title:
Towards the event horizon -- the supermassive black hole in the Galactic
  Center

abstract:
  The center of our Galaxy hosts the best constrained supermassive black hole
in the universe, Sagittarius A* (Sgr A*). Its mass and distance have been
accurately determined from stellar orbits and proper motion studies,
respectively, and its high-frequency radio, and highly variable near-infrared
and X-ray emission originate from within a few Schwarzschild radii of the event
horizon. The theory of general relativity (GR) predicts the appearance of a
black hole shadow, which is a lensed image of the event horizon. This shadow
can be resolved by very long baseline radio interferometry and test basic
predictions of GR and alternatives thereof. In this paper we review our current
understanding of the physical properties of Sgr A*, with a particular emphasis
on the radio properties, the black hole shadow, and models for the emission and
appearance of the source. We argue that the Galactic Center holds enormous
potential for experimental tests of black hole accretion and theories of
gravitation in their strong limits.


title: Extremal Domains for Self-Commutators in the Bergman Space

abstract:
  In arXiv:1305.5193v1, the authors have shown that Putnam's inequality for the
norm of self-commutators can be improved by a factor of $\frac{1}{2}$ for
Toeplitz operators with analytic symbol $\varphi$ acting on the Bergman space
$A^{2}(\Omega)$. This improved upper bound is sharp when $\varphi(\Omega)$ is a
disk. In this paper we show that disks are the only domains for which the upper
bound is attained.


title:
Nuclear Structure Uncertainties in Parity-Violating Electron Scattering
  from Carbon 12

abstract:
  High precision measurements of the parity-violating asymmetry in polarized
electron scattering from nuclei can be used to extract information on nuclear
and nucleon structure or to determine Standard Model couplings and higher-order
radiative corrections. To this end, low uncertainties are also required in the
effects that inevitably arise from modeling the underlying nuclear structure.
An experimental precision of a few tenths of a percent may be attainable for
the asymmetry if the appropriate kinematic range is chosen, as will be
discussed here for the case of $^{12}$C. And given this, the dual goal of
ascertaining both the sizes of various nuclear structure related effects and of
providing estimates of their uncertainties for this particular target will be
discussed.


title: Tolman IV solution in the Randall-Sundrum Braneworld

abstract:
  In the context of the Randall-Sundrum braneworld, the minimal geometric
deformation approach (MGD) is used to generate an exact analytic interior
solution to four-dimensional effective Einstein's field equations for a
spherically symmetric compact distribution. This solution represents the
braneworld version of the well known Tolman IV solution in General Relativity.
By using this analytic solution, an exhaustive analysis of the braneworld
effects on realistic stellar interiors is developed, finding strong evidences
in favor of the hypothesis that compactness is reduced due to bulk effects on
stellar configurations.


title: Non abelian hydrodynamics and heavy ion collisions

abstract:
  The goal of the relativistic heavy ion collisions (RHIC) program is to create
a state of matter where color degrees of freedom are deconfined. The dynamics
of matter in this state, in spite of the complexities of quantum
chromodynamics, is largely determined by the conservation laws of energy
momentum and color currents. Therefore it is possible to describe its main
features in hydrodynamic terms, the very short color neutralization time
notwithstanding. In this lecture we shall give a simple derivation of the
hydrodynamics of a color charged fluid, by generalizing the usual derivation of
hydrodynamics from kinetic theory to the non abelian case.


title: Demonstration of long-lived high power optical waveguides in air

abstract:
  We demonstrate that femtosecond filaments can set up an extended and robust
thermal waveguide structure in air with a lifetime of several milliseconds,
making possible the very long range guiding and distant projection of high
energy laser pulses and high average power beams. As a proof of principle, we
demonstrate guiding of 110 mJ, 7 ns, 532 nm pulses with 90% throughput over ~15
Rayleigh lengths in a 70 cm long air waveguide generated by the long timescale
thermal relaxation of an array of femtosecond filaments. The guided pulse was
limited only by our available laser energy. In general, these waveguides should
be robust against the effects of thermal blooming of extremely high average
power laser beams.


title:
Search for Natural SUSY with inclusive search strategies at the LHC
  using the CMS detector

abstract:
  Natural SUSY suggests the existence of light stop quarks, accessible at the
LHC, which are the focus of a dedicated CMS search program. I present two
inclusive CMS searches that look for TeV scale colored sparticles in final
states with jets, b-tagged jets and missing transverse energy performed using
up to 19.4fb-1 of 8TeV LHC proton-proton data. No deviation from the Standard
Model was observed in these searches, and the implications for this was shown
for several simplified model scenarios and phenomenological MSSM.


title: On the admissibility of certain local system

abstract:
  A rank one local system on the complement of a hyperplane arrangement is said
to be admissible if it satisfies certain non-positivity condition at every
resonant edges. It is known that the cohomology of admissible local system can
be computed combinatorially. In this paper, we study the structure of the set
of all non-admissible local systems in the character torus. We prove that the
set of non-admissible local systems forms a union of subtori. The relations
with characteristic varieties are also discussed.


title: Hydrodynamics at RHIC and LHC: What have we learned?

abstract:
  Fluid dynamical description of elementary particle collisions has a long
history dating back to the works of Landau and Fermi. Nevertheless, it is
during the last 10-15 years when fluid dynamics has become the standard tool to
describe the evolution of matter created in ultrarelativistic heavy ion
collisions. In this review I briefly describe the hydrodynamical models, what
we have learned when analyzing the RHIC and LHC data using these models, and
what the latest developments and challenges are.


title: Impacts of demographic catastrophes

abstract:
  Analysis of demographic catastrophes shows that, with the exception of
perhaps only two critical events, they were too weak to influence the growth of
human population. These results reinforce the conclusion that the concept of
the Epoch of Malthusian Stagnation, the alleged first stage of growth claimed
by the Demographic Transition Theory, is not supported by empirical evidence.
They show that even if we assume that Malthusian positive checks are capable of
suppressing the growth of population their impact was too weak to create the
Epoch of Malthusian Stagnation.


title:
Efficient Quantum Algorithms for Analyzing Large Sparse Electrical
  Networks

abstract:
  Analyzing large sparse electrical networks is a fundamental task in physics,
electrical engineering and computer science. We propose two classes of quantum
algorithms for this task. The first class is based on solving linear systems,
and the second class is based on using quantum walks. These algorithms compute
various electrical quantities, including voltages, currents, dissipated powers
and effective resistances, in time $\operatorname{poly}(d, c,
\operatorname{log}(N), 1/\lambda, 1/\epsilon)$, where $N$ is the number of
vertices in the network, $d$ is the maximum unweighted degree of the vertices,
$c$ is the ratio of largest to smallest edge resistance, $\lambda$ is the
spectral gap of the normalized Laplacian of the network, and $\epsilon$ is the
accuracy. Furthermore, we show that the polynomial dependence on $1/\lambda$ is
necessary. This implies that our algorithms are optimal up to polynomial
factors and cannot be significantly improved.


title: Concrete Categories in Homotopy Type Theory

abstract:
  We introduce some classes of genuine higher categories in homotopy type
theory, defined as well-behaved subcategories of the category of types. We give
several examples, and some techniques for showing other things are not
examples. While only a small part of what is needed, it is a natural
construction, and may be instructive for people seeking to provide a fully
general construction.


title: Topologically Massive Yang-Mills Theory and Link Invariants

abstract:
  Topologically massive Yang-Mills theory is studied in the framework of
geometric quantization. Since this theory has a mass gap proportional to the
topological mass m, Yang-Mills contribution decays exponentially at very large
distances compared to 1/m, leaving a pure Chern-Simons theory with level number
k. In this paper, the near Chern-Simons limit is studied where the distance is
large enough to give an almost topological theory, with a small contribution
from the Yang-Mills term. It is shown that this almost topological theory
consists of two copies of Chern-Simons with level number k/2, very similar to
the Chern-Simons splitting of topologically massive AdS gravity. Also, gauge
invariance of these half-Chern-Simons theories is discussed. As m approaches to
infinity, the split parts add up to give the original Chern-Simons term with
level k. Reduction of the phase space is discussed in this limit. Finally, a
relation between the observables of topologically massive Yang-Mills theory and
Chern-Simons theory is shown. One of the two split Chern-Simons pieces is shown
to be associated with Wilson loops while the other with 't Hooft loops. This
allows one to use skein relations to calculate topologically massive Yang-Mills
theory observables in the near Chern-Simons limit.


title: A note on morphisms determined by objects

abstract:
  We prove that a Hom-finite additive category having determined morphisms on
both sides is a dualizing variety. This complements a result by Krause. We
prove that in a Hom-finite abelian category having Serre duality, a morphism is
right determined by some object if and only if it is an epimorphism. We give a
characterization to abelian categories having Serre duality via determined
morphisms.


title: A 30 mK, 13.5 T scanning tunneling microscope with two independent tips

abstract:
  We describe the design, construction, and performance of an ultra-low
temperature, high-field scanning tunneling microscope (STM) with two
independent tips. The STM is mounted on a dilution refrigerator and operates at
a base temperature of 30 mK with magnetic fields of up to 13.5 T. We focus on
the design of the two-tip STM head, as well as the sample transfer mechanism,
which allows \textit{in situ} transfer from an ultra high vacuum (UHV)
preparation chamber while the STM is at 1.5 K. Other design details such as the
vibration isolation and rf-filtered wiring are also described. Their
effectiveness is demonstrated via spectral current noise characteristics and
the root mean square roughness of atomic resolution images. The high-field
capability is shown by the magnetic field dependence of the superconducting gap
of $\text{Cu}_x\text{Bi}_2\text{Se}_3$. Finally, we present images and
spectroscopy taken with superconducting Nb tips with the refrigerator at 35 mK
that indicate that the effective temperature of our tips/sample is
approximately 184 mK, corresponding to an energy resolution of 16 $\mu$eV.


title: Submodularization for Quadratic Pseudo-Boolean Optimization

abstract:
  Many computer vision problems require optimization of binary non-submodular
energies. We propose a general optimization framework based on local submodular
approximations (LSA). Unlike standard LP relaxation methods that linearize the
whole energy globally, our approach iteratively approximates the energies
locally. On the other hand, unlike standard local optimization methods (e.g.
gradient descent or projection techniques) we use non-linear submodular
approximations and optimize them without leaving the domain of integer
solutions. We discuss two specific LSA algorithms based on "trust region" and
"auxiliary function" principles, LSA-TR and LSA-AUX. These methods obtain
state-of-the-art results on a wide range of applications outperforming many
standard techniques such as LBP, QPBO, and TRWS. While our paper is focused on
pairwise energies, our ideas extend to higher-order problems. The code is
available online (http://vision.csd.uwo.ca/code/).


title: General relativistic density perturbations

abstract:
  We investigate a general relativistic mechanism in which spikes generate
matter overdensities in the early universe. When the cosmological fluid is
tilted, the tilt provides another mechanism in generating matter
inhomogeneities. We numerically investigate the effect of a sign change in the
tilt, when there is a spike but the tilt does not change sign, and when the
spike and the sign change in the tilt coincide. We find that the tilt plays the
primary role in generating matter inhomogeneities, and it does so by creating
both local overdensities and underdensities. We discuss of the physical
implications of the work.


title:
Theory of a Directive Optical Leaky Wave Antenna Integrated into a
  Resonator and Enhancement of Radiation Control

abstract:
  We provide for the first time the detailed study of the radiation performance
of an optical leaky wave antenna (OLWA) integrated into a Fabry-P\'erot
resonator. We show that the radiation pattern can be expressed as the one
generated by the interference of two leaky waves counter-propagating in the
resonator leading to a design procedure for achieving optimized broadside
radiation, i.e., normal to the waveguide axis. We thus report a realizable
implementation of the OLWA made of semiconductor and dielectric regions. The
theoretical modeling is supported by full-wave simulation results, which are
found to be in good agreement. We aim to control the radiation intensity in the
broadside direction via excess carrier generation in the semiconductor regions.
We show that the presence of the resonator can provide an effective way of
enhancing the radiation level modulation, which reaches values as high as 13.5
dB, paving the way for novel promising control capabilities that might allow
the generation of very fast optical switches, as an example.


title:
Simple DFS on the Complement of a Graph and on Partially Complemented
  Digraphs

abstract:
  A complementation operation on a vertex of a digraph changes all outgoing
arcs into non-arcs, and outgoing non-arcs into arcs. A partially complemented
digraph $\widetilde{G}$ is a digraph obtained from a sequence of vertex
complement operations on $G$. Dahlhaus et al. showed that, given an
adjacency-list representation of $\widetilde{G}$, depth-first search (DFS) on
$G$ can be performed in $O(n + \widetilde{m})$ time, where $n$ is the number of
vertices and $\widetilde{m}$ is the number of edges in $\widetilde{G}$. To
achieve this bound, their algorithm makes use of a somewhat complicated
stack-like data structure to simulate the recursion stack, instead of
implementing it directly as a recursive algorithm. We give a recursive
$O(n+\widetilde{m})$ algorithm that uses no complicated data-structures.


title: Modeling of Atmospheric Flow Around a Coastal Cape: Lee Side Story

abstract:
  The current research focuses on mesoscale dynamics of the atmospheric
circulation around an idealized coastal cape representing typical summertime
circulation along the northwest coast of the U.S., studied using a mesoscale
coupled ocean-atmosphere modeling system. The orographic wind maximum features
a strong NW flow extending a few hundred kilometers downstream and seaward of
the cape, which closely follows mesoscale orographic low pressure developed in
the lee of the cape. Both wind maximum and the lee trough experience a
pronounced diurnal cycle, marked by maximum northwest flow and minimum pressure
in the local evening hours (its opposite phase during morning hours), and
confirmed by observations from limited buoy and coastal stations.
  Vertical structure of the atmospheric boundary layer over the coastal ocean
on the lee side of the cape indicated the downward propagation of potential
temperature and wind features during the course of the day, as opposed to the
traditional surface-driven development of the atmospheric boundary layer.
Momentum analysis showed the local pressure gradients near the surface vary
greatly depending on the relative location about the cape. Strong perturbations
in relative vorticity downwind of the cape supported the hypothesis that
mountain dynamics have a key role in establishing wind regime around the cape.
The sensitivity studies indicated the importance of coastal terrain elevation
on the formation and the strength of the lee trough and wind maximum. Higher
coastal topography was found to cause greater separation of the upwelling front
(jet) from the coast downwind of the cape.


title: A stochastic microscopic model for the dynamics of antigenic variation

abstract:
  We present a novel model that describes the within-host evolutionary dynamics
of parasites undergoing antigenic variation. The approach uses a multi-type
branching process with two types of entities defined according to their
relationship with the immune system: clans of resistant parasitic cells (i.e.
groups of cells sharing the same antigen not yet recognized by the immune
system) that may become sensitive, and individual sensitive cells that can
acquire a new resistance thus giving rise to the emergence of a new clan. The
simplicity of the model allows analytical treatment to determine the
subcritical and supercritical regimes in the space of parameters. By
incorporating a density-dependent mechanism the model is able to capture
additional relevant features observed in experimental data, such as the
characteristic parasitemia waves. In summary our approach provides a new
general framework to address the dynamics of antigenic variation which can be
easily adapted to cope with broader and more complex situations.


title:
A Polarization-insensitive and high-efficiency Schottky Photodetector
  integrated with a silicon ridge waveguide

abstract:
  We propose a polarization-insensitive and high-efficiency plasmonic silicon
Schottky diode for detection of sub-bandgap photons in the optical
communication wavelength range through internal photoemission. Our photodiode
is based on a hybrid plasmonic silicon waveguide. It has a gold film covering
both the top and the sidewalls of a dielectric silicon waveguide with the
Schottky contact formed at the gold-silicon interface. An extensive physical
model is presented in detail and applied to calculate and analyze the
performance of our detector. By comparison with a diode with only top contact
of gold, the polarization sensitivity of responsivity is greatly minimized in
our photodetector with sidewall coverage of gold. Much higher responsivities
for both polarizations are also achieved in a very broad wavelength range of
1.2-1.5 {\mu}m. Moreover, the Schottky contact is only 4 {\mu}m long, leading
to a very small dark current. Our design is very promising for practical
applications in high-density silicon photonic integration.


title: An invariant of rational homology 3-spheres via vector fields

abstract:
  We define an invariant of rational homology 3-spheres via vector fields. The
construction of our invariant is a generalization of both that of the
Kontsevich-Kuperberg-Thurston invariant and that of Watanabe's Morse homotopy
invariant, which implies the equivalence of these two invariants.


title: Entropy Production in Simple Special Relativistic Fluids

abstract:
  It is well known that, in the absence of external forces, simple
non-relativistic fluids involve entropy production only through heat conduction
and shear viscosity. In this work, it is shown that a number density gradient
contributes to the local entropy production of a simple relativistic fluid
using special relativistic kinetic theory. Also, the presence of an external
field may cause strictly relativistic contributions to the entropy production,
a fact not widely recognized. The implications of these effects are thoroughly
discussed.


title:
The decomposability problem for torsion-free abelian groups is analytic
  complete

abstract:
  We discuss the decomposability of torsion-free abelian groups. We show that
among computable groups of finite rank this property is $\Sigma^0_3$-complete.
However, when we consider groups of infinite rank, it becomes
$\Sigma^1_1$-complete, so it cannot be characterized by a first-order formula
in the language of arithmetic.


title:
Single Spin Asymmetries of Inclusive Hadrons Produced in Electron
  Scattering from a Transversely Polarized $^3$He Target

abstract:
  We report the first measurement of target single-spin asymmetries (A$_N$) in
the inclusive hadron production reaction,
$e~$+$~^3\text{He}^{\uparrow}\rightarrow h+X$, using a transversely polarized
$^3$He target. The experiment was conducted at Jefferson Lab in Hall A using a
5.9-GeV electron beam. Three types of hadrons ($\pi^{\pm}$, $\text{K}^{\pm}$
and proton) were detected in the transverse hadron momentum range 0.54 $<p_T<$
0.74 GeV/c. The range of $x_F$ for pions was -0.29 $<x_F<$ -0.23 and for kaons
-0.25 $<x_F<$-0.18. The observed asymmetry strongly depends on the type of
hadron. A positive asymmetry is observed for $\pi^+$ and $\text{K}^+$. A
negative asymmetry is observed for $\pi^{-}$. The magnitudes of the asymmetries
follow $|A^{\pi^-}| < |A^{\pi^+}| < |A^{K^+}|$. The K$^{-}$ and proton
asymmetries are consistent with zero within the experimental uncertainties. The
$\pi^{+}$ and $\pi^{-}$ asymmetries measured for the $^3$He target and
extracted for neutrons are opposite in sign with a small increase observed as a
function of $p_T$.


title:
A New Discontinuous Galerkin Finite Element Method for Directly Solving
  the Hamilton-Jacobi Equations

abstract:
  In this paper, we improve upon the discontinuous Galerkin (DG) method for
Hamilton-Jacobi (HJ) equation with convex Hamiltonians in (Y. Cheng and C.-W.
Shu, J. Comput. Phys. 223:398-415,2007) and develop a new DG method for
directly solving the general HJ equations. The new method avoids the
reconstruction of the solution across elements by utilizing the Roe speed at
the cell interface. Besides, we propose an entropy fix by adding penalty terms
proportional to the jump of the normal derivative of the numerical solution.
The particular form of the entropy fix was inspired by the Harten and Hyman's
entropy fix (A. Harten and J. M. Hyman. J. Comput. Phys. 50(2):235-269, 1983)
for Roe scheme for the conservation laws. The resulting scheme is compact,
simple to implement even on unstructured meshes, and is demonstrated to work
for nonconvex Hamiltonians. Benchmark numerical experiments in one dimension
and two dimensions are provided to validate the performance of the method.


title: Quantum affine $\frak{gl}_n$ via Hecke algebras

abstract:
  We use the Hecke algebras of affine symmetric groups and their associated
Schur algebras to construct a new algebra through a basis, and a set of
generators and explicit multiplication formulas of basis elements by
generators. We prove that this algebra is isomorphic to the quantum enveloping
algebra of the loop algebra of $\mathfrak {gl}_n$. Though this construction is
motivated by the work \cite{BLM} by Beilinson--Lusztig--MacPherson for quantum
$\frak{gl}_n$, our approach is purely algebraic and combinatorial, independent
of the geometric method which seems to work only for quantum $\mathfrak{gl}_n$
and quantum affine $\mathfrak{sl}_n$. As an application, we discover a
presentation of the Ringel--Hall algebra of a cyclic quiver by semisimple
generators and their multiplications by the defining basis elements.


title: Optimization, Learning, and Games with Predictable Sequences

abstract:
  We provide several applications of Optimistic Mirror Descent, an online
learning algorithm based on the idea of predictable sequences. First, we
recover the Mirror Prox algorithm for offline optimization, prove an extension
to Holder-smooth functions, and apply the results to saddle-point type
problems. Next, we prove that a version of Optimistic Mirror Descent (which has
a close relation to the Exponential Weights algorithm) can be used by two
strongly-uncoupled players in a finite zero-sum matrix game to converge to the
minimax equilibrium at the rate of O((log T)/T). This addresses a question of
Daskalakis et al 2011. Further, we consider a partial information version of
the problem. We then apply the results to convex programming and exhibit a
simple algorithm for the approximate Max Flow problem.


title:
Mapping of the Influenza-A Hemagglutinin Serotypes Evolution by the
  ISSCOR Method

abstract:
  Analyses and visualizations by the ISSCOR method of influenza virus
hemagglutinin genes of different A-subtypes revealed some rather striking
temporal relationships between groups of individual gene subsets. Based on
these findings we consider application of the ISSCOR-PCA method for analyses of
large sets of homologous genes to be a worthwhile addition to a toolbox of
genomics - allowing for a rapid diagnostics of trends, and ultimately even
aiding an early warning of newly emerging epidemiological threats.


title:
Harmonic analysis on homogeneous complex bounded domains and
  noncommutative geometry

abstract:
  We define and study a noncommutative Fourier transform on every homogeneous
complex bounded domain. We then give an application in noncommutative
differential geometry by defining noncommutative Baumslag-Solitar tori.


title: Optimality Conditions in Vector Optimization

abstract:
  In this paper we obtain second- and first-order optimality conditions of
Kuhn-Tucker type and Fritz John one for weak efficiency in the vector problem
with inequality constraints. In the necessary conditions we suppose that the
objective function and the active constraints are continuously differentiable.
We introduce notions of KTSP-invex problem and second-order KTSP-invex one. We
obtain that the vector problem is (second-order) KTSP-invex if and only if for
every triple $(\bar x,\bar\lambda,\bar\mu)$ with Lagrange multipliers
$\bar\lambda$ and $\bar\mu$ for the objective function and constraints
respectively, which satisfies the (second-order) necessary optimality
conditions, the pair $(\bar x,\bar\mu)$ is a saddle point of the scalar
Lagrange function with a fixed multiplier $\bar\lambda$. We introduce notions
second-order KT-pseudoinvex-I, second-order KT-pseudo\-invex-II, second-order
KT-invex problems. We prove that every second-order Kuhn-Tucker stationary
point is a weak global Pareto minimizer (global Pareto minimizer) if and only
if the problem is second-order KT-pseudoinvex-I (KT-pseudoinvex-II). It is
derived that every second-order Kuhn Tucker stationary point is a global
solution of the weighting problem if and only if the vector problem is
second-order KT-invex.


title: An Asynchronous Parallel Stochastic Coordinate Descent Algorithm

abstract:
  We describe an asynchronous parallel stochastic coordinate descent algorithm
for minimizing smooth unconstrained or separably constrained functions. The
method achieves a linear convergence rate on functions that satisfy an
essential strong convexity property and a sublinear rate ($1/K$) on general
convex functions. Near-linear speedup on a multicore system can be expected if
the number of processors is $O(n^{1/2})$ in unconstrained optimization and
$O(n^{1/4})$ in the separable-constrained case, where $n$ is the number of
variables. We describe results from implementation on 40-core processors.


title:
Estimates on the Growth of Meromorphic Solutions of Linear Differential
  Equations with density conditions

abstract:
  We give an alternative and simpler method for getting pointwise estimate of
meromorphic solutions of homogeneous linear differential equations with
coefficients meromorphic in a finite disk or in the open plane originally
obtained by Hayman and the author. In particular, our estimates generally give
better upper bounds for higher order derivatives of the meromorphic solutions
under consideration, are valid, however, outside an exceptional set of finite
logarithmic density.
  The estimates again show that the growth of meromorphic solutions with a
positive deficiency at infinity can be estimated in terms of initial conditions
of the solution at or near the origin and the characteristic functions of the
coefficients.


title:
Large Negative Quantum Renormalization of Excitation Energies in the
  Spin-1/2 Kagome Lattice Antiferromagnet Cs$_2$Cu$_3$SnF$_{12}$

abstract:
  Magnetic excitations in the spin-$\frac{1}{2}$ distorted kagome lattice
antiferromagnet Cs$_2$Cu$_3$SnF$_{12}$, which has an ordered ground state owing
to the strong Dzyaloshinskii-Moriya interaction, were studied using inelastic
neutron scattering. Although the spin-wave dispersion can be qualitatively
understood in terms of linear spin-wave theory (LSWT), the excitation energies
are renormalized by a factor of approximately 0.6 from those calculated by
LSWT, almost irrespective of the momentum transfer. This inadequacy of LSWT,
which is attributed to quantum fluctuations, provides evidence of negative
quantum renormalization in the spin-$\frac{1}{2}$ kagome lattice
antiferromagnet.


title:
Mean Field Linear-Quadratic-Gaussian (LQG) Games of Forward-Backward
  Stochastic Differential Equations

abstract:
  This paper studies a new class of dynamic optimization problems of
large-population (LP) system which consists of a large number of negligible and
coupled agents. The most significant feature in our setup is the dynamics of
individual agents follow the forward-backward stochastic differential equations
(FBSDEs) in which the forward and backward states are coupled at the terminal
time. This current paper is hence different to most existing large-population
literature where the individual states are typically modeled by the SDEs
including the forward state only. The associated mean-field
linear-quadratic-Gaussian (LQG) game, in its forward-backward sense, is also
formulated to seek the decentralized strategies. Unlike the forward case, the
consistency conditions of our forward-backward mean-field games involve six
Riccati and force rate equations. Moreover, their initial and terminal
conditions are mixed thus some special decoupling technique is applied here. We
also verify the $\epsilon$-Nash equilibrium property of the derived
decentralized strategies. To this end, some estimates to backward stochastic
system are employed. In addition, due to the adaptiveness requirement to
forward-backward system, our arguments here are not parallel to those in its
forward case.


title:
The first, second and fourth Painlev\'{e} equations on weighted
  projective spaces

abstract:
  The first, second and fourth Painlev\'{e} equations are studied by means of
dynamical systems theory and three dimensional weighted projective spaces $\C
P^3(p,q,r,s)$ with suitable weights $(p,q,r,s)$ determined by the Newton
diagrams of the equations or the versal deformations of vector fields. Singular
normal forms of the equations, a simple proof of the Painlev\'{e} property and
symplectic atlases of the spaces of initial conditions are given with the aid
of the orbifold structure of $\C P^3(p,q,r,s)$. In particular, for the first
Painlev\'{e} equation, a well known Painlev\'{e}'s transformation is
geometrically derived, which proves to be the Darboux coordinates of a certain
algebraic surface with a holomorphic symplectic form. The affine Weyl group,
Dynkin diagram and the Boutroux coordinates are also studied from a view point
of the weighted projective space.


title:
The ground state and the character of the interaction between a
  colloidal particles in a liquid crystals

abstract:
  In this article is proposed the general approach to determination the
character of the interaction between colloidal particles in a different liquid
crystals. The main idea of this approach are in the presentation of the
colloidal particle as sours of the possible deformation of the ground state of
the director field. The ground state of liquid crystal imposes restrictions on
the possible deformations and as result determine the character of the
interaction between the colloidal particles. Based on this approach the Coulomb
like interaction between dipole particles in a cholesteric liquid crystal and
changing of the character of the interaction in a smactic liquid crystal has
been predicted.


title:
B-Machine Polarimeter: A Telescope to Measure the Polarization of the
  Cosmic Microwave Background

abstract:
  The B-Machine Telescope is the culmination of several years of development,
construction, characterization and observation. The telescope is a departure
from standard polarization chopping of correlation receivers to a half wave
plate technique. Typical polarimeters use a correlation receiver to chop the
polarization signal to overcome the $1/f$ noise inherent in HEMT amplifiers.
B-Machine uses a room temperature half wave plate technology to chop between
polarization states and measure the polarization signature of the CMB. The
telescope has a demodulated $1/f$ knee of 5 mHz and an average sensitivity of
1.6 $\mathrm{mK}\sqrt{\mathrm{s}}$. This document examines the construction,
characterization, observation of astronomical sources, and data set analysis of
B-Machine. Preliminary power spectra and sky maps with large sky coverage for
the first year data set are included.


title:
Spectral Formulation of the Elastodynamic Boundary Integral Equations
  for Bi-material Interfaces

abstract:
  A spectral formulation of the plane-strain boundary integral equations for an
interface between dissimilar elastic solids is presented. The boundary integral
equations can be written in two equivalent forms: (a) The tractions can be
written as a space-time convolution of the displacement continuities at the
interface (Budiansky and Rice, 1979) (b) The displacement discontinuities can
be written as a space-time convolution of the tractions at the interface
(Kostrov, 1966). Prior work on spectral formulation of the boundary integral
equations has adopted the former as the starting point. The present work has
for its basis the latter form based on a space-time convolution of the
tractions. Tractions and displacement components are given a spectral
representation in the spatial coordinate along the interface. The radiation
damping term is then explicitly extracted to avoid singularities in the
convolution kernels. With the spectral forms introduced, the space-time
convolutions reduce to convolutions in time for each Fourier mode. Due to
continuity of tractions at the interface, this leads to a simpler formulation
and form of the convolution kernels in comparison to the formulation involving
convolutions over the slip and opening history at the bi-material interface.
The convolution kernels are validated by studying some model problems to which
analytical solutions are known. When coupled with a cohesive law or a friction
law at the interface, the formulation proposed here is of wide applicability
for studying spontaneous rupture propagation.


title: Spin wave nonreciprocity for logic device applications

abstract:
  The utilization of spin waves as eigenmodes of the magnetization dynamics for
information processing and communication has been widely explored recently due
to its high operational speed with low power consumption and possible
applications for quantum computations. Previous proposals of spin wave
Mach-Zehnder devices were based on the spin wave phase, a delicate entity which
can be easily disrupted. Here, we propose a complete logic system based on the
spin wave amplitude utilizing the nonreciprocal spin wave behavior excited by
microstrip antennas. The experimental data reveal that the nonreciprocity of
magnetostatic surface spin wave can be tuned by the bias magnetic field.
Furthermore, engineering of the device structure could result in a high
nonreciprocity factor for spin wave logic applications.


title: The complex singularity of a Stokes wave

abstract:
  Two-dimensional potential flow of the ideal incompressible fluid with free
surface and infinite depth can be described by a conformal map of the fluid
domain into the complex lower half-plane. Stokes wave is the fully nonlinear
gravity wave propagating with the constant velocity. The increase of the scaled
wave height $H/\lambda$ from the linear limit $H/\lambda=0$ to the critical
value $H_{max}/\lambda$ marks the transition from the limit of almost linear
wave to a strongly nonlinear limiting Stokes wave. Here $H$ is the wave height
and $\lambda$ is the wavelength. We simulated fully nonlinear Euler equations,
reformulated in terms of conformal variables, to find Stokes waves for
different wave heights. Analyzing spectra of these solutions we found in
conformal variables, at each Stokes wave height, the distance $v_c$ from the
lowest singularity in the upper half-plane to the real line which corresponds
to the fluid free surface. We also identified that this singularity is the
square-root branch point. The limiting Stokes wave emerges as the singularity
reaches the fluid surface. From the analysis of data for $v_c\to 0$ we suggest
a new power law scaling $v_c\propto (H_{max}-H)^{3/2}$ as well as new estimate
$H_{max}/\lambda \simeq 0.1410633$.

categories: physics.flu-dyn nlin.PS physics.ao-ph physics.comp-ph


title: Twist Accumulation and Topology Structure of a Solar Magnetic Flux Rope

abstract:
  To study the build up of a magnetic flux rope before a major flare and
coronal mass ejection (CME), we compute the magnetic helicity injection, twist
accumulation, and the topology structure of the three dimensional magnetic
field, which is derived by the nonlinear force-free field model. The
Extreme-ultraviolet Imaging Telescope on board the Solar and Heliospheric
Observatory observed a series of confined flares without any CME before a major
flare with a CME at 23:02 UT on 2005 January 15 in active region NOAA 10720. We
derive the vector velocity at eight time points from 18:27 UT to 22:20 UT with
the differential affine velocity estimator for vector magnetic fields, which
were observed by the Digital Vector Magnetograph at Big Bear Solar Observatory.
The injected magnetic helicity is computed with the vector magnetic and
velocity fields. The helicity injection rate was (-16.47 \pm 3.52) \times
10^{40} Mx^2/hr. We find that only about 1.8% of the injected magnetic helicity
became finally the internal helicity of the magnetic flux rope, whose twist
increasing rate was -0.18 \pm 0.08 Turns/hr. The quasi-separatrix layers (QSLs)
of the three dimensional magnetic field are computed by evaluating the
squashing degree, Q. We find that the flux rope was wrapped by QSLs with large
Q values, where the magnetic reconnection induced by the continuously injected
magnetic helicity further produced the confined flares. We suggest that the
flux rope was built up and heated by the magnetic reconnection in the QSLs.


title:
A Parallel Simulated Annealing Approach for the Mirrored Traveling
  Tournament Problem

abstract:
  The Traveling Tournament Problem (TTP) is a benchmark problem in sports
scheduling and has been extensively studied in recent years. The Mirrored
Traveling Tournament Problem (mTTP) is variation of the TTP that represents
certain types of sports scheduling problems where the main objective is to
minimize the total distance traveled by all the participating teams. In this
paper we test a parallel simulated annealing approach for solving the mTTP
using OpenMP on shared memory systems and we found that this approach is
superior especially with respect to the number of solution instances that are
probed per second. We also see that there is significant speed up of 1.5x -
2.2x in terms of number of solutions explored per unit time.


title: Verifiable Control System Development for Gas Turbine Engines

abstract:
  A control software verification framework for gas turbine engines is
developed. A stability proof is presented for gain scheduled closed-loop engine
system based on global linearization and linear matrix inequality (LMI)
techniques. Using convex optimization tools, a single quadratic Lyapunov
function is computed for multiple linearizations near equilibrium points of the
closed-loop system. With the computed stability matrices, ellipsoid invariant
sets are constructed, which are used efficiently for DGEN turbofan engine
control code stability analysis. Then a verifiable linear gain scheduled
controller for DGEN engine is developed based on formal methods, and tested on
the engine virtual test bench. Simulation results show that the developed
verifiable gain scheduled controller is capable of regulating the engine in a
stable fashion with proper tracking performance.


title: Thermodynamic and Logical Reversibilities Revisited

abstract:
  We review and investigate the general theory of thermodynamics of
computation, and derive the fundamental inequalities that set the lower bounds
of the work requirement and the heat emission during a computation. These
inequalities constitute the generalized Landauer principle, where the
information contents are involved in the second law of thermodynamics. We
discuss in detail the relationship between the thermodynamic and logical
reversibilities; the former is related to the entropy production in the total
system including a heat bath, while the latter is related to the entropy change
only in the logical states of the memory. In particular, we clarify that any
logically irreversible computation can be performed in a thermodynamically
reversible manner in the quasi-static limit, which does not contradict the
conventional Landauer principle. Our arguments would serve as the theoretical
foundation of thermodynamics of computation in terms of modern statistical
physics.


title: Demand Side Management in Smart Grids using a Repeated Game Framework

abstract:
  Demand side management (DSM) is a key solution for reducing the peak-time
power consumption in smart grids. To provide incentives for consumers to shift
their consumption to off-peak times, the utility company charges consumers
differential pricing for using power at different times of the day. Consumers
take into account these differential prices when deciding when and how much
power to consume daily. Importantly, while consumers enjoy lower billing costs
when shifting their power usage to off-peak times, they also incur discomfort
costs due to the altering of their power consumption patterns. Existing works
propose stationary strategies for the myopic consumers to minimize their
short-term billing and discomfort costs. In contrast, we model the interaction
emerging among self-interested, foresighted consumers as a repeated energy
scheduling game and prove that the stationary strategies are suboptimal in
terms of long-term total billing and discomfort costs. Subsequently, we propose
a novel framework for determining optimal nonstationary DSM strategies, in
which consumers can choose different daily power consumption patterns depending
on their preferences, routines, and needs. As a direct consequence of the
nonstationary DSM policy, different subsets of consumers are allowed to use
power in peak times at a low price. The subset of consumers that are selected
daily to have their joint discomfort and billing costs minimized is determined
based on the consumers' power consumption preferences as well as on the past
history of which consumers have shifted their usage previously. Importantly, we
show that the proposed strategies are incentive-compatible. Simulations confirm
that, given the same peak-to-average ratio, the proposed strategy can reduce
the total cost (billing and discomfort costs) by up to 50% compared to existing
DSM strategies.


title: D$^3$PO - Denoising, Deconvolving, and Decomposing Photon Observations

abstract:
  The analysis of astronomical images is a non-trivial task. The D3PO algorithm
addresses the inference problem of denoising, deconvolving, and decomposing
photon observations. Its primary goal is the simultaneous but individual
reconstruction of the diffuse and point-like photon flux given a single photon
count image, where the fluxes are superimposed. In order to discriminate
between these morphologically different signal components, a probabilistic
algorithm is derived in the language of information field theory based on a
hierarchical Bayesian parameter model. The signal inference exploits prior
information on the spatial correlation structure of the diffuse component and
the brightness distribution of the spatially uncorrelated point-like sources. A
maximum a posteriori solution and a solution minimizing the Gibbs free energy
of the inference problem using variational Bayesian methods are discussed.
Since the derivation of the solution is not dependent on the underlying
position space, the implementation of the D3PO algorithm uses the NIFTY package
to ensure applicability to various spatial grids and at any resolution. The
fidelity of the algorithm is validated by the analysis of simulated data,
including a realistic high energy photon count image showing a 32 x 32 arcmin^2
observation with a spatial resolution of 0.1 arcmin. In all tests the D3PO
algorithm successfully denoised, deconvolved, and decomposed the data into a
diffuse and a point-like signal estimate for the respective photon flux
components.

categories: astro-ph.IM cs.IT math.IT physics.data-an stat.CO


title:
Configurable unitary transformations and linear logic gates using
  quantum memories

abstract:
  We show that a set of optical memories can act as a configurable linear
optical network operating on frequency-multiplexed optical states. Our protocol
is applicable to any quantum memories that employ off-resonant Raman
transitions to store optical information in atomic spins. In addition to the
configurability, the protocol also offers favourable scaling with an increasing
number of modes where N memories can be configured to implement an arbitrary
N-mode unitary operations during storage and readout. We demonstrate the
versatility of this protocol by showing an example where cascaded memories are
used to implement a conditional CZ gate.


title:
Discrepancy estimates for variance bounding Markov chain quasi-Monte
  Carlo

abstract:
  Markov chain Monte Carlo (MCMC) simulations are modeled as driven by true
random numbers. We consider variance bounding Markov chains driven by a
deterministic sequence of numbers. The star-discrepancy provides a measure of
efficiency of such Markov chain quasi-Monte Carlo methods. We define a
pull-back discrepancy of the driver sequence and state a close relation to the
star-discrepancy of the Markov chain-quasi Monte Carlo samples. We prove that
there exists a deterministic driver sequence such that the discrepancies
decrease almost with the Monte Carlo rate $n^{1/2}$. As for MCMC simulations, a
burn-in period can also be taken into account for Markov chain quasi-Monte
Carlo to reduce the influence of the initial state. In particular, our
discrepancy bound leads to an estimate of the error for the computation of
expectations. To illustrate our theory we provide an example for the Metropolis
algorithm based on a ball walk. Furthermore, under additional assumptions we
prove the existence of a driver sequence such that the discrepancy of the
corresponding deterministic Markov chain sample decreases with order
$n^{-1+\delta}$ for every $\delta>0$.


title: On cubic birational maps of $\mathbb{P}^3_\mathbb{C}$

abstract:
  We study the birational maps of $\mathbb{P}^3_\mathbb{C}$. More precisely we
describe the irreducible components of the set of birational maps of bidegree
$(3,3)$ (resp. $(3,4)$, resp. $(3,5)$).


title:
Evolutionary genetic optimization of the injector beam dynamics for the
  ERL test facility at IHEP

abstract:
  The energy recovery linac test facility (ERL-TF), a compact ERL-FEL (free
electron laser) two-purpose machine, was proposed at the Institute of High
Energy Physics, Beijing. As one important component of the ERL-TF, the
photo-injector started with a photocathode direct-current gun was designed and
preliminarily optimized. In this paper an evolutionary genetic method,
non-dominated sorting genetic algorithm II, is applied to optimize the injector
beam dynamics, especially in the high-charge operation mode. Study shows that
using an incident laser with rms transverse size of 1~1.2 mm, the normalized
emittance of the electron beam can be kept below 1 mm.mrad at the end of the
injector. This work, together with the previous optimization for the low-charge
operation mode by using the iterative scan method, provides guidance and
confidence for future constructing and commissioning of the ERL-TF injector.


title: Semiparametric testing of statistical functionals revisited

abstract:
  Along the lines of Janssen's and Pfanzagl's work the testing theory for
statistical functionals is further developed for non-parametric one-sample
problems. Efficient tests for the one-sided and two-sided problems are derived
for nonparametric statistical functionals. The asymptotic power function is
calculated under implicit alternatives and hypotheses, which are given by the
functional itself, for the one- sided and two-sided cases. Under mild
regularity assumptions it is shown that these tests are asymptotic most
powerful. The combination of the modern theory of Le Cam and approximation in
limit experiments provide a deep insight into the upper bounds for asymptotic
power functions of tests for the one-sided and two-sided problems. As example
tests based on the von Mises functional are treated in nonparametric context.


title: Optimality of Thompson Sampling for Gaussian Bandits Depends on Priors

abstract:
  In stochastic bandit problems, a Bayesian policy called Thompson sampling
(TS) has recently attracted much attention for its excellent empirical
performance. However, the theoretical analysis of this policy is difficult and
its asymptotic optimality is only proved for one-parameter models. In this
paper we discuss the optimality of TS for the model of normal distributions
with unknown means and variances as one of the most fundamental example of
multiparameter models. First we prove that the expected regret of TS with the
uniform prior achieves the theoretical bound, which is the first result to show
that the asymptotic bound is achievable for the normal distribution model. Next
we prove that TS with Jeffreys prior and reference prior cannot achieve the
theoretical bound. Therefore the choice of priors is important for TS and
non-informative priors are sometimes risky in cases of multiparameter models.


title: Mining Crash Fix Patterns

abstract:
  During the life cycle of software development, developers have to fix
different kinds of bugs reported by testers or end users. The efficiency and
effectiveness of fixing bugs have a huge impact on the reliability of the
software as well as the productivity of the development team. Software
companies usually spend a large amount of money and human resources on the
testing and bug fixing departments. As a result, a better and more reliable way
to fix bugs is highly desired by them. In order to achieve such goal, in depth
studies on the characteristics of bug fixes from well maintained, highly
popular software projects are necessary. In this paper, we study the bug fixing
histories extracted from the Eclipse project, a well maintained, highly popular
open source project. After analyzing more than 36,000 bugs that belongs to
three major kinds of exception types, we are able to reveal some common fix
types that are frequently used to fix certain kinds of program exceptions. Our
analysis shows that almost all of the exceptions that belong to a certain
exception can be fixed by less than ten fix types. Our result implies that most
of the bugs in software projects can be and should be fixed by only a few
common fix patterns.


title: Pseudogap-induced asymmetric tunneling in cuprate superconductors

abstract:
  The asymmetric tunneling in cuprate superconductors is studied based on the
kinetic energy driven superconducting mechanism. By taking into account the
interplay between the superconducting gap and normal-state pseudogap, the
essential feature of the evolution of the asymmetric tunneling with doping and
temperature is qualitatively reproduced. In particular, the asymmetry of the
tunneling spectrum in the underdoped regime weakens with increasing doping, and
then the symmetric tunneling spectrum recovers in the heavily overdoped regime.
The theory also shows that the asymmetric tunneling is a natural consequence
due to the presence of the normal-state pseudogap.


title: Logique math\'ematique et linguistique formelle

abstract:
  As the etymology of the word shows, logic is intimately related to language,
as exemplified by the work of philosophers from Antiquity and from the
Middle-Age. At the beginning of the XX century, the crisis of the foundations
of mathematics invented mathematical logic and imposed logic as a
language-based foundation for mathematics. How did the relations between logic
and language evolved in this newly defined mathematical framework? After a
survey of the history of the relation between logic and linguistics,
traditionally focused on semantics, we focus on some present issues: 1) grammar
as a deductive system 2) the transformation of the syntactic structure of a
sentence to a logical formula representing its meaning 3) taking into account
the context when interpreting words. This lecture shows that type theory
provides a convenient framework both for natural language syntax and for the
interpretation of any of tis level (words, sentences, discourse).


title:
Lower Bound on the Garvitino Mass $m_{3/2}>O(100)$ TeV in $R$-Symmetry
  Breaking New Inflation

abstract:
  In supersymmetric theories, the $R$ symmetry plays a unique role in
suppressing a constant term in the superpotential. In single chiral field
models of spontaneous breaking of a discrete $R$ symmetry, an $R$-breaking
field can be a good candidate for an inflaton in new inflation models. In this
paper, we revisit the compatibility of the single-field $R$-breaking new
inflation model with the results of the Planck experiment. As a result, we find
that the model predicts a lower limit on the gravitino mass, $m_{3/2}>O(100)$
TeV. This lower limit is consistent with the observed Higgs mass of 126 GeV
when the masses of the stops are of order the gravitino mass scale.


title: Computation of expectations by Markov chain Monte Carlo methods

abstract:
  Markov chain Monte Carlo (MCMC) methods are a very versatile and widely used
tool to compute integrals and expectations. In this short survey we focus on
error bounds, rules for choosing the burn in, high dimensional problems and
tractability versus curse of dimension.


title:
Some explicit formulas for the Brownian bridge, Brownian meander and
  Bessel process under uniform sampling

abstract:
  We show that simple explicit formulas can be obtained for several relevant
quantities related to the laws of the uniformly sampled Brownian bridge,
Brownian meander and three dimensional Bessel process. To prove such results,
we use the distribution of a triplet of random variables associated to the
pseudo-Brownian bridge together with various relationships between the laws of
these four processes.


title:
Multi-epoch VLBA H$_2$O maser observations toward the massive YSOs AFGL
  2591 VLA 2 and VLA 3

abstract:
  We present multi-epoch Very Long Baseline Array (VLBA) H$_2$O maser
observations toward the massive young stellar objects (YSOs) VLA 2 and VLA 3 in
the star-forming region AFGL 2591. Through these observations, we have extended
the study of the evolution of the masers towards these objects up to a time
span of $\sim$ 10 yrs, measuring their radial velocities and proper motions.
The H$_2$O masers in VLA 3, the most massive YSO in AFGL 2591 ($\sim$
30--40~M$_{\odot}$), are grouped within projected distances of $\lesssim$ 40
mas ($\lesssim$ 130 AU) from VLA 3. In contrast to other H$_2$O masers in AFGL
2591, the masers associated with VLA 3 are significantly blueshifted (up to
$\sim$ 30 km s$^{-1}$) with respect to the velocity of the ambient molecular
cloud. We find that the H$_2$O maser cluster as a whole, has moved westwards of
VLA~3 between the 2001 and 2009 observations, with a proper motion of $\sim$
1.2 mas yr$^{-1}$ ($\sim$ 20 km s$^{-1}$). We conclude that these masers are
tracing blueshifted outflowing material, shock excited at the inner parts of a
cavity seen previously in ammonia molecular lines and infrared images, and
proposed to be evacuated by the outflow associated with the massive VLA 3
source. The masers in the region of VLA 2 are located at projected distances of
$\sim$ 0.7$''$ ($\sim$ 2300 AU) north from this source, with their kinematics
suggesting that they are excited by a YSO other than VLA 2. This driving source
has not yet been identified.


title: Maximal Regularity for Non-Autonomous Second Order Cauchy Problems

abstract:
  We consider non-autonomous wave equations \[ \left\{ \begin{aligned} \&\ddot
u(t) + \B(t)\dot u(t) + \A(t)u(t) = f(t) \quad t\text{-a.e.}\\ \&u(0)=u_0,\,
\dot u(0) = u_1. \end{aligned} \right. \] where the operators $\A(t)$ and
$\B(t)$ are associated with time-dependent sesquilinear forms $\fra(t,.,.)$ and
$\frb$ defined on a Hilbert space $H$ with the same domain $V$. The initial
values satisfy $ u_0 \in V$ and $u_1 \in H$. We prove well-posedness and
maximal regularity for the solution both in the spaces $V'$ and $H$. We apply
the results to non-autonomous Robin-boundary conditions and also use maximal
regularity to solve a quasilinear problem.


title: Moment-based Uniform Deviation Bounds for $k$-means and Friends

abstract:
  Suppose $k$ centers are fit to $m$ points by heuristically minimizing the
$k$-means cost; what is the corresponding fit over the source distribution?
This question is resolved here for distributions with $p\geq 4$ bounded
moments; in particular, the difference between the sample cost and distribution
cost decays with $m$ and $p$ as $m^{\min\{-1/4, -1/2+2/p\}}$. The essential
technical contribution is a mechanism to uniformly control deviations in the
face of unbounded parameter sets, cost functions, and source distributions. To
further demonstrate this mechanism, a soft clustering variant of $k$-means cost
is also considered, namely the log likelihood of a Gaussian mixture, subject to
the constraint that all covariance matrices have bounded spectrum. Lastly, a
rate with refined constants is provided for $k$-means instances possessing some
cluster structure.


title: On projections of smooth and nodal plane curves

abstract:
  Suppose that $C\subset\mathbb P^2$ is a general enough nodal plane curve of
degree $>2$, $\nu\colon \hat C\to C$ is its normalization, and $\pi\colon \hat
C\to\mathbb P^1$ is a finite morphism simply ramified over the same set of
points as a projection $\mathrm{pr}_p\circ \nu\colon\hat C \to\mathbb P^1$,
where $p\in\mathbb P^2\setminus C$ (if $\mathrm{deg}\, C=3$, one should assume
in addition that $\deg\pi\ne4$). We prove that the morphism $\pi$ is equivalent
to such a projection if and only if it extends to a finite morphism
$X\to(\mathbb P^2)^*$ ramified over $C^*$, where $X$ is a smooth surface.
  As a by-product, we prove the Chisini conjecture for mappings ramified over
duals to general nodal curves of any degree $\ge3$ except for duals to smooth
cubics; this strengthens one of Victor Kulikov's results.


title: A discrete integrability test based on multiscale analysis

abstract:
  In this article we present the results obtained applying the multiple scale
expansion up to the order \epsilon^6 to a dispersive multilinear class of
equations on a square lattice depending on 13 parameters. We show that the
integrability conditions given by the multiple scale expansion give rise to 4
nonlinear equations, 3 of which are new, depending at most on 2 parameters and
containing integrable sub cases. Moreover at least one sub case provides an
example of a new integrable system.


title:
A practical GMSB model for explaining the muon (g-2) with gauge coupling
  unification

abstract:
  We present a gauge mediated supersymmetry breaking model having weak SU(2)
triplet, color SU(3) octet and SU(5) 5-plet messengers, that can simultaneously
explain the muon $(g-2)$ data within 1$\sigma$ and the observed Higgs boson
mass of 125 GeV. Gauge coupling unification is nontrivially maintained. Most of
the parameter space satisfying both is accessible to the 14 TeV LHC. The
lighter of the two staus weighs around (100-200) GeV, which can be a potential
target of the ILC.


title:
Proactive bottleneck performance analysis in parallel computing using
  openMP

abstract:
  The aim of parallel computing is to increase an application performance by
executing the application on multiple processors. OpenMP is an API that
supports multi platform shared memory programming model and shared-memory
programs are typically executed by multiple threads. The use of multi threading
can enhance the performance of application but its excessive use can degrade
the performance. This paper describes a novel approach to avoid bottlenecks in
application and provide some techniques to improve performance in OpenMP
application. This paper analyzes bottleneck performance as bottleneck inhibits
performance. Performance of multi threaded applications is limited by a variety
of bottlenecks, e.g. critical sections, barriers and so on. This paper provides
some tips how to avoid performance bottleneck problems. This paper focuses on
how to reduce overheads and overall execution time to get better performance of
application.


title:
First results of proton antiproton annihilation into a pion pair at
  large scattering angles within the handbag approach

abstract:
  We propose to describe the process $ p ~ \bar{p} \rightarrow \pi^+ ~ \pi^-$
in a perturbative, QCD motivated framework in which a hard $ud \, \bar{u}
\bar{d} \rightarrow d \, \bar{d} $ annihilation factorizes from soft transition
distribution amplitudes. We advocate that the scale allowing for this
factorization is the large transverse momentum transfer. In our simplified
model, in which the proton is considered as a (scalar)diqark-quark system, a
transition distribution amplitude describes the non-perturbative transition of
the proton to the meson by emission of a scalar, isoscalar $ ud $-diquark and
absorption of an antiquark (analogously for $ \bar{p} \rightarrow \pi^- $). We
model the transition distribution amplitudes as an overlap of light-cone wave
functions and present first results for the differential cross section. This
process will be measured by the $ \bar{\mbox{P}}$ANDA experiment at GSI-FAIR.


title:
A Khovanov type invariant derived from an unoriented HQFT for links in
  thickened surfaces

abstract:
  Two link diagrams on compact surfaces are strongly equivalent if they are
related by Reidemeister moves and orientation preserving homeomorphisms of the
surfaces. They are stably equivalent if they are related by the two previous
operations and adding or removing handles. Turaev and Turner constructed a link
homology for each stable equivalence class by applying an unoriented
topological quantum field theory (TQFT) to a geometric chain complex similar to
Bar-Natan's one. In this paper, by using an unoriented homotopy quantum field
theory (HQFT), we construct a link homology for each strong equivalence class.
Moreover, our homology yields an invariant of links in the oriented I-bundle of
a compact surface.


title: The hemagglutinin mutation E391K of pandemic 2009 influenza revisited

abstract:
  Phylogenetic analyses based on small to moderately sized sets of sequential
data lead to overestimating mutation rates in influenza hemagglutinin (HA) by
at least an order of magnitude. Two major underlying reasons are: the
incomplete lineage sorting, and a possible absence in the analyzed sequences
set some of key missing ancestors. Additionally, during neighbor joining tree
reconstruction each mutation is considered equally important, regardless of its
nature. Here we have implemented a heuristic method optimizing site dependent
factors weighting differently 1st, 2nd, and 3rd codon position mutations,
allowing to extricate incorrectly attributed sub-clades. The least squares
regression analysis of distribution of frequencies for all mutations observed
on a partially disentangled tree for a large set of unique 3243 HA sequences,
along all nucleotide positions, was performed for all mutations as well as for
non-equivalent amino acid mutations: in both cases demonstrating almost flat
gradients, with a very slight downward slope towards the 3'-end positions. The
mean mutation rates per sequence per year were 3.83*10^-4 for the all
mutations, and 9.64*10^-5 for the non-equivalent ones.


title:
Visualizing the Effects of a Changing Distance on Data Using Continuous
  Embeddings

abstract:
  Most Machine Learning (ML) methods, from clustering to classification, rely
on a distance function to describe relationships between datapoints. For
complex datasets it is hard to avoid making some arbitrary choices when
defining a distance function. To compare images, one must choose a spatial
scale, for signals, a temporal scale. The right scale is hard to pin down and
it is preferable when results do not depend too tightly on the exact value one
picked. Topological data analysis seeks to address this issue by focusing on
the notion of neighbourhood instead of distance. It is shown that in some cases
a simpler solution is available. It can be checked how strongly distance
relationships depend on a hyperparameter using dimensionality reduction. A
variant of dynamical multi-dimensional scaling (MDS) is formulated, which
embeds datapoints as curves. The resulting algorithm is based on the
Concave-Convex Procedure (CCCP) and provides a simple and efficient way of
visualizing changes and invariances in distance patterns as a hyperparameter is
varied. A variant to analyze the dependence on multiple hyperparameters is also
presented. A cMDS algorithm that is straightforward to implement, use and
extend is provided. To illustrate the possibilities of cMDS, cMDS is applied to
several real-world data sets.


title: Complete independence of an axiom system for central translations

abstract:
  A recently proposed axiom system for Andr\'e's central translation structures
is improved upon. First, one of its axioms turns out to be dependent (derivable
from the other axioms). Without this axiom, the axiom system is indeed
independent. Second, whereas most of the original independence models were
infinite, finite independence models are available. Moreover, the independence
proof for one of the axioms employed proof-theoretic techniques rather than
independence models; for this axiom, too, a finite independence model exists.
For every axiom, then, there is a finite independence model. Finally, the axiom
system (without its single dependent axiom) is not only independent, but
completely independent.


title:
Recent Results on Isospin-Violating Transitions in Charmonium Studied
  with BESIII

abstract:
  Charmonium spectroscopy provides strong guidelines to effective field
theories, thereby gaining insight into quark confinement and the generation of
hadron masses. Hadronic transitions between charmonium states have been
measured with unprecedented high precision with the BESIII spectrometer at IHEP
Beijing, China. We present systematic studies of isospin-violating decays in
charmonium, such as $\psi' \rightarrow \pi^{0} J/\psi$, $\psi' \rightarrow
\pi^{0} h_{c}$, $e^{+}e^{-} \rightarrow \pi^{0} J/\psi$ at $\sqrt{s}=$ 4.009
GeV, and their improved measurements of their branching fractions.


title: Solar-like oscillations in subgiant and red-giant stars: mixed modes

abstract:
  Thanks to significant improvements in high-resolution spectrographs and the
launch of dedicated space missions MOST, CoRoT and Kepler, the number of
subgiants and red-giant stars with detected oscillations has increased
significantly over the last decade. The amount of detail that can now be
resolved in the oscillation patterns does allow for in-depth investigations of
the internal structures of these stars. One phenomenon that plays an important
role in such studies are mixed modes. These are modes that carry information of
the inner radiative region as well as from the convective outer part of the
star allowing to probe different depths of the stars.
  Here, we describe mixed modes and highlight some recent results obtained
using mixed modes observed in subgiants and red-giant stars.


title: Sentence complexity of theorems in Mizar

abstract:
  As one of the longest-running computer-assisted formal mathematics projects,
large tracts of mathematical knowledge have been formalized with the help of
the Mizar system. Because Mizar is based on first-order classical logic and set
theory, and because of its emphasis on pure mathematics, the Mizar library
offers a cornucopia for the researcher interested in foundations of
mathematics. With Mizar, one can adopt an experimental approach and take on
problems in foundations, at least those which are amenable to such
experimentation. Addressing a question posed by H. Friedman, we use Mizar to
take on the question of surveying the sentence complexity (measured by
quantifier alternation) of mathematical theorems. We find, as Friedman
suggests, that the sentence complexity of most Mizar theorems is universal
($\Pi_{1}$, or $\forall$), and as one goes higher in the sentence complexity
hierarchy the number of Mizar theorems having these complexities decreases
rapidly. The results support the intuitive idea that mathematical statements,
even when carried out an abstract set-theoretical style, are usually quite low
in the sentence complexity hierarchy (not more complex than
$\forall\exists\forall$ or $\exists\forall$).


title: Ordered Models of the Lambda Calculus

abstract:
  Answering a question by Honsell and Plotkin, we show that there are two
equations between lambda terms, the so-called subtractive equations, consistent
with lambda calculus but not simultaneously satisfied in any partially ordered
model with bottom element. We also relate the subtractive equations to the open
problem of the order-incompleteness of lambda calculus, by studying the
connection between the notion of absolute unorderability in a specific point
and a weaker notion of subtractivity (namely n-subtractivity) for partially
ordered algebras. Finally we study the relation between n-subtractivity and
relativized separation conditions in topological algebras, obtaining an
incompleteness theorem for a general topological semantics of lambda calculus.


title: Toward a structure theory for Lorenzen dialogue games

abstract:
  Lorenzen dialogues provide a two-player game formalism that can characterize
a variety of logics: each set $S$ of rules for such a game determines a set
$\mathcal{D}(S)$ of formulas for which one of the players (the so-called
Proponent) has a winning strategy, and the set $\mathcal{D}(S)$ can coincide
with various logics, such as intuitionistic, classical, modal, connexive, and
relevance logics. But the standard sets of rules employed for these games are
often logically opaque and can involve subtle interactions among each other.
Moreover, $\mathcal{D}(S)$ can vary in unexpected ways with $S$; small changes
in $S$, even logically well-motivated ones, can make $\mathcal{D}(S)$ logically
unusual. We pose the problem of providing a structure theory that could explain
how $\mathcal{D}(S)$ varies with $S$, and in particular, when $\mathcal{D}(S)$
is closed under modus ponens (and thus constitutes at least a minimal kind of
logic).


title: On Sudakov's type decomposition of transference plans with norm costs

abstract:
  We consider the original strategy proposed by Sudakov for solving the Monge
transportation problem with norm cost $|\cdot|_{D^*}$ \[ \min \bigg\{\int
|\mathtt T(x) - x|_{D^*} d\mu(x), \ \mathtt T : \mathbb R^d \to \mathbb R^d, \
\nu = \mathtt T_\# \mu \bigg\}, \] with $\mu$, $\nu$ probability measures in
$\mathbb R^d$ and $\mu$ absolutely continuous w.r.t. $\mathcal L^d$. The key
idea in this approach is to decompose (via disintegration of measures) the
Kantorovich optimal transportation problem into a family of transportation
problems in $Z_\mathfrak a\times\mathbb R^d$, where $\{Z_\mathfrak
a\}_{\mathfrak a\in\mathfrak A} \subset \mathbb R^d$ are disjoint regions such
that the construction of an optimal map $\mathtt T_\mathfrak a : Z_\mathfrak a
\to \mathbb R^d$ is simpler than in the original problem, and then to obtain
$\mathtt T$ by piecing together the maps $\mathtt T_\mathfrak a$. In this paper
we show how the original idea of Sudakov can be successfully implemented. The
results yield a complete characterization of the Kantorovich optimal
transportation problem, whose straightforward corollary is the solution of the
Monge problem in each set $Z_\mathfrak a$ and then in $\mathbb R^d$. The
strategy is sufficiently powerful to be applied to other optimal transportation
problems.


title: Heterogeneous Delays in Neural Networks

abstract:
  We investigate heterogeneous coupling delays in complex networks of excitable
elements described by the FitzHugh-Nagumo model. The effects of discrete as
well as of uni- and bimodal continuous distributions are studied with a focus
on different topologies, i.e., regular, small-world, and random networks. In
the case of two discrete delay times resonance effects play a major role:
Depending on the ratio of the delay times, various characteristic spiking
scenarios, such as coherent or asynchronous spiking, arise. For continuous
delay distributions different dynamical patterns emerge depending on the width
of the distribution. For small distribution widths, we find highly synchronized
spiking, while for intermediate widths only spiking with low degree of
synchrony persists, which is associated with traveling disruptions, partial
amplitude death, or subnetwork synchronization, depending sensitively on the
network topology. If the inhomogeneity of the coupling delays becomes too
large, global amplitude death is induced.


title: Generalized coherent states

abstract:
  In the coherent state of the harmonic oscillator, the probability density is
that of the ground state subjected to an oscillation along a classical
trajectory. Senitzky and others pointed out that there are states of the
harmonic oscillator corresponding to an identical oscillatory displacement of
the probability density of any energy eigenstate. These generalizations of the
coherent state are rarely discussed, yet they furnish an interesting set of
quantum states of light that combine features of number states and coherent
states. Here we give an elementary account of the quantum optics of generalized
coherent states.


title:
Diffuse optical intracluster light as a measure of stellar tidal
  stripping: the cluster CL0024+17 at $z\sim $0.4 observed at LBT

abstract:
  We have evaluated the diffuse intracluster light (ICL) in the central core of
the galaxy cluster CL0024+17 at $z\sim 0.4$ observed with the prime focus
camera (LBC) at LBT. The measure required an accurate removal of the galaxies
light within $\sim 200$ kpc from the center. The residual background intensity
has then been integrated in circular apertures to derive the average ICL
intensity profile. The latter shows an approximate exponential decline as
expected from theoretical cold dark matter models. The radial profile of the
ICL over the galaxies intensity ratio (ICL fraction) is increasing with
decreasing radius but near the cluster center it starts to bend and then
decreases where the overlap of the halos of the brightest cluster galaxies
becomes dominant. Theoretical expectations in a simplified CDM scenario show
that the ICL fraction profile can be estimated from the stripped over galaxy
stellar mass ratio in the cluster. It is possible to show that the latter
quantity is almost independent of the properties of the individual host
galaxies but mainly depends on the average cluster properties. The predicted
ICL fraction profile is thus very sensitive to the assumed CDM profile, total
mass and concentration parameter of the cluster. Adopting values very similar
to those derived from the most recent lensing analysis in CL0024+17 we find a
good agreement with the observed ICL fraction profile. The galaxy counts in the
cluster core have then been compared with that derived from composite cluster
samples in larger volumes, up to the clusters virial radius. The galaxy counts
in the CL0024+17 core appear flatter and the amount of bending respect to the
average cluster galaxy counts imply a loss of total emissivity in broad
agreement with the measured ICL fraction.


title:
Discrete Filters for Large Eddy Simulation of Forced Compressible MHD
  Turbulence

abstract:
  In present study, we discuss results of applicability of discrete filters for
large eddy simulation (LES) method of forced compressible magnetohydrodynamic
(MHD) turbulent flows with the scale-similarity model. Influences and effects
of discrete filter shapes on the scale-similarity model are examined in
physical space using a finite-difference numerical schemes. We restrict
ourselves to the Gaussian filter and the top-hat filter. Representations of
this subgrid-scale model which correspond to various 3- and 5-point
approximations of both Gaussian and top-hat filters for different values of
parameter $\epsilon$ (the ratio of the mesh size to the cut-off lengthscale of
the filter) are investigated. Discrete filters produce more discrepancies for
magnetic field. It is shown that the Gaussian filter is more sensitive to the
parameter $\epsilon$ than the top-hat filter in compressible forced MHD
turbulence. The 3-point filters at $\epsilon=2$ and $\epsilon=3$ give the least
accurate results and the 5-point Gaussian filter shows the best results at
$\epsilon=2$.


title:
Convergence rates in $\ell^1$-regularization when the basis is not
  smooth enough

abstract:
  Sparsity promoting regularization is an important technique for signal
reconstruction and several other ill-posed problems. Theoretical investigation
typically bases on the assumption that the unknown solution has a sparse
representation with respect to a fixed basis. We drop this sparsity assumption
and provide error estimates for non-sparse solutions. After discussing a result
in this direction published earlier by one of the authors and coauthors we
prove a similar error estimate under weaker assumptions. Two examples
illustrate that this set of weaker assumptions indeed covers additional
situations which appear in applications.


title: Community detection for correlation matrices

abstract:
  A challenging problem in the study of complex systems is that of resolving,
without prior information, the emergent, mesoscopic organization determined by
groups of units whose dynamical activity is more strongly correlated internally
than with the rest of the system. The existing techniques to filter
correlations are not explicitly oriented towards identifying such modules and
can suffer from an unavoidable information loss. A promising alternative is
that of employing community detection techniques developed in network theory.
Unfortunately, this approach has focused predominantly on replacing network
data with correlation matrices, a procedure that tends to be intrinsically
biased due to its inconsistency with the null hypotheses underlying the
existing algorithms. Here we introduce, via a consistent redefinition of null
models based on random matrix theory, the appropriate correlation-based
counterparts of the most popular community detection techniques. Our methods
can filter out both unit-specific noise and system-wide dependencies, and the
resulting communities are internally correlated and mutually anti-correlated.
We also implement multiresolution and multifrequency approaches revealing
hierarchically nested sub-communities with `hard' cores and `soft' peripheries.
We apply our techniques to several financial time series and identify
mesoscopic groups of stocks which are irreducible to a standard, sectorial
taxonomy, detect `soft stocks' that alternate between communities, and discuss
implications for portfolio optimization and risk management.

categories: physics.data-an physics.soc-ph q-fin.PM q-fin.RM q-fin.ST


title: On the Friedel sum rule in ab initio calculations of optical properties

abstract:
  We investigate the influence of technical parameters in dynamic electrical
conductivity calculations by the Kubo-Greenwood formula on the value of the
so-called sum rule. We propose a possible explanation of the slight
overestimation of the sum rule in most of our results.


title: Finite time interaction quench in a Luttinger model

abstract:
  We analyze the dynamics of a Luttinger model following a quench in the
electron-electron interaction strength, where the change in the interaction
strength occurs over a finite time scale $\tau$. We study the Loschmidt echo
(the overlap between the initial and final state) as a function of time, both
numerically and within a perturbation scheme, treating the change in the
interaction as a small parameter, for all $\tau$. We derive the corrections
appearing in, a.) the Loschmidt echo for a finite quench duration $\tau$, b.)
the scaling of the echo following a sudden ($\tau \to 0$) quench, and c.) the
scaling of the echo after an adiabatic ($\tau \to \infty$) quench. We study in
detail, the limiting cases of the echo in the early time and infinite time
limit, and provide scaling arguments to understand these in a general context.
We also show that our perturbative results are in good agreement with the exact
numerical ones.


title: Conjugate observations of Saturn's northern and southern H3+ aurorae

abstract:
  We present an analysis of recent high spatial and spectral resolution
ground-based infrared observations of H3+ spectra obtained with the 10-metre
Keck II telescope in April 2011. We observed H3+ emission from Saturn's
northern and southern auroral regions, simultaneously, over the course of more
than two hours, obtaining spectral images along the central meridian as Saturn
rotates. Previous ground-based work has derived only an average temperature of
an individual polar region, summing an entire night of observations. Here we
analyse 20 H3+ spectra, 10 for each hemisphere, providing H3+ temperature,
column density and total emission in both the northern and southern polar
regions simultaneously, improving on past results in temporal cadence and
simultaneity. We find that: 1) the average thermospheric temperatures are
527+/-18 K in northern Spring and 583+/-13 K in southern Autumn, respectively;
2) this asymmetry in temperature is likely to be the result of an inversely
proportional relationship between the total thermospheric heating rate (Joule
heating and ion drag) and magnetic field strength - i.e. the larger northern
field strength leads to reduced total heating rate and a reduced temperature,
irrespective of season, and 3) this implies that thermospheric heating and
temperatures are relatively insensitive to seasonal effects.


title: On Uni Chord Free Graphs

abstract:
  A graph is unichord free if it does not contain a cycle with exactly one
chord as its subgraph. In [3], it is shown that a graph is unichord free if and
only if every minimal vertex separator is a stable set. In this paper, we first
show that such a graph can be recognized in polynomial time. Further, we show
that the chromatic number of unichord free graphs is one of (2,3, \omega(G)).
We also present a polynomial-time algorithm to produce a coloring with
\omega(G) colors.


title:
Normal complex surface singularities with rational homology disk
  smoothings

abstract:
  In this paper we show that if the minimal good resolution graph of a normal
surface singularity contains at least two nodes (i.e. vertex with valency at
least 3) then the singularity does not admit a smoothing with Milnor fiber
having rational homology equal to the rational homology of the 4-disk $D^4$
(called a rational homology disk smoothing). Combining with earlier results,
this theorem then provides a complete classification of resolution graphs of
normal surface singularities with a rational homology disk smoothing, verifying
a conjecture of J. Wahl regarding such singularities. Indeed, together with a
recent result of J. Fowler we get the complete list of normal surface
singularities which admit rational homology disk smoothings.


title: Outer Billiards and Tilings of the Hyperbolic Plane

abstract:
  In this paper we present new results regarding the periodicity of outer
billiards in the hyperbolic plane around polygonal tables which are tiles in
regular two-piece tilings of the hyperbolic plane.


title:
Function-theoretic properties for the Gauss maps of various classes of
  surfaces

abstract:
  We elucidate the geometric background of function-theoretic properties for
the Gauss maps of several classes of immersed surfaces in three-dimensional
space forms, for example, minimal surfaces in Euclidean three-space, improper
affine spheres in the affine three-space, and constant mean curvature one
surfaces and flat surfaces in hyperbolic three-space. To achieve this purpose,
we prove an optimal curvature bound for a specified conformal metric on an open
Riemann surface and give some applications. We also provide unicity theorems
for the Gauss maps of these classes of surfaces.


title: Magnetic field of the classical Cepheid $\eta$ Aql: new results

abstract:
  We present the results of the spectropolarimetric study of the classical
Cepheid $\eta$ Aql in 2002, 2004, 2010, and 2012. The longitudinal magnetic
field of $\eta$ Aql was found to be variable with the pulsation cycle of
7.176726 day. The amplitude, phase, and mean value of the field vary from year
to year presumably due to stellar rotation or dynamo mechanisms.


title: Extraordinary absorption of sound in porous lamella-crystals

abstract:
  We present the design of a structured material supporting complete absorption
of sound with a broadband response and functional for any direction of incident
radiation. The structure which is fabricated out of porous lamellas is arranged
into a low-density crystal and backed by a reflecting support. Experimental
measurements show that strong all-angle sound absorption with almost zero
reflectance takes place for a frequency range exceeding two octaves. We
demonstrate that lowering the crystal filling fraction increases the wave
interaction time and is responsible for the enhancement of intrinsic material
dissipation, making the system more absorptive with less material.


title:
Discretization Errors for the Gluon and Ghost Propagators in Landau
  Gauge using NSPT

abstract:
  The subtraction of hypercubic lattice corrections, calculated at 1-loop order
in lattice perturbation theory (LPT), is common practice, e.g., for
determinations of renormalization constants in lattice hadron physics.
Providing such corrections beyond 1-loop order is however very demanding in
LPT, and numerical stochastic perturbation theory (NSPT) might be the better
candidate for this. Here we report on a first feasibility check of this method
and provide (in a parametrization valid for arbitrary lattice couplings) the
lattice corrections up to 3-loop order for the SU(3) gluon and ghost
propagators in Landau gauge. These propagators are ideal candidates for such a
check, as they are available from lattice simulations to high precision and can
be combined to a renormalization group invariant product (Minimal MOM coupling)
for which a 1-loop LPT correction was found to be insufficient to remove the
bulk of the hypercubic lattice artifacts from the data. As a bonus, we also
compare our results with the ever popular H(4) method.


title:
Unsupervised learning human's activities by overexpressed recognized
  non-speech sounds

abstract:
  Human activity and environment produces sounds such as, at home, the noise
produced by water, cough, or television. These sounds can be used to determine
the activity in the environment. The objective is to monitor a person's
activity or determine his environment using a single low cost microphone by
sound analysis. The purpose is to adapt programs to the activity or environment
or detect abnormal situations. Some patterns of over expressed repeatedly in
the sequences of recognized sounds inter and intra environment allow to
characterize activities such as the entrance of a person in the house, or a tv
program watched. We first manually annotated 1500 sounds of daily life activity
of old persons living at home recognized sounds. Then we inferred an ontology
and enriched the database of annotation with a crowed sourced manual annotation
of 7500 sounds to help with the annotation of the most frequent sounds. Using
learning sound algorithms, we defined 50 types of the most frequent sounds. We
used this set of recognizable sounds as a base to tag sounds and put tags on
them. By using over expressed number of motifs of sequences of the tags, we
were able to categorize using only a single low-cost microphone, complex
activities of daily life of a persona at home as watching TV, entrance in the
apartment of a person, or phone conversation including detecting unknown
activities as repeated tasks performed by users.


title: Hadron structure within the point form of relativistic quantum mechanics

abstract:
  We present an outline of recent developments in the field of hadron
form-factor calculations within constituent-quark models using the point form
of relativistic quantum mechanics. Our method to calculate currents and form
factors is exemplified by means of the weak $B\rightarrow D$ transition. We
present results for weak $B\rightarrow D$ transition form factors in the space-
and the time-like momentum-transfer region. We discuss how wrong cluster
properties, which one has to deal with when employing relativistic quantum
mechanics, affect these form factors and we estimate the role non-valence,
Z-graph contributions may play for decay kinematics.


title:
Random Currents and Continuity of Ising Model's Spontaneous
  Magnetization

abstract:
  The spontaneous magnetization is proved to vanish continuously at the
critical temperature for a class of ferromagnetic Ising spin systems which
includes the nearest neighbor ferromagnetic Ising spin model on $\mathbb Z^d$
in $d=3$ dimensions. The analysis applies also to higher dimensions, for which
the result is already known, and to systems with interactions of power law
decay. The proof employs in an essential way an extension of Ising model's
random current representation to the model's infinite volume limit. Using it,
we relate the continuity of the magnetization to the vanishing of the free
boundary condition Gibbs state's Long Range Order parameter. For reflection
positive models the resulting criterion for continuity may be established
through the infrared bound for all but the borderline case, of the one
dimensional model with $1/r^2$ interaction, for which the spontaneous
magnetization is known to be discontinuous at $T_c$.


title:
Electromagnetic excitation of nuclei and neutron evaporation in
  ultrarelativistic ultraperipheral heavy ion collisions

abstract:
  We present a new approach for calculating electromagnetic excitation of
nuclei as well as probabilities of emission and distributions of neutrons from
decays of excited nuclear systems for ultrarelativistic, ultraperipheral heavy
ion collisions. Excitation functions for $\gamma$ + Pb $\to$ Pb$^*$ are
parametrized using physics-motivated components: excitation of giant
resonances, quasi-deuteron absorption mechanism, excitation of nucleon
resonances as well as high-energy dissociation of protons and neutrons. Neutron
emission (up to 10 neutrons) from low-energy excitations of $^{208}$Pb is
modelled in terms of the Hauser-Feshbach formalism. The probabilities of a
given number of neutrons are calculated as a function of excitation energy in a
Monte-Carlo code GEMINI. These functions are parametrized by smooth analytical
functions. The results are compared to appropriate data for the $\gamma$ Pb
$\to$ Pb$^*$ $\to$ k n reaction. As an example the approach is used for
calculating electromagnetic excitation in UPC processes. Both single photon and
double photon excitations are included and discussed. Topological cross
sections with a given number of neutrons in forward and backward directions are
calculated in the calculation at the LHC energies. Excitation functions are
presented. The results of calculation are compared with SPS and more recent
ALICE experimental data and good agreement is achieved.


title: Fast Tracking via Spatio-Temporal Context Learning

abstract:
  In this paper, we present a simple yet fast and robust algorithm which
exploits the spatio-temporal context for visual tracking. Our approach
formulates the spatio-temporal relationships between the object of interest and
its local context based on a Bayesian framework, which models the statistical
correlation between the low-level features (i.e., image intensity and position)
from the target and its surrounding regions. The tracking problem is posed by
computing a confidence map, and obtaining the best target location by
maximizing an object location likelihood function. The Fast Fourier Transform
is adopted for fast learning and detection in this work. Implemented in MATLAB
without code optimization, the proposed tracker runs at 350 frames per second
on an i7 machine. Extensive experimental results show that the proposed
algorithm performs favorably against state-of-the-art methods in terms of
efficiency, accuracy and robustness.


title: Power Decoding of Reed-Solomon Codes Revisited

abstract:
  Power decoding, or "decoding by virtual interleaving", of Reed--Solomon codes
is a method for unique decoding beyond half the minimum distance. We give a new
variant of the Power decoding scheme, building upon the key equation of Gao. We
show various interesting properties such as behavioural equivalence to the
classical scheme using syndromes, as well as a new bound on the failure
probability when the powering degree is 3.


title:
The Moduli Space of Heterotic Line Bundle Models: a Case Study for the
  Tetra-Quadric

abstract:
  It has recently been realised that polystable, holomorphic sums of line
bundles over smooth Calabi-Yau three-folds provide a fertile ground for
heterotic model building. Large numbers of phenomenologically promising such
models have been constructed for various classes of Calabi-Yau manifolds. In
this paper we focus on a case study for the tetra-quadric - a Calabi-Yau
hypersurface embedded in a product of four CP1 spaces. We address the question
of finiteness of the class of consistent and physically viable line bundle
models constructed on this manifold. Further, for a specific semi-realistic
example, we explore the embedding of the line bundle sum into the larger moduli
space of non-Abelian bundles, both by means of constructing specific polystable
non-Abelian bundles and by turning on VEVs in the associated low-energy theory.
In this context, we explore the fate of the Higgs doublets as we move in bundle
moduli space. The non-Abelian compactifications thus constructed lead to SU(5)
GUT models with an additional global B-L symmetry. The non-Abelian
compactifications inherit many of the appealing phenomenological features of
the Abelian model, such as the absence of dimension four and dimension five
operators triggering fast proton decay.


title: ELM Processes and Properties in 2T 2MA JET Plasmas

abstract:
  During July 2012, 150 almost identical H-mode plasmas were consecutively
created in the Joint European Torus (JET), providing a combined total of
approximately 8 minutes of steady-state plasma with 15,000 Edge Localised Modes
(ELMs). In principle, each of those 15,000 ELMs are statistically equivalent.
Here the changes in edge density and plasma energy associated with those ELMs
are explored, using the spikes in Beryllium II (527 nm) radiation as an
indicator for the onset of an ELM. Two timescales are found during the ELM
process. The first timescale is associated with the density drop, and the
second (longer) timescale is associated with a reduction in MHD energy that is
consistent with a resistive relaxation of the plasma's edge. The statistical
properties of the energy and density losses due to the ELMs are explored.
Surprisingly the commonly reported link between ELM energy (E) and ELM
frequency (f), of E proportional to 1/f, is not found. Instead beyond the first
0.02 seconds of waiting time between ELMs, the energy losses due to the ELMs
are found to be statistically the same. Surprisingly no correlation is found
between the energies of consecutive ELMs either. A weak link is found between
the density drop and the ELM waiting time. Consequences of these results for
ELM control and modelling are discussed.


title:
Spectropolarimetric study of the classical Cepheid $\eta$ Aql: pulsation
  and magnetic field

abstract:
  We report the results of spectropolarimetric study of the classical Cepheid
$\eta$ Aql. We found that the longitudinal magnetic field of $\eta$ Aql
sinusoidally varies with the radial pulsation period, while the amplitude $B$,
mean field $B_0$, and phases of maximum and minimum field change from year to
year. We hypothesize that possible reasons of those variations are stellar
axial rotation or dynamo mechanisms.


title:
Low-Contact-Resistance Graphene Devices with Nickel-Etched-Graphene
  Contacts

abstract:
  The performance of graphene-based transistors is often limited by the large
electrical resistance across the metal-graphene contact. We report an approach
to achieve ultra-low resistance metal contacts to graphene transistors. Through
a process of metal-catalyzed etching in hydrogen, multiple nano-sized pits with
zigzag edges are created in the graphene that form strong chemical bonds with
deposited nickel metallization for source-drain contacts without the need for
further annealing. This facile contact treatment prior to electrode
metallization results in contact resistance as low as 100 ohm-um in
single-layer graphene field-effect transistors, and 11 ohm-um in bilayer
graphene transistors. The treatment is compatible with complementary
metal-oxide-semiconductor fabrication processes, and holds great promise to
meet the contact performance required for the integration of graphene in future
integrated circuits.