title: Differential graded categories and Deligne conjecture

abstract:
  We prove a version of the Deligne conjecture for $n$-fold monoidal abelian
categories $A$ over a field $k$ of characteristic 0, assuming some
compatibility and non-degeneracy conditions for $A$. The output of our
construction is a weak Leinster $(n,1)$-algebra over $k$, a relaxed version of
the concept of Leinster $n$-algebra in $Alg(k)$. The difference between the
Leinster original definition and our relaxed one is apparent when $n>1$, for
$n=1$ both concepts coincide.
  We believe that there exists a functor from weak Leinster $(n,1)$-algebras
over $k$ to $C(E_{n+1},k)$-algebras, well-defined when $k=\mathbb{Q}$, and
preserving weak equivalences. For the case $n=1$ such a functor is constructed
in [Sh4] by elementary simplicial methods, providing (together with this paper)
a complete solution for 1-monoidal abelian categories.
  Our approach to Deligne conjecture is divided into two parts. The first part,
completed in the present paper, provides a construction of a weak Leinster
$(n,1)$-algebra over $k$, out of an $n$-fold monoidal $k$-linear abelian
category (provided the compatibility and non-degeneracy condition are
fulfilled). The second part (still open for $n>1$) is a passage from weak
Leinster $(n,1)$-algebras to $C(E_{n+1},k)$-algebras.
  As an application, we prove that the Gerstenhaber-Schack complex of a Hopf
algebra over a field $k$ of characteristic 0 admits a structure of a weak
Leinster (2,1)-algebra over $k$ extending the Yoneda structure. It relies on
our earlier construction [Sh1] of a 2-fold monoidal structure on the abelian
category of tetramodules over a bialgebra.


title: Nonlinear Spectral Singularities for Localized Nonlinearities

abstract:
  We introduce a notion of spectral singularity that applies for a general
class of nonlinear Schreodinger operators involving a confined nonlinearity.
The presence of the nonlinearity does not break the parity-reflection symmetry
of spectral singularities but makes them amplitude-dependent. Nonlinear
spectral singularities are, therefore, associated with a resonance effect that
produces amplified waves with a specific amplitude-wavelength profile. We
explore the consequences of this phenomenon for a complex delta-function
potential that is subject to a general confined nonlinearity.


title:
Performance tests of an AGIPD 0.4 assembly at the beamline P10 of PETRA
  III

abstract:
  The Adaptive Gain Integrating Pixel Detector (AGIPD) is a novel detector
system, currently under development by a collaboration of DESY, the Paul
Scherrer Institute in Switzerland, the University of Hamburg and the University
of Bonn, and is primarily designed for use at the European XFEL. To verify key
features of this detector, an AGIPD 0.4 test chip assembly was tested at the
P10 beamline of the PETRA III synchrotron at DESY. The test chip successfully
imaged both the direct synchrotron beam and single 7.05 keV photons at the same
time, demonstrating the large dynamic range required for XFEL experiments.
X-ray scattering measurements from a test sample agree with standard
measurements and show the chip's capability of observing dynamics at the
microsecond time scale.


title: On the Origins of Hierarchy in Complex Networks

abstract:
  Hierarchy seems to pervade complexity in both living and artificial systems.
Despite its relevance, no general theory that captures all features of
hierarchy and its origins has been proposed yet. Here we present a formal
approach resulting from the convergence of theoretical morphology and network
theory that allows constructing a 3D morphospace of hierarchies and hence
comparing the hierarchical organization of ecological, cellular, technological
and social networks. Embedded within large voids in the morphospace of all
possible hierarchies, four major groups are identified. Two of them match the
expected from random networks with similar connectivity, thus suggesting that
non-adaptive factors are at work. Ecological and gene networks define the other
two, indicating that their topological order is the result of functional
constraints. These results are consistent with an exploration of the
morphospace using in silico evolved networks.


title:
Initial coefficient bounds for certain classes of Meromorphic
  bi-univalent functions

abstract:
  In this paper we extend the concept of bi-univalent to the class of
meromorphic functions. We propose to investigate the coefficient estimates for
two classes of meromorphic bi-univalent functions. Also, we find estimates on
the coefficients |b0| and |b1| for functions in these new classes. Some
interesting remarks and applications of the results presented here are also
discussed.


title: Coarsening in 2D slabs

abstract:
  We study coarsening; that is, the zero-temperature limit of Glauber dynamics
in the standard Ising model on slabs S_k = Z^2 x {0, ..., k-1} of all
thicknesses k \geq 2 (with free and periodic boundary conditions in the third
coordinate). We show that with free boundary conditions, for k \geq 3, some
sites fixate for large times and some do not, whereas for k=2, all sites
fixate. With periodic boundary conditions, for k \geq 4, some sites fixate and
others do not, while for k=2 and 3, all sites fixate.


title: Monte-Carlo utility estimates for Bayesian reinforcement learning

abstract:
  This paper introduces a set of algorithms for Monte-Carlo Bayesian
reinforcement learning. Firstly, Monte-Carlo estimation of upper bounds on the
Bayes-optimal value function is employed to construct an optimistic policy.
Secondly, gradient-based algorithms for approximate upper and lower bounds are
introduced. Finally, we introduce a new class of gradient algorithms for
Bayesian Bellman error minimisation. We theoretically show that the gradient
methods are sound. Experimentally, we demonstrate the superiority of the upper
bound method in terms of reward obtained. However, we also show that the
Bayesian Bellman error method is a close second, despite its significant
computational simplicity.


title: What Makes a Computation Unconventional?

abstract:
  A coherent mathematical overview of computation and its generalisations is
described. This conceptual framework is sufficient to comfortably host a wide
range of contemporary thinking on embodied computation and its models.


title:
AC-field-induced Polarization for Uncharged Colloids in Salt Solution: A
  Dissipative Particle Dynamics Simulation

abstract:
  We study the response of a spherical colloid under alternating electric
fields (AC-fields) by mesoscopic simulation method, accounting in full for
hydrodynamic and electrostatic interactions. We focus on a special case of
uncharged colloids. The main polarization mechanism is the
"volume-polarization", where ionic currents are deflected by the core of the
uncharged colloid. Specifically, we compute the polarizability of a single
colloid and systematically investigate the effect of AC field frequency and
salt concentration. The simulation results are compared with predictions from
classical Maxwell-Wagner theory and electrokinetic theory.


title: Cosmological Perturbation Theory

abstract:
  A short pedagogical overview of cosmological perturbation theory, following
the lectures given during the brazilian school of cosmology held in August
2012. Topics treated are:
  I. The background
  II. SVT decomposition and the gauge issue.
  III. The example of the tensor modes.
  IV. Density fluctuations, transfer function and power spectrum.
  V. Initial condition theory: quantum vacuum fluctuations.


title:
Magnetic control of spin-orbit fields: a first-principles study of
  Fe/GaAs junctions

abstract:
  The microscopic structure of spin-orbit fields for the technologically
important Fe/GaAs interface is uncovered from first principles. A symmetry
based method allows to obtain the spin-orbit fields---both their magnitude and
orientation---for a generic Bloch state, from the electronic band structure for
any in-plane magnetization orientation. It is demonstrated that the spin-orbit
fields depend not only on the electric field across the interface, but also
surprisingly strongly on the Fe magnetization orientation, opening prospects
for their magnetic control. These results give important clues in searching for
spin-orbit transport and optical phenomena in ferromagnetic/nonmagnetic
systems.


title:
Large-scale first principles configuration interaction calculations of
  optical absorption in aluminum clusters

abstract:
  We report the linear optical absorption spectra of aluminum clusters Al$_{n}$
(n=2--5) involving valence transitions, computed using the large-scale
all-electron configuration interaction (CI) methodology. Several low-lying
isomers of each cluster were considered, and their geometries were optimized at
the coupled-cluster singles doubles (CCSD) level of theory. With these
optimized ground-state geometries, excited states of different clusters were
computed using the multi-reference singles-doubles configuration-interaction
(MRSDCI) approach, which includes electron correlation effects at a
sophisticated level. These CI wave functions were used to compute the
transition dipole matrix elements connecting the ground and various excited
states of different clusters, and thus their photoabsorption spectra. The
convergence of our results with respect to the basis sets, and the size of the
CI expansion, was carefully examined. Our results were found to be
significantly different as compared to those obtained using time-dependent
density functional theory (TDDFT) [Deshpande \textit{et al. Phys. Rev. B},
2003, \textbf{68}, 035428]. When compared to available experimental data for
the isomers of Al$_{2}$ and Al$_{3}$, our results are in very good agreement as
far as important peak positions are concerned.
  The contribution of configurations to many body wavefunction of various
excited states suggests that in most cases optical excitations involved are
collective, and plasmonic in nature.


title:
126 GeV Higgs and ATLAS bound on the lightest graviton mass in
  Randall-Sundrum model

abstract:
  In the search for extra dimension through dilepton events in 7-TeV
proton-proton collision, the ATLAS detector at LHC has set stringent lower
bound on the mass of the Randall-Sundrum (RS) lightest graviton Kaluza-Klein
(KK) mode. Considering that the Randall-Sundrum model undertakes to resolve the
well-known gauge hierarchy/fine tuning problem to restrict the Higgs mass
within the estimated $\sim 126$ GeV against large radiative correction upto the
cut-off of the model, we explore the allowed parameter space within which the
RS model can be trusted. We show that the consistency of the model with ATLAS
results constrains the cut-off of the theory which is atleast two order lower
than the Planck/Quantum gravity scale implying the possible existence of a new
Physics at this lower scale.


title:
Portfolio Optimization under Partial Information with Expert Opinions: a
  Dynamic Programming Approach

abstract:
  This paper investigates optimal portfolio strategies in a market where the
drift is driven by an unobserved Markov chain. Information on the state of this
chain is obtained from stock prices and expert opinions in the form of signals
at random discrete time points. As in Frey et al. (2012), Int. J. Theor. Appl.
Finance, 15, No. 1, we use stochastic filtering to transform the original
problem into an optimization problem under full information where the state
variable is the filter for the Markov chain. The dynamic programming equation
for this problem is studied with viscosity-solution techniques and with
regularization arguments.


title:
A local constant-factor approximation algorithm for MDS problem in
  anonymous network

abstract:
  In research on distributed local algorithms it is commonly assumed that each
vertex has a unique identifier in the entire graph. However, it turns out that
in case of certain classes of graphs (for example not lift-closed bounded
degree graphs) identifiers are unnecessary and only a port ordering is needed.
One of the open issues was whether identifiers are essential in planar graphs.
In this paper, we answer this question and we propose an algorithm which
returns constant approximation of the MDS problem in CONGEST model. The
algorithm doesn't use any additional information about the structure of the
graph and the nodes don't have unique identifiers. We hope that this paper will
be very helpful as a hint for further comparisons of the unique identifier
model and the model with only a port numbering in other classes of graphs.


title: Quantized Abelian principal connections on Lorentzian manifolds

abstract:
  We construct a covariant functor from a category of Abelian principal bundles
over globally hyperbolic spacetimes to a category of *-algebras that describes
quantized principal connections. We work within an appropriate differential
geometric setting by using the bundle of connections and we study the full
gauge group, namely the group of vertical principal bundle automorphisms.
Properties of our functor are investigated in detail and, similar to earlier
works, it is found that due to topological obstructions the locality property
of locally covariant quantum field theory is violated. Furthermore, we prove
that, for Abelian structure groups containing a nontrivial compact factor, the
gauge invariant Borchers-Uhlmann algebra of the vector dual of the bundle of
connections is not separating on gauge equivalence classes of principal
connections. We introduce a topological generalization of the concept of
locally covariant quantum fields. As examples, we construct for the category of
principal U(1)-bundles two natural transformations from singular homology
functors to the quantum field theory functor that can be interpreted as the
Chern class and the electric charge. In this case we also prove that the
electric charges can be consistently set to zero, which yields another quantum
field theory functor that satisfies all axioms of locally covariant quantum
field theory.


title: Nonlinear coherent states for the Susskind-Glogower operators

abstract:
  We construct nonlinear coherent states for the Susskind-Glogower operators by
the application of the displacement operator on the vacuum state. We also
construct nonlinear coherent states as eigenfunctions of a Hamiltonian
constructed with the Susskind-Glogower operators. We generalize the solution of
the eigen- function problem to an arbitrary |mi initial condition. To analyze
the obtained results, we plot the Husimi Q function, the photon number
probability distribution and the Mandel Q-parameter. For both cases, we find
that the constructed states exhibit interesting nonclassical features, such as
amplitude squeezing and quantum interferences due to a self-splitting into two
coherent-like states. Additionally, we show that non- linear coherent states
may be modeled by propagating light in semi-infinite arrays of optical fibers.


title:
Refinement revisited with connections to Bayes error, conditional
  entropy and calibrated classifiers

abstract:
  The concept of refinement from probability elicitation is considered for
proper scoring rules. Taking directions from the axioms of probability,
refinement is further clarified using a Hilbert space interpretation and
reformulated into the underlying data distribution setting where connections to
maximal marginal diversity and conditional entropy are considered and used to
derive measures that provide arbitrarily tight bounds on the Bayes error.
Refinement is also reformulated into the classifier output setting and its
connections to calibrated classifiers and proper margin losses are established.


title:
Local quantum criticality out of equilibrium - effective temperatures
  and scaling in the steady state regime

abstract:
  We study the out of equilibrium steady state properties of the
Bose-Fermi-Kondo model, describing a local magnetic moment coupled to two
ferromagnetic leads that support bosonic (magnons) and fermionic (Stoner
continuum electrons) low energy excitations. This model describes the
destruction of the Kondo effect as the coupling to the bosons is increased. Its
phase diagram comprises three non-trivial fixed points. Using a dynamical
large-$N$approach on the Keldysh contour, we study two different
non-equilibrium setups: (a) a finite bias voltage and (b) a finite temperature
gradient, imposed across the leads. The scaling behavior of the charge and
energy currents is identified and characterized for all fixed points. We report
the existence of a fixed-point-dependent effective temperature, defined though
the fluctuation dissipation relations of the local spin-susceptibility in the
scaling regime, which permits to recover the equilibrium behavior of both
dynamical and static spin susceptibilities.


title: Shell interactions for Dirac operators

abstract:
  The self-adjointness of $H+V$ is studied, where $H=-i\alpha\cdot\nabla
+m\beta$ is the free Dirac operator in $\R^3$ and $V$ is a measure-valued
potential. The potentials $V$ under consideration are given by singular
measures with respect to the Lebesgue measure, with special attention to
surface measures of bounded regular domains. The existence of non-trivial
eigenfunctions with zero eigenvalue naturally appears in our approach, which is
based on well known estimates for the trace operator defined on classical
Sobolev spaces and some algebraic identities of the Cauchy operator associated
to $H$.


title: Resonant states and pseudospin symmetry in the Dirac Morse potential

abstract:
  The complex scaling method is applied to study the resonances of a Dirac
particle in a Morse potential. The applicability of the method is demonstrated
with the results compared with the available data. It is shown that the present
calculations in the nonrelativistic limit are in excellent agreement with the
nonrelativistic calculations. Further, the dependence of the resonant
parameters on the shape of the potential is checked, and the unusual
sensitivity to the potential parameters is revealed. By comparing the energies
and widths of the pseudospin doublets, well pseudospin symmetry is discovered
in the present model. The relationship between the pseudospin symmetry and the
shape of the potential is investigated by changing the Morse potential shaped
by the dissociation energy, the equilibrium intermolecular distance, and the
positive number controlling the decay length of the potential.


title: Dynamics of iterated function systems on the circle close to rotations

abstract:
  We study the dynamics of iteration function systems generated by a pair of
circle diffeomorphisms close to rotations in the $C^{1+\mathrm{bv}}$-topology.
We characterize the obstruction to minimality and describe the limit set. In
particular, there are no invariant minimal Cantor sets, which can be seen as a
Denjoy/Duminy type theorem for iterated systems on the circle.


title:
Resonances in dissipative optomechanics with nanoparticles: Sorting,
  speed rectification and transverse cooling

abstract:
  The interaction between dielectric particles and a laser-driven optical
cavity gives rise to both conservative and dissipative dynamics, which can be
used to levitate, trap and cool nanoparticles. We analytically and numerically
study a two-mode setup in which the optical potentials along the cavity axis
cancel, so that the resulting dynamics is almost purely dissipative. For
appropriate detunings of the laser-drives, this dissipative optomechanical
dynamics can be used to sort particles according to their size, to rectify
their velocities and to enhance transverse cooling.


title:
Challenges for the Adaptive Gain Integrating Pixel Detector (AGIPD)
  design due to the high intensity photon radiation environment at the European
  XFEL

abstract:
  The European X-ray Free Electron Laser (XFEL) is a new research facility
currently under construction in Hamburg, Germany. With a pulse length of less
than 100 fs and an extremely high luminosity of 27000 flashes per second the
European XFEL will have a unique time structure that demands the development of
new detectors tailored to the requirements imposed by the experiments while
complying with the machine specific operation parameters. The Adaptive Gain
Integrating Pixel Detector (AGIPD) is one response to the need for large 2D
detectors, able to cope with the 4.5 MHz frame rate, as well as with the high
dynamic range needed by XFEL experiments ranging from single photons to more
than 10$^4$ 12 keV photons per pixel per pulse. In addition it has to withstand
doses of up to 1 GGy over three years.


title:
Adaptive discontinuous Galerkin approximations to fourth order parabolic
  problems

abstract:
  An adaptive algorithm, based on residual type a posteriori indicators of
errors measured in $L^{\infty}(L^2)$ and $L^2(L^2)$ norms, for a numerical
scheme consisting of implicit Euler method in time and discontinuous Galerkin
method in space for linear parabolic fourth order problems is presented. The a
posteriori analysis is performed for convex domains in two and three space
dimensions for local spatial polynomial degrees $r\ge 2$. The a posteriori
estimates are then used within an adaptive algorithm, highlighting their
relevance in practical computations, which results into substantial reduction
of computational effort.


title:
The geometry of quadratic polynomial differential systems with a finite
  and an infinite saddle-node (A,B)

abstract:
  The goal is to make a global study of the family QsnSN of all real quadratic
polynomial differential systems which have a finite semi-elemental saddle-node
and an infinite saddle-node formed by the collision of two infinite singular
points. This family can be divided into three different subfamilies, all of
them with the finite saddle-node in the origin of the plane with the
eigenvectors on the axes and (A) with the infinite saddle-node in the
horizontal axis, (B) with the infinite saddle-node in the vertical axis and (C)
with the infinite saddle-node in the bisector of the first and third quadrants.
These three subfamilies modulo the action of the affine group and time
homotheties are three-dimensional and we give their bifurcation diagram with
respect to a normal form, in the three-dimensional real space of the parameters
of these forms. In this paper we provide the complete study of the geometry of
the first two families, (A) and (B). The bifurcation diagram for the subfamily
(A) yields 29 phase portraits for systems in QsnSN(A) counting phase portraits
with and without limit cycles, while the bifurcation diagram for the subfamily
(B) yields 16 phase portraits for systems in QsnSN(B) under the same
conditions. Case (C) will yield quite more cases and will have an independent
paper in short. Algebraic invariants are used to construct the bifurcation set.
The phase portraits are represented on the Poincar\'e disk. The bifurcation set
of QsnSN(A) is not only algebraic due to the presence of a surface found
numerically. All points in this surface correspond to connections of
separatrices.


title: On the Entropy of a Two Step Random Fibonacci Substitution

abstract:
  We consider a random generalisation of the classical Fibonacci substitution.
The substitution we consider is defined as the rule mapping $\mathtt{a}\mapsto
\mathtt{baa}$ and $\mathtt{b} \mapsto \mathtt{ab}$ with probability $p$ and
$\mathtt{b} \mapsto \mathtt{ba}$ with probability $1-p$ for $0<p<1$ and where
the random rule is applied each time it acts on a $\mathtt{b}$. We show that
the topological entropy of this object is given by the growth rate of the set
of inflated random Fibonacci words, and we exactly calculate its value.


title: Initial coefficient bounds for a general class of bi-univalent functions

abstract:
  Inspired by the recent works of Srivastava et al. (HMS-AKM-PG), Frasin and
Aouf (BAF-MKA) and others
(Ali-Ravi-Ma-Mina-class,Caglar-Orhan,Goyal-Goswami,Xu-HMS-AML,Xu-HMS-AMC), we
propose to investigate the coefficient estimates for a general class of
analytic and bi-univalent functions. Also, we obtain estimates on the
coefficients |a2| and |a3| for functions in this new class. Some interesting
remarks, corollaries and applications of the results presented here are also
discussed.


title: Random packing of spheres in Menger sponge

abstract:
  Random packing of spheres inside fractal collectors of dimension 2 < d < 3 is
studied numerically using Random Sequential Adsorption (RSA) algorithm. The
paper focuses mainly on the measurement of random packing saturation limit.
Additionally, scaling properties of density autocorrelations in the obtained
packing are analyzed. The RSA kinetics coefficients are also measured. Obtained
results allow to test phenomenological relation between random packing
saturation density and collector dimension. Additionally, performed simulations
together with previously obtained results confirm that, in general, the known
dimensional relations are obeyed by systems having non-integer dimension, at
least for d < 3.


title: Two-wire Terahertz Fibers with Porous Dielectric Support

abstract:
  A novel plasmonic THz fiber is described that features two metallic wires
that are held in place by the porous dielectric cladding functioning as a
mechanical support. This design is more convenient for practical applications
than a classic two metal wire THz waveguide as it allows direct manipulations
of the fiber without the risk of perturbing its core-guided mode. Not
surprisingly, optical properties of such fibers are inferior to those of a
classic two-wire waveguide due to the presence of lossy dielectric near an
inter-wire gap. At the same time, composite fibers outperform porous fibers of
the same geometry both in bandwidth of operation and in lower dispersion.
Finally, by increasing cladding porosity one can consistently improve optical
properties of the composite fibers.


title:
Infinite-dimensional Bayesian filtering for detection of quasi-periodic
  phenomena in spatio-temporal data

abstract:
  This paper introduces a spatio-temporal resonator model and an inference
method for detection and estimation of nearly periodic temporal phenomena in
spatio-temporal data. The model is derived as a spatial extension of a
stochastic harmonic resonator model, which can be formulated in terms of a
stochastic differential equation (SDE). The spatial structure is included by
introducing linear operators, which affect both the oscillations and damping,
and by choosing the appropriate spatial covariance structure of the driving
time-white noise process. With the choice of the linear operators as partial
differential operators, the resonator model becomes a stochastic partial
differential equation (SPDE), which is compatible with infinite-dimensional
Kalman filtering. The resulting infinite-dimensional Kalman filtering problem
allows for a computationally efficient solution as the computational cost
scales linearly with measurements in the temporal dimension. This framework is
applied to weather prediction and to physiological noise elimination in fMRI
brain data.


title:
Chemical Precipitation Synthesis of Ferric Chloride Doped Zinc Sulphide
  Nanoparticles and Their Characterization Studies

abstract:
  Nanoparticles of Ferric Chloride doped ZnS has been synthesized by simple
chemical precipitation method and characterized by XRD, SEM, UV-Vis analysis,
Differential Thermal Analysis, Thermo Gravimetric Analysis and Differential
Scanning Calorimetry. XRD patterns of the samples reveal particle size,
specific surface area and the formation of cubic structure. The SEM images show
that the cauliflower likes structure. Optical band gap values have been
obtained from UV-Vis absorption spectra. It has also been found that energy
band gap (Eg) increases with the increase in molar concentration of reactant
solution. Thermal analysis measurement of the prepared sample shows that the
thermal stability of pure ZnS is decreased due to increase in Ferric Chloride
concentration. Undoped ZnS is more thermal stable when compared to FeCl3 doped
ZnS.


title: Infrared spectroscopy of small-molecule endofullerenes

abstract:
  Hydrogen is one of the few molecules which has been incarcerated in the
molecular cage of C$_{60}$ and forms endohedral supramolecular complex
H$_2$@C$_{60}$. In this confinement hydrogen acquires new properties. Its
translational motion becomes quantized and is correlated with its rotations. We
applied infrared spectroscopy to study the dynamics of hydrogen isotopologs
H$_2$, D$_2$ and HD incarcerated in C$_{60}$. The translational and rotational
modes appear as side bands to the hydrogen vibrational mode in the mid infrared
part of the absorption spectrum. Because of the large mass difference of
hydrogen and C$_{60}$ and the high symmetry of C$_{60}$ the problem is
identical to a problem of a vibrating rotor moving in a three-dimensional
spherical potential. The translational motion within the C$_{60}$ cavity breaks
the inversion symmetry and induces optical activity of H$_2$. We derive
potential, rotational, vibrational and dipole moment parameters from the
analysis of the infrared absorption spectra. Our results were used to derive
the parameters of a pairwise additive five-dimensional potential energy surface
for H$_2$@C$_{60}$. The same parameters were used to predict H$_2$ energies
inside C$_{70}$[Xu et al., J. Chem. Phys., {\bf 130}, 224306 (2009)]. We
compare the predicted energies and the low temperature infrared absorption
spectra of H$_2$@C$_{70}$.


title:
Photon- and phonon-assisted tunneling in the three-dimensional charge
  stability diagram of a triple quantum dot array

abstract:
  We report both photon- and phonon-assisted tunneling transitions in a linear
array of three quantum dots, which can only be understood by considering the
full three-dimensionality of the charge stability diagram. Such tunneling
transitions potentially contribute to leakage of qubits defined in this system.
A detailed understanding of these transitions is important as they become more
abundant and complex to analyze as quantum dot arrays are scaled up.


title: The Reach of INO for Atmospheric Neutrino Oscillation Parameters

abstract:
  The India-based Neutrino Observatory (INO) will host a 50 kt magnetized iron
calorimeter (ICAL@INO) for the study of atmospheric neutrinos. Using the
detector resolutions and efficiencies obtained by the INO collaboration from a
full-detector GEANT4-based simulation, we determine the reach of this
experiment for the measurement of the atmospheric neutrino mixing parameters
($\sin^2 \theta_{23}$ and $|\Delta m_{32}^2 |$). We also explore the
sensitivity of this experiment to the deviation of $\theta_{23}$ from maximal
mixing, and its octant.


title:
Ultrasmall divergence of laser-driven ion beams from nanometer thick
  foils

abstract:
  We report on experimental studies of divergence of proton beams from
nanometer thick diamond-like carbon (DLC) foils irradiated by an intense laser
with high contrast. Proton beams with extremely small divergence (half angle)
of 2 degree are observed in addition with a remarkably well-collimated feature
over the whole energy range, showing one order of magnitude reduction of the
divergence angle in comparison to the results from micrometer thick targets. We
demonstrate that this reduction arises from a steep longitudinal electron
density gradient and an exponentially decaying transverse profile at the rear
side of the ultrathin foils. Agreements are found both in an analytical model
and in particle-in-cell simulations. Those novel features make nm foils an
attractive alternative for high flux experiments relevant for fundamental
research in nuclear and warm dense matter physics.


title: Rank-unimodality of Young's lattice via explicit chain decomposition

abstract:
  Young's lattice $L(m,n)$ consists of partitions having $m$ parts of size at
most $n$, ordered by inclusion of the corresponding Ferrers diagrams. K. O'Hara
gave the first constructive proof of the unimodality of the Gaussian
polynomials by expressing the underlying ranked set of $L(m,n)$ as a disjoint
union of products of centered rank-unimodal subsets. We construct a finer
decomposition which is compatible with the partial order on Young's lattice, at
the cost of replacing the cartesian product with a more general poset
extension. As a corollary, we obtain an explicit chain decomposition which
exhibits the rank-unimodality of $L(m,n)$. Moreover, this set of chains is
closed under the natural rank-flipping involution given by taking complements
of Ferrers diagrams.


title: Graded Geometric Structures Underlying F-Theory Related Defect Theories

abstract:
  In the context of F-theory, we study the related eight dimensional
super-Yang-Mills theory and reveal the underlying supersymmetric quantum
mechanics algebra that the fermionic fields localized on the corresponding
defect theory are related to. Particularly, the localized fermionic fields
constitute a graded vector space, and in turn this graded space enriches the
geometric structures that can be built on the initial eight-dimensional space.
We construct the implied composite fibre bundles, which include the graded
affine vector space and demonstrate that the composite sections of this fibre
bundle are in one-to-one correspondence to the sections of the square root of
the canonical bundle corresponding to the submanifold on which the zero modes
are localized.


title:
Age -- Metallicity relation in the MCs clusters (Based on observations
  made with the Danish 1.54 m and ESO 3.6m Telescopes at La Silla Observatory,
  Chile)

abstract:
  Aims: To investigate a possible dependence between age and metallicity in the
Magellanic Clouds (MCs) from a study of small open star clusters, using
Str\"{o}mgren photometry. Our goal is to trace evidence of an age metallicity
relation (AMR) and correlate it with the mutual interactions of the two MCs.
Our aim is also to correlate the AMR with the spatial distribution of the
clusters. In the Large Magellanic Cloud (LMC), the majority of the selected
clusters are young (up to 1 Gyr) and our aim is to search for an AMR at this
epoch which has not been much studied. Methods: We report on results for 15 LMC
and 8 Small Magellanic Cloud (SMC) clusters, scattered all over the area of
these galaxies, to cover a wide spatial distribution and metallicity range. The
selected LMC clusters were observed with the 1.54m Danish Telescope in Chile,
using the Danish Faint Object Spectrograph and Camera (DFOSC) with a single
2kx2k CCD, whereas the SMC clusters were observed with the ESO 3.6m Telescope
also in Chile with the ESO Faint Object Spectrograph and Camera (EFOSC). The
obtained frames were analysed with the conventional DAOPHOT and IRAF software.
We used Str\"{o}mgren filters in order to achieve reliable metallicities from
photometry. Isochrone fitting was used in order to determine the ages and
metallicities. Results: The AMR for the LMC displays a metallicity gradient,
with higher metallicities for the younger ages. The AMR for LMC-SMC star
clusters shows a possible jump in metallicity and a considerable increase at
about 6x10^8 yr. It is possible that this is connected to the latest LMC-SMC
interaction. The AMR for the LMC also displays a metallicity gradient with
distance from the centre. The metallicities in SMC are lower, as expected for a
metal poor host galaxy.


title: Nanoscale resolution immersion scanning thermal microscopy

abstract:
  Nanoscale thermal properties are becoming of extreme importance for modern
electronic circuits that dissipate increasing power on the length scale of few
tens of nanometers, and for chemical and physical properties sensors and
biosensors using nanoscale sized features. While Scanning Thermal Microscopy
(SThM) is known for its ability to probe thermal properties and heat generation
with nanoscale resolution, until today it was perceived impossible to use it in
the liquid environment due to dominating direct heat exchange between
microfabricated thermal probe and surrounding liquid that would deteriorate
spatial resolution. Nonetheless, our theoretical analysis of SThM in liquids
showed that for certain design of SThM probe with resistive heater located near
the probe tip, their thermal signal is only moderately affected, by less than
half on immersion in a dodecane environment. More significantly, its spatial
resolution, surprisingly, would remain practically unaffected, and the thermal
contact between the tip apex and the studied sample would be beneficially
improved. Our experimental trials of such immersion SThM, or iSThM, were fully
successful and here we report for the first time nanoscale SThM measurements of
thermal conductivity of Ultra Large Scale Integration polymerceramic metal
interconnects with the spatial thermal resolution down to 50 nm. Further
studies of heat transport in nanoscale graphite flakes in iSThM suggested, in
particular, that highly anisotropic thermal conductivity in graphene layers may
play significant role in the nanoscale thermal transport in liquid environment.
New iSThM opens a wide range of applications from noncontact measurements of
thermal transport in semiconductor devices to exploring graphene energy
storage, catalytic reactions and heat generation in biological systems.

categories: physics.ins-det cond-mat.mes-hall cond-mat.mtrl-sci physics.med-ph


title:
Theoretical framework to analyze searches for hidden light gauge bosons
  in electron scattering fixed target experiments

abstract:
  Motivated by anomalies in cosmic ray observations and by attempts to solve
questions of the Standad Model of particle physics like the (g-2)_mu
discrepancy, U(1) extensions of the Standard Model have been proposed in recent
years. Such U(1) extensions allow for the interaction of Dark Matter by
exchange of a photon-like massive force carrier \gamma' not included in the
Standard Model. In order to search for \gamma' bosons various experimental
programs have been started. One approach is the dedicated search at
fixed-target experiments at modest energies as performed at MAMI or at the
Jefferson Lab. In these experiments the process e(A,Z)->e(A,Z)l^+l^- is
investigated and a search for a very narrow resonance in the invariant mass
distribution of the l^+l^- pair is performed. In this work we analyze this
process in terms of signal and background in order to describe existing data
obtained by the A1 experiment at MAMI with the aim to give accurate predictions
for exclusion limits in the \gamma' parameter space. We present a detailed
theoretical analysis of the cross sections entering in the description of such
processes.


title: Shock waves in dispersive Eulerian fluids

abstract:
  The long time behavior of an initial step resulting in a dispersive shock
wave (DSW) for the one-dimensional isentropic Euler equations regularized by
generic, third order dispersion is considered by use of Whitham averaging.
Under modest assumptions, the jump conditions (DSW locus and speeds) for
admissible, weak DSWs are characterized and found to depend only upon the sign
of dispersion (convex or concave) and a general pressure law. Two mechanisms
leading to the breakdown of this simple wave DSW theory for sufficiently large
jumps are identified: a change in the sign of dispersion, leading to gradient
catastrophe in the modulation equations, and the loss of genuine nonlinearity
in the modulation equations. Large amplitude DSWs are constructed for several
particular dispersive fluids with differing pressure laws modeled by the
generalized nonlinear Schrodinger equation. These include superfluids
(Bose-Einstein condensates and ultracold Fermions) and "optical fluids".
Estimates of breaking times for smooth initial data and the long time behavior
of the shock tube problem are presented. Numerical simulations compare
favorably with the asymptotic results in the weak to moderate amplitude
regimes. Deviations in the large amplitude regime are identified with breakdown
of the simple wave DSW theory.


title:
Robust Smoothing for Estimating Optical Phase Varying as a Continuous
  Resonant Process

abstract:
  Continuous phase estimation is known to be superior in accuracy as compared
to static estimation. The estimation process is, however, desired to be made
robust to uncertainties in the underlying parameters. Here, homodyne phase
estimation of coherent and squeezed states of light, evolving continuously
under the influence of a second-order resonant noise process, are made robust
to parameter uncertainties using a robust fixed-interval smoother, designed for
uncertain systems satisfying a certain integral quadratic constraint. We
observe that such a robust smoother provides improved worst-case performance
over the optimal smoother and also performs better than a robust filter for the
uncertain system.


title:
Estimation of Persistence Lengths of Semiflexible Polymers: Insight from
  Simulations

abstract:
  The persistence length of macromolecules is one of their basic
characteristics, describing their intrinsic local stiffness. However, it is
difficult to extract this length from physical properties of the polymers,
different recipes may give answers that disagree with each other. Monte Carlo
simulations are used to elucidate this problem, giving a comparative discussion
of two lattice models, the self-avoiding walk model extended by a bond bending
energy, and bottle-brush polymers described by the bond fluctuation model. The
conditions are discussed under which a description of such macromolecules by
Kratky-Porod worm-like chains holds, and the question to what extent the
persistence length depends on external conditions (such as solvent quality) is
considered. The scattering function of semiflexible polymers is discussed in
detail, a comparison to various analytic treatments is given, and an outlook to
experimental work is presented.


title:
High Curie temperatures at low compensation in the ferromagnetic
  semiconductor (Ga,Mn)As

abstract:
  We investigate the relationship between the Curie temperature TC and the
carrier density p in the ferromagnetic semiconductor (Ga,Mn)As. Carrier
densities are extracted from analysis of the Hall resistance at low
temperatures and high magnetic fields. Results are found to be consistent with
ion channeling measurements when performed on the same samples. We find that
both TC and the electrical conductivity increase monotonically with increasing
p, and take their largest values when p is comparable to the concentration of
substitutional Mn acceptors. This is inconsistent with models in which the
Fermi level is located within a narrow isolated impurity band.


title:
Optimization of the parity-check matrix density in QC-LDPC code-based
  McEliece cryptosystems

abstract:
  Low-density parity-check (LDPC) codes are one of the most promising families
of codes to replace the Goppa codes originally used in the McEliece
cryptosystem. In fact, it has been shown that by using quasi-cyclic low-density
parity-check (QC-LDPC) codes in this system, drastic reductions in the public
key size can be achieved, while maintaining fixed security levels. Recently,
some proposals have appeared in the literature using codes with denser
parity-check matrices, named moderate-density parity-check (MDPC) codes.
However, the density of the parity-check matrices to be used in QC-LDPC
code-based variants of the McEliece cryptosystem has never been optimized. This
paper aims at filling such gap, by proposing a procedure for selecting the
density of the private parity-check matrix, based on the security level and the
decryption complexity. We provide some examples of the system parameters
obtained through the proposed technique.


title:
On the Complexity of Maximum Clique Algorithms: usage of coloring
  heuristics leads to the 2^(n\5) algorithm running time lower bound

abstract:
  Maximum Clique Problem(MCP) is one of the 21 original NP--complete problems
enumerated by Karp in 1972. In recent years a large number of exact methods to
solve MCP have been appeared(Babel, Wood, Kumlander, Fahle, Li, Tomita and
etc). Most of them are branch and bound algorithms that use branching rule
introduced by Balas and Yu and based on coloring heuristics to establish an
upper bound on the clique number. They differ from each other primarily in
vertex preordering and vertex coloring methods. Current methods of worst case
running time analysis for branch and bound algorithms do not allow to provide
tight upper bounds. This motivates the study of lower bounds for such
algorithms. We prove 2^(n\5) lower bound for group of MCP algorithms based on
usage of coloring heuristics.


title:
On a family of binary completely transitive codes with growing covering
  radius

abstract:
  A new family of binary linear completely transitive (and, therefore,
completely regular) codes is constructed. The covering radius of these codes is
growing with the length of the code. In particular, for any integer r > 1,
there exist two codes with d=3, covering radius r and length 2r(4r-1) and
(2r+1)(4r+1), respectively. These new completely transitive codes induce, as
coset graphs, a family of distance-transitive graphs of growing diameter.


title:
Kerr Isolated Horizons in Ashtekar and Ashtekar-Barbero Connection
  Variables

abstract:
  The Ashtekar and Ashtekar-Barbero connection variable formulations of Kerr
isolated horizons are derived. Using a regular Kinnersley tetrad in
horizon-penetrating Kruskal-Szekeres-like coordinates, the spin coefficients of
Kerr geometry are determined by solving the first Maurer-Cartan equation of
structure. Isolated horizon conditions are imposed on the tetrad and the spin
coefficients. A transformation into an orthonormal tetrad frame that is fixed
in the time gauge is applied and explicit calculations of the spin connection,
the Ashtekar and Ashtekar-Barbero connections, and the corresponding curvatures
on the horizon 2-spheres are performed. Since the resulting Ashtekar-Barbero
curvature does not comply with the simple form of the horizon boundary
condition of Schwarzschild isolated horizons, i.e., on the horizon 2-spheres,
the Ashtekar-Barbero curvature is not proportional to the Plebanski 2-form,
which is required for an SU(2) Chern-Simons treatment of the gauge degrees of
freedom in the horizon boundary in the context of loop quantum gravity, a
general method to construct a new connection whose curvature satisfies such a
relation for Kerr isolated horizons is introduced. For the purpose of
illustration, this method is employed in the framework of slowly rotating Kerr
isolated horizons.


title: A Critical Look at the Standard Cosmological Picture

abstract:
  The discovery that the Universe is accelerating in its expansion has brought
the basic concept of cosmic expansion into question. An analysis of the
evolution of this concept suggests that the paradigm that was finally settled
into prior to that discovery was not the best option, as the observed
acceleration lends empirical support to an alternative which could incidentally
explain expansion in general. I suggest, then, that incomplete reasoning
regarding the nature of cosmic time in the derivation of the standard model is
the reason why the theory cannot coincide with this alternative concept.
Therefore, through an investigation of the theoretical and empirical facts
surrounding the nature of cosmic time, I argue that an enduring
three-dimensional cosmic present must necessarily be assumed in relativistic
cosmology---and in a stricter sense than it has been. Finally, I point to a
related result which could offer a better explanation of the empirically
constrained expansion rate.


title: Invariant theory for the elliptic normal quintic, II. The covering map

abstract:
  A genus one curve C of degree 5 is defined by the 4 x 4 Pfaffians of a 5 x 5
alternating matrix of linear forms on P^4. We prove a result characterising the
covariants for these models in terms of their restrictions to the family of
curves parametrised by the modular curve X(5). We then construct covariants
describing the covering map of degree 25 from C to its Jacobian and give a
practical algorithm for evaluating them.


title: Formation of the compact jets in the black hole GX 339-4

abstract:
  Galactic black hole binaries produce powerful outflows with emit over almost
the entire electromagnetic spectrum. Here, we report the first detection with
the Herschel observatory of a variable far-infrared source associated with the
compact jets of the black hole transient GX 339-4 during the decay of its
recent 2010-2011 outburst, after the transition to the hard state. We also
outline the results of very sensitive radio observations conducted with the
Australia Telescope Compact Array, along with a series of near-infrared,
optical (OIR) and X-ray observations, allowing for the first time the
re-ignition of the compact jets to be observed over a wide range of
wavelengths. The compact jets first turn on at radio frequencies with an
optically thin spectrum that later evolves to optically thick synchrotron
emission. An OIR reflare is observed about ten days after the onset of radio
and hard X-ray emission, likely reflecting the necessary time to build up
enough density, as well as to have acceleration (e.g. through shocks) along an
extended region in the jets. The Herschel measurements are consistent with an
extrapolation of the radio inverted power-law spectrum, but they highlight a
more complex radio to OIR spectral energy distribution for the jets.


title:
Multi-User Multi-Carrier Differential Chaos Shift Keying Communication
  System

abstract:
  In this paper, a multi user Multi-Carrier Differential Chaos Shift Keying
(MC-DCSK) modulation is presented. The system endeavors to provide a good
trade-off between robustness, energy efficiency and high data rate, while still
being simple. In this architecture of MC-DCSK system, for each user, chaotic
reference sequence is transmitted over a predefined subcarrier frequency.
Multiple modulated data streams are transmitted over the remaining subcarriers
allocated for each user. This transmitter structure saves energy and increases
the spectral efficiency of the conventional DCSK system.


title:
Distributed Intrusion Detection of Byzantine Attacks in Wireless
  Networks with Random Linear Network Coding

abstract:
  Network coding is an elegant technique where, instead of simply relaying the
packets of information they receive, the nodes of a network are allowed to
combine \emph{several} packets together for transmission and this technique can
be used to achieve the maximum possible information flow in a network and save
the needed number of packet transmissions. Moreover, in an energy-constraint
wireless network such as Wireless Sensor Network (a typical type of wireless ad
hoc network), applying network coding to reduce the number of wireless
transmissions can also prolong the life time of sensor nodes. Although applying
network coding in a wireless sensor network is obviously beneficial, due to the
operation that one transmitting information is actually combination of multiple
other information, it is possible that an error propagation may occur in the
network. This special characteristic also exposes network coding system to a
wide range of error attacks, especially Byzantine attacks. When some adversary
nodes generate error data in the network with network coding, those erroneous
information will be mixed at intermeidate nodes and thus corrupt all the
information reaching a destination. Recent research efforts have shown that
network coding can be combined with classical error control codes and
cryptography for secure communication or misbehavior detection. Nevertheless,
when it comes to Byzantine attacks, these results have limited effect. In fact,
unless we find out those adversary nodes and isolate them, network coding may
perform much worse than pure routing in the presence of malicious nodes. In
this paper, a distributed hierarchical algorithm based on random linear network
coding is developed to detect, locate and isolate malicious nodes.


title: Artifact Lifecycle Discovery

abstract:
  Artifact-centric modeling is a promising approach for modeling business
processes based on the so-called business artifacts - key entities driving the
company's operations and whose lifecycles define the overall business process.
While artifact-centric modeling shows significant advantages, the overwhelming
majority of existing process mining methods cannot be applied (directly) as
they are tailored to discover monolithic process models. This paper addresses
the problem by proposing a chain of methods that can be applied to discover
artifact lifecycle models in Guard-Stage-Milestone notation. We decompose the
problem in such a way that a wide range of existing (non-artifact-centric)
process discovery and analysis methods can be reused in a flexible manner. The
methods presented in this paper are implemented as software plug-ins for ProM,
a generic open-source framework and architecture for implementing process
mining tools.


title: Time dilation in relativistic two-particle interactions

abstract:
  We study the orbits of two interacting particles described by a fully
relativistic classical mechanical Hamiltonian. We use two sets of initial
conditions. In the first set (dynamics 1) the system's center of mass is at
rest. In the second set (dynamics 2) the center of mass evolves with velocity
V. If dynamics 1 is observed from a reference frame moving with velocity -V,
the principle of relativity requires that all observables must be identical to
those of dynamics 2 seen from the lab frame. Our numerical simulations
demonstrate that kinematic Lorentz space-time transformations fail to transform
particle observables between the two frames. This is explained as a result of
the inevitable interaction-dependence of the boost generator in the instant
form of relativistic dynamics. In spite of general inaccuracies of Lorentz
formulas, the orbital periods are correctly predicted by the Einstein's time
dilation factor for all interaction strengths.


title: Introduction aux m\'ethodes d'int\'egrale de chemin et applications

abstract:
  These lecture notes are based on a master course given at University Hassan
II - Agdal in spring 2012.


title:
Is magnetic reconnection the cause of supersonic upflows in granular
  cells ?

abstract:
  In a previous work, we reported on the discovery of supersonic magnetic
upflows on granular cells in data from the {\sc Sunrise}/IMaX instrument. In
the present work we investigate the physical origin of these events employing
data of the same instrument but with higher spectral sampling. By means of the
inversion of Stokes profiles we are able to recover the physical parameters
(temperature, magnetic field, line-of-sight velocity, etc) present in the solar
photosphere at the time of these events. The inversion is performed in a
Monte-Carlo-like fashion, that is, repeating it many times with different
initializations and retaining only the best result. We find that many of the
events are characterized by a reversal in the polarity of the magnetic field
along the vertical direction in the photosphere, accompanied by an enhancement
in the temperature and by supersonic line-of-sight velocities. In about half of
the studied events, large blue-shifted and red-shifted line-of-sight velocities
coexist above/below each other. These features can be explained in terms of
magnetic reconnection, where the energy stored in the magnetic field is
released in the form of kinetic and thermal energy when magnetic field lines of
opposite polarities coalesce. However, the agreement with magnetic reconnection
is not perfect and therefore, other possible physical mechanisms might also
play a role.


title:
Hybrid Mechanisms: Trading off Strategyproofness and Efficiency of
  Random Assignment Mechanisms

abstract:
  Severe impossibility results restrict the design of strategyproof random
assignment mechanisms, and trade-offs are necessary when aiming for more
demanding efficiency requirements, such as ordinal or rank efficiency. We
introduce hybrid mechanisms, which are convex combinations of two component
mechanisms. We give a set of conditions under which such hybrids facilitate a
non-degenerate trade-off between strategyproofness (in terms of partial
strategyproofness) and efficiency (in terms of dominance). This set of
conditions is tight in the sense that trade-offs may become degenerate if any
of the conditions are dropped. Moreover, we give an algorithm for the mechanism
designer's problem of determining a maximal mixing factor. Finally, we prove
that our construction can be applied to mix Random Serial Dictatorship with
Probabilistic Serial, as well as with the adaptive Boston mechanism, and we
illustrate the efficiency gains numerically.


title: Diffuse interface modelling of soluble surfactants in two-phase flow

abstract:
  Phase field models for two-phase flow with a surfactant soluble in possibly
both fluids are derived from balance equations and an energy inequality so that
thermodynamic consistency is guaranteed. Via a formal asymptotic analysis, they
are related to sharp interface models. Both cases of dynamic as well as
instantaneous adsorption are covered. Flexibility with respect to the choice of
bulk and surface free energies allows to realise various isotherms and
relations of state between surface tension and surfactant. Some numerical
simulations display the effectiveness of the presented approach.


title: Period Integrals and the Riemann-Hilbert Correspondence

abstract:
  A tautological system, introduced in [16][17], arises as a regular holonomic
system of partial differential equations that govern the period integrals of a
family of complete intersections in a complex manifold $X$, equipped with a
suitable Lie group action. A geometric formula for the holonomic rank of such a
system was conjectured in [4], and was verified for the case of projective
homogeneous space under an assumption. In this paper, we prove this conjecture
in full generality. By means of the Riemann-Hilbert correspondence and Fourier
transforms, we also generalize the rank formula to an arbitrary projective
manifold with a group action.


title: Localization of spherical varieties

abstract:
  We prove some fundamental structural results for spherical varieties in
arbitrary characteristic. In particular, we study Luna's two types of
localization and use it to analyze spherical roots, colors and their
interrelation. At the end, we propose a preliminary definition of a p-spherical
system.


title: Relativistic Mean-Field Models and Nuclear Matter Constraints

abstract:
  This work presents a preliminary study of 147 relativistic mean-field (RMF)
hadronic models used in the literature, regarding their behavior in the nuclear
matter regime. We analyze here different kinds of such models, namely: (i)
linear models, (ii) nonlinear \sigma^3+\sigma^4 models, (iii)
\sigma^3+\sigma^4+\omega^4 models, (iv) models containing mixing terms in the
fields \sigma and \omega, (v) density dependent models, and (vi) point-coupling
ones. In the finite range models, the attractive (repulsive) interaction is
described in the Lagrangian density by the \sigma (\omega) field. The isospin
dependence of the interaction is modeled by the \rho meson field. We submit
these sets of RMF models to eleven macroscopic (experimental and empirical)
constraints, used in a recent study in which 240 Skyrme parametrizations were
analyzed. Such constraints cover a wide range of properties related to
symmetric nuclear matter (SNM), pure neutron matter (PNM), and both SNM and
PNM.


title:
Simulating Star Clusters with the AMUSE Software Framework: I.
  Dependence of Cluster Lifetimes on Model Assumptions and Cluster Dissolution
  Modes

abstract:
  We perform a series of simulations of evolving star clusters using AMUSE (the
Astrophysical Multipurpose Software Environment), a new community-based
multi-physics simulation package, and compare our results to existing work.
These simulations model a star cluster beginning with a King model distribution
and a selection of power-law initial mass functions, and contain a tidal
cut-off. They are evolved using collisional stellar dynamics and include mass
loss due to stellar evolution. After determining that the differences between
AMUSE results and prior publications are understood, we explored the variation
in cluster lifetimes due to the random realization noise introduced by
transforming a King model to specific initial conditions. This random
realization noise can affect the lifetime of a simulated star cluster by up to
30%. Two modes of star cluster dissolution were identified: a mass evolution
curve that contains a run-away cluster dissolution with a sudden loss of mass,
and a dissolution mode that does not contain this feature. We refer to these
dissolution modes as "dynamical" and "relaxation" dominated respectively. For
Salpeter-like initial mass functions, we determined the boundary between these
two modes in terms of the dynamical and relaxation time scales.


title: On f-Symmetries of the Independence Polynomial

abstract:
  An independent set in a graph is a set of pairwise non-adjacent vertices, and
a(G) is the size of a maximum independent set in the graph G. If s_{k} is the
number of independent sets of cardinality k in G, then
I(G;x)=s_0+s_1*x+s_2*x^2+...+s_a*x^a,a=a(G), is called the independence
polynomial of G (I. Gutman and F. Harary, 1983). If s_{a-i}=f(i)*s_{i} holds
for every i, then I(G;x) is called f-symmetric (f-palindromic). If f(i)=1, then
I(G;x) is symmetric (palindromic). The corona of the graphs G and H is the
graph G*H obtained by joining each vertex of G to all the vertices of a copy of
H. In this paper we show that if H is a graph with p vertices, q edges, and
alpha(H)=2, then I(G*H;x) is f-symmetric for some elegant function f. In
particular, if H = K_{r}-e, we show that I(G*H;x) is symmetric and unimodal,
with a unique mode. This finding generalizes results due to (Stevanovic, 1998)
and (Mandrescu, 2012) claiming that I(G*(K_2-e);x)=I(G*2K_1;x) is symmetric and
unimodal for every graph G.


title: Below-Cutoff Propagation in Metamaterial-Lined Circular Waveguides

abstract:
  This paper investigates the propagation characteristics of circular
waveguides whose interior surface is coated with a thin metamaterial liner
possessing dispersive, negative, and near-zero permittivity. A field analysis
of this system produces the dispersion of complex modes, and reveals in detail
intriguing phenomena such as backward-wave propagation below the unlined
waveguide's fundamental-mode cutoff, resonant tunneling of power, field
collimation, and miniaturization. It is shown how the waveguide geometry and
metamaterial parameters may be selected to engineer the lined waveguide's
spectral response. Theoretical dispersion and transmission results are closely
validated by full-wave simulations.


title: ODE/IM correspondence for the Fateev model

abstract:
  The Fateev model is somewhat special among two-dimensional quantum field
theories. For different values of the parameters,it can be reduced to a variety
of integrable systems. An incomplete list of the reductions includes O(3) and
O(4) non-linear sigma models and their continuous deformations (2D and 3D
sausages, anisotropic principal chiral field), the Bukhvostov-Lipatov model,
the N=2 supersymmetric sine-Gordon model, as well as the integrable perturbed
SU_2(n)\otimes SU_2(p-2)/SU_2(n+p-2) coset CFT. The model possesses a
mysterious symmetry structure of the exceptional quantum superalgebras
U_q{\hat{\big(D(2|1;\alpha)}}\big). In this work, we propose the ODE/IM
correspondence between the Fateev model and a certain generalization of the
classical problem of constant mean curvature embedding of a thrice-punctured
sphere in AdS_3.


title: On the Laplacian of 1/r

abstract:
  A novel definition of the Laplacian of 1/r is presented, suitable for
advanced undergraduates.


title: Photometric variability in FU Ori and Z CMa as observed by MOST

abstract:
  Photometric observations obtained by the MOST satellite were used to
characterize optical small scale variability of the young stars FU Ori and Z
CMa. Wavelet analysis for FU Ori reveals the possible existence of several 2-9
d quasi-periodic features occurring nearly simultaneously; they may be
interpreted as plasma parcels or other localized disc heterogeneities revolving
at different Keplerian radii in the accretion disc. Their periods may shorten
slowly which may be due to spiralling in of individual parcels toward the inner
disc radius, estimated at 4.8+/-0.2 R_sun. Analysis of additional multicolour
data confirms the previously obtained relation between variations in the B-V
colour index and the V magnitude. In contrast to the FU Ori results, the
oscillation spectrum of Z CMa does not reveal any periodicities with the
wavelet spectrum possibly dominated by outburst of the Herbig Be component.


title:
Radiation from accelerated particles in relativistic jets with shocks,
  shear-flow, and reconnection

abstract:
  We have investigated particle acceleration and shock structure associated
with an unmagnetized relativistic jet propagating into an unmagnetized plasma.
Strong magnetic fields generated in the trailing jet shock lead to transverse
deflection and acceleration of the electrons. We have self-consistently
calculated the radiation from the electrons accelerated in the turbulent
magnetic fields. We find that the synthetic spectra depend on the bulk Lorentz
factor of the jet, the jet temperature, and the strength of the magnetic fields
generated in the shock. We have also begun study of electron acceleration in
the strong magnetic fields generated by kinetic shear (Kelvin-Helmholtz)
instabilities. Our calculated spectra should lead to a better understanding of
the complex time evolution and/or spectral structure from gamma-ray bursts,
relativistic jets, and supernova remnants.


title: Symplectic spectral geometry of semiclassical operators

abstract:
  In the past decade there has been a flurry of activity at the intersection of
spectral theory and symplectic geometry. In this paper we review recent results
on semiclassical spectral theory for commuting Berezin-Toeplitz and
h-pseudodifferential operators. The paper emphasizes the interplay between
spectral theory of operators (quantum theory) and symplectic geometry of
Hamiltonians (classical theory), with an eye towards recent developments on the
geometry of finite dimensional integrable systems.


title: Measurement of geo-neutrinos from 1353 days of Borexino

abstract:
  We present a measurement of the geo--neutrino signal obtained from 1353 days
of data with the Borexino detector at Laboratori Nazionali del Gran Sasso in
Italy. With a fiducial exposure of (3.69 $\pm$ 0.16) $\times$ $10^{31}$ proton
$\times$ year after all selection cuts and background subtraction, we detected
(14.3 $\pm$ 4.4) geo-neutrino events assuming a fixed chondritic mass Th/U
ratio of 3.9. This corresponds to a geo-neutrino signal $S_{geo}$ = (38.8 $\pm$
12.0) TNU with just a 6 $\times$ $10^{-6}$ probability for a null geo-neutrino
measurement. With U and Th left as free parameters in the fit, the relative
signals are $S_{\mathrm{Th}}$ = (10.6 $\pm$ 12.7) TNU and $S_\mathrm{U}$ =
(26.5 $\pm$ 19.5) TNU. Borexino data alone are compatible with a mantle
geo--neutrino signal of (15.4 $\pm$ 12.3) TNU, while a combined analysis with
the KamLAND data allows to extract a mantle signal of (14.1 $\pm$ 8.1) TNU. Our
measurement of a reactor anti--neutrino signal $S_{react}$ =
84.5$^{+19.3}_{-18.9}$ TNU is in agreement with expectations in the presence of
neutrino oscillations.


title:
From A1 to D5: Towards a Forcing-Related Classification of Relational
  Structures

abstract:
  We investigate the partial orderings of the form (P(X),\subset), where X is a
relational structure and P(X) the set of the domains of its isomorphic
substructures. A rough classification of countable binary structures
corresponding to the forcing-related properties of the posets of their copies
is obtained.


title:
New approach for modeling of transiting exoplanets for arbitrary
  limb-darkening law

abstract:
  We present a new solution of the direct problem of planet transits based on
transformation of double integrals to single ones. On the basis of our direct
problem solution we created the code TAC-maker for rapid and interactive
calculation of synthetic planet transits by numerical computations of the
integrals. The validation of our approach was made by comparison with the
results of the wide-spread Mandel & Agol (2002) method for the cases of linear,
quadratic and squared root limb-darkening laws and various combinations of
model parameters. For the first time our approach allows the use of arbitrary
limb-darkening law of the host star. This advantage together with the
practically arbitrary precision of the calculations make the code a valuable
tool that faces the challenges of the continuously increasing photometric
precision of the ground-based and space observations.


title:
Tracking the momentum flux of a CME and quantifying its influence on
  geomagnetically induced currents at Earth

abstract:
  We investigate a CME propagating towards Earth on 29 March 2011. This event
is specifically chosen for its predominately northward directed magnetic field,
so that the influence from the momentum flux onto Earth can be isolated. We
focus our study on understanding how a small Earth-directed segment propagates.
Mass images are created from the white-light cameras onboard STEREO which are
also converted into mass height-time maps (mass J-maps). The mass tracks on
these J-maps correspond to the sheath region between the CME and its associated
shock front as detected by in situ measurements at L1. A time-series of mass
measurements from the STEREO COR-2A instrument are made along the Earth
propagation direction. Qualitatively, this mass time-series shows a remarkable
resemblance to the L1 in situ density series. The in situ measurements are used
as inputs into a 3D magnetospheric space weather simulation from CCMC. These
simulations display a sudden compression of the magnetosphere from the large
momentum flux at the leading edge of the CME and predictions are made for the
time-derivative of the magnetic field (dB/dt) on the ground. The predicted
dB/dt were then compared with observations from specific equatorially-located
ground stations and show notable similarity. This study of the momentum of a
CME from the Sun down to its influence on magnetic ground stations on Earth is
presented as preliminary proof of concept, such that future attempts may try to
use remote sensing to create density and velocity time-series as inputs to
magnetospheric simulations.


title: Building a Holographic Superconductor with Higher-derivative Couplings

abstract:
  We discuss the gravitational dual of a holographic superconductor consisting
of a U(1) gauge field, a complex scalar field coupled to a charged AdS black
hole and a higher-derivative coupling between the U(1) gauge field and the
scalar with coupling constant \eta. In the presence of a magnetic field, the
system possesses localized spatially dependent droplet solutions which, in the
low temperature limit, have smaller critical temperature for \eta>0 than the
droplet solutions without the interaction term (\eta=0). In the weak magnetic
field limit, the opposite behavior is observed: the critical temperature
increases as we increase \eta. We also calculate the energy gap in the probe
limit and find that it is larger for \eta<0 than the energy gap in the
conventional case (\eta=0).


title: The Surprising Crab Nebula

abstract:
  We will present our study of the flux and spectral variability of the Crab
above 100 MeV on different timescales ranging from days to weeks. In addition
to the four main intense and day-long flares detected by AGILE and Fermi-LAT
between Sept. 2007 and Sept. 2012, we find evidence for week-long and less
intense episodes of enhanced gamma-ray emission that we call "waves".
Statistically significant "waves" show timescales of 1-2 weeks, and can occur
by themselves or in association with shorter flares. The Sept. - Oct. 2007
gamma-ray enhancement episode detected by AGILE shows both "wave" and flaring
behavior. We extend our analysis to the publicly available Fermi-LAT dataset
and show that several additional "wave" episodes can be identified. We discuss
the spectral properties of the September 2007 "wave"/flare event and show that
the physical properties of the "waves" are intermediate between steady and
flaring states. Plasma instabilities inducing "waves" appear to involve spatial
distances $ l \sim 10^{16} \,$cm and enhanced magnetic fields $B \sim (0.5 -
1)\,$}mG. Day-long flares are characterized by smaller distances and larger
local magnetic fields. Typically, the deduced total energy associated with the
"wave" phenomenon ($E_w \sim 10^{42} \, \rm erg$, where $E_w$ is the kinetic
energy of the emitting particles) is comparable with that associated to the
flares, and can reach a few percent of the total available pulsar spindown
energy. Most likely, flares and waves are the product of the same class of
plasma instabilities that we show acting on different timescales and radiation
intensities.


title: Gravitational Self-Energy and Black Holes in Newtonian Physics

abstract:
  A definition of a Newtonian black hole is possible which incorporates the
mass-energy equivalence from special relativity. However, exploiting a double
spherical shell model, it will be shown that the ensuing gravitational
self-energy and mass renormalization prevent the formation of such an object.


title: Integrability in non-perturbative QFT

abstract:
  Exact non-perturbative partition functions of coupling constants and external
fields exhibit huge hidden symmetry, reflecting the possibility to change
integration variables in the functional integral. In many cases this implies
also some non-linear relations between correlation functions, typical for the
tau-functions of integrable systems. To a variety of old examples, from matrix
models to Seiberg-Witten theory and AdS/CFT correspondence, now adds the
Chern-Simons theory of knot invariants. Some knot polynomials are already shown
to combine into tau-functions, the search for entire set of relations is still
in progress. It is already known, that generic knot polynomials fit into the
set of Hurwitz partition functions -- and this provides one more stimulus for
studying this increasingly important class of deformations of the ordinary
KP/Toda tau-functions.


title:
One-shot source coding with coded side information available at the
  decoder

abstract:
  One-shot achievable rate region for source coding when coded side information
is available at the decoder (source coding with a helper) is proposed. The
achievable region proposed is in terms of conditional smooth max Renyi entropy
and smooth max Renyi divergence. Asymptotically (in the limit of large block
lengths) this region is quantified in terms of spectral-sup conditional entropy
rate and spectral- sup mutual information rate. In particular, it coincides
with the rate region derived in the limit of unlimited independent and
identically distributed copies of the sources.


title:
Proof of the hypothesis Edmonds's, not polynomial of NPC-problems and
  classification of the problems with polynomial certificates

abstract:
  We show that the affirmation $P\subseteq NP$ (in computer science)
erroneously and we prove the justice of the hypotesis J.Edmonds's $P\neq NP$.
We show further that all the $NP$-complete problems is not polynomial and we
give the classification of the problems with the polynomial certificates.


title: Symplectic Rational Blow-up

abstract:
  Fintushel and Stern defined the rational blow-down construction [FS] for
smooth 4-manifolds, where a linear plumbing configuration of spheres $C_n$ is
replaced with a rational homology ball $B_n$, $n \geq 2$. Subsequently,
Symington [Sy] defined this procedure in the symplectic category, where a
symplectic $C_n$ (given by symplectic spheres) is replaced by a symplectic copy
of $B_n$ to yield a new symplectic manifold. As a result, a symplectic rational
blow-down can be performed on a manifold whenever such a configuration of
symplectic spheres can be found. In this paper, we define the inverse
procedure, the rational blow-up in the symplectic category, where we present
the symplectic structure of $B_n$ as an entirely standard symplectic
neighborhood of a certain Lagrangian 2-cell complex. Consequently, a symplectic
rational blow-up can be performed on a manifold whenever such a Lagrangian
2-cell complex is found.


title: Gelling by Heating

abstract:
  We introduce a simple model, a binary mixture of patchy particles, which has
been designed to form a gel upon heating. Due to the specific nature of the
particle interactions, notably the number and geometry of the patches as well
as their interaction energies, the system is a fluid both at high and at low
temperatures, whereas at intermediate temperatures the system forms a
solid-like disordered open network structure, i.e. a gel. Using molecular
dynamics we investigate the static and dynamic properties of this system.


title: Fugacity and Reheating of Primordial Neutrinos

abstract:
  We clarify in a quantitative way the impact that distinct chemical $T_c$ and
kinetic $T_k$ freeze-out temperatures have on the reduction of the neutrino
fugacity $\Upsilon_\nu$ below equilibrium, i.e. $\Upsilon_\nu<1$, and the
increase of the neutrino temperature $T_\nu$ via partial reheating. We
establish the connection between $\Upsilon_\nu$ and $T_k$ via the modified
reheating relation $T_\nu(\Upsilon_\nu)/T_\gamma$, where $T_\gamma$ is the
temperature of the background radiation. Our results demonstrate that one must
introduce the chemical nonequilibrium parameter, i.e., the fugacity,
$\Upsilon_\nu$, as an additional standard cosmological model parameter in the
evaluation of CMB fluctuations as its value allows measurement of $T_k$.


title:
Average power density spectrum of long GRBs detected with BeppoSAX/GRBM
  and with Fermi/GBM

abstract:
  From past experiments the average power density spectrum (PDS) of GRBs with
unknown redshift was found to be modelled from 0.01 to 1 Hz with a power-law,
f^(-alpha), with alpha broadly consistent with 5/3. Recent analyses of the
Swift/BAT catalogue showed analogous results in the 15-150 keV band. We carried
out the same analysis on the bright GRBs detected by BeppoSAX/GRBM and
Fermi/GBM. The BeppoSAX/GRBM data, in the energy range 40-700 keV and with 7.8
and 0.5-ms time resolutions, allowed us to explore for the first time the
average PDS at very high frequencies (up to 1 kHz) and reveal a break around
1-2 Hz, previously found in CGRO/BATSE data. The Fermi/GBM data, in the energy
band 8-1000 keV, allowed us to explore for the first time the average PDS
within a broad energy range. Our results confirm and extend the energy
dependence of the PDS slope, according to which harder photons have shallower
PDS.


title: Magnetic glassy phase in FeSeTe single crystals

abstract:
  The evolution of the magnetic order in FeSeTe crystals as a function of Se
content was investigated by means of ac/dc magnetometry and muon-spin
spectroscopy. Experimental results and self-consistent DFT calculations both
indicate that muons are implanted in vacant iron-excess sites, where they probe
a local field mainly of dipolar origin, resulting from an antiferromagnetic
(AFM) bicollinear arrangement of iron spins. This long-range AFM phase
disorders progressively with increasing Se content. At the same time all the
tested samples manifest a marked glassy character that vanishes for high Se
contents. The presence of local electronic/compositional inhomogeneities most
likely favours the growth of clusters whose magnetic moment "freezes" at low
temperature. This glassy magnetic phase justifies both the coherent muon
precession seen at short times in the asymmetry data, as well as the glassy
behaviour evidenced by both dc and ac magnetometry.


title:
Intrinsic pinning and the critical current scaling of clean epitaxial
  Fe(Se,Te) thin films

abstract:
  We report on the transport properties of clean, epitaxial Fe(Se,Te) thin
films prepared on Fe-buffered MgO (001) single crystalline substrates by pulsed
laser deposition. Near Tc a steep slope of the upper critical field for H||ab
was observed (74.1 T/K), leading to a very short out-of-plane coherence length,
\xi c, of 0.2 nm, yielding 2\xi c(0) approximately 0.4 nm. This value is
shorter than the interlayer distance (0.605 nm) between Fe-Se(Te) planes,
indicative of modulation of the superconducting order parameter along the
c-axis. An inverse correlation between the power law exponent N of the electric
field-current density (E-J) curve and the critical current density, Jc, has
been observed at 4 K, when the orientation of H was close to the ab-plane.
These results prove the presence of intrinsic pinning in Fe(Se,Te). A
successful scaling of the angular dependent Jc and the corresponding exponent N
can be realized by the anisotropic Ginzburg Landau approach with appropriate
\Gamma values 2~3.5. The temperature dependence of \Gamma behaves almost
identically to that of the penetration depth anisotropy.


title:
Multicell Random Beamforming with CDF-based Scheduling: Exact Rate and
  Scaling Laws

abstract:
  In a multicell multiuser MIMO downlink employing random beamforming as the
transmission scheme, the heterogeneous large scale channel effects of intercell
and intracell interference complicate analysis of distributed scheduling based
systems. In this paper, we extend the analysis in [1] and [2] to study the
aforementioned challenging scenario. The cumulative distribution function
(CDF)-based scheduling policy utilized in [1] and [2] is leveraged to maintain
fairness among users and simultaneously obtain multiuser diversity gain. The
closed form expression of the individual sum rate for each user is derived
under the CDF-based scheduling policy. More importantly, with this distributed
scheduling policy, we conduct asymptotic (in users) analysis to determine the
limiting distribution of the signal-to-interference-plus-noise ratio, and
establish the individual scaling laws for each user.


title:
Improved Search for $\bar \nu_\mu \rightarrow \bar \nu_e$ Oscillations
  in the MiniBooNE Experiment

abstract:
  The MiniBooNE experiment at Fermilab reports results from an analysis of
$\bar \nu_e$ appearance data from $11.27 \times 10^{20}$ protons on target in
antineutrino mode, an increase of approximately a factor of two over the
previously reported results. An event excess of $78.4 \pm 28.5$ events ($2.8
\sigma$) is observed in the energy range $200<E_\nu^{QE}<1250$ MeV. If
interpreted in a two-neutrino oscillation model,
$\bar{\nu}_{\mu}\rightarrow\bar{\nu}_e$, the best oscillation fit to the excess
has a probability of 66% while the background-only fit has a
$\chi^2$-probability of 0.5% relative to the best fit. The data are consistent
with antineutrino oscillations in the $0.01 < \Delta m^2 < 1.0$ eV$^2$ range
and have some overlap with the evidence for antineutrino oscillations from the
Liquid Scintillator Neutrino Detector (LSND). All of the major backgrounds are
constrained by in-situ event measurements so non-oscillation explanations would
need to invoke new anomalous background processes. The neutrino mode running
also shows an excess at low energy of $162.0 \pm 47.8$ events ($3.4 \sigma$)
but the energy distribution of the excess is marginally compatible with a
simple two neutrino oscillation formalism. Expanded models with several sterile
neutrinos can reduce the incompatibility by allowing for CP violating effects
between neutrino and antineutrino oscillations.


title:
Nanobatteries in redox-based resistive switches require extension of
  memristor theory

abstract:
  Redox-based nanoionic resistive memory cells (ReRAMs) are one of the most
promising emerging nano-devices for future information technology with
applications for memory, logic and neuromorphic computing. Recently, the
serendipitous discovery of the link between ReRAMs and memristors and
memristive devices has further intensified the research in this field. Here we
show on both a theoretical and an experimental level that nanoionic-type
memristive elements are inherently controlled by non-equilibrium states
resulting in a nanobattery. As a result the memristor theory must be extended
to fit the observed non zerocrossing I-V characteristics. The initial
electromotive force of the nanobattery depends on the chemistry and the
transport properties of the materials system but can also be introduced during
ReRAM cell operations. The emf has a strong impact on the dynamic behaviour of
nanoscale memories, and thus, its control is one of the key factors for future
device development and accurate modelling.


title: Born-Jordan Quantization and the Uncertainty Principle

abstract:
  The Weyl correspondence and the related Wigner formalism lie at the core of
traditional quantum mechanics. We discuss here an alternative quantization
scheme, whose idea goes back to Born and Jordan, and which has recently been
revived in another context, namely time-frequency analysis. We show that in
particular the uncertainty principle does not enjoy full symplectic covariance
properties in the Born and Jordan scheme, as opposed to what happens in the
Weyl quantization.


title: Maximally Embeddable Components

abstract:
  We investigate the partial orderings of the form (P(X),\subset), where X is a
countable binary relational structure and P(X) the set of the domains of its
isomorphic substructures and show that if the components of X are maximally
embeddable and satisfy an additional condition related to connectivity, then
the poset (P(X),\subset) is forcing equivalent to a finite power of
(P(\omega)/Fin)^+, or to (P(\omega \times \omega)/(Fin \times Fin))^+, or to
the direct product (P(\Delta)/ED_fin)^+ \times ((P(\omega)/Fin)^+)^n, for some
n \in \omega. In particular we obtain forcing equivalents of the posets of
copies of countable equivalence relations, disconnected ultrahomogeneous graphs
and some partial orderings.


title:
Crossover between integer and fractional vortex lattices in coherently
  coupled two-component Bose-Einstein condensates

abstract:
  We study effects of the internal coherent (Rabi) coupling in vortex lattices
in two-component BECs under rotation. We find how the vortex lattices without
the Rabi coupling known before are connected to the Abrikosov lattice of
integer vortices with increasing the Rabi coupling. We find that 1) for small
Rabi couplings, fractional vortices in triangular or square lattice for small
or large inter-component coupling constitute hexamers or tetramers, namely
multi-dimer bound states made of six or four vortices, respectively, 2) these
bound states are broken into a set of dimers at intermediate Rabi couplings,
and 3) vortices change their partners in various ways depending on the
inter-component coupling to organize themselves for constituting the Abrikosov
lattice of integer vortices at strong Rabi couplings.


title:
Independent Component Analysis for Filtering Airwaves in Seabed Logging
  Application

abstract:
  Marine controlled source electromagnetic (CSEM) sensing method used for the
detection of hydrocarbons based reservoirs in seabed logging application does
not perform well due to the presence of the airwaves (or sea-surface). These
airwaves interfere with the signal that comes from the subsurface seafloor and
also tend to dominate in the receiver response at larger offsets. The task is
to identify these air waves and the way they interact, and to filter them out.
In this paper, a popular method for counteracting with the above stated problem
scenario is Independent Component Analysis (ICA). Independent component
analysis (ICA) is a statistical method for transforming an observed
multidimensional or multivariate dataset into its constituent components
(sources) that are statistically as independent from each other as possible.
ICA-type de-convolution algorithm that is FASTICA is considered for mixed
signals de-convolution and considered convenient depending upon the nature of
the source and noise model. The results from the FASTICA algorithm are shown
and evaluated. In this paper, we present the FASTICA algorithm for the seabed
logging application.


title:
Nonconvex Lipschitz function in plane which is locally convex outside a
  discontinuum

abstract:
  We construct a Lipschitz function on $\er^{2}$ which is locally convex on the
complement of some totally disconnected compact set but not convex. Existence
of such function disproves a theorem that appeared in a paper by L. Pasqualini
and was also cited by other authors.


title: Integrating Space, Time, Version and Scale Using Alexandrov Topologies

abstract:
  This article introduces a novel approach to spatial database design. Instead
of extending the canonical Solid-Face-Edge-Vertex schema by, say, "hypersolids"
these classes are generalised to a common type SpatialEntity, and the
individual BoundedBy relations between two consecutive classes are generalised
to one BoundedBy relation on SpatialEntity instances. Then the pair
(SpatialEntity, BoundedBy) is a so-called incidence graph.
  The novelty about this approach uses the observation that an incidence graph
represents a topological space of SpatialEntity instances because the
BoundedBy-relation defines a so-called Alexandrov topology for them turning
them into a topological space. So spatial data becomes part of mathematical
topology and topology can be immediately applied to spatial data. For example,
continuous functions between two instances of spatial data allow the consistent
modelling of generalisation. Further, it is also possible to establish a formal
topological definition of spatial data dimension, and every topological data
model of arbitrary dimension gets a simple uniform data model. This model
covers space-time, and the version history of a spatial model can be
represented by an Alexandrov topology, too. By integrating space, time,
version, and scale into one single schema, topological queries across those
aspects are enabled through topological constructions. In fact, the topological
constructions cover a relationally complete query language for spaces and can
be redefined to operate accordingly on their graph representations.
  With these observations a relational database schema for a spatial data model
of dimension 6 and more is developed. The schema seamlessly integrates 4D
space-time, levels of detail and version history, and it can be easily expanded
to also contain non-spatial information or be linked to other data sources.


title:
Multifractal analysis for quotients of Birkhoff sums for countable
  Markov maps

abstract:
  This paper is devoted to study multifractal analysis of quotients of Birkhoff
averages for countable Markov maps. We prove a variational principle for the
Hausdorff dimension of the level sets. Under certain assumptions we are able to
show that the spectrum varies analytically in parts of its domain. We apply our
results to show that the Birkhoff spectrum for the Manneville-Pomeau map can be
discontinuous, showing the remarkable differences with the uniformly hyperbolic
setting. We also obtain results describing the Birkhoff spectrum of suspension
flows. Examples involving continued fractions are also given.


title: Incidence of low-density meteoroids of the Polonnaruwa type

abstract:
  The ingress of micrometeorites of cometary origin with densities below ~ 1 g
cm-3 into the Earth could average at least 5 tonne per day. Although much of
this is burnt upon entry through the atmosphere as meteors, a non-trivial
fraction (~10%) which have sizes of ~ 1 m could end up in the form of
Polonnaruwa-type meteorites that have mostly gone unnoticed.


title: Posets of Copies of Countable Scattered Linear Orders

abstract:
  We show that the separative quotient of the poset (P(L),\subset) of
isomorphic suborders of a countable scattered linear order L is \sigma-closed
and atomless. So, under the CH, all these posets are forcing-equivalent (to
P(\omega)/Fin).


title:
Step by step categorification of the Jones polynomial in Kauffman's
  version

abstract:
  Given any diagram of a link, we define on the cube of Kauffman's states a
"2-complex" whose homology is an invariant of the associated framed links, and
such that the graded Euler characteristic reproduces the unnormalized Kauffman
bracket. This includes a categorification of brackets skein relation. Then we
incorporate the orientation information and get a further complex on the same
cube that gives rise to a new invariant homology for oriented links, so that
the graded Euler characteristic reproduces the unnormalized Jones polynomial in
Kauffman's version. Finally we clarify the relations between this homology and
the original Khovanov homology of oriented links, extending the well known
relation between the associated two versions of the Jones polynomial.


title:
Detecting Majorana fermions in quasi-one-dimensional topological phases
  using nonlocal order parameters

abstract:
  Topological phases which host Majorana fermions can not be identified via
local order parameters. We give simple nonlocal order parameters to distinguish
quasi-one-dimensional (1D) topological superconductors of spinless fermions,
for any interacting model in the absence of time reversal symmetry. These
string or "brane" order parameters are natural for measurements in cold atom
systems using quantum gas microscopy. We propose them as a way to identify
symmetry-protected topological phases of Majorana fermions in cold atom
experiments via bulk rather than edge degrees of freedom. Subsequently, we
study two-dimensional (2D) topological superconductors via the quasi-1D limit
of coupling $N$ identical chains on the cylinder. We classify the symmetric,
interacting topological phases protected by the additional $\mathbb{Z}_N$
translation symmetry. The phases include quasi-1D analogs of (i) the $p+ip$
chiral topological superconductor, which can be distinguished up to the 2D
Chern number mod 2, and (ii) the 2D weak topological superconductor. We devise
general rules for constructing nonlocal order parameters which distinguish the
phases. These rules encode the signature of the fermionic topological phase in
the symmetry properties of the terminating operators of the nonlocal string or
brane. The nonlocal order parameters for some of these phases simply involve a
product of the string order parameters for the individual chains. Finally, we
give a physical picture of one of the topological phases as a condensate of
certain defects, which motivates the form of the nonlocal order parameter and
is reminiscent of higher dimensional constructions of topological phases.


title: Evidence for Two Distinct Populations of Type Ia Supernovae

abstract:
  Type Ia supernovae (SNe Ia) have been used as excellent standardizable
candles for measuring cosmic expansion, but their progenitors are still
elusive. Here we report that the spectral diversity of SNe Ia is tied to their
birthplace environments. We find that those with high-velocity ejecta are
substantially more concentrated in the inner and brighter regions of their host
galaxies than are normal-velocity SNe Ia. Furthermore, the former tend to
inhabit larger and more-luminous hosts. These results suggest that
high-velocity SNe Ia likely originate from relatively younger and more
metal-rich progenitors than normal-velocity SNe Ia, and are restricted to
galaxies with substantial chemical evolution.


title: On generalized max-linear models and their statistical interpolation

abstract:
  We propose a way how to generate a max-stable process in $C[0,1]$ from a
max-stable random vector in $\mathbb R^d$ by generalizing the \emph{max-linear
model} established by \citet{wansto11}. It turns out that if the random vector
follows some finite dimensional distribution of some initial max-stable
process, the approximating processes converge uniformly to the original process
and the pointwise mean squared error can be represented in a closed form. The
obtained results carry over to the case of generalized Pareto processes. The
introduced method enables the reconstruction of the initial process only from a
finite set of observation points and, thus, reasonable prediction of max-stable
processes in space becomes possible. A possible extension to arbitrary
dimension is outlined.


title: Individual Alpha Elements, C, N, and Ba in Early Type Galaxies

abstract:
  Spectral data on early type galaxies is analyzed for chemical abundance with
an emphasis on obtaining detailed abundances for the elements O and Si in
addition to C, N, Na, Mg, Ca, Fe, and Ba. The abundance trends with velocity
dispersion fit preconceptions based upon previous Mg conclusions, namely that
larger galaxies have a higher alpha element to iron peak ratio indicative of a
higher ratio of Type II to Type Ia supernova products. The heaviest alpha
elements, Ca and Ti, do not participate in this trend, although this fact does
not necessarily alter the basic picture given the uncertainties in
nucleosynthetic yields. Elements that likely have significant contributions
from intermediate-mass stars, namely C, N, and Ba, also gain ground relative to
Fe in massive galaxies at a modest level, with the Ba conclusion uncertain from
our data alone.


title:
Coupled-channel analysis of $K\Sigma$ production on the nucleon up to
  2.0 GeV

abstract:
  A coupled-channel effective Lagrangian model respecting unitary and gauge
invariance is applied to the combined analysis of the $(\pi,\gamma) N \to
K\Sigma$ reactions for the center of mass energies up to 2 GeV. The recent
photoproduction data obtained by the CLAS, CBELSA, LEPS, and GRAAL groups are
included into our calculations with the aim to extract the resonance couplings
to the $K\Sigma$ state. Both resonances and background contributions are found
to be important to reproduce a correct shape of the angular distributions and
polarization observables. Our description to the data is of good quality. The
extracted properties of isospin $I = 3/2$ resonances are discussed in detail
while the $I = 1/2$ resonances are largely determined by the non-strangeness
channels.