does not prove Einstein wrong.


title:
A $(p,q)$-Analogue of Poly-Euler Polynomials and Some Related
  Polynomials

abstract:
  In the present article, we introduce a $(p,q)$-analogue of the poly-Euler
polynomials and numbers by using the $(p,q)$-polylogarithm function. These new
sequences are generalizations of the poly-Euler numbers and polynomials. We
give several combinatorial identities and properties of these new polynomials.
Moreover, we show some relations with the $(p,q)$-poly-Bernoulli polynomials
and $(p,q)$-poly-Cauchy polynomials. The $(p,q)$-analogues generalize the
well-known concept of the $q$-analogue.


title: Torsion, torsion length and finitely presented groups

abstract:
  We show that a construction by Aanderaa and Cohen used in their proof of the
Higman Embedding Theorem preserves torsion length. We give a new construction
showing that every finitely presented group is the quotient of some $C'(1/6)$
finitely presented group by the subgroup generated by its torsion elements. We
use these results to show there is a finitely presented group with infinite
torsion length which is $C'(1/6)$, and thus word-hyperbolic and virtually
torsion-free.


title: Submillimeter H$_2$O megamasers in NGC 4945 and the Circinus galaxy

abstract:
  We present 321 GHz observations of five AGN from ALMA Cycle 0 archival data:
NGC 5793, NGC 1068, NGC 1386, NGC 4945, and the Circinus galaxy. Submillimeter
maser emission is detected for the first time towards NGC 4945, and we present
a new analysis of the submillimeter maser system in Circinus. None of the other
three galaxies show maser emission, though we have detected and imaged the
continuum from every galaxy. Both NGC 4945 and Circinus are known to host
strong ($\gtrsim 10$ Jy) 22 GHz megamaser emission, and VLBI observations have
shown that the masers reside in the innermost $\sim 1$ parsec of the galaxies.
The peak flux densities of the 321 GHz masers in both systems are substantially
weaker (by a factor of $\sim$100) than what is observed at 22 GHz, though the
corresponding isotropic luminosities are more closely matched (within a factor
of $\sim$10) between the two transitions. We compare the submillimeter spectra
presented here to the known 22 GHz spectra in both galaxies, and we argue that
while both transitions originate from the gaseous environment near the AGN, not
all sites are necessarily in common. In Circinus, the spectral structure of the
321 GHz masers indicates that they may trace the accretion disk at radii
interior to the 22 GHz masers. The continuum emission in NGC 4945 and NGC 5793
shows a spatial distribution indicative of an origin in the galactic disks
(likely thermal dust emission), while for the other three galaxies the emission
is centrally concentrated and likely originates from the nucleus.


title: Extrasolar comets : the origin of dust in exozodiacal disks?

abstract:
  Comets have been invoked in numerous studies as a potentially important
source of dust and gas around stars, but none has studied the thermo-physical
evolution, out-gassing rate, and dust ejection of these objects in such stellar
systems. We investigate the thermo-physical evolution of comets in
exo-planetary systems in order to provide valuable theoretical data required to
interpret observations of gas and dust. We use a quasi 3D model of cometary
nucleus to study the thermo-physical evolution of comets evolving around a
single star from 0.1 to 50 AU, whose homogeneous luminosity varies from 0.1 to
70 solar luminosities. This paper provides mass ejection, lifetimes, and the
rate of dust and water gas mass productions for comets as a function of the
distance to the star and stellar luminosity. Results show significant physical
changes to comets at high stellar luminosities. The models are presented in
such a manner that they can be readily applied to any planetary system. By
considering the examples of the Solar System, Vega and HD 69830, we show that
dust grains released from sublimating comets have the potential to create the
observed (exo)zodiacal emission. We show that observations can be reproduced by
1 to 2 massive comets or by a large number of comets whose orbits approach
close to the star. Our conclusions depend on the stellar luminosity and the
uncertain lifetime of the dust grains. We find, as in previous studies, that
exozodiacal dust disks can only survive if replenished by a population of
typically sized comets renewed from a large and cold reservoir of cometary
bodies beyond the water ice line. These comets could reach the inner regions of
the planetary system following scattering by a (giant) planet.


title: Comment on Faizal et al EPJC 76:30

abstract:
  In a recent paper in EPJC January 2016, Faizal, Khalil and Das have proposed
time crystals with duration several orders of magnitude greater than Planck
scale. We comment on this paper and shed further light on this aspect.


title: Parasitic Numbers at Arbitrary Base

abstract:
  A natural number is called an {\lambda}-parasitic number if it is multiplied
by integer {\lambda} as the rightmost digit moves to the front. The Full set of
these numbers is known in the decimal system. Here, a formula to analytically
generate parasitic numbers in any base was derived and demonstrated for the
number systems in base t = 3, 4, 5, 8, 10 and 16. It allows to generate
parasitic numbers with given numbers of periods. The formula was derived using
the definition of parasitic numbers , not their cyclical property.


title: HordeQBF: A Modular and Massively Parallel QBF Solver

abstract:
  The recently developed massively parallel satisfiability (SAT) solver
HordeSAT was designed in a modular way to allow the integration of any
sequential CDCL-based SAT solver in its core. We integrated the QCDCL-based
quantified Boolean formula (QBF) solver DepQBF in HordeSAT to obtain a
massively parallel QBF solver---HordeQBF. In this paper we describe the details
of this integration and report on results of the experimental evaluation of
HordeQBF's performance. HordeQBF achieves superlinear average and median
speedup on the hard application instances of the 2014 QBF Gallery.


title: On existence of a triangle with prescribed bisector lengths

abstract:
  We suggest a geometric visualization of the process of constructing a
triangle with prescribed bisectors that makes the existence of such a triangle
geometrically evident.


title: Determinant density and biperiodic alternating links

abstract:
  Let L be any infinite biperiodic alternating link. We show that for any
sequence of finite links that Folner converges almost everywhere to L, their
determinant densities converge to the Mahler measure of the 2-variable
characteristic polynomial of the toroidal dimer model on an associated
biperiodic graph.


title: Reconstructing QCD ghost $f(R,T)$ models

abstract:
  We reconstruct $f(R,T)$ theory (where $R$ is the scalar curvature and $T$ is
the trace of energy-momentum tensor) in the framework of QCD ghost dark energy
models. In this study, we concentrate on particular models of $f(R,T)$ gravity
which permits the standard continuity equation in this theory. It is found that
reconstructed function can represent phantom and quintessence regimes of the
universe in the background of flat FRW universe. In addition, we explore the
stability of ghost $f(R,T)$ models.


title:
Construction of the fermionic vacuum and of fermionic operators of
  creation and annihilation in the theory of algebraic spinors

abstract:
  We introduced fermionic variables in complex modules over real Clifford
algebras of even dimension which are analog of the Witt basis. We built
primitive idempotents which are a set of equivalent Clifford vacuums. It is
shown that the modules are decomposed into direct sum of minimal left ideals
generated by these idempotents and that the fermionic variables can be
considered as more fundamental mathematical objects than spinors.


title: An Arabic report about supernova SN 1006 by Ibn Sina (Avicenna)

abstract:
  We present here an Arabic report about supernova 1006 (SN 1006) written by
the famous Persian scholar Ibn Sina (Lat. Avicenna, AD 980-1037), which was not
discussed in astronomical literature before. The short observational report
about a new star is part of Ibn Sina's book called al-Shifa', a work about
philosophy including physics, astronomy, and meteorology. We present the Arabic
text and our English translation. After a detailed discussion of the dating of
the observation, we show that the text specifies that the transient celestial
object was stationary and/or tail-less ("a star among the stars"), that it
"remained for close to three months getting fainter and fainter until it
disappeared", that it "threw out sparks", i.e. it was scintillating and very
bright, and that the color changed with time. The information content is
consistent with the other Arabic and non-Arabic reports about SN 1006. Hence,
it is quite clear that Ibn Sina refers to SN 1006 in his report, given as an
example for transient celestial objects in a discussion of Aristotle's
"Meteorology". Given the wording and the description, e.g. for the color
evolution, this report is independent from other reports known so far.


title: Extending Homotopy Type Theory with Strict Equality

abstract:
  In homotopy type theory (HoTT), all constructions are necessarily stable
under homotopy equivalence. This has shortcomings: for example, it is believed
that it is impossible to define a type of semi-simplicial types. More
generally, it is difficult and often impossible to handle towers of coherences.
To address this, we propose a 2-level theory which features both strict and
weak equality. This can essentially be represented as two type theories: an
"outer" one, containing a strict equality type former, and an "inner" one,
which is some version of HoTT. Our type theory is inspired by Voevosky's
suggestion of a homotopy type system (HTS) which currently refers to a range of
ideas. A core insight of our proposal is that we no not need any form of
equality reflection in order to achieve what HTS was suggested for. Instead,
having unique identity proofs in the outer type theory is sufficient, and it
also has the meta-theoretical advantage of not breaking decidability of type
checking. The inner theory can be an easily justifiable extensions of HoTT,
allowing the construction of "infinite structures" which are considered
impossible in plain HoTT. Alternatively, we can set the inner theory to be
exactly the current standard formulation of HoTT, in which case our system can
be thought of as a type-theoretic framework for working with "schematic"
definitions in HoTT. As demonstrations, we define semi-simplicial types and
formalise constructions of Reedy fibrant diagrams.


title:
Tracking of Lines in Spherical Images via Sub-Riemannian Geodesics on
  SO(3)

abstract:
  In order to detect salient lines in spherical images, we consider the problem
of minimizing the functional $\int \limits_0^l C(\gamma(s)) \sqrt{\xi^2 +
k_g^2(s)} \, {\rm d}s$ for a curve $\gamma$ on a sphere with fixed boundary
points and directions. The total length $l$ is free, $s$ denotes the spherical
arclength, and $k_g$ denotes the geodesic curvature of $\gamma$. Here the
smooth external cost $C\geq \delta>0$ is obtained from spherical data. We lift
this problem to the sub-Riemannian (SR) problem in Lie group $SO(3)$ and show
that the spherical projection of certain SR geodesics provides a solution to
our curve optimization problem. In fact, this holds only for the geodesics
whose spherical projection does not exhibit a cusp. The problem is a spherical
extension of a well-known contour perception model, where we extend the model
by Boscain and Rossi to the general case $\xi > 0$, $C \neq 1$. For $C=1$, we
derive SR geodesics and evaluate the first cusp time. We show that these curves
have a simpler expression when they are parameterized by spherical arclength
rather than by sub-Riemannian arclength. For case $C \neq 1$ (data-driven SR
geodesics), we solve via a SR Fast Marching method. Finally, we show an
experiment of vessel tracking in a spherical image of the retina and study the
effect of including the spherical geometry in analysis of vessels curvature.


title:
Morphology and kinematics of the gas envelope of protostar L1527 as
  obtained from ALMA observations of the C$^{18}$O(2-1) line emission

abstract:
  Using ALMA observations of the C$^{18}$O(2-1) line emission of the gas
envelope of protostar L1527, we have reconstructed its morphology and
kinematics under the assumption of axisymmetry about the west-east axis. The
main original contribution to our understanding of the formation process of
L1527 is the presentation of a simple 3D parameterisation based solely on
regions that are not dominated by absorption. In the explored range ($\sim$0.7
to 5 arcsec from the star) the model reproduces observations better than
earlier attempts. The main results include: a measurement of the rotation
velocity that confirms its evolution to Keplerian toward short distances; a
measurement of the mean in-fall velocity, 0.43$\pm$0.10 kms$^{-1}$, lower than
free fall velocity, with no evidence for the significant $r$-dependence
suggested by an earlier analysis; a measurement of the central mass,
0.23$\pm$0.06 M$_{\odot}$ within a distance of 1.5 arcsec from the star, in
agreement with earlier estimates obtained from a different range of distances;
evidence for a strong disc plane depression of the in-falling flux resulting in
an $X$ shaped flow possibly caused by the freeze-out of CO molecules on dust
grains; a measurement of the accretion rate, 3.5$\pm$1.0 10$^{-7}$
M$_{\odot}$yr$^{-1}$ at a distance of 1 arcsec (140 au) from the star; evidence
for a 10$^\circ$ tilt of the symmetry plane of the envelope about the line of
sight, cancelling below $\sim$3 arcsec from the star, but matching infrared
observations and being also apparent on the sky map of the mean Doppler
velocity.


title:
Robust designs to model uncertainty with high estimation and prediction
  efficiency

abstract:
  Alphabetic optimality criteria, such as the $D$, $A$, and $I$ criteria,
require specifying a model to select optimal designs. They are not model free
and the optimal designs selected by them are not robust to model uncertainty.
Recently, many extensions of the $D$ and $A$ criteria have been proposed for
selecting robust designs with high estimation efficiency. However, approaches
for finding robust designs with high prediction efficiency are rarely studied
in the literature. In this paper, we propose the $P_\alpha$ criterion and
develop its approximation version for two-level designs, called the ${\tilde
P_\alpha}$ criterion. They are useful for selecting robust designs with high
estimation, high prediction, or balanced estimation and prediction efficiency
for projective submodels. Computational studies show that the ${\tilde
P}_\alpha$ criterion is a good approximation of the $P_\alpha$ criterion and
can reduce great computation time when we search designs over a wide range of
models. The connection between the ${\tilde P_\alpha}$ criterion and the
generalized minimum aberration (GMA) criterion is studied. Result shows that
${\tilde P_\alpha}$ plays a great role to link the alphabetic optimality
criteria and the aberration-based criteria.


title:
Sensitivity Kernels for Flows in Time-Distance Helioseismology:
  Extension to Spherical Geometry

abstract:
  We extend an existing Born approximation method for calculating the linear
sensitivity of helioseismic travel times to flows from Cartesian to spherical
geometry. This development is necessary for using the Born approximation for
inferring large-scale flows in the deep solar interior. In a first sanity
check, we compare two $f-$mode kernels from our spherical method and from an
existing Cartesian method. The horizontal and total integrals agree to within
0.3 %. As a second consistency test, we consider a uniformly rotating Sun and a
travel distance of 42 degrees. The analytical travel-time difference agrees
with the forward-modelled travel-time difference to within 2 %. In addition, we
evaluate the impact of different choices of filter functions on the kernels for
a meridional travel distance of 42 degrees. For all filters, the sensitivity is
found to be distributed over a large fraction of the convection zone. We show
that the kernels depend on the filter function employed in the data analysis
process. If modes of higher harmonic degree ($90\lesssim l \lesssim 170$) are
permitted, a noisy pattern of a spatial scale corresponding to $l\approx 260$
appears near the surface. When mainly low-degree modes are used
($l\lesssim70$), the sensitivity is concentrated in the deepest regions and it
visually resembles a ray-path-like structure. Among the different low-degree
filters used, we find the kernel for phase-speed filtered measurements to be
best localized in depth.


title: Friedmann-Robertson-Walker Models with Late-Time Acceleration

abstract:
  In order to account for the observed cosmic acceleration, a modification of
the ansatz for the variation of density in Friedman-Robertson-Walker (FRW)
models given by Islam is proposed. The modified ansatz leads to an equation of
state which corresponds to that of a variable Chaplygin gas, which in the
course of evolution reduces to that of a modified generalized Chaplygin gas
(MGCG) and a Chaplygin gas (CG), exhibiting late-time acceleration.


title: 3D Image Reconstruction from Compton camera data

abstract:
  In this paper, we address analytically and numerically the inversion of the
integral transform (\emph{cone} or \emph{Compton} transform) that maps a
function on $\mathbb{R}^3$ to its integrals over conical surfaces. It arises in
a variety of imaging techniques, e.g. in astronomy, optical imaging, and
homeland security imaging, especially when the so called Compton cameras are
involved.
  Several inversion formulas are developed and implemented numerically in $3D$
(the much simpler $2D$ case was considered in a previous publication). An
admissibility condition on detectors geometry is formulated, under which all
these inversion techniques will work.


title:
Local Optimality of Almost Piecewise-Linear Quantizers for
  Witsenhausen's Problem

abstract:
  We pose Witsenhausen's problem as a leader-follower game of incomplete
information. The follower makes a noisy observation of the leader's action (who
moves first) and chooses an action minimizing her expected deviation from the
leader's action. Knowing this, leader who observes the realization of the
state, chooses an action that minimizes her distance to the state of the world
and the ex-ante expected deviation from the follower's action. We study the
perfect Bayesian equilibria of the game and identify a class of "near
piecewise-linear equilibria" when leader cares much more about being close to
the follower than the state, and the state is highly volatile. As a major
consequence of this result, we prove the existence of a set of local minima for
Witsenhausen's problem in form of slopey quantizers, which are at most a
constant factor away from the optimal cost.


title: Fractional kinetic hierarchies and intermittency

abstract:
  We consider general convolutional derivatives and related fractional
statistical dynamics of continuous interacting particle systems. We apply the
subordination principle to construct kinetic fractional statistical dynamics in
the continuum in terms of solutions to Vlasov-type hierarchies. Conditions for
the intermittency property of fractional kinetic dynamics are obtained.


title: Pythagoras' theorem via equilateral triangles

abstract:
  We give a proof of Pythagoras' theorem which does not use neither squares nor
similarity of triangles.


title: Shadow of rotating regular black holes

abstract:
  We study the shadows cast by the different types of rotating regular black
holes viz. Ay\'on-Beato-Garc\'ia {(ABG)}, Hayward, and Bardeen. These black
holes have in addition to the total mass ($M$) and rotation parameter ($a$),
different parameters as electric charge ($Q$), deviation parameter ($g$), and
magnetic charge ($g_{*}$), respectively. Interestingly, the size of the shadow
is affected by these parameters in addition to the rotation parameter. We found
that the radius of the shadow in each case decreases monotonically and the
distortion parameter increases when the value of these parameters increase. A
comparison with the standard Kerr case is also investigated. We have also
studied the influence of the plasma environment around regular black holes to
discuss its shadow. The presence of the plasma affects the apparent size of the
regular black hole's shadow to be increased due to two effects (i)
gravitational redshift of the photons and (ii) radial dependence of plasma
density.


title:
Limits on the validity of the thin-layer model of the ionosphere for
  radio interferometric calibration

abstract:
  For a ground-based radio interferometer observing at low frequencies, the
ionosphere causes propagation delays and refraction of cosmic radio waves which
result in phase errors in the received signal. These phase errors can be
corrected using a calibration method that assumes a two-dimensional phase
screen at a fixed altitude above the surface of the Earth, known as the
thin-layer model. Here we investigate the validity of the thin-layer model and
provide a simple equation with which users can check when this approximation
can be applied to observations for varying time of day, zenith angle,
interferometer latitude, baseline length, ionospheric electron content and
observing frequency.


title:
Microstructural modeling of ductile fracture initiation in multi-phase
  materials

abstract:
  The precise mechanisms underlying the failure of multi-phase materials may be
strongly dependent on the material's microstructural morphology.
Micromechanical modeling has provided much insight into this dependence, but
uncertainties remain about crucial modeling assumptions. This paper assesses
the influence of different grain shapes, damage indicators, and stress states
using a structured numerical model. A distinct spatial arrangement of phases
around fracture incidents is found, consisting of hard regions in the tensile
direction interrupted by soft regions in the directions of shear. These key
features are only mildly sensitive to the studied variations.


title:
Search for the Standard Model Higgs boson decaying into $b\bar{b}$
  produced in association with top quarks decaying hadronically in $pp$
  collisions at $\sqrt{s}$=8 TeV with the ATLAS detector

abstract:
  A search for Higgs boson production in association with a pair of top quarks
($t\bar{t}H$) is performed, where the Higgs boson decays to $b\bar{b}$, and
both top quarks decay hadronically. The data used correspond to an integrated
luminosity of 20.3 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=8$ TeV collected
with the ATLAS detector at the Large Hadron Collider. The search selects events
with at least six energetic jets and uses a boosted decision tree algorithm to
discriminate between signal and Standard Model background. The dominant
multijet background is estimated using a dedicated data-driven technique. For a
Higgs boson mass of 125 GeV, an upper limit of 6.4 (5.4) times the Standard
Model cross section is observed (expected) at 95% confidence level. The
best-fit value for the signal strength is $\mu = 1.6 \pm 2.6$ times the
Standard Model expectation for $m_{H} = 125$ GeV. Combining all $t\bar{t}H$
searches carried out by ATLAS at $\sqrt{s}=8$ and 7 TeV, an observed (expected)
upper limit of 3.1 (1.4) times the Standard Model expectation is obtained at
95% confidence level, with a signal strength $\mu = 1.7 \pm 0.8$.


title: Non-null Slant Ruled Surfaces

abstract:
  In this study, we define some new types of non-null ruled surfaces called
slant ruled surfaces in the Minkowski 3-space E_1^3. We introduce some
characterizations for a non-null ruled surface to be a slant ruled surface in
E_1^3. Moreover, we obtain some corollaries which give the relationships
between a non-null slant ruled surface and its striction line in E_1^3.


title:
Systematic and objective identification of the microstructure around
  damage directly from images

abstract:
  An original experimental approach is presented to automatically determine the
average phase distribution around damage sites in multi-phase materials. An
objective measure is found to be the average intensity around damage sites,
calculated using many images. This method has the following benefits: no phase
identification or manual interventions are required, and statistical
fluctuations and measurement noise are effectively averaged. The method is
demonstrated for dual-phase steel, revealing subtle unexpected differences in
the morphology surrounding damage in strongly and weakly banded
microstructures.


title:
Necessary and sufficient condition for steerability of two-qubit states
  by the geometry of steering outcomes

abstract:
  Fully characterizing the steerability of a quantum state of a bipartite
system has remained an open problem since the concept of steerability was
defined. In this work, using our recent geometrical approach to steerability,
we suggest a necessary and sufficient condition for a two-qubit state to be
steerable with respect to projective measurements. To this end, we define the
critical radius of local models and show that a state of two qubits is
steerable with respect to projective measurements from Alice's side if and only
if her critical radius of local models is less than $1$. As an example, we
calculate the critical radius of local models for the so-called T-states by
proving the optimality of a recently-suggested ansatz for Alice's local hidden
state model.


title: Fractional statistical dynamics and fractional kinetics

abstract:
  We apply the subordination principle to construct kinetic fractional
statistical dynamics in the continuum in terms of solutions to Vlasov-type
hierarchies. As a by-product we obtain the evolution of the density of
particles in the fractional kinetics in terms of a non-linear Vlasov-type
kinetic equation. As an application we study the intermittency of the
fractional mesoscopic dynamics.


title:
Fracture initiation in multi-phase materials: a systematic
  three-dimensional approach using a FFT-based solver

abstract:
  This paper studies a two-phase material with a microstructure composed of a
hard brittle reinforcement phase embedded in a soft ductile matrix. It
addresses the full three-dimensional nature of the microstructure and
macroscopic deformation. A large ensemble of periodic microstructures is used,
whereby the individual grains of the two phases are modeled using equi-sized
cubes. A particular solution strategy relying on the Fast Fourier Transform is
adopted, which has a high computational efficiency both in terms of speed and
memory footprint, thus enabling a statistically meaningful analysis. This
solution method naturally accompanies the regular microstructural model, as the
Fast Fourier Transform relies on a regular grid.
  Using the many considered microstructures as an ensemble, the average
arrangement of phases around fracture initiation sites is objectively
identified by the correlation between microstructure and fracture initiation --
in three dimensions. The results show that fracture initiates where regions of
the hard phase are interrupted by bands of the soft phase that are aligned with
the direction of maximum shear. In such regions, the hard phase is arranged
such that the area of the phase boundary perpendicular to the principal strain
direction is maximum, leading to high hydrostatic tensile stresses, while not
interrupting the shear bands that form in the soft phase. The local
incompatibility that is present around the shear bands is responsible for a
high plastic strain. By comparing the response to a two-dimensional
microstructure it is observed that the response is qualitatively similar (both
macroscopically and microscopically). One important difference is that the
local strain partitioning between the two phases is over-predicted by the
two-dimensional microstructure, leading to an overestimation of damage.


title:
Long Term Effects of Small Random Perturbations on Dynamical Systems:
  Theoretical and Computational Tools

abstract:
  Small random perturbations may have a dramatic impact on the long time
evolution of dynamical systems, and large deviation theory is often the right
theoretical framework to understand these effects. At the core of the theory
lies the minimization of an action functional, which in many cases of interest
has to be computed by numerical means. Here we review the theoretical and
computational aspects behind these calculations, and propose an algorithm that
simplifies the geometric minimum action method to minimize the action in the
space of arc-length parametrized curves. We then illustrate this algorithm's
capabilities by applying it to various examples from material sciences, fluid
dynamics, atmosphere/ocean sciences, and reaction kinetics. In terms of models,
these examples involve stochastic (ordinary or partial) differential equations
with multiplicative or degenerate noise, Markov jump processes, and systems
with fast and slow degrees of freedom, which all violate detailed balance, so
that simpler computational methods are not applicable.


title:
Recent results and perspectives on cosmology and fundamental physics
  from microwave surveys

abstract:
  Recent cosmic microwave background data in temperature and polarization have
reached high precision in estimating all the parameters that describe the
current so-called standard cosmological model. Recent results about the
integrated Sachs-Wolfe effect from cosmic microwave background anisotropies,
galaxy surveys, and their cross-correlations are presented. Looking at fine
signatures in the cosmic microwave background, such as the lack of power at low
multipoles, the primordial power spectrum and the bounds on non-Gaussianities,
complemented by galaxy surveys, we discuss inflationary physics and the
generation of primordial perturbations in the early Universe. Three important
topics in particle physics, the bounds on neutrinos masses and parameters, on
thermal axion mass and on the neutron lifetime derived from cosmological data
are reviewed, with attention to the comparison with laboratory experiment
results. Recent results from cosmic polarization rotation analyses aimed at
testing the Einstein equivalence principle are presented. Finally, we discuss
the perspectives of next radio facilities for the improvement of the analysis
of future cosmic microwave background spectral distortion experiments.


title:
Quantum Levy flights and multifractality of dipolar excitations in a
  random system

abstract:
  We consider dipolar excitations propagating via dipole-induced exchange among
immobile molecules randomly spaced in a lattice. The character of the
propagation is determined by long-range hops (Levy flights). We analyze the
eigen-energy spectra and the multifractal structure of the wavefunctions. In 1D
and 2D all states are localized, although in 2D the localization length can be
extremely large leading to an effective localization-delocalization crossover
in realistic systems. In 3D all eigenstates are extended but not always
ergodic, and we identify the energy intervals of ergodic and non-ergodic
states. The reduction of the lattice filling induces an ergodic to non-ergodic
transition, and the excitations are mostly non-ergodic at low filling.


title:
The Effect of Multi-core Communication Architecture on System
  Performance

abstract:
  MPSoCs are gaining popularity because of its potential to solve
computationally expensive applications. A multi-core processor combines two or
more independent cores (normally a CPU) into a single package composed of a
single integrated circuit (Chip). However, as the number of components on a
single chip and their performance continue to increase, a shift from
computation-based to communication-based design becomes mandatory. As a result,
the communication architecture plays a major role in the area, performance, and
energy consumption of the overall system. In this paper, multiple soft-cores
(IPs) such as Micro Blaze in an FPGA is used to study the effect of different
connection topologies on the performance of a parallel program.


title:
The role of ionized impurity scattering on the thermoelectric
  performances of rock salt AgPbmSnSe2+m

abstract:
  We report on the successful synthesis and on the properties of
polycrystalline AgPbmSnSe2+m (m = ++++, 100, 50, 25) samples with a rock salt
structure. Between 160 K and 400 K, the dominant scattering process of the
carriers in this system changes from acoustic phonon scattering in PbSe to
ionized impurity scattering in AgPbmSnSe2+m, which synergistically optimizes
electrical and thermal transport properties. Thanks to the faint amount of
AgSnSe2, the Seebeck coefficient is enhanced by boosting the scattering factor,
the electric conductivity is improved by the increase of the concentration of
holes coupled to a limited degradation of their mobility, and the total thermal
conductivity is reduced by suppressing bipolar thermal conductivity. Therefore,
ZT of AgPbmSnSe2+m (m = 50) reaches 1.3 at 889 K. The mechanism suggested in
this study opens new paths to improve the thermoelectric performances of other
families of materials.


title: Analysis of a trunk reservation policy in the framework of fog computing

abstract:
  We analyze in this paper a system composed of two data centers with limited
capacity in terms of servers. When one request for a single server is blocked
at the first data center, this request is forwarded to the second one. To
protect the single server requests originally assigned to the second data
center, a trunk reservation policy is introduced (i.e., a redirected request is
accepted only if there is a sufficient number of free servers at the second
data center). After rescaling the system by assuming that there are many
servers in both data centers and high request arrival rates, we are led to
analyze a random walk in the quarter plane, which has the particularity of
having non constant reflecting conditions on one boundary of the quarter plane.
Contrary to usual reflected random walks, to compute the stationary
distribution of the presented random walk, we have to determine three unknown
functions, one polynomial and two infinite generating functions. We show that
the coefficients of the polynomial are solutions to a linear system. After
solving this linear system, we are able to compute the two other unknown
functions and the blocking probabilities at both data centers. Numerical
experiments are eventually performed to estimate the gain achieved by the trunk
reservation policy.


title:
Information-theoretically Secure Key Agreement over Partially Corrupted
  Channels

abstract:
  Key agreement is a fundamental cryptographic primitive. It has been proved
that key agreement protocols with security against computationally unbounded
adversaries cannot exist in a setting where Alice and Bob do not have dependent
variables and communication between them is fully public, or fully controlled
by the adversary. In this paper we consider this problem when the adversary can
"partially" control the channel. We motivate these adversaries by considering
adversarial corruptions at the physical layer of communication, give a
definition of adversaries that can "partially" eavesdrop and "partially"
corrupt the communication. We formalize security and reliability of key
agreement protocols, derive bounds on the rate of key agreement, and give
constructions that achieve the bound. Our results show that it is possible to
have secret key agreement as long as some of the communicated symbols remain
private and unchanged by the adversary. We relate our results to the previous
known results, and discuss future work.


title: Symmetrization and anti-symmetrization in parabolic equations

abstract:
  We derive some symmetrization and anti-symmetrization properties of parabolic
equations. First, we deduce from a result by Jones a quantitative estimate of
how far the level sets of solutions are from being spherical. Next, using this
property, we derive a criterion providing solutions whose level sets do not
converge to spheres for a class of equations including linear equations and
Fisher-KPP reaction-diffusion equations.


title:
Invariance Principle for the one-dimensional dynamic Random Conductance
  Model under Moment Conditions

abstract:
  Recent progress in the understanding of quenched invariance principles (QIP)
for a continuous-time random walk on $\mathbb{Z}^d$ in an environment of
dynamical random conductances is reviewed and extended to the $1$-dimensional
case. The law of the conductances is assumed to be ergodic with respect to
time-space shifts and satisfies certain integrability conditions.