title: Probing Exotic Fermions from a Seesaw/Radiative Model at the LHC

abstract:
  There exist tree-level generalizations of the Type-I and Type-III seesaw
mechanisms that realize neutrino mass via low-energy effective operators with
d>5. However, these generalizations also give radiative masses that can
dominate the seesaw masses in regions of parameter space --- i.e. they are not
purely seesaw models, nor are they purely radiative models, but instead they
are something in between. A recent work detailed the remaining minimal models
of this type. Here we study the remaining model with d=9 and investigate the
collider phenomenology of the exotic quadruplet fermions it predicts. These
exotics can be pair produced at the LHC via electroweak interactions and their
subsequent decays produce a host of multi-lepton signals. Furthermore, the
branching fractions for events with distinct charged-leptons encode information
about both the neutrino mass hierarchy and the leptonic mixing phases. In large
regions of parameter-space discovery at the LHC with a 5 sigma significance is
viable for masses approaching the TeV scale.


title: Measurement of $\phi_s$ at LHCb

abstract:
  The study of CP violation in $B_s^0$ oscillations is one of the key goals of
the LHCb experiment. Effects are predicted to be very small in the Standard
Model but can be significantly enhanced in many models of new physics. We
present the world's best measurement of the CP-violating phase $\phi_s$ using
$B_s^0\to J/\psi KK$ and $B_s^0\to J/\psi\pi\pi$ decays.


title:
Mapping and Coding Design for Channel Coded Physical-layer Network
  Coding

abstract:
  Although BICM can significantly improves the BER performance by iteration
processing between the demapping and the decoding in a traditional receiver,
its design and performance in PNC system has fewer studied. This paper
investigates a bit interleaved coded modulation (BICM) scheme in a Gaussian
two-way relay channel operated with physical layer network coding (PNC). In
particular, we first present an iterative demapping and decoding framework
specially designed for PNC. After that, we compare different constellation
mapping schemes in this framework, with the convergence analysis by using the
EXIT chart. It is found that the anti-Gray mapping outperforms the Gray
mapping, which is the best mapping in the traditional decoding schemes.
Finally, the numerical simulation shows the better performance of our framework
and verifies the mapping design.


title: Secrecy Rate Study in Two-Hop Relay Channel with Finite Constellations

abstract:
  Two-hop security communication with an eavesdropper in wireless environment
is a hot research direction. The basic idea is that the destination,
simultaneously with the source, sends a jamming signal to interfere the
eavesdropper near to or co-located with the relay. Similar as physical layer
network coding, the friendly jamming signal will prevent the eavesdropper from
detecting the useful information originated from the source and will not affect
the destination on detecting the source information with the presence of the
known jamming signal. However, existing investigations are confined to Gaussian
distributed signals, which are seldom used in real systems. When finite
constellation signals are applied, the behavior of the secrecy rate becomes
very different. For example, the secrecy rate depends on phase difference
between the input signals with finite constellations, which is not observed
with Gaussian signals. In this paper, we investigate the secrecy capacity and
derive its upper bound for the two-hop relay model, by assuming an eavesdropper
near the relay and the widely used M-PSK modulation. With our upper bound, the
best and worst phase differences in high SNR region are then given. Numerical
studies verify our analysis and show that the derived upper bound is relatively
tight.


title:
Exploring Low Luminosity Quasar Diversity at z ~ 2.5 with the Gran
  Telescopio Canarias

abstract:
  We present preliminary results from a pencil-beam spectroscopic survey of
low-luminosity quasars at z ~ 2.2-2.5. Our goal is to compare these sources
with low redshift analogues of similar luminosity. High s/n and moderate
resolution spectra were obtained for 15 sources using the faint object
spectrograph Osiris on the 10m Gran Telescopio Canarias. The new data make
possible an almost unprecedented comparison between sources with the same
(moderate) luminosity at widely different cosmic epochs. Preliminary analysis
of our spectra confirms the presence of a relatively evolved population of
quasars radiating at modest Eddington ratios. A notable difference between the
low and high z quasars may involve the presence of lower metallicity quasars at
high redshift.


title:
Phase Transition to Insulating State from Quantum Hall State by
  Current-Induced Nuclear Spin Polarization

abstract:
  We investigate the resistance enhancement state (RES) where the
magnetoresistance of the $\nu = 2/3$ fractional quantum Hall state (FQHS) is
increased with dynamic nuclear spin polarization (DNP) induced by a large
electric current. After inducing DNP, we measure the temperature dependence of
the magnetoresistance by a small current over a short period of time. We find
that the FQHS makes a phase transition to an insulating state. By measuring the
Hall resistance in the insulating state, we find that the RES exhibits a
quantized Hall resistance. We discuss the RES in association with the Anderson
localization.


title:
Measuring galaxy [OII] emission line doublet with future ground-based
  wide-field spectroscopic surveys

abstract:
  The next generation of wide-field spectroscopic redshift surveys will map the
large-scale galaxy distribution in the redshift range 0.7< z<2 to measure
baryonic acoustic oscillations (BAO). The primary optical signature used in
this redshift range comes from the [OII] emission line doublet, which provides
a unique redshift identification that can minimize confusion with other single
emission lines. To derive the required spectrograph resolution for these
redshift surveys, we simulate observations of the [OII] (3727,3729) doublet for
various instrument resolutions, and line velocities. We foresee two strategies
about the choice of the resolution for future spectrographs for BAO surveys.
For bright [OII] emitter surveys ([OII] flux ~30.10^{-17} erg /cm2/s like
SDSS-IV/eBOSS), a resolution of R~3300 allows the separation of 90 percent of
the doublets. The impact of the sky lines on the completeness in redshift is
less than 6 percent. For faint [OII] emitter surveys ([OII] flux ~10.10^{-17}
erg /cm2/s like DESi), the detection improves continuously with resolution, so
we recommend the highest possible resolution, the limit being given by the
number of pixels (4k by 4k) on the detector and the number of spectroscopic
channels (2 or 3).


title:
Spectral functions of the simplest even order ordinary differential
  operator

abstract:
  We consider the minimal differential operator A generated in $L^2(0,\infty)$
by the differential expression $l(y) = (-1)^n y^{(2n)}$. Using the technique of
boundary triplets and the corresponding Weyl functions, we find explicit form
of the characteristic matrix and the corresponding spectral function for the
Friedrichs and Krein extensions of the operator A.


title:
Darboux transformation and solutions of the two-component
  Hirota-Maxwell-Bloch system

abstract:
  In this paper, we derive n-fold Darboux transformation of the two-component
Hirota and the Maxwell-Bloch(TH-MB) equations and its determinant
representation. Using Darboux determinant representation, we provide soliton
solutions, positon solutions of the TH-MB equations.


title: Automorphisms of Cayley graphs on generalised dicyclic groups

abstract:
  A graph is called a GRR if its automorphism group acts regularly on its
vertex-set. Such a graph is necessarily a Cayley graph. Godsil has shown that
there are only two infinite families of finite groups that do not admit GRRs :
abelian groups and generalised dicyclic groups. Indeed, any Cayley graph on
such a group admits specific additional graph automorphisms that depend only on
the group. Recently, Dobson and the last two authors showed that almost all
Cayley graphs on abelian groups admit no automorphisms other than these obvious
necessary ones. In this paper, we prove the analogous result for Cayley graphs
on the remaining family of exceptional groups: generalised dicyclic groups.


title: Photocurrent-based detection of Terahertz radiation in graphene

abstract:
  Graphene is a promising candidate for the development of detectors of
Terahertz (THz) radiation. A well-known detection scheme due to Dyakonov and
Shur exploits the confinement of plasma waves in a field-effect transistor
(FET), whereby a dc photovoltage is generated in response to a THz field. This
scheme has already been experimentally studied in a graphene FET [L. Vicarelli
et al., Nature Mat. 11, 865 (2012)]. In the quest for devices with a better
signal-to-noise ratio, we theoretically investigate a plasma-wave photodetector
in which a dc photocurrent is generated in a graphene FET. The rectified
current features a peculiar change of sign when the frequency of the incoming
radiation matches an even multiple of the fundamental frequency of plasma waves
in the FET channel. The noise equivalent power per unit bandwidth of our device
is shown to be much smaller than that of a Dyakonov-Shur detector in a wide
spectral range.


title:
Fluctuation theorem for quantum electron transport in mesoscopic
  circuits

abstract:
  We study the statistical properties of currents in two particular systems of
capacitively coupled parallel transport channels. In the first system, each
transport channel contains a single quantum dot in contact with two electron
reservoirs. The second system we study is constituted of a double quantum dot
coupled to two electrodes and probed by a quantum point contact detector.
Thermodynamic forces are applied to each transport channel that generate
fluctuating stationary currents. The full counting statistics of the currents
is obtained starting from a microscopic Hamiltonian describing the electron
dynamics. We verify that the joined probability distribution of the currents in
each channel satisfies a fluctuation theorem in the long-time limit. The issue
of single-current fluctuation theorems for the marginal distribution of the
currents in one of the two channels is also investigated. We show that in the
limit of large current ratio between both channels, a single-current
fluctuation theorem is satisfied individually for the slower circuit in
agreement with experimental observations. This theorem involves an effective
affinity which depends on the thermodynamic forces applied to both channels and
the specific features of the system considered. A detailed study of the
effective affinity is made for the two aforementioned systems. Besides, we
introduce a criteria on the initial condition of the transport channels for the
observation of a fluctuation theorem at any time. This criteria is extended to
the case of single-current fluctuation theorems. Finally, we perform the
nonequilibrium thermodynamic analysis of a double quantum dot probed by a
quantum point contact in the presence of temperature and chemical potential
differences between the electrodes. A thermal machine is studied and shown to
reach highest efficiencies at maximum power by fine tuning the double quantum
dot spectrum.


title:
Games and Culture: Using Online-gaming Data to Cluster Chinese Regional
  Cultures

abstract:
  To identify cluster of societies and cultures is not easy in subject to the
availability of data. In this study, we propose a novel method to cluster
Chinese regional cultures. Using geotagged online-gaming data of Chinese
internet users playing online card and board games with regional features, 336
Chinese cities are grouped into 17 clusters. The distribution of clustering
units shows great geographical proximity when the boundary of the clusters
coincides well with the geographical boundary of provinces.


title:
Elastic scattering of a Bose-Einstein condensate at a potential
  landscape

abstract:
  We investigate the elastic scattering of Bose-Einstein condensates at shallow
periodic and disorder potentials. We show that the collective scattering of the
macroscopic quantum object couples to internal degrees of freedom of the
Bose-Einstein condensate such that the Bose-Einstein condensate gets depleted.
As a precursor for the excitation of the Bose-Einstein condensate we observe
wave chaos within a mean-field theory.


title:
Determinant quantum Monte Carlo study of exciton condensation in the
  bilayer Hubbard model

abstract:
  We studied the possibility of exciton condensation in a strongly correlated
bilayer extended Hubbard model using Determinant Quantum Monte Carlo. To model
both the onsite repulsion U and the interlayer interaction V we introduced a
novel update scheme extending the standard Sherman-Morrison update. We observe
that the sign problem increases dramatically with the inclusion of the
interlayer interaction V, which prohibits at this stage a unequivocal
conclusion regarding the presence of exciton condensation. However, enhancement
of the interlayer tunneling results suggest that the strongest exciton
condensation tendency lies around 10-20 % p/n-doping. Magnetic properties and
conductivity turn out to be relatively independent of the interlayer
interaction.


title: Quasi-specular reflection from particulate media

abstract:
  Specular reflection is known to play an important role in many fields of
scattering applications, e.g., in remote sensing, computer graphics,
optimization of visual appearance of industrial products. Usually it can be
assumed that the object has a solid surface and that the properties of the
surface will dictate the behavior of the specular component. In this study I
will show that media consisting of wavelength-sized particles can also have a
quasi-specular reflection in cases where there is ordered structure in the
media. I will also show that the quasi-specular reflection in particulate media
is more than just a surface effect, and planar particle arrangement below the
very surface can give arise to quasi-specular reflection. This study shows that
the quasi-specular reflection may contribute in some cases in the
backscattering direction, together with coherent backscattering and
shadow-hiding effects.


title:
Interplay between direct and crossed Andreev reflections in hybrid
  nano-structures

abstract:
  The interplay between various many body effects in a quantum dot attached to
two normal and one superconducting lead is considered in the limit of large
superconducting gap. By the proximity effect the superconducting lead induces
pairing correlations on the quantum dot. In the subgap region one observes the
anomalous tunneling via direct and crossed Andreev scattering, whereas the
usual single particle electronic transfer is suppressed. The interactions of
electrons on the dot leading to such phenomena as the Coulomb blockade and the
Kondo effect severely modify the currents flowing in the system. In particular:
(i) they prevent the existence of the negative differential conductance
observed for non-interacting quantum dot over the whole range of voltages, (ii)
affect the distribution of the currents as function of the applied voltage and
(iii) lead to the appearance of additional low bias feature due to the
formation of the Abrikosov-Suhl resonance. The non-local correlations in the
Coulomb blockade regime are most pronounced for the particle-hole symmetric dot
and thus can be easily tuned by means of gate voltage. They are observed even
in the Kondo regime and dominate the behavior close to the Abrikosov-Suhl
resonance showing convincingly that Kondo correlations do not destroy subtle
entanglement between electrons.


title:
Superstrong nature of covalently bonded glass-forming liquids at select
  compositions

abstract:
  Variation of fragility (m) of specially homogenized GexSe100-x melts are
established from complex specific heat measurements, and show m(x) has a global
minimum at an extremely low value (m=14.8(0.5)) in the 21.5%<x<23% range of Ge.
Outside of that compositional range, m(x) then increases at first rapidly then
slowly to about m=25-30. By directly mapping melt stoichiometry as a function
of reaction time at a fixed temperature T>Tg, we observe a slowdown of
melt-homogenization by the super-strong melt compositions, 21.5%<x<23%. This
range furthermore appears to be correlated to the one observed between the
flexible and stressed rigid phase in network glasses. These spectacular
features underscore the crucial role played by topology and rigidity in the
properties of network-forming liquids and glasses which are highlighted when
fragility is represented as a function of variables tracking the effect of
rigidity. Finally, we investigate the fragility-glass transition temperature
relationship, and find that reported scaling laws do not apply in the flexible
phase, while being valid for intermediate and stressed rigid compositions.


title: Coalescence of binary neutron stars in a scalar-tensor theory of gravity

abstract:
  We carry out numerical-relativity simulations of coalescing binary neutron
stars in a scalar-tensor theory that admits spontaneous scalarization. We model
neutron stars with realistic equations of state. We choose the free parameters
of the theory taking into account the constraints imposed by the latest
observations of neutron-star-- white-dwarf binaries with pulsar timing. We show
that even within those severe constraints, scalarization can still affect the
evolution of the binary neutron stars not only during the late inspiral, but
also during the merger stage. We also confirm that even when both neutron stars
have quite small scalar charge at large separations, they can be strongly
scalarized dynamically during the final stages of the inspiral. In particular,
we identify the binary parameters for which scalarization occurs either during
the late inspiral or only after the onset of the merger when a remnant,
supramassive or hypermassive neutron star is formed. We also discuss how those
results can impact the extraction of physical information on gravitational
waves once they are detected.


title:
Conflict Diagnostics in Directed Acyclic Graphs, with Applications in
  Bayesian Evidence Synthesis

abstract:
  Complex stochastic models represented by directed acyclic graphs (DAGs) are
increasingly employed to synthesise multiple, imperfect and disparate sources
of evidence, to estimate quantities that are difficult to measure directly. The
various data sources are dependent on shared parameters and hence have the
potential to conflict with each other, as well as with the model. In a Bayesian
framework, the model consists of three components: the prior distribution, the
assumed form of the likelihood and structural assumptions. Any of these
components may be incompatible with the observed data. The detection and
quantification of such conflict and of data sources that are inconsistent with
each other is therefore a crucial component of the model criticism process. We
first review Bayesian model criticism, with a focus on conflict detection,
before describing a general diagnostic for detecting and quantifying conflict
between the evidence in different partitions of a DAG. The diagnostic is a
p-value based on splitting the information contributing to inference about a
"separator" node or group of nodes into two independent groups and testing
whether the two groups result in the same inference about the separator
node(s). We illustrate the method with three comprehensive examples: an
evidence synthesis to estimate HIV prevalence; an evidence synthesis to
estimate influenza case-severity; and a hierarchical growth model for rat
weights.


title:
Probabilistic Analysis of LCF Crack Initiation Life of a Turbine Blade
  under Thermomechanical Loading

abstract:
  An accurate assessment for fatigue damage as a function of activation and
deactivation cycles is vital for the design of many engineering parts. In this
paper we extend the probabilistic and local approach to this problem proposed
in [1,2] and [3] to the case of non-constant temperature fields and
thermomechanical loading. The method has been implemented as a finite element
postprocessor and applied to an example case of a gas-turbine blade which is
made of a conventionally cast nickel base superalloy.


title:
Effects of the continuous spontaneous localization model in the regime
  of large localization length scale

abstract:
  Working in the limit in which the localization length scale is large compared
to other relevant length scales we examine three experimental situations with
the continuous spontaneous localization (CSL) model---a well-motivated
alternative to standard quantum theory. These are the two-slit experiment;
scattering from a potential barrier; and the release of two non-interacting
particles simultaneously from a potential trap. In each case we calculate the
diagonal part of the time evolved density matrix giving a probability density
function over final measured states. The case of the two-slit experiment is
already well understood and we reproduce some known conditions for observing
loss of interference. The other examples have not previously been examined in
the context of CSL. For scattering from a potential barrier we find that the
probability of reflection is unchanged by CSL, however, the momentum state is
spread in a characteristic way. For the case of two particles released
simultaneously from a trap we find that it is more likely that the particles
diffuse in the same direction than would happen if the particles behaved
independently. We assess the possibility of observing these effects.


title: A Comparison theorem on projective Finsler geometry

abstract:
  Here, a non-linear analysis method is applied rather than classical one to
study projective Finsler geometry. More intuitively, by means of an inequality
on Ricci-Finsler curvature, a projectively invariant pseudo-distance is
introduced and an analogous of Schwarz' lemma in Finsler geometry is proved.
Next, the Schwarz' lemma is applied to show that the introduced pseudo-distance
is a distance. This projectively invariant distance will be served in
continuation of this work to investigate Einstein-Finsler spaces and classify
Finsler spaces as well.


title: Cycle packing

abstract:
  In the 1960s, Erd\H{o}s and Gallai conjectured that the edge set of every
graph on n vertices can be partitioned into O(n) cycles and edges. They
observed that one can easily get an O(n log n) upper bound by repeatedly
removing the edges of the longest cycle. We make the first progress on this
problem, showing that O(n log log n) cycles and edges suffice. We also prove
the Erd\H{o}s-Gallai conjecture for random graphs and for graphs with linear
minimum degree.


title:
A test of the continuous spontaneous localization model involving two
  particles

abstract:
  We describe a previously unexplored effect of the continuous spontaneous
localization model whereby a correlation develops in the distributions of two
nearby non-interacting particles following a period of diffusion. We propose
the use of this effect as an experimental test differentiating between the
continuous spontaneous localization model and standard quantum theory. The test
involves building a joint probability distribution for the locations of the two
particles by repeatedly releasing them from two nearby traps and subsequently
measuring their positions after a brief period of time. We examine the scales
of time, trap size, and particle mass necessary for observation.


title: Combinatorial properties of Temperley Lieb algebras

abstract:
  We consider two families of polynomials that play the same role in the
Temperley Lieb algebra of a Coxeter group as the Kazhdan Lusztig and R
polynomials play in the Hecke algebra of the group. We study these polynomials
from a combinatorial point of view. More precisely we obtain recursions, non
recursive formulas, symmetry properties, and expressions for the constant
terms, of these polynomials.


title:
The Structure of Liquid Water Emerging from the Vibrational
  Spectroscopy: Interpretation with QED Theory

abstract:
  We report an analysis of the stretching peak appearing in the IR experimental
spectra of liquid water. In the literature, ATR-IR spectroscopic measurements
were repeatedly performed in a wide range of temperature and gave rise to a
lively debate among scientists. In particular a two components model related to
H-bond complexes of different strength have been proposed in order to justify
the existence of two types of molecules as it appears from the spectroscopic
data. At the opposite, Molecular Dynamics simulations support a multistate
(continuum) system of H bond having different strength giving rise to a
(locally) tetrahedral description of liquid water. We will show that liquid
water is a quantum two-level system according to the predictions of Quantum
Electrodynamics (QED) and that several features (the asymmetric band profile,
the existence of an isosbestic point and the modifications of the vibrational
stretching band with the temperature) cannot be fully justified in the realm of
a classical picture. In particular the differences of energy and entropy
between the two phases are estimated from the experimental data and compared
with the prediction of QED showing a remarkable agreement. The behavior of
water near hydrophilic surfaces is also discussed and several feature of the so
called Exclusion Zone observed by several authors are evaluated according to
the two level system model.


title: Combination of classifying spaces for proper actions

abstract:
  Given a group action on a simplicial complex such that each simplex
stabiliser admits a cocompact model of classifying space for proper actions, we
give conditions implying the existence of a cocompact model of classifying
space for proper actions for the whole group. This is used to generalise
previous combination results for boundaries of groups and hyperbolic groups.


title:
Propagation of stationary exothermic transition front with nonstationary
  oscillatory tail

abstract:
  We consider a propagation of exotermic transition front in a discrete
conservative oscillatory chain. Adequate description of such fronts is a key
point in prediction of important transient phenomena, including phase
transitions and topochemical reactions. Due to constant energy supply, the
transition front can propagate with high velocities, precluding any
continuum-based considerations. Stationary propagation of the front is
accompanied by formation of a non-stationary oscillatory tail with complicated
internal structure. We demonstrate that the structure of the oscillatory tail
is related to a relationship between phase and group velocities of the
oscillations. We suggest also an approximate analytic procedure, which allows
one to determine all basic characteristics of the propagation process: velocity
and width of the front, frequency and amplitude of the after-front
oscillations, as well as the structure of the oscillatory tail. As an example,
we consider a simple case of biharmonic double-well on-site potential. Numeric
results nicely conform to the analytic predictions.


title: On a projectively invariant distance on Einstein Finsler spaces

abstract:
  In this work an intrinsic projectively invariant distance is used to
establish a new approach to the study of projective geometry in Finsler space.
It is shown that the projectively invariant distance previously defined is a
constant multiple of the Finsler distance in certain case. As a consequence,
two projectively related complete Einstein Finsler spaces with constant
negative scalar curvature are homothetic. Evidently, this will be true for
Finsler spaces of constant flag curvature as well.


title: Realization of quantum diffraction of a thermal flux

abstract:
  The first evidence of the dc Josephson effect dates back to 1963 when J. S.
Rowell measured the diffraction pattern of the critical current flowing through
a single superconducting tunnel junction subjected to an in-plane magnetic
field. Interference of Josephson currents through two tunnel junctions
connected in parallel was achieved one year later leading to the first ever
superconducting quantum interferometer. The latter, together with Rowell's
observations, constituted the unequivocal demonstration of the Josephson
supercurrent-phase relation. Yet, the Josephson effect has further profound
implications going beyond electrical transport, as the interplay between the
Cooper condensate and unpaired electrons provides thermal flow through the
junction with phase coherence as well. Here we report the first demonstration
of quantum diffraction of a heat flux showing that a temperature-biased single
Josephson junction is exploited as a diffractor for thermal currents.
Specifically, thermal diffraction manifests itself with a peculiar modulation
of the electron temperature in a small metallic electrode nearby-contacted to
the junction when sweeping the magnetic flux $\Phi$. Remarkably, the observed
temperature dependence exhibits $\Phi$-symmetry and a clear reminiscence with a
Fraunhofer-like modulation pattern, as expected fingerprints for a quantum
diffraction phenomenon. Our results confirm a pristine prediction of quantum
heat transport and, joined with double-junction heat interferometry
demonstrated in Nature 492, 401 (2012), exemplify the complementary and
conclusive proof of the existence of phase-dependent thermal currents in
Josephson-coupled superconductors. This approach combined with well-known
methods for phase-biasing superconducting circuits provides with a novel tool
for mastering heat fluxes at the nanoscale.


title: A physical derivation of the Kerr-Newman black hole solution

abstract:
  According to the no-hair theorem, the Kerr-Newman black hole solution
represents the most general asymptotically flat, stationary (electro-) vacuum
black hole solution in general relativity. The procedure described here shows
how this solution can indeed be constructed as the unique solution to the
corresponding boundary value problem of the axially symmetric Einstein-Maxwell
equations in a straightforward manner.


title:
Scientific prospects in soft gamma-ray astronomy enabled by the LAUE
  project

abstract:
  This paper summarizes the development of a successful project, LAUE,
supported by the Italian Space Agency (ASI) and devoted to the development of
long focal length (up to 100 m) Laue lenses for hard X--/soft gamma--ray
astronomy (80-600 keV). The apparatus is ready and the assembling of a
prototype lens petal is ongoing. The great achievement of this project is the
use of bent crystals. From measurements obtained on single crystals and from
simulations, we have estimated the expected Point Spread Function and thus the
sensitivity of a lens made of petals. The expected sensitivity is a few
$\times10^{-8}$ photons cm$^{-2}$ s$^{-1}$ keV$^{-1}$. We discuss a number of
open astrophysical questions that can settled with such an instrument aboard a
free-flying satellite.


title: Development of a GEM based detector for the CBM Muon Chamber (MUCH)

abstract:
  The characteristics of triple GEM detectors have been studied systematically
by using cosmic ray muons. The minimum ionizing particle (MIP) spectra has been
taken for different GEM voltage setting. Efficiency of GEM detector has been
measured for cosmic ray. At high rate operation of GEMs the value of the
protection resistor influences the gain and the stability. This feature has
been investigated varying both the rate and the value of the protection
resistor. This measurement has been performed using both X-ray generator and
Fe55 source. The ageing and long-term stability of GEM based detectors has been
studied employing both X-ray generator and Fe55 source. The ageing study of one
GEM module is performed by using a 8 keV Cu X-ray generator to verify the
stability and integrity of the GEM detectors over a longer period of time. The
accumulated charge on the detector is calculated from the rate of the X-ray and
the average gain of the detector. The details of the measurement and results
has been described in this article.


title:
A Closer Look at Gaugino Masses in Pure Gravity Mediation Model/Minimal
  Split SUSY Model

abstract:
  We take a closer look at the gaugino masses in the context of pure gravity
mediation models/minimal split SUSY models. We see that the gaugino mass
spectrum has a richer structure in the presence of vector-like matter fields
even when they couple to the supersymmetry breaking sector only through Planck
suppressed operators. For example, the gluino mass can be much lighter than in
anomaly mediation, enhancing the detectability of the gluino at the LHC
experiments. The rich gaugino spectrum also allows new possibilities for dark
matter scenarios such as the bino-wino co-annihilation, bino-gluino
co-annihilation, or even wino-gluino co-annihilation scenarios, which affects
future collider experiments as well as dark matter search experiments.


title: Stochastic Schr\"odinger Equations for Markovian and non-Markovian cases

abstract:
  Firstly, the Markovian stochastic Schr\"odinger equations are presented,
together with their connections with the theory of measurements in continuous
time. Moreover, the stochastic evolution equations are translated into a
simulation algorithm, which is illustrated by two concrete examples - the
damped harmonic oscillator and a two-level atom with homodyne photodetection.
Then, we consider how to introduce memory effects in the stochastic
Schr\"odinger equation via coloured noise. Specifically, the approach by using
the Ornstein-Uhlenbeck process is illustrated and a simulation for the
non-Markovian process proposed. Finally, an analytical approximation technique
is tested with the help of the stochastic simulation in a model of a
dissipative qubit.


title: A new Bayesian approach to the reconstruction of spectral functions

abstract:
  We present a novel approach for the reconstruction of spectra from Euclidean
correlator data that makes close contact to modern Bayesian concepts. It is
based upon an axiomatically justified dimensionless prior distribution, which
in the case of constant prior function $m(\omega)$ only imprints smoothness on
the reconstructed spectrum. In addition we are able to analytically integrate
out the only relevant overall hyper-parameter $\alpha$ in the prior, removing
the necessity for Gaussian approximations found e.g. in the Maximum Entropy
Method. Using a quasi-Newton minimizer and high-precision arithmetic, we are
then able to find the unique global extremum of $P[\rho|D]$ in the full
$N_\omega\gg N_\tau$ dimensional search space. The method actually yields
gradually improving reconstruction results if the quality of the supplied input
data increases, without introducing artificial peak structures, often
encountered in the MEM. To support these statements we present mock data
analyses for the case of zero width delta peaks and more realistic scenarios,
based on the perturbative Euclidean Wilson Loop as well as the Wilson Line
correlator in Coulomb gauge.


title:
One approach for determining susceptibilities and order parameters in
  multi-band Hubbard model

abstract:
  We present an approach for determining susceptibilities and order parameters
in multi-band Hubbard model within functional renormalization group method, and
apply it to study various instabilities of the FeAs-based high temperature
superconductor. First, we derive the formulae of susceptibilities and order
parameters of superconducting parings, spin density waves and charge density
waves with diverse wave vectors which could occur in multi-band Hubbard model.
Second, we apply it to the FeAs-based high temperature superconductor and find
an electronic-driven superconducting pairing instability within a five band
model with pure repulsive interactions. Our study shows that for doping of our
concern, there is competition between antiferromagnetic and superconducting
instabilities. In addition, we show that for doping of 0.1, the susceptibility
of extended s-wave pairing is dominant over others, while a staggered
superconducting pairing with has the second largest value of susceptibility.


title:
Pierre Auger Observatory and Telescope Array: Joint Contributions to the
  33rd International Cosmic Ray Conference (ICRC 2013)

abstract:
  Joint contributions of the Pierre Auger and Telescope Array Collaborations to
the 33rd International Cosmic Ray Conference, Rio de Janeiro, Brazil, July
2013: cross-calibration of the fluorescence telescopes, large scale
anisotropies and mass composition.


title:
Algorithm for Resource Redistribution Required for Recovery of Society
  after Large Scale Disasters

abstract:
  The recovery of society after a large scale disaster generally consists of
two phases, short- and long-term recoveries. The problem of short-term recovery
is rather close to the problem of resilience in their goal, namely, bouncing
the damaged system back to the operating standards. The present paper proposes
an algorithm for the vital resource redistribution required for implementation
of the short-term recovery. The developed model is based on the cooperative
interaction of cities during the resource redistribution, ordering the cities
according to their priority in resource delivery, and a generating a
semi-optimal plan for the desired redistribution. Nonlinear effects caused by
the city limit capacities are taken into account. Two types of systems,
"uniform" and "centralized", are studied numerically. In particular it is
demonstrated that the cooperation effects are able to shorten substantially the
duration of the process required for its implementation.


title:
The constancy of principal curvatures of curvature-adapted submanifolds
  in symmetric spaces

abstract:
  In this paper, we investigate complete curvature-adapted submanifolds with
maximal flat section and trivial normal holonomy group in symmetric spaces of
compact type or non-compact type under certain condition, and derive the
constancy of the principal curvatures of such submanifolds. As its result, we
can derive that such submanifolds are isoparametric.


title: Playing with Subshifts

abstract:
  We study the class of word-building games, where two players pick letters
from a finite alphabet to construct a finite or infinite word. The outcome is
determined by whether the resulting word lies in a prescribed set (a win for
player $A$) or not (a win for player $B$). We focus on symbolic dynamical
games, where the target set is a subshift. We investigate the relation between
the target subshift and the set of turn orders for which $A$ has a winning
strategy.


title:
Blow-up scaling and global behaviour of solutions of the bi-Laplace
  equation via pencil operators

abstract:
  As the main problem, the bi-Laplace equation $\Delta^2u=0
(\Delta=D_x^2+D_y^2)$ in a bounded domain $\Omega \subset \re^2$, with
inhomogeneous Dirichlet or Navier-type conditions on the smooth boundary
$\partial \Omega$ is considered. In addition, there is a finite collection of
curves
  $$\Gamma = \Gamma_1\cup...\cup\Gamma_m \subset \Omega, \quad \mbox{on which
we assume homogeneous Dirichlet} \quad u=0,$$ focusing at the origin $0 \in
\Omega$ (the analysis would be similar for any other point). This makes the
above elliptic problem overdetermined. Possible types of the behaviour of
solution $u(x,y)$ at the tip $0$ of such admissible multiple cracks, being a
singularity point, are described, on the basis of blow-up scaling techniques
and spectral theory of pencils of non self-adjoint operators. Typical types of
admissible cracks are shown to be governed by nodal sets of a countable family
of harmonic polynomials, which are now represented as pencil eigenfunctions,
instead of their classical representation via a standard Sturm--Liouville
problem. Eventually, for a fixed admissible crack formation at the origin, this
allows us to describe all boundary data, which can generate such a blow-up
crack structure. In particular, it is shown how the co-dimension of this data
set increases with the number of asymptotically straight-line cracks focusing
at 0.


title:
Patterns without patches: Hierarchical assembly of complex structures
  from simple building blocks

abstract:
  Nanoparticles with "sticky patches" have long been proposed as building
blocks for the self-assembly of complex structures. The synthetic realizability
of such patchy particles, however, greatly lags behind predictions of patterns
they could form. Using computer simulations, we show that structures of the
same genre can be obtained from a solution of simple isotropic spheres,
provided control only over their sizes and a small number of binding
affinities. In a first step, finite clusters of well-defined structure and
composition emerge from natural dynamics with high yield. In effect a kind of
patchy particle, these clusters can further assemble into a variety of complex
superstructures, including filamentous networks, ordered sheets, and highly
porous crystals.


title: Weighted Laplacians, cocycles and recursion relations

abstract:
  Hodge's formula represents the gravitational MHV amplitude as the determinant
of a minor of a certain matrix. When expanded, this determinant becomes a sum
over weighted trees, which is the form of the MHV formula first obtained by
Bern, Dixon, Perelstein, Rozowsky and rediscovered by Nguyen, Spradlin,
Volovich and Wen. The gravity MHV amplitude satisfies the Britto, Cachazo, Feng
and Witten recursion relation. The main building block of the MHV amplitude,
the so-called half-soft function, satisfies a different, Berends-Giele-type
recursion relation. We show that all these facts are illustrations to a more
general story.
  We consider a weighted Laplacian for a complete graph of n vertices. The
matrix tree theorem states that its diagonal minor determinants are all equal
and given by a sum over spanning trees. We show that, for any choice of a
cocycle on the graph, the minor determinants satisfy a Berends-Giele as well as
Britto-Cachazo-Feng-Witten type recursion relation. Our proofs are purely
combinatorial.


title: Constructions with Countable Subshifts of Finite Type

abstract:
  We present constructions of countable two-dimensional subshifts of finite
type (SFTs) with interesting properties. Our main focus is on properties of the
topological derivatives and subpattern posets of these objects. We present a
countable SFT whose iterated derivatives are maximally complex from the
computational point of view, constructions of countable SFTs with high
Cantor-Bendixson ranks, a countable SFT whose subpattern poset contains an
infinite descending chain and a countable SFT whose subpattern poset contains
all finite posets. When possible, we make these constructions deterministic,
and ensure the sets of rows are very simple as one-dimensional subshifts.


title: Variance-based sensitivity analysis for stochastic chemical kinetics

abstract:
  Sensitivity analysis is a process of computing sensitivity indices, which are
certain measures of importance of parameters in influencing the outputs of
mathematical models. Sensitivity indices computed in variance-based sensitivity
analysis yield quantitative answers to questions like how much on average the
variance of model output, measuring its uncertainty, decreases, if exact values
of certain unknown parameters are determined, e. g. in an experiment. We
propose new schemes for estimation of variance-based sensitivity indices of
outputs of stochastic models, their conditional expectations, and histograms
given the parameters. Unbiased estimators obtained in these schemes can be used
in a Monte Carlo (MC) procedure approximating sensitivity indices. We derive
relations between variances of final estimators of MC procedures making the
same number of evaluations of given function, but using different schemes, both
for the newly introduced schemes and for some used before in the literature.
Numerical experiment for a discrete state stochastic Markov model of a chemical
reaction network (DM) shows that our method can lead to much lower error than
method analogous to the one offered by Degasperi et al. Further numerical
experiments demonstrate that the application of random time change (RTC)
algorithm due to Rathinam et al. for simulation of DM can lead to over 30 times
lower variance of estimators of certain sensitivity indices than when
Gillespie's direct (GD) method is used, and that this variance may
significantly depend on the order of reactions in GD method. We provide some
intuitions explaining these effects. We generalize measures used for comparing
dispersion of different distributions, such as coefficient of variation and
Fano factor to the random parameters case, in a way that they can be computed
along with variance-based sensitivity indices.


title:
Piezoelectric Drop-on-Demand Inkjet Printing of Rat Fibroblast Cells:
  Survivability Study and Pattern Printing

abstract:
  A novel piezoelectric, drop-on-demand (DOD) inkjet system has been developed
and used to print L929 rat fibroblast cells. We investigate the survivability
of the cells subjected to the large stresses during the printing process. These
stresses are varied by changing the diameter of the orifice (36 to 119 microns)
through which the cells are dispensed, as well as changing the electrical pulse
used to drive the piezoelectric element. It is shown that for the smallest 36
microns diameter orifice, cell survival rates fall from 95% to approximately
76% when the ejection velocity is increased from 2 to 16 m/s. This decrease in
survival rates is less significant when the larger orifice diameters of 81
microns and 119 microns are used. Analysis shows that there is a clear inverse
relationship between cell survival rates and the mean shear rates during drop
formation. By using the same printing set-up, fibroblast cells are printed onto
alginate and collagen into patterns. Printed cells are cultured over a period
of days to verify their long-term viability. Fibroblasts printed onto the
collagen are found to successfully adhere, spread and proliferate, subsequently
forming a denser patterns after 5 days in culture. Cell agglomeration is found
to affect the printing performance, especially for the printhead with the
smallest orifice, leading to frequent clogging of the nozzle. We also study the
number of cells in each droplet, when printed under optimal conditions. The
probability density of this number follows a binomial distribution, which
consistent with a uniform distribution of cells in the medium and within the
printhead.


title:
Variance-based sensitivity analysis and orthogonal approximations for
  stochastic models

abstract:
  We develop new unbiased estimators of a number of quantities defined for
functions of conditional moments, like conditional expectations and variances,
of functions of two independent random variables given the first variable,
including certain outputs of stochastic models given the models parameters.
These quantities include variance-based sensitivity indices, mean squared error
of approximation with functions of the first variable, orthogonal projection
coefficients, and newly defined nonlinearity coefficients. We define the above
estimators and analyze their performance in Monte Carlo procedures using
generalized concept of an estimation scheme and its inefficiency constant. In
numerical simulations of chemical reaction networks, using the Gillespie's
direct and random time change methods, the new schemes for sensitivity indices
of conditional expectations in some cases outperformed the ones proposed
previously, and variances of some estimators significantly depended on the
simulation method being applied.


title: Uniform measures and uniform rectifiability

abstract:
  In this paper it is shown that if $\mu$ is an n-dimensional Ahlfors-David
regular measure in $R^d$ which satisfies the so-called weak constant density
condition, then $\mu$ is uniformly rectifiable. This had already been proved by
David and Semmes in the cases n=1, 2 and d-1, and it was an open problem for
other values of n. The proof of this result relies on the study of the
n-uniform measures in $R^d$. In particular, it is shown here that they satisfy
the "big pieces of Lipschitz graphs" property.


title:
Soft x-rays absorption and high-resolution powder x-ray diffraction
  study of superconducting CaxLa(1-x)Ba(1.75-x)La(0.25+x)Cu3Oy system

abstract:
  We have studied the electronic structure of unoccupied states measured by O
K-edge and Cu L-edge x-ray absorption spectroscopy (XAS), combined with crystal
structure studied by high resolution powder x-ray diffraction (HRPXRD), of
charge-compensated layered superconducting CaxLa(1-x)Ba(1.75-x)La(0.25+x)Cu3Oy
(0<x<0.4, 6.4<y<7.3) cuprate. A detailed analysis shows that, apart from hole
doping, chemical pressure on the electronically active CuO2 plane due to the
lattice mismatch with the spacer layers greatly influences the superconducting
properties of this system. The results suggest chemical pressure to be the most
plausible parameter to control the maximum critical temperatures (Tcmax) in
different cuprate families at optimum hole density.


title: Overview on Low-flux Detectors

abstract:
  Laboratory based searches for weakly-interacting slim particles (WISPs) of
the light-shining-through-a-wall type (LSW) use visible or near-infrared (NIR)
laser light. Low-noise and highly efficient detectors are necessary to improve
over previous experiments. These requirements overlap with the requirements for
single-photon detectors (SPDs) for quantum information (QI) experiments. In
this contribution, the sensitivity of several QI SPDs is compared to
photo-multiplier tubes (PMTs) and imaging charge-coupled devices (CCDs). It is
found that only transition edge sensors (TESs) are viable alternatives to CCDs
if the signal can be focussed to a few micro meters.


title:
The Whetstone and the Alum Block: Balanced Objective Bayesian Comparison
  of Nested Models for Discrete Data

abstract:
  When two nested models are compared, using a Bayes factor, from an objective
standpoint, two seemingly conflicting issues emerge at the time of choosing
parameter priors under the two models. On the one hand, for moderate sample
sizes, the evidence in favor of the smaller model can be inflated by
diffuseness of the prior under the larger model. On the other hand,
asymptotically, the evidence in favor of the smaller model typically
accumulates at a slower rate. With reference to finitely discrete data models,
we show that these two issues can be dealt with jointly, by combining intrinsic
priors and nonlocal priors in a new unified class of priors. We illustrate our
ideas in a running Bernoulli example, then we apply them to test the equality
of two proportions, and finally we deal with the more general case of logistic
regression models.


title: High Precision DIS 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. 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 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:
Fragility and molar volumes of non-stoichiometric chalcogenides -- the
  crucial role of melt/glass homogenization

abstract:
  Melt-fragility index (m) and glass molar volumes (Vm) of binary Ge-Se
melts/glasses are found to change reproducibly as they are homogenized.
Variance of Vm decreases as glasses homogenize, and the mean value of Vm
increases to saturate at values characteristic of homogeneous glasses. Variance
in fragility index of melts also decreases as they are homogenized, and the
mean value of m decreases to acquire values characteristic of homogeneous
melts. Broad consequences of these observations on physical behavior of
chalcogenides melts/glasses are commented upon. The intrinsically slow kinetics
of melt homogenization derives from high viscosity of select super-strong melt
compositions in the Intermediate Phase that serve to bottleneck atomic
diffusion at high temperatures.


title:
Magnetic fields of Ap stars from the full Stokes spectropolarimetric
  observations

abstract:
  Current knowledge about stellar magnetic fields relies almost entirely on
circular polarization observations. Few objects have been observed in all four
Stokes parameters. The magnetic Ap star HD 24712 (DO Eri, HR 1217) was recently
observed in the Stokes IQUV parameters with the HARPSpol instrument at the
3.6-m ESO telescope as part of our project at investigating Ap stars in all
four Stokes parameters. The resulting spectra have dense phase coverage,
resolving power > 10^5, and S/N ratio of 300-600. These are the highest quality
full Stokes observations obtained for any star other than the Sun.
  We present preliminary results from magnetic Doppler imaging of HD 24712.
This analysis is the first step towards obtaining detailed 3-D maps of magnetic
fields and abundance structures for HD 24712 and other Ap stars that we
currently observe with HARPSpol.


title: Protected nodes and fringe subtrees in some random trees

abstract:
  We study protected nodes in various classes of random rooted trees by putting
them in the general context of fringe subtrees introduced by Aldous (1991).
Several types of random trees are considered: simply generated trees (or
conditioned Galton-Watson trees), which includes several cases treated
separately by other authors, binary search trees and random recursive trees.
This gives unified and simple proofs of several earlier results, as well as new
results.


title:
Skyrmion confinement in ultrathin film nanostructures in the presence of
  Dzyaloshinskii-Moriya interaction

abstract:
  We study the modification of micromagnetic configurations in nanostructures,
due to the Dzyaloshinskii-Moriya interaction (DMI) that appear at the interface
of an ultrathin film. We show that this interaction leads to new micromagnetic
boundary conditions that bend the magnetization at the edges. We explore
several cases of ultrathin film nanostructures that allow analytical
calculations (1D systems, domain walls, cycloids and skyrmions), compare with
fully numerical calculations, and show that a good physical understanding of
this new type of micromagnetics can be reached. We particularly focus on
skyrmions confined in circular nanodots and show that edges allow for the
isolation of single skyrmions for a large range of the DMI parameter.


title: A confined flare above filaments

abstract:
  We present the dynamics of two filaments and a C-class flare observed in NOAA
11589 on 2012 October 16. We used the multi-wavelength high-resolution data
from SDO, as well as THEMIS and ARIES ground-based observations. The
observations show that the filaments are progressively converging towards each
other without merging. We find that the filaments have opposite chirality which
may have prevented them from merging. On October 16, a C3.3 class flare
occurred without the eruption of the filaments. According to the standard solar
flare model, after the reconnection, post-flare loops form {\it below} the
erupting filaments whether the eruption fails or not. However, the observations
show the formation of post-flare loops {\it above} the filaments, which is not
consistent with the standard flare model. We analyze the topology of the active
region's magnetic field by computing the quasi-separatrix layers (QSLs) using a
linear force-free field extrapolation. We find a good agreement between the
photospheric footprints of the QSLs and the flare ribbons. We discuss how
slipping or slip-running reconnection at the QSLs may explain the observed
dynamics.


title: Simulating Bell violations without quantum computers

abstract:
  We demonstrate that it is possible to simulate Bell violations using
probabilistic methods. A quantum state corresponding to optical experiments
that violate the Bell inequality is generated, demonstrating that these quantum
paradoxes can indeed be simulated probabilistically. This provides an explicit
counter-example to Feynman's claim that such classical simulations could not be
carried out.


title:
Excitonic Instability at the Spin-State Transition in the Two-Band
  Hubbard Model

abstract:
  Using linear response theory with the dynamical mean-field approximation we
investigate the particle-hole instabilities of the two-band Hubbard model in
the vicinity of the spin-state transition. Besides the previously reported
high-spin--low-spin order we find an instability towards triplet excitonic
condensate. We discuss the strong and weak coupling limits of the model, in
particular, a connection to the spinful hard-core bosons with a
nearest-neighbor interaction. Possible realization in LaCoO3 at intermediate
temperatures is briefly discussed.


title: A Uniquely Ergodic Cellular Automaton

abstract:
  We construct a one-dimensional uniquely ergodic cellular automaton which is
not nilpotent. This automaton can perform asymptotically infinitely sparse
computation, which nevertheless never disappears completely. The construction
builds on the self-simulating automaton of G\'acs. We also prove related
results of dynamical and computational nature, including the undecidability of
unique ergodicity, and the undecidability of nilpotency in uniquely ergodic
cellular automata.


title: Self-similarity in jet events following from p-p collisions at LHC

abstract:
  Using a Tsallis nonextensive approach, we simultaneously analyze recent data
obtained by the LHC ATLAS experiment on distributions of transverse momenta of
jets, p_T^{jet}, together with distributions of transverse momenta of particles
produced within these jets (defined relative to the jet's axis), p_T^{rel}, and
their multiplicity distributions, P(N). The respective nonextensivity
parameters for distributions of jets, q_{jet}, for distributions of particles
in jets, q_{rel} and the global nonextensivity parameter obtained from P(N),
q_N, were then compared with nonextensivity parameters q obtained from minimum
bias pp collisions at energies corresponding to the energies of these jets. The
values of the corresponding nonextensivity parameters were found to be similar,
strongly indicating the existence of a common mechanism behind all these
processes. We tentatively identify this as a self-similarity property known to
be present there and resulting in Tsallis type distributions. If confirmed,
this would considerably strengthen the nonextensive Tsallis approach.


title:
Fractional Fourier detection of L\'evy Flights: application to
  Hamiltonian chaotic trajectories

abstract:
  A signal processing method designed for the detection of linear (coherent)
behaviors among random fluctuations is presented. It is dedicated to the study
of data recorded from nonlinear physical systems. More precisely the method is
suited for signals having chaotic variations and sporadically appearing regular
linear patterns, possibly impaired by noise. We use time-frequency techniques
and the Fractional Fourier transform in order to make it robust and easily
implementable. The method is illustrated with an example of application: the
analysis of chaotic trajectories of advected passive particles. The signal has
a chaotic behavior and encounter L\'evy flights (straight lines). The method is
able to detect and quantify these ballistic transport regions, even in noisy
situations.


title: Constraint on Light Dipole Dark Matter from Helioseismology

abstract:
  We investigate the effects of a magnetic dipole moment of asymmetric dark
matter (DM) in the evolution of the Sun. The dipole interaction can lead to a
sizable DM scattering cross section even for light DM, and the asymmetric dark
matter can lead to a large DM number density in the Sun. We find that solar
model precision tests, using as diagnostic the sound speed profile obtained
from helioseismology data, exclude dipolar dark matter particles with a mass
larger than 4.3 GeV and magnetic dipole moment larger than 1.6 $\times
\;10^{-17}$ e cm.


title: Theory of second harmonic generation in few-layered MoS2

abstract:
  Recent experimental results have demonstrated the ability of monolayer
MoS$_2$ to efficiently generate second harmonic fields with susceptibilities
between 0.1 and 100 nm/V. However, no theoretical calculations exist with which
to interpret these findings. In particular, it is of interest to theoretically
estimate the modulus of the second harmonic response, since experimental
reports on this differ by almost three orders of magnitude. Here, we present
single-particle calculations of the second harmonic response based on a
tight-binding band structure. We compare directly with recent experimental
findings and include in the discussion also spectral features and the effects
of multiple layers.


title:
Can a non-local model of gravity reproduce Dark Matter effects in
  agreement with MOND?

abstract:
  I analyze the possibility of reproducing MONDian Dark Matter effects by using
a non-local model of gravity. The model was used before in order to recreate
screening effects for the Cosmological Constant ($\Lambda$) value. Although the
model in the weak-field approximation (in static coordinates) can reproduce the
field equations in agreement with the AQUAL Lagrangian, the solutions are scale
dependent and cannot reproduce the same dynamics in agreement with MOND.


title:
A normalized scaled gradient method to solve non-negativity and equality
  constrained linear inverse problem - Application to spectral mixture analysis

abstract:
  This paper addresses the problem of minimizing a convex cost function under
non-negativity and equality constraints, with the aim of solving the linear
unmixing problem encountered in hyperspectral imagery. This problem can be
formulated as a linear regression problem whose regression coefficients
(abundances) satisfy sum-to-one and positivity constraints. A normalized scaled
gradient iterative method (NSGM) is proposed for estimating the abundances of
the linear mixing model. The positivity constraint is ensured by the Karush
Kuhn Tucker conditions whereas the sum-to-one constraint is fulfilled by
introducing normalized variables in the algorithm. The convergence is ensured
by a one-dimensional search of the step size. Note that NSGM can be applied to
any convex cost function with non negativity and flux constraints. In order to
compare the NSGM with the well-known fully constraint least squares (FCLS)
algorithm, this latter is reformulated in term of a penalized function, which
reveals its suboptimality. Simulations on synthetic data illustrate the
performances of the proposed algorithm in comparison with other unmixing
algorithms and, more particulary, demonstrate its efficiency when compared to
the popular FCLS. Finally, results on real data are given.


title: DVB-S2 Spectrum Efficiency Improvement with Hierarchical Modulation

abstract:
  We study the design of a DVB-S2 system in order to maximise spectrum
efficiency. This task is usually challenging due to channel variability. Modern
satellite communications systems such as DVB-SH and DVB-S2 rely mainly on a
time sharing strategy to optimise the spectrum efficiency. Recently, we showed
that combining time sharing with hierarchical modulation can provide
significant gains (in terms of spectrum efficiency) compared to the best time
sharing strategy. However, our previous design does not improve the DVB-S2
performance when all the receivers experience low or large signal-to-noise
ratios. In this article, we introduce and study a hierarchical QPSK and a
hierarchical 32-APSK to overcome the previous limitations.We show in a
realistic case based on DVB-S2 that the hierarchical QPSK provides an
improvement when the receivers experience poor channel condition, while the
32-APSK increases the spectrum efficiency when the receivers experience good
channel condition.


title:
The Stone-Cech compactifications of $\omega^*\setminus \{x\}$ and
  $S_\kappa\setminus\{x\}$

abstract:
  The space $S_\kappa$ is the Stone space of the $\kappa$-saturated Boolean
algebra of cardinality $\kappa$. It exists provided that $\kappa =
\kappa^{<\kappa}$, and is characterised topologically as the unique
$\kappa$-Parovichenko space of weight $\kappa$. Under the Continuum Hypothesis,
$S_{\omega_1}$ coincides with $\omega^*$. This paper investigates questions
related to the Stone-Cech compactification of spaces $S_\kappa \setminus
\{x\}$, extending corresponding results obtained by Fine & Gillman and Comfort
& Negrepontis for the space $\omega^*$.
  We show that for every point $x$ of $S_\kappa$, the Stone-Cech remainder of
$S_\kappa \setminus \{x\}$ is a $\kappa^+$-Parovichenko space of cardinality
$2^{2^\kappa}$ which admits a family of $2^\kappa$ disjoint clopen sets. As a
corollary we get that it is consistent with CH that the Stone-Cech remainders
of $\omega^* \setminus \{x\}$ are all homeomorphic.


title:
Multiple solutions for p-Laplacian type problems with asymptotically
  p-linear terms via a cohomological index theory

abstract:
  The aim of this paper is investigating the existence of weak solutions of the
quasilinear elliptic model problem \[ \left\{\begin{array}{lr} - \divg
(A(x,u)\, |\nabla u|^{p-2}\, \nabla u) + \dfrac1p\, A_t(x,u)\, |\nabla u|^p\ =\
f(x,u) & \hbox{in $\Omega$,}\\ u\ = \ 0 & \hbox{on $\partial\Omega$,}
\end{array} \right. \] where $\Omega \subset \R^N$ is a bounded domain, $N\ge
2$, $p > 1$, $A$ is a given function which admits partial derivative $A_t(x,t)
= \frac{\partial A}{\partial t}(x,t)$ and $f$ is asymptotically $p$-linear at
infinity.
  Under suitable hypotheses both at the origin and at infinity, and if
$A(x,\cdot)$ is even while $f(x,\cdot)$ is odd, by using variational tools, a
cohomological index theory and a related pseudo--index argument, we prove a
multiplicity result if $p > N$ in the non--resonant case.


title: Characteristic ideals and Iwasawa theory

abstract:
  Let $\L$ be a non-noetherian Krull domain which is the inverse limit of
noetherian Krull domains $\L_d$ and let $M$ be a finitely generated $\L$-module
which is the inverse limit of $\L_d$-modules $M_d\,$. Under certain hypotheses
on the rings $\L_d$ and on the modules $M_d\,$, we define a pro-characteristic
ideal for $M$ in $\L$, which should play the role of the usual characteristic
ideals for finitely generated modules over noetherian Krull domains. We apply
this to the study of Iwasawa modules (in particular of class groups) in a
non-noetherian Iwasawa algebra $\Z_p[[\Gal(\calf/F)]]$, where $F$ is a function
field of characteristic $p$ and $\Gal(\calf/F)\simeq\Z_p^\infty$.


title: Fuzzy Gamma-hypersemigroups

abstract:
  We introduced and study fuzzy gamma-hypersemigroups, according to fuzzy
semihyper- groups as previously defined [33] and prove that results in this
respect. In this regard first we introduce fuzzy hyperoperation and then study
fuzzy gamma-hypersemigroup. We will proceed by study fuzzy gamma-hyperideals
and fuzzy gamma-bihyperideals. Also we study the relation between the classes
of fuzzy gamma-hypersemigroups and semigroups. Precisely, we associate a
gamma-hypersemigroup to every fuzzy hypersemigroup and vice versa. Finally, we
introduce and study fuzzy hypersemigroups regular and fuzzy strongly regular
relations of fuzzy gamma-hypersemigroups regular and fuzzy strongly regular
relations of fuzzy gamma-hypersemigroups.


title:
Determination of boson spectrum from optical data in pseudogap phase of
  underdoped cuprates

abstract:
  Information on the nature of the dominant inelastic processes operative in
correlated metallic systems can be obtained from an analysis of their AC
optical response. An electron-boson spectral density can usefully be extracted.
This density is closely related to the optical scattering rate. However, in the
underdoped region of the high Tc cuprate phase diagram a new energy scale (the
pseudogap) emerges, which alters the optical scattering and needs to be taken
into account in any fit to data. This can influence the shape and strength of
the recovered boson spectral function. Including a pseudogap in an extended
maximum entropy inversion for optimally doped Bi-2212 is more consistent with
existing data than when it is left out as done previously.


title: Quantum heat engines and refrigerators: Continuous devices

abstract:
  Quantum thermodynamics supplies a consistent description of quantum heat
engines and refrigerators up to the level of a single few level system coupled
to the environment. Once the environment is split into three;a hot, cold and
work reservoirs a heat engine can operate. The device converts the positive
gain into power;where the gain is obtained from population inversion between
the components of the device. Reversing the operation transforms the device
into a quantum refrigerator. The quantum tricycle, a device connected by three
external leads to three heat reservoirs is used as a template for engines and
refrigerators. The equation of motion for the heat currents and power can be
derived from first principle. Only a global description of the coupling of the
device to the reservoirs is consistent with the first and second laws of
thermodynamics. Optimisation of the devices leads to a balanced set of
parameters where the couplings to the three reservoirs are of the same order
and the external driving field is in resonance. When analysing refrigerators
special attention is devoted to a dynamical version of the third law of
thermodynamics. Bounds on the rate of cooling when approaching the absolute
zero are obtained by optimising the cooling current. At low temperature all
refrigerators show universal behavior. Restrictions on the system imposed by
the dynamical version of the third law are studied.


title:
Chemical constraints on the contribution of Population III stars to
  cosmic reionization

abstract:
  Recent studies have highlighted that galaxies at z = 6-8 fall short of
producing enough ionizing photons to reionize the IGM, and suggest that
Population III stars could resolve this tension, because their harder spectra
can produce ~10x more ionizing photons than Population II. But this argument
depends critically on the duration of the Population III era, and because
Population III stars form from pristine gas, in turn depends on the rate of
galactic enrichment. We use a semi-analytic model of galaxy formation which
tracks galactic chemical evolution, to gauge the impact of Population III stars
on reionization. Population III SNe produce distinct metal abundances, and we
argue that the duration of the Population III era can be constrained by precise
relative abundance measurements in high-z damped Ly{\alpha} absorbers (DLAs),
which provide a chemical record of past star-formation. We find that a single
generation of Population III stars can self-enrich galaxies above the critical
metallicity Zcrit=10^-4 Zsun for the Population III-to-II transition, on a very
short timescale of ~10^6 yr, owing to the large metal yields and short
lifetimes of Population III stars. This subsequently terminates the Population
III era, hence they contribute >~ 50% of the ionizing photons only for z >~ 30,
and at z=10 contribute <1%. The Population III contribution can be increased by
delaying metal mixing into the ISM. However comparing the resulting metal
abundance pattern to existing measurements in z <~ 6 DLAs, we show that the
fractional contribution of high-mass Population III stars to the ionization
rate must be <~ 10% at z = 10. Future abundance measurements of z~7-8 QSOs and
GRBs should probe the era when the chemical vestiges of Population III star
formation become detectable.


title: Exciton condensation in strongly correlated electron bilayers

abstract:
  We studied the possibility of exciton condensation in Mott insulating
bilayers. In these strongly correlated systems an exciton is the bound state of
a double occupied and empty site. In the strong coupling limit the exciton acts
as a hard-core boson. Its physics are captured by the exciton t-J model,
containing an effective XXZ model describing the exciton dynamics only. Using
numerical simulations and analytical mean field theory we constructed the
ground state phase diagram. Three homogeneous phases can be distinguished: the
antiferromagnet, the exciton checkerboard crystal and the exciton superfluid.
For most model parameters, however, we predict macroscopic phase separation
between these phases. The exciton superfluid exists only for large exciton
hopping energy. Additionally we studied the collective modes and
susceptibilities of the three phases. In the superfluid phase we find the
striking feature that the bandwidth of the spin-triplet excitations,
potentially detectable by resonant inelastic x-ray scattering (RIXS), is
proportional to the superfluid density. The superfluid phase mode is visible in
the charge susceptibility, measurable by RIXS or electron energy loss
spectroscopy (EELS).


title:
Formal analogy between the Dirac equation in its Majorana form and the
  discrete-velocity version of the Boltzmann kinetic equation

abstract:
  We point out a formal analogy between the Dirac equation in Majorana form and
the discrete-velocity version of the Boltzmann kinetic equation. By a
systematic analysis based on the theory of operator splitting, this analogy is
shown to turn into a concrete and efficient computational method, providing a
unified treatment of relativistic and non-relativistic quantum mechanics. This
might have potentially far-reaching implications for both classical and quantum
computing, because it shows that, by splitting time along the three spatial
directions, quantum information (Dirac-Majorana wavefunction) propagates in
space-time as a classical statistical process (Boltzmann distribution).


title:
Near-infrared studies of glucose and sucrose in aqueous solutions: water
  displacement effect and red shift in water absorption from water-solute
  interaction

abstract:
  We use near infrared spectroscopy to obtain concentration dependent glucose
absorption spectra in their aqueous solutions in the near-infrared range (3800
- 7500 cm^{-1}). We introduce a new method to obtain reliable glucose
absorption bands from aqueous glucose solutions without measuring the water
displacement coefficients of glucose separately. Additionally, we are able to
extract the water displacement coefficients of glucose, and this may give a new
general method using spectroscopy techniques applicable to other water soluble
materials. We also observe red shifts in the absorption bands of water in the
hydration shell around solute molecules, which comes from contribution of the
interacting water molecules around the glucose molecules in solutions. The
intensity of the red shift get larger as the concentration increases, which
indicates that as the concentration increases more water molecules are involved
in the interaction. However, the red shift in frequency does not seem to depend
significantly on the concentration up to our highest concentration. We also
performed the same measurements and analysis with sucrose instead of glucose as
solute and compare.


title:
Effects of a temperature dependent viscosity on thermal convection in
  binary mixtures

abstract:
  We investigate the effect of a temperature dependent viscosity on the onset
of thermal convection in a horizontal layer of a binary fluid mixture that is
heated from below. For an exponential temperature dependence of the viscosity,
we find in binary mixtures as a function of a positive separation ratio and
beyond a certain viscosity contrast a discontinuous transition between two
stationary convection modes having a different wavelength. In the range of
negative values of the separation ratio, a (continuous or discontinuous)
transition from an oscillatory to a stationary onset of convection occurs
beyond a certain viscosity contrast, and for large values of the viscosity
ratio, the oscillatory onset of convection is suppressed.


title:
Approximate solution of inverse boundary problem for the heat exchange
  problem by A.N. Tikhonov regularization method

abstract:
  In this paper the approximate solution of the heat exchange problem by A.N.
Tikhonov regularization method is presented. The errror estimation of this
approximate is obtained.


title: Horizontal Visibility graphs generated by type-II intermittency

abstract:
  In this contribution we study the onset of chaos via type-II intermittency
within the framework of Horizontal Visibility graph theory. We construct graphs
associated to time series generated by an iterated map close to a
Neimark-Sacker bifurcation and study, both numerically and analytically, their
main topological properties. We find well defined equivalences between the main
statistical properties of intermittent series (scaling of laminar trends and
Lyapunov exponent) and those of the resulting graphs, and accordingly construct
a graph theoretical description of type-II intermittency. We finally recast
this theory into a graph-theoretical renormalization group framework, and show
that the fixed point structure of RG flow diagram separates regular, critical
and chaotic dynamics.


title:
Fractional charges in emergent neutral modes at the integer quantum Hall
  effect

abstract:
  Charge fractionalization is a possible emergent excitation in a
low-dimensional system of interacting electrons. A known example is that of
fractional charges in the fractional quantum Hall effect (FQHE) regime, which
is a consequence of strong Coulomb interaction among the electrons whose
kinetic energy is quenched by the strong magnetic field. Alternatively, the
integer QHE (IQHE), with electrons behaving largely as independent particles in
Landau levels (LLs), lacks such fractionalization. However, for integer LLs
filling v=2, 3,... electrons propagate in copropagating adjacent chiral edge
channels, and thus interact and modify the non-interacting LLs. For example, at
v=2, an electron injected selectively into a single non-interacting (bare) edge
channel is expected to decompose into a 'fast' mode and a 'slow' mode in the
region of interaction; each mode carry fractional charges shared between the
two bare channels. Here, we report our sensitive shot noise measurement that
affirms the presence of such fractionalization in v=2. Injecting partitioned
current into a 'hot' edge channel led to low frequency shot noise in the
adjacent currentless 'cold' edge channel after it had been partitioned.
Controlling the partitioning of the hot and cold channels allowed a
determination of the fractional charges in both channels as well as the
channels' velocity difference. This approach can be easily extended to study
interaction in two-dimensional systems with a topology dictating edge channels
transport.


title:
Evolution of electron-boson spectral density in the underdoped region of
  Bi_2Sr_{2-x}La_xCuO_6

abstract:
  We use a maximum entropy technique to obtain the electron-boson spectral
density from optical scattering rate data across the underdoped region of the
Bi_2Sr_{2-x}La_xCuO_6 (Bi-2201) phase diagram. Our method involves a
generalization of previous work which explicitly include finite temperature and
the opening of a pseudogap which modifies the electronic structure. We find
that the mass enhancement factor \lambda associated with the electron-boson
spectral density increases monotonically with reduced doping and closer
proximity to the Mott antiferromagnetic insulating state. This observation is
consistent with increased coupling to the spin fluctuations. At the same time
the system has reduced metallicity because of increased pseudogap effects which
we model with a reduced effective density of states around the Fermi energy
with the range of the modifications in energy set by the pseudogap scale.


title: Constraining f(R) gravity with PLANCK data on galaxy cluster profiles

abstract:
  Models of $f(R)$ gravity that introduce corrections to the Newtonian
potential in the weak field limit are tested at the scale of galaxy clusters.
These models can explain the dynamics of spiral and elliptical galaxies without
resorting to dark matter. We compute the pressure profiles of 579 galaxy
clusters assuming that the gas is in hydrostatic equilibrium within the
potential well of the modified gravitational field. The predicted profiles are
compared with the average profile obtained by stacking the data of our cluster
sample in the Planck foreground clean map SMICA. We find that the resulting
profiles of these systems fit the data without requiring a dominant dark matter
component, with model parameters similar to those required to explain the
dynamics of galaxies. Our results do not rule out that clusters are dynamically
dominated by Dark Matter but support the idea that Extended Theories of Gravity
could provide an explanation to the dynamics of self-gravitating systems and to
the present period of accelerated expansion, alternative to the concordance
cosmological model.


title: Elimination of the A-square problem from cavity QED

abstract:
  We generalize the Power-Zineau-Woolley transformation to obtain a canonical
Hamiltonian of cavity quantum electrodynamics for arbitrary geometry of
boundaries. This Hamiltonian is free from the A-square term and the
instantaneous Coulomb interaction between distinct atoms. The single-mode
models of cavity QED (Dicke, Tavis-Cummings, Jaynes-Cummings) are justified by
a term by term mapping to the proposed microscopic Hamiltonian. As one
straightforward consequence, the basis of no-go argumentations concerning the
Dicke phase transition with atoms in electromagnetic fields dissolves.


title:
Resilience of helical fields to turbulent diffusion II: direct numerical
  simulations

abstract:
  The recent study of Blackman and Subramanian (Paper I) indicates that large
scale helical magnetic fields are resilient to turbulent diffusion in the sense
that helical fields stronger than a critical value, decay on slow (~resistively
mediated), rather than fast ($\sim$ turbulent) time scales. This gives more
credence to potential fossil field origin models of the magnetic fields in
stars, galaxies and compact objects. We analyze a suite of direct numerical
simulations (DNS) of decaying large scale helical magnetic fields in the
presence of non-helical turbulence to further study the physics of helical
field decay. We study two separate cases: (1) the initial field is large enough
to decay resistively, is tracked until it transitions to decay fast, and the
critical large scale helical field at that transition is sought; (2) the case
of Paper I, wherein there is a critical initial helical field strength below
which the field undergoes fast decay right from the beginning. In case (1),
both DNS and solutions of the two scale model (from Paper 1), reveal that the
transition energy, $E_{c1}$, is independent of the scale of the turbulent
forcing, within a small range of $\Rm$. We also find that the kinetic alpha,
$\alpha_K$, is subdominant to magnetic alpha, $\alpha_M$, in the DNS,
justifying an assumption in the two scale model. For case (2), we show exact
solutions of two scale model in the limit of $\eta \rightarrow 0$ in fully
helical case, leading to the transition energy, $E_{c2} = (k_1/\kf)^2 M_{eq}$,
where $k_1$ and $\kf$ are the large scale and small turbulent forcing scale
respectively and $M_{eq}$ is the equipartition magnetic energy. The DNS in this
case agree qualitatively with the two scale model but the $R_M$ currently
achievable, is too small to satisfy a condition $3/R_M << (k_1/k_f)^2$,
necessary to robustly reveal the transition, $E_{c2}$ (Abridged).

categories: astro-ph.GA astro-ph.HE astro-ph.SR physics.plasm-ph


title: The PLATO 2.0 Mission

abstract:
  PLATO 2.0 has recently been selected for ESA's M3 launch opportunity
(2022/24). Providing accurate key planet parameters (radius, mass, density and
age) in statistical numbers, it addresses fundamental questions such as: How do
planetary systems form and evolve? Are there other systems with planets like
ours, including potentially habitable planets? The PLATO 2.0 instrument
consists of 34 small aperture telescopes (32 with 25 sec readout cadence and 2
with 2.5 sec candence) providing a wide field-of-view (2232 deg2) and a large
photometric magnitude range (4-16 mag). It focusses on bright (4-11 mag) stars
in wide fields to detect and characterize planets down to Earth-size by
photometric transits, whose masses can then be determined by ground-based
radial-velocity follow-up measurements. Asteroseismology will be performed for
these bright stars to obtain highly accurate stellar parameters, including
masses and ages. The combination of bright targets and asteroseismology results
in high accuracy for the bulk planet parameters: 2%, 4-10% and 10% for planet
radii, masses and ages, respectively. The planned baseline observing strategy
includes two long pointings (2-3 years) to detect and bulk characterize planets
reaching into the habitable zone (HZ) of solar-like stars and an additional
step-and-stare phase to cover in total about 50% of the sky. PLATO 2.0 will
observe up to 1,000,000 stars and detect and characterize hundreds of small
planets, and thousands of planets in the Neptune to gas giant regime out to the
HZ. It will therefore provide the first large-scale catalogue of bulk
characterized planets with accurate radii, masses, mean densities and ages.
This catalogue will include terrestrial planets at intermediate orbital
distances, where surface temperatures are moderate. Coverage of this parameter
range with statistical numbers of bulk characterized planets is unique to PLATO
2.0.


title: Possible consistent extra time dimensions in the early universe

abstract:
  Gravity cannot be quantized unless the quantized theory is cast on a manifold
whose concomitant number of physical space dimensions and number of physical
time dimensions correspond to physical reality, and not simply to the
perception of reality. At present, the accepted number of physical time
dimensions is dictated more by folklore than by science. In this paper we
discuss a model of the early universe in which the number of physical time
dimensions is four, and formulate Theorem[\ref{tj}], which underlies an
explanation of why the extra time dimensions do not source unphysical effects.
  In this paper we describe a new model of gravitational inflation that is
driven by dark energy and "mediated" by a real massless scalar inflaton field
$\varphi$ whose potential is identically equal to zero. The coupled Einstein
gravitational and inflaton field equations are formulated on an
eight-dimensional spacetime manifold of \textbf{four space} dimensions and
\textbf{four time} dimensions. We find explicit solutions to these field
equations that exhibit temporal exponential \textbf{deflation of three of the
four time dimensions}, and then study the dynamics of a massive complex scalar
field $\psi$ that propagates on the background ground state Einstein
gravitational field to determine whether its quantum fluctuations $\delta \psi$
are stable or unstable. We compute explicit approximate solutions to the
$\delta \psi$ field equations that are \textbf{stable}, meaning that the
quantum fluctuations $\delta \psi$ of the field $\psi$ do not grow
exponentially with time. \textbf{Instabilities} driven by the momenta
associated to the three extra time dimensions do not appear in the physical
solutions of the field equations of this model.


title:
Simulation of a hump structure in the optical scattering rate within a
  generalized Allen formalism and its application to copper oxide systems

abstract:
  We propose a possible way to simulate a hump structure in the optical
scattering rate. The optical scattering rate of correlated charge carriers can
be defined within an extended Drude model formalism. When some electron and
hole doped copper oxide systems are in the spin density or charge density wave
phases they show hump structures in their optical scattering rates. The hump
structures have not yet been simulated and understood clearly. We are able to
simulate the hump structure by using a peak followed by a dip feature in the
normalized density of states within a generalized Allen formalism. We observe
that reversing the order of the dip and peak gives completely different
features in the optical scattering rate; a peak-dip (dip peak) results in a
hump (a valley) in the scattering rate. We also obtain the real part of the
optical conductivity and reflectance spectra from the simulated optical
scattering rate and compare them with published experimental spectra. From
these comparisons we conclude that the peak-dip order can give the hump
structure, which is observed experimentally in copper oxide systems. Finally we
fit two published optical spectra with our new model and discuss our results
and the possible origin of the dip or peak features in the normalized density
of states.


title:
Modified $(G'/G)$-expansion method for solving nonlinear partial
  differential equations

abstract:
  This paper addresses a modified ($G'/G$)-expansion method to obtain new
classes of solutions to nonlinear partial differential equations (NPDEs). The
cases of Burgers, KdV and Kadomtsev-Petviashvili NPDEs are exhaustively
studied. Relevant graphical representations are shown in each case.


title: Combinatorial symmetry of line arrangements and applications

abstract:
  We introduce an algorithm that exploits a combinatorial symmetry of an
arrangement in order to produce a geometric reflection between two disconnected
components of its moduli space. We apply this method to disqualify three real
examples found in previous work by the authors from being Zariski pairs.
Robustness is shown by its application to complex cases, as well.


title: On L\'evy's Brownian motion indexed by the elements of compact groups

abstract:
  We investigate positive definiteness of the Brownian kernel
K(x,y)=1/2(d(x,x_0) + d(y,x_0) - d(x,y)) on a compact group G and in particular
for G=SO(n).


title: Beam energy scan using a viscous hydro+cascade model

abstract:
  Following the experimental program at BNL RHIC, we perform a similar "energy
scan" using 3+1D viscous hydrodynamics coupled to the UrQMD hadron cascade, and
study the collision energy dependence of pion and kaon rapidity distributions
and $m_T$-spectra, as well as charged hadron elliptic flow. To this aim the
equation of state for finite baryon density from a Chiral model coupled to the
Polyakov loop is employed for hydrodynamic stage. 3D initial conditions from
UrQMD are used to study gradual deviation from boost-invariant scaling flow. We
find that the inclusion of shear viscosity in the hydrodynamic stage of
evolution consistently improves the description of the data for Pb-Pb
collisions at CERN SPS, as well as of the elliptic flow measurements for Au-Au
collisions in the Beam Energy Scan (BES) program at BNL RHIC. The suggested
value of shear viscosity is $\eta/s\ge0.2$ for $\sqrt{s_{NN}}=6.3\dots39$ GeV.


title: Monotonic cocycles

abstract:
  We develop a "local theory" of multidimensional quasiperiodic $\SL(2,\R)$
cocycles which are not homotopic to a constant. It describes a $C^1$-open
neighborhood of cocycles of rotations and applies irrespective of arithmetic
conditions on the frequency, being much more robust than the local theory of
$\SL(2,\R)$ cocycles homotopic to a constant. Our analysis is centered around
the notion of monotonicity with respect to some dynamical variable. For such
{\it monotonic cocycles}, we obtain a sharp rigidity result, minimality of the
projective action, typical nonuniform hyperbolicity, and a surprising result of
smoothness of the Lyapunov exponent (while no better than H\"older can be
obtained in the case of cocycles homotopic to a constant, and only under
arithmetic restrictions). Our work is based on complexification ideas, extended
"\`a la Lyubich" to the smooth setting (through the use of asymptotically
holomorphic extensions). We also develop a counterpart of this theory centered
around the notion of monotonicity with respect to a parameter variable, which
applies to the analysis of $\SL(2,\R)$ cocycles over more general dynamical
systems and generalizes key aspects of Kotani Theory. We conclude with a more
detailed discussion of one-dimensional monotonic cocycles, for which results
about rigidity and typical nonuniform hyperbolicity can be globalized using a
new result about convergence of renormalization.


title: The $L^2$ essential spectrum of the 2D Euler operator

abstract:
  Even in two dimensions, the spectrum of the linearized Euler operator is
notoriously hard to compute. In this paper we give a new geometric calculation
of the essential spectrum for 2D flows. This generalizes existing
results---which are only available when the flow has arbitrarily long periodic
orbits---and clarifies the role of individual streamlines in generating
essential spectra.


title: Gelfand spectra in Grothendieck toposes using geometric mathematics

abstract:
  In the (covariant) topos approach to quantum theory by Heunen, Landsman and
Spitters, one associates to each unital C*-algebra, A, a topos T(A) of sheaves
on a locale and a commutative C*-algebra, a, within that topos. The Gelfand
spectrum of a is a locale S in this topos, which is equivalent to a bundle over
the base locale. We further develop this external presentation of the locale S,
by noting that the construction of the Gelfand spectrum in a general topos can
be described using geometric logic. As a consequence, the spectrum, seen as a
bundle, is computed fibrewise.
  As a by-product of the geometricity of Gelfand spectra, we find an explicit
external description of the spectrum whenever the topos is a functor category.
As an intermediate result we show that locally perfect maps compose, so that
the externalization of a locally compact locale in a topos of sheaves over a
locally compact locale is locally compact, too.


title: Dirac oscillator and nonrelativistic Snyder-de Sitter algebra

abstract:
  Three dimensional Dirac oscillator was considered in deformed space obeyed to
deformed commutation relations known as Snyder-de Sitter algebra. Snyder-de
Sitter commutation relations gives rise to appearance minimal uncertainty in
position as well as in momentum. To derive energy spectrum and wavefunctions of
the Dirac oscillator supersymmetric quantum mechanics and shape invariance
technique was applied.


title: (Non)uniqueness of critical points in variational data assimilation

abstract:
  In this paper we apply the 4D-Var data assimilation scheme to the
initialization problem for a family of quasilinear evolution equations. The
resulting variational problem is non-convex, so it need not have a unique
minimizer. We comment on the implications of non-uniqueness in numerical
applications, then prove uniqueness results in the following situations: 1) the
observational times are all sufficiently small; 2) the prior covariance is
sufficiently small. We also give an example of a data set where the cost
functional has a critical point of arbitrarily large Morse index.


title:
On the characteristic of projectively invariant pseudo-distance on
  Finsler spaces

abstract:
  A projective parameter of a geodesic on a Finsler space is defined to be
solution of a certain ODE. Using projective parameter and Funk metric, one can
construct a projectively invariant intrinsic pseudo-distance on a Finsler
space. In the present work, solutions of the projective parameter's ODE are
characterized with respect to the sign of parallel Ricci tensor of a Finsler
space. It is shown that the pseudo-distance is trivial on complete Finsler
spaces of positive semi-definite Ricci tensor and it is a distance on Finsler
spaces of parallel negative definite Ricci tensor. These results generalize
some results of Kobayashi and Sasaki to Finsler geometry.


title:
Generalization of van Lambalgen's theorem and blind randomness for
  conditional probabilities

abstract:
  Generalization of the Lambalgen's theorem is studied with the notion of
Hippocratic (blind) randomness without assuming computability of conditional
probabilities. In [Bauwence 2014], a counter-example for the generalization of
Lambalgen's theorem is shown when the conditional probability is not
computable. In this paper, it is shown that (i) finiteness of martingale for
blind randomness, (ii) classification of two blind randomness by likelihood
ratio test, (iii) sufficient conditions for the generalization of the
Lambalgen's theorem, and (iv) an example that satisfies the Lambalgen's theorem
but the conditional probabilities are not computable for all random parameters.


title: Distributed computation of persistent homology

abstract:
  Persistent homology is a popular and powerful tool for capturing topological
features of data. Advances in algorithms for computing persistent homology have
reduced the computation time drastically -- as long as the algorithm does not
exhaust the available memory. Following up on a recently presented parallel
method for persistence computation on shared memory systems, we demonstrate
that a simple adaption of the standard reduction algorithm leads to a variant
for distributed systems. Our algorithmic design ensures that the data is
distributed over the nodes without redundancy; this permits the computation of
much larger instances than on a single machine. Moreover, we observe that the
parallelism at least compensates for the overhead caused by communication
between nodes, and often even speeds up the computation compared to sequential
and even parallel shared memory algorithms. In our experiments, we were able to
compute the persistent homology of filtrations with more than a billion (10^9)
elements within seconds on a cluster with 32 nodes using less than 10GB of
memory per node.