title: On energy-momentum and spin/helicity of quark and gluon fields

abstract:
  In special relativity, quantum matter can be classified according to
mass-energy and spin. The corresponding field-theoretical notions are the
energy-momentum-stress tensor T and the spin angular momentum tensor S. Since
each object in physics carries energy and, if fermionic, also spin, the notions
of T and S can be spotted in all domains of physics. We discuss the T and S
currents in Special Relativity (SR), in General Relativity (GR), and in the
Einstein-Cartan theory of gravity (EC). We collect our results in 4 theses: (i)
The quark energy-momentum and the quark spin are described correctly by the
canonical (Noether) currents T and S, respectively. (ii) The gluon
energy-momentum current is described correctly by the (symmetric and gauge
invariant) Minkowski type current. Its (Lorentz) spin current vanishes, S = 0.
However, it carries helicity of plus or minus one. (iii) GR contradicts thesis
(i), but is compatible with thesis (ii). (iv) Within the viable EC-theory, our
theses (i) and (ii) are fulfilled and, thus, we favor this gravitational
theory.


title: How a Blister Heals

abstract:
  We use experiments to study the dynamics of the healing of a blister, a
localized bump in a thin elastic layer that is adhered to a soft substrate
everywhere except at the bump. We create a blister by gently placing a glass
cover slip on a PDMS substrate. The pressure jump across the elastic layer
drives fluid flow through micro-channels that form at the interface between the
layer and the substrate; these channels coalesce at discrete locations as the
blister heals and eventually disappear at a lower critical radius. The spacing
of the channel follows a simple scaling law that can be theoretically
justified, and the kinetics of healing is rate limited by fluid flow, but with
a non-trivial dependence on the substrate thickness that likely arises due to
channelization. Our study is relevant to a variety of soft adhesion scenarios.


title:
Absorption of Light by Excitons and Trions in Monolayers of Metal
  Dichalcogenide MoS$_{2}$: Experiments and Theory

abstract:
  We measure the optical absorption spectra and optical conductivities of
excitons and trions in monolayers of metal dichalcogenide MoS$_{2}$ and compare
the results with theoretical models. Our results show that the Wannier-Mott
model for excitons, with modifications to account for small exciton radii and
large exciton relative wavefunction spread in momentum space, phase space
blocking due to Pauli exclusion in doped materials, and wavevector dependent
dielectric constant, gives results that agree well with experiments. The
measured exciton optical absorption spectra are used to obtain experimental
estimates for the exciton radii that fall in the $7-10\AA$ range and agree well
with theory. The measured trion optical absorption spectra are used to obtain
values for the trion radii that also agree well with theory. The measured
values of the exciton and trion radii correspond to binding energies that are
in good agreement with values obtained from first principles calculations.


title:
A Many-core Machine Model for Designing Algorithms with Minimum
  Parallelism Overheads

abstract:
  We present a model of multithreaded computation, combining fork-join and
single-instruction-multiple-data parallelisms, with an emphasis on estimating
parallelism overheads of programs written for modern many-core architectures.
We establish a Graham-Brent theorem for this model so as to estimate execution
time of programs running on a given number of streaming multiprocessors. We
evaluate the benefits of our model with four fundamental algorithms from
scientific computing. In each case, our model is used to minimize parallelism
overheads by determining an appropriate value range for a given program
parameter; moreover experimentation confirms the model's prediction.


title: Existence of Magnetic Compressible Fluid Stars

abstract:
  The existence of magnetic star solutions which are axi-symmetric stationary
solutions for the Euler-Poisson system of compressible fluids coupled to a
magnetic field is proved in this paper by a variational method. Our method of
proof consists of deriving an elliptic equation for the magnetic potential in
cylindrical coordinates in $\mathbb{R}^3$, and obtaining the estimates of the
Green's function for this elliptic equation by transforming it to 5-Laplacian.


title:
A stochastic domain decomposition method for time dependent mesh
  generation

abstract:
  We use a time-relaxed linear grid generator of Winslow type to propose a new
deterministic-stochastic domain decomposition approach to the generation of
adaptive moving meshes. The method uses the probabilistic form of the exact
solution of the linear mesh generator to provide the sub-domain interface
values that serve as boundary conditions for the domain decomposition. The
meshes over the single sub-domains can then be obtained independently of each
other in an entirely parallel fashion. We demonstrate numerically the
capability of the method to yield smooth, time-evolving meshes.


title:
Improved Accuracy of Incompressible Approximation of Compressible Euler
  Equations

abstract:
  This article addresses a fundamental concern regarding the incompressible
approximation of fluid motions, one of the most widely used approximations in
fluid mechanics. Common belief is that its accuracy is $O(\epsilon)$ where
$\epsilon$ denotes the Mach number. In this article, however, we prove an
$O(\epsilon^2)$ accuracy for the incompressible approximation of the
isentropic, compressible Euler equations thanks to several decoupling
properties. At the initial time, the velocity field and its first time
derivative are of $O(1)$ size, but the boundary conditions can be as stringent
as the solid-wall type. The fast acoustic waves are still $O(\epsilon)$ in
magnitude, since the $O(\epsilon^2)$ error is measured in the sense of Leray
projection and more physically, in time-averages. We also show when a passive
scalar is transported by the flow, it is $O(\epsilon^2)$ accurate {\it
pointwise in time} to use incompressible approximation for the velocity field
in the transport equation.


title: A Galactic Origin for the Fast Radio Burst FRB010621

abstract:
  The recent detection of Fast Radio Bursts (FRBs) has generated strong
interest in identifying the origin of these bright, non-repeating, highly
dispersed pulses. The principal limitation in understanding the origin of these
bursts is the lack of reliable distance estimates; their high dispersion
measures imply that they may be at cosmological distances ($0.1 < z < 1.0$).
Here we discuss new distance constraints to the FRB010621 (a.k.a J1852$-$08)
first reported by Keane. We use velocity resolved $H\alpha$ and $H\beta$
observations of diffuse ionised gas toward the burst to calculate an
extinction-corrected emission measure along the line of sight. We combine this
emission measure with models of Galactic rotation and of electron distribution
to derive a 90% probability of the pulse residing in the Galaxy. However, we
cannot differentiate between the two Galactic interpretations of Keane: a
neutron star with unusual pulse amplitude distribution or Galactic black hole
annihilation.


title: Dimensional crossover in layered $f$-electron superlattices

abstract:
  Motivated by the remarkable experimental realizations of $f$-electron
superlattices, e.g. CeIn$_3$/LaIn$_3$- and CeCoIn$_5$/YbCoIn$_5$-
superlattices, we analyze the formation of heavy electrons in layered
$f$-electron superlattices by means of the dynamical mean field theory. We show
that the spectral function exhibits formation of heavy electrons in the entire
system below a temperature scale $T_0$. However, in terms of transport, two
different coherence temperatures $T_x$ and $T_z$ are identified in the
in-plane- and the out-of-plane-resistivity, respectively. Remarkably, we find
$T_z < T_x \sim T_0$ due to scatterings between different reduced Brillouin
zones. The existence of these two distinct energy scales implies a crossover in
the dimensionality of the heavy electrons between two and three dimensions as
temperature or layer geometry is tuned. This dimensional crossover would be
responsible for the characteristic behaviors in the magnetic and
superconducting properties observed in the experiments.


title:
Rediscovering Black Phosphorus: A Unique Anisotropic 2D Material for
  Optoelectronics and Electronics

abstract:
  Anisotropy refers to the property of a material exhibiting directionally
dependent features. In this paper, we introduce black phosphorous (BP), the
most stable allotrope of phosphorus in layered orthorhombic structure with a
bandgap of 0.3 eV in bulk, as a unique 2D material in which electrons, phonons
and their interactions with photons behave in a highly anisotropic manner
within the plane of the layers. The unique anisotropic nature of BP thin films
is revealed using angle-resolved Raman and infrared spectroscopies, together
with angle-resolved transport study. For 15 nm thick BP, we measure Hall
mobility of 1000 and 600 cm^2/Vs for holes along the light (x) and heavy (y)
effective mass directions, respectively, at 120 K. These BP thin films also
exhibit large and anisotropic in-plane optical conductivity from 2 to 5
micrometer wavelength. Field effect transistors using 4 to 30 layers of BP (2
to 15 nm) as channel material exhibit an on-off current ratio exceeding 10^5, a
field-effect mobility of 205 cm^2/Vs, and good saturation properties all at
room temperature, suggesting its promising future in high performance thin film
electronics. By introducing narrow bandgap BP into the 2D material family, we
fill the space between semi-metallic graphene and large bandgap TMDCs, where
great potentials for infrared optoelectronics lie. Most importantly, the unique
anisotropic nature of this intriguing material creates unprecedented
possibilities for the realization of conceptually new optoelectronic and
electronic devices in which angle-dependent physical properties are highly
desirable.


title:
A Generalized Nonlocal Calculus with Application to the Peridynamics
  Model for Solid Mechanics

abstract:
  A nonlocal vector calculus was introduced in [2] that has proved useful for
the analysis of the peridynamics model of nonlocal mechanics and nonlocal
diffusion models. A generalization is developed that provides a more general
setting for the nonlocal vector calculus that is independent of particular
nonlocal models. It is shown that general nonlocal calculus operators are
integral operators with specific integral kernels. General nonlocal calculus
properties are developed, including nonlocal integration by parts formula and
Green's identities. The nonlocal vector calculus introduced in [2] is shown to
be recoverable from the general formulation as a special example. This special
nonlocal vector calculus is used to reformulate the peridynamics equation of
motion in terms of the nonlocal gradient operator and its adjoint. A new
example of nonlocal vector calculus operators is introduced, which shows the
potential use of the general formulation for general nonlocal models.


title: Forcing a sparse minor

abstract:
  This paper addresses the following question for a given graph $H$: what is
the minimum number $f(H)$ such that every graph with average degree at least
$f(H)$ contains $H$ as a minor? Due to connections with Hadwiger's Conjecture,
this question has been studied in depth when $H$ is a complete graph. Kostochka
and Thomason independently proved that $f(K_t)=ct\sqrt{\ln t}$. More generally,
Myers and Thomason determined $f(H)$ when $H$ has a super-linear number of
edges. We focus on the case when $H$ has a linear number of edges. Our main
result, which complements the result of Myers and Thomason, states that if $H$
has $t$ vertices and average degree $d$ at least some absolute constant, then
$f(H)\leq 3.895\sqrt{\ln d}\,t$. Furthermore, motivated by the case when $H$
has small average degree, we prove that if $H$ has $t$ vertices and $q$ edges,
then $f(H) \leq t+6.291q$ (where the coefficient of 1 in the $t$ term is best
possible).


title:
The Designing of Online Multiple Intelligence Tools for Lecturers at
  Polytechnic

abstract:
  This paper addresses the designing of Online Multiple Intelligence (MI)
Teaching Tools for Polytechnic lecturers. These teaching tools can assist
lecturers to create their own teaching materials without having any knowledge
of Information Technology (IT) especially in programming. The theory of MI is
used in this paper and this theory postulates that everybody has at least two
or more intelligences. Multiple approaches embedded into a series of activities
via online teaching tools must be implemented in order to achieve effective
teaching and learning in the classroom. The objectives of this paper are to
identify the relationship between the students self-perceived MI and their
academic achievement in Polytechnic, and design online MI tools for teaching at
Polytechnic. This paper also addressed the theoretical framework and MI
teaching activities. The instrument used for this study was Ujian Multiple
Intelligence (UMI). The results showed Polytechnic students have strength in
Interpersonal, Visual-Spatial and Verbal-Linguistic intelligences.


title: What bipartite states are lazy

abstract:
  A bipartite state is called lazy if the entropy rate of one subsystem is
vanishing for any coupling to the other subsystem. In this paper, we provide a
necessary and sufficient condition for a finite-dimensional bipartite state to
be lazy, and prove that a two-mode Gaussian state is lazy if and only if it is
a direct product state.


title:
Aging as a mean to retain an adaptive mutation rate in mutagenesis with
  asymmetric reproduction

abstract:
  The paper discusses a connection between asymmetric reproduction -- that is
reproduction in a parent-child relationship where the parent does not mutate
during reproduction --, the fact that all non-viral lifeforms bear genes of
their reproduction machinery and how this could relate to evolutionary
mechanisms behind aging. In a highly simplified model of the evolution process
rules are derived under which aging is an important factor of the adaption in
the evolution process and what groups of life-forms necessarily have to age and
where exceptions from that rule are possible.


title: KMS states on the C*-algebras of reducible graphs

abstract:
  We consider the dynamics on the C*-algebras of finite graphs obtained by
lifting the gauge action to an action of the real line. Enomoto, Fujii and
Watatani proved that if the vertex matrix of the graph is irreducible, then the
dynamics on the graph algebra admits a single KMS state. We have previously
studied the dynamics on the Toeplitz algebra, and explicitly described a
finite-dimensional simplex of KMS states for inverse temperatures above a
critical value. Here we study the KMS states for graphs with reducible vertex
matrix, and for inverse temperatures at and below the critical value. We prove
a general result which describes all the KMS states at a fixed inverse
temperature, and then apply this theorem to a variety of examples. We find that
there can be many patterns of phase transition, depending on the behaviour of
paths in the underlying graph.


title:
On convergence of entropy of distribution functions in the max domain of
  attraction of max stable laws

abstract:
  Max stable laws are limit laws of linearly normalized partial maxima of
indepen- dent, identically distributed (iid) random variables (rvs). These are
analogous to stable laws which are limit laws of normalized partial sums of iid
rvs. In this paper, we study entropy limit theorems for distribution functions
in the max domain of attraction of max stable laws under linear normalization.
More specifically, we study the problem of convergence of the Shannon entropy
of linearly normalized partial maxima of iid rvs to the corresponding limit
entropy when the linearly normalized partial maxima converges to some
nondegenerate rv. We are able to show that the Shannon entropy not only
converges but, in fact, increases to the limit entropy in some cases. We
discuss several examples. We also study analogous results for the k-th upper
extremes.


title:
Magnetism and Magnetic Anisotropy of Transition Metal-Phthalocyanine
  Molecules

abstract:
  Search for single-molecule magnets (SMMs) with high blocking temperature (TB)
is urgent for practical applications in magnetic recording, molecular
spintronics and quantum computing. Based on the First-principles calculations,
magnetic anisotropy energies (MAE) of the transition metal-Phthalocyanine
(TM-Pc) molecules are investigated and the mechanism that determines the MAE of
TM-Pc molecules is established. In particular, colossal MAE > 100 meV can be
obtained by adding an Os atom on RuPc and OsPc, so these molecules may offer
ultrahigh thermal stability in devices.


title:
Light Focusing and Two-Dimensional Imaging Through Scattering Media
  using the Photoacoustic Transmission-Matrix with an Ultrasound Array

abstract:
  We implement the photoacoustic transmission-matrix approach on a
two-dimensional photoacoustic imaging system, using a 15 MHz linear ultrasound
array. Using a black leaf skeleton as a complex absorbing structure, we
demonstrate that the photoacoustic transmission-matrix approach allows to
reveal structural features that are invisible in conventional photoacoustic
images, as well as to selectively control light focusing on absorbing targets,
leading to a local enhancement of the photoacoustic signal.


title:
Topological rigidity and actions on contractible manifolds with discrete
  singular set

abstract:
  The problem of equivariant rigidity is the $\Gamma$-homeomorphism
classification of $\Gamma$-actions on manifolds with compact quotient and with
contractible fixed sets for all finite subgroups of $\Gamma$. In other words,
this is the classification of cocompact $E_{fin}\Gamma$-manifolds.
  We use surgery theory, algebraic $K$-theory, and the Farrell--Jones
Conjecture to give this classification for a family of groups which satisfy the
property that the normalizers of nontrivial finite subgroups are themselves
finite. More generally, we study cocompact proper actions of these groups on
contractible manifolds and prove that the $E_{fin}$-condition is always
satisfied.


title:
Long-range correlations in proton-nucleus collisions in MC model with
  string fusion

abstract:
  The study of long-range correlations between observables in two rapidity
windows was proposed as a signature of the string fusion and percolation
phenomenon. In the present work we calculate the correlation functions and
coefficients for p-Pb collisions in the framework of the Monte Carlo
string-parton model, based on the picture of elementary collisions of color
dipoles. It describes pA and AA scattering without referring to the Glauber
picture of independent nucleons collisions and includes effects of string
fusion. Different types of correlations are considered: n-n, pt-n, pt-pt, where
n is the event multiplicity of charged particles in a given rapidity window and
pt is their mean transverse momentum. The results, obtained in the present work
for p-Pb collisions, are compared with available experimental results for pt-n
correlations in one window and further predictions are made.


title:
Principled Graph Matching Algorithms for Integrating Multiple Data
  Sources

abstract:
  This paper explores combinatorial optimization for problems of max-weight
graph matching on multi-partite graphs, which arise in integrating multiple
data sources. Entity resolution-the data integration problem of performing
noisy joins on structured data-typically proceeds by first hashing each record
into zero or more blocks, scoring pairs of records that are co-blocked for
similarity, and then matching pairs of sufficient similarity. In the most
common case of matching two sources, it is often desirable for the final
matching to be one-to-one (a record may be matched with at most one other);
members of the database and statistical record linkage communities accomplish
such matchings in the final stage by weighted bipartite graph matching on
similarity scores. Such matchings are intuitively appealing: they leverage a
natural global property of many real-world entity stores-that of being nearly
deduped-and are known to provide significant improvements to precision and
recall. Unfortunately unlike the bipartite case, exact max-weight matching on
multi-partite graphs is known to be NP-hard. Our two-fold algorithmic
contributions approximate multi-partite max-weight matching: our first
algorithm borrows optimization techniques common to Bayesian probabilistic
inference; our second is a greedy approximation algorithm. In addition to a
theoretical guarantee on the latter, we present comparisons on a real-world ER
problem from Bing significantly larger than typically found in the literature,
publication data, and on a series of synthetic problems. Our results quantify
significant improvements due to exploiting multiple sources, which are made
possible by global one-to-one constraints linking otherwise independent
matching sub-problems. We also discover that our algorithms are complementary:
one being much more robust under noise, and the other being simple to implement
and very fast to run.


title:
Multi-Regulator Functional Renormalization Group for Many-Fermion
  Systems

abstract:
  We propose a method of multi-regulator functional renormalization group
(MR-FRG) which is a novel formulation of functional renormalization group with
multiple infrared regulators. It is applied to a two-component fermionic system
with an attractive contact interaction to study crossover phenomena between the
Bardeen-Cooper-Schrieffer (BCS) phase and the Bose-Einstein condensation (BEC)
phase. To control both the fermionic one-particle excitations and the bosonic
collective excitations,IR regulators are introduced, one for the fermionic
two-point function and another for the four-fermion vertex. It is shown that
the Nozi\`eres-Schmitt-Rink (NSR) theory, which is successful to capture
qualitative features of the BCS-BEC crossover, can be derived from MR-FRG. Some
aspects of MR-FRG to go beyond the NSR theory are also discussed.

categories: cond-mat.quant-gas cond-mat.supr-con hep-ph nucl-th


title:
Superfluid, Supersolid and Checkerboard Solid in Two-Component Bosons in
  an Optical Lattice: Study by Means of Gross-Pitaevskii Theory and Monte-Carlo
  Simulations

abstract:
  The bosonic t-J model is a strong-on-site repulsion limit of the
two-component Bose-Hubbard model and is expected to be realized by experiments
of cold atoms in an optical lattice. In previous papers, we studied the bosonic
t-J model by both analytical methods and numerical Monte - Carlo (MC)
simulations. However, in the case of finite $J_z$, where $J_z$ is the
$z$-component coupling constant of the pseudospin interaction, the phase
diagram of the model was investigated by assuming the checkerboard type of
boson densities. In this study, we shall continue our previous study of the
bosonic t-J model using both the Gross-Pitaevskii (GP) theory and MC
simulations without assuming any pattern of boson densities. These two methods
complement each other and give reliable results. We show that as $J_z$ is
increased, the superfluid state evolves into a supersolid (SS), and furthermore
into a genuine solid with the checkerboard symmetry. In the present study, we
propose a method identifying quantum phase transitions in the GP theory. We
also study finite-temperature phase transitions of the superfluidity and the
diagonal solid order of the SS by MC simulations.


title:
Development of Multilayer Readout Wiring TES Calorimeter for Future
  X-ray Missions

abstract:
  We have fabricated multilayer readout wiring Transition Edge Sensors (TES),
which enable us to realize both large effective area and high-energy resolution
for future X-ray astrophysical missions, such as DIOS. By sandwiching a SiO2
insulation layer between Al superconducting signal and return lines,
self/mutual inductances and self fielding of bias leads are expected to be
reduced. We fabricated 4x4 and 20x20 TES array on the multilayer wiring and
tested their performance. Under the low temperature condition, several pixels
in the TES array showed sharp superconducting transitions at around ~300 mK. We
also succeeded in detecting X-ray signals from the 4x4 TES, contrary to the
previous results of 20x20 TES. We further investigated the reasons for the
differences between the 4x4 TES and the 20x20 TES, and present future plans for
improving the multilayer TES array fabrication.


title: Photocarrier relaxation in two-dimensional semiconductors

abstract:
  Two-dimensional (2D) crystals of semiconducting transition metal
dichalcogenides (TMD) absorb a large fraction of incident photons in the
visible frequencies despite being atomically thin. It has been suggested that
the strong absorption is due to the parallel band or "band nesting" effect and
corresponding divergence in the joint density of states. Here, we show using
photoluminescence excitation spectroscopy that the band nesting in mono- and
bilayer MX$_2$ (M = Mo, W and X = S, Se) results in excitation-dependent
characteristic relaxation pathways of the photoexcited carriers. Our
experimental and simulation results reveal that photoexcited electron-hole
pairs in the nesting region spontaneously separate in the $k$-space, relaxing
towards immediate band extrema with opposite momentum. These effects imply that
the loss of photocarriers due to direct exciton recombination is temporarily
suppressed for excitation in resonance with band nesting. Our findings
highlight the potential for efficient hot carrier collection using these
materials as the absorbers in optoelectronic devices.


title:
Nonresonant Hopf-Hopf bifurcation and a chaotic attractor in neutral
  functional differential equations

abstract:
  Nonresonant Hopf-Hopf singularity in neutral functional differential equation
(NFDE) is considered. An algorithm for calculating the third-order normal form
is established by using the formal adjoint theory, center manifold theorem and
the traditional normal form method for RFDE. Van der Pol's equation with
extended delay feedback is studied as an example. The unfoldings near the
Hopf-Hopf bifurcation point is given by applying this algorithm. Periodic
solutions, quasi-periodic solutions are found via theoretical bifurcation
diagram and numerical illustrations. The Hopf-Hopf bifurcation diagram
indicates the possible existence of a chaotic attractor, which is confirmed by
a sequence of simulations.


title: Transductive Learning with Multi-class Volume Approximation

abstract:
  Given a hypothesis space, the large volume principle by Vladimir Vapnik
prioritizes equivalence classes according to their volume in the hypothesis
space. The volume approximation has hitherto been successfully applied to
binary learning problems. In this paper, we extend it naturally to a more
general definition which can be applied to several transductive problem
settings, such as multi-class, multi-label and serendipitous learning. Even
though the resultant learning method involves a non-convex optimization
problem, the globally optimal solution is almost surely unique and can be
obtained in O(n^3) time. We theoretically provide stability and error analyses
for the proposed method, and then experimentally show that it is promising.


title:
A Robust Framework for Moving-Object Detection and Vehicular Traffic
  Density Estimation

abstract:
  Intelligent machines require basic information such as moving-object
detection from videos in order to deduce higher-level semantic information. In
this paper, we propose a methodology that uses a texture measure to detect
moving objects in video. The methodology is computationally inexpensive,
requires minimal parameter fine-tuning and also is resilient to noise,
illumination changes, dynamic background and low frame rate. Experimental
results show that performance of the proposed approach is higher than those of
state-of-the-art approaches. We also present a framework for vehicular traffic
density estimation using the foreground object detection technique and present
a comparison between the foreground object detection-based framework and the
classical density state modelling-based framework for vehicular traffic density
estimation.


title:
Finite time blowup for an averaged three-dimensional Navier-Stokes
  equation

abstract:
  The Navier-Stokes equation on the Euclidean space $\mathbf{R}^3$ can be
expressed in the form $\partial_t u = \Delta u + B(u,u)$, where $B$ is a
certain bilinear operator on divergence-free vector fields $u$ obeying the
cancellation property $\langle B(u,u), u\rangle=0$ (which is equivalent to the
energy identity for the Navier-Stokes equation). In this paper, we consider a
modification $\partial_t u = \Delta u + \tilde B(u,u)$ of this equation, where
$\tilde B$ is an averaged version of the bilinear operator $B$ (where the
average involves rotations and Fourier multipliers of order zero), and which
also obeys the cancellation condition $\langle \tilde B(u,u), u \rangle = 0$
(so that it obeys the usual energy identity). By analysing a system of ODE
related to (but more complicated than) a dyadic Navier-Stokes model of Katz and
Pavlovic, we construct an example of a smooth solution to such a averaged
Navier-Stokes equation which blows up in finite time. This demonstrates that
any attempt to positively resolve the Navier-Stokes global regularity problem
in three dimensions has to use finer structure on the nonlinear portion
$B(u,u)$ of the equation than is provided by harmonic analysis estimates and
the energy identity. We also propose a program for adapting these blowup
results to the true Navier-Stokes equations.


title:
Search for Very-High-Energy Gamma Rays from the z = 0.896 Quasar 4C
  +55.17 with the MAGIC telescopes

abstract:
  The bright gamma-ray quasar 4C +55.17 is a distant source ($z = 0.896$) with
a hard spectrum at GeV energies as observed by the Large Area Telescope (LAT)
on board the {{\it Fermi}} satellite. This source is identified as a good
source candidate for very-high-energy (VHE; $> 30$ GeV) gamma rays. In general
VHE gamma rays from distant sources provide an unique opportunity to study the
extragalactic background light (EBL) and underlying astrophysics. The flux
intensity of this source in the VHE range is investigated. Then, constraints on
the EBL are derived from the attenuation of gamma-ray photons coming from the
distant blazar. We searched for a gamma-ray signal from this object using the
35-hour observations taken by the MAGIC telescopes between November 2010 and
January 2011. No significant VHE gamma-ray signal was detected. We computed the
upper limits of the integrated gamma-ray flux at $95\%$ confidence level of
$9.4 \times 10^{-12}$ cm$^{-2}$ s$^{-1}$ and $2.5 \times 10^{-12}$ cm$^{-2}$
s$^{-1}$ above $100$ GeV and $200$ GeV, respectively. The differential upper
limits in four energy bins in the range from $80$ GeV to $500$ GeV are also
derived. The upper limits are consistent with the attenuation predicted by
low-flux EBL models on the assumption of a simple power-law spectrum
extrapolated from LAT data.


title:
GQM+Strategies: A Comprehensive Methodology for Aligning Business
  Strategies with Software Measurement

abstract:
  In software-intensive organizations, an organizational management system will
not guarantee organizational success unless the business strategy can be
translated into a set of operational software goals. The Goal Question Metric
(GQM) approach has proven itself useful in a variety of industrial settings to
support quantitative software project management. However, it does not address
linking software measurement goals to higher-level goals of the organization in
which the software is being developed. This linkage is important, as it helps
to justify software measurement efforts and allows measurement data to
contribute to higher-level decisions. In this paper, we propose a
GQM+Strategies(R) measurement approach that builds on the GQM approach to plan
and implement software measurement. GQM+Strategies(R) provides mechanisms for
explicitly linking software measurement goals to higher-level goals for the
software organization, and further to goals and strategies at the level of the
entire business. The proposed method is illustrated in the context of an
example application of the method.


title: Sufficiency Condition for KKT Points in Non-smooth Analysis

abstract:
  In this article we consider a convex feasible set described by inequality
constraints that are continuous and not necessarily Lipschitz or convex. We
show that if the Slater constraint qualification and a non-degeneracy condition
are satisfied, then the Karush-Kuhn-Tucker type optimality condition is both
necessary and sufficient. In this way we extend previous results which are
proved for Lipschitz and differentiable inequalities.


title:
Systematic Task Allocation Evaluation in Distributed Software
  Development

abstract:
  Systematic task allocation to different development sites in global software
de- velopment projects can open business and engineering perspectives and help
to reduce risks and problems inherent in distributed development. Relying only
on a single evaluation criterion such as development cost when distributing
tasks to development sites has shown to be very risky and often does not lead
to successful solutions in the long run. Task allocation in global software
projects is challenging due to a multitude of impact factors and constraints.
Systematic allocation decisions require the ability to evaluate and compare
task allocation alternatives and to effectively establish customized task
allocation practices in an organization. In this article, we present a
customizable process for task allocation evaluation that is based on results
from a systematic interview study with practitioners. In this process, the
relevant criteria for evaluating task allocation alternatives are derived by
applying principles from goal-oriented measurement. In addition, the
customization of the process is demonstrated, related work and limitations are
sketched, and an outlook on future work is given.


title:
Performance Analysis and Optimization for Interference Alignment over
  MIMO Interference Channels with Limited Feedback

abstract:
  In this paper, we address the problem of interference alignment (IA) over
MIMO interference channels with limited channel state information (CSI)
feedback based on quantization codebooks. Due to limited feedback and hence
imperfect IA, there are residual interferences across different links and
different data streams. As a result, the performance of IA is greatly related
to the CSI accuracy (namely number of feedback bits) and the number of data
streams (namely transmission mode). In order to improve the performance of IA,
it makes sense to optimize the system parameters according to the channel
conditions. Motivated by this, we first give a quantitative performance
analysis for IA under limited feedback, and derive a closed-form expression for
the average transmission rate in terms of feedback bits and transmission mode.
By maximizing the average transmission rate, we obtain an adaptive feedback
allocation scheme, as well as a dynamic mode selection scheme. Furthermore,
through asymptotic analysis, we obtain several clear insights on the system
performance, and provide some guidelines on the system design. Finally,
simulation results validate our theoretical claims, and show that obvious
performance gain can be obtained by adjusting feedback bits dynamically or
selecting transmission mode adaptively.


title:
Coupling constants of bottom (charmed) mesons with pion from three point
  QCD sum rules

abstract:
  In this article, the three point QCD sum rules is used to compute the strong
coupling constants of vertices containing the strange bottomed ( charmed )
mesons with pion. The coupling constants are calculated, when both the bottom (
charm ) and pion states are off-shell. A comparison of the obtained results of
coupling constants with the existing predictions is also made. Key words:
strong coupling constant, meson, QCD sum rules, bottom, charm.


title: Reaction Mechanisms at MINER$\nu$A

abstract:
  The MINER$\nu$A experiment investigates neutrino interactions with nucleons
needed for an understanding of electroweak interactions of hadrons. Since
nuclear targets are being used many-body effects may affect the extracted cross
sections and the energy reconstruction. The latter is essential for the
extraction of neutrino oscillation properties. We investigate the influence of
nuclear effects on neutrino interaction cross sections and make predictions for
charged current quasielastic (QE) scattering, nucleon-knock-out and pion- and
kaon-production on a CH target. The Giessen Boltzmann--Uehling--Uhlenbeck
(GiBUU) model is used for the description of neutrino-nucleus reactions.
Integrated and differential cross sections for inclusive neutrino scattering,
QE processes and particle production for the MINER$\nu$A neutrino flux are
calculated. The influence of final state interactions on the identification of
these processes is discussed. In particular, energy and $Q^2$ reconstruction
for the MINER$\nu$A flux are critically examined. The $Q^2$ dependence of the
inclusive cross sections is found to be sensitive to the energy reconstruction.
Cut-offs in flux distributions have a large effect. Final state interactions
affect the pion kinetic energy spectra significantly and increase the kaon
cross sections by cross feeding from other channels.


title: From loop clusters and random interlacement to the free field

abstract:
  It was shown by Le Jan that the occupation field of a Poisson ensemble of
Markov loops ("loop soup") of parameter one-half associated to a transient
symmetric Markov jump process on a network is half the square of the Gaussian
free field on this network. We construct a coupling between these loops and the
free field such that an additional constraint holds: the sign of the free field
is constant on each cluster of loops. As a consequence of our coupling we
deduce that the loop clusters of parameter one-half do not percolate on
periodic lattices. We also construct a coupling between the random
interlacement on $\mathbb{Z}^{d}$, $d\geq 3$, introduced by Sznitman, and the
Gaussian free field on the lattice such that the set of vertices visited by the
interlacement is contained in a level set of the free field. We deduce an
inequality between the critical level for the percolation by level sets of the
free field and the critical parameter for the percolation of the vacant set of
the random interlacement. Both in the case of loops and of the random
interlacement, the couplings are constructed by replacing discrete graphs by
metric graphs. Le Jan's and Sznitman's isomorphism theorems between the
Gaussian free field and the occupation field of trajectories can be extended to
the metric graph setting on which the intermediate value principle for
continuous fields holds.


title: A Fixed Point Theorem for Non-Monotonic Functions

abstract:
  We present a fixed point theorem for a class of (potentially) non-monotonic
functions over specially structured complete lattices. The theorem has as a
special case the Knaster-Tarski fixed point theorem when restricted to the case
of monotonic functions and Kleene's theorem when the functions are additionally
continuous. From the practical side, the theorem has direct applications in the
semantics of negation in logic programming. In particular, it leads to a more
direct and elegant proof of the least fixed point result of [Rondogiannis and
W.W.Wadge, ACM TOCL 6(2): 441-467 (2005)]. Moreover, the theorem appears to
have potential for possible applications outside the logic programming domain.


title: Virtual braids from a topological viewpoint

abstract:
  Virtual braids are a combinatorial generalization of braids. We present
abstract braids as equivalence classes of braid diagrams on a surface, joining
two distinguished boundary components. They are identified up to isotopy,
compatibility, stability and Reidemeister moves. We show that virtual braids
are in a bijective correspondence with abstract braids. Finally we demonstrate
that for any abstract braid, its representative of minimal genus is unique up
to compatibility and Reidemeister moves. The genus of such a representative is
thus an invariant for virtual braids. We also give a complete proof of the fact
that there is a bijective correspondence between virtually equivalent virtual
braid diagrams and braid-Gauss diagrams.


title: Preservation of the geometric quantum discord in noisy environments

abstract:
  Geometric description of quantum correlations are favored for their distinct
physical significance. Geometric discord based on the trace distance and the
Bures distance are shown to be well-defined quantum correlation measures. Here,
we examine their particular dynamical behaviors under independent as well as
common structured reservoirs, and reveal their robustness against decoherence.
We showed that the two well-defined geometric discord may be preserved well, or
even be improved and generated by the noisy process of the common reservoir.
Moreover, we also provided a strategy for long-time preservation of these two
geometric discord in independent reservoirs.


title: l_p-norm based James-Stein estimation with minimaxity and sparsity

abstract:
  A new class of minimax Stein-type shrinkage estimators of a multivariate
normal mean is studied where the shrinkage factor is based on an l_p norm. The
proposed estimators allow some but not all coordinates to be estimated by 0
thereby allow sparsity as well as minimaxity.


title: Rational Points on the Fermat Cubic Surface

abstract:
  We prove a lower bound that agrees with Manin's prediction for the number of
rational points of bounded height on the Fermat cubic surface. As an
application we provide a simple counterexample to Manin's conjecture over the
rationals.


title: Compact planes, mostly 8-dimensional. A retrospect

abstract:
  Results on $8$-dimensional topological planes are scattered in the
literature. It is the aim of the present paper to give a survey of these
geometries, in particular of information obtained after the appearance of the
treatise Compact Projective Planes or not included in this book. For some
theorems new proofs are given and a few related results concerning planes of
other dimensions are presented.


title:
Anomalous Josephson effect induced by spin-orbit interaction and Zeeman
  effect in semiconductor nanowires

abstract:
  We investigate theoretically the Josephson junction of semiconductor nanowire
with strong spin-orbit (SO) interaction in the presence of magnetic field. By
using a tight-binding model, the energy levels $E_n$ of Andreev bound states
are numerically calculated as a function of phase difference $\varphi$ between
two superconductors in the case of short junctions. The DC Josephson current is
evaluated from the Andreev levels. In the absence of SO interaction, a
$0$-$\pi$ transition due to the magnetic field is clearly observed. In the
presence of SO interaction, the coexistence of SO interaction and Zeeman effect
results in $E_n (-\varphi) \ne E_n (\varphi)$, where the anomalous Josephson
current flows even at $\varphi =0$. In addition, the direction-dependence of
critical current is observed, in accordance with experimental results.


title:
Shell and alpha cluster structures in 8Be with tensor-optimized shell
  model

abstract:
  We study the shell and alpha cluster structures in the ground and excited
states of 8Be in terms of the tensor-optimized shell model (TOSM). In TOSM, the
tensor correlation is optimized in the full space of 2p2h configurations
involving high-momentum components. The short-range correlation is treated with
the unitary correlation operator method (UCOM). We use the effective
interaction based on the bare nucleon-nucleon interaction AV8$^\prime$. The 8Be
states consist of two groups of ground band states and highly excited states
with the isospin T=0 and T=1. It is found that the tensor contributions of the
ground band states are stronger than the highly excited states and that the
kinetic energies and the central contributions of the ground band states are
almost twice the 4He values. These features suggest two-alpha clustering for
the ground band states in 8Be. We also estimate the correlation energy of the
$\alpha$ clustering using the alpha cluster model. In the highly excited
states, the calculated spectrum in TOSM reproduces the experimental level order
and the relative energies of each level. This agreement suggests that those
states can be interpreted as shell-like states. The level order is found to be
sensitive to the presence of the tensor force in comparison with the results
using the Minnesota effective interaction without the tensor force. It is also
found that the tensor contributions in the T=0 states are stronger than the T=1
states, which is consistent with the state dependence of the tensor force.


title:
Self-induced Spatial Dynamics to Enhance Spin-Squeezing via One-Axis
  Twisting in a Two-Component Bose-Einstein Condensate

abstract:
  We theoretically investigate a scheme to enhance spin squeezing in a
two-component Bose-Einstein condensate (BEC) by utilizing the inherent
mean-field dynamics of the condensate. Due to the asymmetry in the scattering
lengths, the two components exhibit density oscillations where they spatially
separate and recombine. The effective non-linearity responsible for spin
squeezing is increased by up to three orders of magnitude when the two
components spatially separate \cite{treutlein2010}. We perform a multi-mode
simulation of the system using the truncated Wigner method, and show that this
method can be used to create significant spin squeezing in systems where the
effective nonlinearity would ordinarily be too small, and that strong spatial
dynamics resulting from large particle numbers aren't necessarily detrimental
to generating spin-squeezing. We develop a simplified semi-analytic model that
gives good agreement with our multi-mode simulation, and will be useful for
predicting spin-squeezing in a range of different systems.


title:
Polarization parameters of the quasi--elastic (p,2p) reaction with
  nuclei at 1 GeV

abstract:
  New experomental data on polarization and spin--correlation parameters in the
(p,2p) reaction with nuclei are presented. The experiment was aimed to study a
modification of the proton--proton scattering matrix.


title:
Impurity transport in Alcator C-Mod in the presence of poloidal density
  variation induced by ion cyclotron resonance heating

abstract:
  Impurity particle transport in an ion cyclotron resonance heated Alcator
C-Mod discharge is studied with local gyrokinetic simulations and a theoretical
model including the effect of poloidal asymmetries and elongation. In spite of
the strong minority temperature anisotropy in the deep core region, the
poloidal asymmetries are found to have a negligible effect on the turbulent
impurity transport due to low magnetic shear in this region, in agreement with
the experimental observations. According to the theoretical model, in outer
core regions poloidal asymmetries may contribute to the reduction of the
impurity peaking, but uncertainties in atomic physics processes prevent
quantitative comparison with experiments.


title:
Atomistic tight-binding study of electronic structure and interband
  optical transitions in GaBi$_{x}$As$_{1-x}$/GaAs quantum wells

abstract:
  Large-supercell tight-binding calculations are presented for
GaBi$_{x}$As$_{1-x}$/GaAs single quantum wells (QWs) with Bi fractions $x$ of
3.125% and 12.5%. Our results highlight significant distortion of the valence
band states due to the alloy disorder. A large full-width-half-maximum (FWHM)
is estimated in the ground state interband transition energy ($\approx$ 33 meV)
at 3.125% Bi, consistent with recent photovoltage measurements for similar Bi
compositions. Additionally, the alloy disorder effects are predicted to become
more pronounced as the QW width is increased. However, they are less strong at
the higher Bi composition (12.5%) required for the design of temperature-stable
lasers, with a calculated FWHM of $\approx$ 23.5 meV at $x$=12.5%.


title: Morphism complexes of sets with relations

abstract:
  Let $r$ be a positive integer. An $r$-set is a pair $X= (V(X),R(X))$
consisting of a set $V(X)$ with a subset $R(X)$ of the direct product $V(X)^r$.
The object of this paper is to investigate the Hom complexes of $r$-sets, which
were introduced for graphs in the context of the graph coloring problem.
  In the first part, we introduce simplicial sets which we call singular
complexes, and show that singular complexes and Hom complexes are naturally
homotopy equivalent. The second part is devoted to the generalization of
$\times$-homotopy theory established by Dochtermann. We show the folding
theorem for hypergraphs which was partly proved by Iriye and Kishimoto.


title:
Near Earth Object 2012XJ112 as a source of bright bolides of achondritic
  nature

abstract:
  We analyze the likely link between the recently discovered Near Earth Object
2012XJ112 and a bright fireball observed over the south of Spain on December
27, 2012. The bolide, with an absolute magnitude of -9 +- 1, was simultaneously
imaged during the morning twilight from two meteor stations operated by the
SPanish Meteor Network (SPMN). It was also observed by several casual
witnesses. The emission spectrum produced during the ablation of the meteoroid
in the atmosphere was also recorded. From its analysis the chemical nature of
this particle was inferred. Although our orbital association software
identified several potential parent bodies for this meteoroid, the analysis of
the evolution of the orbital elements performed with the Mercury 6 symplectic
integrator supports the idea that NEO 2012XJ112 is the source of this
meteoroid. The implications of this potential association are discussed here.
In particular, the meteoroid bulk chemistry is consistent with a basaltic
achondrite, and this emphasizes the importance to deduce from future Earth
approaches the reflectance spectrum and taxonomic nature of 2012XJ112.


title:
Rate-Distortion Properties of Single-Layer Quantize-and-Forward for
  Two-Way Relaying

abstract:
  The Quantize & Forward (QF) scheme for two-way relaying is studied with a
focus on its rate-distortion properties. A sum rate maximization problem is
formulated and the associated quantizer optimization problem is investigated.
An algorithm to approximately solve the problem is proposed. Under certain
cases scalar quantizers maximize the sum rate.


title:
Equation-Free Analysis of Macroscopic Behavior in Traffic and Pedestrian
  Flow

abstract:
  Equation-free methods make possible an analysis of the evolution of a few
coarse-grained or macroscopic quantities for a detailed and realistic model
with a large number of fine-grained or microscopic variables, even though no
equations are explicitly given on the macroscopic level. This will facilitate a
study of how the model behavior depends on parameter values including an
understanding of transitions between different types of qualitative behavior.
These methods are introduced and explained for traffic jam formation and
emergence of oscillatory pedestrian counter flow in a corridor with a narrow
door.


title:
Novel zone formation due to interplay between sedimentation and phase
  ordering

abstract:
  Usually, we expect large particles to sediment faster than small of the same
material. Contrary to this intuition, we report a dynamical competition between
sedimentation and phase ordering which leads to smaller particles settling
faster than larger ones. We access this phenomenon using suspensions of
polymers and two colloidal species which we image with confocal microscopy.
Polymers mediate attractions between colloids, leading to phase separation and
crystallisation. We find that the dynamical interplay between sedimentation,
phase separation and crystal nucleation underlie this phenomenon. Furthermore,
under certain conditions we find a kinetic pathway leading to an apparent
coexistence between a one component crystal and binary fluid of equal buoyancy.
These findings may be relevant to the basic understanding of
sedimentation-induced zone formation in nature and industrial applications.


title:
Connecting the Sun and the Solar Wind: The Self-consistent Transition of
  Heating Mechanisms

abstract:
  We have performed a 2.5 dimensional magnetohydrodynamic simulation that
resolves the propagation and dissipation of Alfven waves in the solar
atmosphere. Alfvenic fluctuations are introduced on the bottom boundary of the
extremely large simulation box that ranges from the photosphere to far above
the solar wind acceleration region. Our model is ab initio in the sense that no
corona and no wind are assumed initially.The numerical experiment reveals the
quasi-steady solution that has the transition from the cool to the hot
atmosphere and the emergence of the high speed wind. The global structure of
the resulting hot wind solution fairly well agree with the coronal and the
solar wind structure inferred from observations. The purpose of this study is
to complement the previous paper by Matsumoto & Suzuki (2012) and describe the
more detailed results and the analysis method. These results include the
dynamics of the transition region and the more precisely measured heating rate
in the atmosphere. Particularly, the spatial distribution of the heating rate
helps us to interpret the actual heating mechanisms in the numerical
simulation.Our estimation method of heating rate turned out to be a good
measure for dissipation of Alfven waves and low beta fast waves.


title:
Existence and uniqueness of Chern connection in the Klein-Grifone
  approach

abstract:
  The Klein-Grifone approach to global Finsler geometry is adopted. A global
existence and uniqueness theorem for Chern connection is formulated and proved.
The torsion and curvature tensors of Chern connection are derived. Some
properties and the Bianchi identities for this connection are investigated. A
concise comparison between Berwald, Cartan and Chern connections is presented.


title: Transmission-phase of an electron in a quantum point contact

abstract:
  For the first time we calculate the electron transmission phase through a
quantum point contact (QPC). The QPC is considered in the saddle point
approximation in the single-electron picture. We show that when the electron
energy is close to the height of the potential barrier the transmission-phase
depends linearly on the energy. The coefficient in the linear dependence is
logarithmically enhanced by the ratio of the height over the curvature of the
barrier potential. We compare the calculated transmission phase with the first
experimental measurements of the phase.


title:
Fractional fundamental lemma and fractional integration by parts formula
  -- Applications to critical points of Bolza functionals and to linear
  boundary value problems

abstract:
  In the first part of the paper, we prove a fractional fundamental (du
Bois-Reymond) lemma and a fractional variant of the integration by parts
formula. The proof of the second result is based on an integral representation
of functions possessing Riemann-Liouville fractional derivatives, derived in
this paper too.
  In the second part of the paper, we use the previous results to give
necessary optimality conditions of Euler-Lagrange type (with boundary
conditions) for fractional Bolza functionals and to prove an existence result
for solutions of linear fractional boundary value problems. In the last case we
use a Hilbert structure and the Stampacchia theorem.


title:
2 + 1 dimensional gravity from Maxwell and semi-simple extension of the
  Poincare gauge symmetric models

abstract:
  We obtain 2 + 1 dimensional gravity with cosmological constant which is
coupled to gauge fields, using Maxwell and semi-simple extension of the
Poincare gauge symmetric models (i.e. Chern-Simons models with these gauge
groups). Also, we obtain some Ads and BTZ type solutions for the classical
equations of motion for these 2 + 1 dimensional gravities. For the semi-simple
extension of the Poincare gauge group we investigate the Ads/CFT correspondence
and show that the model at the boundary is equivalent to the sum of three WZW
models over group SO(2,1). Then, we show that the central charge of the CFT is
the same as that of CFT at the boundary of Ads spacetime related to the
Chern-Simons model with gauge group SO(2,2). Finally, we show that these two 2
+ 1 dimensional gravity models are dual (canonically transformed) to each
other.


title: Interpretation of AMS-02 electrons and positrons data

abstract:
  We perform a combined analysis of the recent AMS-02 data on electrons,
positrons, electrons plus positrons and positron fraction, in a self-consistent
framework where we realize a theoretical modeling of all the astrophysical
components that can contribute to the observed fluxes in the whole energy
range. The primary electron contribution is modeled through the sum of an
average flux from distant sources and the fluxes from the local supernova
remnants in the Green catalog. The secondary electron and positron fluxes
originate from interactions on the interstellar medium of primary cosmic rays,
for which we derive a novel determination by using AMS-02 proton and helium
data. Primary positrons and electrons from pulsar wind nebulae in the ATNF
catalog are included and studied in terms of their most significant (while
loosely known) properties and under different assumptions (average contribution
from the whole catalog, single dominant pulsar, a few dominant pulsars). We
obtain a remarkable agreement between our various modeling and the AMS-02 data
for all types of analysis, demonstrating that the whole AMS-02 leptonic data
admit a self-consistent interpretation in terms of astrophysical contributions.


title:
Parameters of two low-mass contact eclipsing binaries near the
  short-period limit

abstract:
  The two objects 1SWASP J150822.80-054236.9 and 1SWASP J160156.04+202821.6
were initially detected from their SuperWASP archived light curves as candidate
eclipsing binaries with periods close to the short-period cut-off of the
orbital period distribution of main sequence binaries, at ~0.2 d. Here, using
INT spectroscopic data, we confirm them as double-lined spectroscopic and
eclipsing binaries, in contact configuration. Following modelling of their
visual light curves and radial velocity curves, we determine their component
and system parameters to precisions between ~2 and 11%. The former system
contains 1.07 and 0.55 M_sun components, with radii of 0.90 and 0.68 R_sun
respectively; its primary exhibits pulsations with period 1/6 the orbital
period of the system. The latter contains 0.86 and 0.57 M_sun components, with
radii of 0.75 and 0.63R_sun respectively.


title: On Deeply Virtual Compton Scattering at next-to-leading order

abstract:
  Deeply Virtual Compton Scattering in the near forward kinematic region is the
golden access to Generalized Parton Distributions. We studied the O(alphaS)
corrections to the scattering amplitude for both spacelike and timelike
kinematics relevant respectively to the leptoproduction of a real photon and to
the photoproduction of a lepton pair. It turns out that these corrections are
phenomenologically important and that the gluonic contributions are by no means
negligible, even in the moderate energy range of JLab12 and of the COMPASS-II
experiment at CERN.


title:
Extremely quick thermalization in a macroscopic quantum system for a
  typical nonequilibrium subspace

abstract:
  The fact that macroscopic systems approach thermal equilibrium may seem
puzzling, for example, because it may seem to conflict with the
time-reversibility of the microscopic dynamics. We here prove that in a
macroscopic quantum system for a typical choice of "nonequilibrium subspace",
any initial state indeed thermalizes, and in fact does so very quickly, on the
order of the Boltzmann time $\tau_\mathrm{B}:=h/(k_\mathrm{B}T)$. Therefore
what needs to be explained is, not that macroscopic systems approach
equilibrium, but that they do so slowly.

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


title:
Spin-density-wave-induced anomalies in the optical conductivity of
  AFe2As2, (A=Ca, Sr, Ba) single-crystalline iron pnictides

abstract:
  We report the complex dielectric function of high-quality
$A\textrm{Fe}_2\textrm{As}_2$, ($A$=Ca, Sr, Ba) single crystals with
$T_{\mathrm{N}}\approx150\ \textrm{K}$, $200\ \textrm{K}$, and $138\
\textrm{K}$, respectively, determined by broadband spectroscopic ellipsometry
at temperatures $10\leq T\leq300\ \textrm{K}$ and wavenumbers from $100\
\textrm{cm}^{-1}$ to $52000\ \textrm{cm}^{-1}$. In
$\textrm{CaFe}_2\textrm{As}_2$ we identify the optical spin-density--wave gap
$2\Delta_{\mathrm{SDW}}\approx1250\ \textrm{cm}^{-1}$. The
$2\Delta_{\mathrm{SDW}}/(k_{\mathrm{B}}T_{\mathrm{N}})$ ratio, characterizing
the strength of the electron-electron coupling in the spin-density--wave state,
amounts to $\approx12$ in $\textrm{CaFe}_2\textrm{As}_2$, significantly larger
than the corresponding values for the $\textrm{SrFe}_2\textrm{As}_2$ and
$\textrm{BaFe}_2\textrm{As}_2$ compounds: 8.7 and 5.3, respectively. We further
show that, similarly to the Ba-based compound, two characteristic SDW energy
gaps can be identified in the infrared-conductivity spectra of both
$\textrm{SrFe}_2\textrm{As}_2$ and $\textrm{CaFe}_2\textrm{As}_2$ and
investigate their detailed temperature dependence in all three materials. This
analysis reveals the existence of an anomaly in $\textrm{CaFe}_2\textrm{As}_2$
at a temperature $T^*\approx80\ \textrm{K}$, well below the N\'eel temperature
of this compound, which implies weak coupling between the two SDW subsystems.
The coupling between the two subsystems evolves to intermediate in the Sr-based
and strong in the Ba-based material. The temperature dependence of the infrared
phonons reveals clear anomalies at the corresponding N\'eel temperatures of the
investigated compounds. In $\textrm{CaFe}_2\textrm{As}_2$, the phonons exhibit
signatures of SDW fluctuations above $T_N$ and some evidence for anomalies at
$T^*$. (full abstract in PDF)


title:
Cold gas properties of the Herschel Reference Survey. III. Molecular gas
  stripping in cluster galaxies

abstract:
  The HRS is a complete volume-limited sample of nearby objects including Virgo
cluster and isolated objects. Using a recent compilation of HI and CO data we
study the effects of the cluster on the molecular gas content of spiral
galaxies. We first identify M* as the scaling variable that traces the total H2
mass of galaxies better. We show that, on average, HI-deficient galaxies are
significantly offset from the M(H2) vs. M* relation for HI-normal galaxies. We
use the M(H2) vs. M* scaling relation to define the H2-deficiency parameter.
This parameter shows a weak and scattered relation with the HI-def, here taken
as a proxy for galaxy interactions with the cluster environment. We also show
that, as for the HI, the extent of the H2 disc decreases with increasing
HI-deficiency. These results show that cluster galaxies have, on average, a
lower H2 content than similar objects in the field. The slope of the H2-def vs.
HI-def relation is less than 1, while the D(HI)/D(i) vs. HI-def relation is
steeper than the D(CO)/D(i) vs. HI-def relation, thereby indicating that the H2
gas is removed less efficiently than the HI. This result can be understood if
the HI is distributed on a flat disc more extended than the stellar disc, thus
less anchored to the gravitational potential well of the galaxy than the H2.
There is a clear trend between the NUV-i colour and H2-def, which suggests that
H2 removal quenches the activity of star formation. This causes galaxies
migrate from the blue cloud to the green valley and, eventually, to the red
sequence. The total gas-consumption timescale of gas deficient cluster galaxies
is comparable to that of isolated systems, and is significantly larger than the
typical timescale for total gas removal in a ram pressure stripping process,
thus suggesting that ram pressure, rather than starvation, is the dominant
process driving the evolution of these cluster galaxies.


title: Spectrum Allocation for ICIC Based Picocell

abstract:
  In this work, we analytically study the impact of spectrum allocation scheme
in picocells on the coverage probability (CP) of the Pico User (PU), when the
macro base stations (MBSs) employ either fractional frequency reuse (FFR) or
soft frequency reuse (SFR). Assuming a fixed size for the picocell, the CP
expression is derived for a PU present in either a FFR or SFR based deployment,
and when the PU uses either the centre or the edge frequency resources. Based
on these expressions, we propose two possible frequency allocation schemes for
the picocell when FFR is employed by the macrocell. The CP and the average rate
expressions for both these schemes are derived, and it is shown that these
schemes outperform the conventional scheme where no inter-cell interference
coordination (ICIC) is assumed. The impact of both schemes on the macro-user
performance is also analysed. When SFR is used by the MBS, it is shown that the
CP is maximized when the PU uses the same frequency resources as used by the
centre region.


title: $\mathbb{Z}_3\times \mathbb{Z}_3$ crossed products

abstract:
  Let $A$ be the generic abelian crossed product with respect to
$\mathbb{Z}_3\times \mathbb{Z}_3$, in this note we show that $A$ is similar to
the tensor product of 4 symbol algebras (3 of degree 9 and one of degree 3) and
if $A$ is of exponent $3$ it is similar to the product of 31 symbol algebras of
degree $3$. We then use \cite{RS} to prove that if $A$ is any algebra of degree
$9$ then $A$ is similar to the product of $35840$ symbol algebras ($8960$ of
degree $3$ and $26880$ of degree $9$) and if $A$ is of exponent $3$ it is
similar to the product of $277760$ symbol algebras of degree $3$. We then show
that the essential $3$-dimension of the class of $A$ is at most $6$.


title: Twisted magnetic flux tubes in the solar wind

abstract:
  Magnetic flux tubes in the solar wind can be twisted as they are transported
from the solar surface, where the tubes are twisted owing to photospheric
motions. It is suggested that the twisted magnetic tubes can be detected as the
variation of total (thermal+magnetic) pressure during their passage through
observing satellite. We show that the total pressure of several observed
twisted tubes resembles the theoretically expected profile. The twist of
isolated magnetic tube may explain the observed abrupt changes of magnetic
field direction at tube walls. We have also found some evidence that the flux
tube walls can be associated with local heating of the plasma and elevated
proton and electron temperatures. For the tubes aligned with the Parker spiral,
the twist angle can be estimated from the change of magnetic field direction.
Stability analysis of twisted tubes shows that the critical twist angle of the
tube with a homogeneous twist is 70$^0$, but the angle can further decrease
owing to the motion of the tube with regards to the solar wind stream. The
tubes with a stronger twist are unstable to the kink instability, therefore
they probably can not reach 1 AU.


title: Sequential Monte Carlo for Graphical Models

abstract:
  We propose a new framework for how to use sequential Monte Carlo (SMC)
algorithms for inference in probabilistic graphical models (PGM). Via a
sequential decomposition of the PGM we find a sequence of auxiliary
distributions defined on a monotonically increasing sequence of probability
spaces. By targeting these auxiliary distributions using SMC we are able to
approximate the full joint distribution defined by the PGM. One of the key
merits of the SMC sampler is that it provides an unbiased estimate of the
partition function of the model. We also show how it can be used within a
particle Markov chain Monte Carlo framework in order to construct
high-dimensional block-sampling algorithms for general PGMs.


title:
A Semi-Linear Backward Parabolic cauchy Problem with Unbounded
  Coefficients of Hamilton-Jacobi-Bellman Type and Applications to optimal
  control

abstract:
  We obtain weighted uniform estimates for the gradient of the solutions to a
class of linear parabolic Cauchy problems with unbounded coefficients. Such
estimates are then used to prove existence and uniqueness of the mild solution
to a semi-linear backward parabolic Cauchy problem, where the differential
equation is the Hamilton-Jacobi-Bellman equation of a suitable optimal control
problem. Via backward stochastic differential equations, we show that the mild
solution is indeed the Value Function of the controlled equation and that the
feedback law is verified.


title: Symbol length in the Brauer group of a field

abstract:
  We bound the symbol length of elements in the Brauer group of a field $K$
containing a $C_m$ field (for example any field containing an algebraically
closed field or a finite field), and solve the local exponent-index problem for
a $C_m$ field $F$. In particular, for a $C_m$ field $F$, we show that every $F$
central simple algebra of exponent $p^t$ is similar to the tensor product of at
most $len(p^t,F)\leq t(p^{m-1}-1)$ symbol algebras of degree $p^t$. We then use
this bound on the symbol length to show that the index of such algebras is
bounded by $(p^t)^{(p^{m-1}-1)}$, which in turn gives a bound for any algebra
of exponent $n$ via the primary decomposition. Finally for a field $K$
containing a $C_m$ field $F$, we show that every $F$ central simple algebra of
exponent $p^t$ and degree $p^s$ is similar to the tensor product of at most
$len(p^t,p^s,K)\leq len(p^t,L)$ symbol algebras of degree $p^t$, where $L$ is a
$C_{m+ed_L(A)+p^{s-t}-1}$ field.


title:
A von Staudt-type formula for $\displaystyle{\sum_{z\in\mathbb{Z}_n[i]}
  z^k }$

abstract:
  In this paper we study the sum of powers in the Gaussian integers
$\mathbf{G}_k(n):=\sum_{a,b \in [1,n]} (a+b i)^k$. We give an explicit formula
for $\mathbf{G}_k(n) \pmod n $ in terms of the prime numbers $p \equiv 3 \pmod
4$ with $p \mid \mid n$ and $p-1 \mid k$, similar to the well known one due to
von Staudt for $\sum_{i=1}^n i^k \pmod n$. We apply this formula to study the
set of integers $n$ which divide $\mathbf{G}_n(n)$ and compute its asymptotic
density with six exact digits: $0.971000\ldots$.


title: Category O for the Schr\"odinger algebra

abstract:
  We study category O for the (centrally extended) Schr\"odinger algebra. We
determine the quivers for all blocks and relations for blocks of nonzero
central charge. We also describe the quiver and relations for the finite
dimensional part of O. We use this to determine the center of the universal
enveloping algebra and annihilators of Verma modules. Finally, we classify
primitive ideals with nonzero central charge.


title:
Distributed manipulation of two-qubit entanglement with coupled
  continuous variables

abstract:
  We study the dynamics of two qubits separately sent through two coupled
resonators, each initially containing a coherent state field. We present
analytical arguments and numerical calculations for the qubit-field system
under different two-qubit initial states, photon hopping strengths, and
detunings. In far off-resonant regime, the maximal entanglement of two qubits
can be generated with the initial qubit state in which one qubit is in the
excited state and the other is in the ground state, and the initially maximal
two-qubit entanglement can be frozen and fully revived even for large mean
photon number. When the qubits are both initially in their excited states or
ground states, the qubit-qubit entanglement birth and death apparently appear
in the regime where the photon hopping strength is close to qubit-field
detuning, and its peaks do not decrease monotonically as the interaction time
increases. It is interesting to observe that when there is photon hopping
strength between two fields, the field-field entanglement can be larger than
one and increases as the initial amplitude of the coherent state grows. By
postselecting the fields both in their coherent states, the entanglement of two
initially unentangled qubits can be largely improved. Our present setup is
fundamental for the distributed quantum information processing and applicable
to different physical qubit-resonator systems.


title:
Residue Family Operators on Spinors and Spectral Theory of Dirac
  operator on Poincar\'e-Einstein Spaces

abstract:
  We study conformal $Spin$-subgeometry of submanifolds in a semi-Riemannian
$Spin$-manifold, focusing on conformal $Spin$-manifolds $(M,[h])$ and their
Poincar\'e-Einstein metrics $(X,g_+)$. Our approach is based on the spectral
theory of Dirac operator in the ambient $Spin$-manifold, and associated spinor
valued meromorphic family of distributions with residues given by the residue
family operators $\slashed{D}_N^{res}(h;\lambda)$ on spinors. We develop basic
aspects and properties of $\slashed{D}_N^{res}(h;\lambda)$ including conformal
covariance, factorization properties by conformally covariant operators for
both flat and curved semi-Riemannian $Spin$-manifolds, and Poisson
transformation.


title:
A hemispherical dynamo model : Implications for the Martian crustal
  magnetization

abstract:
  Mars Global Surveyor measurements revealed that the Martian crust is strongly
magnetized in the southern hemisphere while the northern hemisphere is
virtually void of magnetization. Two possible reasons have been suggested for
this dichotomy: A once more or less homogeneously magnetization may have been
destroyed in the northern hemisphere by, for example, resurfacing or impacts.
The alternative theory we further explore here assumes that the dynamo itself
produced a hemispherical field. We use numerical dynamo simulations to study
under which conditions a spatial variation of the heat flux through the
core-mantle boundary (CMB) may yield a strongly hemispherical surface field. We
assume that the early Martian dynamo was exclusively driven by secular cooling
and we mostly concentrate on a cosine CMB heat flux pattern with a minimum at
the north pole, possibly caused by the impacts responsible for the northern
lowlands. This pattern consistently triggers a convective mode which is
dominated by equatorially anti-symmetric and axisymmetric (EAA) thermal winds.
Convective up- and down-wellings and thus radial magnetic field production then
tend to concentrate in the southern hemisphere which is still cooled
efficiently while the northern hemisphere remains hot. The dynamo changes from
an alpha^2- for a homogeneous CMB heat flux to an alpha-Omega-type in the
hemispherical configuration. These dynamos reverse on time scales of about 10
kyrs. This too fast to allow for the more or less unidirectional magnetization
of thick crustal layer required to explain the strong magnetization in the
southern hemisphere.


title: MHD modeling of coronal loops: the transition region throat

abstract:
  The expansion of coronal loops in the transition region may considerably
influence the diagnostics of the plasma emission measure. The cross sectional
area of the loops is expected to depend on the temperature and pressure, and
might be sensitive to the heating rate. The approach here is to study the area
response to slow changes in the coronal heating rate, and check the current
interpretation in terms of steady heating models. We study the area response
with a time-dependent 2D MHD loop model, including the description of the
expanding magnetic field, coronal heating and losses by thermal conduction and
radiation from optically thin plasma. We run a simulation for a loop 50 Mm long
and quasi-statically heated to about 4 MK. We find that the area can change
substantially with the quasi-steady heating rate, e.g. by ~40% at 0.5 MK as the
loop temperature varies between 1 and 4 MK, and, therefore, affects the
interpretation of DEM(T) curves.


title:
Exact solution of the $p_x + ip_y$ pairing Hamiltonian by deforming the
  pairing algebra

abstract:
  The present paper makes a connection between collective bosonic states and
the exact solutions of the $p_x + ip_y$ pairing Hamiltonian. This makes it
possible to investigate the effects of the Pauli principle on the energy
spectrum, by gradually reintroducing the Pauli principle. It also introduces an
efficient and stable numerical method to probe all the eigenstates of this
class of Hamiltonians.


title: All dihedral division algebras of degree five are cyclic

abstract:
  Rowen and Saltman proved that every division algebra which is split by a
dihedral extension of degree $2n$ of the center, $n$ odd, is in fact cyclic.
The proof requires roots of unity of order $n$ in the center. We show that for
$n=5$, this assumption can be removed. It then follows that
${}_{5\!\!\!\:}Br(F)$, the $5$-torsion part of the Brauer group, is generated
by cyclic algebras, generalizing a result of Merkurjev on the $2$ and $3$
torsion parts.


title: Metric ultraproducts of finite simple groups

abstract:
  Some new results on metric ultraproducts of finite simple groups are
presented. Suppose that G is such a group, defined in terms of a non-principal
ultrafilter {\omega} on N and a sequence {(G_i)_{i \in N}} of finite simple
groups, and that G is neither finite nor a Chevalley group over an infinite
field. Then G is isomorphic to an ultraproduct of alternating groups or to an
ultraproduct of finite simple classical groups. The isomorphism type of G
determines which of these two cases arises, and, in the latter case, the
{\omega}-limit of the characteristics of the groups Gi. Moreover G is a
complete path-connected group with respect to the natural metric on G.


title:
Exact steady state manifold of a boundary driven spin-1 Lai-Sutherland
  chain

abstract:
  We present an explicit construction of a family of steady state density
matrices for an open integrable spin-1 chain with bilinear and biquadratic
interactions, also known as the Lai-Sutherland model, driven far from
equilibrium by means of two oppositely polarizing Markovian dissipation
channels localized at the boundary. The steady state solution exhibits n+1 fold
degeneracy, for a chain of length n, due to existence of (strong) Liouvillian
U(1) symmetry. The latter can be exploited to introduce a chemical potential
and define a grand canonical nonequilibrium steady state ensemble. The matrix
product form of the solution entails an infinitely-dimensional representation
of a non-trivial Lie algebra (semidirect product of sl_2 and a non-nilpotent
radical) and hints to a novel Yang-Baxter integrability structure.

categories: quant-ph cond-mat.stat-mech cond-mat.str-el nlin.SI


title: Hemispherical Parker waves driven by thermal shear in planetary dynamos

abstract:
  Planetary and stellar magnetic fields are thought to be sustained by helical
motions ($\alpha$-effect) and, if present, differential rotation
($\Omega$-effect). In the Sun, the strong differential rotation in the
tachocline is responsible for an efficient $\Omega$-effect creating a strong
axisymmetric azimuthal magnetic field. This is a prerequisite for Parker dynamo
waves that may be responsible for the solar cycle. In the liquid iron cores of
terrestrial planets, the Coriolis force organizes convection into columns with
a strong helical flow component. These likely dominate magnetic field
generation while the $\Omega$-effect is of secondary importance. Here we use
numerical simulations to show that the planetary dynamo scenario may change
when the heat flux through the outer boundary is higher in one hemisphere than
in the other. A hemispherical dynamo is promoted that is dominated by fierce
thermal wind responsible for a strong $\Omega$-effect. As a consequence Parker
dynamo waves are excited equivalent to those predicted for the Sun. They obey
the same dispersion relation and propagation characteristics. We suggest that
Parker waves may therefore also play a role in planetary dynamos for all
scenarios where zonal flows become an important part of convective motions.


title: Formes quadratiques de discriminants embo\^it\'es

abstract:
  Quadratic forms with embedded discriminants. Integral binary quadratic forms
have multiple applications, for example in factorization or cryptography. The
Nice family of cryptographic systems makes use of quadratic forms with
different discriminants $\pm p$, and $\pm pq^2$ where $p$, $q$ are large
primes. This paper shows the precise links between forms with $D$ discriminant
and forms with $Df^2$ discriminant, which are crucial in the analysis of the
systems Nice and theirs attacks. We also introduce the notion of
semi-equivalence of binary quadratic forms, and give some characterizations of
semi-equivalent forms, which are useful in the analysis of these attacks.
  -----
  Les formes quadratiques binaires fournissent un moyen explicite pour
manipuler des id\'eaux de corps quadratiques, et leurs applications pratiques
sont multiples. De nombreux algorithmes de factorisation les utilisent. Elle
sont aussi utilis\'ees en cryptographie, en particulier pour les syst\`emes
Nice. Les syst\`emes de chiffrement Nice utilisent des formes quadratiques de
discriminants $\pm p$ et $\pm pq^2$ o\`u $p$ et $q$ sont des nombres premiers.
Cet article pr\'ecise les liens entre les formes de discriminant $D$ et celles
de discriminant $Df^2$, ce qui est essentiel pour l'analyse de Nice et de ses
attaques. Il introduit aussi la notion de formes quadratiques
semi-\'equivalentes et en explicite plusieurs caract\'erisations, utiles pour
l'analyse de ces attaques.


title:
Investigating the sensitivity of observed spectral energy distributions
  to clumpy torus properties in Seyfert galaxies

abstract:
  We present nuclear spectral energy distributions (SEDs) from 1 to 18 micron
of a small sample of nearby, nearly face-on and undisturbed Seyfert galaxies
without prominent nuclear dust lanes. These nuclear SEDs probe the central ~35
pc of the galaxies, on average, and include photometric and spectroscopic
infrared (IR) data. We use these SEDs, the clumpy torus models of Nenkova et
al. and a Bayesian approach to study the sensitivity of different IR
wavelengths to the torus parameters. We find that high angular resolution 8-13
micron spectroscopy alone reliably constrains the number of clumps and their
optical depth (N0 and tau_V). On the other hand, we need a combination of mid-
and near-IR subarcsecond resolution photometry to constrain torus width and
inclination, as well as the radial distribution of the clouds (sigma, i and q).
For flat radial profiles (q=0,1), it is possible to constrain the extent of the
mid-IR-emitting dust within the torus (Y) when N-band spectroscopy is
available, in addition to near-IR photometry. Finally, by fitting different
combinations of average and individual Seyfert 1 and Seyfert 2 data, we find
that, in general, for undisturbed, nearly face-on Seyferts without prominent
nuclear dust lanes, the minimum combination of data necessary to reliably
constrain all the torus parameters is J+K+M-band photometry + N-band
spectroscopy.


title:
Bayesian Inference Methods for Univariate and Multivariate GARCH Models:
  a Survey

abstract:
  This survey reviews the existing literature on the most relevant Bayesian
inference methods for univariate and multivariate GARCH models. The advantages
and drawbacks of each procedure are outlined as well as the advantages of the
Bayesian approach versus classical procedures. The paper makes emphasis on
recent Bayesian non-parametric approaches for GARCH models that avoid imposing
arbitrary parametric distributional assumptions. These novel approaches
implicitly assume infinite mixture of Gaussian distributions on the
standardized returns which have been shown to be more flexible and describe
better the uncertainty about future volatilities. Finally, the survey presents
an illustration using real data to show the flexibility and usefulness of the
non-parametric approach.


title:
Group analysis of generalized fifth-order Korteweg-de Vries equations
  with time-dependent coefficients

abstract:
  We perform enhanced Lie symmetry analysis of generalized fifth-order
Korteweg-de Vries equations with time-dependent coefficients. The corresponding
similarity reductions are classified and some exact solutions are constructed.


title: Chimera Death: Symmetry Breaking in Dynamical Networks

abstract:
  For a network of generic oscillators with nonlocal topology and
symmetry-breaking coupling we establish novel partially coherent inhomogeneous
spatial patterns, which combine the features of chimera states (coexisting
incongruous coherent and incoherent domains) and oscillation death (oscillation
suppression), which we call chimera death. We show that due to the interplay of
nonlocality and breaking of rotational symmetry by the coupling two distinct
scenarios from oscillatory behavior to a stationary state regime are possible:
a transition from an amplitude chimera to chimera death via in-phase
synchronized oscillations, and a direct abrupt transition for larger coupling
strength.


title: Zero-error capacity of binary channels with memory

abstract:
  We begin a systematic study of the problem of the zero--error capacity of
noisy binary channels with memory and solve some of the non--trivial cases.


title: Gravitational Collapse In Vaidya Space-time For Galileon Gravity Theory

abstract:
  The motive of this work is to study gravitational collapse in Vaidya
space-time embedded in Galileon gravity theory. Galileon gravity is in fact an
infrared modification of Einstein gravity, which was proposed as a
generalization of the 4D effective theory in DGP brane model. Vaidya's metric
is used all over to follow the nature of future outgoing radial null geodesics.
Detecting whether the central singularity is naked or wrapped by an event
horizon, by the existence of future directed radial null geodesic emitted in
past from the singularity is the basic objective. To point out the existence of
positive trajectory tangent solution, both particular parametric cases (through
tabular forms) and wide range contouring process have been applied. Precisely,
the EoS in perfect fluid satisfies a wide range of phenomena: from dust to
exotic fluid like dark energy. We have used the EoS parameter $k$ to determine
the end collapse state in different cosmological era.


title: The Two Bell's Theorems of John Bell

abstract:
  Many of the heated arguments about the meaning of "Bell's theorem" arise
because this phrase can refer to two different theorems that John Bell proved,
the first in 1964 and the second in 1976. His 1964 theorem is the
incompatibility of quantum phenomena with the dual assumptions of locality and
determinism. His 1976 theorem is the incompatibility of quantum phenomena with
the unitary property of local causality. This is contrary to Bell's own later
assertions, that his 1964 theorem began with that single, and indivisible,
assumption of local causality (even if not by that name). While there are other
forms of Bell's theorems --- which I present to explain the relation between
Jarrett-completeness, "fragile locality", and EPR-completeness --- I maintain
that Bell's two versions are the essential ones. Although the two Bell's
theorems are logically equivalent, their assumptions are not, and the different
versions of the theorem suggest quite different conclusions, which are embraced
by different communities. For realists, the notion of local causality, ruled
out by Bell's 1976 theorem, is motivated implicitly by Reichenbach's Principle
of common cause and explicitly by the Principle of relativistic causality, and
it is the latter which must be forgone. Operationalists pay no heed to
Reichenbach's Principle, but wish to keep the Principle of relativistic
causality, which, bolstered by an implicit "Principle of agent-causation",
implies their notion of locality. Thus for operationalists, Bell's theorem is
the 1964 one, and implies that it is determinism that must be forgone. I
discuss why the two `camps' are drawn to these different conclusions, and what
can be done to increase mutual understanding.


title:
Hyperfine Interactions in MnAs studied by Perturbed Angular Correlations
  of $\gamma$-Rays using the probe $^{77}$Br$\rightarrow^{77}$Se and first
  principles calculations for MnAs and other Mn pnictides

abstract:
  The MnAs compound shows a first-order transition at T$_C\approx42$ C, and a
second-order transition at T$_t\approx120$ C. The first-order transition, with
structural (hexagonal-orthorhombic), magnetic (FM-PM) and electrical
conductivity changes, is associated to magnetocaloric, magnetoelastic, and
magnetoresistance effects. We report a study in a large temperature range from
$-196$ up to $140$ C, using the $\gamma-\gamma$ perturbed angular correlations
method with the radioactive probe $^{77}$Br$\rightarrow^{77}$Se, produced at
the ISOLDE-CERN facility. The electric field gradients and magnetic hyperfine
fields are determined across the first- and second-order phase transitions
encompassing the pure and mixed phase regimes in cooling and heating cycles.
The temperature irreversibility of the 1st order phase transition is seen
locally, at the nanoscopic scale sensitivity of the hyperfine field, by its
hysteresis, detailing and complementing information obtained with macroscopic
measurements (magnetization and X-ray powder diffraction). To interpret the
results, hyperfine parameters were obtained with first-principles
spin-polarized density functional calculations using the generalized gradient
approximation with the full potential (L)APW+lo method (\textsc{Wien2k} code)
by considering the Se probe at both Mn and As sites. A clear assignment of the
probe location at the As site is made and complemented with the calculated
densities of states and local magnetic moments. We model electronic and
magnetic properties of the chemically similar MnSb and MnBi compounds,
complementing previous calculations.


title: Strong Stationary Duality for M\"obius monotone Markov chains: examples

abstract:
  We construct strong stationary dual chains for Ising model on a circle,
non-symmetric random walk on square lattice and a random walk on hypercube. The
strong stationary dual chains are all sharp and have the same state space as
original chains. We use M\"obius monotonicity of these chains with respect to
natural orderings of the corresponding state spaces. This method provides an
easy way to find eigenvalues in the Ising model and for a random walk on
hypercube.
  Keywords: Markov chains; stochastic monotonicity; eigenvalues; M\"obius
monotonicity; strong stationary duality; strong stationary times; separation
distance; mixing time; Ising model; hypercube


title: Principles of Quantum Universe

abstract:
  The present monograph is devoted to the theory of gravitation derived
consequently as joint nonlinear realization of conformal and affine symmetries
by means of Cartan differential forms. In the framework of the joint nonlinear
realization of conformal and affine symmetries the interpretation of the last
cosmological observational data of Ia Supernovae, anisotropy of the primordial
radiation temperature and the mass spectrum of electroweak bosons, including
the Higgs particle mass in the expected region ~ 125 GeV, is given. All these
observational and experimental data testify to the vacuum energy dominance. The
vacuum Casimir energy is a source of intensive cosmological quantum creation
gravitons and electroweak bosons including Higgs particles from the empty
Universe during the first 10^(-12) sec. The products of decay of the
electroweak bosons give the matter content of the present day Universe,
including primordial radiation and its baryon asymmetry.


title: Quasi-droplet Microbubbles for High Resolution Sensing Applications

abstract:
  Optical properties and sensing capabilities of fused silica microbubbles were
studied numerically using a finite element method. Mode characteristics, such
as quality factor (Q) and effective refractive index, were determined for
different bubble diameters and shell thicknesses. For sensing applications with
whispering gallery modes (WGMs), thinner shells yield improved sensitivity.
However, the Q-factor decreases with reduced thickness and this limits the
final resolution. Three types of sensing applications with microbubbles, based
on their optimized geometrical parameters, were studied. Herein the so-called
quasi-droplet regime is defined and discussed. It is shown that best resolution
can be achieved when microbubbles act as quasi-droplets, even for water-filled
cavities at the telecommunications C-band.


title: Peak Solutions for the fractional Nirenberg problem

abstract:
  In this paper, the fractional order curvature equation $(-\Delta)^\gamma u =
(1 + \varepsilon K(x))u^{\frac{N + 2\gamma}{N - 2\gamma}}$ in $\mathbb{R}^N$ is
considered. Assuming $K(x)$ has two critical points satisfying certain local
conditions, we prove the existence of two-peak solutions.


title: On Tail Index Estimation based on Multivariate Data

abstract:
  This article is devoted to the study of tail index estimation based on i.i.d.
multivariate observations, drawn from a standard heavy-tailed distribution,
i.e. of which 1-d Pareto-like marginals share the same tail index. A
multivariate Central Limit Theorem for a random vector, whose components
correspond to (possibly dependent) Hill estimators of the common shape index
alpha, is established under mild conditions. Motivated by the statistical
analysis of extremal spatial data in particular, we introduce the concept of
(standard) heavy-tailed random field of tail index alpha and show how this
limit result can be used in order to build an estimator of alpha with small
asymptotic mean squared error, through a proper convex linear combination of
the coordinates. Beyond asymptotic results, simulation experiments illustrating
the relevance of the approach promoted are also presented.


title: Weak limits in non-linear conductivity

abstract:
  The problem of characterizing weak limits of sequences of solutions for a
non-linear diffusion equation of $p$-laplacian type is addressed. It is
formulated in terms of certain moments of underlying Young measures associated
with main fields corresponding to the non-linear equation. We show two main
results. One is a necessary condition; the other one a sufficient counterpart.
Unlike the linear case, those two conditions do not match.


title:
The Transition Matrix Element A_{gq}(N) of the Variable Flavor Number
  Scheme at O(\alpha_s^3)

abstract:
  We calculate the massive operator matrix element $A_{gq}^{(3)}(N)$ to 3-loop
order in Quantum Chromodynamics at general values of the Mellin variable $N$.
This is the first complete transition function needed in the variable flavor
number scheme obtained at $O(\alpha_s^3)$. A first independent recalculation is
performed for the contributions $\propto N_F$ of the 3-loop anomalous dimension
$\gamma_{gq}^{(2)}(N)$.


title: Local and Global Hartogs-Bochner Phenomenon in Tubes

abstract:
  A generalization of the Hartogs theorem is proved for a class of Tubes
structures. We assume that the intervening commutative Lie algebra admits at
least a number of globally solvable generators greater or equal to the
structure codimension. We give necessary and sufficient conditions for the
first cohomological group with compact support to be trivial. A such global
result was previously obtained only when the supporting manifold was the
Euclidean space. Further but canonical work is need to recover the Bochner
extension theorem.


title:
A comparative simulation study of data-driven methods for estimating
  density level sets

abstract:
  Density level sets are mainly estimated using one of three methodologies:
plug-in, excess mass, or a hybrid approach. The plug-in methods are based on
replacing the unknown density by some nonparametric estimator, usually the
kernel. Thus, the bandwidth selection is a fundamental problem from a practical
point of view. Recently, specific selectors for level sets have been proposed.
However, if some a priori information about the geometry of the level set is
available, then excess mass algorithms can be useful. In this case, a density
estimator is not necessary, and the problem of bandwidth selection can be
avoided. The third methodology is a hybrid of the others. As in the excess mass
method, it assumes a mild geometric restriction on the level set and, like the
plug-in approach, requires a pilot nonparametric estimator of the density. One
interesting open question concerns the practical performance of these methods.
In this work, existing methods are reviewed, and two new hybrid algorithms are
proposed. Their practical behaviour is compared through extensive simulations.


title:
A quantitative analysis of the effect of flexible loads on reserve
  markets

abstract:
  We propose and analyze a day-ahead reserve market model that handles bids
from flexible loads. This pool market model takes into account the fact that a
load modulation in one direction must usually be compensated later by a
modulation of the same magnitude in the opposite direction. Our analysis takes
into account the gaming possibilities of producers and retailers, controlling
load flexibility, in the day-ahead energy and reserve markets, and in imbalance
settlement. This analysis is carried out by an agent-based approach where, for
every round, each actor uses linear programs to maximize its profit according
to forecasts of the prices. The procurement of a reserve is assumed to be
determined, for each period, as a fixed percentage of the total consumption
cleared in the energy market for the same period. The results show that the
provision of reserves by flexible loads has a negligible impact on the energy
market prices but markedly decreases the cost of reserve procurement. However,
as the rate of flexible loads increases, the system operator has to rely more
and more on non-contracted reserves, which may cancel out the benefits made in
the procurement of reserves.