title: Sobolev-Lorentz spaces in the Euclidean setting and counterexamples

abstract:
  This paper studies the inclusions between different Sobolev-Lorentz spaces
$W^{1,(p,q)}(\Omega)$ defined on open sets $\Omega \subset {\mathbf{R}^n},$
where $n \ge 1$ is an integer, $1<p<\infty$ and $1 \le q \le \infty.$ We prove
that if $1 \le q<r \le \infty,$ then $W^{1,(p,q)}(\Omega)$ is strictly included
in $W^{1,(p,r)}(\Omega).$
  We show that although $H^{1,(p,\infty)}(\Omega) \subsetneq
W^{1,(p,\infty)}(\Omega)$ where $\Omega \subset {\mathbf{R}}^n$ is open and $n
\ge 1,$ there exists a partial converse. Namely, we show that if a function $u$
in $W^{1,(p,\infty)}(\Omega), n \ge 1$ is such that $u$ and its distributional
gradient $\nabla u$ have absolutely continuous $(p,\infty)$-norm, then $u$
belongs to $H^{1,(p,\infty)}(\Omega)$ as well.
  We also extend the Morrey embedding theorem to the Sobolev-Lorentz spaces
$H_{0}^{1,(p,q)}(\Omega)$ with $1 \le n<p<\infty$ and $1 \le q \le \infty.$
Namely, we prove that the Sobolev-Lorentz spaces $H_{0}^{1,(p,q)}(\Omega)$
embed into the space of H\"{o}lder continuous functions on $\overline{\Omega}$
with exponent $1-\frac{n}{p}$ whenever $\Omega \subset {\mathbf{R}}^n$ is open,
$1 \le n<p<\infty,$ and $1 \le q \le \infty.$


title:
Degrees of Freedom of $M\times N$ SISO X Channel with Synergistic
  Alternating CSIT

abstract:
  In this paper, degrees of freedom (DoF) is investigated for the $M\times N$
single input single output (SISO) X channel with alternating channel state
information at the transmitters (CSIT). It is known that the sum DoF of 2-user
SISO X channel with synergistic alternating CSIT is the same as the sum DoF of
2-user $(M=N=2)$ SISO X channel with perfect CSIT [8]. In this paper, such
2-user X channel schemes are extended to the general $M\times N$ X channel. It
is shown that the proposed $M\times N$ X channel schemes with synergistic
alternating CSIT achieve $2M/(M+1)$ sum DoF. This DoF with $M=N=K$ is strictly
lager than the best known DoF for the $K$-user X channel with delayed CSIT.


title: Promotion of Cooperation by Selective Group Extinction

abstract:
  Multilevel selection is an important organizing principle that crucially
underlies evolutionary processes from the emergence of cells to eusociality and
the economics of nations. Previous studies on multilevel selection assumed that
the effective higher-level selection emerges from lower-level reproduction.
This leads to selection among groups, although only individuals reproduce. We
introduce selective group extinction, where groups die with a probability
inversely proportional to their group fitness. When accounting for this the
critical benefit-to-cost ratio is substantially lowered. Because in game theory
and evolutionary dynamics the degree of cooperation crucially depends on this
ratio above which cooperation emerges previous studies may have substantially
underestimated the establishment and maintenance of cooperation.


title: An Overview of End-to-End Verifiable Voting Systems

abstract:
  Advances in E2E verifiable voting have the potential to fundamentally restore
trust in elections and democratic processes in society. In this chapter, we
provide a comprehensive introduction to the field. We trace the evolution of
privacy and verifiability properties in the research literature and describe
the operations of current state-of-the-art E2E voting systems. We also discuss
outstanding challenges to the deployment of E2E voting systems, including
technical, legal, and usability constraints.
  Our intention, in writing this chapter, has been to make the innovations in
this domain accessible to a wider audience. We have therefore eschewed
description of complex cryptographic mechanisms and instead attempt to
communicate the fundamental intuition behind the design of E2E voting systems.
We hope our work serves as a useful resource and assists in the future
development of E2E voting.


title:
Nonclassical light from a large number of independent single-photon
  emitters

abstract:
  Nonclassical quantum effects gradually reach domains of physics of large
systems previously considered as purely classical. We derive a hierarchy of
operational criteria suitable for a reliable detection of nonclassicality of
light from an arbitrarily large ensemble of independent single-photon emitters.
We show, that such large ensemble can always emit nonclassical light without
any phase reference and under realistic experimental conditions including
incoherent background noise. The nonclassical light from the large ensemble of
the emitters can be witnessed much better than light coming from a single or a
few emitters.


title:
Free-floating planets from core accretion theory: microlensing
  predictions

abstract:
  We calculate the microlensing event rate and typical time-scales for the
free-floating planet (FFP) population that is predicted by the core accretion
theory of planet formation. The event rate is found to be ~$1.8\times 10^{-3}$
of that for the stellar population. While the stellar microlensing event
time-scale peaks at around 20 days, the median time-scale for FFP events (~0.1
day) is much shorter. Our values for the event rate and the median time-scale
are significantly smaller than those required to explain the \cite{Sum+11}
result, by factors of ~13 and ~16, respectively. The inclusion of planets at
wide separations does not change the results significantly. This discrepancy
may be too significant for standard versions of both the core accretion theory
and the gravitational instability model to explain satisfactorily. Therefore,
either a modification to the planet formation theory is required, or other
explanations to the excess of short-time-scale microlensing events are needed.
Our predictions can be tested by ongoing microlensing experiment such as
KMTNet, and by future satellite missions such as WFIRST and Euclid.


title:
Measurement of the binding energy of ultracold $^{87}$Rb$^{133}$Cs
  molecules using an offset-free optical frequency comb

abstract:
  We report the binding energy of $^{87}$Rb$^{133}$Cs molecules in their
rovibrational ground state measured using an offset-free optical frequency comb
based on difference frequency generation technology. We create molecules in the
absolute ground state using stimulated Raman adiabatic passage (STIRAP) with a
transfer efficiency of 88\%. By measuring the absolute frequencies of our
STIRAP lasers, we find the energy-level difference from an initial weakly-bound
Feshbach state to the rovibrational ground state with a resolution of 5 kHz
over an energy-level difference of more than 114 THz; this lets us discern the
hyperfine splitting of the ground state. Combined with theoretical models of
the Feshbach state binding energies and ground-state hyperfine structure, we
determine a zero-field binding energy of $h\times114\,268\,135\,237(5)(50)$
kHz. To our knowledge, this is the most accurate determination to date of the
dissociation energy of a molecule.


title: High-dimensional peaks-over-threshold inference

abstract:
  Max-stable processes are increasingly widely used for modelling complex
extreme events, but existing fitting methods are computationally demanding,
limiting applications to a few dozen variables. $r$-Pareto processes are
mathematically simpler and have the potential advantage of incorporating all
relevant extreme events, by generalizing the notion of a univariate exceedance.
In this paper we investigate score matching for performing high-dimensional
peaks over threshold inference, focusing on extreme value processes associated
to log-Gaussian random functions and discuss the behaviour of the proposed
estimators for regularly-varying distributions with normalized marginals. Their
performance is assessed on grids with several hundred locations, simulating
from both the true model and from its domain of attraction. We illustrate the
potential and flexibility of our methods by modelling extreme rainfall on a
grid with $3600$ locations, based on risks for exceedances over local quantiles
and for large spatially accumulated rainfall, and briefly discuss diagnostics
of model fit. The differences between the two fitted models highlight the
importance of the choice of risk and its impact on the dependence structure.


title: Chemical Elements Abundance in the Universe and the Origin of Life

abstract:
  Element synthesis which started with p-p chain has resulted in several
specific characteristics including lack of any stable isotope having atomic
masses 5 or 8. The carbon to oxygen ratio is fixed early by the chain of
coincidences. These, remarkably fine-tuned, conditions are responsible for our
own existence and indeed the existence of any carbon based life in the
Universe. Chemical evolution of galaxies reflects in the changes of chemical
composition of stars, interstellar gas and dust. The evolution of chemical
element abundances in a galaxy provides a clock for galactic aging. On the
other hand, the living matter on the planet Earth needs only some elements for
its existence. Compared with element requirements of living matter a hypothesis
is put forward, by accepting the Anthropic Principle, which says: life as we
know, (H-C-N-O) based, relying on the number of bulk and trace elements
originated when two element abundance curves, living matter and galactic,
coincided. This coincidence occurring at particular redshift could indicates
the phase of the Universe when the life originated. It is proposed to look into
redshift region z = 0.5 to 2.5 (approximately t = -5.2x10E9 to -11.3x10E9
years) where many galaxies have been observed and to use these data to study
the evolution of metallicity with respect to the other properties of galaxies
in order to determine the time when universal element abundance curve coincided
with the element abundance curve of LUCA. The characteristic properties of the
latter have been transmitted by the genetic code while the universe element
abundance curve changed as the galaxies aged.


title:
A mean field equation involving positively supported probability
  measures: blow-up phenomena and variational aspects

abstract:
  We are concerned with an elliptic problem which describes a mean field
equation of the equilibrium turbulence of vortices with variable intensities.
  In the first part of the paper we describe the blow-up phenomenon and
highlight the differences from the standard mean field equation.
  In the second part we discuss the Moser-Trudinger inequality in terms of the
blow-up masses and get the existence of solutions in a non-coercive regime by
means of a variational argument, which is based on some improved
Moser-Trudinger inequalities.


title:
First step towards a Devil's Staircase in Spin Crossover materials First
  step towards Devil's Staircase in Spin Crossover materials

abstract:
  The devil is in the detail: Periodic and aperiodic spin-state concentration
waves form during "Devil's staircase"-type spincrossover in a new bimetallic 2D
coordination polymer {Fe[(Hg(SCN)3)2](4,4'-bipy)2}n.The unprecedented
bimetallic 2D coordination polymer {Fe[(Hg(SCN)3)2](4,4'-bipy)2}n exhibits a
thermal high-spin (HS)$low-spin (LS) staircase-like conversion characterized by
a multi-step dependence of the HS molar fraction gHS. Between the fully HS
(gHS=1) and LS (gHS=0) phases, two steps associated with different ordering
appear in terms of spin-state concentration waves (SSCW). On the gHS=0.5 step,
a periodic SSCW forms with a HS-LS-HS-LS sequence. On the gHS=0.34 step, the 4D
superspace crystallography structural refinement reveals an aperiodic SSCW,
with a HS-LS sequence incommensurate with the molecular lattice. The formation
of these different long-range spatially ordered structures of LS and HS states
during the multi-step spin-crossover is discussed within the framework of
"Devil's staircase"-type transitions. Spatially modulated phases are known in
various types of materials but are uniquely related to molecular HS/LS
bistability in this case.


title:
Dynamics and Statistics of the Fermi--Pasta--Ulam $\beta $--model with
  different ranges of particle interactions

abstract:
  In the present work we study the Fermi--Pasta--Ulam (FPU) $\beta $--model
involving long--range interactions (LRI) in both the quadratic and quartic
potentials, by introducing two independent exponents $\alpha_1$ and $\alpha_2$
respectively, which make the {forces decay} with distance $r$. Our results
demonstrate that weak chaos, in the sense of decreasing Lyapunov exponents, and
$q$--Gaussian probability density functions (pdfs) of sums of the momenta,
occurs only when long--range interactions are included in the quartic part.
More importantly, for $0\leq \alpha_2<1$, we obtain extrapolated values for $q
\equiv q_\infty >1$, as $N\rightarrow \infty$, suggesting that these pdfs
persist in that limit. On the other hand, when long--range interactions are
imposed only on the quadratic part, strong chaos and purely Gaussian pdfs are
always obtained for the momenta. We have also focused on similar pdfs for the
particle energies and have obtained $q_E$-exponentials (with $q_E>1$) when the
quartic-term interactions are long--ranged, otherwise we get the standard
Boltzmann-Gibbs weight, with $q=1$. The values of $q_E$ coincide, within small
discrepancies, with the values of $q$ obtained by the momentum distributions.


title:
Towards the Automated Verification of Cyber-Physical Security Protocols:
  Bounding the Number of Timed Intruders

abstract:
  Timed Intruder Models have been proposed for the verification of
Cyber-Physical Security Protocols (CPSP) amending the traditional Dolev-Yao
intruder to obey the physical restrictions of the environment. Since to learn a
message, a Timed Intruder needs to wait for a message to arrive, mounting an
attack may depend on where Timed Intruders are. It may well be the case that in
the presence of a great number of intruders there is no attack, but there is an
attack in the presence of a small number of well placed intruders. Therefore, a
major challenge for the automated verification of CPSP is to determine how many
Timed Intruders to use and where should they be placed. This paper answers this
question by showing it is enough to use the same number of Timed Intruders as
the number of participants. We also report on some preliminary experimental
results in discovering attacks in CPSP.


title: The role of ion transport phenomena in memristive double barrier devices

abstract:
  In this work we report on the role of ion transport for the dynamic behavior
of a double barrier quantum mechanical
Al/Al$_2$O$_3$/Nb$_{\text{x}}$O$_{\text{y}}$/Au memristive device based on
numerical simulations in conjunction with experimental measurements. The device
consists of an ultra-thin Nb$_{\text{x}}$O$_{\text{y}}$ solid state electrolyte
between an Al$_2$O$_3$ tunnel barrier and a semiconductor metal interface at an
Au electrode. It is shown that the device provides a number of interesting
features for potential applications such as an intrinsic current compliance, a
relatively long retention time, and no need for an initialization step.
Therefore, it is particularly attractive for applications in highly dense
random access memories or neuromorphic mixed signal circuits. However, the
underlying physical mechanisms of the resistive switching are still not
completely understood yet. To investigate the interplay between the current
transport mechanisms and the inner atomistic device structure a lumped element
circuit model is consistently coupled with 3D kinetic Monte Carlo model for the
ion transport. The simulation results indicate that the drift of charged point
defects within the Nb$_{\text{x}}$O$_{\text{y}}$ is the key factor for the
resistive switching behavior. It is shown in detail that the diffusion of
oxygen modifies the local electronic interface states resulting in a change of
the interface properties of the double barrier device.


title: Workload Equity in Vehicle Routing Problems: A Survey and Analysis

abstract:
  Over the past two decades, equity aspects have been considered in a growing
number of models and methods for vehicle routing problems (VRPs). Equity
concerns most often relate to fairly allocating workloads and to balancing the
utilization of resources, and many practical applications have been reported in
the literature. However, there has been only limited discussion about how
workload equity should be modeled in VRPs, and various measures for optimizing
such objectives have been proposed and implemented without a critical
evaluation of their respective merits and consequences.
  This article addresses this gap with an analysis of classical and alternative
equity functions for biobjective VRP models. In our survey, we review and
categorize the existing literature on equitable VRPs. In the analysis, we
identify a set of axiomatic properties that an ideal equity measure should
satisfy, collect six common measures, and point out important connections
between their properties and those of the resulting Pareto-optimal solutions.
To gauge the extent of these implications, we also conduct a numerical study on
small biobjective VRP instances solvable to optimality. Our study reveals two
undesirable consequences when optimizing equity with nonmonotonic functions:
Pareto-optimal solutions can consist of non-TSP-optimal tours, and even if all
tours are TSP optimal, Pareto-optimal solutions can be workload inconsistent,
i.e. composed of tours whose workloads are all equal to or longer than those of
other Pareto-optimal solutions. We show that the extent of these phenomena
should not be underestimated. The results of our biobjective analysis are valid
also for weighted sum, constraint-based, or single-objective models. Based on
this analysis, we conclude that monotonic equity functions are more appropriate
for certain types of VRP models, and suggest promising avenues for further
research.


title:
Fully coupled hybrid cavity optomechanics: quantum interferences and
  correlations

abstract:
  We present a quantum theory for a fully coupled hybrid optomechanical system
where all mutual couplings between a two-level atom, a confined photon mode and
a mechanical oscillator mode are considered. In such a configuration, new
quantum interference effects and correlations arise due to the interplay and
competition between the different physical interactions. We present an
analytical diagonalization of the related fully coupled Hamiltonian, showing
the nature and energy spectra of the tripartite dressed excitations. We
determine the driven-dissipative dynamics of such hybrid systems and study
phonon blockade effects under resonant excitation. We also study the
statistical properties of the photon emission obtained under incoherent pumping
of the two-level atom, which is particularly relevant for experiments with
solid-state two-level emitters.


title: Secure Containers in Android: the Samsung KNOX Case Study

abstract:
  Bring Your Own Device (BYOD) is a growing trend among enterprises, aiming to
improve workers' mobility and productivity via their smartphones. The threats
and dangers posed by the smartphones to the enterprise are also ever-growing.
Such dangers can be mitigated by running the enterprise software inside a
"secure container" on the smartphone. In our work we present a systematic
assessment of security critical areas in design and implementation of a secure
container for Android using reverse engineering and attacker-inspired methods.
We do this through a case-study of Samsung KNOX, a real-world product deployed
on millions of devices. Our research shows how KNOX security features work
behind the scenes and lets us compare the vendor's public security claims
against reality. Along the way we identified several design weaknesses and a
few vulnerabilities that were disclosed to Samsung.


title:
Computation of highly oscillatory Bessel transforms with algebraic
  singularities

abstract:
  In this paper, we consider the Clenshaw-Curtis-Filon method for the highly
oscillatory Bessel transform $\int_0^1x^\alpha (1-x)^\beta f(x) J_{\nu}(\omega
x)dx$, where $f$ is a smooth function on $[0, 1]$, and $\nu\geq0.$ The method
is based on Fast Fourier Transform (FFT) and fast computation of the modified
moments. We give a recurrence relation for the modified moments and present an
efficient method for the evaluation of modified moments by using recurrence
relation. Moreover, the corresponding error bound in inverse powers of $N$ for
this method for the integral is presented. Numerical examples are provided to
support our analysis and show the efficiency and accuracy of the method.


title: Quantum Hocus Pocus

abstract:
  The claims made in a manifesto resulting in the European quantum technologies
flagship initiative in quantum technology and similar enterprises are taken as
starting point to critically review some potential quantum resources, such as
coherent superposition and entanglement, and their potential usefulness for
parallelism and communication. Claims of absolute, irreducible (non-epistemic)
randomness are argued to be metaphysical. Cryptanalytic man-in-the-middle
attacks on quantum cryptography are well known to be feasible, but hardly
mentioned. If all of this is taken into account, a more sober perspective on
quantum capacities emerges, but one that may be ethically more justified than
the "hype and magic" that drives many current initiatives.


title: Driven Boson Sampling

abstract:
  Sampling the distribution of bosons that have undergone a random unitary
evolution is strongly believed to be a computationally hard problem. Key to
outperforming classical simulations of this task is to increase both the number
of input photons and the size of the network. We propose driven boson sampling,
in which photons are input within the network itself, as a means to approach
this goal. When using heralded single-photon sources based on parametric
down-conversion, this approach offers an $\sim e$-fold enhancement in the input
state generation rate over scattershot boson sampling, reaching the scaling
limit for such sources. More significantly, this approach offers a dramatic
increase in the signal-to-noise ratio with respect to higher-order photon
generation from such probabilistic sources, which removes the need for photon
number resolution during the heralding process as the size of the system
increases.


title: Structured contact force optimization for kino-dynamic motion generation

abstract:
  Optimal control approaches in combination with trajectory optimization have
recently proven to be a promising control strategy for legged robots.
Computationally efficient and robust algorithms were derived using simplified
models of the contact interaction between robot and environment such as the
linear inverted pendulum model (LIPM). However, as humanoid robots enter more
complex environments, less restrictive models become increasingly important. As
we leave the regime of linear models, we need to build dedicated solvers that
can compute interaction forces together with consistent kinematic plans for the
whole-body. In this paper, we address the problem of planning robot motion and
interaction forces for legged robots given predefined contact surfaces. The
motion generation process is decomposed into two alternating parts computing
force and motion plans in coherence. We focus on the properties of the momentum
computation leading to sparse optimal control formulations to be exploited by a
dedicated solver. In our experiments, we demonstrate that our motion generation
algorithm computes consistent contact forces and joint trajectories for our
humanoid robot. We also demonstrate the favorable time complexity due to our
formulation and composition of the momentum equations.


title: Coherent two-dimensional spectroscopy of a Fano model

abstract:
  The Fano lineshape arises from the interference of two excitation pathways to
reach a continuum. Its generality has resulted in a tremendous success in
explaining the lineshapes of many one-dimensional spectroscopies - absorption,
emission, scattering, conductance, photofragmentation - applied to very varied
systems - atoms, molecules, semiconductors and metals. Unravelling a
spectroscopy into a second dimension reveals the relationship between states in
addition to decongesting the spectra. Femtosecond-resolved two-dimensional
electronic spectroscopy (2DES) is a four-wave mixing technique that measures
the time-evolution of the populations, and coherences of excited states. It has
been applied extensively to the dynamics of photosynthetic units, and more
recently to materials with extended band-structures. In this letter, we solve
the full time-dependent third-order response, measured in 2DES, of a Fano model
and give the new system parameters that become accessible.


title: On the chemistry of hydrides of N atoms and O$^+$ ions

abstract:
  Previous work by various authors has suggested that the detection by
Herschel/HIFI of nitrogen hydrides along the low density lines of sight towards
G10.6-0.4 (W31C) cannot be accounted for by gas-phase chemical models. In this
paper we investigate the role of surface reactions on dust grains in diffuse
regions, and we find that formation of the hydrides by surface reactions on
dust grains with efficiency comparable to that for H$_2$ formation reconciles
models with observations of nitrogen hydrides. However, similar surface
reactions do not contribute significantly to the hydrides of O$^+$ ions
detected by Herschel/HIFI present along many sight lines in the Galaxy. The
O$^+$ hydrides can be accounted for by conventional gas-phase chemistry either
in diffuse clouds of very low density with normal cosmic ray fluxes or in
somewhat denser diffuse clouds with high cosmic ray fluxes. Hydride chemistry
in dense dark clouds appears to be dominated by gas-phase ion-molecule
reactions.


title:
Proper motions of 15 pulsars: a comparison between Bayesian and
  frequentist algorithms

abstract:
  We present proper motions for 15 pulsars which are observed regularly by the
Nanshan 25-m radio telescope. Two methods, the frequentist method (Coles et
al.2011) and the Bayesian (Lentati et al. 2014) method, are used and the
results are compared. We demonstrate that the two methods can be applied to
young pulsar data sets that exhibit large amounts of timing noise with steep
spectral exponents and give consistent results. The measured positions also
agree with very-long-baseline interferometric positions. Proper motions for
four pulsars are obtained for the first time, and improved values are obtained
for five pulsars.


title: Emergence of Persistent Infection due to Heterogeneity

abstract:
  We explore the emergence of persistent infection in a patch of population,
where the disease progression of the individuals is given by the SIRS model and
an individual becomes infected on contact with another infected individual. We
investigate the persistence of contagion qualitatively and quantitatively,
under varying degrees of heterogeneity in the initial population. We observe
that when the initial population is uniform, consisting of individuals at the
same stage of disease progression, infection arising from a contagious seed
does not persist. However when the initial population consists of randomly
distributed refractory and susceptible individuals, a single source of
infection can lead to sustained infection in the population, as heterogeneity
facilitates the de-synchronization of the phases in the disease cycle of the
individuals. We also show how the average size of the window of persistence of
infection depends on the degree of heterogeneity in the initial composition of
the population. In particular, we show that the infection eventually dies out
when the entire initial population is susceptible, while even a few
susceptibles among an heterogeneous refractory population gives rise to a large
persistent infected set.


title: Merging MCMC Subposteriors through Gaussian-Process Approximations

abstract:
  Markov chain Monte Carlo (MCMC) algorithms have become powerful tools for
Bayesian inference. However, they do not scale well to large-data problems.
Divide-and-conquer strategies, which split the data into batches and, for each
batch, run independent MCMC algorithms targeting the corresponding
subposterior, can spread the computational burden across a number of separate
workers. The challenge with such strategies is in recombining the subposteriors
to approximate the full posterior. By creating a Gaussian-process approximation
for each log-subposterior density we create a tractable approximation for the
full posterior. This approximation is exploited through three methodologies:
firstly a Hamiltonian Monte Carlo algorithm targeting the expectation of the
posterior density provides a sample from an approximation to the posterior;
secondly, evaluating the true posterior at the sampled points leads to an
importance sampler that, asymptotically, targets the true posterior
expectations; finally, an alternative importance sampler uses the full
Gaussian-process distribution of the approximation to the log-posterior density
to re-weight any initial sample and provide both an estimate of the posterior
expectation and a measure of the uncertainty in it.


title: Study of HERA data at Low Q^2 and Low x

abstract:
  In the HERAPDF2.0 PDF analysis it was noted that the fit $\chi^2$ worsens
significantly at low $Q^2$ for both NLO and NNLO fits. The turn over of the
reduced cross section at low-$x$ and low $Q^2$ due to the contribution of the
longitudinal cross section $F_L$ is also not very well described. In this paper
the prediction for $F_L$ is highlighted and the corresponding extraction of
$F_2$ from the data is further investigated, showing discrepancies with
description of HERAPDF2.0 at low $x$ and $Q^2$. The effect of adding a simple
higher twist term of the form ~$F_L*A/Q^2$ to the description of $F_L$ is
investigated. This results in a significantly better description of the reduced
cross-sections, $F_2$ and $F_L$ at low $x$, $Q^2$ and a significantly lower
$\chi^2$ for the NNLO fit as compared to the NLO fit. This is not the case if
the higher twist term is added to $F_2$


title:
Magnetic cycles of Sun-like stars with different levels of coronal and
  chromospheric activity -- comparison with the Sun

abstract:
  The atmospheric activity of the Sun and Sun-like stars is analyzed involving
observations from HK-project at the Mount Wilson Observatory, the California
and Carnegie Planet Search Program at the Keck and Lick Observatories and the
Magellan Planet Search Program at the Las Campanas Observatory. We show that
for stars of F, G and K spectral classes, the cyclic activity, similar to the
11-yr solar cycles, is different: it becomes more prominent in K-stars.
Comparative study of Sun-like stars with different levels of the chromospheric
and coronal activity confirms that the Sun belongs to stars with the low level
of the chromospheric activity and stands apart among these stars by the minimum
level of its coronal radiation and the minimum level of its variations of the
photospheric flux.


title:
Improved measurement of parton distribution functions and
  $\alpha_s(M_Z)$ with the LHeC

abstract:
  The potential of the LHeC, a future electron-proton collider, for precision
Deep Inelastic Scattering measurements is reviewed with particular emphasis on
the reduction of uncertainties on the parton distribution functions (PDFs) of
the proton and on the measurement of $\alpha_s(M_Z)$. The interpretation of
possible Beyond Standard Model (BSM) signals at the LHC is crucially dependent
on precise knowledge of the predictions of the Standard Model (SM) and the
uncertainties on PDFs and $\alpha_s(M_Z) $are a limiting factor. The LHeC
project, running in parallel with later stages of LHC running, would provide
much improved precision on the PDFs as compared to the precision expected from
LHC data alone.


title: On Haar systems for groupoids

abstract:
  It is shown that a locally compact groupoid with open range map does not
always admit a Haar system. It then is shown how to construct a Haar system if
the stability groupoid and the quotient by the stability groupoid both admit
one.


title: Pointwise multipliers of Orlicz function spaces and factorization

abstract:
  In the paper we find representation of the space of pointwise multipliers
between two Orlicz function spaces, which appears to be another Orlicz space
and the formula for the Young function generating this space is given. Further,
we apply this result to find necessary and suffcient conditions for
factorization of Orlicz function spaces.


title:
Detailed investigation of the phase transition in
  K$_{x}$P$_4$W$_{8}$O$_{32}$ and experimental arguments for a charge density
  wave due to hidden nesting

abstract:
  Detailed structural and magnetotransport properties of the monophosphate
tungsten bronze K$_{x}$P$_4$W$_{8}$O$_{32}$ single crystals are reported. Both
galvanomagnetic and thermal properties are shown to be consistent with a charge
density wave electronic transition due to hidden nesting of quasi - 1D portion
of the Fermi surface. We also observe the enhancement of electronic anisotropy
due to reconstruction of the Fermi surface at the Peierls transition. The
resistivity presents a thermal hysteresis suggesting a first order nature
characteristics of a strong coupling scenario. However, other measurements such
as the change of carriers density demonstrate a second order Peierls scenario
with weak coupling features. We suggest that the structural transition driven
by the residual strain in the K - P - O environment is responsible for the
resistivity hysteresis and modifes the Fermi surface which then helps the rise
to the second order Peierls instability.


title:
Optimal parameters identification and sensitivity study for Abrasive
  Waterjet Milling model

abstract:
  In this paper we present the work related to the parameters identification
for Abrasive Waterjet Milling (AWJM) model that appears as an ill-posed inverse
problem. The necessity of studying this problem comes from the industrial
milling applications where the possibility to predict and model the final
surface with high accuracy is one of the primary tasks in the absence of any
knowledge of the model parameters that should be used. The adjoint approach
based on corresponding Lagrangian gives the opportunity to find out the
unknowns of the AWJM model and their optimal values that could be used to
reproduce the required trench profile. Due to the complexity of the nonlinear
problem and the large number of the model parameters, we use an automatic
differentiation (AD) software tool. This approach also gives us the ability to
distribute the research on more complex cases and consider different types of
model errors and 3D time dependent model with variations of the jet feed speed.
This approach gives us a good opportunity to identify the optimal model
parameters and predict the surface profile both with self-generated data and
measurements obtained from the real production. Considering different types of
model errors allows us to receive the results acceptable in manufacturing and
to expect the proper identification of unknowns.


title: Aesthetical criterion in art and science

abstract:
  In the paper, the authors elaborate some recently published research
concerning the originality of artworks in terms of self-organization in the
complex systems physics. It has been demonstrated that the originality issue
such conceived leads to the criterion of a substantial aesthetics whose
applicability is not restricted to the fine arts domain only covering also
physics, biology, cosmology and other fields construed in the complex systems
terms. Moreover, it is about a truth criterion related to the traditional
personality conception revealing the ontological context transcendent to the
gnoseological dualism of subjective and objective reality that is
characteristic of modern science and humanities. Thus, it is considered to be
an aesthetical criterion substantiating art and science as well as the other
developments of the postmodern era. Its impact to psychology, education,
ecology, culture and other humanities is briefly indicated.


title:
Simultaneous analysis of matter radii, transition probabilities, and
  excitation energies of Mg isotopes by angular-momentum-projected
  configuration-mixing calculations

abstract:
  We perform simultaneous analysis of (1) matter radii, (2) $B(E2; 0^+
\rightarrow 2^+ )$ transition probabilities, and (3) excitation energies,
$E(2^+)$ and $E(4^+)$, for $^{24-40}$Mg by using the beyond mean-field (BMF)
framework with angular-momentum-projected configuration mixing with respect to
the axially symmetric $\beta_2$ deformation with infinitesimal cranking. The
BMF calculations successfully reproduce all of the data for $r_{\rm m}$,
$B(E2)$, and $E(2^+)$ and $E(4^+)$, indicating that it is quite useful for data
analysis, particularly for low-lying states. We also discuss the absolute value
of the deformation parameter $\beta_2$ deduced from measured values of $B(E2)$
and $r_{\rm m}$. This framework makes it possible to investigate the effects of
$\beta_2$ deformation, the change in $\beta_2$ due to restoration of rotational
symmetry, $\beta_2$ configuration mixing, and the inclusion of time-odd
components by infinitesimal cranking. Under the assumption of axial deformation
and parity conservation, we clarify which effect is important for each of the
three measurements, and propose the kinds of BMF calculations that are
practical for each of the three kinds of observables.


title:
Effect of Dzyaloshinski-Moriya interaction on spin-polarized neutron
  scattering

abstract:
  For magnetic materials containing many lattice imperfections (e.g.,
nanocrystalline magnets), the relativistic Dzyaloshinski-Moriya (DM)
interaction may result in nonuniform spin textures due to the lack of inversion
symmetry at interfaces. Within the framework of the continuum theory of
micromagnetics, we explore the impact of the DM interaction on the elastic
magnetic small-angle neutron scattering (SANS) cross section of bulk
ferromagnets. It is shown that the DM interaction gives rise to a
polarization-dependent asymmetric term in the spin-flip SANS cross section.
Analysis of this feature may provide a means to determine the DM constant.


title:
Simulations of Ion Velocity Distribution Functions Taking into Account
  Both Elastic and Charge Exchange Collisions

abstract:
  Based on accurate representation of the He+-He angular differential
scattering cross sections consisting of both elastic and charge exchange
collisions, we performed detailed numerical simulations of the ion velocity
distribution functions (IVDF) by Monte Carlo collision method (MCC). The
results of simulations are validated by comparison with the experimental data
of the ion mobility and the transverse diffusion. The IVDF simulation study
shows that due to significant effect of scattering in elastic collisions IVDF
cannot be separated into product of two independent IVDFs in the transverse and
parallel to the electric field directions.


title: Gravity duals of boundary cones

abstract:
  The replica trick defines Renyi entropies as partition functions on conically
singular geometries. We discuss their gravity duals: regular bulk solutions to
the Einstein equations inducing conically singular metrics at the boundary.
When the conical singularity is supported on a flat or spherical surface, these
solutions are rewritings of the hyperbolic black hole. For more general shapes,
these solutions are new. We construct them perturbatively in a double expansion
in the distance and strength of the conical singularity, and extract the vacuum
polarisation due to the cone. Recent results about the structure of logarithmic
divergences of Renyi entropies are reproduced ---in particular, $f_b\neq f_c$.
We discuss in detail the dynamical resolution of the singularity in the bulk.
This resolution is in agreement with a previous proposal, and indicates a
non-minimal settling to the `splitting problem': an apparent ambiguity in the
holographic entropy formula of certain theories with higher derivatives.


title: Spectral analysis of the Dirac operator on a 3-sphere

abstract:
  We study the (massless) Dirac operator on a 3-sphere equipped with Riemannian
metric. For the standard metric the spectrum is known. In particular, the
eigenvalues closest to zero are the two double eigenvalues +3/2 and -3/2. Our
aim is to analyse the behaviour of eigenvalues when the metric is perturbed in
an arbitrary smooth fashion from the standard one. We derive explicit
perturbation formulae for the two eigenvalues closest to zero, taking account
of the second variations. Note that these eigenvalues remain double eigenvalues
under perturbations of the metric: they cannot split because of a particular
symmetry of the Dirac operator in dimension three (it commutes with the
antilinear operator of charge conjugation). Our perturbation formulae show that
in the first approximation our two eigenvalues maintain symmetry about zero and
are completely determined by the increment of Riemannian volume. Spectral
asymmetry is observed only in the second approximation of the perturbation
process. As an example we consider a special family of metrics, the so-called
generalized Berger spheres, for which the eigenvalues can be evaluated
explicitly.


title:
Systems Aliasing in Dynamic Network Reconstruction: Issues on Low
  Sampling Frequencies

abstract:
  Network reconstruction of dynamical continuous-time (CT) systems is motivated
by applications in many fields. Due to experimental limitations, especially in
biology, data could be sampled at low frequencies, leading to significant
challenges in network inference. We introduce the concept of "system aliasing"
and characterize the minimal sampling frequency that allows reconstruction of
CT systems from low sampled data. A test criterion is also proposed to check
whether system aliasing is presented. With no system aliasing, the paper
provides an algorithm to reconstruct dynamic network from data in the presence
of noise. In addition, when there is system aliasing we perform studies that
add additional prior information of the system such as sparsity. This paper
opens new directions in modelling of network systems where samples have
significant costs. Such tools are essential to process the available data in
applications subject to current experimental limitations.


title: Generalized Matsumoto-Tits sections and quantum quasi-shuffle algebras

abstract:
  In this paper generalized Matsumoto-Tits sections lifting permutations to the
algebra associated to a generalized virtual braid monoid are defined. They are
then applied to study the defining relations of the quantum quasi-shuffle
algebras via the total symmetrization operator.


title:
An extension of Furstenberg's structure theorem for Noetherian modules
  and multiple recurrence theorems I

abstract:
  We extend Furstenberg's structure theorem to any standard Borel $G$-space,
where $G$ is any locally compact second countable Noetherian module over a
syndetic ring.


title: The Cuntz-Pimsner extension and mapping cone exact sequences

abstract:
  For Cuntz-Pimsner algebras of bi-Hilbertian bimodules of finite
Jones-Watatani index satisfying some side conditions, we give an explicit
isomorphism between the $K$-theory exact sequences of the mapping cone of the
inclusion of the coefficient algebra into a Cuntz-Pimsner algebra, and the
Cuntz-Pimsner exact sequence. In the process we extend some results by the
second author and collaborators from finite projective bimodules to finite
index bimodules, and also clarify some aspects of Pimsner's `extension of
scalars' construction.


title:
Multifractal analysis for the occupation measure of stable-like
  processes

abstract:
  In this article, we investigate the local behaviors of the occupation measure
$\mu$ of a class of real-valued Markov processes M, defined via a SDE. This
(random) measure describes the time spent in each set A $\subset$ R by the
sample paths of M. We compute the multifractal spectrum of $\mu$, which turns
out to be random, depending on the trajec-tory. This remarkable property is in
sharp contrast with the results previously obtained on occupation measures of
other processes (such as L{\'e}vy processes), since the multifractal spectrum
is usually determinis-tic, almost surely. In addition, the shape of this
multifractal spectrum is very original, reflecting the richness and variety of
the local behaviors. The proof is based on new methods, which lead for instance
to fine estimates on Hausdorff dimensions of certain jump configurations in
Poisson point processes.


title:
An extension of Furstenberg's structure theorem for Noetherian modules
  and multiple recurrence theorems II

abstract:
  Using a recent Furstenberg structure theorem, we obtain a quantitative
multiple recurrence theorem relative to any locally compact second countable
Noetherian module over a syndetic ring.


title: One-step theory of two-photon photoemission

abstract:
  A theoretical frame for two-photon photoemission is derived from the general
theory of pump-probe photoemission, assuming that not only the probe but also
the pump pulse is sufficiently weak. This allows us to use a perturbative
approach to compute the lesser Green function within the Keldysh formalism.
Two-photon photoemission spectroscopy is a widely used analytical tool to study
non-equilibrium phenomena in solid materials. Our theoretical approach aims at
a material-specific, realistic and quantitative description of the
time-dependent spectrum based on a picture of effectively independent electrons
as described by the local-density approximation in band-structure theory. To
this end we follow Pendry's one-step theory of the photoemission process as
close as possible and heavily make use of concepts of multiple-scattering
theory, such as the representation of the final state by a time-reversed
low-energy electron diffraction state. The formalism is fully relativistic and
allows for a quantitative calculation of the time-dependent photocurrent for
moderately correlated systems like simple metals or more complex compounds like
topological insulators. An application to the Ag(100) surface is discussed in
detail.


title: Analytic combinatorics of connected graphs

abstract:
  We enumerate the connected graphs that contain a number of edges growing
linearly with respect to the number of vertices. So far, only the first term of
the asymptotics and a bound on the error were known. Using analytic
combinatorics, ie generating function manipulations, we derive a formula for
the coefficients of the complete asymptotic expansion. The same result is
derived for connected multigraphs.


title:
The Effect of Tetrahedral versus Octahedral Network-Blocking Atom
  Substitutions on Lithium Ion Conduction in LLZO Garnet

abstract:
  Molecular dynamics calculations are carried out on pure, Al-substituted, and
In-substituted LLZO. The calculations show that the tendency of Al to occupy
the 24d sites in LLZO lithium ion conductors is hypothesized here to negatively
impact ionic conductivity. The room-temperature ionic conductivity of In-LLZO,
in which the In resides at the 48g sites, is predicted to be an order of
magnitude higher than Al-LLZO. Consideration of the simple tetrahedral topology
of the lithium ion conduction network suggests that the increased conductivity
arises because the 48g site sits at a bridge in the lithium ion conduction
network. An immobile ion residing in this location blocks fewer lithium
conduction pathways than an ion, such as Al, that preferentially occupies the
24d site located at a node within the network. In addition, the electronic
structure calculations presented here indicate no large difference in the
stabilities of tetragonal and cubic phases for the aluminum-substituted and
indium-substituted compounds. In both cases, the cubic phase is more stable
than the tetragonal phase. This indicates that it should be possible to make a
cubic In-LLZO phase with significant conductivity enhancement over the cubic
Al-LLZO phase.


title:
An extension of Furstenberg's structure theorem for Noetherian modules
  and multiple recurrence theorems III

abstract:
  Using a recent Furstenberg structure theorem, we obtain Multiple Recurrence
Theorems relative to any locally compact second countable Noetherian module $G$
over a syndetic ring $R$, which generalizes Furstenberg's multiple recurrence
theorem. In addition we study the multiple Birkhoff center and the pointwise
multiple recurrence of a topological $G$-action on a compact metric space.


title: The spatial Rokhlin property for actions of compact quantum groups

abstract:
  We introduce the spatial Rokhlin property for actions of coexact compact
quantum groups on $\mathrm{C}^*$-algebras, generalizing the Rokhlin property
for both actions of classical compact groups and finite quantum groups. Two key
ingredients in our approach are the concept of sequentially split
$*$-homomorphisms, and the use of braided tensor products instead of ordinary
tensor products.
  We show that various structure results carry over from the classical theory
to this more general setting. In particular, we show that a number of
$\mathrm{C}^*$-algebraic properties relevant to the classification program pass
from the underlying $\mathrm{C}^*$-algebra of a Rokhlin action to both the
crossed product and the fixed point algebra. Towards establishing a
classification theory, we show that Rokhlin actions exhibit a rigidity property
with respect to approximate unitary equivalence. Regarding duality theory, we
introduce the notion of spatial approximate representability for actions of
discrete quantum groups. The spatial Rokhlin property for actions of a coexact
compact quantum group is shown to be dual to spatial approximate
representability for actions of its dual discrete quantum group, and vice
versa.


title: Action-based Dynamical Modelling for the Milky Way Disk

abstract:
  We present RoadMapping, a full-likelihood dynamical modelling machinery that
aims to recover the Milky Way's (MW) gravitational potential from large samples
of stars in the Galactic disk. RoadMapping models the observed positions and
velocities of stars with a parametrized, three-integral distribution function
(DF) in a parametrized axisymmetric potential. We investigate through
differential test cases with idealized mock data how the breakdown of model
assumptions and data properties affect constraints on the potential and DF. Our
key results are: (i) If the MW's true potential is not included in the assumed
model potential family, we can - in the axisymmetric case - still find a robust
estimate for the potential, with only <~ 10% difference in surface density
within |z| <= 1.1 kpc inside the observed volume. (ii) Modest systematic
differences between the true and model DF are inconsequential. E.g, when
binning stars to define sub-populations with simple DFs, binning errors do not
affect the modelling as long as the DF parameters of neighbouring bins differ
by < 20%. In addition, RoadMapping ensures unbiased potential estimates for
either (iii) small misjudgements of the spatial selection function (i.e., <~
15% at the survey volume's edge), (iv) if distances are known to within 10%, or
(v) if proper motion uncertainties are known within 10% or are smaller than
delta mu <~ 1 mas/yr. Challenges are the rapidly increasing computational costs
for large sample sizes. Overall, RoadMapping is well suited to making precise
new measurements of the MW's potential with data from the upcoming Gaia
releases.


title:
Modeling and simulation of coagulation according to DLVO-theory in a
  continuum model for electrolyte solutions

abstract:
  This paper presents a model of coagulation in electrolyte solutions. In this
paper, the coagulation process is modeled according to DLVO-theory, which is an
atomistic theory. On the other hand, we describe the dynamics in the
electrolyte solutions by the Poisson-Nernst-Planck system, which is a continuum
model. The contribution of this paper is to include the atomistic description
of coagulation based on DLVO-theory in the continuum Poisson-Nernst-Planck
system. Thereby, we involve information from different spatial scales. For this
reason, the presented model accounts for the short-range interactions and the
long-range interactions, which drive the coagulation process. Furthermore,
many-body effects are naturally included as the resulting model is a continuum
model.


title: Behaviour of the Brascamp--Lieb constant

abstract:
  Recent progress in multilinear harmonic analysis naturally raises questions
about the local behaviour of the best constant (or bound) in the general
Brascamp--Lieb inequality as a function of the underlying linear
transformations. In this paper we prove that this constant is continuous, but
is not in general differentiable.


title: Condensed Matter Laboratory: new application for quantum simulation

abstract:
  The purpose of this paper is to introduce Condensed-Matter-Laboratory (CML)
application for simulating solids and nanostructures and calculating different
properties of them by density functional theory and using Green's function
theory in tight-binding approximation to calculate phononic and spin dependent
or independent electronic properties of different systems. Also, it can be used
for calculating thermodynamic properties of solids and nanostructures using
statistical mechanics. The CML is a cross-platform application with a graphical
user interface design that is user-friendly and easy to work with. This
application is written in c++ and fortran and has parallel processing ability.
To show flexibility of this application some reasons are presented.


title: Percolation of random nodal lines

abstract:
  We prove a Russo-Seymour-Welsch percolation theorem for nodal domains and
nodal lines associated to a natural infinite dimensional space of real analytic
functions on the real plane. More precisely, let $U$ be a smooth connected
bounded open set in $\mathbb R^2$ and $\gamma, \gamma'$ two disjoint arcs of
positive length in the boundary of $U$. We prove that there exists a positive
constant $c$, such that for any positive scale $s$, with probability at least
$c$ there exists a connected component of $\{x\in \bar U, \, f(sx)
\textgreater{} 0\} $ intersecting both $\gamma$ and $\gamma'$, where $f$ is a
random analytic function in the Wiener space associated to the real
Bargmann-Fock space. For $s$ large enough, the same conclusion holds for the
zero set $\{x\in \bar U, \, f(sx) = 0\} $. As an important intermediate result,
we prove that sign percolation for a general stationary Gaussian field can be
made equivalent to a correlated percolation model on a lattice.


title: Wehrl entropies and Euclidean Landau levels

abstract:
  We are concerned with an information-theoretic measure of uncertainty for
quantum systems. Precisely, the Wehrl entropy of the phase-space probability
$Q^{(m)}_{\hat{\rho}}=\left\langle z,m|\hat{\rho}|z,m\right\rangle $ which is
known as Husimi function, where $\hat{\rho}$ is a density operator and $%
\left|z,m\right\rangle $ are coherent states attached to an Euclidean $m$th
Landau level. We obtain the Husimi function $Q^{(m)}_{\beta}$ of the thermal
density operator $\hat{\rho}_{\beta}$ of the harmonic oscillator, which leads
by duality, to the Laguerre probability distribution of the mixed light. We
discuss some basic properties of $Q^{(m)}_{\beta}$ such as its characteristic
function and its limiting logarithmic moment generating function from which we
derive the rate function of the sequence of probability distributions
$Q^{(m)}_{\beta},\ m=0,1,2,...$. For $m\geq1$, we establish an exact expression
for the Wehrl entropy of the density operator $% \hat{\rho}_{\beta}$ and we
discuss the behavior of this entropy with respect to the temperature parameter
$T=1/\beta$


title: Search for the sterile neutrino mixing with the ICAL detector at INO

abstract:
  The study has been carried out on the prospects of probing the sterile
neutrino mixing with the magnetized Iron CALorimeter (ICAL) at the India-based
Neutrino Observatory (INO), using atmospheric neutrinos as a source. The
so-called 3~$+$~1 scenario is considered for active-sterile neutrino mixing and
lead to projected exclusion curves in the sterile neutrino mass and mixing
angle plane. The analysis is performed using the neutrino event generator
NUANCE, modified for ICAL, and folded with the detector resolutions obtained by
the INO collaboration from a full GEANT4 based detector simulation. A
comparison has been made between the results obtained from the analysis
considering only the energy and zenith angle of the muon and combined with the
hadron energy due to the neutrino induced event. A small improvement has been
observed with the addition of the hadron information to the muon. In the
analysis we consider neutrinos coming from all zenith angles and the Earth
matter effects are also included. The inclusion of events from all zenith
angles improves the sensitivity to sterile neutrino mixing by about 35$\%$ over
the result obtained using only down-going events. The improvement mainly stems
from the impact of Earth matter effects on active-sterile mixing. The expected
precision of ICAL on the active-sterile mixing is explored and allowed
confidence level (C.L.) contours presented. At the assumed true value of
$10^\circ$ for the sterile mixing angles and marginalization over $\Delta
m^2_{41}$ and the sterile mixing angles, the upper bound at 90\% C.L. (from 2
parameter plots) is around $20^\circ$ for $\theta_{14}$ and $\theta_{34}$, and
about $12^\circ$ for $\theta_{24}$.


title: On Free Field Realizations of $W(2,2)$-Modules

abstract:
  The aim of the paper is to study modules for the twisted Heisenberg-Virasoro
algebra $\mathcal H$ at level zero as modules for the $W(2,2)$-algebra by using
construction from [J. Pure Appl. Algebra 219 (2015), 4322-4342,
arXiv:1405.1707]. We prove that the irreducible highest weight ${\mathcal
H}$-module is irreducible as $W(2,2)$-module if and only if it has a typical
highest weight. Finally, we construct a screening operator acting on the
Heisenberg-Virasoro vertex algebra whose kernel is exactly $W(2,2)$ vertex
algebra.


title:
Uncovering the non-equilibrium phase structure of an open quantum spin
  system

abstract:
  We experimentally and theoretically investigate the non-equilibrium phase
structure of a well-controlled driven-disspative quantum spin system governed
by the interplay of coherent driving, spontaneous decay and long-range
spin-spin interactions. We discover that the rate of population loss provides a
convenient macroscopic observable that exhibits power-law scaling with the
driving strength over several orders of magnitude. The measured scaling
exponents reflect the underlying non-equilibrium phase structure of the
many-body system, which includes dissipation-dominated, paramagnetic and
critical regimes as well as an instability which drives the system towards
states with high excitation density. This opens up a new means to study and
classify quantum systems out of equilibrium and extends the domain where
scale-invariant behavior may be found in nature.


title: Tuning optical properties of Ge nanocrystals by Si shell

abstract:
  We present a theoretical study of Ge-core/Si-shell nanocrystals in a wide
bandgap matrix and compare the results with experimental data obtained from the
samples prepared by co-sputtering. The empirical tight-binding technique allows
us to account for the electronic structure under strain on the atomistic level.
We find that a Si shell as thick as 1 monolayer is enough to reduce the
radiative recombination rate as a result of valley $L - X$ cross-over. Thin Si
shell leads to a dramatic reduction of the optical bandgap from visible to
near-infrared range, which is promising for photovoltaics and photodetector
applications. Our detailed analysis of the structure of the confined electron
and hole states in real and reciprocal spaces indicates that the type-II
heterostructure is not yet achieved for Si shells with the thickness below 0.8
nm, despite some earlier theoretical predictions. The energy levels of holes
are affected by the Si shell stronger than the electron states, even though
holes are completely confined to the Ge core. This occurs probably due to a
strong influence of strain on the band offsets.


title:
Role of Entropy and Structural Parameters in the Spin State Transition
  of LaCoO$_3$

abstract:
  The spin state transition in LaCoO$_3$ has eluded description for decades
despite concerted theoretical and experimental effort. In this study, we
approach this problem using fully charge self-consistent Density Functional
Theory + Embedded Dynamical Mean Field Theory (DFT+DMFT). We show from first
principles that LaCoO$_3$ cannot be described by a single, pure spin state at
any temperature. Instead, we observe a gradual change in the population of
higher spin multiplets with increasing temperature, with the high spin
multiplets being excited at the onset of the spin state transition followed by
the intermediate spin multiplets being excited at the metal insulator
transition temperature. We explicitly elucidate the critical role of lattice
expansion and oxygen octahedral rotations in the spin state transition. We also
reproduce, from first principles, that the spin state transition and the
metal-insulator transition in LaCoO$_3$ occur at different temperature scales.
In addition, our results shed light on the importance of electronic entropy in
driving the spin state transition, which has so far been ignored in all first
principles studies of this material.


title:
Experiment-friendly kinetic analysis of single molecule data in and out
  of equilibrium

abstract:
  We present a simple and robust technique to extract kinetic rate models and
thermodynamic quantities from single molecule time traces. SMACKS (Single
Molecule Analysis of Complex Kinetic Sequences) is a maximum likelihood
approach that works equally well for long trajectories as for a set of short
ones. It resolves all statistically relevant rates and also their
uncertainties. This is achieved by optimizing one global kinetic model based on
the complete dataset, while allowing for experimental variations between
individual trajectories. In particular, neither a priori models nor equilibrium
have to be assumed. The power of SMACKS is demonstrated on the kinetics of the
multi-domain protein Hsp90 measured by smFRET (single molecule F\"orster
resonance energy transfer). Experiments in and out of equilibrium are analyzed
and compared to simulations, shedding new light on the role of Hsp90's ATPase
function. SMACKS pushes the boundaries of single molecule kinetics far beyond
current methods.


title: Quantum decoration transformation for spin models

abstract:
  It is quite relevant the extension of decoration transformation for quantum
spin models since most of the real materials could be well described by
Heisenberg type models. Here we propose an exact quantum decoration
transformation and also showing interesting properties such as the persistence
of symmetry and the symmetry breaking during this transformation. Although the
proposed transformation, in principle, cannot be used to map exactly a quantum
spin lattice model into another quantum spin lattice model, since the operators
are non-commutative. However, it is possible the mapping in the "classical"
limit, establishing an equivalence between both quantum spin lattice models. To
study the validity of this approach for quantum spin lattice model, we use the
Zassenhaus formula, and we verify how the correction could influence the
decoration transformation. But this correction could be useless to improve the
quantum decoration transformation because it involves the
second-nearest-neighbor and further nearest neighbor couplings, which leads
into a cumbersome task to establish the equivalence between both lattice
models. This correction also gives us valuable information about its
contribution, for most of the Heisenberg type models, this correction could be
irrelevant at least up to the third order term of Zassenhaus formula. This
transformation is applied to a finite size Heisenberg chain, comparing with the
exact numerical results, our result is consistent for weak xy-anisotropy
coupling. We also apply to bond-alternating Ising-Heisenberg chain model,
obtaining an accurate result in the limit of the quasi-Ising chain.

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


title: Anderson localisation of visible light on a nanophotonic chip

abstract:
  We demonstrate Anderson localisation of visible light on a chip and report
quality factors exceeding highly engineered two-dimensional cavities. Our
results reverse the trend, observed so far, of the quality of disorder-induced
light confinement being orders of magnitude lower than engineered devices.
Furthermore, by implementing a sensitive imaging technique, we directly
visualise the localised modes, determine their position on the device and
measure their spatial extension. Our findings prove the potential of
disorder-induced localised light for scalable, room temperature, optical
devices, operating in the visible range of wavelengths.


title: On Superalgebras of Matrices with Symmetry Properties

abstract:
  It is known that semi-magic square matrices form a 2-graded algebra or
superalgebra with the even and odd subspaces under centre-point reflection
symmetry as the two components. We show that other symmetries which have been
studied for square matrices give rise to similar superalgebra structures,
pointing to novel symmetry types in their complementary parts. In particular,
this provides a unifying framework for the composite `most perfect square'
symmetry and the related class of `reversible squares'; moreover, the
semi-magic square algebra is identified as part of a 2-gradation of the general
square matrix algebra. We derive explicit representation formulae for matrices
of all symmetry types considered, which can be used to construct all such
matrices.


title: Maximum-expectation matching under recourse

abstract:
  This paper addresses the problem of maximizing the expected size of a
matching in the case of unreliable vertices and/or edges. The assumption is
that upon failure, remaining vertices that have not been matched may be subject
to a new assignment. This process may be repeated a given number of times, and
the objective is to end with the overall maximum number of matched vertices.
  The origin of this problem is in kidney exchange programs, going on in
several countries, where a vertex is an incompatible patient-donor pair; the
objective is to match these pairs so as to maximize the number of served
patients. A new scheme is proposed for matching rearrangement in case of
failure, along with a prototype algorithm for computing the optimal expectation
for the number of matched vertices.
  Computational experiments reveal the relevance and limitations of the
algorithm, in general terms and for the kidney exchange application.


title: Categorical Quantum Mechanics II: Classical-Quantum Interaction

abstract:
  This is the second part of a three-part overview, in which we derive the
category-theoretic backbone of quantum theory from a process ontology, treating
quantum theory as a theory of systems, processes and their interactions. In
this part we focus on classical-quantum interaction.
  Classical and quantum systems are treated as distinct types, of which the
respective behavioural properties are specified in terms of processes and their
compositions. In particular, classicality is witnessed by 'spiders' which fuse
together whenever they connect. We define mixedness and show that pure
processes are extremal in the space of all processes, and we define
entanglement and show that quantum theory indeed exhibits entanglement. We
discuss the classification of tripartite qubit entanglement and show that both
the GHZ-state and the W-state come from spider-like families of processes,
which differ only in how they behave when they are connected by two or more
wires. We define measurements and provide fully-comprehensive descriptions of
several quantum protocols involving classical data flow. Finally, we give a
notion of 'genuine quantumness', from which special processes called 'phase
spiders' arise, and get a first glimpse of quantum non-locality.


title:
Variational Bayesian Inference for Hidden Markov Models With
  Multivariate Gaussian Output Distributions

abstract:
  Hidden Markov Models (HMM) have been used for several years in many time
series analysis or pattern recognitions tasks. HMM are often trained by means
of the Baum-Welch algorithm which can be seen as a special variant of an
expectation maximization (EM) algorithm. Second-order training techniques such
as Variational Bayesian Inference (VI) for probabilistic models regard the
parameters of the probabilistic models as random variables and define
distributions over these distribution parameters, hence the name of this
technique. VI can also bee regarded as a special case of an EM algorithm. In
this article, we bring both together and train HMM with multivariate Gaussian
output distributions with VI. The article defines the new training technique
for HMM. An evaluation based on some case studies and a comparison to related
approaches is part of our ongoing work.


title:
Statistical and Thermodynamical Studies of the Strongly Interacting
  Matter

abstract:
  In this thesis we discuss three separate analysis of various phenomenological
aspects of heavy-ion collisions (HIC). The first one is a possible
generalization of the kinetic theory framework for dense systems. We
investigate its long-time behaviour and the properties of the equilibrium. The
second discussion is about the phenomenological analysis of the azimuthal
asymmetry of the particle yields in a HIC, where we link the initial stage
geometrical asymmetry to the particle yields and examine the possible
organizing mechanisms that could be responsible for such a relation. The third,
and also the most thorough part of the thesis is about the relation of the
spectral density of quasi-particle states and the macroscopic fluidity measure
(the ratio of shear viscosity and the entropy density) and other transport
properties of the system. We extensively study the liquid-gas crossover with
the help of model spectral functions. The main conclusion is that the relative
intensification of the continuum of the scattering states compared to the
quasi-particle peak makes the matter more fluent.


title: Near-infrared photometry of WISE J085510.74$-$071442.5

abstract:
  (Abridged) We aim at measuring the near-infrared photometry, and deriving the
mass, age, temperature, and surface gravity of WISE J085510.74-071442.5
(J0855-0714), which is the coolest known object beyond the Solar System as of
today. We use publicly available data from the archives of the HST and the VLT
to determine the emission of this source at 1.153 micron (F110W) and 1.575
micron (CH_4). J0855-0714 is detected at both wavelengths with signal-to-noise
ratio of ~10 (F110W) and ~4 (CH_4-off) at the peak of the corresponding PSFs.
This is the first detection of J0855-0714 in the H-band. We measure 26.31 +/-
0.10 and 23.22 +/- 0.35 mag in F110W and CH_4 (Vega system). J0855-0714 remains
unresolved in the HST images that have a spatial resolution of 0.22".
Companions at separations of 0.5 AU (similar brightness) and at ~1 AU (~1 mag
fainter in the F110W filter) are discarded. By combining the new data with
published photometry, we build the spectral energy distribution of J0855-0714
from 0.89 to 22.09 micron, and contrast it against state-of-the-art
solar-metallicity models of planetary atmospheres. We determine a temperature
of 225-250 K, a bolometric luminosity of log L/Lsol = -8.57, and a high surface
gravity of log g = 5.0 (cm/s2), which suggests an old age although such a high
gravity is not fully compatible with evolutionary models. After comparison with
the cooling theory for brown dwarfs and planets, we infer a mass in the
interval 2-10 Mjup for ages of 1-12 Gyr and log g > 3.5 (cm/s2). At the age of
the Sun, J0855-0714 would be a ~5-Mjup free-floating planetary-mass object.
J0855-0714 may represent the old image of the free-floating planetary-mass
objects of similar mass discovered in star-forming regions and young stellar
clusters. As many J0855-0714-like objects as M5-L2 stars may be expected to
populate the solar neighborhood.


title:
The super-Virasoro singular vectors and Jack superpolynomials
  relationship revisited

abstract:
  A recent novel derivation of the representation of Virasoro singular vectors
in terms of Jack polynomials is extended to the supersymmetric case. The
resulting expression of a generic super-Virasoro singular vector is given in
terms of a simple differential operator (whose form is characteristic of the
sector, Neveu-Schwarz or Ramond) acting on a Jack superpolynomial. The latter
is indexed by a superpartition depending upon the two integers r,s that specify
the reducible module under consideration. The corresponding singular vector (at
grade rs/2), when expanded as a linear combination of Jack superpolynomials,
results in an expression that (in addition to being proved) turns out to be
more compact than those that have been previously conjectured. As an aside, in
relation with the differential operator alluded to above, a remarkable property
of the Jack superpolynomials at alpha=-3 is pointed out.


title:
Bright-dark vector soliton solutions for the coupled complex short pulse
  equations in nonlinear optics

abstract:
  Under investigation in this paper are the coupled complex short pulse
equations, which describe the propagation of ultra-short optical pulses in
cubic nonlinear media.Through the Hirota method, bright-dark one- and
two-soliton solutions are obtained. Interactions between two bright or two dark
solitons are verified to be elastic through the asymptotic analysis. With
different parameter conditions of the vector bright-dark two solitons, the
oblique interactions, bound states of solitons and parallel solitons are
analyzed.


title: On the maximum Lyapunov exponent of the motion in a chaotic layer

abstract:
  The maximum Lyapunov exponent (referred to the mean half-period of phase
libration) of the motion in the chaotic layer of a nonlinear resonance subject
to symmetric periodic perturbation, in the limit of infinitely high frequency
of the perturbation, has been numerically estimated by two independent methods.
The newly derived value of this constant is 0.80, with precision presumably
better than 0.01.


title: Measurement Protocol for the Entanglement Spectrum of Cold Atoms

abstract:
  Entanglement, and, in particular the entanglement spectrum, plays a major
role in characterizing many-body quantum systems. While there has been a surge
of theoretical works on the subject, no experimental measurement has been
performed to date because of the lack of an implementable measurement scheme.
Here, we propose a measurement protocol to access the entanglement spectrum of
many-body states in experiments with cold atoms in optical lattices. Our scheme
effectively performs a Ramsey spectroscopy of the entanglement Hamiltonian and
is based on the ability to produce several copies of the state under
investigation together with the possibility to perform a global swap gate
between two copies conditioned on the state of an auxiliary qubit. We show how
the required conditional swap gate can be implemented with cold atoms, either
by using Rydberg interactions or coupling the atoms to a cavity mode. We
illustrate these ideas on a simple (extended) Bose-Hubbard model where such a
measurement protocol reveals topological features of the Haldane phase.


title: Phase transition in a double branching annihilating random walk

abstract:
  This paper investigates the long-time behavior of double branching
annihilating random walkers with nearest-neighbor dependent rates. The system
consists of even number of particles which can execute nearest-neighbor random
walk and they can as well give birth in a parity conserving manner to two other
particles with rates $1$ and $b$, respectively, until they meet. Upon meeting,
each of the adjacent particles can branch with rate $p\cdot b$ while it can
annihilate, i.e. hop on, the other particle with rate $p$ for some $0< p\leq
1$. This process first appeared in the article by D. ben Avraham, F. Leyvraz
and S. Redner (Propagation and extinction in branching annihilating random
walks, Phys. Rev. E 50(3), 1994) and can be considered as the extension of
Sudbury's model (The branching annihilating process: an interacting particle
system, Ann. Probab., 18(2), 1990). We prove that in some region of the
parameters $(p,b)$, the process survives with positive probability. Combining
with Sudbury's extinction result it shows a phase transition phenomenon for
this model. In some sense our result also shows the sharpness of the
assumptions of the article by M. Bal\'azs and A. L. Nagy (Dependent double
branching annihilating random walk, Electron. J. Probab., 20(84), 2015). We use
similar arguments that was developed by M. Bramson and L. Gray in their article
titled "The survival of branching annihilating random walk" (Z. Wahrsch. Verw.
Gebiete, 68(4), 1985).


title:
Light-by-light scattering in ultraperipheral heavy-ion collisions at the
  LHC

abstract:
  We present cross sections for diphoton production in (semi)exclusive $PbPb$
collisions, relevant for the LHC. The calculation is based on equivalent photon
approximation in the impact parameter space. The cross sections for elementary
elastic scattering $\gamma \gamma \to \gamma \gamma$ subprocess are calculated
including two mechanisms: box diagrams with leptons and quarks in the loops and
a mechanism based on vector-meson dominance (VDM-Regge) model with virtual
intermediate vector-like excitations of the photons. We get measureable cross
sections in $PbPb$ collisions. We present many interesting differential
distributions which could be measured by the ALICE, CMS or ATLAS Collaborations
at the LHC. We study whether a separation of box and VDM-Regge contributions is
possible. We find that the cross section for elastic $\gamma \gamma$ scattering
could be measured in the heavy-ion collisions for subprocess energies smaller
than $W_{\gamma\gamma} \approx 15-20$~GeV.


title: Epireflective subcategories and formal closure operators

abstract:
  On a category $\mathscr{C}$ with a designated (well-behaved) class
$\mathcal{M}$ of monomorphisms, a closure operator in the sense of D. Dikranjan
and E. Giuli is a pointed endofunctor of $\mathcal{M}$, seen as a full
subcategory of the arrow-category $\mathscr{C}^\mathbf{2}$ whose objects are
morphisms from the class $\mathcal{M}$, which "commutes" with the codomain
functor $\mathsf{cod}\colon \mathcal{M}\to \mathscr{C}$. In other words, a
closure operator consists of a functor $C\colon \mathcal{M}\to\mathcal{M}$ and
a natural transformation $c\colon 1_\mathcal{M}\to C$ such that $\mathsf{cod}
\cdot C=C$ and $\mathsf{cod}\cdot c=1_\mathsf{cod}$. In this paper we adapt
this notion to the domain functor $\mathsf{dom}\colon
\mathcal{E}\to\mathscr{C}$, where $\mathcal{E}$ is a class of epimorphisms in
$\mathscr{C}$, and show that such closure operators can be used to classify
$\mathcal{E}$-epireflective subcategories of $\mathscr{C}$, provided
$\mathcal{E}$ is closed under composition and contains isomorphisms.
Specializing to the case when $\mathcal{E}$ is the class of regular
epimorphisms in a regular category, we obtain known characterizations of
regular-epireflective subcategories of general and various special types of
regular categories, appearing in the works of the second author and his
coauthors. These results show the interest in investigating further the notion
of a closure operator relative to a general functor. They also point out new
links between epireflective subcategories arising in algebra, the theory of
fibrations, and the theory of categorical closure operators.


title: The NIKA2 commissioning campaign: performance and first results

abstract:
  The New IRAM KID Array 2 (NIKA 2) is a dual-band camera operating with three
frequency-multiplexed kilopixels arrays of Lumped Element Kinetic Inductance
Detectors (LEKID) cooled at 150 mK. NIKA 2 is designed to observe the intensity
and polarisation of the sky at 1.15 and 2.0 mm wavelength from the IRAM 30 m
telescope. The NIKA 2 instrument represents a huge step in performance as
compared to the NIKA pathfinder instrument, which has already shown
state-of-the-art detector and photometric performance. After the commissioning
planned to be accomplished at the end of 2016, NIKA 2 will be an IRAM resident
instrument for the next ten years or more. NIKA 2 should allow the
astrophysical community to tackle a large number of open questions reaching
from the role of the Galactic magnetic field in star formation to the
discrepancy between cluster-based and CMB-based cosmology possibly induced by
the unknown cluster physics. We present an overview of the commissioning phase
together with some first results.


title:
On Block Representations and Spectral Properties of Semimagic Square
  Matrices

abstract:
  Using the decomposition of semimagic squares into the associated and balanced
symmetry types as a motivation, we introduce an equivalent representation in
terms of block-structured matrices. This block representation provides a way of
constructing such matrices with further symmetries and of studying their
algebraic behaviour, significantly advancing and contributing to the
understanding of these symmetry properties. In addition to studying classical
attributes, such as dihedral equivalence and the spectral properties of these
matrices, we show that the inherent structure of the block representation
facilitates the definition of low-rank semimagic square matrices. This is
achieved by means of tensor product blocks. Furthermore, we study the rank and
eigenvector decomposition of these matrices, enabling the construction of a
corresponding two-sided eigenvector matrix in rational terms of their entries.
The paper concludes with the derivation of a correspondence between the tensor
product block representations and quadratic form expressions of Gaussian type.


title:
Explicit constructions of optimal-access MDS codes with nearly optimal
  sub-packetization

abstract:
  An $(n,k,l)$ MDS array code of length $n,$ dimension $k=n-r$ and
sub-packetization $l$ is formed of $l\times n$ matrices over a finite field
$F,$ with every column of the matrix stored on a separate node in a distributed
storage system and viewed as a coordinate of the codeword. Repair of a failed
node can be performed by accessing a set of $d\le n-1$ helper nodes. The code
is said to have the optimal access property if the amount of data accessed at
each of the helper nodes meets a lower bound on this quantity. For
optimal-access MDS codes with $d=n-1,$ the sub-packetization $l$ satisfies the
bound $l\ge r^{(k-1)/r}.$ In our previous work, for any $n$ and $r,$ we
presented an explicit construction of optimal-access MDS codes with
sub-packetization $l=r^{n-1}.$ In this paper we take up the question of
reducing the sub-packetization value $l$ to make it approach the lower bound.
We construct an explicit family of optimal-access codes with $l=r^{\lceil
n/r\rceil},$ which differs from the optimal value by at most a factor of $r^2.$
These codes can be constructed over any finite field $F$ as long as $|F|\ge
r\lceil n/r\rceil,$ and afford low-complexity encoding and decoding procedures.
We also define a version of the repair problem that bridges the context of
regenerating codes and codes with locality constraints (LRC codes), calling it
group repair with optimal access. In this variation, we assume that the set of
$n=sm$ nodes is partitioned into $m$ repair groups of size $s,$ and require
that the amount of accessed data for repair is the smallest possible whenever
the $d$ helper nodes include all the other $s-1$ nodes from the same group as
the failed node. For this problem, we construct a family of codes with the
group optimal access property. These codes can be constructed over any field
$F$ of size $|F|\ge n,$ and also afford low-complexity encoding and decoding
procedures.


title: Tracing outflows in the AGN forbidden region with SINFONI

abstract:
  AGN driven outflows are invoked in numerical simulations to reproduce several
observed properties of local galaxies. The z > 1 epoch is of particular
interest as it was during this time that the volume averaged star formation and
the accretion rate of black holes were maximum. Radiatively driven outflows are
therefore believed to be common during this epoch. We aim to trace and
characterize outflows in AGN hosts with high mass accretion rates at z > 1
using integral field spectroscopy. We obtain spatially-resolved kinematics of
the [OIII]5007 line in two targets which reveal the morphology and spatial
extension of the outflows. We present J and H+K band SINFONI observations of 5
AGNs at 1.2 < z < 2.2. To maximize the chance of observing radiatively driven
outflows, our sample was pre-selected based on peculiar values of the Eddington
ratio and the hydrogen column density of the surrounding interstellar medium.
We observe high velocity (~600-1900 km/s) and kiloparsec scale extended ionized
outflows in at least 3 of our targets, using [OIII]5007 line kinematics tracing
the AGN narrow line region. We estimate the total mass of the outflow, the mass
outflow rate, and the kinetic power of the outflows based on theoretical models
and report on the uncertainties associated with them. We find mass outflow
rates of ~1-10 M_sun/yr for the sample presented in this paper. Based on the
high star formation rates of the host galaxies, the observed outflow kinetic
power and the expected power due to the AGN, we infer that both star formation
and AGN radiation could be the dominant source for the outflows. The outflow
models suffer from large uncertainties, hence we call for further detailed
observations for an accurate determination of the outflow properties to confirm
the exact source of these outflows.


title: Input-to-state Stability of Impulsive Systems with Different Jump Maps

abstract:
  The paper introduces sufficient conditions for input-to-state stability (ISS)
of a class of impulsive systems with jump maps that depend on time. Such
systems can naturally represent an interconnection of several impulsive systems
with different impulse time sequences. Using a concept of ISS-Lyapunov function
for subsystems a small-gain type theorem equipped with a new dwell-time
condition to verify ISS of an interconnection has been proven.


title:
Planck intermediate results. XLIX. Parity-violation constraints from
  polarization data

abstract:
  Parity violating extensions of the standard electromagnetic theory cause in
vacuo rotation of the plane of polarization of propagating photons. This
effect, also known as cosmic birefringence, impacts the cosmic microwave
background (CMB) anisotropy angular power spectra, producing non-vanishing
$T$--$B$ and $E$--$B$ correlations that are otherwise null when parity is a
symmetry. Here we present new constraints on an isotropic rotation,
parametrized by the angle $\alpha$, derived from Planck 2015 CMB polarization
data. To increase the robustness of our analyses, we employ two complementary
approaches, in harmonic space and in map space, the latter based on a peak
stacking technique. The two approaches provide estimates for $\alpha$ that are
in agreement within statistical uncertainties and very stable against several
consistency tests. Considering the $T$--$B$ and $E$--$B$ information jointly,
we find $\alpha = 0.31^{\circ} \pm 0.05^{\circ} \, ({\rm stat.})\, \pm
0.28^{\circ} \, ({\rm syst.})$ from the harmonic analysis and $\alpha =
0.35^{\circ} \pm 0.05^{\circ} \, ({\rm stat.})\, \pm 0.28^{\circ} \, ({\rm
syst.})$ from the stacking approach. These constraints are compatible with no
parity violation and are dominated by the systematic uncertainty in the
orientation of Planck's polarization-sensitive bolometers.


title: On The Relativity of Redshifts: Does Space Really "Expand"?

abstract:
  In classes on cosmology, students are often told that photons stretch as
space expands, but just how physical is this picture? Does space really expand?
In this article, we explore the notion of the redshift of light with Einstein's
general theory of relativity, showing that the core underpinning principles
reveal that redshifts are both simpler and more complex than you might naively
think. This has significant implications for the observed redshifting of
photons as they travel across the universe, often refereed to as the
cosmological redshift, and for the idea of expanding space.


title: Second Order Concentration via Logarithmic Sobolev Inequalities

abstract:
  We show sharpened forms of the concentration of measure phenomenon centered
at first order stochastic expansions. The bound are based on second order
difference operators and second order derivatives. Applications to functions on
the discrete cube and stochastic Hoeffding type expansions in mathematical
statistics are studied as well as linear eigenvalue statistics in random matrix
theory.


title: PAC-Bayesian Theory Meets Bayesian Inference

abstract:
  We exhibit a strong link between frequentist PAC-Bayesian risk bounds and the
Bayesian marginal likelihood. That is, for the negative log-likelihood loss
function, we show that the minimization of PAC-Bayesian generalization risk
bounds maximizes the Bayesian marginal likelihood. This provides an alternative
explanation to the Bayesian Occam's razor criteria, under the assumption that
the data is generated by an i.i.d distribution. Moreover, as the negative
log-likelihood is an unbounded loss function, we motivate and propose a
PAC-Bayesian theorem tailored for the sub-gamma loss family, and we show that
our approach is sound on classical Bayesian linear regression tasks.


title:
Computing the topological susceptibility from fixed topology QCD
  simulations

abstract:
  The topological susceptibility is an important quantity in QCD, which can be
computed using lattice methods. However, at a fine lattice spacing, or when
using high quality chirally symmetric quarks, algorithms which proceed in small
update steps --- in particular the HMC algorithm --- tend to get stuck in a
single topological sector. In such cases, the computation of the topological
susceptibility is not straightforward. Here, we explore two methods to extract
the topological susceptibility from lattice QCD simulations restricted to a
single topological sector. The first method is based on the correlation
function of the topological charge density, while the second method relies on
measuring the topological charge within spacetime subvolumes. Numerical results
for two-flavor QCD obtained by using both methods are presented.


title: Approximate implicitization using linear algebra

abstract:
  In this paper we consider a family of algorithms for approximate
implicitization of rational parametric curves and surfaces. The main
approximation tool in all of the approaches is the singular value
decomposition, and they are therefore well suited to floating point
implementation in computer aided geometric design (CAGD) systems. We unify the
approaches under the names of commonly known polynomial basis functions, and
consider various theoretical and practical aspects of the algorithms. We offer
new methods for a least squares approach to approximate implicitization using
orthogonal polynomials, which tend to be faster and more numerically stable
than some existing algorithms. We propose several simple propositions relating
the properties of the polynomial bases to their implicit approximation
properties.


title: Dialogue Concerning The Two Chief World Views

abstract:
  In 1632, Galileo Galilei wrote a book called \textit{Dialogue Concerning the
Two Chief World Systems} which compared the new Copernican model of the
universe with the old Ptolemaic model. His book took the form of a dialogue
between three philosophers, Salviati, a proponent of the Copernican model,
Simplicio, a proponent of the Ptolemaic model, and Sagredo, who was initially
open-minded and neutral. In this paper, I am going to use Galileo's idea to
present a dialogue between three modern philosophers, Mr. Spock, a proponent of
the view that $\mathsf{P} \neq \mathsf{NP}$, Professor Simpson, a proponent of
the view that $\mathsf{P} = \mathsf{NP}$, and Judge Wapner, who is initially
open-minded and neutral.


title: Arithmetical Semirings

abstract:
  We study the number of connected graphs with $n$ vertices that cannot be
written as the cartesian product of two graphs with fewer vertices. We give an
upper bound which implies that for large $n$ almost all graphs are both
connected and cartesian prime. For graphs with an even number of vertices, a
full asymptotic expansion is obtained. Our method, inspired by Knopfmacher's
theory of arithmetical semigroups, is based on reduction to Wright's asymptotic
expansion for the number of connected graphs with $n$ vertices.


title: An Upper Bound of Fully Entangled Fraction of Mixed States

abstract:
  We study the fully entangled fraction of a quantum state. An upper bound is
obtained for arbitrary bipartite system. This upper bound only depends on the
Frobenius norm of the state.


title:
CrowdSource: Automated Inference of High Level Malware Functionality
  from Low-Level Symbols Using a Crowd Trained Machine Learning Model

abstract:
  In this paper we introduce CrowdSource, a statistical natural language
processing system designed to make rapid inferences about malware functionality
based on printable character strings extracted from malware binaries.
CrowdSource "learns" a mapping between low-level language and high-level
software functionality by leveraging millions of web technical documents from
StackExchange, a popular network of technical question and answer sites, using
this mapping to infer malware capabilities. This paper describes our approach
and provides an evaluation of its accuracy and performance, demonstrating that
it can detect at least 14 high-level malware capabilities in unpacked malware
binaries with an average per-capability f-score of 0.86 and at a rate of tens
of thousands of binaries per day on commodity hardware.


title:
Screened exchange corrections to the random phase approximation from
  many-body perturbation theory

abstract:
  The random phase approximation (RPA) systematically overestimates the
magnitude of the correlation energy and generally underestimates cohesive
energies. This originates in part from the complete lack of exchange terms,
which would otherwise cancel Pauli exclusion principle violating (EPV)
contributions. The uncanceled EPV contributions also manifest themselves in
form of an unphysical negative pair density of spin-parallel electrons close to
electron-electron coalescence.
  We follow considerations of many-body perturbation theory to propose an
exchange correction that corrects the largest set of EPV contributions while
having the lowest possible computational complexity. The proposed method
exchanges adjacent particle/hole pairs in the RPA diagrams, considerably
improving the pair density of spin-parallel electrons close to coalescence in
the uniform electron gas (UEG). The accuracy of the correlation energy is
comparable to other variants of Second Order Screened Exchange (SOSEX)
corrections although it is slightly more accurate for the spin-polarized UEG.
Its computational complexity scales as $\mathcal O(N^5)$ or $\mathcal O(N^4)$
in orbital space or real space, respectively. Its memory requirement scales as
$\mathcal O(N^2)$.


title: Stability of Suspended Graphene under Casimir Force

abstract:
  We consider graphene sheet suspended above a conducting surface. Treating
graphene as an elastic membrane subjected to Casimir force, we study its
stability against attachment to the conductor. There exists a critical
elevation at the edges below which the central part of suspended graphene
nucleates a trunk that becomes attached to the conductor. The dependence of the
critical elevation on temperature and dimensions of the graphene sheet is
computed.


title: Edge states and skyrmion dynamics in nanostripes of frustrated magnets

abstract:
  Magnetic skyrmions are particle-like topological excitations recently
discovered in chiral magnets. Their small size, topological protection and the
ease with which they can be manipulated by electric currents generated much
interest in using skyrmions for information storage and processing. Recently,
it was suggested that skyrmions with additional degrees of freedom can exist in
magnetically frustrated materials. Here, we show that dynamics of skyrmions and
antiskyrmions in nanostripes of frustrated magnets is strongly affected by
complex spin states formed at the stripe edges. These states create multiple
edge channels which guide the skyrmion motion. Non-trivial topology of edge
states gives rise to complex current-induced dynamics, such as emission of
skyrmion-antiskyrmion pairs. The edge state topology can be controlled with an
electric current through the exchange of skyrmions and antiskyrmions between
the edges of a magnetic nanostructure. These results can lead to conceptually
new electronic devices.


title:
Noise-induced standing waves in oscillatory systems with time-delayed
  feedback

abstract:
  In oscillatory reaction-diffusion systems, time-delay feedback can lead to
the instability of uniform oscillations with respect to formation of standing
waves. Here, we investigate how the presence of additive, Gaussian white noise
can induce the appearance of standing waves. Combining analytical solutions of
the model with spatio-temporal simulations, we find that noise can promote
standing waves in regimes where the deterministic uniform oscillatory modes are
stabilized. As the deterministic phase boundary is approached, the
spatio-temporal correlations become stronger, such that even small noise can
induce standing waves in this parameter regime. With larger noise strengths,
standing waves could be induced at finite distances from the (deterministic)
phase boundary. The overall dynamics is defined through the interplay of noisy
forcing with the inherent reaction-diffusion dynamics.

categories: cond-mat.stat-mech cond-mat.soft nlin.PS physics.bio-ph