title: Eugene Paul Wigner's Nobel Prize

abstract:
  In 1963, Eugene Paul Wigner was awarded the Nobel Prize in Physics for his
contributions to the theory of the atomic nucleus and the elementary particles,
particularly through the discovery and application of fundamental symmetry
principles. There are no disputes about this statement. On the other hand,
there still is a question of why the statement did not mention Wigner's 1939
paper on the Lorentz group, which was regarded by Wigner and many others as his
most important contribution in physics. By many physicists, this paper was
regarded as a mathematical exposition having nothing to do with physics.
However, it has been more than one half century since 1963, and it is of
interest to see what progress has been made toward understanding physical
implications of this paper and its historical role in physics. Wigner in his
1963 paper defined the subgroups of the Lorentz group whose transformations do
not change the four-momentum of a given particle, and he called them the little
groups. Thus, Wigner's little groups are for internal space-time symmetries of
particles in the Lorentz-covariant world. Indeed, this subgroup can explain the
electron spin and spins of other massive particles. However, for massless
particles, there was a gap between his little group and electromagnetic waves
derivable Maxwell's equations. This gap was not completely removed until 1990.
The purpose of this report is to review the stormy historical process in which
this gap is cleared. It is concluded that Wigner's little groups indeed can be
combined into one Lorentz-covariant formula which can dictate the symmetry of
the internal space-time time symmetries of massive and massless particles in
the Lorentz covariant world, just like Einstein's energy-momentum relation
applicable to both slow and massless particles.


title:
Combining Generative and Discriminative Neural Networks for Sleep Stages
  Classification

abstract:
  Sleep stages pattern provides important clues in diagnosing the presence of
sleep disorder. By analyzing sleep stages pattern and extracting its features
from EEG, EOG, and EMG signals, we can classify sleep stages. This study
presents a novel classification model for predicting sleep stages with a high
accuracy. The main idea is to combine the generative capability of Deep Belief
Network (DBN) with a discriminative ability and sequence pattern recognizing
capability of Long Short-term Memory (LSTM). We use DBN that is treated as an
automatic higher level features generator. The input to DBN is 28 "handcrafted"
features as used in previous sleep stages studies. We compared our method with
other techniques which combined DBN with Hidden Markov Model (HMM).In this
study, we exploit the sequence or time series characteristics of sleep dataset.
To the best of our knowledge, most of the present sleep analysis from
polysomnogram relies only on single instanced label (nonsequence) for
classification. In this study, we used two datasets: an open data set that is
treated as a benchmark; the other dataset is our sleep stages dataset
(available for download) to verify the results further. Our experiments showed
that the combination of DBN with LSTM gives better overall accuracy 98.75\%
(Fscore=0.9875) for benchmark dataset and 98.94\% (Fscore=0.9894) for MKG
dataset. This result is better than the state of the art of sleep stages
classification that was 91.31\%.


title: Gauge Unification from Split Supersymmetric String Models

abstract:
  We discuss the unification of gauge coupling constants in non-supersymmetric
open string vacua that possess the properties of Split Supersymmetry, namely
the Standard Model with Higgsinos at low energies and where the Standard model
spectrum is always accompanied by right handed neutrinos. These vacua achieve
partial unification of two out of three (namely SU(3)$_c$, SU(2), U(1)) running
gauge couplings, possess massive gauginos and light Higgsinos at low energies
and also satisfy $sin^2\theta_w (M_s) = 3/8$. These vacua are based on four
dimensional orbifold $Z_3 \times Z_3$ compactifications of string IIA
orientifolds with D6-branes intersecting at angles, where the (four
dimensional) chiral fermions of the Standard Model appear as opens strings
streching between the intersections of seven dimensional objects the so called
D6-branes.


title:
Effective Hamiltonian theory for nonreciprocal light propagation in
  magnetic Rashba conductor

abstract:
  Rashba spin-orbit interaction leads to a number of electromagnetic
cross-correlation effects by inducing a mixing of electric and magnetic degrees
of freedom. In this study, we investigate the optical properties of a magnetic
Rashba conductor by deriving an effective Hamiltonian based on an
imaginary-time path-integral formalism. We show that the effective Hamiltonian
can be described in terms of toroidal and quadrupole moments, as has been
argued in the case of insulator multiferroics. The toroidal moment turns out to
coincide with the spin gauge field induced by the Rashba field. It causes
Doppler shift by inducing intrinsic spin current, resulting in anisotropic
light propagation (directional dichroism) irrespective of the polarization. The
quadrupole moment on the other hand results in a magneto-optical phenomenon
such as a Faraday effect for circularly-polarized waves.


title: Thermodynamical and dynamical properties of Charged BTZ Black Holes

abstract:
  We investigate the spacetime properties of BTZ black holes in the presence of
the Maxwell field and Born-Infeld field and find rich properties in the
spacetime structures when the model parameters are varied. Employing the
Landau-Lifshitz theory, we examine the thermodynamical phase transition in the
charged BTZ black holes. We further study the dynamical perturbation in the
background of the charged BTZ black holes and find different properties in the
dynamics when the thermodynamical phase transition occurs.


title:
Global-in-time smoothing effects for Schr\"odinger equations with
  inverse-square potentials

abstract:
  The purpose of this note is to prove global-in-time smoothing effects for the
Schr\"odinger equation with potentials exhibiting critical singularity. A
typical example of admissible potentials is the inverse-square potential
$a|x|^{-2}$ with $a>-(n-2)^2/4$. This particularly gives an affirmative answer
to a question raised by Bui-D'Ancona-Duong-Li-Ly [4]. The proof employs a
uniform resolvent estimate proved by Barcel\'o-Vega-Zubeldia [1] and an
abstract perturbation method by Bouclet-Mizutani [3].


title:
An improved d-band model of the catalytic activity of magnetic
  transition metal surfaces

abstract:
  The d-band center model of Hammer and N{\o}rskov is widely used in
understanding and predicting catalytic activity on transition metal (TM)
surfaces. Here, we demonstrate that this model is inadequate for capturing the
complete catalytic activity of the magnetically polarized TM surfaces and
propose its generalization. We validate the generalized model through
comparison of adsorption energies of the NH$_3$ molecule on the surfaces of 3d
TMs (V, Cr, Mn, Fe, Co, Ni, Cu and Zn) determined with spin-polarized density
functional theory (DFT)-based methods with the predictions of our model.
Compared to the conventional d-band model, where the nature of the
metal-adsorbate interaction is entirely determined through the energy and the
occupation of the d-band center, we emphasize that for the surfaces with high
spin polarization, the metal-adsorbate system can be stabilized through a
competition of the spin-dependent metal-adsorbate interactions.


title:
On Limiting Distribution of Quasi-Posteriors under Partial
  Identification

abstract:
  We establish the limiting distribution (in total variation) of the quasi
posteriors based on moment conditions, which only partially identify the
parameters of interest. Some examples are discussed.


title: Flat bands and Dirac cones in breathing lattices

abstract:
  In breathing pyrochlores and kagomes, couplings between neighbouring
tetrahedra and triangles are free to differ. Breathing lattices thus offer the
possibility to explore a different facet of the rich physics of these systems.
Here we consider nearest-neighbour classical Heisenberg interactions, both
ferromagnetic and antiferromagnetic, and study how the anisotropy of breathing
lattices modifies the mode spectrum of pyrochlore and kagome systems. The
nature and degeneracy of the flat bands are shown to be preserved for any value
of the anisotropy. These flat bands can coexist with Dirac nodes at the
$\Gamma$ point when the model becomes particle-hole symmetric. We also derive
the nature of the ground state for the breathing kagome lattice, which bears a
spontaneous chirality when neighbouring triangles are alternatively
ferromagnetic and antiferromagnetic.


title:
Variable-Length Coding with Cost Allowing Non-Vanishing Error
  Probability

abstract:
  We derive a general formula of the minimum achievable rate for
fixed-to-variable length coding with a regular cost function by allowing the
error probability up to a constant $\varepsilon$. For a fixed-to-variable
length code, we call the set of source sequences that can be decoded without
error the dominant set of source sequences. For any two regular cost functions,
it is revealed that the dominant set of source sequences for a code attaining
the minimum achievable rate with a cost function is also the dominant set for a
code attaining the minimum achievable rate with the other cost function. We
also give a general formula of the second-order minimum achievable rate.


title: Can we classify complete metric spaces up to isometry?

abstract:
  We survey some old and new results concerning the classification of complete
metric spaces up to isometry, a theme initiated by Gromov, Vershik and others.
All theorems concerning separable spaces appeared in various papers in the last
twenty years: here we tried to present them in a unitary and organic way,
sometimes with new and/or simplified proofs. The results concerning
non-separable spaces (and, to some extent, the setup and techniques used to
handle them) are instead new, and suggest new lines of investigation in this
area of research.


title: On the norm of a random jointly exchangeable matrix

abstract:
  In this note, we show that the norm of an $n\times n$ random jointly
exchangeable matrix with zero diagonal can be estimated in terms of the norm of
its $n/2\times n/2$ submatrix located in the top right corner. As a
consequence, we prove a relation between the second largest singular values of
a random matrix with constant row and column sums and its top right $n/2\times
n/2$ submatrix. The result has an application to estimating the spectral gap of
random undirected $d$-regular graphs in terms of the second singular value of
{\it directed} random graphs with predefined degree sequences.


title: Effective field theory for pions and a dilatonic meson

abstract:
  Numerical simulations of QCD-like theories which are chirally broken but
exhibit a very small beta function reveal a flavor-singlet scalar, or
"dilatonic meson," which is much lighter than any other states except pions. We
develop a systematic low-energy expansion for the pions and the dilatonic
meson, in which the presence of the latter is attributed to an approximate
scale symmetry. In order to justify the power counting we invoke the Veneziano
limit, in which the number of flavors $N_f$ in the fundamental representation
grows in proportion with the number of colors $N_c$, while the ratio $N_f/N_c$
is kept close to, but below, the critical value where the conformal window is
entered.


title: A general lower bound for collaborative tree exploration

abstract:
  We consider collaborative graph exploration with a set of $k$ agents. All
agents start at a common vertex of an initially unknown graph and need to
collectively visit all other vertices. We assume agents are deterministic,
vertices are distinguishable, moves are simultaneous, and we allow agents to
communicate globally. For this setting, we give the first non-trivial lower
bounds that bridge the gap between small ($k \leq \sqrt n$) and large ($k \geq
n$) teams of agents. Remarkably, our bounds tightly connect to existing results
in both domains.
  First, we significantly extend a lower bound of $\Omega(\log k / \log\log k)$
by Dynia et al. on the competitive ratio of a collaborative tree exploration
strategy to the range $k \leq n \log^c n$ for any $c \in \mathbb{N}$. Second,
we provide a tight lower bound on the number of agents needed for any
competitive exploration algorithm. In particular, we show that any
collaborative tree exploration algorithm with $k = Dn^{1+o(1)}$ agents has a
competitive ratio of $\omega(1)$, while Dereniowski et al. gave an algorithm
with $k = Dn^{1+\varepsilon}$ agents and competitive ratio $O(1)$, for any
$\varepsilon > 0$ and with $D$ denoting the diameter of the graph. Lastly, we
show that, for any exploration algorithm using $k = n$ agents, there exist
trees of arbitrarily large height $D$ that require $\Omega(D^2)$ rounds, and we
provide a simple algorithm that matches this bound for all trees.


title:
Interior Solutions of Fluid Sphere in f(R,T) Gravity Admitting Conformal
  Killing Vectors

abstract:
  We discuss the interior solutions of fluid Sphere in f(R,T) gravity admitting
conformal killing vectors, where R is Ricci scalar and T is trace of energy
momentum tensor. The solutions corresponding to isotropic and anisotropic
configurations have been investigated explicitly. Further, the anisotropic case
has been dealt by the utilization of linear equation of state. The results for
both cases have been interpreted graphically. The equation of state parameter,
integration constants and other parameters of the theory have been chosen to
find the central density equal to standard value of central density of the
compact objects. The energy conditions as well as stability of the solutions
have been investigated in the background of f(R,T) gravity.


title:
On the determination of the He abundance distribution in globular
  clusters from the width of the main sequence

abstract:
  One crucial piece of information to study the origin of multiple stellar
populations in globular clusters, is the range of initial helium abundances
$\Delta{Y}$ amongst the sub-populations hosted by each cluster. These estimates
are commonly obtained by measuring the width in colour of the unevolved main
sequence in an optical colour-magnitude-diagram. The measured colour spread is
then compared with predictions from theoretical stellar isochrones with varying
initial He abundances, to determine $\Delta{Y}$. The availability of UV/optical
magnitudes thanks to the {\sl HST UV Legacy Survey of Galactic GCs} project,
will allow the homogeneous determination of $\Delta{Y}$ for a large Galactic
globular cluster sample. From a theoretical point of view, accurate UV CMDs can
efficiently disentangle the various sub-populations, and main sequence colour
differences in the ACS $F606W-(F606W-F814W)$ diagram allow an estimate of
$\Delta{Y}$. We demonstrate that from a theoretical perspective the
($F606W-F814W$) colour is an extremely reliable He-abundance indicator. The
derivative d$Y$/d($F606W-F814W$), computed at a fixed luminosity along the
unevolved main sequence, is largely insensitive to the physical assumptions
made in stellar model computations, being more sensitive to the choice of the
bolometric correction scale, and is only slightly dependent on the adopted set
of stellar models. From a theoretical point of view the ($F606W-F814W$) colour
width of the cluster main sequence is therefore a robust diagnostic of the
$\Delta{Y}$ range.


title:
Quantum Size Effect Exponential Heat Capacity in 4 nm Natural Nickel
  Nanolattice

abstract:
  Quantum size effect-induced heat capacity of metal nanoparticles at low
temperatures was predicted 79 years ago to be exponential. This, however, has
not been reported until date. In defiance, we demonstrate here observation of
exponentially decaying heat capacity, below 45.2 K, associated with quantum
jumps, exceptionally in 4 nm naturally assembled hexagonal closed packed (hcp)
lattice of nickel nanoparticles; high magnetic fields have negligible effect on
these features. Magnetic susceptibilities in contrast reveal evolution of
quantum size effects with decrease in particle size. They exhibit sharp rise
below about 30 K and vestiges of saturations below 5 K. The former is explained
by Curie-like characteristics of odd electrons while the latter tend towards
the orthogonal even-like case. These characteristics, ascribed to the ensembles
of Ni nanoparticles, will give a new direction in understanding this crucial
thermodynamic phenome-non.


title:
Ischemic Stroke Identification Based on EEG and EOG using 1D
  Convolutional Neural Network and Batch Normalization

abstract:
  In 2015, stroke was the number one cause of death in Indonesia. The majority
type of stroke is ischemic. The standard tool for diagnosing stroke is CT-Scan.
For developing countries like Indonesia, the availability of CT-Scan is very
limited and still relatively expensive. Because of the availability, another
device that potential to diagnose stroke in Indonesia is EEG. Ischemic stroke
occurs because of obstruction that can make the cerebral blood flow (CBF) on a
person with stroke has become lower than CBF on a normal person (control) so
that the EEG signal have a deceleration. On this study, we perform the ability
of 1D Convolutional Neural Network (1DCNN) to construct classification model
that can distinguish the EEG and EOG stroke data from EEG and EOG control data.
To accelerate training process our model we use Batch Normalization. Involving
62 person data object and from leave one out the scenario with five times
repetition of measurement we obtain the average of accuracy 0.86 (F-Score
0.861) only at 200 epoch. This result is better than all over shallow and
popular classifiers as the comparator (the best result of accuracy 0.69 and
F-Score 0.72 ). The feature used in our study were only 24 handcrafted feature
with simple feature extraction process.


title:
Comment on pyramidal structure formation at the interface between III/V
  semiconductors and silicon

abstract:
  GaP/Si(100) is considered as pseudomporphic virtual substrate for III/V-on-Si
integration in order to reduce defects related to polar-on-nonpolar
heteroepitaxy. The atomic structure of the GaP/Si(100) heterointerface is
decisive to yield low defect densities and its dependence on nucleation
conditions is still under debate. Recently, Beyer et al. suggested the
formation of a 'pyramidal' structure as a general mechanism at
polar-on-nonpolar interfaces [A. Beyer et al., Chem. Mat. 28, 3265 (2016)].
However, their DFT studies neglected the dependence of the calculated
interfacial energies on appropriate chemical potentials and their findings are
contradictory to recent and past experimental data.


title: Vector nematicons

abstract:
  Families of soliton pairs, namely vector solitons, are found within the
context of a coupled nonlocal nonlinear Schrodinger system of equations, as
appropriate for modeling beam propagation in nematic liquid crystals. In the
focusing case, bright soliton pairs have been found to exist provided their
amplitudes satisfy a specific condition. In our analytical approach, focused on
the defocusing regime, we rely on a multiscale expansion methods, which reveals
the existence of dark-dark and antidark-antidark solitons, obeying an effective
Korteweg-de Vries equation, as well as dark-bright solitons, obeying an
effective Mel'nikov system. These pairs are discriminated by the sign of a
constant that links all physical parameters of the system to the amplitude of
the stable continuous wave solutions, and, much like the focusing case, the
solitons' amplitudes are linked leading to mutual guiding.


title: Problems 85 and 87 of Birkhoff's "Lattice theory"

abstract:
  We solve problems 85 a(nd 87 from Birkhoff's book "Lattice Theory" (3rd
edition)


title: Birth and Death of Chimera: Interplay of Delay and Multiplexing

abstract:
  The chimera state with co-existing coherent-incoherent dynamics has recently
attracted a lot of attention due to its wide applicability. We investigate
non-locally coupled identical chaotic maps with delayed interactions in the
multiplex network framework and find that an interplay of delay and
multiplexing brings about an enhanced or suppressed appearance of chimera state
depending on the distribution as well as the parity of delay values in the
layers. Additionally, we report a layer chimera state with an existence of one
layer displaying coherent and another layer demonstrating incoherent dynamical
evolution. The rich variety of dynamical behavior demonstrated here can be used
to gain further insight into the real-world networks which inherently possess
such multi-layer architecture with delayed interactions.


title:
Size-induced structural phase transition at ~6.0 nm from mixed fcc-hcp
  to purely fcc structure in monodispersed nickel nanoparticles

abstract:
  We have investigated the core issue of atomic lattices in monodispersed Ni
nanoparticles (NPs) of sizes 3.8 nm to 10.1 nm using detailed analysis of X-ray
diffraction, synchrotron radiation X-ray absorption spectroscopy (XAS) and
magnetization data. This has revealed the very remarkable coexistence of atomic
face-centered cubic (fcc) and hexagonal closed-packed (hcp) lattices in samples
with particle size less than or equal to 6.0 nm with the prevalence of only fcc
phase beyond this. They are also associated with reduced coordination number,
modified electronic structure, and surface atom coordination with ligands.
Magnetization data furthermore reveal coexistence of ferromagnetism and
superparamagnetism at 300 K. Considered to be due to dominant roles of ligands,
they are likely to open up far-reaching implications to their future
applications.


title:
On complete monotonicity of the Prabhakar function and non-Debye
  relaxation in dielectrics

abstract:
  The three parameters Mittag--Leffler function (often referred as the
Prabhakar function) has important applications, mainly in physics of
dielectrics, in describing anomalous relaxation of non--Debye type. This paper
concerns with the investigation of the conditions, on the characteristic
parameters, under which the function is locally integrable and completely
monotonic; these properties are essential for the physical feasibility of the
corresponding models. In particular the classical Havriliak--Negami model is
extended to a wider range of the parameters. The problem of the numerical
evaluation of the three parameters Mittag--Leffler function is also addressed
and three different approaches are discussed and compared. Numerical
simulations are hence used to validate the theoretical findings and present
some graphs of the function under investigation.

categories: math-ph cond-mat.mtrl-sci math.CV math.MP physics.class-ph


title: Quantum optomechanical straight-twin engine

abstract:
  We propose a realization of a quantum heat engine in a hybrid
microwave-optomechanical system that is the analog of a classical straight-twin
engine. It exploits a pair of polariton modes that operate as out-of-phase
quantum Otto cycles. A third polariton mode that is essential in the coupling
of the optical and microwave fields is maintained in a quasi-dark mode to
suppress disturbances from the mechanical noise. We also find that the
fluctuations in the contributions to the total work from the two polariton
modes are characterized by quantum correlations that generally lead to a
reduction in the extractable work compared to its classical version.


title: The spectral gap of dense random regular graphs

abstract:
  For any $\alpha\in (0,1)$ and any $n^{\alpha}\leq d\leq n/2$, we show that
$\lambda(G)\leq C_\alpha \sqrt{d}$ with probability at least $1-\frac{1}{n}$,
where $G$ is the uniform random $d$-regular graph on $n$ vertices, $\lambda(G)$
denotes its second largest eigenvalue (in absolute value) and $C_\alpha$ is a
constant depending only on $\alpha$. Combined with earlier results in this
direction covering the case of sparse random graphs, this completely settles
the problem of estimating the magnitude of $\lambda(G)$, up to a multiplicative
constant, for all values of $n$ and $d$, confirming a conjecture of Vu. The
result is obtained as a consequence of an estimate for the second largest
singular value of adjacency matrices of random {\it directed} graphs with
predefined degree sequences. As the main technical tool, we prove a
concentration inequality for arbitrary linear forms on the space of matrices,
where the probability measure is induced by the adjacency matrix of a random
directed graph with prescribed degree sequences. The proof is a non-trivial
application of the Freedman inequality for martingales, combined with
boots-trapping and tensorization arguments. Our method bears considerable
differences compared to the approach used by Broder, Frieze, Suen and Upfal
(1999) who established the upper bound for $\lambda(G)$ for $d=o(\sqrt{n})$,
and to the argument of Cook, Goldstein and Johnson (2015) who derived a
concentration inequality for linear forms and estimated $\lambda(G)$ in the
range $d= O(n^{2/3})$ using size-biased couplings.


title: Constrained Maximum Correntropy Adaptive Filtering

abstract:
  Constrained adaptive filtering algorithms inculding constrained least mean
square (CLMS), constrained affine projection (CAP) and constrained recursive
least squares (CRLS) have been extensively studied in many applications. Most
existing constrained adaptive filtering algorithms are developed under mean
square error (MSE) criterion, which is an ideal optimality criterion under
Gaussian noises. This assumption however fails to model the behavior of
non-Gaussian noises found in practice. Motivated by the robustness and
simplicity of maximum correntropy criterion (MCC) in non-Gaussian impulsive
noises, this paper proposes a new adaptive filtering algorithm called
constrained maximum correntropy criterion (CMCC). Specifically, CMCC
incorporates a linear constraint into a MCC filter to solve a constrained
optimization problem explicitly. The proposed adaptive filtering algorithm is
easy to implement and has low computational complexity, and in terms of
convergence accuracy (say lower mean square deviation) and stability, can
significantly outperform those MSE based constrained adaptive algorithms in
presence of heavy-tailed impulsive noises. Additionally, the mean square
convergence behaviors are studied under energy conservation relation, and a
sufficient condition to ensure the mean square convergence and the steady-state
mean square deviation (MSD) of the proposed algorithm are obtained. Simulation
results confirm the theoretical predictions under both Gaussian and non-
Gaussian noises, and demonstrate the excellent performance of the novel
algorithm by comparing it with other conventional methods.


title:
Decay of Activity Complexes, Formation of Unipolar Magnetic Regions and
  Coronal Holes in their Causal Relation

abstract:
  North-south asymmetry of sunspot activity resulted in an asynchronous
reversal of the Sun's polar fields in the current cycle. The asymmetry is also
observed in the formation of polar coronal holes. A stable coronal hole was
first formed at the South Pole, despite the later polar-field reversal there.
The aim of this study is to understand processes making this situation
possible. Synoptic magnetic maps from the Global Oscillation Network Group and
corresponding coronal-hole maps from the Extreme ultraviolet Imaging Telescope
aboard the Solar and Heliospheric Observatory and the Atmospheric Imaging
Assembly aboard the Solar Dynamics Observatory are analyzed here to study a
causal relationship between the decay of activity complexes, evolution of
large-scale magnetic fields, and formation of coronal holes. Ensembles of
coronal holes associated with decaying active regions and activity complexes
are presented. These ensembles take part in global rearrangements of the Sun's
open magnetic flux. In particular, the south polar coronal hole was formed from
an ensemble of coronal holes that originated after the decay of multiple
activity complexes observed during 2014.


title:
Referral-Embedded Provision Point Mechanisms for Crowdfunding of Public
  Projects

abstract:
  Civic Crowdfunding is emerging as a popular means to mobilize funding from
citizens for public projects. A popular mechanism deployed on civic
crowdfunding platforms is a provision point mechanism, wherein, the total
contributions must reach a predetermined threshold in order for the project to
be provisioned (undertaken). Such a mechanism may have multiple equilibria;
unfortunately, in many of these equilibria, the project is not funded even if
it is highly valued among the agents. Recent work has proposed mechanisms with
refund bonuses where the project gets funded in equilibrium if its net value is
higher than a threshold among the agents who are aware of the crowdfunding
effort. In this paper, we formalize the notion of social desirability of a
public project and propose mechanisms which use the idea of referrals to expand
the pool of participants and achieve an equilibrium in which the project gets
funded if its net value exceeds a threshold among the entire agent population.
We call this new class of mechanisms Referral-Embedded Provision Point
Mechanisms (REPPM). We specifically propose two variants of REPPM and both
these mechanisms have the remarkable property that, at equilibrium, referral
bonuses are offered but there is no need for actual payment of these bonuses.
We establish that any given agent's equilibrium strategy is to refer other
agents and to contribute in proportion to the agent's true value for the
project. By referring others to contribute, an agent can, in fact, reduce his
equilibrium contribution. In our view, the proposed mechanisms will lead to an
increase in the number of projects that are funded on civic crowdfunding
platforms.


title:
Validity of Maxwell Equal Area Law for Black Holes Conformally Coupled
  to Scalar Fields in $\text{AdS}_5$ Spacetime

abstract:
  We investigate the $P-V$ criticality and the Maxwell equal area law for a
five-dimensional spherically symmetric AdS black hole with a scalar hair in the
absence of and in the presence of a Maxwell field, respectively. Especially in
the charged case, we give the exact $P-V$ critical values. More importantly, we
analyze the validity and invalidity of the Maxwell equal area law for the AdS
hairy black hole in the scenarios without and with charges, respectively.
Within the scope of validity of the Maxwell equal area law, we point out that
there exists a representative van der Waals-type oscillation in the $P-V$
diagram. This oscillating part that indicates the phase transition from a small
black hole to a large one can be replaced by an isobar. The small and large
black holes share the same Gibbs free energy. We also give the distribution of
the critical points in the parameter space both without and with charges, and
obtain for the uncharged case the fitting formula of the co-existence curve.
Meanwhile, the latent heat is calculated, which gives the energy released or
absorbed between the small and large black hole phases in the
isothermal-isobaric procedure.


title: A Compactness Theorem for Embedded Measured Riemann Surface Laminations

abstract:
  We prove a compactness theorem for embedded measured hyperbolic Riemann
surface laminations in a compact almost complex manifold $(X, J)$. To prove
compactness result, we show that there is a suitable topology on the space of
measured Riemann surface laminations induced by Levy-Prokhorov metric. As an
application of the compactness theorem, we show that given a biholomorphism of
$\phi $ of a closed complex manifold $X$, some power $\phi^k $ ($k>0$) fixes a
measured Riemann surface lamination in $X$.


title:
An infinite linear hierarchy for the incompressible Navier-Stokes
  equation and application

abstract:
  This paper introduces an infinite linear hierarchy for the homogeneous,
incompressible three-dimensional Navier-Stokes equation. The Cauchy problem of
the hierarchy with a factorized divergence-free initial datum is shown to be
equivalent to that of the incompressible Navier-Stokes equation in
$\mathcal{H}^1.$ This allows us to present an explicit formula for solutions to
the incompressible Navier-Stokes equation under consideration. The obtained
formula is an expansion in terms of binary trees encoding the collision
histories of the "particles" in a concise form. Precisely, each term in the
summation of $n$ "particles" collision is expressed by a $n$-parameter singular
integral operator with an explicit kernel in Fourier space, describing a kind
of processes of two-body interaction of $n$ "particles". Therefore, this
formula is a physical expression for the solutions of the incompressible
Navier-Stokes equation.


title: Interlayer Conductance of Graphene with Multiple Transfer Process

abstract:
  Electrical properties of multi-layer graphene are subject to variations due
to random interlayer alignments. In this work we reported graphene interlayer
conductance without special layer aligning. Ohmic contacts between two graphene
layers are observed with resistance variations of more than one order. With
Raman spectroscopy we identify that the lattice angle between twisted graphene
layers is the key variation source. The angular dependence and temperature
dependence of the interlayer conductance suggest that a phonon assistant
tunneling mechanism is valid for the interlayer transport of graphene prepared
by multiple transfer process. We finally derive that the multi-layer graphene
resistance shows an exponential-like distribution due to the random interlayer
misalignments.


title: Constructing Q-Fano 3-folds \`a la Prokhorov & Reid

abstract:
  We generalise a construction by Prokhorov & Reid of two families of Q-Fano
3-folds of index 2 to obtain five more families of Q-Fano 3-folds; four of
index 2 and one of index 3. Two of the families constructed have the same
Hilbert series and we study these cases in more detail.


title: Upwind exciton-polariton propagation in hybrid photonic crystals

abstract:
  In this work we study theoretically the axial spectral asymmetry of a 1D
periodic multilayer systems composed by hybrid two-layers
(isotropic/anisotropic) and for photon energies close to the electronic energy
gaps of semiconductors (excitons). The non-normal optical properties of these
resonant non-magnetic photonic crystals, where linear and quadratic spatial
dispersion effects are both present, will be computed in the framework of
exciton-polariton by self-consistent Maxwell-Schroedinger equation solutions in
the effective mass approximation. The tailoring of hybrid crystal, where
exciton-polariton unidirectional oblique propagation is observed, will be
computed by implementing a simple two-layers minimum model.


title:
Giant Mesoscopic Fluctuations and Long Range Superconducting
  Correlations in Superconductor--Ferromagnet structures

abstract:
  The fluctuating superconducting correlations emerging in dirty hybrid
structures in conditions of the strong proximity effect are demonstrated to
affect the validity range of the widely used formalism of Usadel equations at
mesoscopic scales. In superconductor -- ferromagnet (SF) structures these giant
mesoscopic fluctuations originating from the interference effects for the
Cooper pair wave function in the presence of the exchange field can be
responsible for an anomalously slow decay of superconducting correlations in a
ferromagnet even when the non-collinear and spin-orbit effects are negligible.
The resulting sample-to-sample fluctuations of the Josephson current in SFS
junctions and local density of states in SF hybrid structures can provide an
explanation of the long range proximity phenomena observed in mesoscopic
samples with collinear magnetization.


title:
Improved Performance and Reliability of p-i-n Perovskite Solar Cells via
  Doped Metal Oxides

abstract:
  Perovskite photovoltaics (PVs) have attracted attention because of their
excellent power conversion efficiency (PCE). Critical issues related to large
area PV performance, reliability and lifetime need to be addressed. Here, we
show that doped metal oxides can provide ideal electron selectivity, improved
reliability and stability for perovskite PVs. We report p-i-n perovskite PVs
with device areas ranging from 0.09cm2 to 0.5cm2 incorporating a thick aluminum
doped zinc oxide (AZO) electron selective contact with hysteresis-free PCE of
over 13% and high fill factor values in the range of 80%. AZO provides suitable
energy levels for carrier selectivity, neutralizes the presence of pinholes and
provides intimate interfaces. Devices using AZO exhibit an average PCE increase
of over 20% compared with the devices without AZO and maintain the high PCE for
the larger area devices reported. Furthermore, the device stability of p-i-n
perovskite solar cells under the ISOS-D-1 is enhanced when AZO is used, and
maintains 100% of the initial PCE for over 1000 hours of exposure when AZO/Au
is used as the top electrode. Our results indicate the importance of doped
metal oxides as carrier selective contacts to achieve reliable and high
performance long lived large area perovskite solar cells.


title:
Misestimation of temperature when applying Maxwellian distributions to
  space plasmas described by kappa distributions

abstract:
  This paper presents the misestimation of temperature when observations from a
kappa distributed plasma are analyzed as a Maxwellian. One common method to
calculate the space plasma parameters is by fitting the observed distributions
using known analytical forms. More often, the distribution function is included
in a forward model of the instrument's response, which is used to reproduce the
observed energy spectrograms for a given set of plasma parameters. In both
cases, the modeled plasma distribution fits the measurements to estimate the
plasma parameters. The distribution function is often considered to be
Maxwellian even though in many cases the plasma is better described by a kappa
distribution. In this work we show that if the plasma is described by a kappa
distribution, the derived temperature assuming Maxwell distribution can be
significantly off. More specifically, we derive the plasma temperature by
fitting a Maxwell distribution to pseudo-data produced by a kappa distribution,
and then examine the difference of the derived temperature as a function of the
kappa index. We further consider the concept of using a forward model of a
typical plasma instrument to fit its observations. We find that the relative
error of the derived temperature is highly depended on the kappa index and
occasionally on the instrument's field of view and response.


title:
Towards Microservices and Beyond: An incoming Paradigm Shift in
  Distributed Computing

abstract:
  The microservice architecture is a style inspired by service-oriented
computing that has recently started gaining popularity and that promises to
change the way in which software is perceived, conceived and designed. In this
paper we offer a short overview intended as a collection of bibliographic
references and links in the field of Microservices Science and Engineering
(MSE).


title: $\ell$-adic Poisson Formula and Endoscopy for $p$-Adic Reductive Groups

abstract:
  For two distinguished prime $\ell$ and $p$, we prove a $\ell$-adic version of
the Poisson formula for reductive $p$-adic groups. In order to do this we write
an identity for the trace of regular representation and orbital integrals. Next
we reduce them to orbital integrals for endoscopy groups and look at this as
the special value of $L$-function at $s=0$. And finally show that it is equal
to the special value of motivic $L$-function at $s=0$.


title:
Stacking Spectra in Protoplanetary Disks: Detecting Intensity Profiles
  from Hidden Molecular Lines in HD 163296

abstract:
  We introduce a new stacking method in Keplerian disks that (1) enhances
signal-to-noise ratios (S/N) of detected molecular lines and (2) that makes
visible otherwise undetectable weak lines. Our technique takes advantage of the
Keplerian rotational velocity pattern. It aligns spectra according to their
different centroid velocities at their different positions in a disk and stacks
them. After aligning, the signals are accumulated in a narrower velocity range
as compared to the original line width without alignment. Moreover, originally
correlated noise becomes de-correlated. Stacked and aligned spectra, thus, have
a higher S/N. We apply our method to ALMA archival data of DCN (3-2), DCO+
(3-2), N2D+ (3-2), and H2CO (3_0,3-2_0,2), (3_2,2-2_2,1), and (3_2,1-2_2,0) in
the protoplanetary disk around HD 163296. As a result, (1) the S/N of the
originally detected DCN (3-2), DCO+ (3-2), and H2CO (3_0,3-2_0,2) and N2D+
(3-2) lines are boosted by a factor of >4-5 at their spectral peaks, implying
one order of magnitude shorter integration times to reach the original S/N; and
(2) the previously undetectable spectra of the H2CO (3_2,2-2_2,1) and
(3_2,1-2_2,0) lines are materialized at more than 3 sigma. These dramatically
enhanced S/N allow us to measure intensity distributions in all lines with high
significance. The principle of our method can not only be applied to Keplerian
disks but also to any systems with ordered kinematic patterns.


title: The XXL survey: first results and future

abstract:
  The XXL survey currently covers two 25 sq. deg. patches with XMM observations
of ~10ks. We summarise the scientific results associated with the first release
of the XXL data set, that occurred mid 2016. We review several arguments for
increasing the survey depth to 40 ks during the next decade of XMM operations.
X-ray (z<2) cluster, (z<4) AGN and cosmic background survey science will then
benefit from an extraordinary data reservoir. This, combined with deep
multi-$\lambda$ observations, will lead to solid standalone cosmological
constraints and provide a wealth of information on the formation and evolution
of AGN, clusters and the X-ray background. In particular, it will offer a
unique opportunity to pinpoint the z>1 cluster density. It will eventually
constitute a reference study and an ideal calibration field for the upcoming
eROSITA and Euclid missions.


title:
The Fock-Rosly Poisson Structure as Defined by a Quasi-Triangular
  $r$-Matrix

abstract:
  We reformulate the Poisson structure discovered by Fock and Rosly on moduli
spaces of flat connections over marked surfaces in the framework of Poisson
structures defined by Lie algebra actions and quasitriangular $r$-matrices, and
we show that it is an example of a mixed product Poisson structure associated
to pairs of Poisson actions, which were studied by J.-H. Lu and the author. The
Fock-Rosly Poisson structure corresponds to the quasi-Poisson structure studied
by Massuyeau, Turaev, Li-Bland, and Severa under an equivalence of categories
between Poisson and quasi-Poisson spaces.


title: Statistics of predictions with missing higher order corrections

abstract:
  Effective operators have been used extensively to understand small deviations
from the Standard Model in the search for new physics. So far there has been no
general method to fit for small parameters when higher order corrections in
these parameters are present but unknown. We present a new technique that
solves this problem, allowing for an exact p-value calculation under the
assumption that higher order theoretical contributions can be treated as
gaussian distributed random variables. The method we propose is general, and
may be used in the analysis of any perturbative theoretical prediction,
ie.~truncated power series. We illustrate this new method by performing a fit
of the Standard Model Effective Field Theory parameters, which include
eg.~anomalous gauge and four-fermion couplings.


title: A Survey and Measurement Study of GPU DVFS on Energy Conservation

abstract:
  Energy efficiency has become one of the top design criteria for current
computing systems. The dynamic voltage and frequency scaling (DVFS) has been
widely adopted by laptop computers, servers, and mobile devices to conserve
energy, while the GPU DVFS is still at a certain early age. This paper aims at
exploring the impact of GPU DVFS on the application performance and power
consumption, and furthermore, on energy conservation. We survey the
state-of-the-art GPU DVFS characterizations, and then summarize recent research
works on GPU power and performance models. We also conduct real GPU DVFS
experiments on NVIDIA Fermi and Maxwell GPUs. According to our experimental
results, GPU DVFS has significant potential for energy saving. The effect of
scaling core voltage/frequency and memory voltage/frequency depends on not only
the GPU architectures, but also the characteristic of GPU applications.


title: Non density of stability for holomorphic mappings on P^k

abstract:
  A well-known theorem due to Ma\~n\'e-Sad-Sullivan and Lyubich asserts that
J-stable maps are dense in any holomorphic family of rational maps in dimension
1. In this paper we show that the corresponding result fails in higher
dimension. More precisely, we construct open subsets in the bifurcation locus
in the space of holomorphic mappings of degree d of P^k (C) for every d $\ge$ 2
and k $\ge$ 2.


title:
Discrete $p$-robust $\mathbf{H}(\mathrm{div})$-liftings and a posteriori
  estimates for elliptic problems with $H^{-1}$ source terms

abstract:
  We establish the existence of liftings into discrete subspaces of
$\mathbf{H}(\mathrm{div})$ of piecewise polynomial data on locally refined
simplicial partitions of polygonal/polyhedral domains. Our liftings are robust
with respect to the polynomial degree. This result has important applications
in the a posteriori error analysis of parabolic problems, where it permits the
removal of so-called transition conditions that link two consecutive meshes. It
can also be used in a the posteriori error analysis of elliptic problems, where
it allows the treatment of meshes with arbitrary numbers of hanging nodes
between elements. We present a constructive proof based on the a posteriori
error analysis of an auxiliary elliptic problem with $H^{-1}$ source terms,
thereby yielding results of independent interest. In particular, for such
problems, we obtain guaranteed upper bounds on the error along with
polynomial-degree robust local efficiency of the estimators.


title:
Non-existence of solutions for a mean field equation on flat tori at
  critical parameter $16\pi$

abstract:
  It is known from \cite{LW} that the solvability of the mean field equation
$\Delta u+e^{u}=8n\pi \delta_{0}$ with $n\in\mathbb{N}_{\geq 1}$ on a flat
torus $E_{\tau}$ essentially depends on the geometry of $E_{\tau}$. A
conjecture is the non-existence of solutions for this equation if $E_{\tau}$ is
a rectangular torus, which was proved for $n=1$ in \cite{LW}. For any $n\in
\mathbb{N}_{\geq2}$, this conjecture seems challenging from the viewpoint of
PDE theory. In this paper, we prove this conjecture for $n=2$ (i.e. at critical
parameter $16\pi$).


title:
XMMSL1 J074008.2-853927: a tidal disruption event with thermal and
  non-thermal components

abstract:
  We study X-ray bright tidal disruption events (TDE), close to the peak of
their emission, with the intention of understanding the evolution of their
light curves and spectra. Candidate TDE are identified by searching for soft
X-ray flares from non-active galaxies in recent XMM-Newton slew data. In April
2014, X-ray emission was detected from the galaxy XMMSL1 J074008.2-853927
(a.k.a. 2MASX 07400785-8539307), a factor 20 times higher than an upper limit
from 20 years earlier. Both the X-ray and UV flux subsequently fell, by factors
of 70 and 12 respectively. The bolometric luminosity peaked at Lbol~2E44 ergs/s
with a spectrum that may be modelled with thermal emission in the UV band, a
power-law with slope~2 dominating in the X-ray band above 2 keV and a soft
X-ray excess with an effective temperature of ~86 eV. Rapid variability locates
the X-ray emission to within <73 Rg of the nuclear black hole. Radio emission
of flux density ~1 mJy, peaking at 1.5 GHz was detected 21 months after
discovery. Optical spectra indicate that the galaxy, at a distance of 73 Mpc
(z=0.0173), underwent a starburst 2 Gyr ago and is now quiescent. We consider a
tidal disruption event to be the most likely cause of the flare. If this proves
to be correct then this is a very clean example of a disruption exhibiting both
thermal and non-thermal radiation.


title:
Charge transfer states at the interface of the pentacene monolayer on
  TiO$_2$ and their influence on the optical spectrum

abstract:
  The full monolayer of pentacene adsorbed on rutile TiO$_2$(110) provides an
intriguing model to study charge-transfer excitations where the optically
excited electrons and holes reside on different sides of the internal interface
between the pentacene monolayer and the TiO$_2$ surface. In this work we
investigate the electronic properties of this system with density functional
theory, and compute its excitonic and optical properties making use of \emph{ab
initio} matrix elements. The pentacene molecules are found to lie flat on the
surface, head to tail, and slightly tilted towards the troughs of the oxygen
rows of the surface --- in agreement with experiment. Molecular states appear
in the band gap of the clean TiO$_2$ surface which enable charge transfer
excitations directly from the molecular HOMO to the TiO$_2$ conduction band.
The calculated optical spectrum shows a strong polarization dependence and
displays excitonic resonances corresponding to the charge-transfer states. We
characterize the computed excitons by their symmetry and location in k-space
and use this information to explain the polarization dependence of the optical
spectrum.


title: Predicting encounter and colocation events in metropolitan areas

abstract:
  Despite an extensive literature has been devoted to mine and model mobility
features, forecasting where, when and whom people will encounter/colocate still
deserve further research efforts. Forecasting people's encounter and colocation
features is the key point for the success of many applications ranging from
epidemiology to the design of new networking paradigms and services such as
delay tolerant and opportunistic networks. While many algorithms which rely on
both mobility and social information have been proposed, we propose a novel
encounter and colocation predictive model which predicts user's encounter and
colocation events and their features by exploiting the spatio-temporal
regularity in the history of these events. We adopt weighted features Bayesian
predictor and evaluate its accuracy on two large scales WiFi and cellular
datasets. Results show that our approach could improve prediction accuracy
w.r.t standard naive Bayesian and some of the state-of-the-art predictors.


title:
Circumplanetary disks around young giant planets: a comparison between
  core-accretion and disk instability

abstract:
  Circumplanetary disks can be found around forming giant planets, regardless
of whether core accretion or gravitational instability built the planet. We
carried out state-of-the-art hydrodynamical simulations of the circumplanetary
disks for both formation scenarios, using as similar initial conditions as
possible to unveil possible intrinsic differences in the circumplanetary disk
mass and temperature between the two formation mechanisms. We found that the
circumplanetary disks mass linearly scales with the circumstellar disk mass.
Therefore, in an equally massive protoplanetary disk, the circumplanetary disks
formed in the disk instability model can be only a factor of eight more massive
than their core-accretion counterparts. On the other hand, the bulk
circumplanetary disk temperature differs by more than an order of magnitude
between the two cases. The subdisks around planets formed by gravitational
instability have a characteristic temperature below 100 K, while the core
accretion circumplanetary disks are hot, with temperatures even greater than
1000 K when embedded in massive, optically thick protoplanetary disks. We
explain how this difference can be understood as the natural result of the
different formation mechanisms. We argue that the different temperatures should
persist up to the point when a full-fledged gas giant forms via disk
instability, hence our result provides a convenient criteria for observations
to distinguish between the two main formation scenarios by measuring the bulk
temperature in the planet vicinity.


title: Binary permutation groups: alternating and classical groups

abstract:
  We introduce a new approach to the study of finite binary permutation groups
and, as an application of our method, we prove Cherlin's binary groups
conjecture for groups with socle a finite alternating group, and for the
$\mathcal{C}_1$-primitive actions of the finite classical groups.
  Our new approach involves the notion, defined with respect to a group action,
of a `\emph{beautiful subset}'. We demonstrate how the presence of such subsets
can be used to show that a given action is not binary. In particular, the study
of such sets will lead to a resolution of many of the remaining open cases of
Cherlin's binary groups conjecture.


title: A non-PI minimal system is Li-Yorke sensitive

abstract:
  It is shown that any non-PI minimal system is Li-Yorke sensitive.
Consequently, any minimal system with nontrivial weakly mixing factor (such a
system is non-PI) is Li-Yorke sensitive, which answers affirmatively an open
question by Akin and Kolyada.


title:
Cosmic ray composition measurements and cosmic ray background free
  gamma-ray observations with Cherenkov telescopes

abstract:
  Muon component of extensive air showers (EAS) initiated by cosmic ray
particles carries information on the primary particle identity. We show that
the muon content of EAS could be measured in a broad energy range from 10-100
TeV up to ultra-high-energy cosmic ray range using wide field-of-view imaging
atmospheric Cherenkov telescopes observing strongly inclined or nearly
horizontal EAS from the ground of from high altitude. Cherenkov emission from
muons in such EAS forms a distinct component (halo or tail) of the EAS image in
the telescope camera. We show that detection of the muon signal could be used
to measure composition of the cosmic ray spectrum in the energy ranges of the
knee, the ankle and of the Galactic-to-extragalactic transition. It could also
be used to veto the cosmic ray background in gamma-ray observations. This
technique provides a possibility for up to two orders of magnitude improvement
of sensitivity for gamma-ray flux in the energy band above 10 PeV, compared to
KASCADE-Grande, and an order-of-magnitude improvement of sensitivity in the
multi-EeV energy band, compared to Pierre Auger Observatory.


title:
Multiple Regularizations Deep Learning for Paddy Growth Stages
  Classification from LANDSAT-8

abstract:
  This study uses remote sensing technology that can provide information about
the condition of the earth's surface area, fast, and spatially. The study area
was in Karawang District, lying in the Northern part of West Java-Indonesia. We
address a paddy growth stages classification using LANDSAT 8 image data
obtained from multi-sensor remote sensing image taken in October 2015 to August
2016. This study pursues a fast and accurate classification of paddy growth
stages by employing multiple regularizations learning on some deep learning
methods such as DNN (Deep Neural Networks) and 1-D CNN (1-D Convolutional
Neural Networks). The used regularizations are Fast Dropout, Dropout, and Batch
Normalization. To evaluate the effectiveness, we also compared our method with
other machine learning methods such as (Logistic Regression, SVM, Random
Forest, and XGBoost). The data used are seven bands of LANDSAT-8 spectral data
samples that correspond to paddy growth stages data obtained from i-Sky (eye in
the sky) Innovation system. The growth stages are determined based on paddy
crop phenology profile from time series of LANDSAT-8 images. The classification
results show that MLP using multiple regularization Dropout and Batch
Normalization achieves the highest accuracy for this dataset.


title: On some variational algebraic problems

abstract:
  In this paper by exploiting critical point theory, the existence of two
distinct nontrivial solutions for a nonlinear algebraic system with a parameter
is established. Our goal is achieved by requiring an appropriate behavior of
the nonlinear term $f$ at zero and at infinity. Some applications to difference
equations are also presented.


title:
A Joint Detection-Classification Model for Audio Tagging of Weakly
  Labelled Data

abstract:
  Audio tagging aims to assign one or several tags to an audio clip. Most of
the datasets are weakly labelled, which means only the tags of the clip are
known, without knowing the occurrence time of the tags. The labeling of an
audio clip is often based on the audio events in the clip and no event level
label is provided to the user. Previous works have used the bag of frames model
assume the tags occur all the time, which is not the case in practice. We
propose a joint detection-classification (JDC) model to detect and classify the
audio clip simultaneously. The JDC model has the ability to attend to
informative and ignore uninformative sounds. Then only informative regions are
used for classification. Experimental results on the "CHiME Home" dataset show
that the JDC model reduces the equal error rate (EER) from 19.0% to 16.9%. More
interestingly, the audio event detector is trained successfully without needing
the event level label.


title: Copper adatoms on graphene: theory of orbital and spin-orbital effects

abstract:
  We present a combined DFT and model Hamiltonian analysis of spin-orbit
coupling in graphene induced by copper adatoms in the bridge and top positions,
representing isolated atoms in the dilute limit. The orbital physics in both
systems is found to be surprisingly similar, given the fundamental difference
in the local symmetry. In both systems the Cu p and d contributions at the
Fermi level are very similar. Based on the knowledge of orbital effects we
identify that the main cause of the locally induced spin-orbit couplings are Cu
p and d orbitals. By employing the DFT+U formalism as an analysis tool we find
that both the p and d orbital contributions are equally important to spin-orbit
coupling, although p contributions to the density of states are much higher. We
fit the DFT data with phenomenological tight-binding models developed
separately for the top and bridge positions. Our model Hamiltonians describe
the low-energy electronic band structure in the whole Brillouin zone and allow
us to extract the size of the spin-orbit interaction induced by the local Cu
adatom to be in the tens of meV. By application of the phenomenological models
to Green's function techniques, we find that copper atoms act as resonant
impurities in graphene with large lifetimes of 50 and 100~fs for top and
bridge, respectively.


title: Instabilities in tensorial nonlocal gravity

abstract:
  We discuss the cosmological implications of nonlocal modifications of general
relativity containing tensorial structures. Assuming the presence of standard
radiation- and matter-dominated eras, we show that, except in very particular
cases, the nonlocal terms contribute a rapidly growing energy density. These
models therefore generically do not have a stable cosmological evolution.


title: Congruence lattices forcing nilpotency

abstract:
  Given a lattice $\mathbb{L}$ and a class $K$ of algebraic structures, we say
that $\mathbb{L}$ \emph{forces nilpotency} in $K$ if every algebra $\mathbf{A}
\in K$ whose congruence lattice $\mathrm{Con} (\mathbf{A})$ is isomorphic to
$\mathbb{L}$ is nilpotent. We describe congruence lattices that force
nilpotency, supernilpotency or solvability for some classes of algebras. For
this purpose, we investigate which commutator operations can exist on a given
congruence lattice.


title: Searching Scenes by Abstracting Things

abstract:
  In this paper we propose to represent a scene as an abstraction of 'things'.
We start from 'things' as generated by modern object proposals, and we
investigate their immediately observable properties: position, size, aspect
ratio and color, and those only. Where the recent successes and excitement of
the field lie in object identification, we represent the scene composition
independent of object identities. We make three contributions in this work.
First, we study simple observable properties of 'things', and call it things
syntax. Second, we propose translating the things syntax in linguistic abstract
statements and study their descriptive effect to retrieve scenes. Thirdly, we
propose querying of scenes with abstract block illustrations and study their
effectiveness to discriminate among different types of scenes. The benefit of
abstract statements and block illustrations is that we generate them directly
from the images, without any learning beforehand as in the standard attribute
learning. Surprisingly, we show that even though we use the simplest of
features from 'things' layout and no learning at all, we can still retrieve
scenes reasonably well.


title: Infinity in string cosmology: A review through open problems

abstract:
  We review recent developments in the field of string cosmology with
particular emphasis on open problems having to do mainly with geometric
asymptotics and singularities. We discuss outstanding issues in a variety of
currently popular themes, such as tree-level string cosmology asymptotics,
higher-order string correction effects, M-theory cosmology, braneworlds, and
finally ambient cosmology.


title: Band geometry, Berry curvature and superfluid weight

abstract:
  We present a theory of the superfluid weight in multiband attractive Hubbard
models within the Bardeen-Cooper-Schrieffer (BCS) mean field framework. We show
how to separate the geometric contribution to the superfluid weight from the
conventional one, and that the geometric contribution is associated with the
interband matrix elements of the current operator. Our theory can be applied to
systems with or without time reversal symmetry. In both cases the geometric
superfluid weight can be related to the quantum metric of the corresponding
noninteracting systems. This leads to a lower bound on the superfluid weight
given by the absolute value of the Berry curvature. We apply our theory to the
attractive Kane-Mele-Hubbard and Haldane-Hubbard models, which can be realized
in ultracold atom gases. Quantitative comparisons are made to state of the art
dynamical mean-field theory and exact diagonalization results.


title:
Guaranteed, locally space-time efficient, and polynomial-degree robust a
  posteriori error estimates for high-order discretizations of parabolic
  problems

abstract:
  We consider the a posteriori error analysis of approximations of parabolic
problems based on arbitrarily high-order conforming Galerkin spatial
discretizations and arbitrarily high-order discontinuous Galerkin temporal
discretizations. Using equilibrated flux reconstructions, we present a
posteriori error estimates for a norm composed of the $L^2(H^1)\cap
H^1(H^{-1})$-norm of the error and the temporal jumps of the numerical
solution. The estimators provide guaranteed upper bounds for this norm, without
unknown constants. Furthermore, the efficiency of the estimators with respect
to this norm is local in both space and time, with constants that are robust
with respect to the mesh-size, time-step size, and the spatial and temporal
polynomial degrees. We further show that this norm, which is key for local
space-time efficiency, is globally equivalent to the $L^2(H^1)\cap
H^1(H^{-1})$-norm of the error, with polynomial-degree robust constants. The
proposed estimators also have the practical advantage of allowing for very
general refinement and coarsening between the timesteps.


title: Cancellation for surfaces revisited. I

abstract:
  The celebrated Zariski Cancellation Problem asks as to when the existence of
an isomorphism $X\times\mathbb{A}^n\cong X'\times\mathbb{A}^n$ for (affine)
algebraic varieties $X$ and $X'$ implies that $X\cong X'$. In this paper we
provide a criterion for cancellation by the affine line (that is, $n=1$) in the
case where $X$ is a normal affine surface admitting an $\mathbb{A}^1$-fibration
$X\to B$ over a smooth affine curve $B$. If $X$ does not admit such an
$\mathbb{A}^1$-fibration then the cancellation by the affine line is known to
hold for $X$ by a result of Bandman and Makar-Limanov. It occurs that for a
smooth $\mathbb{A}^1$-fibered affine surface $X$ over $B$ the cancellation by
an affine line holds if and only if $X\to B$ is a line bundle, and, for a
normal such $X$, if and only if $X\to B$ is a cyclic quotient of a line bundle
(an orbifold line bundle). When the cancellation does not hold for $X$ we
include $X$ in a non-isotrivial deformation family $X_\lambda\to B$,
$\lambda\in\Lambda$, of $\mathbb{A}^1$-fibered surfaces with cylinders
$X_\lambda\times\mathbb{A}^1$ isomorphic over $B$. This gives large families of
examples of non-cancellation for surfaces which extend the known examples
constructed by Danielewski, tom Dieck, Wilkens, Masuda and Miyanishi, e.a.


title: A mechanical erosion model for two-phase mass flows

abstract:
  Erosion, entrainment and deposition are complex and dominant, but yet poorly
understood, mechanical processes in geophysical mass flows. Here, we propose a
novel, process-based, two-phase, erosion-deposition model capable of adequately
describing these complex phenomena commonly observed in landslides, avalanches,
debris flows and bedload transport. The model is based on the jump in the
momentum flux including changes of material and flow properties along the
flow-bed interface and enhances an existing general two-phase mass flow model
(Pudasaini, 2012). A two-phase variably saturated erodible basal morphology is
introduced and allows for the evolution of erosion-deposition-depths,
incorporating the inherent physical process including momentum and rheological
changes of the flowing mixture. By rigorous derivation, we show that
appropriate incorporation of the mass and momentum productions or losses in
conservative model formulation is essential for the physically correct and
mathematically consistent description of erosion-entrainment-deposition
processes. We show that mechanically deposition is the reversed process of
erosion. We derive mechanically consistent closures for coefficients emerging
in the erosion rate models. We prove that effectively reduced friction in
erosion is equivalent to the momentum production. With this, we solve the long
standing dilemma of mass mobility, and show that erosion enhances the mass flow
mobility. The novel enhanced real two-phase model reveals some major aspects of
the mechanics associated with erosion, entrainment and deposition. The model
appropriately captures the emergence and propagation of complex frontal surge
dynamics associated with the frontal ambient-drag with erosion.


title: Parallel Large-Scale Attribute Reduction on Cloud Systems

abstract:
  The rapid growth of emerging information technologies and application
patterns in modern society, e.g., Internet, Internet of Things, Cloud Computing
and Tri-network Convergence, has caused the advent of the era of big data. Big
data contains huge values, however, mining knowledge from big data is a
tremendously challenging task because of data uncertainty and inconsistency.
Attribute reduction (also known as feature selection) can not only be used as
an effective preprocessing step, but also exploits the data redundancy to
reduce the uncertainty. However, existing solutions are designed 1) either for
a single machine that means the entire data must fit in the main memory and the
parallelism is limited; 2) or for the Hadoop platform which means that the data
have to be loaded into the distributed memory frequently and therefore become
inefficient. In this paper, we overcome these shortcomings for maximum
efficiency possible, and propose a unified framework for Parallel Large-scale
Attribute Reduction, termed PLAR, for big data analysis. PLAR consists of three
components: 1) Granular Computing (GrC)-based initialization: it converts a
decision table (i.e., original data representation) into a granularity
representation which reduces the amount of space and hence can be easily cached
in the distributed memory: 2) model-parallelism: it simultaneously evaluates
all feature candidates and makes attribute reduction highly parallelizable; 3)
data-parallelism: it computes the significance of an attribute in parallel
using a MapReduce-style manner. We implement PLAR with four representative
heuristic feature selection algorithms on Spark, and evaluate them on various
huge datasets, including UCI and astronomical datasets, finding our method's
advantages beyond existing solutions.


title:
Achieving quantum supremacy with sparse and noisy commuting quantum
  computations

abstract:
  The class of commuting quantum circuits known as IQP (instantaneous quantum
polynomial-time) has been shown to be hard to simulate classically, assuming
certain complexity-theoretic conjectures. Here we study the power of IQP
circuits in the presence of physically motivated constraints. First, we show
that there is a family of sparse IQP circuits that can be implemented on a
square lattice of n qubits in depth O(sqrt(n) log n), and which is likely hard
to simulate classically. Next, we show that, if an arbitrarily small constant
amount of noise is applied to each qubit at the end of any IQP circuit whose
output probability distribution is sufficiently anticoncentrated, there is a
polynomial-time classical algorithm that simulates sampling from the resulting
distribution, up to constant accuracy in total variation distance. However, we
show that purely classical error-correction techniques can be used to design
IQP circuits which remain hard to simulate classically, even in the presence of
arbitrary amounts of noise of this form. These results demonstrate the
challenges faced by experiments designed to demonstrate quantum supremacy over
classical computation, and how these challenges can be overcome.


title:
Diminish Electrostatic in Piezoresponse Force Microscopy through longer
  ultra-stiff tips

abstract:
  Piezoresponse Force Microscopy is a powerful but delicate nanoscale technique
that measures the mechanical response resulting from the application of a
highly localized electric field. Though mechanical response is normally due to
piezoelectricity, other physical phenomena, especially electrostatic
interaction, can contribute to the signal read. We address this problematic
through the use of longer ultra-stiff probes providing state of the art
sensitivity, with the lowest electrostatic interaction and avoiding working in
high frequency regime. In order to find this solution we develop a theoretical
description addressing the effects of electrostatic contributions in the total
cantilever vibration and its quantification for different setups. The theory is
subsequently tested in a Periodically Poled Lithium Niobate (PPLN) crystal, a
sample with well-defined 0deg and 180deg domains, using different commercial
available conductive tips. We employ the theoretical description to compare the
electrostatic contribution effects into the total phase recorded. Through
experimental data our description is corroborated for each of the tested
commercially available probes. We propose that a larger probe length can be a
solution to avoid electrostatic forces, so the cantilever-sample electrostatic
interaction is reduced. For hard oxide samples we propose an ultra-stiff
cantilever which avoids the use of high frequency voltage but still diminishing
electrostatic forces. Our proposed commercially available solution have great
implications into avoiding artifacts while studying soft biological samples,
multiferroic oxides, and thin film ferroelectric materials and it opens a new
window into tip engineering.


title:
Charm quark and meson production in association with single-jet at the
  LHC

abstract:
  We discuss charm quark/antiquark and charmed meson production in association
with one extra jet (gluon, quark, antiquark) at the LHC. The calculations are
performed both in collinear and $k_T$-factorization approaches. Different
unintegrated gluon distribution functions are used in the $k_T$-factorization
approach. Several predictions for the LHC are presented. We show distributions
in rapidity and transverse momenta of $c$/$\bar c$ (or charmed mesons) and the
associated jet as well as some two-dimensional observables. Interesting
correlation effects are predicted, \textit{e.g.} in azimuthal angles
$\varphi_{c\bar{c}}$ and $\varphi_{c\mathrm{\textit{-jet}}}$. We have also
discussed a relation of the $2 \to 2$ and $2 \to 3$ partonic calculations in
the region of large transverse momenta of charm quarks/antiquarks as well as
the similarity of the next-to-leading order collinear approach and the
$k_T$-factorization approach with the KMR unintegrated parton distribution
functions. Integrated cross sections for $D^{0}$ + jet production for ATLAS
detector acceptance and for different cuts on jet transverse momenta are also
presented.


title:
Charge fluctuations and nodeless superconductivity in
  quasi-one-dimensional Ta$_{4}$Pd$_{3}$Te$_{16}$ revealed by $^{125}$Te-NMR
  and $^{181}$Ta-NQR

abstract:
  We report $^{125}$Te nuclear magnetic resonance and $^{181}$Ta nuclear
quadrupole resonance studies on single-crystal Ta$_{4}$Pd$_{3}$Te$_{16}$, which
has a quasi-one-dimensional structure and superconducts below $T_{\rm c}=4.3$
K. $^{181}$Ta with spin $I=7/2$ is sensitive to quadrupole interactions, while
$^{125}$Te with spin $I=1/2$ can only relax by magnetic interactions. By
comparing the spin-lattice relaxation rate ( $1/T_{1}$) of $^{181}$Ta and
$^{125}$Te, we found that electric-field-gradient (EFG) fluctuations develop
below $80$ K. The EFG fluctuations are enhanced with decreasing temperature due
to the fluctuations of a charge density wave that sets in at $T_{\rm CDW}=20$
K, below which the spectra are broadened and $1/T_{1}T$ drops sharply. In the
superconducting state, $1/T_{1}$ shows a Hebel-Slichter coherence peak just
below $T_{\rm c}$ for $^{125}$Te, indicating that Ta$_{4}$Pd$_{3}$Te$_{16}$ is
a full-gap superconductor without nodes in the gap function. The coherence peak
is absent in the $1/T_{1}$ of $^{181}$Ta due to the strong EFG fluctuations.


title:
High-Dimensional Quantum Key Distribution based on Multicore Fiber using
  Silicon Photonic Integrated Circuits

abstract:
  Quantum Key Distribution (QKD) provides an efficient means to exchange
information in an unconditionally secure way. Historically, QKD protocols have
been based on binary signal formats, such as two polarisation states, and the
transmitted information efficiency of the quantum key is intrinsically limited
to 1 bit/photon. Here we propose and experimentally demonstrate, for the first
time, a high-dimensional QKD protocol based on space division multiplexing in
multicore fiber using silicon photonic integrated lightwave circuits. We
successfully realized three mutually unbiased bases in a four-dimensional
Hilbert space, and achieved low and stable quantum bit error rate well below
both coherent attack and individual attack limits. Compared to previous
demonstrations, the use of a multicore fiber in our protocol provides a much
more efficient way to create high-dimensional quantum states, and enables
breaking the information efficiency limit of traditional QKD protocols. In
addition, the silicon photonic circuits used in our work integrate variable
optical attenuators, highly efficient multicore fiber couplers, and
Mach-Zehnder interferometers, enabling manipulating high-dimensional quantum
states in a compact and stable means. Our demonstration pave the way to utilize
state-of-the-art multicore fibers for long distance high-dimensional QKD, and
boost silicon photonics for high information efficiency quantum communications.


title:
Anderson localisation and optical-event horizons in rogue-soliton
  generation

abstract:
  We unveil the relation between the linear Anderson localisation process and
nonlinear modulation instability. Anderson localised modes are formed in
certain temporal intervals due to the random background noise. Such localised
modes seed the formation of solitary waves that will appear during the
modulation instability process at those preferred intervals. Afterwards,
optical-event horizon effects between dispersive waves and solitons produce an
artificial collective acceleration that favours the collision of solitons,
which could eventually lead to a rogue-soliton generation.


title:
Very High-Energy Gamma-Ray Follow-Up Program Using Neutrino Triggers
  from IceCube

abstract:
  We describe and report the status of a neutrino-triggered program in IceCube
that generates real-time alerts for gamma-ray follow-up observations by
atmospheric-Cherenkov telescopes (MAGIC and VERITAS). While IceCube is capable
of monitoring the whole sky continuously, high-energy gamma-ray telescopes have
restricted fields of view and in general are unlikely to be observing a
potential neutrino-flaring source at the time such neutrinos are recorded. The
use of neutrino-triggered alerts thus aims at increasing the availability of
simultaneous multi-messenger data during potential neutrino flaring activity,
which can increase the discovery potential and constrain the phenomenological
interpretation of the high-energy emission of selected source classes (e.g.
blazars). The requirements of a fast and stable online analysis of potential
neutrino signals and its operation are presented, along with first results of
the program operating between 14 March 2012 and 31 December 2015.

categories: hep-ex astro-ph.HE astro-ph.IM physics.ins-det


title:
Entanglement distance between quantum states and its implications for
  density-matrix-renormalization-group study of degenerate ground-states

abstract:
  We study the concept of entanglement distance between two quantum states
which quantifies the amount of information shared between their reduced density
matrices (RDMs). Using analytical arguments combined with
density-matrix-renormalization-group (DMRG) and exact diagonalization (ED)
calculations, we show that for gapless systems the entanglement distance has
power law dependence on the energy separation and subsystem size with
$\alpha_E$ and $\alpha_{\ell}$ exponents, respectively. Using conformal field
theory (CFT) we find $\alpha_E = 2$ and $\alpha_{\ell} = 4$ for Abelian
theories with $c=1$ such as free fermions. For non-Abelian CFTs $\alpha_E = 0$
, and $\alpha_{\ell}$ is twice the conformal dimension of the thermal primary
fields. For instance for $Z_3$ parafermion CFT $\alpha_E = 1$ and
$\alpha_{\ell} = 4/5$. For gapped 1+1D fermion systems, we show that the
entanglement distance divides the low energy excitations into two branches with
different values of $\alpha_E$ and $\alpha_{\ell}$. These two branches are
related to momentum transfers near zero and $\pi$. We also demonstrate that the
entanglement distance reaches its maximum for degenerate states related through
nonlocal operators such as Wilson loops. For example, degenerate ground-states
(GSs) of 2+1 D topological states have maximum entanglement distance. On the
contrary, degenerate GSs related through confined anyon excitations such as
genons have minimum entanglement distance. Various implications of this concept
for quantum simulations are discussed. Finally, based on the ideas developed we
discuss the computational complexity of DMRG algorithms that are capable of
finding all degenerate GSs.


title:
Attosecond Control of Relativistic Electron Bunches using Two-Colour
  Fields

abstract:
  Energy coupling during relativistically intense laser-matter interactions is
encoded in the attosecond motion of strongly driven electrons at the pre-formed
plasma-vacuum boundary. Studying and controlling this motion can reveal details
about the microscopic processes that govern a vast array of light-matter
interaction physics and applications. These include research areas right at the
forefront of extreme laser-plasma science such as laser-driven ion
acceleration1, bright attosecond pulse generation2,3 and efficient energy
coupling for the generation and study of warm dense matter4. Here we
demonstrate attosecond control over the trajectories of relativistic electron
bunches formed during such interactions by studying the emission of extreme
ultraviolet (XUV) harmonic radiation. We describe how the precise addition of a
second laser beam operating at the second harmonic of the driving laser pulse
can significantly transform the interaction by modifying the accelerating
potential provided by the fundamental frequency to drive strong coherent
emission. Numerical particle-in-cell code simulations and experimental
observations demonstrate that this modification is extremely sensitive to the
relative phase of the two beams and can lead to significant enhancements in the
resulting harmonic yield. This work also reveals that the ability to control
these extreme interactions with attosecond precision is an essential
requirement for generation of ultra-bright, high temporal contrast attosecond
radiation for atomic and molecular pump-probe experiments5,6.


title: Remarks on the Lagrangian representation of bi-Hamiltonian equations

abstract:
  The Lagrangian representation of multi-Hamiltonian PDEs has been introduced
by Y. Nutku and one of us (MVP). In this paper we focus on systems which are
(at least) bi-Hamiltonian by a pair $A_1$, $A_2$, where $A_1$ is a
hydrodynamic-type Hamiltonian operator. We prove that finding the Lagrangian
representation is equivalent to finding a generalized vector field $\tau$ such
that $A_2=L_\tau A_1$. We use this result in order to find the Lagrangian
representation when $A_2$ is a homogeneous third-order Hamiltonian operator,
although the method that we use can be applied to any other homogeneous
Hamiltonian operator. As an example we provide the Lagrangian representation of
a WDVV hydrodynamic-type system in $3$ components.


title: An invariant of states on Cuntz algebras

abstract:
  For an arbitrary state $\omega$ on a Cuntz algebra, we define a number $1\leq
\kappa(\omega)\leq \infty$ such that if the GNS representations of $\omega$ and
$\omega'$ are unitarily equivalent, then $\kappa(\omega)=\kappa(\omega')$. By
using $\kappa$, we define minimal states and it is shown that the
classification problem of states is reduced to that of minimal states. By using
results of Dutkay, Haussermann, and Jorgensen, we give a sufficient condition
of the minimality of a state. Properties of $\kappa$ and examples are shown. As
an application, a new invariant of a certain class of endomorphisms of ${\cal
B}({\cal H})$ is given.


title: Spin-torque switching and control using chirped oscillating currents

abstract:
  We propose to use oscillating spin currents with slowly varying frequency
(chirp) to manipulate and control the magnetization dynamics in a nanomagnet.
By recasting the Landau-Lifshitz-Slonczewski equation in a quantum-like
two-level formalism, we show that a chirped spin current polarized in the
direction normal to the anisotropy axis can induce a stable precession of the
magnetic moment at any angle (up to $90^\circ$) with respect to the anisotropy
axis. The drive current can be modest ($10^6\,\rm A/cm^2$ or lower) provided
the chirp rate is sufficiently slow. The induced precession is stable against
thermal noise, even for small nano-objects at room temperature. Complete
reversal of the magnetization can be achieved by adding a small external
magnetic field antiparallel to the easy axis. Alternatively, a combination of
chirped ac and dc currents with different polarization directions can also be
used to trigger the reversal.


title: Electronic ground state of Ni$_2^+$

abstract:
  The $^{4}\Phi_{9/2}$ ground state of the Ni$_2^+$ diatomic molecular cation
is determined experimentally from temperature and magnetic-field-dependent
x-ray magnetic circular dichroism spectroscopy in a cryogenic ion trap, where
an electronic and rotational temperature of $7.4 \pm 0.2$ K was reached by
buffer gas cooling of the molecular ion. The contribution of the magnetic
dipole term to the x-ray magnetic circular dichroism spin sum rule amounts to
$7\, T_z = 0.17 \pm 0.06$ $\mu_B$ per atom, approximately 11 % of the spin
magnetic moment. We find that, in general, homonuclear diatomic molecular
cations of $3d$ transition metals seem to adopt maximum spin magnetic moments
in their electronic ground states.


title:
Modern Dynamical Coupled-Channels Calculations for Extracting and
  Understanding the Nucleon Spectrum

abstract:
  We give an overview of recent progress in the spectroscopic study of nucleon
resonances within the dynamical coupled-channels analysis of meson-production
reactions. The important role of multichannel reaction dynamics in
understanding various properties of nucleon resonances is emphasized.


title: Conductance of closed and open long Aharonov-Bohm-Kondo rings

abstract:
  We calculate the finite temperature linear DC conductance of a generic
single-impurity Anderson model containing an arbitrary number of Fermi liquid
leads, and apply the formalism to closed and open long Aharonov-Bohm-Kondo
(ABK) rings. We show that, as with the short ABK ring, there is a contribution
to the conductance from the connected 4-point Green's function of the
conduction electrons. At sufficiently low temperatures this contribution can be
eliminated, and the conductance can be expressed as a linear function of the
T-matrix of the screening channel. For closed rings we show that at
temperatures high compared to the Kondo temperature, the conductance behaves
differently for temperatures above and below $v_F/L$ where $v_F$ is the Fermi
velocity and $L$ is the circumference of the ring. For open rings, when the
ring arms have both a small transmission and a small reflection, we show from
the microscopic model that the ring behaves like a two-path interferometer, and
that the Kondo temperature is unaffected by details of the ring. Our findings
confirm that ABK rings are potentially useful in the detection of the size of
the Kondo screening cloud, the $\pi/2$ scattering phase shift from the Kondo
singlet, and the suppression of Aharonov-Bohm oscillations due to inelastic
scattering.


title:
Direct observation of charge order in underdoped and optimally doped
  Bi$_{2}$(Sr,La)$_{2}$CuO$_{6+\delta}$ by resonant inelastic x-ray scattering

abstract:
  Charge order in underdoped and optimally doped high-$T_\mathrm{c}$
superconductors Bi$_{2}$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$ (Bi2201) is
investigated by Cu $L_3$ edge resonant inelastic x-ray scattering (RIXS). We
have directly observed charge density modulation in the optimally doped Bi2201
at momentum transfer $Q_{\|} \simeq 0.23$ rlu, with smaller intensity and
correlation length with respect to the underdoped sample. This demonstrates
that short-range charge order in Bi2201 persists up to optimal doping, as in
other hole-doped cuprates. We explored the nodal (diagonal) direction and found
no charge order peak, confirming that charge order modulates only along the
Cu-O bond directions. We measured the out-of-plane dependence of charge order,
finding a flat response and no maxima at half integer \emph{L} values. This
suggests there is no out-of-plane phase correlation in single layer Bi2201, at
variance from YBa$_2$Cu$_3$O$_{6+x}$ and La$_{2-x}$(Ba,Sr)$_x$CuO$_4$.
Combining our results with data from the literature we assess that charge order
in Bi2201 exists in a large doping range across the phase diagram, i.e. $0.07
\lesssim p \lesssim 0.16$, demonstrating thereby that it is intimately
entangled with the antiferromagnetic background, the pseudogap and
superconductivity.


title: Spectral Asymptotics for Magnetic Schroedinger Operator

abstract:
  In this article we obtain eigenvalue asymptotics for 2D and 3D-Schroedinger,
Schroedinger-Pauli and Dirac operators in the situations in which the role of
the magnetic field is important. These operators are essentially different and
there is a significant difference between 2D and 3D-operators.


title: $K$-theory of monoid algebras and a question of Gubeladze

abstract:
  We show that for any commutative noetherian regular ring $R$ containing $\Q$,
the map $K_1(R) \to K_1(\frac{R[x_1, \cdots , x_4]}{(x_1x_2 - x_3x_4)})$ is an
isomorphism. This answers a question of Gubeladze. We also compute the higher
$K$-theory of this monoid algebra. In particular, we show that the above
isomorphism does not extend to all higher $K$-groups. We give applications to a
question of Lindel on the Serre dimension of monoid algebras.


title: Phenomenological Implications of Very Special Relativity

abstract:
  We discuss several phenomenological implications of Very Special Relativity
(VSR). It is assumed that there is a small violation of Lorentz invariance and
the true symmetry group of nature is a subgroup called SIM(2). This symmetry
group postulates the existence of a fundamental or preferred direction in
space-time. We study its implications by using an effective action which
violates Lorentz invariance but respects VSR. We find that the problem of
finding the masses of fundamental fermions is in general intractable in the
presence of VSR term. The problem can be solved only in special cases which we
pursue in this paper. We next determine the signal of VSR in torsion pendulum
experiment as well as clock comparison experiment. We find that VSR predicts a
signal which is different from other Lorentz violating theories and hence a
dedicated data analysis is needed in order to impose reliable limits. Assuming
that signal is absent in data we determine the limits that can be imposed on
the VSR parameters. We also study the implications of VSR in particle decay
experiments taking the charged pion and kaon decay as an example. The effective
interaction between the charged pion and the final state leptons is related to
the fundamental VSR mass terms through a loop calculation. We also predict a
shift in the angular dependence of the decay products due to VSR. In particular
we find that these no longer display azimuthal symmetry with respect to the
momentum of the pion. Furthermore the azimuthal and polar angle distributions
show time dependence with a period of a sidereal day. This time dependence
provides us with a novel method to test VSR in future experiments.


title: Cosmology with bulk viscosity and the gravitino problem

abstract:
  The gravitino problem is revisited in the framework of cosmological models in
which the primordial cosmic matter is described by a relativistic imperfect
fluid. Dissipative effects (or bulk viscosity effects) arise owing to the
different cooling rates of the fluid components. We show that the effects of
the bulk viscosity allow to avoid the late abundance of gravitinos. In
particular, we found that for a particular choice of the parameters
characterizing the cosmological model, the gravitino abundance turns out to be
independent on the reheating temperature.


title: A law of the iterated logarithm for directed last passage percolation

abstract:
  A law of the iterated logarithm is established for the last passage times of
directed percolation on rectangles in the plane over exponential or geometric
independent random variables, rescaled to converge to the Tracy-Widom
distribution. The normalization is of loglog type, in contrast with the log
normalization for the largest eigenvalue of a GUE matrix recently put forward
by E. Paquette and O. Zeitouni. The proof relies on sharp tail bounds and
superadditivity, close to the standard law of the iterated logarithm. A weaker
result for the liminf is also discussed.


title:
Quantum and Information Thermodynamics: A Unifying Framework based on
  Repeated Interactions

abstract:
  We expand the standard thermodynamic framework of a system coupled to a
thermal reservoir by considering a stream of independently prepared units
repeatedly put into contact with the system. These units can be in any
nonequilibrium state and interact with the system with an arbitrary strength
and duration. We show that this stream constitutes an effective resource of
nonequilibrium free energy and identify the conditions under which it behaves
as a heat, work or information reservoir. We also show that this setup provides
a natural framework to analyze information erasure ("Landauer's principle") and
feedback controlled systems ("Maxwell's demon"). In the limit of a short
system-unit interaction time, we further demonstrate that this setup can be
used to provide a thermodynamically sound interpretation to many effective
master equations. We discuss how non-autonomously driven systems, micromasers,
lasing without inversion, and the electronic Maxwell demon, can be
thermodynamically analyzed within our framework. While the present framework
accounts for quantum features (e.g. squeezing, entanglement, coherence), we
also show that quantum resources do not offer any advantage compared to
classical ones in terms of the maximum extractable work.


title: Semi-equivelar and vertex-transitive maps on the torus

abstract:
  A vertex-transitive map $X$ is a map on a closed surface on which the
automorphism group ${\rm Aut}(X)$ acts transitively on the set of vertices. If
the face-cycles at all the vertices in a map are of same type then the map is
said to be a semi-equivelar map. Clearly, a vertex-transitive map is
semi-equivelar. Converse of this is not true in general. We show that there are
eleven types of semi-equivelar maps on the torus. Three of these are equivelar
maps. It is known that two of the three types of equivelar maps on the torus
are always vertex-transitive. We show that this is true for the remaining one
type of equivelar map and one other type of semi-equivelar maps, namely, if $X$
is a semi-equivelar map of type $[6^3]$ or $[3^3, 4^2]$ then $X$ is
vertex-transitive. We also show, by presenting examples, that this result is
not true for the remaining seven types of semi-equivelar maps. There are ten
types of semi-equivelar maps on the Klein bottle. We present examples in each
of the ten types which are not vertex-transitive.


title: Trapping of Atoms by the Counter-Propagating Stochastic Light Waves

abstract:
  We calculate the temperature of the atoms in the field of counter-propagating
stochastic light waves (the chaotic-field model). We show that the temperature
of the atomic ensemble depends on the autocorrelation time of the waves, their
intensity and the detuning of the carrier frequency of the waves from the
atomic transition frequency. The field can form a one-dimensional trap for
atoms, as is readily seen from our previous investigation of light-pressure
force on an atom in counter-propagating stochastic light waves [V. I.
Romanenko, B. W. Shore, L. P. Yatsenko, Opt. Commun. 268 (2006) 121-132]. We
carry out a numerical simulation of the atomic ensemble using parameters
appropriate for sodium atoms. Analyzing the known investigation of the
light-pressure force on atoms and their motion in the counter-propagating
polychromatic waves, we suggest an hypothesis that any polychromatic
counter-propagating waves that have a discrete spectrum, or waves described by
a stationary stochastic process, one of which repeats the other, can form a
trap for atoms.


title: Epiphany-V: A 1024 processor 64-bit RISC System-On-Chip

abstract:
  This paper describes the design of a 1024-core processor chip in 16nm FinFet
technology. The chip ("Epiphany-V") contains an array of 1024 64-bit RISC
processors, 64MB of on-chip SRAM, three 136-bit wide mesh Networks-On-Chip, and
1024 programmable IO pins. The chip has taped out and is being manufactured by
TSMC.
  This research was developed with funding from the Defense Advanced Research
Projects Agency (DARPA). The views, opinions and/or findings expressed are
those of the author and should not be interpreted as representing the official
views or policies of the Department of Defense or the U.S. Government.


title:
On the inequivalence of the CH and CHSH inequalities due to finite
  statistics

abstract:
  Different variants of a Bell inequality, such as CHSH and CH, are known to be
equivalent when evaluated on nonsignaling outcome probability distributions.
However, in experimental setups, the outcome probability distributions are
estimated using a finite number of samples. Therefore the nonsignaling
conditions are only approximately satisfied and the robustness of the violation
depends on the chosen inequality variant. We explain that phenomenon using the
decomposition of the space of outcome probability distributions under the
action of the symmetry group of the scenario, and propose a method to optimize
the statistical robustness of a Bell inequality. In the process, we describe
the finite group composed of relabeling of parties, measurement settings and
outcomes, and identify correspondences between the irreducible representations
of this group and properties of outcome probability distributions such as
normalization, signaling or having uniform marginals.


title: A spectroscopic study of the Globular Cluster M28 (NGC~6626)

abstract:
  We present the abundance analysis for a sample of 17 red giant branch stars
in the metal-poor globular cluster M28 based on high resolution spectra. This
is the first extensive spectroscopic study of this cluster. We derive
abundances of O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr,
Ba, La, Ce, and Eu. We find a metallicity of [Fe/H]=-1.29+-0.01 and an
alpha-enhancement of +0.34+-0.01 (errors on the mean), typical of Halo Globular
Clusters in this metallicity regime. A large spread is observed in the
abundances of light elements O, Na, and Al. Mg also shows an anticorrelation
with Al with a significance of 3 sigma. The cluster shows a Na-O
anticorrelation and a Na-Al correlation. This correlation is not linear but
"segmented" and that the stars are not distributed continuously, but form at
least 3 well separated sub-populations. In this aspect M28 resembles NGC~2808
that was found to host at least 5 sub-populations. The presence of a Mg-Al
anticorrelation favor massive AGB stars as the main polluters responsible for
the multiple-population phenomenon.