title:
Combining Dynamic Predictions from Joint Models for Longitudinal and
  Time-to-Event Data using Bayesian Model Averaging

abstract:
  The joint modeling of longitudinal and time-to-event data is an active area
of statistics research that has received a lot of attention in the recent
years. More recently, a new and attractive application of this type of models
has been to obtain individualized predictions of survival probabilities and/or
of future longitudinal responses. The advantageous feature of these predictions
is that they are dynamically updated as extra longitudinal responses are
collected for the subjects of interest, providing real time risk assessment
using all recorded information. The aim of this paper is two-fold. First, to
highlight the importance of modeling the association structure between the
longitudinal and event time responses that can greatly influence the derived
predictions, and second, to illustrate how we can improve the accuracy of the
derived predictions by suitably combining joint models with different
association structures. The second goal is achieved using Bayesian model
averaging, which, in this setting, has the very intriguing feature that the
model weights are not fixed but they are rather subject- and time-dependent,
implying that at different follow-up times predictions for the same subject may
be based on different models.


title: Memory of Quark Matter Card Game

abstract:
  Scientists at the Relativistic Heavy Ion Collider (RHIC, BNL) recently
discovered, that the hottest known form of matter is not a gas, but acts like a
fluid. Furthermore, this fluid of quarks expands and flows much more perfectly
than water or any other well known fluid. This aspect of the RHIC discovery can
be introduced even to primary levels of physics education, noting that the
usual solid to liquid to gas sequence of phase transitions now are known to be
followed by a transition to a nearly perfect fluid, a liquid of quarks, at the
largest temperatures made by humans. The educational games described herein
were invented by middle school students, members of a Science Club in Hungary.
The games were invented for their entertainment, the educational applications
in teaching high energy particle and nuclear physics to laypersons are quite
unexpected but most welcomed. This manuscript describes games with a deck of
cards called Quark Matter cards, where each card represents an elementary
particle. The games include an important contribution by Angela Melocoton, an
administrator of the Guests, Users and Visitors (GUV) Center at BNL. It
describes in simple terms, how to play the Memory of Quark Matter style card
games.

categories: physics.pop-ph hep-ex hep-ph nucl-ex physics.ed-ph


title: Spectral Compressive Sensing with Polar Interpolation

abstract:
  Existing approaches to compressive sensing of frequency-sparse signals
focuses on signal recovery rather than spectral estimation. Furthermore, the
recovery performance is limited by the coherence of the required sparsity
dictionaries and by the discretization of the frequency parameter space. In
this paper, we introduce a greedy recovery algorithm that leverages a
band-exclusion function and a polar interpolation function to address these two
issues in spectral compressive sensing. Our algorithm is geared towards line
spectral estimation from compressive measurements and outperforms most existing
approaches in fidelity and tolerance to noise.


title: Universally optimal crossover designs under subject dropout

abstract:
  Subject dropout is very common in practical applications of crossover
designs. However, there is very limited design literature taking this into
account. Optimality results have not yet been well established due to the
complexity of the problem. This paper establishes feasible, as well as
necessary and sufficient conditions for a crossover design to be universally
optimal in approximate design theory in the presence of subject dropout. These
conditions are essentially linear equations with respect to proportions of all
possible treatment sequences being applied to subjects and hence they can be
easily solved. A general algorithm is proposed to derive exact designs which
are shown to be efficient and robust.


title: Valence Fluctuation in CeMo2Si2C

abstract:
  We report on the valence fluctuation of Ce in CeMo$_{2}$Si$_{2}$C as studied
by means of magnetic susceptibility $\chi(T)$, specific heat $C(T)$, electrical
resistivity $\rho(T)$ and x-ray absorption spectroscopy. Powder x-ray
diffraction revealed that CeMo$_{2}$Si$_{2}$C crystallizes in
CeCr$_{2}$Si$_{2}$C-type layered tetragonal crystal structure (space group
\textit{P4/mmm}). The unit cell volume of CeMo$_{2}$Si$_{2}$C deviates from the
expected lanthanide contraction, indicating non-trivalent state of Ce ions in
this compound. The observed weak temperature dependence of the magnetic
susceptibility and its low value indicate that Ce ions are in valence
fluctuating state. The formal $L_{III}$ Ce valence in CeMo$_{2}$Si$_{2}$C
$<$$\widetilde{\nu}$$>$ = 3.11 as determined from x-ray absorption spectroscopy
measurement is well bellow the value $<$$\widetilde{\nu}$$> \simeq$ 3.4 in
tetravalent Ce compound CeO$_{2}$. The temperature dependence of specific heat
does not show any anomaly down to 1.8 K which rules out any magnetic ordering
in the system. The Sommerfeld coefficient obtained from the specific heat data
is $\gamma$ = 23.4 mJ/mol\,K$^{2}$. The electrical resistivity follows the
$T{^2}$ behavior in the low temperature range below 35 K confirming a Fermi
liquid behavior. Accordingly both the Kadowaki Wood ratio $A/\gamma^{2}$ and
the Sommerfeld Wilson ratio $\chi(0)/\gamma$ are in the range expected for
Fermi-liquid systems. In order to get some information on the electronic
states, we calculated the band structure within the density functional theory,
eventhough this approach is not able to treat 4f electrons accurately. The
non-$f$ electron states crossing the Fermi level have mostly Mo 4d character.
They provide the states with which the 4f sates are strongly hybridized,
leading to the intermediate valent state.


title: MUSE: Multi-algorithm collaborative crystal structure prediction

abstract:
  The algorithm and testing of the Multi-algorithm-collaborative Universal
Structure-prediction Environment ({\sc Muse}) are detailed. Presently, in {\sc
Muse} I combined the evolutionary, the simulated annealing, and the basin
hopping algorithms to realize high-efficiency structure predictions of
materials under certain conditions. {\sc Muse} is kept open and other
algorithms can be added in future. I introduced two new operators, slip and
twist, to increase the diversity of structures. In order to realize the
self-adaptive evolution of structures, I also introduced the competition scheme
among the ten variation operators, as is proved to further increase the
diversity of structures. The symmetry constraints in the first generation, the
multi-algorithm collaboration, the ten variation operators, and the
self-adaptive scheme are all key to enhancing the performance of {\sc Muse}. To
study the search ability of {\sc Muse}, I performed extensive tests on
different systems, including the metallic, covalent, and ionic systems. All
these present tests show {\sc Muse} has very high efficiency and 100% success
rate.


title:
Explaining temporal trends in annualized relapse rates in placebo groups
  of randomized controlled trials in relapsing multiple sclerosis: systematic
  review and meta-regression

abstract:
  Background: Recent studies have shown a decrease in annualised relapse rates
(ARRs) in placebo groups of randomised controlled trials (RCTs) in relapsing
multiple sclerosis (RMS).
  Methods: We conducted a systematic literature search of RCTs in RMS. Data on
eligibility criteria and baseline characteristics were extracted and tested for
significant trends over time. A meta-regression was conducted to estimate their
contribution to the decrease of trial ARRs over time.
  Results: We identified 56 studies. Patient age at baseline (p < 0.001), mean
duration of multiple sclerosis (MS) at baseline (p = 0.048), size of treatment
groups (p = 0.003), Oxford Quality Scale scores (p = 0.021), and the number of
eligibility criteria (p<0.001) increased significantly, whereas pre-trial ARR
(p = 0.001), the time span over which pre-trial ARR was calculated (p < 0.001),
and the duration of placebo-controlled follow-up (p = 0.006) decreased
significantly over time. In meta-regression of trial placebo ARR, the temporal
trend was found to be insignificant, with major factors explaining the
variation: pre-trial ARR, the number of years used to calculate pre-trial ARR
and study duration. Conclusion: The observed decline in trial ARRs may result
from decreasing pre-trial ARRs and a shorter time period over which pre-trial
ARRs were calculated. Increasing patient age and duration of illness may also
contribute.


title:
Robust output synchronization of a network of heterogeneous nonlinear
  agents via nonlinear regulation theory

abstract:
  In this paper, we consider the output synchronization problem for a network
of heterogeneous diffusively-coupled nonlinear agents. Specifically, we show
how the (non-identical) agents can be controlled in such a way that their
outputs asymptotically track the output of a prescribed nonlinear exosystem.
The problem is solved in two steps. In the first step, the problem of achieving
consensus among (identical) nonlinear reference generators is addressed. In
this respect, it is shown how the techniques recently developed to solve the
consensus problem among linear agents can be extended to agents modeled by
nonlinear d-dimensional differential equations, under the assumption that the
communication graph is connected. In the second step, the theory of nonlinear
output regulation is applied in a decentralized control mode, to force the
output of each agent of the network to robustly track the (synchronized) output
of a local reference model.


title: The chemistry of dust formation in red supergiants

abstract:
  Massive stars in their late stages of evolution as Red Supergiants experience
mass loss. The resulting winds show various degrees of dynamical and chemical
complexity and produce molecules and dust grains. This review summarises our
knowledge of the molecular and dust components of the wind of Red Supergiants,
including VY CMa and Betelgeuse. We discuss the synthesis of dust as a
non-equilibrium process in stellar winds, and present the current knowledge of
the chemistry involved in the formation of oxygen-rich dust such as silicates
and metal oxides.


title: Spin-orbit coupling in hydrogenated graphene

abstract:
  First-principles calculations of the spin-orbit coupling in graphene with
hydrogen adatoms in dense and dilute limits are presented. The chemisorbed
hydrogen induces a giant local enhancement of spin-orbit coupling due to $sp^3$
hybridization which depends strongly on the local lattice distortion. Guided by
the reduced symmetry and the local structure of the induced dipole moments we
use group theory to propose realistic minimal Hamiltonians that reproduce the
relevant spin-orbit effects for both single-side semihydrogenated graphene
(graphone) and for a single hydrogen adatom in a large supercell. The principal
linear spin-orbit band splittings are driven by the breaking of the local
pseudospin inversion symmetry and the emergence of spin flips on the same
sublattice.


title: Cohomological rigidity of oriented Hantzsche-Wendt manidolds

abstract:
  By Hantzsche-Wendt manifold (for short HW-manifold) we understand any
oriented closed Riemannian manifold of dimension n with a holonomy group
(Z_2)^{n-1}. Two HW-manifolds M_1 and M_2 are cohomological rigid if and only
if a homeomorphism between M_1 and M_2 is equivalent to an isomorphism of
graded rings H^{*}(M_1,F_2) and H^{*}(M_2,F_2). We prove that HW-manifolds are
cohomological rigid.


title:
A nonlinear prerelativistic approach to mathematical representation of
  vacuum electromagnetism

abstract:
  This paper presents an alternative prerelativistic approach to the vacuum
case of classical electrodynamics represented by vacuum Maxwell equations. Our
view is based on the understanding that the corresponding differential
equations should be dynamical in nature and the physical relations represented
by them should be directly verifiable at least in principle, so they must
represent local energy-momentum balance relations.


title: Landau Level Mixing in the Perturbative Limit

abstract:
  We study the effects of Landau level mixing in the limit of weak electron
interaction. We use a numerical method to obtain the two- and three-body
corrections to quantum Hall pseudopotentials, which are exact to lowest order
in the Landau level mixing parameter. Our results are in general agreement with
certain analytic results (some derived here, some derived by other authors) in
the thermodynamic limit. We find that the convergence to this thermodynamic
limit can be slow. This suggests that errors could occur if one tries to use
pseudopotentials derived in a thermodynamic limit for numerical work on finite
systems.


title:
Adaptive Thouless-Anderson-Palmer approach to inverse Ising problems
  with quenched random fields

abstract:
  The adaptive Thouless-Anderson-Palmer equation is derived for inverse Ising
problems in the presence of quenched random fields. We test the proposed scheme
on Sherrington-Kirkpatrick, Hopfield, and random orthogonal models and find
that the adaptive Thouless-Anderson-Palmer approach allows surprisingly
accurate inference of quenched random fields whose distribution can be either
Gaussian or bimodal, compared with other existing mean-field methods.


title:
Photonic Simulation of System-Environment Interaction: Non-Markovian
  Process and Dynamical Decoupling

abstract:
  The system-environment interaction is simulated by light propagating in
coupled photonic waveguides. The profile of the electromagnetic field provides
intuitive physical insight to study the Markovian and non-Markovian dynamics of
open quantum systems. The transition from non-Markovian to Markovian process is
demonstrated by increasing the size of environment, as the energy evolution
changes from oscillating to an exponential decay, and the revival period
increases. Moreover, the dynamical decoupling with a sequence of phase
modulations is introduced to such a photonic open system to form a band
structure in time dimension, where the energy dissipation can be significantly
accelerated or inhibited. It opens the possibility to tune the dissipation in
photonic system, similar to the dynamic decoupling of spins.


title:
Energy-Efficient Power Control for Contention-Based Synchronization in
  OFDMA Systems with Discrete Powers and Limited Feedback

abstract:
  This work derives a distributed and iterative algorithm by which mobile
terminals can selfishly control their transmit powers during the
synchronization procedure specified by the IEEE 802.16m and the 3GPP-LTE
standards for orthogonal frequency-division multiple-access technologies. The
proposed solution aims at maximizing the energy efficiency of the network and
is derived on the basis of a finite noncooperative game in which the players
have discrete action sets of transmit powers. The set of Nash equilibria of the
game is investigated, and a distributed power control algorithm is proposed to
achieve synchronization in an energy-efficient manner under the assumption that
the feedback from the base station is limited. Numerical results show that the
proposed solution improves the energy efficiency as well as the timing
estimation accuracy of the network compared to existing alternatives, while
requiring a reasonable amount of information to be exchanged on the return
channel.


title:
Nucleosynthesis constraint on Lorentz invariance violation in the
  neutrino sector

abstract:
  We investigate the nucleosynthesis constraint on Lorentz invariance violation
in the neutrino sector which influences the formation of light elements by
altering the energy density of the Universe and weak reaction rates prior to
and during the big-bang nucleosynthesis epoch. We derive the weak reaction
rates in the Lorentz-violating extension of the standard model. Using
measurements of the primordial helium-4 and deuterium abundances, we give a
tighter constraint on the deformed parameter than that derived from
measurements of the cosmic microwave background anisotropies.


title: Convergence rate of Markov chain methods for genomic motif discovery

abstract:
  We analyze the convergence rate of a simplified version of a popular Gibbs
sampling method used for statistical discovery of gene regulatory binding
motifs in DNA sequences. This sampler satisfies a very strong form of
ergodicity (uniform). However, we show that, due to multimodality of the
posterior distribution, the rate of convergence often decreases exponentially
as a function of the length of the DNA sequence. Specifically, we show that
this occurs whenever there is more than one true repeating pattern in the data.
In practice there are typically multiple such patterns in biological data, the
goal being to detect the most well-conserved and frequently-occurring of these.
Our findings match empirical results, in which the motif-discovery Gibbs
sampler has exhibited such poor convergence that it is used only for finding
modes of the posterior distribution (candidate motifs) rather than for
obtaining samples from that distribution. Ours are some of the first meaningful
bounds on the convergence rate of a Markov chain method for sampling from a
multimodal posterior distribution, as a function of statistical quantities like
the number of observations.


title:
The vector coupling $\alpha_{\rm V}(r)$ and the scales $r_0,r_1$ from
  the bottomonium spectrum

abstract:
  We study the universal static potential $V_{\rm st}(r)$ and the force, which
are fully determined by two fundamental parameters: the string tension
$\sigma=0.18\pm 0.02$ GeV$^2$ and the QCD constants $\Lambda_{\bar{\rm
MS}}(n_f)$, taken from pQCD, while the infrared (IR) regulator $M_{\rm B}$ is
taken from the background perturbation theory and expressed via the string
tension. The vector couplings $\alpha_{\rm V}(r)$ in the static potential and
$\alpha_{\rm F}(r)$ in the static force, as well as the characteristic scales,
$r_1(n_f=3)$ and $r_0(n_f=3)$, are calculated and compared to lattice data. The
result $r_0\Lambda_{\bar{\rm MS}}(n_f=3)=0.77\pm 0.03$, which agrees with the
lattice data, is obtained for $M_{\rm B}=(1.15\pm 0.02)$ GeV. However, better
agreement with the bottomonium spectrum is reached for a smaller
$\Lambda_{\bar{\rm MS}}(n_f=3)=(325\pm 15)$ MeV and the frozen value of
$\alpha_V=0.57\pm 0.02$. The mass splittings $\bar M(1D)-\bar M(1P)$ and $\bar
M(2P)-\bar M(1P)$ are shown to be sensitive to the IR regulator used. The
masses $M(1\,^3D_3)=10169(2)$ MeV and $M(1\,^3D_1)=10155(3)$ MeV are predicted.


title: Internal Gerstner waves: applications to dead water

abstract:
  We give an explicit solution describing internal waves with a still water
surface, modelling the dead water phenomenon, on the basis of the Gerstner wave
solution to the Euler equations.


title: A Tutorial on the Optimization of Amplify-and-Forward MIMO Relay Systems

abstract:
  The remarkable promise of multiple-input multiple-output (MIMO) wireless
channels has motivated an intense research activity to characterize the
theoretical and practical issues associated with the design of transmit
(source) and receive (destination) processing matrices under different
operating conditions. This activity was primarily focused on point-to-point
(single-hop) communications but more recently there has been an extensive work
on two-hop or multi-hop settings in which single or multiple relays are used to
deliver the information from the source to the destination. The aim of this
tutorial is to provide an up-to-date overview of the fundamental results and
practical implementation issues of designing amplify-and-forward MIMO relay
systems.


title: Dynamical Screening Effect on Local Two-Particle Vertex Functions

abstract:
  In principle, the electronic Coulomb interaction among the correlated
orbitals is frequency-dependent. Though it is generally believed that the
dynamically screened interaction may play a crucial role in understanding the
subtle electronic structures of strongly correlated materials, hitherto we know
very little about it. In the Letter, we demonstrate that within the framework
of single-site dynamical mean-field theory the local two-particle Green's
functions $\chi$ and vertex functions $\Gamma$ are strongly modified by the
dynamically screened interaction. Since both $\chi$ and $\Gamma$ represent the
main ingredients to compute momentum-resolved response functions and to treat
non-local spatial correlations by means of diagrammatic extensions of dynamical
mean-field theory, it is urgent to reexamine previous results by taking the
dynamical screening effect into account. The modifications should be very
considerable.


title: Analysis of the binary asymmetric joint sparse form

abstract:
  We consider redundant binary joint digital expansions of integer vectors. The
redundancy is used to minimize the Hamming weight, i.e., the number of nonzero
digit vectors. This leads to efficient linear combination algorithms in abelian
groups, which are for instance used in elliptic curve cryptography.
  If the digit set is a set of contiguous integers containing the zero, a
special syntactical condition is known to minimize the weight. We analyze the
optimal weight of all non-negative integer vectors with maximum entry less than
N. The expectation and the variance are given with a main term and a periodic
fluctuation in the second order term. Finally, we prove asymptotic normality.


title:
Power Allocation in Two-Hop Amplify-and-Forward MIMO Relay Systems with
  QoS requirements

abstract:
  The problem of minimizing the total power consumption while satisfying
different quality-of-service (QoS) requirements in a two-hop multiple-input
multiple-output network with a single non-regenerative relay is considered. As
shown by Y. Rong in [1], the optimal processing matrices for both linear and
non-linear transceiver architectures lead to the diagonalization of the
source-relay-destination channel so that the power minimization problem reduces
to properly allocating the available power over the established links.
Unfortunately, finding the solution of this problem is numerically difficult as
it is not in a convex form. To overcome this difficulty, existing solutions
rely on the computation of upper- and lower-bounds that are hard to obtain or
require the relaxation of the QoS constraints. In this work, a novel approach
is devised for both linear and non-linear transceiver architectures, which
allows to closely approximate the solutions of the non-convex power allocation
problems with those of convex ones easy to compute in closed-form by means of
multi-step procedures of reduced complexity. Computer simulations are used to
assess the performance of the proposed approach and to make comparisons with
alternatives.


title:
Kinetic Control of Recombination in Organic Photovoltaics: The Role of
  Spin

abstract:
  In photovoltaic diodes recombination of photogenerated electrons and holes is
a major loss process. Biological light harvesting complexes (LHCs) prevent
recombination via the use of cascade structures, which lead to spatial
separation of charge-carriers1. In contrast, the nanoscale morphology and high
charge densities in organic photovoltaic cells (OPVs) give a high rate of
electron-hole encounters, which should result in the formation of spin triplet
excitons, as in organic light emitting diodes (OLEDs)2. OPVs would have poor
quantum efficiencies if every encounter lead to recombination, but
state-of-the-art OPVs demonstrate near-unity quantum efficiency3. Here we show
that this suppression of recombination can be engineered through the interplay
between spin, energetics and delocalisation of electronic excitations in
organic semiconductors. We use time-resolved spectroscopy to study a series of
model, high efficiency polymer-fullerene systems in which the lowest lying
molecular triplet exciton (T1) (on the polymer) lies below the intermolecular
charge transfer state (CT). We observe the formation of T1 states following
bimolecular recombination, indicating that encounters of spin-uncorrelated
electrons and holes generate CT states with both spin singlet (1CT) and spin
triplet (3CT) characters. We show that triplet exciton formation can be the
major loss mechanism in OPVs. However, we find that even when energetically
favoured, the relaxation of 3CT to T1 can be strongly suppressed, via control
over wavefunction delocalisation, allowing for the dissociation of 3CT back to
free changes, thereby reducing recombination and enhancing device performance.
Our results point towards new design rules for artificial photo-conversion
systems, enabling the suppression of electron-hole recombination, and also for
OLEDs, avoiding the formation of triplet states and enhancing fluorescence
efficiency.


title: Renormalization group analysis of multi-Dirac-node materials

abstract:
  We theoretically study the electromagnetic interaction in Dirac systems with
$N$ nodes by using the renormalization group, which is relevant to the quantum
critical phenomena of topological phase transition ($N=1$) and Weyl semimetals
($N=4$ or $N=12$). Compared with the previous work for $N=1$ [H. Isobe and N.
Nagaosa, Phys. Rev. B 86, 165127 (2012); arXiv:1205.2427], we obtained the
analytic solution for the large $N$ limit, which differs qualitatively for the
scaling of the speed of light $c$ and that of electron $v$, i.e., $v$ does
notchange while $c$ is reduced to $v$. We also found a reasonably accurate
approximate analytic solution for generic $N$, which well interpolates between
$N=1$ and large $N$ limit, and it concludes that $c^2 v^N$ is almost
unrenormalized. The temperature dependence of the physical properties, the
dielectric constant, magnetic susceptibility, spectral function, DC
conductivity, and mass gap are discussed based on these results.


title: Gaussian Processes for Nonlinear Signal Processing

abstract:
  Gaussian processes (GPs) are versatile tools that have been successfully
employed to solve nonlinear estimation problems in machine learning, but that
are rarely used in signal processing. In this tutorial, we present GPs for
regression as a natural nonlinear extension to optimal Wiener filtering. After
establishing their basic formulation, we discuss several important aspects and
extensions, including recursive and adaptive algorithms for dealing with
non-stationarity, low-complexity solutions, non-Gaussian noise models and
classification scenarios. Furthermore, we provide a selection of relevant
applications to wireless digital communications.


title: Fourth-order flows in surface modelling

abstract:
  This short article is a brief account of the usage of fourth-order curvature
flow in surface modelling.


title: Orthogonal polynomials, a short introduction

abstract:
  This paper is a short introduction to orthogonal polynomials, both the
general theory and some special classes. It ends with some remarks about the
usage of computer algebra for this theory.


title: Probabilistic Topic and Syntax Modeling with Part-of-Speech LDA

abstract:
  This article presents a probabilistic generative model for text based on
semantic topics and syntactic classes called Part-of-Speech LDA (POSLDA).
POSLDA simultaneously uncovers short-range syntactic patterns (syntax) and
long-range semantic patterns (topics) that exist in document collections. This
results in word distributions that are specific to both topics (sports,
education, ...) and parts-of-speech (nouns, verbs, ...). For example,
multinomial distributions over words are uncovered that can be understood as
"nouns about weather" or "verbs about law". We describe the model and an
approximate inference algorithm and then demonstrate the quality of the learned
topics both qualitatively and quantitatively. Then, we discuss an NLP
application where the output of POSLDA can lead to strong improvements in
quality: unsupervised part-of-speech tagging. We describe algorithms for this
task that make use of POSLDA-learned distributions that result in improved
performance beyond the state of the art.


title:
Linear system identification using stable spline kernels and PLQ
  penalties

abstract:
  The classical approach to linear system identification is given by parametric
Prediction Error Methods (PEM). In this context, model complexity is often
unknown so that a model order selection step is needed to suitably trade-off
bias and variance. Recently, a different approach to linear system
identification has been introduced, where model order determination is avoided
by using a regularized least squares framework. In particular, the penalty term
on the impulse response is defined by so called stable spline kernels. They
embed information on regularity and BIBO stability, and depend on a small
number of parameters which can be estimated from data. In this paper, we
provide new nonsmooth formulations of the stable spline estimator. In
particular, we consider linear system identification problems in a very broad
context, where regularization functionals and data misfits can come from a rich
set of piecewise linear quadratic functions. Moreover, our anal- ysis includes
polyhedral inequality constraints on the unknown impulse response. For any
formulation in this class, we show that interior point methods can be used to
solve the system identification problem, with complexity O(n3)+O(mn2) in each
iteration, where n and m are the number of impulse response coefficients and
measurements, respectively. The usefulness of the framework is illustrated via
a numerical experiment where output measurements are contaminated by outliers.


title:
Maximal Chains of Isomorphic Suborders of Countable Ultrahomogeneous
  Partial Orders

abstract:
  We investigate the poset (P(X),\subset), where P(X) is the set of isomorphic
suborders of a countable ultrahomogeneous partial order X. For X different from
(resp. equal to) a countable antichain the order types of maximal chains in
(P(X)\cup \{\emptyset \},\subset) are characterized as the order types of
compact (resp. compact and nowhere dense) sets of reals having the minimum
non-isolated.


abstract:
  The Accurate fission data for nuclear safety (AlFONS) project aims at high
precision measurements of fission yields, using the renewed IGISOL mass
separator facility in combination with a new high current light ion cyclotron
at the University of Jyvaskyla. The 30 MeV proton beam will be used to create
fast and thermal neutron spectra for the study of neutron induced fission
yields. Thanks to a series of mass separating elements, culminating with the
JYFLTRAP Penning trap, it is possible to achieve a mass resolving power in the
order of a few hundred thousands.
  In this paper we present the experimental setup and the design of a neutron
converter target for IGISOL. The goal is to have a flexible design. For studies
of exotic nuclei far from stability a high neutron flux (10^12 neutrons/s) at
energies 1 - 30 MeV is desired while for reactor applications neutron spectra
that resembles those of thermal and fast nuclear reactors are preferred. It is
also desirable to be able to produce (semi-)monoenergetic neutrons for
benchmarking and to study the energy dependence of fission yields.
  The scientific program is extensive and is planed to start in 2013 with a
measurement of isomeric yield ratios of proton induced fission in uranium. This
will be followed by studies of independent yields of thermal and fast neutron
induced fission of various actinides.


title:
Almost sure convergence of a randomized algorithm for relative
  localization in sensor networks

abstract:
  This paper regards the relative localization problem in sensor networks. We
study a randomized algorithm, which is based on input-driven consensus dynamics
and involves pairwise "gossip" communications and updates. Due to the
randomness of the updates, the state of this algorithm ergodically oscillates
around a limit value. Exploiting the ergodicity of the dynamics, we show that
the time-average of the state almost surely converges to the least-squares
solution of the localization problem. Remarkably, the computation of the
time-average does not require the sensors to share any common clock. Hence, the
proposed algorithm is fully distributed and asynchronous.


title:
Microwave spectroscopic study of the hyperfine structure of antiprotonic
  helium-3

abstract:
  In this work we describe the latest results for the measurements of the
hyperfine structure of antiprotonic helium-3. Two out of four measurable
super-super-hyperfine SSHF transition lines of the (n,L)=(36,34) state of
antiprotonic helium-3 were observed. The measured frequencies of the individual
transitions are 11.12548(08) GHz and 11.15793(13) GHz, with an increased
precision of about 43% and 25% respectively compared to our first measurements
with antiprotonic helium-3 [S. Friedreich et al., Phys. Lett. B 700 (2011)
1--6]. They are less than 0.5 MHz higher with respect to the most recent
theoretical values, still within their estimated errors. Although the
experimental uncertainty for the difference of 0.03245(15) GHz between these
frequencies is large as compared to that of theory, its measured value also
agrees with theoretical calculations. The rates for collisions between
antiprotonic helium and helium atoms have been assessed through comparison with
simulations, resulting in an elastic collision rate of gamma_e = 3.41 +- 0.62
MHz and an inelastic collision rate of gamma_i = 0.51 +- 0.07 MHz.


title: Local random quantum circuits: ensemble CP maps and swap algebras

abstract:
  We define different classes of local random quantum circuits (L-RQC) and show
that: a) statistical properties of L-RQC are encoded into an associated family
of completely positive maps and b) average purity dynamics can be described by
the action of these maps on operator algebras of permutations (swap algebras).
An exactly solvable one-dimensional case is analyzed to illustrate the power of
the swap algebra formalism. More in general, we prove short time area-law
bounds on average purity for uncorrelated L-RQC and infinite time results for
both the uncorrelated and correlated cases.


title: Limit of light coupling strength in solar cells

abstract:
  We introduce a limit for the strength of coupling light into the modes of
solar cells. This limit depends on both a cell's thickness and its modal
properties. For a cell with refractive index n and thickness d, we obtain a
maximal coupling rate of 2c*sqrt(n^2-1)/d where c is speed of light. Our method
can be used in the design of solar cells and in calculating their efficiency
limits; besides, it can be applied to a broad variety of resonant phenomena and
devices.


title: Psi-Epistemic Theories: The Role of Symmetry

abstract:
  Formalizing an old desire of Einstein, "psi-epistemic theories" try to
reproduce the predictions of quantum mechanics, while viewing quantum states as
ordinary probability distributions over underlying objects called "ontic
states." Regardless of one's philosophical views about such theories, the
question arises of whether one can cleanly rule them out, by proving no-go
theorems analogous to the Bell Inequality. In the 1960s, Kochen and Specker
(who first studied these theories) constructed an elegant psi-epistemic theory
for Hilbert space dimension d=2, but also showed that any deterministic
psi-epistemic theory must be "measurement contextual" in dimensions 3 and
higher. Last year, the topic attracted renewed attention, when Pusey, Barrett,
and Rudolph (PBR) showed that any psi-epistemic theory must "behave badly under
tensor product." In this paper, we prove that even without the Kochen-Specker
or PBR assumptions, there are no psi-epistemic theories in dimensions d>=3 that
satisfy two reasonable conditions: (1) symmetry under unitary transformations,
and (2) "maximum nontriviality" (meaning that the probability distributions
corresponding to any two non-orthogonal states overlap). This no-go theorem
holds if the ontic space is either the set of quantum states or the set of
unitaries. The proof of this result, in the general case, uses some measure
theory and differential geometry. On the other hand, we also show the
surprising result that without the symmetry restriction, one can construct
maximally-nontrivial psi-epistemic theories in every finite dimension d.


title:
Angular behavior of the absorption limit in thin film silicon solar
  cells

abstract:
  We investigate the angular behavior of the upper bound of absorption provided
by the guided modes in thin film solar cells. We show that the 4n^2 limit can
be potentially exceeded in a wide angular and wavelength range using
two-dimensional periodic thin film structures. Two models are used to estimate
the absorption enhancement; in the first one, we apply the periodicity
condition along the thickness of the thin film structure but in the second one,
we consider imperfect confinement of the wave to the device. To extract the
guided modes, we use an automatized procedure which is established in this
work. Through examples, we show that from the optical point of view, thin film
structures have a high potential to be improved by changing their shape. Also,
we discuss the nature of different optical resonances which can be potentially
used to enhance light trapping in the solar cell. We investigate the two
different polarization directions for one-dimensional gratings and we show that
the transverse magnetic polarization can provide higher values of absorption
enhancement. We also propose a way to reduce the angular dependence of the
solar cell efficiency by the appropriate choice of periodic pattern. Finally,
to get more practical values for the absorption enhancement, we consider the
effect of parasitic loss which can significantly reduce the enhancement factor.


title:
PReMiuM: An R Package for Profile Regression Mixture Models using
  Dirichlet Processes

abstract:
  PReMiuM is a recently developed R package for Bayesian clustering using a
Dirichlet process mixture model. This model is an alternative to regression
models, non-parametrically linking a response vector to covariate data through
cluster membership. The package allows Bernoulli, Binomial, Poisson, Normal and
categorical response, as well as Normal and discrete covariates. Additionally,
predictions may be made for the response, and missing values for the covariates
are handled. Several samplers and label switching moves are implemented along
with diagnostic tools to assess convergence. A number of R functions for
post-processing of the output are also provided. In addition to fitting
mixtures, it may additionally be of interest to determine which covariates
actively drive the mixture components. This is implemented in the package as
variable selection.


title:
Asynchronous Distributed Optimization using a Randomized Alternating
  Direction Method of Multipliers

abstract:
  Consider a set of networked agents endowed with private cost functions and
seeking to find a consensus on the minimizer of the aggregate cost. A new class
of random asynchronous distributed optimization methods is introduced. The
methods generalize the standard Alternating Direction Method of Multipliers
(ADMM) to an asynchronous setting where isolated components of the network are
activated in an uncoordinated fashion. The algorithms rely on the introduction
of randomized Gauss-Seidel iterations of a Douglas-Rachford operator for
finding zeros of a sum of two monotone operators. Convergence to the sought
minimizers is provided under mild connectivity conditions. Numerical results
sustain our claims.


title:
A review of depth-averaged models for dry granular flows: Savage-Hutter
  and $\mu(I)$-rheology

abstract:
  In this work we present a review of the most popular depth-averaged models to
simulate dry granular flows such as aerial avalanches. The classical
Savage-Hutter model and recent ones using a $\mu(I)$-rheology law are studied.
The objective is firstly to point out the advantages of each such models and
secondly to understand how the hypothesis considered in the derivation process
influence on the final system.


title: A Note Basis Properties for Fractional Hydrogen Atom Equation

abstract:
  In this paper, spectral analysis of fractional Sturm Liouville problem
defined on (0,1], having the singularity of type at zero and research the
fundamental properties of the eigenfunctions and eigenvalues for the operator.
We show that the eigenvalues and eigenfunctions of the problem are real and
orthogonal, respectively. Furthermore,we give some important theorems and
lemmas for fractional hydrogen atom equation.


title: The E-Eigenvectors of Tensors

abstract:
  We first show that the eigenvector of a tensor is well-defined. The
differences between the eigenvectors of a tensor and its E-eigenvectors are the
eigenvectors on the nonsingular projective variety $\mathbb S=\{\mathbf
x\in\mathbb P^n\;|\;\sum\limits_{i=0}^nx_i^2=0\}$. We show that a generic
tensor has no eigenvectors on $\mathbb S$. Actually, we show that a generic
tensor has no eigenvectors on a proper nonsingular projective variety in
$\mathbb P^n$. By these facts, we show that the coefficients of the
E-characteristic polynomial are algebraically dependent. Actually, a certain
power of the determinant of the tensor can be expressed through the
coefficients besides the constant term. Hence, a nonsingular tensor always has
an E-eigenvector. When a tensor $\mathcal T$ is nonsingular and symmetric, its
E-eigenvectors are exactly the singular points of a class of hypersurfaces
defined by $\mathcal T$ and a parameter. We give explicit factorization of the
discriminant of this class of hypersurfaces, which completes Cartwright and
Strumfels' formula. We show that the factorization contains the determinant and
the E-characteristic polynomial of the tensor $\mathcal T$ as irreducible
factors.


title:
Warm gas in the rotating disk of the Red Rectangle: accurate models of
  molecular line emission

abstract:
  We aim to study the excitation conditions of the molecular gas in the
rotating disk of the Red Rectangle, the only post-Asymptotic-Giant-Branch
object in which the existence of an equatorial rotating disk has been
demonstrated. For this purpose, we developed a complex numerical code that
accurately treats radiative transfer in 2-D, adapted to the study of molecular
lines from rotating disks.
  We present far-infrared Herschel/HIFI observations of the 12CO and 13CO
J=6-5, J=10-9, and J=16-15 transitions in the Red Rectangle. We also present
our code in detail and discuss the accuracy of its predictions, from comparison
with well-tested codes. Theoretical line profiles are compared with the
empirical data to deduce the physical conditions in the disk by means of model
fitting.
  We conclude that our code is very efficient and produces reliable results.
The comparison of the theoretical predictions with our observations reveals
that the temperature of the Red Rectangle disk is typically ~ 100-150 K, about
twice as high as previously deduced from mm-wave observations of lower-J lines.
We discuss the relevance of these new temperature estimates for understanding
the thermodynamics and dynamics of this prototype object, as well as for
interpreting observations of other rarely studied post-AGB disks. Despite our
sophisticated treatment of the line formation, our model cannot explain the
relatively strong line-wing emission for intermediate-J transitions. We argue
that a model including a rotating disk only cannot reproduce these data and
suggest that there is an additional extended (probably bipolar) structure
expanding at about 7--15 km/s.


title: Collider Physics within the Standard Model: a Primer

abstract:
  The first LHC results at 7-8 TeV, with the discovery of a candidate Higgs
boson and the non observation of new particles or exotic phenomena, have made a
big step towards completing the experimental confirmation of the Standard Model
(SM) of fundamental particle interactions. It is thus a good moment for me to
collect, update and improve my graduate lecture notes on Quantum Chromodynamics
(QCD) and the theory of Electroweak (EW) Interactions, with main focus on
Collider Physics. I hope that these lectures can provide an introduction to the
subject for the interested reader, assumed to be already familiar with quantum
field theory and some basic facts in elementary particle physics as taught in
undergraduate courses.


title: Curvature perturbations of quasidilaton non-linear massive gravity

abstract:
  We study the cosmological perturbations of the recently proposed extension of
non-linear massive gravity with a scalar field. The added scalar field ensures
a new symmetry on the field space of the theory. The theory has the property of
having a flat dS solution, in contrast to the standard dRGT massive gravity.
The tensor part is the same as that of the standard dRGT and shows
gravitational waves with a time dependent mass which modifies the dispersion
relation. We obtain the curvature perturbation of the model on superhorizon
scales for a specific choice of $\omega=0$ and find that the theory does not
allow a constant curvature perturbation on the superhorizon scales and we have
always a growing mode. The consistency of equations restricts the parameter
space of the theory.


title: A Stochastic Grammar for Natural Shapes

abstract:
  We consider object detection using a generic model for natural shapes. A
common approach for object recognition involves matching object models directly
to images. Another approach involves building intermediate representations via
a generic grouping processes. We argue that these two processes (model-based
recognition and grouping) may use similar computational mechanisms. By defining
a generic model for shapes we can use model-based techniques to implement a
mid-level vision grouping process.


title: Matter-wave solitons in the counterflow of two immiscible superfluids

abstract:
  We study formation of solitons induced by counterflows of immiscible
superfluids. Our setting is based on a quasi-one-dimensional binary
Bose-Einstein condensate (BEC), composed of two immiscible components with
large and small numbers of atoms in them. Assuming that the "small" component
moves with constant velocity, either by itself, or being dragged by a moving
trap, and intrudes into the "large" counterpart, the following results are
obtained. Depending on the velocity, and on whether the small component moves
in the absence or in the presence of the trap, two-component dark-bright
solitons, scalar dark solitons, or multiple dark solitons may emerge, the
latter outcome taking place due to breakdown of the superfluidity. We present
two sets of analytical results to describe this phenomenology. In an
intermediate velocity regime, where dark-bright solitons form, a reduction of
the two-component Gross-Pitaevskii system to an integrable Mel'nikov system is
developed, demonstrating that solitary waves of the former are very accurately
described by analytically available solitons of the latter. In the
high-velocity regime, where the breakdown of the superfluidity induces the
formation of dark solitons and multi-soliton trains, an effective
single-component description, in which a strongly localized wave packet of the
"small" component acts as an effective potential for the "large" one, allows us
to estimate the critical velocity beyond which the coherent structures emerge
in good agreement with the numerical results.


title:
Halpha3: an Halpha imaging survey of HI selected galaxies from ALFALFA.
  II. The star formation properties of galaxies in the Virgo cluster and
  surroundings

abstract:
  We present the analysis of Halpha3, an Halpha imaging survey of 409 galaxies
selected from the HI Arecibo ALFALFA Survey in the Local Supercluster,
including the Virgo cluster. We explore the relations between the stellar mass,
the HI mass and the current, massive SFR of nearby galaxies in the Virgo
cluster and we compare them with those of isolated galaxies in the Local
Supercluster, disentangling the role of the environment in shaping the star
formation properties of galaxies at the present cosmological epoch. We
investigate the relationships between atomic neutral gas and newly formed stars
in different environments, across many morphological types, and over a wide
range of stellar masses adopting an updated calibration of the HI deficiency
parameter. Studying the mean properties of late-type galaxies in the Local
Supercluster, we find that galaxies in increasing local galaxy density
conditions (or decreasing projected angular separation from M87) show a
significant decrease in the HI content and in the mean specific star formation
rate, along with a progressive reddening of their stellar populations. The
gradual quenching of the star formation occurs outside-in, consistently with
the predictions of the ram pressure model. Once considered as a whole, the
Virgo cluster is effective in removing neutral hydrogen from galaxies, and this
perturbation is strong enough to appreciably reduce the SFR of its entire
galaxy population. An estimate of the present infall rate of 300-400 galaxies
per Gyr in the Virgo cluster is obtained from the number of existing HI-rich
late-type systems, assuming 200-300 Myr as the time scale for HI ablation. If
the infall process has been acting at constant rate this would imply that the
Virgo cluster has formed approximately 2 Gyr ago, consistently with the idea
that Virgo is in a young state of dynamical evolution.


title:
Using head-tail galaxies to constrain the intracluster magnetic field:
  an in-depth study of PKS J0334-3900

abstract:
  We present a multi-wavelength study of the radio galaxy PKS J0334-3900 at the
centre of Abell 3135. The spectro-polarimetric radio observations are combined
with spectroscopic optical and X-ray data to illustrate the use of Head-Tail
radio galaxies to reveal properties of the intracluster medium. ATCA
observations at 1.4, 2.5, 4.6 & 8.6 GHz are presented with a detailed analysis
of the morphology and spectral indices giving physical parameters to constrain
the dynamical history of the galaxy. Using these constraints we produce a
simulation of PKS J0334-3900. We find that this Head-Tail morphology can be
induced via a combination of orbital motion due to a binary companion and
relative motion through the ICM. New Chandra images of A3135 are presented from
which we obtain a cluster electron density of n_(e,0) = (1.06 +/- 0.11 x
10^(-3) cm^(-3), a global temperature of 2.4 ^(+0.51)_(-0.38) keV and a lower
limit to the radio jet power of PKS J0334-3900 of 1.6 x 10^(44) erg/s. A new
redshift analysis of the cluster from available spectroscopic data shows A3135
to be comprised of galaxies with 0.058 < z < 0.066 and gives a new mean cluster
redshift of 0.06228 +/- 0.00015. We also uncovered a background subgroup
between 0.066 < z < 0.070. Stokes Q and U data of Abell 3135 were used to
obtain rotation measure values along the line of sight to PKS J0334-3900. Using
our simulation we are able to infer the distance between the jets to be 154 +/-
16 kpc, which when combined with the difference in rotation measure between the
jets provides a novel new way to estimate the average magnetic field within a
cluster. A lower limit to the cluster B-field was calculated to be 0.09 +/-
0.03 micro Gauss. We show observations of Head-Tail galaxies can be used to
infer information on the cluster environment, showing them to be an important
class of objects in next generation all sky surveys.


title:
A first principles study of the stability and mobility of defects in
  titanium carbide

abstract:
  We have performed density functional calculations of the formation energies
of substitutional transition metal (TM) defects, C vacancies, and C
interstitial defects in TiC. In addition we have evaluated the migration energy
barriers for C atoms in the presence of TM impurities. We find that the
solubility of TM impurities taken from the 3d TM series is low and only Sc and
V impurities can be dissolved into TiC at equilibrium. In addition, we find
that the migration energy barriers of C in TiC are greatly affected by the
presence of TM impurities: The migration barriers are generally lower in the
presence of impurities compared to pure TiC and show a clear dependence on the
atomic size of the TM impurities. We propose that the mobility of C in TiC will
be the highest in the presence of TM impurities from the middle of the 3d TM
series.


title: Bell nonlocality

abstract:
  Bell's 1964 theorem, which states that the predictions of quantum theory
cannot be accounted for by any local theory, represents one of the most
profound developments in the foundations of physics. In the last two decades,
Bell's theorem has been a central theme of research from a variety of
perspectives, mainly motivated by quantum information science, where the
nonlocality of quantum theory underpins many of the advantages afforded by a
quantum processing of information. The focus of this review is to a large
extent oriented by these later developments. We review the main concepts and
tools which have been developed to describe and study the nonlocality of
quantum theory, and which have raised this topic to the status of a full
sub-field of quantum information science.


title: Status and recent results from H.E.S.S

abstract:
  The H.E.S.S. instrument consists of four 13 m (H.E.S.S. I) and one 28 m
diameter (H.E.S.S. II) Atmospheric Cherenkov Telescopes (ACTs) located in the
Khomas Highland in Namibia, 1800 m above sea level. The H.E.S.S. I array began
operations in 2003, and has achieved recent scientific results allowed by the
synergy with the Fermi-LAT, some of which are outlined here. The H.E.S.S. II
telescope started operations in July 2012, and is expected to provide its first
scientific results by the end of the year. Since the inauguration of the first
telescope in September 2002, H.E.S.S. has taken 9415 hours of data, with 4234
hours in the band of the Galaxy and 5181 hours in extragalactic space,
discovered over 80 new very high energy (VHE; E > 100 GeV) {\gamma}-ray sources
(according to TeVCat listings), among them more than 60 galactic objects and 19
extragalactic sources.


title: Fluctuation relations without uniform large deviations

abstract:
  We study the fluctuations of a stochastic Maxwell-Lorentz particle model
driven by an external field to determine the extent to which fluctuation
relations are related to large deviations. Focusing on the total entropy
production of this model in its steady state, we show that, although the
probability density of this quantity globally satisfies (by definition) a
fluctuation relation, its negative tail decays exponentially with time, whereas
its positive tail decays slower than exponentially with time because of long
collision-free trajectories. This provides an example of physical system for
which the fluctuation relation does not derive, as commonly thought, from a
probability density decaying everywhere exponentially with time or, in other
words, from a probability density having a uniform large deviation form.


title:
Universal and optimal error thresholds for measurement-based
  entanglement purification

abstract:
  We investigate measurement-based entanglement purification protocols (EPP) in
the presence of local noise and imperfections. We derive a universal,
protocol-independent threshold for the required quality of the local resource
states, where we show that local noise per particle of up to 24% is tolerable.
This corresponds to an increase of the noise threshold by almost an order of
magnitude, based on the joint measurement-based implementation of sequential
rounds of few-particle EPP. We generalize our results to multipartite EPP,
where we encounter similarly high error thresholds.


title:
Global maximum principles and divergence theorems on complete manifolds
  with boundary

abstract:
  In this paper we extend to non-compact Riemannian manifolds with boundary the
use of two important tools in the geometric analysis of compact spaces, namely,
the weak maximum principle for subharmonic functions and the integration by
parts. The first one is a new form of the classical Ahlfors maximum principle
whereas the second one is a version for manifolds with boundary of the so
called Kelvin-Nevanlinna-Royden criterion of parabolicity. In fact, we will
show that the validity of non-compact versions of these tools serve as a
characterization of the Neumann parabolicity of the space.
  The motivation underlying this study is to obtain new information on the
geometry of graphs with prescribed mean curvature inside a Riemannian product
of the type $N\times\mathbb{R}$. In this direction two kind of results will be
presented: height estimates for constant mean curvature graphs parametrized
over unbounded domains in a complete manifold and slice type results for graphs
whose superlevel sets have finite volume.


title: Large deviation principle for bridges of degenerate diffusions

abstract:
  We prove that bridges of subelliptic diffusions on a compact manifold, with
distinct ends, satisfy a large deviation principle in a space of Holder
continuous functions, with a good rate function, when the travel time tends to
0. This leads to the identification of the deterministic first order
asymptotics of the distribution of the bridge under generic conditions on the
endpoints of the bridge.


title: Reentrant Superconductivity in Eu(Fe1-xIrx)2As2

abstract:
  The interplay between superconductivity and Eu$^{2+}$ magnetic ordering in
Eu(Fe$_{1-x}$Ir$_{x}$)$_{2}$As$_{2}$ is studied by means of electrical
transport and magnetic measurements. For the critically doped sample
Eu(Fe$_{0.86}$Ir$_{0.14}$)$_{2}$As$_{2}$, we witnessed two distinct transitions
: a superconducting transition below 22.6 K which is followed by a resistivity
reentrance caused by the ordering of the Eu$^{2+}$ moments. Further, the low
field magnetization measurements show a prominent diamagnetic signal due to
superconductivity which is remarkable in presence of a large moment
magnetically ordered system. The electronic structure for a 12.5% Ir doped
EuFe$_{1.75}$Ir$_{0.25}$As$_{2}$ is investigated along with the parent compound
EuFe$_{2}$As$_{2}$. As compared to EuFe$_{2}$As$_{2}$, the doped compound has
effectively lower value of density of states throughout the energy scale with
more extended bandwidth and stronger hybridization involving Ir. Shifting of
Fermi energy and change in band filling in EuFe$_{1.75}$Ir$_{0.25}$As$_{2}$
with respect to the pure compound indicate electron doping in the system.


title:
Global Simulations of Magnetorotational Instability in The Collapsed
  Core of A Massive Star

abstract:
  We performed the first numerical simulations of magnetorotational instability
from a sub-magnetar-class seed magnetic field in core collapse supernovae. As a
result of axisymmetric ideal MHD simulations, we found that the magnetic field
is greatly amplified to magnetar-class strength. In saturation phase, a
substantial part of the core is dominated by turbulence, and the magnetic field
possesses dominant large scale components, comparable to the size of the
proto-neutron star. A pattern of coherent chanel flows, which generally appears
during exponential growth phase in previous local simulations, is not observed
in our global simulations. While the approximate convergence in the exponential
growth rate is attained by increasing spatial resolution, that of the
saturation magnetic field is not achieved due to still large numerical
diffusion. Although the effect of magnetic field on the dynamics is found to be
mild, a simulation with a high-enough resolution might result in a larger
impact.


title: Integration of SOA and Cloud Computing in RM-ODP

abstract:
  The objective of ODP is according to ITU-T Recommendation X.901 stated as
follows: The objective of ODP standardization is the development of standards
that allow the benefits of distributing information processing services to be
realized in an environment of heterogeneous IT resources and multiple
organizational domains. These standards address constraints on system
specification and the provision of a system infrastructure that accommodate
difficulties inherent in the design and programming of distributed systems.
This objective seems to cover cloud computing systems. Therefore, we in this
paper discuss the concepts of cloud, and discuss the use of RM-ODP for
specifying the solution. We indicate that the current RM-ODP may be too
abstract for the purpose, and indicate how to adapt RM-ODP to fit the purpose


title:
Psi(2S) production in proton-proton collisions at RHIC, Tevatron and LHC
  energies

abstract:
  We briefly review the existing psi(2S) data taken at RHIC, the Tevatron and
the LHC. We systematically compare them with colour-singlet-model predictions
as a function of the center-of-mass energy, of the quarkonium rapidity and of
the quarkonium transverse momentum. The overall agreement is good except for
large transverse momenta. This points at the existence of large NNLO
corrections or points at colour-octet dominance.


title: Time dependent quantum transport through Kondo correlated quantum dots

abstract:
  In this article, we review recent work about time dependent quantum transport
through a quantum dot in Kondo regime. This represents a major step towards
designing next generation transistors that are expected to replace current
MOSFET's in a few years. We first discuss the effects of the density of states
of gold contacts on the instantaneous conductance of an asymmetrically coupled
quantum dot that is abruptly moved into Kondo regime via a gate voltage. Next,
we investigate the effect of strong electron-phonon coupling on the dot on the
instantaneous conductance. Finally, we discuss thermoelectric effects using
linear response Onsager relations for a quantum dot that is either abruptly
moved into Kondo regime or driven sinusoidally via a gate voltage. We explain
encountered peculiarities in transport based on the behaviour of the density of
states of the dot and the evolution of the Kondo resonance.


title: Fairness in Academic Course Timetabling

abstract:
  We consider the problem of creating fair course timetables in the setting of
a university. Our motivation is to improve the overall satisfaction of
individuals concerned (students, teachers, etc.) by providing a fair timetable
to them. The central idea is that undesirable arrangements in the course
timetable, i.e., violations of soft constraints, should be distributed in a
fair way among the individuals. We propose two formulations for the fair course
timetabling problem that are based on max-min fairness and Jain's fairness
index, respectively. Furthermore, we present and experimentally evaluate an
optimization algorithm based on simulated annealing for solving max-min fair
course timetabling problems. The new contribution is concerned with measuring
the energy difference between two timetables, i.e., how much worse a timetable
is compared to another timetable with respect to max-min fairness. We introduce
three different energy difference measures and evaluate their impact on the
overall algorithm performance. The second proposed problem formulation focuses
on the tradeoff between fairness and the total amount of soft constraint
violations. Our experimental evaluation shows that the known best solutions to
the ITC2007 curriculum-based course timetabling instances are quite fair with
respect to Jain's fairness index. However, the experiments also show that the
fairness can be improved further for only a rather small increase in the total
amount of soft constraint violations.


title:
Fractional discrete processes: compound and mixed Poisson
  representations

abstract:
  We consider two fractional versions of a family of nonnegative integer valued
processes. We prove that their probability mass functions solve fractional
Kolmogorov forward equations, and we show the overdispersion of these
processes. As particular examples in this family, we can define fractional
versions of some processes in the literature as the Polya-Aeppli, the Poisson
Inverse Gaussian and the Negative Binomial. We also define and study some more
general fractional versions with two fractional parameters.


title:
An example of $\alpha$-harmonic map sequence for which energy identity
  is not true

abstract:
  We construct a closed Riemannian manifold $(N,h)$ and a sequence of
$\alpha$-harmonic maps from $S^2$ into $N$ with uniformly bounded energy such
that the energy identity for this sequence is not true.


title: Optimal design for linear models with correlated observations

abstract:
  In the common linear regression model the problem of determining optimal
designs for least squares estimation is considered in the case where the
observations are correlated. A necessary condition for the optimality of a
given design is provided, which extends the classical equivalence theory for
optimal designs in models with uncorrelated errors to the case of dependent
data. If the regression functions are eigenfunctions of an integral operator
defined by the covariance kernel, it is shown that the corresponding measure
defines a universally optimal design. For several models universally optimal
designs can be identified explicitly. In particular, it is proved that the
uniform distribution is universally optimal for a class of trigonometric
regression models with a broad class of covariance kernels and that the arcsine
distribution is universally optimal for the polynomial regression model with
correlation structure defined by the logarithmic potential. To the best
knowledge of the authors these findings provide the first explicit results on
optimal designs for regression models with correlated observations, which are
not restricted to the location scale model.


title: e-MERLIN resolves Betelgeuse at wavelength 5 cm

abstract:
  Convection, pulsation and magnetic fields have all been suggested as
mechanisms for the transport of mass and energy from the optical photosphere of
red supergiants, out to the region where the stellar wind is launched. We
imaged the red supergiant Betelgeuse at 0.06-0.18 arcsec resolution, using
e-MERLIN at 5.5--6.0 GHz, with a sensitivity of ~0.01 mJy/beam. Most of the
radio emission comes from within an ellipse (0.235x0.218) arcsec^2 (~5x the
optical radius), with a flux density of 1.62 mJy, giving an average brightness
temperature ~1250 K. This radio photosphere contains two hotspots of 0.53 and
0.79 mJy/beam, separated by 90 milli-arcsec, with brightness temperatures
5400+/-600 K and 3800+/-500 K. Similar hotspots, at more than double the
distance from the photosphere of those seen in any other regime, were detected
by the less-sensitive `old' MERLIN in 1992, 1995 and 1996 and many exceed the
photospheric temperature of 3600 K. Such brightness temperatures are high
enough to emanate from pockets of chromospheric plasma. Other possibilities
include local shock heating, the convective dredge-up of hot material or
exceptionally cool, low density regions, transparent down to the hottest layer
at ~40 milliarcsec radius. We also detect an arc 0.2--0.3 arcsec to the SW,
brightness temperature ~150 K, in a similar direction to extensions seen on
both smaller and larger scales in the infra-red and in CO at mm wavelengths.
These preliminary results will be followed by further e-MERLIN, VLA and ALMA
observations to help resolve the problem of mass elevation from 1 to 10 R* in
red supergiants.


title: A Model Theory Approach to Structural Limits

abstract:
  The goal of this paper is to unify two lines in a particular area of graph
limits. First, we generalize and provide unified treatment of various graph
limit concepts by means of a combination of model theory and analysis. Then, as
an example, we generalize limits of bounded degree graphs from subgraph testing
to finite model testing.


title: Germes de feuilletages pr\'esentables du plan complexe

abstract:
  Let F be a germ of a singular foliation of the complex plane. Assuming that F
is a generalized curve D. Marin and J.-F. Mattei proved the incompressibility
of the foliation in a neighborhood from which a finite set of analytic curves
is removed. We show in the present work that this hypothesis cannot be eluded
by building examples of foliations, reduced after one blow-up, for which the
property does not hold. Even if we manage to prove that the individual
saddle-node foliation is incompressible, their leaves not retracting
tangentially on the boundary of the domain of definition forbids a
generalization of Marin--Mattei's construction. We finally characterize those
foliations for which the construction of Marin--Mattei's monodromy can be
carried out.


title:
"Systemic Nonlocality" from Changing Constraints on Sub-Quantum
  Kinematics

abstract:
  In a new approach to explain double-slit interference "from the single
particle perspective" via "systemic nonlocality", we answer the question of how
a particle going through one slit can "know" about the state of the other slit.
We show that this comes about by changed constraints on assumed classical
sub-quantum currents, which we have recently employed to derive probability
distributions and Bohm-type trajectories in standard double-slit interference
on the basis of a modern, 21st century classical physics. Despite claims in the
literature that this scenario is to be described by a dynamical nonlocality
that could best be understood in the framework of the Heisenberg picture
(Tollaksen et al., 2010), we show that an explanation can be cast within the
framework of the intuitively appealing Schroedinger picture as well. We refer
neither to potentials nor to a "quantum force" or some other dynamics, but show
that a "systemic nonlocality" may be obtained as a phenomenon that emerges from
an assumed sub-quantum kinematics, which is manipulated only by changing its
constraints as determined by the changes of the apparatus. Consequences are
discussed with respect to the prohibition of superluminal signaling by standard
relativity theory.


title:
A Note on Connected Dominating Set in Graphs Without Long Paths And
  Cycles

abstract:
  The ratio of the connected domination number, $\gamma_c$, and the domination
number, $\gamma$, is strictly bounded from above by 3. It was shown by
Zverovich that for every connected $(P_5,C_5)$-free graph, $\gamma_c = \gamma$.
  In this paper, we investigate the interdependence of $\gamma$ and $\gamma_c$
in the class of $(P_k,C_k)$-free graphs, for $k \ge 6$. We prove that for every
connected $(P_6,C_6)$-free graph, $\gamma_c \le \gamma + 1$ holds, and there is
a family of $(P_6,C_6)$-free graphs with arbitrarily large values of $\gamma$
attaining this bound. Moreover, for every connected $(P_8,C_8)$-free graph,
$\gamma_c / \gamma \le 2$, and there is a family of $(P_7,C_7)$-free graphs
with arbitrarily large values of $\gamma$ attaining this bound. In the class of
$(P_9,C_9)$-free graphs, the general bound $\gamma_c / \gamma \le 3$ is
asymptotically sharp.


title:
Role of electron-electron interference in ultrafast time-resolved
  imaging of electronic wavepackets

abstract:
  Ultrafast time-resolved x-ray scattering is an emerging approach to image the
dynamical evolution of the electronic charge distribution during complex
chemical and biological processes in real-space and real-time. Recently, the
differences between semiclassical and quantum-electrodynamical (QED) theory of
light-matter interaction for scattering of ultrashort x-ray pulses from the
electronic wavepacket were formally demonstrated and visually illustrated by
scattering patterns calculated for an electronic wavepacket in atomic hydrogen
[Proc. Natl. Acad. Sci. U.S.A., {\bf 109}, 11636 (2012)]. In this work, we
present a detailed analysis of time-resolved x-ray scattering from a sample
containing a mixture of non-stationary and stationary electrons within both the
theories. In a many-electron system, the role of scattering interference
between a non-stationary and several stationary electrons to the total
scattering signal is investigated. In general, QED and semiclassical theory
provide different results for the contribution from the scattering
interference, which depends on the energy resolution of the detector and the
x-ray pulse duration. The present findings are demonstrated by means of a
numerical example of x-ray TRI for an electronic wavepacket in helium. It is
shown that the time-dependent scattering interference vanishes within
semiclassical theory and the corresponding patterns are dominated by the
scattering contribution from the time-independent interference, whereas the
time-dependent scattering interference contribution does not vanish in the QED
theory and the patterns are dominated by the scattering contribution from the
non-stationary electron scattering.

categories: physics.atom-ph cond-mat.mes-hall physics.atm-clus physics.chem-ph


title:
CoMP Meets Smart Grid: A New Communication and Energy Cooperation
  Paradigm

abstract:
  In this paper, we pursue a unified study on smart grid and coordinated
multi-point (CoMP) enabled wireless communication by investigating a new joint
communication and energy cooperation approach. We consider a practical CoMP
system with clustered multiple-antenna base stations (BSs) cooperatively
communicating with multiple single-antenna mobile terminals (MTs), where each
BS is equipped with local renewable energy generators to supply power and also
a smart meter to enable two-way energy flow with the grid. We propose a new
energy cooperation paradigm, where a group of BSs dynamically share their
renewable energy for more efficient operation via locally injecting/drawing
power to/from an aggregator with a zero effective sum-energy exchanged. Under
this new energy cooperation model, we consider the downlink transmission in one
CoMP cluster with cooperative zero-forcing (ZF) based precoding at the BSs. We
maximize the weighted sum-rate for all MTs by jointly optimizing the transmit
power allocations at cooperative BSs and their exchanged energy amounts subject
to a new type of power constraints featuring energy cooperation among BSs with
practical loss ratios. Our new setup with BSs' energy cooperation generalizes
the conventional CoMP transmit optimization under BSs' sum-power or
individual-power constraints. Finally, we validate our results by simulations
under various practical setups, and show that the proposed joint communication
and energy cooperation scheme substantially improves the downlink throughput of
CoMP systems powered by smart grid and renewable energy, as compared to other
suboptimal designs without communication and/or energy cooperation.


title:
Nodal gap structure in Fe-based superconductors due to the competition
  between orbital and spin fluctuations

abstract:
  To understand the origin of the nodal gap structure realized in
BaFe$_2$(As,P)$_2$, we study the three-dimensional gap structure based on the
three-dimensional ten-orbital Hubbard model with quadrupole interaction. In
this model, strong spin and orbital fluctuations develop by using the
random-phase-approximation. By solving the Eliashberg gap equation, we obtain
the fully-gapped s-wave state with (without) sign reversal between hole-like
and electron-like Fermi surfaces due to strong spin (orbital) fluctuations, so
called the $s_\pm$-wave ($s_{++}$-wave) state. When both spin and orbital
fluctuations strongly develop, which will be realized near the orthorhombic
phase, we obtain the nodal s-wave state in the crossover region between
$s_{++}$-wave and $s_\pm$-wave states. The obtained nodal s-wave state
possesses the loop-shape nodes on electron-like Fermi surfaces, due to the
competition between attractive and repulsive interactions in k-space. In
contrast, the SC gaps on the hole-like Fermi surfaces are fully-gapped due to
orbital fluctuations. The present study explains the main characters of the
anisotropic gap structure in BaFe$_2$(As,P)$_2$ observed experimentally.


title:
Conical Fireballs, Cannonballs, And Jet-Breaks In The Afterglows Of
  Gamma Ray Bursts

abstract:
  The 'jet-break' in the X-ray afterglow of gamma ray bursts (GRBs) appears to
be correlated to other properties of the X-ray afterglow and the prompt gamma
ray emission, but the correlations are at odds with those predicted by the
conical fireball model of GRBs. The correlations are in good agreement,
however, with those predicted by the Cannonball model of GRBs.


title: Inferring Social Rank in an Old Assyrian Trade Network

abstract:
  We present work in jointly inferring the unique individuals as well as their
social rank within a collection of letters from an Old Assyrian trade colony in
K\"ultepe, Turkey, settled by merchants from the ancient city of Assur for
approximately 200 years between 1950-1750 BCE, the height of the Middle Bronze
Age. Using a probabilistic latent-variable model, we leverage pairwise social
differences between names in cuneiform tablets to infer a single underlying
social order that best explains the data we observe. Evaluating our output with
published judgments by domain experts suggests that our method may be used for
building informed hypotheses that are driven by data, and that may offer
promising avenues for directed research by Assyriologists.


title:
The subset argument and consistency of MLE in GLMM: Answer to an open
  problem and beyond

abstract:
  We give answer to an open problem regarding consistency of the maximum
likelihood estimators (MLEs) in generalized linear mixed models (GLMMs)
involving crossed random effects. The solution to the open problem introduces
an interesting, nonstandard approach to proving consistency of the MLEs in
cases of dependent observations. Using the new technique, we extend the results
to MLEs under a general GLMM. An example is used to further illustrate the
technique.


title:
On the convergence rate improvement of a primal-dual splitting algorithm
  for solving monotone inclusion problems

abstract:
  We present two modified versions of the primal-dual splitting algorithm
relying on forward-backward splitting proposed in \cite{vu} for solving
monotone inclusion problems. Under strong monotonicity assumptions for some of
the operators involved we obtain for the sequences of iterates that approach
the solution orders of convergence of O(1/n) and O(\omega^n), for $\omega \in
(0,1)$, respectively. The investigated primal-dual algorithms are fully
decomposable, in the sense that the operators are processed individually at
each iteration. We also discuss the modified algorithms in the context of
convex optimization problems and present numerical experiments in image
processing and support vector machines classification.


title:
Optogenetic manipulation of neural activity in C. elegans: from synapse
  to circuits and behavior

abstract:
  The emerging field of optogenetics allows for optical activation or
inhibition of neurons and other tissue in the nervous system. In 2005
optogenetic proteins were expressed in the nematode C. elegans for the first
time. Since then, C. elegans has served as a powerful platform upon which to
conduct optogenetic investigations of synaptic function, circuit dynamics and
the neuronal basis of behavior. The C. elegans nervous system, consisting of
302 neurons, whose connectivity and morphology has been mapped completely,
drives a rich repertoire of behaviors that are quantifiable by video
microscopy. This model organism's compact nervous system, quantifiable
behavior, genetic tractability and optical accessibility make it especially
amenable to optogenetic interrogation. Channelrhodopsin-2 (ChR2), halorhodopsin
(NpHR/Halo) and other common optogenetic proteins have all been expressed in C.
elegans. Moreover recent advances leveraging molecular genetics and patterned
light illumination have now made it possible to target photoactivation and
inhibition to single cells and to do so in worms as they behave freely. Here we
describe techniques and methods for optogenetic manipulation in C. elegans. We
review recent work using optogenetics and C. elegans for neuroscience
investigations at the level of synapses, circuits and behavior.


title: 2013 Unit Vectors in the Plane

abstract:
  Given a norm on the plane and 2013 unit vectors in this norm, there is a
signed sum of these vectors whose norm is at most one.


title: On Addition Formulae for Sigma Functions of Telescopic Curves

abstract:
  A telescopic curve is a certain algebraic curve defined by $m-1$ equations in
the affine space of dimension $m$, which can be a hyperelliptic curve and an
$(n,s)$ curve as a special case. We extend the addition formulae for sigma
functions of $(n,s)$ curves to those of telescopic curves. The expression of
the prime form in terms of the derivative of the sigma function is also given.


title:
Dispersive evaluation of the second-class amplitude
  $\tau\to\eta\pi\nu_\tau$ in the standard model

abstract:
  We reevaluate the two form factors relevant for the $\eta\pi$ second-class
$\tau$ decay mode, making systematic use of analyticity, unitarity, combined
with updated inputs to the NLO chiral constraints. We focus, in particular, on
the shape of the $\rho$ resonance peak which is a background-free signature of
a second-class current. Its dispersive construction requires the
$\eta\pi\to\pi\pi$ scattering amplitude which we derive from a family of
Khuri-Treiman equations solutions constrained with accurate recent results on
the $\eta\to3\pi$ Dalitz plot.


title: Euclidean random matrices and their applications in physics

abstract:
  We review the state of the art of the theory of Euclidean random matrices,
focusing on the density of their eigenvalues. Both Hermitian and non-Hermitian
matrices are considered and links with simpler, standard random matrix
ensembles are established. We discuss applications of Euclidean random matrices
to contemporary problems in condensed matter physics, optics, and quantum
chaos.

categories: math-ph cond-mat.dis-nn math.MP physics.optics


title: On toral eigenfunctions and the random wave model

abstract:
  The purpose of this Note is to provide a deterministic implementation of the
random wave model for the number of nodal domains in the context of the
two-dimensional torus. The approach is based on recent work due to Nazarov and
Sodin and arithmetical properties of lattice points on circles.


title: Exclusive $p p \to p p \pi^{0}$ reaction at high energies

abstract:
  The amplitudes for the $p p \to p p \pi^{0}$ process applicable at high
energy are discussed in detail. Both diffractive bremsstrahlung
(Drell-Hiida-Deck--type model), photon-photon and photon-omega exchange
mechanisms are included in the calculation. Large cross sections of the order
of mb are predicted. The corresponding differential cross sections in
rapidities and transverse momenta of outgoing protons and pions as well as
relative azimuthal angle between outgoing protons are calculated for RHIC and
LHC energies. The hadronic bremsstrahlung contributions dominate at large
(forward, backward) pion rapidities. The diffractive nonresonant background
contributes at small $\pi^0 p$ invariant mass and could be therefore
misinterpreted as the Roper resonance. We predict strong dependence of the
slope in $t$ (squared four-momentum transfer between ingoing and outgoing
proton) on the mass of the supplementary excited $\pi^{0}p$ system. At high
energies and midrapidities, the photon-photon contribution dominates over the
diffractive components, however, the corresponding cross section is rather
small. The photon-odderon and odderon-photon contributions are included in
addition and first estimates (upper limits) of their contributions to rapidity
and transverse momentum distribution of neutral pions are presented. We suggest
a search for the odderon contribution at midrapidity and at $p_{\perp,\pi^{0}}
\sim$ 0.5 GeV. Our predictions are ready for verification at RHIC and LHC. The
bremsstrahlung mechanisms discussed here contribute also to the $pp \to p(n
\pi^{+})$ reaction. Both channels give a sizable contribution to the low-mass
single diffractive cross section and must be included in extrapolating the
measured experimental single diffractive cross section.


title:
Decomposition numbers for Brauer algebras of type G(m,p,n) in
  characteristic zero

abstract:
  We introduce Brauer algebras associated to complex reflection groups of type
$G(m,p,n)$, and study their representation theory via Clifford theory. In
particular, we determine the decomposition numbers of these algebras in
characteristic zero.


title:
Double-exchange theory of ferroelectric polarization in orthorhombic
  manganites with twofold periodic magnetic texture

abstract:
  We argue that many aspects of improper ferroelectric activity in orthorhombic
manganites can be rationalized by considering the limit of infinite
intra-atomic splitting between the majority- and minority-spin states (or the
double exchange limit), which reduces the problem to the analysis of a spinless
double exchange (DE) Hamiltonian. We apply this strategy to the low-energy
model, derived from the first-principles calculations, and combine it with the
Berry-phase theory of electric polarization. We start with the simplest
two-orbital model, describing the behavior of the eg bands, and apply it to the
E-type antiferromagnetic (AFM) phase, which in the DE limit effectively breaks
up into one-dimensional zigzag chains. We derive an analytical expression for
the electronic polarization (Pel) and explain how it depends on the orbital
ordering and the energy splitting Delta between eg states. Then, we evaluate
parameters of this model, starting from a more general five-orbital model for
all Mn 3d bands and constructing a new downfolded model for the eg bands. From
the analysis of these parameters, we conclude that the behavior of Pel in
realistic manganites corresponds to the limit of large Delta. We further
utilize this property in order to derive an analytical expression for Pel in a
general two-fold periodic magnetic texture, based on the five-orbital model and
the perturbation-theory expansion for the Wannier functions in the first order
of 1/Delta. This expression explains the functional dependence of Pel on the
relative directions of spins. Furthermore, it suggests that Pel is related to
the asymmetry of the transfer integrals, which should simultaneously have
symmetric and antisymmetric components. Finally, we explain how the
polarization can be switched between orthorhombic directions a and c by
inverting the zigzag AFM texture in every second ab plane.


title:
Universal breaking point asymptotic for energy spectrum of Riemann waves
  in weakly nonlinear non-dispersive media

abstract:
  In this Letter we study the form of the energy spectrum of Riemann waves in
weakly nonlinear non-dispersive media. For quadratic and cubic nonlinearity we
demonstrate that the deformation of an Riemann wave over time yields an
exponential energy spectrum which turns into power law asymptotic with the
slope being approximately -8/3 at the last stage of evolution before breaking.
We argue, that this is the universal asymptotic behaviour of Riemann waves in
any nonlinear non-dispersive medium at the point of breaking. The results
reported in this Letter can be used in various non-dispersive media, e.g.
magneto-hydro dynamics, physical oceanography, nonlinear acoustics.


title: Position space formulation for Dirac fermions on honeycomb lattice

abstract:
  We study how to construct Dirac fermion defined on the honeycomb lattice in
position space. Starting from the nearest neighbor interaction in tight binding
model, we show that the Hamiltonian is constructed by kinetic term and second
derivative term of three flavor Dirac fermions in which one flavor has a mass
of cutoff order and the other flavors are massless. In this formulation the
structure of the Dirac point is simplified so that its uniqueness can be easily
shown even if we consider the next-nearest neighbor interaction. We also show
the chiral symmetry at finite lattice spacing, which protects the masslessness
of the Dirac fermion, and discuss the analogy with the staggered fermion
formulation.


title: The period length of Euler's number e

abstract:
  Let s_k/t_k, k>= 0, be the convergents of the continued fraction expansion of
a real number x. We investigate the sequence of Jacobi symbols (s_k/t_k), k>=
0. We show that this sequence is purely periodic with shortest possible period
length 24 for x=e=2.718281... and shortest possible period length 40 for x=e^2.
Further, we make the first steps towards a general theory of such sequences of
Jacobi symbols. For instance, we show that there are uncountably many numbers x
such that this sequence has the period 1 (of length 1), and that every natural
number L actually occurs as the shortest possible period length of some x.


title: Anharmonicity due to Electron-Phonon Coupling in Magnetite

abstract:
  We present the results of inelastic x-ray scattering for magnetite and
analyze the energies and spectral widths of the phonon modes with different
symmetries in a broad range of temperature 125<T<293 K. The phonon modes with
X_4 and Delta_5 symmetries broaden in a nonlinear way with decreasing
temperature when the Verwey transition is approached. It is found that the
maxima of phonon widths occur away from high-symmetry points which indicates
the incommensurate character of critical fluctuations. Strong phonon
anharmonicity induced by electron-phonon coupling is discovered within ab
initio calculations which take into account local Coulomb interactions at Fe
ions. It (i) explains observed anomalous phonon broadening, and (ii)
demonstrates that the Verwey transition is a cooperative phenomenon which
involves a wide spectrum of phonons coupled to charge fluctuations condensing
in the low-symmetry phase.


title: Cosmic ray anisotropies to 5 PeV

abstract:
  Several large cosmic ray (CR) detectors have recently provided data on the
arrival directions of CR, which taken together with previous data recorded over
many decades allow the amplitgude and phase of the first harmonic to be derived
with reasonable precision and up to higher energies. We find a high degree of
consistency amongst the various measurements. The new data indicate that at an
energy above ~0.1 PeV a change of the CR anisotropy sets in. The amplitude of
the first harmonic, which rises to 3 TeV, then diminishes and begins to rise
again. The direction of the phase also changes to the opposite one. A measure
of understanding follows from the use of two-dimensional maps of CR excesses
over the mean background. When the energy of CR approaches the PeV region, the
excess of CR moves from the Galactic Anti-Centre to the opposite direction of
the Galactic Centre. The possible role of such potential CR sources as the
supernovae Monogem Ring and Vela, which could help to explain some of the
observed results, is discussed.


title:
\beta-function for the Higgs self-interaction in the Standard Model at
  three-loop level

abstract:
  We analytically compute the QCD, electroweak, Higgs and third generation
Yukawa contributions to the \beta-function for the Higgs self-coupling as well
as for the Higgs mass parameter in the unbroken phase of the Standard Model at
three-loop level.


title: Three-dimensional Brownian motion and the golden ratio rule

abstract:
  Let $X=(X_t)_{t\ge0}$ be a transient diffusion process in $(0,\infty)$ with
the diffusion coefficient $\sigma>0$ and the scale function $L$ such that
$X_t\rightarrow\infty$ as $t\rightarrow \infty$, let $I_t$ denote its running
minimum for $t\ge0$, and let $\theta$ denote the time of its ultimate minimum
$I_{\infty}$. Setting $c(i,x)=1-2L(x)/L(i)$ we show that the stopping time
\[\tau_*=\inf\{t\ge0\vert X_t\ge f_*(I_t)\}\] minimizes
$\mathsf{E}(\vert\theta-\tau\vert-\theta)$ over all stopping times $\tau$ of
$X$ (with finite mean) where the optimal boundary $f_*$ can be characterized as
the minimal solution to
\[f'(i)=-\frac{\sigma^2(f(i))L'(f(i))}{c(i,f(i))[L(f(i))-L(i)]}\int_i^{f(i)}\frac{c_i'(i,y)[L(y)
-L(i)]}{\sigma^2(y)L'(y)}\,dy\] staying strictly above the curve
$h(i)=L^{-1}(L(i)/2)$ for $i>0$. In particular, when $X$ is the radial part of
three-dimensional Brownian motion, we find that \[\tau_
*=\inf\biggl\{t\ge0\Big\vert\frac{X_t-I_t}{I_t}\ge\varphi\biggr\},\] where
$\varphi=(1+\sqrt{5})/2=1.61\ldots$ is the golden ratio. The derived results
are applied to problems of optimal trading in the presence of bubbles where we
show that the golden ratio rule offers a rigorous optimality argument for the
choice of the well-known golden retracement in technical analysis of asset
prices.


title: Toward Optimal Stratification for Stratified Monte-Carlo Integration

abstract:
  We consider the problem of adaptive stratified sampling for Monte Carlo
integration of a noisy function, given a finite budget n of noisy evaluations
to the function. We tackle in this paper the problem of adapting to the
function at the same time the number of samples into each stratum and the
partition itself. More precisely, it is interesting to refine the partition of
the domain in area where the noise to the function, or where the variations of
the function, are very heterogeneous. On the other hand, having a (too) refined
stratification is not optimal. Indeed, the more refined the stratification, the
more difficult it is to adjust the allocation of the samples to the
stratification, i.e. sample more points where the noise or variations of the
function are larger. We provide in this paper an algorithm that selects online,
among a large class of partitions, the partition that provides the optimal
trade-off, and allocates the samples almost optimally on this partition.


title:
In search for the pairing glue in cuprates by non-equilibrium optical
  spectroscopy

abstract:
  In strongly correlated materials the electronic and optical properties are
significantly affected by the coupling of fermionic quasiparticles to different
degrees of freedom, such as lattice vibrations and bosonic excitations of
electronic origin. Broadband ultrafast spectroscopy is emerging as the premier
technique to unravel the subtle interplay between quasiparticles and electronic
or phononic collective excitations, by their different characteristic
timescales and spectral responses. By investigating the femtosecond dynamics of
the optical properties of Y-Bi2212 crystals over the 0.5-2 eV energy range, we
disentangle the electronic and phononic contributions to the generalized
electron-boson Eliashberg function, showing that the spectral distribution of
the electronic excitations, such as spin fluctuations and current loops, and
the strength of their interaction with quasiparticles can account for the high
critical temperature of the superconducting phase transition. Finally, we
discuss how the use of this technique can be extended to the underdoped region
of the phase diagram of cuprates, in which a pseudogap in the quasiparticle
density of states opens. The microscopic modeling of the interaction of
ultrashort light pulses with unconventional superconductors will be one of the
key challenges of the next-years materials science, eventually leading to the
full understanding of the role of the electronic correlations in controlling
the dynamics on the femtosecond timescale.


title:
The gap probabilities of the tacnode, Pearcey and Airy point processes,
  their mutual relationship and evaluation

abstract:
  We express the gap probabilities of the tacnode process as the ratio of two
Fredholm determinants; the denominator is the standard Tracy-Widom
distribution, while the numerator is the Fredholm determinant of a very
explicit kernel constructed with Airy functions and exponentials. The formula
allows us to apply the theory of numerical evaluation of Fredholm determinants
and thus produce numerical results for the gap probabilities. In particular we
investigate numerically how, in different regimes, the Pearcey process
degenerates to the Airy one, and the tacnode degenerates to the Pearcey and
Airy ones.


title:
Thermally excited spin waves in a nano-structure: thermal gradient vs.
  constant temperature

abstract:
  Using micromagnetic simulations, we have investigated spin dynamics in a
nanostructure in the presence of thermal fluctuations. In particular, we have
studied the effects of a uniform temperature and of a uniform thermal gradient.
In both cases, the stochastic field leads to an increase of the precession
angle of the magnetization, and to a mild decreas of the linewidth of the
resonance peaks. Our results indicate that the Gilbert damping parameter plays
the role of control parameter for the amplification of spin waves.


title:
Application of Quantum Process Calculus to Higher Dimensional Quantum
  Protocols

abstract:
  We describe the use of quantum process calculus to describe and analyze
quantum communication protocols, following the successful field of formal
methods from classical computer science. We have extended the quantum process
calculus to describe d-dimensional quantum systems, which has not been done
before. We summarise the necessary theory in the generalisation of quantum
gates and Bell states and use the theory to apply the quantum process calculus
CQP to quantum protocols, namely qudit teleportation and superdense coding.


title:
A localization theorem and boundary regularity for a class of degenerate
  Monge Ampere equations

abstract:
  We consider degenerate Monge-Ampere equations of the type $$\det D^2 u= f
\quad \{in $\Om$}, \quad \quad f \sim \, d_{\p \Om}^\alpha \quad \{near $\p
\Om$,}$$ where $d_{\p \Om}$ represents the distance to the boundary of the
domain $\Om$ and $\alpha>0$ is a positive power. We obtain $C^2$ estimates at
the boundary under natural conditions on the boundary data and the right hand
side. Similar estimates in two dimensions were obtained by J.X. Hong, G. Huang
and W. Wang.