title:
Characterising molecules for fundamental physics: an accurate
  spectroscopic model of methyltrioxorhenium derived from new infrared and
  millimetre-wave measurements

abstract:
  Precise spectroscopic analysis of polyatomic molecules enables many striking
advances in physical chemistry and fundamental physics. We use several new
high-resolution spectroscopic devices to improve our understanding of the
rotational and rovibrational structure of methyltrioxorhenium (MTO), the
achiral parent of a family of large oxorhenium compounds that are ideal
candidate species for a planned measurement of parity violation in chiral
molecules. Using millimetre-wave and infrared spectroscopy in a pulsed
supersonic jet, a cryogenic buffer gas cell, and room temperature absorption
cells, we probe the ground state and the Re=O antisymmetric and symmetric
stretching excited states of both CH3 187 ReO3 and CH3 185 ReO3 isotopologues
in the gas phase with unprecedented precision. By extending the rotational
spectra to the 150-300 GHz range, we characterize the ground state rotational
and hyperfine structure up to J = 43 and K = 41, resulting in refinements to
the rotational, quartic and hyperfine parameters, and the determination of
sextic parameters and a centrifugal distortion correction to the quadrupolar
hyperfine constant. We obtain rovibrational data for temperatures between 6 and
300 K in the 970-1015 cm-1 range, at resolutions down to 8 MHz and accuracies
of 30 MHz. We use these data to determine more precise excited-state
rotational, Coriolis and quartic parameters, as well as the ground-state
centrifugal distortion parameter D K of the 187 Re isotopologue. We also
account for hyperfine structure in the rovibrational transitions and hence
determine the upper state rhenium atom quadrupole coupling constant eQq' .


title: The [Ne III] Jet of DG Tau and its Ionization Scenarios

abstract:
  Forbidden neon emission from jets of low-mass young stars can be used to
probe the underlying high-energy processes in these systems. We analyze spectra
of the jet of DG Tau obtained with the Very Large Telescope/X-Shooter
spectrograph in 2010. [Ne III] $\lambda$3869 is clearly detected in the
innermost 3" microjet and the outer knot located at $\sim$6".5. The velocity
structure of the inner microjet can be decomposed into the low-velocity
component (LVC) at $\sim -70$ km/s and the high-velocity component (HVC) at
$\sim -180$ km/s. Based on the observed [Ne III] flux and its spatial extent,
we suggest the origins of the [Ne III] emission regions and their relation with
known X-ray sources along the jet. The flares from the hard X-ray source close
to the star may be the main ionization source of the innermost microjet. The
fainter soft X-ray source at 0".2 from the star may provide sufficient heating
to help to sustain the ionization fraction against the recombination in the
flow. The outer knot may be reionized by shocks faster than 100 km/s such that
[Ne III] emission reappears and that the soft X-ray emission at 5".5 is
produced. Velocity decomposition of the archival Hubble Space Telescope spectra
obtained in 1999 shows that the HVC had been faster, with a velocity centroid
of $\sim -260$ km/s. Such a decrease in velocity may potentially be explained
by the expansion of the stellar magnetosphere, changing the truncation radius
and thus the launching speed of the jet. The energy released by magnetic
reconnections during relaxation of the transition can heat the gas up to
several tens of megakelvin and provide the explanation for on-source keV X-ray
flares that ionize the neon microjet.


title:
Three-phonon and four-phonon interaction processes in a pair-condensed
  Fermi gas

abstract:
  We study the interactions among phonons and the phonon lifetime in a
pair-condensed Fermi gas in the BEC-BCS crossover in the collisionless regime.
To compute the phonon-phonon coupling amplitudes we use a microscopic model
based on a generalized BCS Ansatz including moving pairs, which allows for a
systematic expansion around the mean field BCS approximation of the ground
state. We show that the quantum hydrodynamic expression of the amplitudes
obtained by Landau and Khalatnikov apply only on the energy shell, that is for
resonant processes that conserve energy. The microscopic model yields the same
excitation spectrum as the Random Phase Approximation, with a linear (phononic)
start and a concavity at low wave number that changes from upwards to downwards
in the BEC-BCS crossover. When the concavity of the dispersion relation is
upwards at low wave number, the leading damping mechanism at low temperature is
the Beliaev-Landau process 2 phonons $\leftrightarrow$ 1 phonon while, when the
concavity is downwards, it is the Landau-Khalatnikov process 2 phonons
$\leftrightarrow$ 2 phonons. In both cases, by rescaling the wave vectors to
absorb the dependence on the interaction strength, we obtain a universal
formula for the damping rate. This universal formula corrects and extends the
original analytic results of Landau and Khalatnikov [ZhETF {\bf 19}, 637
(1949)] for the $2\leftrightarrow2$ processes in the downward concavity case.
In the upward concavity case, for the Beliaev 1$\leftrightarrow$ 2 process for
the unitary gas at zero temperature, we calculate the damping rate of an
excitation with wave number $q$ including the first correction proportional to
$q^7$ to the $q^5$ hydrodynamic prediction, which was never done before in a
systematic way.


title: CM relations in fibered powers of elliptic families

abstract:
  Let $E_\lambda$ be the Legendre family of elliptic curves. Given $n$ linearly
independent points $P_1,\dots , P_n \in
E_\lambda\left(\overline{\mathbb{Q}(\lambda)}\right)$ we prove that there are
at most finitely many complex numbers $\lambda_0$ such that $E_{\lambda_0} $
has complex multiplication and $P_1(\lambda_0), \dots ,P_n(\lambda_0)$ are
dependent over $End(E_{\lambda_0})$. This implies a positive answer to a
question of Bertrand and, combined with a previous work in collaboration with
Capuano, proves the Zilber-Pink conjecture for a curve in a fibered power of an
elliptic scheme when everything is defined over $\overline{\mathbb{Q}}$.


title:
Role of the ratio of biopolyelectrolyte persistence length to
  nanoparticle size in the structural tuning of electrostatic complexes

abstract:
  Aggregation of nanoparticles of given size $R$ induced by addition of a
polymer strongly depends on its degree of rigidity. This is shown here on a
large variety of silica nanoparticle self-assemblies obtained by electrostatic
complexation with carefully selected oppositely charged bio-polyelectrolytes of
different rigidity. The effective rigidity is quantified by the total
persistence length $L_T$ representing the sum of the intrinsic ($L_p$) and
electrostatic ($L_e$) polyelectrolyte persistence length, which depends on the
screening, i.e., on ionic strength due to counter-ions and external salt
concentrations. We experimentally show for the first time that the ratio L T /R
is the main tuning parameter that controls the fractal dimension D f of the
nanoparticles self-assemblies, which is determined using small-angle neutron
scattering: (i) For $L_T /R<0.3$ (obtained with flexible poly-L-lysine in the
presence of an excess of salt), chain flexibility promotes easy wrapping around
nanoparticles in excess hence ramified structures with $D_f \sim 2$. (ii) For
$0.3<L_T /R\le1$ (semiflexible chitosan or hyaluronan complexes), chain
stiffness promotes the formation of one-dimensional nanorods (in excess of
nanoparticles), in good agreement with computer simulations. (iii) For $L_T
/R>1$, $L_e$ is strongly increased due to the absence of salt and repulsions
between nanoparticles cannot be compensated by the polyelectrolyte wrapping,
which allow a spacing between nanoparticles and the formation of one
dimensional pearl necklace complexes. (iv) Finally, electrostatic 2 screening,
i.e. ionic strength, turned out to be a reliable way of controlling $D_f$ and
the phase diagram behavior. It finely tunes the short-range interparticle
potential, resulting in larger fractal dimensions at higher ionic strength.


title: Linear Convergence of SVRG in Statistical Estimation

abstract:
  SVRG and its variants are among the state of art optimization algorithms for
large scale machine learning problems. It is well known that SVRG converges
linearly when the objective function is strongly convex. However this setup can
be restrictive, and does not include several important formulations such as
Lasso, group Lasso, logistic regression, and some non-convex models including
corrected Lasso and SCAD. In this paper, we prove that, for a class of
statistical M-estimators covering examples mentioned above, SVRG solves the
formulation with {\em a linear convergence rate} without strong convexity or
even convexity. Our analysis makes use of {\em restricted strong convexity},
under which we show that SVRG converges linearly to the fundamental statistical
precision of the model, i.e., the difference between true unknown parameter
$\theta^*$ and the optimal solution $\hat{\theta}$ of the model.


title: Optimal shrinkage-based portfolio selection in high dimensions

abstract:
  In this paper we estimate the mean-variance portfolio in the high-dimensional
case using the recent results from the theory of random matrices. We construct
a linear shrinkage estimator which is distribution-free and is optimal in the
sense of maximizing with probability $1$ the asymptotic out-of-sample expected
utility, i.e., mean-variance objective function for different values of risk
aversion coefficient which in particular leads to the maximization of the
out-of-sample expected utility and to the minimization of the out-of-sample
variance.
  One of the main features of our estimator is the inclusion of the estimation
risk related to the sample mean vector into the high-dimensional portfolio
optimization. The asymptotic properties of the new estimator are investigated
when the number of assets $p$ and the sample size $n$ tend simultaneously to
infinity such that $p/n \rightarrow c\in (0,+\infty)$. The results are obtained
under weak assumptions imposed on the distribution of the asset returns, namely
the existence of the $4+\varepsilon$ moments is only required.
  Thereafter we perform numerical and empirical studies where the small- and
large-sample behavior of the derived estimator is investigated. The suggested
estimator shows significant improvements over the existent approaches including
the nonlinear shrinkage estimator and the three-fund portfolio rule, especially
when the portfolio dimension is larger than the sample size. Moreover, it is
robust to deviations from normality.


title:
An introduction to quantum discord and non-classical correlations beyond
  entanglement

abstract:
  In this didactic article we explore the concept of quantum correlations
beyond entanglement. We begin by introducing and motivating the classically
correlated states and then showing how to quantify the quantum correlations
using an entropic approach, arriving at a well known measure called the quantum
discord. Quantum correlations and discord are then operationally linked with
the task of local broadcasting. We conclude by providing some alternative
perspectives on quantum correlations and how to measure them.

categories: quant-ph cond-mat.stat-mech math-ph math.MP physics.data-an


title: A New Error Correction Scheme for Physical Unclonable Functions

abstract:
  Error correction is an indispensable component when Physical Unclonable
Functions (PUFs) are used in cryptographic applications. So far, there exist
schemes that obtain helper data, which they need within the error correction
process. We introduce a new scheme, which only uses an error correcting code
without any further helper data. The main idea is to construct for each PUF
instance an individual code which contains the initial PUF response as
codeword. In this work we use LDPC codes, however other code classes are also
possible. Our scheme allows a trade-off between code rate and cryptographic
security. In addition, decoding with linear complexity is possible.


title:
Unique probe of dark matter in the core of M87 with the Event Horizon
  Telescope

abstract:
  We demonstrate the unprecedented capabilities of the Event Horizon Telescope
(EHT) to image the innermost dark matter profile in the vicinity of the
supermassive black hole at the center of the M87 radio galaxy. We present the
first model of the synchrotron emission induced by dark matter annihilations
from a spiky profile in the close vicinity of a supermassive black hole,
accounting for strong gravitational lensing effects. Our results show that the
EHT should readily resolve dark matter spikes if present. Moreover, the photon
ring surrounding the silhouette of the black hole is clearly visible in the
spike emission, which introduces observable small-scale structure into the
signal. We find that the dark matter-induced emission provides an adequate fit
to the existing EHT data, implying that in addition to the jet, a dark matter
spike may account for a sizable portion of the millimeter emission from the
innermost (subparsec) region of M87. Regardless, our results show that the EHT
can probe very weakly annihilating dark matter. Current EHT observations
already constrain very small cross sections, typically down to a few 10^{-31}
cm^{3} s^{-1} for a 10 GeV candidate, close to characteristic values for
p-wave-suppressed annihilation. Future EHT observations will further improve
constraints on the DM scenario.

categories: astro-ph.GA astro-ph.CO astro-ph.HE hep-ph


title: High-Resolution Semantic Labeling with Convolutional Neural Networks

abstract:
  Convolutional neural networks (CNNs) have received increasing attention over
the last few years. They were initially conceived for image categorization,
i.e., the problem of assigning a semantic label to an entire input image.
  In this paper we address the problem of dense semantic labeling, which
consists in assigning a semantic label to every pixel in an image. Since this
requires a high spatial accuracy to determine where labels are assigned,
categorization CNNs, intended to be highly robust to local deformations, are
not directly applicable.
  By adapting categorization networks, many semantic labeling CNNs have been
recently proposed. Our first contribution is an in-depth analysis of these
architectures. We establish the desired properties of an ideal semantic
labeling CNN, and assess how those methods stand with regard to these
properties. We observe that even though they provide competitive results, these
CNNs often underexploit properties of semantic labeling that could lead to more
effective and efficient architectures.
  Out of these observations, we then derive a CNN framework specifically
adapted to the semantic labeling problem. In addition to learning features at
different resolutions, it learns how to combine these features. By integrating
local and global information in an efficient and flexible manner, it
outperforms previous techniques. We evaluate the proposed framework and compare
it with state-of-the-art architectures on public benchmarks of high-resolution
aerial image labeling.


title:
Interaction between global-scale atmospheric vortices: Modeling with
  Hamiltonian dynamic system of antipodal point vortices on a rotating sphere

abstract:
  We get point vortices dynamics equations on a rotating sphere surface
directly from the hydrodynamic equations as representing their weak exact
solution contrary to the conventional case of the use of a kinematic
relationship between a given singular vortex field and velocity field. It is
first time that the effect of a sphere rotation on the vortices interaction is
accounted for in exact form. We show that only the stream function of a vortex
pair of antipodal vortices (APV), and only it satisfies the original
three-dimensional hydrodynamics equations on a sphere. We prove that only APV
pair with two point vortices in the diameter-conjugated points of a sphere with
equal by quantity but different sign circulations may be correctly considered
as an elementary (stationary, not self-affecting) singular point object on a
sphere. We suggest using the axis connecting the two point vortices in an APV
for describing of an axis of rotation of the global vortices introduced in
(Barrett, 1958) to reflect the observed global rotation of atmospheric masses
with the rotation axes not coinciding with the planet rotation axis and
precessing about it. Up to now, the question about interaction of global
vortices corresponding to such solutions with rotations about different axis
was not even posed. This is the first model describing interaction of the
Barrett-type global vortices corresponding to atmospheric centers of action
(ACA). The new steady-state and its stability conditions for N=2 are obtained
and used for the analysis of coupled cyclone-anticyclone ACAs over oceans in
the Northern Hemisphere. On the base of corresponding exact solutions, we show
acceptability of modelling of the stable blocks of splitting flow type when in
line with the exact accounting for the sphere rotation, we define also
conditions of the polar vortices affecting on the stability boundaries of the
block modes.


title: Log-time and Log-space Extreme Classification

abstract:
  We present LTLS, a technique for multiclass and multilabel prediction that
can perform training and inference in logarithmic time and space. LTLS embeds
large classification problems into simple structured prediction problems and
relies on efficient dynamic programming algorithms for inference. We train LTLS
with stochastic gradient descent on a number of multiclass and multilabel
datasets and show that despite its small memory footprint it is often
competitive with existing approaches.


title:
Relations Between Work and Entropy Production for General
  Information-Driven, Finite-State Engines

abstract:
  We consider a system model of a general finite-state machine (ratchet) that
simultaneously interacts with three kinds of reservoirs: a heat reservoir, a
work reservoir, and an information reservoir, the latter being taken to be a
running digital tape whose symbols interact sequentially with the machine. As
has been shown in earlier work, this finite-state machine can act as a demon
(with memory), which creates a net flow of energy from the heat reservoir into
the work reservoir (thus extracting useful work) at the price of increasing the
entropy of the information reservoir. Under very few assumptions, we propose a
simple derivation of a family of inequalities that relate the work extraction
with the entropy production. These inequalities can be seen as either upper
bounds on the extractable work or as lower bounds on the entropy production,
depending on the point of view. Many of these bounds are relatively easy to
calculate and they are tight in the sense that equality can be approached
arbitrarily closely. In their basic forms, these inequalities are applicable to
any finite number of cycles (and not only asymptotically), and for a general
input information sequence (possibly correlated), which is not necessarily
assumed even stationary. Several known results are obtained as special cases.


title: Having the same wild ramification is preserved by the direct image

abstract:
  We introduce the notion that two elements of Grothendieck groups of
constructible sheaves on a separated scheme over an excellent henselian
discrete valuation ring have the same wild ramification. We prove that this
condition is preserved by four of Grothendieck's six operations except the
derived tensor product and the derived hom.


title: Regularizing CNNs with Locally Constrained Decorrelations

abstract:
  Regularization is key for deep learning since it allows training more complex
models while keeping lower levels of overfitting. However, the most prevalent
regularizations do not leverage all the capacity of the models since they rely
on reducing the effective number of parameters. Feature decorrelation is an
alternative for using the full capacity of the models but the overfitting
reduction margins are too narrow given the overhead it introduces. In this
paper, we show that regularizing negatively correlated features is an obstacle
for effective decorrelation and present OrthoReg, a novel regularization
technique that locally enforces feature orthogonality. As a result, imposing
locality constraints in feature decorrelation removes interferences between
negatively correlated feature weights, allowing the regularizer to reach higher
decorrelation bounds, and reducing the overfitting more effectively. In
particular, we show that the models regularized with OrthoReg have higher
accuracy bounds even when batch normalization and dropout are present.
Moreover, since our regularization is directly performed on the weights, it is
especially suitable for fully convolutional neural networks, where the weight
space is constant compared to the feature map space. As a result, we are able
to reduce the overfitting of state-of-the-art CNNs on CIFAR-10, CIFAR-100, and
SVHN.


title:
Transit Shapes and Self Organising Maps as a Tool for Ranking Planetary
  Candidates: Application to Kepler and K2

abstract:
  A crucial step in planet hunting surveys is to select the best candidates for
follow up observations, given limited telescope resources. This is often
performed by human `eyeballing', a time consuming and statistically awkward
process. Here we present a new, fast machine learning technique to separate
true planet signals from astrophysical false positives. We use Self Organising
Maps (SOMs) to study the transit shapes of \emph{Kepler} and \emph{K2} known
and candidate planets. We find that SOMs are capable of distinguishing known
planets from known false positives with a success rate of 87.0\%, using the
transit shape alone. Furthermore, they do not require any candidates to be
dispositioned prior to use, meaning that they can be used early in a mission's
lifetime. A method for classifying candidates using a SOM is developed, and
applied to previously unclassified members of the \emph{Kepler} KOI list as
well as candidates from the \emph{K2} mission. The method is extremely fast,
taking minutes to run the entire KOI list on a typical laptop. We make
\texttt{Python} code for performing classifications publicly available, using
either new SOMs or those created in this work. The SOM technique represents a
novel method for ranking planetary candidate lists, and can be used both alone
or as part of a larger autovetting code.


title:
Finite-Horizon Throughput Region for Wireless Multi-User Interference
  Channels

abstract:
  This paper studies a wireless network consisting of multiple
transmitter-receiver pairs where interference is treated as noise. Previously,
the throughput region of such networks was characterized for either one time
slot or an infinite time horizon. We aim to fill the gap by investigating the
throughput region for transmissions over a finite time horizon. Unlike the
infinite-horizon throughput region, which is simply the convex hull of the
throughput region of one time slot, the finite-horizon throughput region is
generally non-convex. Instead of directly characterizing all achievable
rate-tuples in the finite-horizon throughput region, we propose a metric termed
the rate margin, which not only determines whether any given rate-tuple is
within the throughput region (i.e., achievable or unachievable), but also tells
the amount of scaling that can be done to the given achievable (unachievable)
rate-tuple such that the resulting rate-tuple is still within (brought back
into) the throughput region. Furthermore, we derive an efficient algorithm to
find the rate-achieving policy for any given rate-tuple in the finite-horizon
throughput region.


title:
Localization-Delocalization Transitions in Bosonic Random Matrix
  Ensembles

abstract:
  Localization to delocalization transitions in eigenfunctions are studied for
finite interacting boson systems by employing one- plus two-body embedded
Gaussian orthogonal ensemble of random matrices [EGOE(1+2)]. In the first
analysis, considered are bosonic EGOE(1+2) for two-species boson systems with a
fictitious ($F$) spin degree of freedom [called BEGOE(1+2)-$F$]. Numerical
calculations are carried out as a function of the two-body interaction strength
($\lambda$). It is shown that, in the region (defined by $\lambda>\lambda_c$)
after the onset of Poisson to GOE transition in energy levels, the strength
functions exhibit Breit-Wigner to Gaussian transition for
$\lambda>\lambda_{F_k}>\lambda_c$. Further, analyzing information entropy and
participation ratio, it is established that there is a region defined by
$\lambda\sim\lambda_t$ where the system exhibits thermalization. The $F$-spin
dependence of the transition markers $\lambda_{F_k}$ and $\lambda_t$ follow
from the propagator for the spectral variances. These results, well tested near
the center of the spectrum and extend to the region within $\pm2\sigma$ to
$\pm3\sigma$ from the center ($\sigma^2$ is the spectral variance), establish
universality of the transitions generated by embedded ensembles. In the second
analysis, entanglement entropy is studied for spin-less BEGOE(1+2) ensemble and
shown that the results generated are close to the recently reported results for
a Bose-Hubbard model.


title: One Class Splitting Criteria for Random Forests

abstract:
  Random Forests (RFs) are strong machine learning tools for classification and
regression. However, they remain supervised algorithms, and no extension of RFs
to the one-class setting has been proposed, except for techniques based on
second-class sampling. This work fills this gap by proposing a natural
methodology to extend standard splitting criteria to the one-class setting,
structurally generalizing RFs to one-class classification. An extensive
benchmark of seven state-of-the-art anomaly detection algorithms is also
presented. This empirically demonstrates the relevance of our approach.


title: Fixed-point Factorized Networks

abstract:
  In recent years, Deep Neural Networks (DNN) based methods have achieved
remarkable performance in a wide range of tasks and have been among the most
powerful and widely used techniques in computer vision. However, DNN-based
methods are both computational-intensive and resource-consuming, which hinders
the application of these methods on embedded systems like smart phones. To
alleviate this problem, we introduce a novel Fixed-point Factorized Networks
(FFN) for pretrained models to reduce the computational complexity as well as
the storage requirement of networks. The resulting networks have only weights
of -1, 0 and 1, which significantly eliminates the most resource-consuming
multiply-accumulate operations (MACs). Extensive experiments on large-scale
ImageNet classification task show the proposed FFN only requires one-thousandth
of multiply operations with comparable accuracy.


title: Lattice QCD results on cumulant ratios at freeze-out

abstract:
  Ratios of cumulants of net proton-number fluctuations measured by the STAR
Collaboration show strong deviations from a skellam distribution, which should
describe thermal properties of cumulant ratios, if proton-number fluctuations
are generated in equilibrium and a hadron resonance gas (HRG) model would
provide a suitable description of thermodynamics at the freeze-out temperature.
We present some results on sixth order cumulants entering the calculation of
the QCD equation of state at non-zero values of the baryon chemical potential
(mu_B) and discuss limitations on the applicability of HRG thermodynamics
deduced from a comparison between QCD and HRG model calculations of cumulants
of conserved charge fluctuations. We show that basic features of the
$\mu_B$-dependence of skewness and kurtosis ratios of net proton-number
fluctuations measured by the STAR Collaboration resemble those expected from a
O(mu_B^2) QCD calculation of the corresponding net baryon-number cumulant
ratios.


title: Item-to-item recommendation based on Contextual Fisher Information

abstract:
  Web recommendation services bear great importance in e-commerce, as they aid
the user in navigating through the items that are most relevant to her needs.
In a typical Web site, long history of previous activities or purchases by the
user is rarely available. Hence in most cases, recommenders propose items that
are similar to the most recent ones viewed in the current user session. The
corresponding task is called session based item-to-item recommendation. For
frequent items, it is easy to present item-to-item recommendations by "people
who viewed this, also viewed" lists. However, most of the items belong to the
long tail, where previous actions are sparsely available. Another difficulty is
the so-called cold start problem, when the item has recently appeared and had
no time yet to accumulate sufficient number of transactions. In order to
recommend a next item in a session in sparse or cold start situations, we also
have to incorporate item similarity models. In this paper we describe a
probabilistic similarity model based on Random Fields to approximate
item-to-item transition probabilities. We give a generative model for the item
interactions based on arbitrary distance measures over the items including
explicit, implicit ratings and external metadata. The model may change in time
to fit better recent events and recommend the next item based on the updated
Fisher Information. Our new model outperforms both simple similarity baseline
methods and recent item-to-item recommenders, under several different
performance metrics and publicly available data sets. We reach significant
gains in particular for recommending a new item following a rare item.


title: Witness for initial correlations among environments

abstract:
  A quantum system inevitably interacts with its surroundings. In general, one
does not have detailed information on an environment. Identifying the
environmental features can help us to control the environment and its effects
on the dynamics of an open system. Here, we consider a tripartite system and
introduce a witness for the initial correlations among environments by means of
the concept of the trace distance. Due to the existence of the initial
environmental correlations, a tight upper bound is obtained for the growth of
the trace distance of open quantum system states. Therefore, the initial
correlations among the environments subject to particular conditions can be
detected by measurements on the open system.


title:
Bounds on solutions of the rotating, stratified, incompressible,
  non-hydrostatic, three-dimensional Boussinesq equations

abstract:
  We study the three-dimensional, incompressible, non-hydrostatic Boussinesq
fluid equations, which are applicable to the dynamics of the oceans and
atmosphere. These equations describe the interplay between velocity and
buoyancy in a rotating frame. A hierarchy of dynamical variables is introduced
whose members $\Omega_{m}(t)$ ($1 \leq m < \infty$) are made up from the
respective sum of the $L^{2m}$-norms of vorticity and the density gradient.
Each $\Omega_{m}(t)$ has a lower bound in terms of the inverse Rossby number,
$Ro^{-1}$, that turns out to be crucial to the argument. For convenience, the
$\Omega_{m}$ are also scaled into a new set of variables $D_{m}(t)$. By
assuming the existence and uniqueness of solutions, conditional upper bounds
are found on the $D_{m}(t)$ in terms of $Ro^{-1}$ and the Reynolds number $Re$.
These upper bounds vary across bands in the $\{D_{1},\,D_{m}\}$ phase plane.
The boundaries of these bands depend subtly upon $Ro^{-1}$, $Re$, and the
inverse Froude number $Fr^{-1}$. For example, solutions in the lower band
conditionally live in an absorbing ball in which the maximum value of
$\Omega_{1}$ deviates from $Re^{3/4}$ as a function of $Ro^{-1},\,Re$ and
$Fr^{-1}$.


title:
Flux-limited and classical viscosity solutions for regional control
  problems

abstract:
  The aim of this paper is to compare two different approaches for regional
control problems: the first one is the classical approach, using a standard
notion of viscosity solutions, which is developed in a series of works by the
three first authors. The second one is more recent and relies on ideas
introduced by Monneau and the fourth author for problems set on networks in
another series of works, in particular the notion of flux-limited solutions.
After describing and even revisiting these two very different points of view in
the simplest possible framework, we show how the results of the classical
approach can be interpreted in terms of flux-limited solutions. In particular,
we give much simpler proofs of three results: the comparison principle in the
class of bounded flux-limited solutions of stationary multidimensional
Hamilton-Jacobi equations and the identification of the maximal and minimal
Ishii's solutions with flux-limited solutions which were already proved by
Monneau and the fourth author, and the identification of the corresponding
vanishing viscosity limit, already obtained by Vinh Duc Nguyen and the fourth
author.


title:
A Robust Multi-Scale Field-Only Formulation of Electromagnetic
  Scattering

abstract:
  We present a boundary integral formulation of electromagnetic scattering by
homogeneous bodies that are characterized by linear constitutive equations in
the frequency domain. By working with the Cartesian components of the electric,
E and magnetic, H fields and with the scalar functions (r*E) and (r*H), the
problem is cast as solving a set of scalar Helmholtz equations for the field
components that are coupled by the usual electromagnetic boundary conditions at
material boundaries. This facilitates a direct solution for E and H rather than
working with surface currents as intermediate quantities in existing methods.
Consequently, our formulation is free of the well-known numerical instability
that occurs in the zero frequency or long wavelength limit in traditional
surface integral solutions of Maxwell's equations and our numerical results
converge uniformly to the static results in the long wavelength limit.
Furthermore, we use a formulation of the scalar Helmholtz equation that is
expressed as classically convergent integrals and does not require the
evaluation of principal value integrals or any knowledge of the solid angle.
Therefore, standard quadrature and higher order surface elements can readily be
used to improve numerical precision. In addition, near and far field values can
be calculated with equal precision and multiscale problems in which the
scatterers possess characteristic length scales that are both large and small
relative to the wavelength can be easily accommodated. From this we obtain
results for the scattering and transmission of electromagnetic waves at
dielectric boundaries that are valid for any ratio of the local surface
curvature to the wave number. This is a generalization of the familiar Fresnel
formula and Snell's law, valid at planar dielectric boundaries, for the
scattering and transmission of electromagnetic waves at surfaces of arbitrary
curvature.


title:
Nuclear structure calculations in $^{20}$Ne with No-Core
  Configuration-Interaction model

abstract:
  Negative parity states in $^{20}$Ne and Gamow-Teller strength distribution
for the ground-state beta-decay of $^{20}$Na are calculated for the very first
time using recently developed No-Core Configuration-Interaction model. The
approach is based on multi-reference density functional theory involving
isospin and angular-momentum projections. Advantages and shortcomings of the
method are briefly discussed.


title:
Fluidization and wall slip of soft-glassy materials by controlled
  surface roughness

abstract:
  The motion of soft-glassy materials (SGM) in a confined geometry is strongly
impacted by surface roughness. However, the effect of the spatial distribution
of the roughness remains poorly understood from a more quantitative viewpoint.
Here we present a comprehensive study of concentrated emulsions flowing in
microfluidic channels, one wall of which is patterned with micron-size equally
spaced grooves oriented perpendicularly to the flow direction. We show that
roughness-induced fluidization can be quantitatively tailored by systematically
changing both the width and separation of the grooves. We find that a simple
scaling law describes such fluidization as a function of the density of
grooves, suggesting common scenarios for droplet trapping and release.
Numerical simulations confirm these views and are used to elucidate the
relation between fluidization and the rate of plastic rearrangements.


title:
Optical Process of Linear Dichroism in Angle-Resolved Core-Level
  Photoemission Reflecting Strongly Correlated Anisotropic Orbital Symmetry

abstract:
  We revisit the formulations and simulations of angular distributions in
polarization-dependent core-level photoemission spectra of strongly correlated
electron systems, in order to explain the recently discovered linear dichroism
(LD) in the core-level photoemission of 4f-based rare-earth compounds. Owing to
the selection rules for the optical process of core-level excitations, the LD
originating from the anisotropic outer localized charge distributions
determined by the ground-state orbital symmetry can be observed. Our
simulations show that core d-level excitations are essential for the LD in
localized ions having a cubic symmetry, which is absent in the p-orbital
excitations.


title: Chinese/English mixed Character Segmentation as Semantic Segmentation

abstract:
  OCR character segmentation for multilingual printed documents is difficult
due to the diversity of different linguistic characters. Previous approaches
mainly focus on monolingual texts and are not suitable for multilingual-lingual
cases. In this work, we particularly tackle the Chinese/English mixed case by
reframing it as a semantic segmentation problem. We take advantage of the
successful architecture called fully convolutional networks (FCN) in the field
of semantic segmentation. Given a wide enough receptive field, FCN can utilize
the necessary context around a horizontal position to determinate whether this
is a splitting point or not. As a deep neural architecture, FCN can
automatically learn useful features from raw text line images. Although trained
on synthesized samples with simulated random disturbance, our FCN model
generalizes well to real-world samples. The experimental results show that our
model significantly outperforms the previous methods.


title:
Antiprotons from dark matter annihilation through light mediators and a
  possible excess in AMS-02 $\bar{p}/p$ data

abstract:
  We show that in the scenario where dark matter (DM) particles annihilate
through light mediators, the energy spectra of the final state cosmic-ray
particles depend strongly on the mediator mass. For final state antiprotons, a
spectrum with relatively narrow peak occurs when the mediator mass is
comparable to the $\pbar p$ production threshold. Of interest, the latest
AMS-02 data on the $\pbar/p$ flux ratio hint at a bump-like excess over the
expected background in the energy range $\sim100-450$ GeV. We show that such a
light mediator scenario is favoured by the latest AMS-02 data over the
scenarios of DM direct annihilation into the standard model particles and that
of antiprotons produced from inside supernova remnants (SNRs), and is
consistent with the upper limits derived from the Fermi-LAT data on the gamma
rays towards the dwarf spheroidal galaxies. The $\pbar/p$ flux ratio with
energy above 450 GeV is predicted to fall with energy quickly, which can be
easily distinguished from the other two scenarios as they predict the ratio to
be flattening or rising up to multi-TeV region.


title:
Compactness results for static and dynamic chiral skyrmions near the
  conformal limit

abstract:
  We examine lower order perturbations of the harmonic map prob- lem from
$\mathbb{R}^2$ to $\mathbb{S}^2$ including chiral interaction in form of a
helicity term that prefers modulation, and a potential term that enables decay
to a uniform background state. Energy functionals of this type arise in the
context of magnetic systems without inversion symmetry. In the almost conformal
regime, where these perturbations are weighted with a small parameter, we
examine the existence of relative minimizers in a non-trivial homotopy class,
so-called chiral skyrmions, strong compactness of almost minimizers, and their
asymptotic limit. Finally we examine dynamic stability and compactness of
almost minimizers in the context of the Landau-Lifshitz-Gilbert equation
including spin-transfer torques arising from the interaction with an external
current.


title:
Cooperative Simultaneous Localization and Synchronization in Mobile
  Agent Networks

abstract:
  Cooperative localization in agent networks based on interagent time-of-flight
measurements is closely related to synchronization. To leverage this relation,
we propose a Bayesian factor graph framework for cooperative simultaneous
localization and synchronization (CoSLAS). This framework is suited to mobile
agents and time-varying local clock parameters. Building on the CoSLAS factor
graph, we develop a distributed (decentralized) belief propagation algorithm
for CoSLAS in the practically important case of an affine clock model and
asymmetric time stamping. Our algorithm allows for real-time operation and is
suitable for a time-varying network connectivity. To achieve high accuracy at
reduced complexity and communication cost, the algorithm combines particle
implementations with parametric message representations and takes advantage of
a conditional independence property. Simulation results demonstrate the good
performance of the proposed algorithm in a challenging scenario with
time-varying network connectivity.


title:
Competition of superconductivity with the structural transition in
  Mo3Sb7

abstract:
  Prior to the superconducting transition at Tc = 2.3 K, Mo3Sb7 undergoes a
symmetry-lowering, cubic-to-tetragonal structural transition at Ts = 53 K. We
have monitored the pressure dependence of these two transitions by measuring
the resistivity of Mo3Sb7 single crystals under various hydrostatic pressures
up to 15 GPa. The application of external pressure enhances Tc but suppresses
Ts until Pc ~ 10 GPa, above which a pressure-induced first order structural
transition takes place and is manifested by the phase coexistence in the
pressure range 8 < P < 12 GPa. The cubic phase above 12 GPa is also found to be
superconducting with a higher Tc =6 K that decreases slightly with further
increasing pressure. The variations with pressure of Tc and Ts satisfy the
Bilbro-McMillan equation, i.e. Tc^nTs^(1-n) = constant, thus suggesting the
competition of superconductivity with the structural transition that has been
proposed to be accompanied with a spin-gap formation at Ts. This scenario is
supported by our first-principles calculations which imply the plausible
importance of magnetism that competes with the superconductivity in Mo3Sb7.


title: $B_c$ decays from highly improved staggered quarks and NRQCD

abstract:
  We calculate semileptonic form factors for the decays $B_c \to \eta_c \, l
\nu$ and $B_c \to J/\psi \, l \nu$ over the entire $q^2$ range, using a highly
improved lattice quark action for charm at several lattice spacings down to
$a=0.045$ fm. We have two ways of treating the $b$ quark: either with an
$O(\alpha_s)$ improved NRQCD formalism or by extrapolating a heavy mass $m_h$
to $m_b$ in the relativistic formalism. Comparison of the two approaches
provides an important cross-check of methodologies in lattice QCD.
Nonperturbative renormalisation of the currents in the relativistic theory also
allows us then to fix NRQCD-charm normalisation for $b$ to $c$ decays such as
$B \to D$ and $B \to D^*$.


title: Differentiable Functional Program Interpreters

abstract:
  Programming by Example (PBE) is the task of inducing computer programs from
input-output examples. It can be seen as a type of machine learning where the
hypothesis space is the set of legal programs in some programming language.
Recent work on differentiable interpreters relaxes the discrete space of
programs into a continuous space so that search over programs can be performed
using gradient-based optimization. While conceptually powerful, so far
differentiable interpreter-based program synthesis has only been capable of
solving very simple problems. In this work, we study modeling choices that
arise when constructing a differentiable programming language and their impact
on the success of synthesis. The main motivation for the modeling choices comes
from functional programming: we study the effect of memory allocation schemes,
immutable data, type systems, and built-in control-flow structures. Empirically
we show that incorporating functional programming ideas into differentiable
programming languages allows us to learn much more complex programs than is
possible with existing differentiable languages.


title: DeepCoder: Learning to Write Programs

abstract:
  We develop a first line of attack for solving programming competition-style
problems from input-output examples using deep learning. The approach is to
train a neural network to predict properties of the program that generated the
outputs from the inputs. We use the neural network's predictions to augment
search techniques from the programming languages community, including
enumerative search and an SMT-based solver. Empirically, we show that our
approach leads to an order of magnitude speedup over the strong non-augmented
baselines and a Recurrent Neural Network approach, and that we are able to
solve problems of difficulty comparable to the simplest problems on programming
competition websites.


title: Hamiltonian operator for spectral shape analysis

abstract:
  Many shape analysis methods treat the geometry of an object as a metric space
that can be captured by the Laplace-Beltrami operator. In this paper, we
propose to adapt the classical Hamiltonian operator from quantum mechanics to
the field of shape analysis. To this end we study the addition of a potential
function to the Laplacian as a generator for dual spaces in which shape
processing is performed. We present a general optimization approach for solving
variational problems involving the basis defined by the Hamiltonian using
perturbation theory for its eigenvectors. The suggested operator is shown to
produce better functional spaces to operate with, as demonstrated on different
shape analysis tasks.


title: Criticality and mechanical enhancement in composite fibre networks

abstract:
  Many biological materials consist of sparse networks of disordered fibres,
embedded in a soft elastic matrix. The interplay between rigid and soft
elements in such composite networks leads to mechanical properties that can go
far beyond the sum of those of the constituents. Here we present lattice-based
simulations to unravel the microscopic origins of this mechanical synergy. We
show that the competition between fibre stretching and bending and elastic
deformations of the matrix gives rise to distinct mechanical regimes, with
phase transitions between them that are characterized by critical behaviour and
diverging strain fluctuations and with different mechanisms leading to
mechanical enhancement.


title: Simple finite-dimensional double algebras

abstract:
  A double algebra is a linear space $V$ equipped with linear map $V\otimes
V\to V\otimes V$. Additional conditions on this map lead to the notions of Lie
and associative double algebras. We prove that simple finite-dimensional Lie
double algebras do not exist over an arbitrary field, and all simple
finite-dimensional associative double algebras over an algebraically closed
field are trivial.
  Over an arbitrary field, every simple finite-dimensional associative double
algebra is commutative. A double algebra structure on a finite-dimensional
space $V$ is naturally described by a linear operator $R$ on the algebra $\End
V$ of linear transformations of~$V$. Double Lie algebras correspond in this
sense to skew-symmetric Rota---Baxter operators, double associative algebra
structures---to (left) averaging operators.


title: Second law, Landauer's Principle and Autonomous information machine

abstract:
  Second law of thermodynamics can be apparently violated for systems whose
dynamics depends on acquired information by measurement. However, when one
consider measurement and erasure process together along with the system it
saves the second law. We consider a simple example of information machine where
information is used as a resource to increase its performance. The system is
connected to two baths, a work source and a moving tape which is used as an
information reservoir. The performance of the device is autonomous. The system
acts as an engine, erasure or refrigerator. Even combination of any two is
possible. All these possibilities are allowed by generalized second law.


title:
Broadband frequency comb generation in aluminum nitride-on-sapphire
  microresonators

abstract:
  Development of chip-scale optical frequency comb with the coverage from
ultra-violet (UV) to mid-infrared (MIR) wavelength is of great significance. To
expand the comb spectrum into the challenging UV region, a material platform
with high UV transparency is crucial. In this paper, crystalline aluminum
nitride (AlN)-onsapphire film is demonstrated for efficient Kerr frequency comb
generation. Near-infrared (NIR) comb with nearly octave-spanning coverage and
low parametric threshold is achieved in continuous-wave pumped
high-quality-factor AlN microring resonators. The competition between
stimulated Raman scattering (SRS) and hyperparametric oscillation is
investigated, along with broadband comb generation via Raman-assisted four-wave
mixing (FWM). Thanks to its wide bandgap, excellent crystalline quality as well
as intrinsic quadratic and cubic susceptibilities, AlN-on-sapphire platform
should be appealing for integrated nonlinear optics from MIR to UV region.


title:
Magnetic-dipole-to-electric-quadrupole cross-susceptibilities for
  relativistic hydrogenlike atoms in some low-lying discrete energy eigenstates

abstract:
  In this paper we present tabulated data for
magnetic-dipole-to-electric-quadrupole cross-susceptibilities
($\chi_{\textrm{M}1 \to \textrm{E}2}$) for Dirac one-electron atoms with a
pointlike, spinless and motionless nucleus of charge $Ze$. Numerical values of
this susceptibility for the hydrogen atom ($Z=1$) and for hydrogenic ions with
$2 \leqslant Z \leqslant 137$ are computed from the general analytical formula,
recently derived by us [P. Stefa{\'n}ska, Phys. Rev. A 93 (2016) 022504], valid
for an arbitrary discrete energy eigenstate. In this work we provide 30 tables
with the values of $\chi_{\textrm{M}1 \to \textrm{E}2}$ for the ground state,
and also for the first, the second and the third set of excited states (i.e.:
2s$_{1/2}$, 2p$_{1/2}$, 2p$_{3/2}$, 3s$_{1/2}$, 3p$_{1/2}$, 3p$_{3/2}$,
3d$_{3/2}$, 3d$_{5/2}$, 4s$_{1/2}$, 4p$_{1/2}$, 4p$_{3/2}$, 4d$_{3/2}$,
4d$_{5/2}$, 4f$_{5/2}$ and 4f$_{7/2}$) of the relativistic hydrogenlike atoms.
The value of the inverse of the fine-structure constant used in the
calculations is $\alpha^{-1}=137.035 \: 999 \: 139$, and was taken from CODATA
2014.


title: The Topology and Geometry of Hyperk\"ahler Quotients

abstract:
  In this thesis we study the topology and geometry of hyperk\"ahler quotients,
as well as some related non-compact K\"ahler quotients, from the point of view
of Hamiltonian group actions. The main technical tool we employ is Morse theory
with moment maps. We prove a Lojasiewicz inequality which permits the use of
Morse theory in the non-compact setting. We use this to deduce Kirwan
surjectivity for an interesting class of non-compact quotients, and obtain a
new proof of hyperk\"ahler Kirwan surjectivity for hypertoric varieties. We
then turn our attention to quiver varieties, obtaining an explicit inductive
procedure to compute the Betti numbers of the fixed-point sets of the natural
S^1 -action on these varieties. To study the kernel of the Kirwan map, we adapt
the Jeffrey-Kirwan residue formula to our setting. The residue formula may be
used to compute intersection pairings on certain compact subvarieties, and in
good cases these provide a complete description of the kernel of the
hyperk\"ahler Kirwan map. We illustrate this technique with several detailed
examples. Finally, we investigate the Poisson geometry of a certain family of
Nakajima varieties. We construct an explicit Lagrangian fibration on these
varieties by embedding them into Hitchin systems. This construction provides an
interesting class of toy models of Hitchin systems for which the hyperk\"ahler
metric may be computed explicitly.


title:
A variational approach to symmetry, monotonicity, and comparison for
  doubly-nonlinear equations

abstract:
  We advance a variational method to prove qualitative properties such as
symmetries, monotonicity, upper and lower bounds, sign properties, and
comparison principles for a large class of doubly-nonlinear evolutionary
problems including gradient flows, some nonlocal problems, and systems of
nonlinear parabolic equations.
  Our method is based on the so-called Weighted-Energy-Dissipation (WED)
variational approach. This consists in defining a global parameter-dependent
functional over entire trajectories and proving that its minimizers converge to
solutions to the target problem as the parameter goes to zero. Qualitative
properties and comparison principles can be easily proved for minimizers of the
WED functional and, by passing to the limit, for the limiting problem.
  Several applications of the abstract results to systems of nonlinear PDEs and
to fractional/nonlocal problems are presented. Eventually, we present some
extensions of this approach in order to deal with rate-independent systems and
hyperbolic problems.


title: Topological one-way fiber of second Chern number

abstract:
  Optical fiber is a ubiquitous and indispensable component in communications,
sensing, biomedicine and many other lightwave technologies and applications.
Here we propose topological one-way fibers to remove two fundamental mechanisms
that limit fiber performance: scattering and reflection. We design
three-dimensional~(3D) photonic crystal fibers, inside which photons propagate
only in one direction, that are completely immune to Rayleigh and Mie
scatterings and significantly suppress the nonlinear Brillouin and Raman
scatterings. A one-way fiber is also free from Fresnel reflection, naturally
eliminating the needs for fiber isolators. Our finding is enabled by the
recently discovered Weyl points in a double-gyroid~(DG) photonic crystal. By
annihilating two Weyl points by supercell modulation in a magnetic DG, we
obtain the photonic analogue of the 3D quantum Hall phase with a non-zero first
Chern number~($C_1$). When the modulation becomes helixes, one-way fiber modes
develop along the winding axis, with the number of modes determined by the
spatial frequency of the helix. These single-polarization single-mode and
multi-mode one-way fibers, having nearly identical group and phase velocities,
are topologically-protected by the second Chern number~($C_2$) in the 4D
parameter space of the 3D wavevectors plus the winding angle of the helixes.
This work suggests a unique way to utilize higher-dimensional topological
physics without resorting to artificial dimensions.


title:
A probabilistic model for the distribution of ranks of elliptic curves
  over $\mathbb{Q}$

abstract:
  In this article, we propose a new probabilistic model for the distribution of
ranks of elliptic curves in families of fixed Selmer rank, and compare the
predictions with previous results, and with the databases of curves over the
rationals that we have at our disposal. In addition, we document a phenomenon
we refer to as Selmer bias that seems to play an important role in the data and
in our models.


title: Transient dynamics of large scale vortices in Keplerian disk

abstract:
  The mechanism of transition from laminar state to turbulent state in
Keplerian disks is still unknown. The most popular version today is generation
of turbulence due to magnetorotational instability (MRI). However
magnetohydrodynamic simulations give the value of Shakura-Sunyaev parameter
more then an order of magnitude smaller rather than that found from
observations. One way to solve this problem is the existence of an alternative
or additional mechanism for generating turbulence. It can be the bypass
mechanism, which is responsible for transition to turbulence in Couette and
Poiseuille flows. This mechanism is based on the transient growth of linear
perturbations in the flow with the subsequent transition to the nonlinear
stage. In order to clarify the role of this mechanism in astrophysical disks
first of all it is necessary to calculate the maximal possible growth factor of
linear perturbations in the flow. In this paper the results of such
calculations are presented for perturbations on different scales compared with
the disk thickness. Qualitative description of mechanisms responsible for the
growth will also be presented. It was found that the most rapidly growing shear
harmonics have azimuthal wavelength of the order of the disk thickness. In
addition, their initial form is always similar to the vortex perturbations with
the same potential vorticity. It was shown that the vortices with azimuthal
wavelength more than an order of magnitude in excess of the disc thickness, are
still able to grow by dozens of times.


title:
Co-primary Spectrum Sharing for Inter-operator Device-to-Device
  Communication

abstract:
  The business potential of device-to-device (D2D) communication including
public safety and vehicular communications will be realized only if direct
communication between devices subscribed to different mobile operators (OPs) is
supported. One possible way to implement inter-operator D2D communication may
use the licensed spectrum of the OPs, i.e., OPs agree to share spectrum in a
co-primary manner, and inter-operator D2D communication is allocated over
spectral resources contributed from both parties. In this paper, we consider a
spectrum sharing scenario where a number of OPs construct a spectrum pool
dedicated to support inter-operator D2D communication. OPs negotiate in the
form of a non-cooperative game about how much spectrum each OP contributes to
the spectrum pool. OPs submit proposals to each other in parallel until a
consensus is reached. When every OP has a concave utility function on the
box-constrained region, we identify the conditions guaranteeing the existence
of a unique equilibrium point. We show that the iterative algorithm based on
the OP's best response might not converge to the equilibrium point due to
myopically overreacting to the response of the other OPs, while the Jacobi-play
strategy update algorithm can converge with an appropriate selection of update
parameter. Using the Jacobi-play update algorithm, we illustrate that
asymmetric OPs contribute an unequal amount of resources to the spectrum pool;
However all participating OPs may experience significant performance gains
compared to the scheme without spectrum sharing.


title: Maximal cliques structure for cocomparability graphs and applications

abstract:
  A cocomparability graph is a graph whose complement admits a transitive
orientation. An interval graph is the intersection graph of a family of
intervals on the real line. In this paper we investigate the relationships
between interval and cocomparability graphs. This study is motivated by recent
results Corneil,Dalton, Habib (2013) and Dusart, Habib (2016) and that show
that for some problems, the algorithm used on interval graphs can also be used
with small modifications on cocomparability graphs. Many of these algorithms
are based on graph searches that preserve cocomparability orderings.
  First we propose a characterization of cocomparability graphs via a lattice
structure on the set of their maximal cliques. Using this characterization we
can prove that every maximal interval subgraph of a cocomparability graph $G$
is also a maximal chordal subgraph of $G$. Although the size of this lattice of
maximal cliques can be exponential in the size of the graph, it can be used as
a framework to design and prove algorithms on cocomparability graphs. In
particular we show that a new graph search, namely Local Maximal Neighborhood
Search (LocalMNS) leads to an $O(n+mlogn)$ time algorithm to find a maximal
interval subgraph of a cocomparability graph. Similarly we propose a linear
time algorithm to compute all simplicial vertices in a cocomparability graph.
In both cases we improve on the current state of knowledge.


title: Sturm 3-ball global attractors 1: Thom-Smale complexes and meanders

abstract:
  This is the first of three papers on the geometric and combinatorial
characterization of global Sturm attractors which consist of a single closed
3-ball. The underlying scalar PDE is parabolic, $$ u_t = u_{xx} + f(x,u,u_x)\,,
$$ on the unit interval $0 < x<1$ with Neumann boundary conditions. Equilibria
are assumed to be hyperbolic. Geometrically, we study the resulting Thom-Smale
dynamic complex with cells defined by the unstable manifolds of the equilibria.
The Thom-Smale complex turns out to be a regular cell complex. Our geometric
description involves a bipolar orientation of the 1-skeleton, a hemisphere
decomposition of the boundary 2-sphere by two polar meridians, and a meridian
overlap of certain 2-cell faces in opposite hemispheres. The combinatorial
description is in terms of the Sturm permutation, alias the meander properties
of the shooting curve for the equilibrium ODE boundary value problem. It
involves the relative positioning of extreme 2-dimensionally unstable
equilibria at the Neumann boundaries $x=0$ and $x=1$, respectively, and the
overlapping reach of polar serpents in the shooting meander. In the present
paper we show the implications $$ \text{Sturm attractor}\quad \Longrightarrow
\quad \text{Thom-Smale complex} \quad \Longrightarrow \quad \text{meander}\,.$$
The sequel, part 2, closes the cycle of equivalences by the implication $$
\text{meander} \quad \Longrightarrow \quad \text{Sturm attractor}\,.$$ Many
explicit examples will be discussed in part 3. The present 3-ball trilogy
extends our previous trilogy on planar Sturm global attractors towards the
still elusive goal of geometric and combinational characterizations of all
Sturm global attractors of arbitrary dimension.


title:
Detecting metrologically useful asymmetry and entanglement by a few
  local measurements

abstract:
  Important properties of a quantum system are not directly measurable, but
they can be disclosed by how fast the system changes under controlled
perturbations. In particular, asymmetry and entanglement can be verified by
reconstructing the state of a quantum system. Yet, this usually requires
experimental and computational resources which increase exponentially with the
system size. Here we show how to detect metrologically useful asymmetry and
entanglement by a limited number of measurements. This is achieved by studying
how they affect the speed of evolution of a system under a unitary
transformation. We show that the speed of multiqubit systems can be evaluated
by measuring a set of local observables, providing exponential advantage with
respect to state tomography. Indeed, the presented method requires neither the
knowledge of the state and the parameter-encoding Hamiltonian nor global
measurements performed on all the constituent subsystems. We implement the
detection scheme in an all-optical experiment.


title: First passage percolation in Euclidean space and on random tessellations

abstract:
  There are various models of first passage percolation (FPP) in $\mathbb R^d$.
We want to start a very general study of this topic. To this end we generalize
the first passage percolation model on the lattice $\mathbb Z^d$ to $\mathbb
R^d$ and adapt the results of \cite{boivin1990first} to prove a shape theorem
for ergodic random pseudometrics on $\mathbb R^d$. A natural application of
this result will be the study of FPP on random tessellations where a fluid
starts in the zero cell and takes a random time to pass through the boundary of
a cell into a neighbouring cell. We find that a tame random tessellation, as
introduced in the companion paper \cite{ziesche2016bernoulli}, has a positive
time constant. This is used to derive a spatial ergodic theorem for the graph
induced by the tessellation. Finally we take a look at the Poisson hyperplane
tessellation, give an explicit formula to calculate it's FPP limit shape and
bound the speed of convergence in the corresponding shape theorem.


title: Two types of phase diagrams for two-species Bose-Einstein condensates

abstract:
  Under the Thomas-Fermi approximation, a relatively much simpler analytical
solutions of the coupled Gross-Pitaevskii equations for the two-species BEC
have been derived. Additionally, a model for the asymmetric states has been
proposed, and the competition between the symmetric and asymmetric states has
been evaluated. The whole parameter-space is divided into zones, each supports
a specific phase, namely, the symmetric miscible phase, the symmetric
immiscible phase, or the asymmetric phase. Based on the division the
phase-diagrams against any set of parameters can be plotted. Thereby, the
effects of these parameters can be visualized. There are three critical values
in the inter-species interaction $% V_{AB} $ and one in the ratio of particle
numbers $N_{A}/N_{B}$. They govern the transitions between the phases. Two
cases, (i) the repulsive $V_{AB}$ matches the repulsive $% V_{A}+V_{B}$, and
(ii) the attractive $V_{AB}$ nearly cancels the effect of the repulsive
$V_{A}+V_{B}$ have been particularly taken into account. The former leads to a
complete separation of the two kinds of atoms , while the latter lead to a
collapse. Finally, based on an equation derived in the paper, a convenient
experimental approach is proposed to determine the ratio of particle numbers .


title: Keyphrase Annotation with Graph Co-Ranking

abstract:
  Keyphrase annotation is the task of identifying textual units that represent
the main content of a document. Keyphrase annotation is either carried out by
extracting the most important phrases from a document, keyphrase extraction, or
by assigning entries from a controlled domain-specific vocabulary, keyphrase
assignment. Assignment methods are generally more reliable. They provide
better-formed keyphrases, as well as keyphrases that do not occur in the
document. But they are often silent on the contrary of extraction methods that
do not depend on manually built resources. This paper proposes a new method to
perform both keyphrase extraction and keyphrase assignment in an integrated and
mutual reinforcing manner. Experiments have been carried out on datasets
covering different domains of humanities and social sciences. They show
statistically significant improvements compared to both keyphrase extraction
and keyphrase assignment state-of-the art methods.


title: Fluctuations for mean-field interacting age-dependent Hawkes processes

abstract:
  The propagation of chaos and associated law of large numbers for mean-field
interacting age-dependent Hawkes processes (when the number of processes n goes
to +$\infty$) being granted by the study performed in (Chevallier, 2015), the
aim of the present paper is to prove the resulting functional central limit
theorem. It involves the study of a measure-valued process describing the
fluctuations (at scale n --1/2) of the empirical measure of the ages around its
limit value. This fluctuation process is proved to converge towards a limit
process characterized by a limit system of stochastic differential equations
driven by a Gaussian noise instead of Poisson (which occurs for the law of
large numbers limit).


title:
Parity doubling of nucleons, Delta and Omega baryons across the
  deconfinement phase transition

abstract:
  In this work we analyse positive- and negative-parity channels for the
nucleon (spin $1/2$ octet), $\Delta$ and $\Omega$ baryons (spin $3/2$ decuplet)
using lattice QCD. In Nature, at zero temperature, chiral symmetry is
spontaneously broken, causing positive- and negative-parity ground states to
have different masses. However, chiral symmetry is expected to be restored (for
massless quarks) around the crossover temperature, implying that the two
opposite parity channels should become degenerate. Here we study what happens
in a temperature range which includes both the hadronic and the quark gluon
plasma (QGP) phase. By analysing the correlation and spectral functions via
exponential fits and the Maximum Entropy Method respectively, we have found
parity doubling for the nucleon and $\Delta$ baryon channels in the QGP phase.
For the $\Omega$ baryon we see a clear signal of parity doubling at the
crossover temperature, which is however not complete, due to the nonzero
strange quark mass. Moreover, in-medium effects in the hadronic phase are
evident for all three baryons, in particular for the negative-parity ground
states. This might have implications for the hadron resonance gas model. In
this work we used the FASTSUM anisotropic $N_f = 2 + 1$ ensembles.


title:
Convergence Analysis of Distributed Inference with Vector-Valued
  Gaussian Belief Propagation

abstract:
  This paper considers inference over distributed linear Gaussian models using
factor graphs and Gaussian belief propagation (BP). The distributed inference
algorithm involves only local computation of the information matrix and of the
mean vector, and message passing between neighbors. Under broad conditions, it
is shown that the message information matrix converges to a unique positive
definite limit matrix for arbitrary positive semidefinite initialization, and
it approaches an arbitrarily small neighborhood of this limit matrix at a
doubly exponential rate. A necessary and sufficient convergence condition for
the belief mean vector to converge to the optimal centralized estimator is
provided under the assumption that the message information matrix is
initialized as a positive semidefinite matrix. Further, it is shown that
Gaussian BP always converges when the underlying factor graph is given by the
union of a forest and a single loop. The proposed convergence condition in the
setup of distributed linear Gaussian models is shown to be strictly weaker than
other existing convergence conditions and requirements, including the Gaussian
Markov random field based walk-summability condition, and applicable to a large
class of scenarios.


title:
Persistent homoclinic tangencies and infinitely many sinks for residual
  sets of automorphisms of low degree in C^{3}

abstract:
  We show that there exists a polynomial automorphism $f$ of $\mathbb{C}^{3}$
of degree 2 such that for every automorphism $g$ sufficiently close to $f$, $g$
admits a tangency between the stable and unstable laminations of some
hyperbolic set. As a consequence, for each $d \ge 2$, there exists an open set
of polynomial automorphisms of degree at most $d$ in which the automorphisms
having infinitely many sinks are dense. To prove these results, we give a
complex analogous to the notion of blender introduced by Bonatti and Diaz.


title: Bijection between oriented maps and weighted non-oriented maps

abstract:
  We consider bicolored maps, i.e. graphs which are drawn on surfaces, and
construct a bijection between (i) oriented maps with arbitary face structure,
and (ii) (weighted) non-oriented maps with exactly one face. Above, each
non-oriented map is counted with a multiplicity which is based on the concept
of the orientability generating series and the measure of orientability of a
map. This bijection has the remarkable property of preserving the underlying
bicolored graph. Our bijection shows equivalence between two explicit formulas
for the top-degree of Jack characters, i.e. (suitably normalized) coefficients
in the expansion of Jack symmetric functions in the basis of power-sum
symmetric functions.


title: Vacuum self similar anisotropic cosmologies in $F(R)-$gravity

abstract:
  The implications from the existence of a proper Homothetic Vector Field (HVF)
on the dynamics of vacuum anisotropic models in $F(R)$ gravitational theory are
studied. The fact that \emph{every} Spatially Homogeneous vacuum model is
equivalent, formally, with a "flux" -free anisotropic fluid model in standard
gravity and the induced power-law form of the functional $F(R)$ due to
self-similarity enable us to close the system of equations. We found some new
exact anisotropic solutions that arise as fixed points in the associated
dynamical system. The non-existence of Kasner-like (Bianchi type I) solutions
in proper $F(R)-$gravity (i.e. $R\neq 0$) strengthens the belief that curvature
corrections will prevent the shear influence into the past thus permitting an
isotropic singularity. We also discuss certain issues regarding the lack of
vacuum models of type III, IV, VII$_{h}$ in comparison with the corresponding
results in standard gravity.


title: Swimming by switching

abstract:
  In this paper we investigate different strategies to overcome the scallop
theorem. We will show how to obtain a net motion exploiting the fluid's type
change during a periodic deformation. We are interested in two different
models: in the first one that change is linked to the magnitude of the opening
and closing velocity. Instead, in the second one it is related to the sign of
the above velocity. An interesting feature of the latter model is the
introduction of a delay-switching rule through a thermostat. We remark that the
latter is fundamental in order to get both forward and backward motion.


title: An analysis of New South Wales electronic vote counting

abstract:
  We re-examine the 2012 local government elections in New South Wales,
Australia. The count was conducted electronically using a randomised form of
the Single Transferable Vote (STV). It was already well known that randomness
does make a difference to outcomes in some seats. We describe how the process
could be amended to include a demonstration that the randomness was chosen
fairly.
  Second, and more significantly, we found an error in the official counting
software, which caused a mistake in the count in the council of Griffith, where
candidate Rina Mercuri narrowly missed out on a seat. We believe the software
error incorrectly decreased Mercuri's winning probability to about
10%---according to our count she should have won with 91% probability.
  The NSW Electoral Commission (NSWEC) corrected their code when we pointed out
the error, and made their own announcement.
  We have since investigated the 2016 local government election (held after
correcting the error above) and found two new errors. We notified the NSWEC
about these errors a few days after they posted the results.


title:
Small-angle scattering studies of intrinsically disordered proteins and
  their complexes

abstract:
  Intrinsically Disordered Proteins (IDPs) perform a broad range of biological
functions. Their relevance has motivated intense research activity seeking to
characterize their sequence/structure/function relationships. However, the
conformational plasticity of these molecules hampers the application of
traditional structural approaches, and new tools and concepts are being
developed to address the challenges they pose. Small-Angle Scattering (SAS) is
a structural biology technique that probes the size and shape of disordered
proteins and their complexes with other biomolecules. The low-resolution nature
of SAS can be compensated with specially designed computational tools and its
combined interpretation with complementary structural information. In this
review, we describe recent advances in the application of SAS to disordered
proteins and highly flexible complexes and discuss current challenges.


title: Representation embeddings and the second Brauer-Thrall conjecture

abstract:
  We prove that over an algebraically closed field there is a representation
embedding from the category of classical Kronecker-modules without the simple
injective into the category of finite-dimensional modules over any
representation-infinite finite-dimensional algebra. We also sharpen some known
results on representation embeddings, we simplify some proofs and we construct
a simultaneous orthogonal embedding for an infinite family of module
categories. In the last section the minimal classes of representation-infinite
algebras are determined. The result depends on the characteristic.


title:
Anomalies in local Weyl laws and applications to random topology at
  critical dimension

abstract:
  Let $\mathcal{M}$ be a smooth manifold of positive dimension $n$ equipped
with a smooth density $d\mu_{\mathcal{M}}$. Let $A$ be a polyhomogeneous
elliptic pseudo-differential operator of positive order $m$ on $\mathcal{M}$
which is symmetric for the $L^2$ scalar product defined by
$d\mu_{\mathcal{M}}$. For each $L>0$, the space $U_L=\bigoplus_{\lambda\leq
L}Ker(A-\lambda Id)$ is a finite dimensional subspace of
$C^\infty(\mathcal{M})$. Let $\Pi_L$ be the spectral projector onto $U_L$.
Given $s\in\mathbb{R}$, we compute the asymptotics of the integral kernel $K_L$
of $\Pi_LA^{-s}$ in the cases where $n>ms$ and $n=ms$ respectively. Next,
assuming that $\mathcal{M}$ is closed, let $(e_n)_{n\in\mathbb{N}}$ and
$(\lambda_n)_{n\in\mathbb{N}}$ be the sequence of $L^2$ normalized
eigenfunctions and eigenvalues of $A$ where the latter sequence organized in
increasing order. Let $(\xi_n)_{n\in\mathbb{N}}$ be a sequence of independent
centered gaussians of variance $1$. We fix a parameter $s\in\mathbb{R}$ such
that $n\geq ms$ and consider the family $(\phi_L)_{L>0}$ of smooth random
fields on $\mathcal{M}$ defined by \[\phi_L=\sum_{0<\lambda_j\leq
L}\lambda_j^{-\frac{s}{2}}\xi_je_j\] for each $L>0$. It turns out that the
covariance function of $\phi_L$ is $K_L$. Using this information, we apply the
derived asymptotics to study the zero set of $\phi_L$. If $n>ms$ then the
number of components of the zero set of $\phi_L$ concentrates around
$aL^{\frac{n}{m}}$ for some positive constant $a$. On the other hand, if
$n=ms$, each Betti number of the zero set has an expectation bounded by
$C\ln\Big(L^{\frac{1}{m}}\Big)^{-\frac{1}{2}}L^{\frac{n}{m}}$ where $C$ is an
explicit constant. When $\mathcal{M}$ is a closed surface with a Riemmanian
metric, $A$ is the Laplacian and $d\mu_\mathcal{M}$ is the Riemmanian volume,
$C$ equals $\frac{1}{4\pi^2}\sqrt{\frac{3}{2}}Vol(\mathcal{M})$.


title: Multi-view Generative Adversarial Networks

abstract:
  Learning over multi-view data is a challenging problem with strong practical
applications. Most related studies focus on the classification point of view
and assume that all the views are available at any time. We consider an
extension of this framework in two directions. First, based on the BiGAN model,
the Multi-view BiGAN (MV-BiGAN) is able to perform density estimation from
multi-view inputs. Second, it can deal with missing views and is able to update
its prediction when additional views are provided. We illustrate these
properties on a set of experiments over different datasets.


title: Purcell magneto-elastic swimmer controlled by an external magnetic field

abstract:
  This paper focuses on the mechanism of propulsion of a Purcell swimmer whose
segments are magnetized and react to an external magnetic field applied into
the fluid. By an asymptotic analysis, we prove that it is possible to steer the
swimmer along a chosen direction when the control functions are prescribed as
an oscillating field. Moreover, we discuss what are the main obstructions to
overcome in order to get classical controllability result for this system.


title: Decomposing the vertex set of a hypercube into isomorphic subgraphs

abstract:
  Let $G$ be an induced subgraph of the hypercube $Q_k$ for some $k$. We show
that if $|G|$ is a power of $2$ then, for sufficiciently large $n$, the vertex
set of $Q_n$ can be partitioned into induced copies of $G$. This answers a
question of Offner. In fact, we prove a stronger statement: if $X$ is a subset
of $\{0,1\}^k$ for some $k$ and if $|X|$ is a power of $2$, then, for
sufficiently large $n$, $\{0,1\}^n$ can be partitioned into isometric copies of
$X$.


title: Mass anomalous dimension of SU(2) using the spectral density method

abstract:
  SU(2) with N_f = 6 and N_f = 8 are believed to have an infrared conformal
fixed point. We use the spectral density method cross referenced with the mass
step scaling method to evaluate the coupling constant dependence of the mass
anomalous dimension for massless HEX smeared, clover improved Wilson fermions
with Schr\"odinger functional boundary conditions.


title:
Mean Field Type Control with Congestion (II): An Augmented Lagrangian
  Method

abstract:
  This work deals with a numerical method for solving a mean-field type control
problem with congestion. It is the continuation of an article by the same
authors, in which suitably defined weak solutions of the system of partial
differential equations arising from the model were discussed and existence and
uniqueness were proved. Here, the focus is put on numerical methods: a monotone
finite difference scheme is proposed and shown to have a variational
interpretation. Then an Alternating Direction Method of Multipliers for solving
the variational problem is addressed. It is based on an augmented Lagrangian.
Two kinds of boundary conditions are considered: periodic conditions and more
realistic boundary conditions associated to state constrained problems. Various
test cases and numerical results are presented.


title: Sigma Delta Quantized Networks

abstract:
  Deep neural networks can be obscenely wasteful. When processing video, a
convolutional network expends a fixed amount of computation for each frame with
no regard to the similarity between neighbouring frames. As a result, it ends
up repeatedly doing very similar computations. To put an end to such waste, we
introduce Sigma-Delta networks. With each new input, each layer in this network
sends a discretized form of its change in activation to the next layer. Thus
the amount of computation that the network does scales with the amount of
change in the input and layer activations, rather than the size of the network.
We introduce an optimization method for converting any pre-trained deep network
into an optimally efficient Sigma-Delta network, and show that our algorithm,
if run on the appropriate hardware, could cut at least an order of magnitude
from the computational cost of processing video data.


title: Presenting a New Dataset for the Timeline Generation Problem

abstract:
  The timeline generation task summarises an entity's biography by selecting
stories representing key events from a large pool of relevant documents. This
paper addresses the lack of a standard dataset and evaluative methodology for
the problem. We present and make publicly available a new dataset of 18,793
news articles covering 39 entities. For each entity, we provide a gold standard
timeline and a set of entity-related articles. We propose ROUGE as an
evaluation metric and validate our dataset by showing that top Google results
outperform straw-man baselines.


title:
Pricing Derivatives in a Regime Switching Market with Time Inhomogeneous
  Volatility

abstract:
  This paper studies pricing derivatives in an age-dependent semi-Markov
modulated market. We consider a financial market where the asset price dynamics
follow a regime switching geometric Brownian motion model in which the
coefficients depend on finitely many age-dependent semi-Markov processes. We
further allow the volatility coefficient to depend on time explicitly. Under
these market assumptions, we study locally risk minimizing pricing of a class
of European options. It is shown that the price function can be obtained by
solving a non-local B-S-M type PDE. We establish existence and uniqueness of a
classical solution of the Cauchy problem. We also find another characterization
of price function via a system of Volterra integral equation of second kind.
This alternative representation leads to computationally efficient methods for
finding price and hedging. Finally, we analyze the PDE to establish continuous
dependence of the solution on the instantaneous transition rates of semi-Markov
processes. An explicit expression of quadratic residual risk is also obtained.


title:
:telephone::person::sailboat::whale::okhand:; or "Call me Ishmael" - How
  do you translate emoji?

abstract:
  We report on an exploratory analysis of Emoji Dick, a project that leverages
crowdsourcing to translate Melville's Moby Dick into emoji. This distinctive
use of emoji removes textual context, and leads to a varying translation
quality. In this paper, we use statistical word alignment and part-of-speech
tagging to explore how people use emoji. Despite these simple methods, we
observed differences in token and part-of-speech distributions. Experiments
also suggest that semantics are preserved in the translation, and repetition is
more common in emoji.


title:
Self-consistent evaluation of effective Coulomb interaction of V atom
  and its importance to understand the comparative electronic behaviour of
  vanadium spinels

abstract:
  In present work, we try to understand the importance of effective Coulomb
interaction ($U_{ef}$) between localized electrons of V atom to understand the
comparative electronic behaviour of AV$_{2}$O$_{4}$ (A=Zn, Cd and Mg)
compounds. The suitable values of $d$-linearization energy ($E_{d}$) of
impurity V atom for calculating the $U_{ef}$ for these compounds are found to
be $\geq$44.89 eV above the Fermi level. Corresponding to these values of
$E_{d}$, the self-consistently calculated values of effective $U_{LSDA}$
($U_{PBEsol}$) for ZnV$_{2}$O$_{4}$, MgV$_{2}$O$_{4}$ and CdV$_{2}$O$_{4}$ are
$\sim$5.73 ($\sim$5.92), $\sim$6.06 ($\sim$6.22) and $\sim$5.59 ($\sim$5.71)
eV, respectively. The calculated values of $\frac{t}{U_{ef}}$ ($t$ is the
transfer integral between neighbouring sites) increases with decreasing V-V
distance from CdV$_{2}$O$_{4}$ to MgV$_{2}$O$_{4}$ to ZnV$_{2}$O$_{4}$ and are
found to be consistent with experimentally reported band gap. The values of
$\frac{t}{U_{ef}}$ for ZnV$_{2}$O$_{4}$, MgV$_{2}$O$_{4}$ and CdV$_{2}$O$_{4}$
are found to be $\sim$0.023, $\sim$0.020 and $\sim$0.018, respectively. Hence,
CdV$_{2}$O$_{4}$ with small (large) $\frac{t}{U_{ef}}$ (experimental band gap)
as compared to ZnV$_{2}$O$_{4}$ and MgV$_{2}$O$_{4}$ is found to be in
localized-electron regime, while ZnV$_{2}$O$_{4}$ and MgV$_{2}$O$_{4}$ are
intermediate between localized and an itinerant-electron regime. The calculated
values of lattice parameters $a_{LSDS}$ ($a_{PBEsol}$) are found to be
$\sim$1.7\%, $\sim$2.0\% and $\sim$2.4\% ($\sim$0.6\%, $\sim$0.7\% and
$\sim$0.7\%) smaller than $a_{exp}$ for CdV$_{2}$O$_{4}$, MgV$_{2}$O$_{4}$ and
ZnV$_{2}$O$_{4}$, respectively, which indicates that the PBEsol functional
predicts the lattice parameters in good agreement with the experimental data.


title:
Stellar magnetic activity and variability of oscillation parameters - An
  investigation of 24 solar-like stars observed by Kepler

abstract:
  Context. The Sun and solar-like stars undergo activity cycles for which the
underlying mechanisms are not well understood. The oscillations of the Sun are
known to vary with its activity cycle and these changes provide diagnostics on
the conditions below the photosphere. Kepler has detected oscillations in
hundreds of solar-like stars but as of yet, no widespread detection of
signatures of magnetic activity cycles in the oscillation parameters of these
stars have been reported.
  Aims. We analyse the photometric short cadence Kepler time series of a set of
24 solar-like stars, which were observed for at least 960 days each, with the
aim to find signatures of stellar magnetic activity in the oscillation
parameters.
  Methods. We analyse the temporal evolution of oscillation parameters by
measuring mode frequency shifts, changes in the height of the p-mode envelope,
as well as granulation time scales.
  Results. For 23 of the 24 investigated stars, we find significant frequency
shifts in time. We present evidence for magnetic activity in six of them. We
find that the amplitude of the frequency shifts decreases with stellar age and
rotation period. For the most prominent example, KIC 8006161, we find that,
similar to the solar case, frequency shifts are smallest for the lowest and
largest for the highest p-mode frequencies.
  Conclusions. These findings show that magnetic activity can be routinely
observed in the oscillation parameters for solar-like stars, which opens up the
possibility to place the solar activity cycle in the context of other stars by
asteroseismology.


title: Nonstandard cosmologies from physics beyond the Standard model

abstract:
  The modern cosmology is based on inflationary models with baryosynthesis and
dark matter/energy.It implies extension of particle symmetry beyond the
Standard model. Studies of physical basis of the modern cosmology combine
direct searches for new physics at accelerators with its indirect
non-accelerator probes, in which cosmological consequences of particle models
play important role. The cosmological consequences of particle models
inevitably go beyond the 'standard' cosmological $\Lambda$CDM model and some
possible feature of such 'nonstandard'cosmological scenarios is the subject of
the present brief review.


title:
Proton tracking in a high-granularity Digital Tracking Calorimeter for
  proton CT purposes

abstract:
  Radiation therapy with protons as of today utilizes information from x-ray CT
in order to estimate the proton stopping power of the traversed tissue in a
patient. The conversion from x-ray attenuation to proton stopping power in
tissue introduces range uncertainties of the order of 2-3% of the range,
uncertainties that are contributing to an increase of the necessary planning
margins added to the target volume in a patient. Imaging methods and
modalities, such as Dual Energy CT and proton CT, have come into consideration
in the pursuit of obtaining an as good as possible estimate of the proton
stopping power. In this study, a Digital Tracking Calorimeter is benchmarked
for proof-of-concept for proton CT purposes. The Digital Tracking Calorimeteris
applied for reconstruction of the tracks and energies of individual high energy
protons. The presented prototype forms the basis for a proton CT system using a
single technology for tracking and calorimetry. This advantage simplifies the
setup and reduces the cost of a proton CT system assembly, and it is a unique
feature of the Digital Tracking Calorimeter. Data from the AGORFIRM beamline at
KVI-CART in Groningen in the Netherlands and Monte Carlo simulation results are
used to in order to develop a tracking algorithm for the estimation of the
residual ranges of a high number of concurrent proton tracks. The range of the
individual protons can at present be estimated with a resolution of 4%. The
readout system for this prototype is able to handle an effective proton
frequency of 1 MHz by using 500 concurrent proton tracks in each readout frame,
which is at the high end range of present similar prototypes. A future further
optimized prototype will enable a high-speed and more accurate determination of
the ranges of individual protons in a therapeutic beam.


title: Large thermoelectric effect in ballistic Andreev interferometers

abstract:
  Employing quasiclassical theory of superconductivity combined with Keldysh
technique we investigate large thermoelectric effect in multiterminal ballistic
normal-superconducting (NS) hybrid structures. We argue that this effect is
caused by electron-hole asymmetry generated by coherent Andreev reflection of
quasiparticles at interfaces of two different superconductors with non-zero
phase difference. Within our model we derive a general expression for
thermoelectric voltages $V_{T1,2}$ induced in two different normal terminals
exposed to a thermal gradient. Our results apply at any temperature difference
in the subgap regime and allow to explicitly analyze both temperature and phase
dependencies of $V_{T1,2}$ demonstrating that in general there exists no
fundamental relation between these voltages and the equilibrium Josephson
current in SNS junctions.


title: Unintegrated double parton distributions

abstract:
  We present the construction of unintegrated double parton distribution
functions which include dependence on transverse momenta of partons. We extend
the formulation which was used to obtain the single unintegrated parton
distributions from the standard, integrated parton distribution functions.
Starting from the homogeneous part of the evolution equations for the
integrated double parton distributions, we construct the unintegrated double
parton distributions as the convolutions of the integrated double distributions
and the splitting functions, multiplied by the Sudakov form factors. We show
that there exist three domains of external hard scales which require three
distinct forms of the unintegrated double distributions. The additional
transverse momentum dependence which arises through the Sudakov form factors
leads to non-trivial correlations in the parton momenta. We also discuss the
non-homogeneous contribution to the unintegrated double parton distributions,
which arises due to the splitting of a single parton into daughter partons with
high transverse momenta. We analyze two cases, the unfolding of the transverse
momenta dependence from the last step of the evolution of two partons, and the
case where the transverse momenta are generated directly from the single parton
splitting.


title: Jet modules for the centerless Virasoro-like algebra

abstract:
  In this paper, we studied the jet modules for the centerless Virasoro-like
algebra which is the Lie algebra of the Lie group of the area-preserving
diffeomorphisms of a $2$-torus. The jet modules are certain natural modules
over the Lie algebra of semi-direct product of the centerless Virasoro-like
algebra and the Laurent polynomial algebra in two variables. We reduce the
irreducible jet modules to the finite-dimensional irreducible modules over some
infinite-dimensional Lie algebra and then characterize the irreducible jet
modules with irreducible finite dimensional modules over $\mathfrak{sl}_2$. To
determine the indecomposable jet modules, we use the technique of polynomial
modules in the sense of \cite{BB, BZ}. Consequently, indecomposable jet modules
are described using modules over the algebra $\BB_+$, which is the "positive
part" of a Block type algebra studied first by \cite{DZ} and recently by
\cite{IM, I}).


title:
All-optical switching in a continuously operated and strongly coupled
  atom-cavity system

abstract:
  We experimentally demonstrate collective strong coupling, optical
bi-stability (OB) and all-optical switching in a system consisting of ultracold
85Rb atoms, trapped in a dark magneto-optical trap (DMOT), coupled to an
optical Fabry-Perot cavity. The strong coupling is established by measuring the
vacuum Rabi splitting (VRS) of a weak on-axis probe beam. The dependence of VRS
on the probe beam power is measured and bi-stability in the cavity transmission
is observed. We demonstrate control over the transmission of the probe beam
through the atom-cavity system using a free-space off-axis control beam and
show that the cavity transmission can be switched on and off in micro-second
timescales using micro-Watt control powers. The utility of the system as a tool
for sensitive, in-situ and rapid measurements is envisaged.

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


title:
Gaia data release 1: Principles of the photometric calibration of the G
  band

abstract:
  Context. Gaia is an ESA cornerstone mission launched on 19 December 2013
aiming to obtain the most complete and precise 3D map of our Galaxy by
observing more than one billion sources. This paper is part of a series of
documents explaining the data processing and its results for Gaia Data Release
1, focussing on the G band photometry. Aims. This paper describes the
calibration model of the Gaia photometric passband for Gaia Data Release 1.
Methods. The overall principle of splitting the process into internal and
external calibrations is outlined. In the internal calibration, a
self-consistent photometric system is generated. Then, the external calibration
provides the link to the absolute photometric flux scales. Results. The Gaia
photometric calibration pipeline explained here was applied to the first data
release with good results. Details are given of the various calibration
elements including the mathematical formulation of the models used and of the
extraction and preparation of the required input parameters (e.g. colour
terms). The external calibration in this first release provides the absolute
zero point and photometric transformations from the Gaia G passband to other
common photometric systems. Conclusions. This paper describes the photometric
calibration implemented for the first Gaia data release and the instrumental
effects taken into account. For this first release no aperture losses,
radiation damage, and other second-order effects have not yet been implemented
in the calibration.


title: Landau-Zener Transitions in Spin Qubit Encoded in Three Quantum Dots

abstract:
  We study generation and dynamics of an exchange spin qubit encoded in three
coherently coupled quantum dots with three electrons. For two geometries of the
system a linear and a triangular one, the creation and coherent control of the
qubit states are performed by the Landau--Zener transitions. In the triangular
case both the qubit states are equivalent and can be easily generated for
particular symmetries of the system. If one of the dots is smaller than the
others one can observe Rabi oscillations, that can be used for coherent
manipulation of the qubit states. The linear system is easier to fabricate;
however, then the qubit states are not equivalent, making qubit operations more
difficult to control.