title: A Pathway Idea in Model Building

abstract:
  The pathway idea is a way of going from one family of functions to another
family of functions and yet another family of functions through a parameter in
the model so that a switching mechanism is introduced into the model through a
parameter. The advantage of the idea is that the model can cover the ideal or
stable situation in a physical situation as well as cover the unstable
neighborhoods or move from unstable neighborhoods to the stable situation. The
basic idea is illustrated for the real scalar case here and its connections to
topics in astrophysics and non-extensive statistical mechanics, namely
superstatistics and Tsallis statistics, Mittag-Leffler models, hypergeometric
functions and generalized special functions such as the H-function etc are
pointed out. The pathway idea is available for the real and complex rectangular
matrix variate cases but only the real scalar case is illustrated here.


title:
Constraints on the topology of the Universe derived from the 7-year WMAP
  CMB data and prospects of constraining the topology using CMB polarisation
  maps

abstract:
  We impose constraints on the topology of the Universe determined from a
search for matched circles in the cosmic microwave background (CMB) temperature
anisotropy patterns of the 7-year WMAP data. We pay special attention to the
sensitivity of the method to residual foreground contamination of the sky maps.
A search for pairs of matched back-to-back circles in the higher resolution
WMAP W-band map allows tighter constraints to be imposed on topology. Our
results rule out universes with topologies that predict pairs of such circles
with radii larger than approximately 10 degrees. This places a lower bound on
the size of the fundamental domain for a flat universe of about 27.9 Gpc. We
study also the possibility for constraining the topology of the Universe by
means of the matched circles statistic applied to polarised CMB anisotropy
maps. The advantages of using the CMB polarisation maps in studies of the
topology over simply analysing the temperature data as has been done to-date
are clearly demonstrated. It is found that the noise levels of both Planck and
next generation CMB experiments data are no longer prohibitive and should be
low enough to enable the use of the polarisation maps for such studies.


title:
Multivariate estimates for the concentration functions of weighted sums
  of independent identically distributed random variables

abstract:
  Let $X,X_1,\ldots,X_n$ be independent identically distributed random
variables. The paper deals with the question about the behavior of the
concentration function of the random variable $\sum\limits_{k=1}^{n}X_k a_k$
according to the arithmetic structure of vectors $a_k$. Recently, the interest
to this question has increased significantly due to the study of distributions
of eigenvalues of random matrices. In this paper we formulate and prove
multidimensional generalizations of the results Eliseeva and Zaitsev (2012).
They are also the refinements of the results of Friedland and Sodin (2007) and
Rudelson and Vershynin (2009).


title:
Wireless Information and Power Transfer: Energy Efficiency Optimization
  in OFDMA Systems

abstract:
  This paper considers orthogonal frequency division multiple access systems
with simultaneous wireless information and power transfer.
  We study the resource allocation algorithm design for maximization of the
energy efficiency of data transmission. In particular, we focus on power
splitting hybrid receivers which are able to split the received signals into
two power streams for concurrent information decoding and energy harvesting.
Two scenarios are investigated considering different power splitting abilities
of the receivers. In the first scenario, we assume receivers which can split
the received power into a continuous set of power streams with arbitrary power
splitting ratios. In the second scenario, we examine receivers which can split
the received power only into a discrete set of power streams with fixed power
splitting ratios. In both scenarios, we formulate the corresponding algorithm
design as a non-convex optimization problem which takes into account the
circuit power consumption, the minimum data rate requirements of delay
constrained services, the minimum required system data rate, and the minimum
amount of power that has to be delivered to the receivers. Subsequently, by
exploiting fractional programming and dual decomposition, suboptimal iterative
resource allocation algorithms are proposed to solve the non-convex problems.
Simulation results illustrate that the proposed iterative resource allocation
algorithms approach the optimal solution within a small number of iterations
and unveil the trade-off between energy efficiency, system capacity, and
wireless power transfer.


title: Character rigidity for special linear groups

abstract:
  In this paper we study characters on special linear groups SL_n(R), where R
is either an infinite field or the localization of an order in a number field.
We give several applications to the theory of measure preserving actions,
operator-algebraic superrigidity, and almost homomorphisms.


title:
Enhancing the W State Quantum Network Fusion Process with A Single
  Fredkin Gate

abstract:
  Integrating a single Fredkin (controlled swap) gate to the previously
introduced W state fusion mechanism (Ozdemir et al, N. J. Phys. 13, 103003,
2011) and using an ancillary photon, we increase the size of the fused W states
and essentially, we improve the success probability of the fusion process in a
promising way for a possible deterministic W state fusion mechanism. Besides
fusing arbitrary size W states, our setup can also fuse Bell states to create W
states with a success probability 3/4 which is much higher than the previous
works. Therefore using only this setup, it is now possible to start with Bell
pairs to create and expand arbitrary size W states. Since higher probability of
success implies a lower cost of resource in terms of the number of the states
spent to achieve a target size, our setup gives rise to more cost-efficient
scenarios.


title:
A convergent linear finite element scheme for the
  Maxwell-Landau-Lifshitz-Gilbert equation

abstract:
  We consider a lowest-order finite element discretization of the nonlinear
system of Maxwell's and Landau-Lifshitz-Gilbert equations (MLLG). Two
algorithms are proposed to numerically solve this problem, both of which only
require the solution of at most two linear systems per timestep. One of the
algorithms is fully decoupled in the sense that each timestep consists of the
sequential computation of the magnetization and afterwards the magnetic and
electric field. Under some mild assumptions on the effective field, we show
that both algorithms converge towards weak solutions of the MLLG system.
Numerical experiments for a micromagnetic benchmark problem demonstrate the
performance of the proposed algorithms.


title:
Integrable three-state vertex models with weights lying on genus five
  curves

abstract:
  We investigate the Yang-Baxter algebra for $\mathrm{U}(1)$ invariant
three-state vertex models whose Boltzmann weights configurations break
explicitly the parity-time reversal symmetry. We uncover two families of
regular Lax operators with nineteen non-null weights which ultimately sit on
algebraic plane curves with genus five. We argue that these curves admit degree
two morphisms onto elliptic curves and thus they are bielliptic. The associated
$\mathrm{R}$-matrices are non-additive in the spectral parameters and it has
been checked that they satisfy the Yang-Baxter equation. The respective
integrable quantum spin-1 Hamiltonians are exhibited.


title:
Heuristic Classification of Physical Theories based on Quantum
  Correlations

abstract:
  Taking quantum formalism as a point of reference and connection, we explore
the various possibilities that arise in the construction of physical theories.
Analyzing the distinct physical phenomena that each of them may describe, we
introduce the different types of hidden variables theories that correspond to
these physical phenomena. A hierarchical classification of the offered
theories, based on the degree of correlation between dichotomic observables in
bipartite systems, as quantified by a Bell type inequality, is finally
proposed.


title:
Quasi-convexity of the asymptotic channel MSE in regularized semi blind
  estimation

abstract:
  In this paper, the quasi-convexity of a sum of quadratic fractions in the
form $\sum_{i=1}^n \frac{1+c_i x^2}{\left(1+d_ix\right)^2}$ is demonstrated
where $c_i$ and $d_i$ are strictly positive scalars, when defined on the
positive real axis $\mathbb{R}^{+}$. It will be shown that this quasi-convexity
guarantees it has a unique local (and hence global) minimum.
  Indeed, this problem arises when considering the optimization of the
weighting coefficient in regularized semi-blind channel identification problem,
and more generally, is of interest in other contexts where we combine two
different estimation criteria.
  Note that V. Buchoux {\it et.al} have noticed by simulations that the
considered function has no local minima except its unique global minimum but
this is the first time this result, as well as the quasi-convexity of the
function is proved theoretically.


title:
Monte Carlo Simulation of the Photon-Tagger Focal-Plane Electronics at
  the MAX IV Laboratory

abstract:
  Rate-dependent effects in the electronics used to instrument the tagger focal
plane at the MAX IV Laboratory have been investigated using the novel approach
of Monte Carlo simulation. Results are compared to analytical calculations as
well as experimental data for both specialized testing and production running
to demonstrate a thorough understanding of the behavior of the detector system.


title: Constraints on the Tensor-to-Scalar ratio for non-power-law models

abstract:
  Recent cosmological observations hint at a deviation from the simple
power-law form of the primordial spectrum of curvature perturbations. In this
paper we show that in the presence of a tensor component, a turn-over in the
initial spectrum is preferred by current observations, and hence non-power-law
models ought to be considered. For instance, for a power-law parameterisation
with both a tensor component and running parameter, current data show a
preference for a negative running at more than $2.5\sigma$ C.L. As a
consequence of this deviation from a power-law, constraints on the
tensor-to-scalar ratio $r$ are slightly broader. We also present constraints on
the inflationary parameters for a model-independent reconstruction and the
Lasenby & Doran (LD) model. In particular, the constraints on the
tensor-to-scalar ratio from the LD model are: $r_{\rm LD}=0.11\pm{0.024}$. In
addition to current data, we show expected constraints from Planck-like and
CMB-Pol sensitivity experiments by using Markov-Chain-Monte-Carlo sampling
chains. For all the models, we have included the Bayesian Evidence to perform a
model selection analysis. The Bayes factor, using current observations, shows a
strong preference for the LD model over the standard power-law
parameterisation, and provides an insight into the accuracy of differentiating
models through future surveys.


title:
On multi-class learning through the minimization of the confusion matrix
  norm

abstract:
  In imbalanced multi-class classification problems, the misclassification rate
as an error measure may not be a relevant choice. Several methods have been
developed where the performance measure retained richer information than the
mere misclassification rate: misclassification costs, ROC-based information,
etc. Following this idea of dealing with alternate measures of performance, we
propose to address imbalanced classification problems by using a new measure to
be optimized: the norm of the confusion matrix. Indeed, recent results show
that using the norm of the confusion matrix as an error measure can be quite
interesting due to the fine-grain informations contained in the matrix,
especially in the case of imbalanced classes. Our first contribution then
consists in showing that optimizing criterion based on the confusion matrix
gives rise to a common background for cost-sensitive methods aimed at dealing
with imbalanced classes learning problems. As our second contribution, we
propose an extension of a recent multi-class boosting method --- namely
AdaBoost.MM --- to the imbalanced class problem, by greedily minimizing the
empirical norm of the confusion matrix. A theoretical analysis of the
properties of the proposed method is presented, while experimental results
illustrate the behavior of the algorithm and show the relevancy of the approach
compared to other methods.


title: Designing ferromagnetism in vanadium-oxide based superlattices

abstract:
  Motivated by recent reports (Phys. Rev. B\textbf{80}, 241102) of
room-temperature ferromagnetism in vanadium-oxide based superlattices, a
single-site dynamical mean field study of the dependence of the
paramagnetic-ferromagnetic phase boundary on superlattice geometry was
performed. An examination of variants of the experimentally determined crystal
structure indicate that ferromagnetism is found only in a small and probably
inaccessible region of the phase diagram. Design criteria for increasing the
range over which ferromagnetism might exist are proposed.


title: Separating Topology and Geometry in Space Planning

abstract:
  We are dealing with the problem of space layout planning here. We present an
architectural conceptual CAD approach. Starting with design specifications in
terms of constraints over spaces, a specific enumeration heuristics leads to a
complete set of consistent conceptual design solutions named topological
solutions. These topological solutions which do not presume any precise
definitive dimension correspond to the sketching step that an architect carries
out from the Design specifications on a preliminary design phase in
architecture.


title: Comparison of the geometric bar and W-constructions

abstract:
  We show that, for a simplicial group K,the realization of the W-construction
of K is naturally homeomorphic to the universal bundle of its geometric
realization. The argument involves certain recursive descriptions of the
W-construction and classifying bundle and relies on the facts that the
realization functor carries an action of a simplicial group to a geometric
action of its realization and preserves reduced cones and colimits


title:
A comment on the generalization of the Marinatto-Weber quantum game
  scheme

abstract:
  Iqbal and Toor [Phys. Rev. A {\bf 65}, 022306 (2002)] and [Commun. Theor.
Phys. {\bf 42}, 335 (2004)] generalized the Marinatto-Weber quantum scheme for
$2 \times 2$ games in order to study bimatrix games of $3 \times 3$ dimension,
in particular the Rock-Paper-Scissors game. In our paper we show that Iqbal and
Toor's generalization exhibits certain undesirable property that can
considerably influence the game result. To support our argumentation, in the
further part of the paper we construct the protocol corresponding to the MW
concept for any finite bimatrix game that is free from the fault.


title: Method of images applied to an opto-mechanical Fabry-Perot resonator

abstract:
  The method of images, when applied to an opto-mechanical Fabry-Perot
resonator with a heavy, charged mirror, and a light, charged mirror that can be
driven into motion, reveals that the highest order images can move
relativistically when the Q of the superconducting resonator is on the order of
10^10. The implications of such relativistic motions of the charge and mass of
these images to the emission of electromagnetic and gravitational radiation
within the resonator is explored.


title:
The singlet contribution to the Bjorken sum rule for polarized deep
  inelastic scattering

abstract:
  It is shown that the existing four-loop result for the Bjorken polarized sum
rule for deep inelastic electron-nucleon scattering obtained within
perturbative Quantum Chromodynamics should be supplemented by the calculation
of the diagrams of the so called singlet type. We also give an explanation of
the interesting coincidence of two different classes of diagrams, one of the
non-singlet and one of the singlet type, contributing the
$\alpha_s^4$-approximation to the total cross-section of electron-positron
annihilation into hadrons.


title: A quintessence scalar field with a constant-equation-of-state potential

abstract:
  In this paper we study a quintessence scalar field in a potential
exponentially decreasing with e-folding number, and show that the universe is
currently undergoing an accelerated expansion and could probably remain
accelerating indefinitely.


title: Monte-Carlo simulation of stellar intensity interferometry

abstract:
  Stellar intensity interferometers will achieve stellar imaging with a tenth
of a milli- arcsecond resolution in the optical band by taking advantage of the
large light collect- ing area and broad range of inter-telescope distances
offered by future gamma-ray Air Cherenkov Telescope (ACT) arrays. Up to now,
studies characterizing the capabilities of intensity interferometers using ACTs
have not accounted for realistic effects such as telescope mirror extension,
detailed photodetector time response, excess noise, and night sky
contamination. In this paper, we present the semi-classical quantum optics
Monte-Carlo simulation we developed in order to investigate these experimental
limi- tations. In order to validate the simulation algorithm, we compare our
first results to models for sensitivity and signal degradation resulting from
mirror extension, pulse shape, detector excess noise, and night sky
contamination.


title:
Low-energy, planar magnetic defects in BaFe2As2: nanotwins, twins,
  antiphase and domain boundaries

abstract:
  In BaFe2As2, structural and magnetic planar defects begin to proliferate
below the structural phase transition, affecting descriptions of magnetism and
superconductivity. We study using density-functional theory the stability and
magnetic properties of competing antiphase and domain boundaries, twins and
isolated $nano$twins (twin nuclei) - spin excitations proposed and/or observed.
These nanoscale defects have very low surface energy ($22$-$210$~$m$Jm$^{-2}$),
with twins favorable to the mesoscale. Defects exhibit smaller moments confined
near their boundaries -- making a uniform-moment picture inappropriate for
long-range magnetic order in real samples. {\it{Nano}}twins explain features in
measured pair distribution functions, so should be considered when analyzing
scattering data. All these defects can be weakly mobile and/or have
fluctuations that lower assessed "ordered" moments from longer spatial and/or
time averaging, and should be considered directly.


title: Planar graphs with maximum degree D at least 8 are (D+1)-edge-choosable

abstract:
  We consider the problem of list edge coloring for planar graphs. Edge
coloring is the problem of coloring the edges while ensuring that two edges
that are incident receive different colors. A graph is k-edge-choosable if for
any assignment of k colors to every edge, there is an edge coloring such that
the color of every edge belongs to its color assignment. Vizing conjectured in
1965 that every graph is (D+1)-edge-choosable, where D is the maximum degree.
In 1990, Borodin solved the conjecture for planar graphs with maximum degree at
least 9, and asked whether the bound could be lowered to 8. We prove here that
planar graphs with maximum degree D at least 8 are (D+1)-edge-choosable.


title:
Relative performance of ancilla verification and decoding in the
  [[7,1,3]] Steane code

abstract:
  Ancilla post-selection is a common means of achieving fault-tolerance in
quantum error-correction. However, it can lead to additional data errors due to
movement or wait operations. Alternatives to post-selection may achieve lower
overall failure rates due to avoiding such errors. We present numerical
simulation results comparing the logical error rates for the fault-tolerant
[[7,1,3]] Steane code using techniques of ancilla verification vs. the newer
method of ancilla decoding, as described in [D.P. DiVincenzo and P. Aliferis,
PRL 98, 020501 (2007)]. We simulate QEC procedures in which rhe possibility of
ancilla verification failures requires the creation and storage of additional
ancillas and/or additional waiting of the data until a new ancilla can be
created. We find that the decoding method, which avoids verification failures,
is advantageous in terms of overall error rate in various cases, even when
measurement operations are no slower than others. We analyze the effect of
different classes of physical error on the relative performance of these two
methods.


title:
Near- and Far-Field Response to Compact Acoustic Sources in Stratified
  Convection Zones

abstract:
  The role of the acoustic continuum associated with compact sources in the
Sun's interior wave field is explored for a simple polytropic model. The
continuum produces a near-field acoustic structure -- the so-called `acoustic
jacket' -- that cannot be represented by a superposition of discrete normal
modes. Particular attention is paid to monochromatic point sources of various
frequency and depth, and to the surface velocity power that results, both in
the discrete f- and p-mode spectrum and in the continuum. It is shown that a
major effect of the continuum is to heal the surface wave field produced by
compact sources, and therefore to hide them from view. It is found that the
continuous spectrum is not a significant contributor to observable inter-ridge
seismic power.


title: Dimer models and crepant resolutions

abstract:
  We study variations of tautological bundles on moduli spaces of
representations of quivers with relations associated with dimer models under a
change of stability parameters. We prove that if the tautological bundle
induces a derived equivalence for some stability parameter, then the same holds
for any generic stability parameter, and any projective crepant resolution can
be obtained as the moduli space for some stability parameter. This result is
used in 0905.0059 to prove the abelian McKay correspondence without using the
result of math/9908027.


title: Approximation in K-theory for Waldhausen Quasicategories

abstract:
  We prove a series of Approximation Theorems in the setting of Waldhausen
quasicategories. These theorems, inspired by Waldhausen's 1985 Approximation
Theorem, give sufficient conditions for an exact functor of Waldhausen
quasicategories to induce a level-wise weak homotopy equivalence of K-theory
spectra.
  The Pre-Approximation Theorem, which holds in the general setting of
quasicategories without Waldhausen structures, provides sufficient conditions
for a functor F:A->B to restrict to an equivalence of the maximal
infinity-groupoids in A and B.
  Our Approximation Theorems follow from the Pre-Approximation Theorem. The
Approximation Theorem in the quasicategorical setting most analogous to
Waldhausen's is: if an exact functor F:A -> B satisfies Waldhausen's App 1 and
App 2, and the domain A admits colimits of the aforementioned type and F
preserves them, then K(F) is a level-wise equivalence. As a corollary, if F is
an exact functor with ho(F) an equivalence of ordinary categories, and every
morphism in the domain A is a cofibration, then K(F) is a level-wise
equivalence.
  We then introduce a version of App 2 called Cofibration App 2 that only
requires factorization of cofibrations Fa >-> b as (equiv) o F(cofibration) and
prove an analogous Cofibration Approximation Theorem, and a corollary for
certain functors that induce an equivalence of cofibration homotopy categories.
  We also prove that S_n^infinity is Waldhausen equivalent to
\overline{\mathcal{F}_{n-1}^infinity} using the mid anodyne maps known as spine
inclusions, and clarify how hypotheses and notions in Waldhausen structures are
related in new ways in the context of quasicategories.


title:
Choosability with separation of complete graphs and minimal abundant
  packings

abstract:
  For a graph $G$ and a positive integer $c$, let $\chi_{l}(G,c)$ be the
minimum value of $k$ such that one can properly color the vertices of $G$ from
any lists $L(v)$ such that $|L(v)|=k$ for all $v\in V(G)$ and $|L(u)\cap
L(v)|\leq c$ for all $uv\in E(G)$. Kratochv\'{i}l et al. asked to determine
$\lim_{n\rightarrow \infty} \chi_{l}(K_n,c)/\sqrt{cn}$, if exists. We prove
that the limit exists and equals 1. We also find the exact value of
$\chi_{l}(K_n,c)$ for infinitely many values of $n$.


title: Two exact algorithms for the generalized assignment problem

abstract:
  Let A={a_1,a_2,...,a_s} and B={b_1,b_2,...,b_t} be two sets of objects with
s+r=n, the generalized assignment problem assigns each element a_i in A to at
least alpha_i and at most alpha '_i elements in B, and each element b_j in B to
at least beta_j and at most beta '_j elements in A for all 1 <= i <= s and 1 <=
j <= t. In this paper, we present an O(n^4) time and O(n) space algorithm for
this problem using the well known Hungarian algorithm. We also present an
O(n^3) algorithm for a special case of the generalized assignment, called the
limited-capacity assignment problem, where alpha_i,beta_j=1 for all i,j.


title: Periodic billiard orbits of self-similar Sierpinski carpets

abstract:
  We identify a collection of periodic billiard orbits in a self-similar
Sierpinski carpet billiard table. Based on a refinement of the result of
Durand-Cartagena and Tyson regarding nontrivial line segments in a self-similar
Sierpinski carpet, we construct what is called an eventually constant sequence
of compatible periodic orbits of prefractal Sierpinski carpet billiard tables.
The trivial limit of this sequence then constitutes a periodic orbit of a
self-similar Sierpinski carpet billiard table. We also determine the
corresponding translation surface for each prefractal billiard table, and show
that the genera of a sequence of translation surfaces increase without bound.
Various open questions and possible directions for future research are offered.


title: Two-dimensional magnetic interactions in LaFeAsO

abstract:
  Inelastic neutron scattering measurements demonstrate that the magnetic
interactions in antiferromagnetic LaFeAsO are two-dimensional. Spin wave
velocities within the Fe layer and the magnitude of the spin gap are similar to
the \textit{A}Fe$_2$As$_2$ based materials. However, the ratio of interlayer
and intralayer exchange is found to be less than $\sim 10^{-4}$ in LaFeAsO,
very similar to the cuprates, and $\sim$ 100 times smaller than that found in
\textit{A}Fe$_2$As$_2$ compounds. The results suggest that the effective
dimensionality of the magnetic system is highly variable in the parent
compounds of the iron arsenides and weak 3-D interactions may limit the maximum
attainable superconducting $T_{c}$.


title: Generalized Riemann curvature corrections to type II supergravity

abstract:
  We observe that the replacement of the Riemann curvature with the generalized
Riemann curvature into the corrections to the type II supergravity at order
$\alpha'^3$ which are in terms of the contractions of four Riemann curvatures
$R^4$, is not fully consistent with the S-matrix elements in the superstring
theory. In particular, they produce non-zero S-matrix elements for odd number
of B-field strengths which are not consistent with the string theory results.
Using the consistency of the couplings with the linear T-duality as a guiding
principle, we consider all T-duality invariant couplings and fix their
coefficients by requiring them to be consistent with the S-matrix elements. The
new Lagrangian density is then equivalent to the replacement of the generalized
Riemann curvature into the expression $t_8t_8R^4$.


title: On the sphericity test with large-dimensional observations

abstract:
  In this paper, we propose corrections to the likelihood ratio test and John's
test for sphericity in large-dimensions. New formulas for the limiting
parameters in the CLT for linear spectral statistics of sample covariance
matrices with general fourth moments are first established. Using these
formulas, we derive the asymptotic distribution of the two proposed test
statistics under the null. These asymptotics are valid for general population,
i.e. not necessarily Gaussian, provided a finite fourth-moment. Extensive
Monte-Carlo experiments are conducted to assess the quality of these tests with
a comparison to several existing methods from the literature. Moreover, we also
obtain their asymptotic power functions under the alternative of a spiked
population model as a specific alternative.


title: Performance Analysis of OFDM-based System for Various Channels

abstract:
  The demand for high-speed mobile wireless communications is rapidly growing.
Orthogonal Frequency Division Multiplexing (OFDM) technology promises to be a
key technique for achieving the high data capacity and spectral efficiency
requirements for wireless communication systems in the near future. This paper
investigates the performance of OFDM-based system over static and non-static or
fading channels. In order to investigate this, a simulation model has been
created and implemented using MATLAB. A comparison has also been made between
the performances of coherent and differential modulation scheme over static and
fading channels. In the fading channels, it has been found that OFDM-based
system's performance depends severely on Doppler shift which in turn depends on
the velocity of user. It has been found that performance degrades as Doppler
shift increases, as expected. This paper also performs a comparative study of
OFDM-based system's performance on different fading channels and it has been
found that it performs better over Rician channel, as expected and system
performance improves as the value of Rician factor increases, as expected. As a
last task, a coding technique, Gray Coding, has been used to improve system
performace and it is found that it improves system performance by reducing BER
about 25-32 percent.


title:
PAPR Reduction of OFDM System Through Iterative Selection of Input
  Sequences

abstract:
  Orthogonal Frequency Division Multiplexing (OFDM) based multi-carrier systems
can support high data rate wireless transmission without the requirement of any
extensive equalization and yet offer excellent immunity against fading and
inter-symbol interference. But one of the major drawbacks of these systems is
the large Peak-to-Average Power Ratio (PAPR) of the transmit signal which
renders a straightforward implementation costly and inefficient. In this paper,
a new PAPR reduction scheme is introduced where a number of sequences from the
original data sequence is generated by changing the position of each symbol and
the sequence with lowest PAPR is selected for transmission. A comparison of
performance of this proposed technique with an existing PAPR reduction scheme,
i.e., the Selective Mapping (SLM) is performed. It is shown that considerable
reduction in PAPR along with higher throughput can be achieved at the expense
of some additional computational complexity.


title: Some nonrenormalizable theories are finite

abstract:
  Some nonrenormalizable theories are less singular than all renormalizable
theories, and one can use lattice simulations to extract physical information
from them. This paper discusses four nonrenormalizable theories that have
finite euclidian and minkowskian Green's functions. Two of them have finite
euclidian action densities and describe scalar bosons of finite mass. The space
of nonsingular nonrenormalizable theories is vast.


title: Some Properties of the Coordinate Rings over Finite Fields

abstract:
  In this paper, we present the Nullstellensatz in case of the coordinate rings
of a nonempty subset of Kn where K is a finite field Fq. Some applications of
the Nullstellensatz are also discussed.


title: Criteria for Hankel operators to be sign-definite

abstract:
  We show that total multiplicities of negative and positive spectra of a
self-adjoint Hankel operator $H$ with kernel $h(t)$ and of an operator of
multiplication by some real function $s(x)$ coincide. In particular, $\pm H\geq
0$ if and only if $\pm s(x)\geq 0$. The kernel $h(t)$ and its "sign-function"
$s(x)$ are related by an explicit formula. An expression of $h(t)$ in terms of
$s(x)$ leads to an exponential representation of $h(t)$.
  Our approach directly applies to various classes of Hankel operators. In
particular, for Hankel operators of finite rank, we find an explicit formula
for the total multiplicity of their negative and positive spectra.


title:
Wide viewing angle realization for sampled hologram by collecting
  high-order diffraction beams

abstract:
  We propose that viewing angle expansion of the holographic image can be
realized by using high-order diffraction beams caused by the pixel structure
sampling the hologram data. The diffractive beam propagating to new optical
axis direction plays a role in a modulated carrier similar to a carrier signal
of the off-axis holography, which makes new viewing zone of the reconstruction
image. The reconstructed image in the Fresnel hologram is deformed along new
viewing direction, whereas the Fourier hologram enables to retrieve
three-dimensional image with other perspective. High resolution hologram fringe
is imaged on the image plane through an imaging system, and thus, only
collection of diffracted beams increases a viewing zone angle. We verify our
proposal through the numerical analysis for the sampled hologram showing
high-order diffraction beams with various viewing zones.


title: Chaos and Entropic Chaos in Kac's Model Without High Moments

abstract:
  In this paper we present a new local L\'evy Central Limit Theorem, showing
convergence to stable states that are not necessarily the Gaussian, and use it
to find new and intuitive entropically chaotic families with underlying
one-particle function that has moments of order $2\alpha$, with $1<\alpha<2$.
We also discuss a lower semi continuity result for the relative entropy with
respect to our specific family of functions, and use it to show a form of
stability property for entropic chaos in our settings.


title: Severi inequality for varieties of maximal Albanese dimension

abstract:
  Let $X$ be a projective, normal, minimal and Gorenstein $n$-dimensional
complex variety of general type. Suppose $X$ is of maximal Albanese dimension.
We prove that $K^n_X \ge 2 n! \chi(K_X)$


title: The Quantitative Characterization of Finite Simple Groups

abstract:
  In this report we summarize this work, all finite simple groups $G$ can
determined uniformly using their orders $|G|$ and the set $\pi_e(G)$ of their
element orders.


title:
Max-min-plus expressions for one-dimensional particle cellular automata
  obtained from a fundamental diagram

abstract:
  We study one-dimensional neighborhood-five conservative cellular automata
(CA), referred to as particle cellular automata five (particle CA5). We show
that evolution equations for particle CA5s that belong to certain types can be
obtained in the form of max-min-plus expressions from a fundamental diagram.
The obtained equations are transformed into other max-min-plus expressions by
ultradiscrete Cole-Hopf transformation, which enable us to analyze the
asymptotic behaviors of general solutions. The equations in the Lagrange
representation, which describe particle motion, are also presented, which too
can be obtained from a fundamental diagram. Finally, we discuss the
generalization to a one-dimensional conservative neighborhood-$n$ CA, i.e.,
particle CA$n$.


title: Classification of quantum groups and Belavin-Drinfeld cohomologies

abstract:
  In the present article we discuss the classification of quantum groups whose
quasi-classical limit is a given simple complex Lie algebra $\mathfrak{g}$.
This problem reduces to the classification of all Lie bialgebra structures on
$\mathfrak{g}(\mathbb{K})$, where $\mathbb{K}=\mathbb{C}((\hbar))$. The
associated classical double is of the form
$\mathfrak{g}(\mathbb{K})\otimes_{\mathbb{K}} A$, where $A$ is one of the
following: $\mathbb{K}[\epsilon]$, where $\epsilon^{2}=0$, $\mathbb{K}\oplus
\mathbb{K}$ or $\mathbb{K}[j]$ where $j^{2}=\hbar$. The first case relates to
quasi-Frobenius Lie algebras. In the second and third cases we introduce a
theory of Belavin-Drinfeld cohomology associated to any non-skewsymmetric
$r$-matrix from the Belavin-Drinfeld list. We prove a one-to-one correspondence
between gauge equivalence classes of Lie bialgebra structures on
$\mathfrak{g}(\mathbb{K})$ and cohomology classes (in case II) and twisted
cohomology classes (in case III) associated to any non-skewsymmetric
$r$-matrix.


title: The local description of discrete Mechanics

abstract:
  In this paper, we introduce local expressions for discrete Mechanics. To
apply our results simultaneously to several interesting cases, we derive these
local expressions in the framework of Lie groupoids, following the program
proposed by Alan Weinstein in [19]. To do this, we will need some results on
the geometry of Lie groupoids, as, for instance, the construction of symmetric
neighborhoods or the existence of local bisections. These local descriptions
will be particular useful for the explicit construction of geometric
integrators for mechanical systems (reduced or not), in particular, discrete
Euler-Lagrange equations, discrete Euler-Poincar\'e equations, discrete
Lagrange-Poincar\'e equations... The results contained in this paper can be
considered as a local version of the study that we have started in [13], on the
geometry of discrete Mechanics on Lie groupoids.


title:
The Eigenvectors of the Zero Laplacian and Signless Laplacian
  Eigenvalues of a Uniform Hypergraph

abstract:
  In this paper, we show that the eigenvectors of the zero Laplacian and
signless Lapacian eigenvalues of a $k$-uniform hypergraph are closely related
to some configured components of that hypergraph. We show that the components
of an eigenvector of the zero Laplacian or signless Lapacian eigenvalue have
the same modulus. Moreover, under a {\em canonical} regularization, the phases
of the components of these eigenvectors only can take some uniformly
distributed values in $\{\{exp}(\frac{2j\pi}{k})\;|\;j\in [k]\}$. These
eigenvectors are divided into H-eigenvectors and N-eigenvectors. Eigenvectors
with minimal support is called {\em minimal}. The minimal canonical
H-eigenvectors characterize the even (odd)-bipartite connected components of
the hypergraph and vice versa, and the minimal canonical N-eigenvectors
characterize some multi-partite connected components of the hypergraph and vice
versa.


title: Localization, disorder and boson peak in an amorphous solid

abstract:
  We demonstrate using the classical density functional theory (DFT) model that
an intermediate degree of mass localization in the amorphous state is essential
for producing the boson peak. The localization length $\ell$ is identified from
the width of the gaussian density profile in terms of which the inhomogeneous
density n(x) of the solid is expressed in DFT. At a fixed average density,
there exists a limiting value $\ell_0$ of $\ell$ signifying a minimum mass
localization in the amorphous state. For more delocalized states
($\ell>\ell_0$) occurrence of boson peak is unfeasible.


title:
Microscopic theory to quantify the competing kinetic processes in
  photoexcited surface-coupled quantum dots

abstract:
  We present a self-contained theoretical and computational framework for
dynamics following photoexcitation in quantum dots near planar interfaces. A
microscopic Hamiltonian parameterized by first principles calculations is
merged with a reduced density matrix formalism that allows for the prediction
of time-dependent charge and energy transfer processes between the quantum dot
and the electrode. While treating charge and energy transfer processes on an
equal footing, the non-perturbative effects of sudden charge transitions on the
Fermi sea of the electrode are included. We illustrate the formalism with
calculations of an InAs quantum dot coupled to the Shockley state on an Au[111]
surface, and use it to concretely discuss the wide range of kinetics possible
in these systems and their implications for photovoltaic systems and tunnel
junction devices. We discuss the utility of this framework for the analysis of
recent experiments.


title: The failure risk analysis of digital circuits

abstract:
  To analyze the failure risk of asynchronous digital circuits the
time-parameter is introduced into the Boolean algebra replacing the arithmetic
operations by logical operations. There considered an example of construction
of signals passing through the logical elements, using the described below
mathematical apparatus.


title: Low Energy Cosmic Rays and the Disturbed Magnetosphere

abstract:
  Low energy galactic cosmic rays as well as particles accelerated to high
energies either at the solar surface or in the interplanetary medium have
access to the atmosphere above a given position on the Earth depending upon the
state of the magnetosphere. The interpretation of the cosmic ray anisotropy,
deduced from the neutron monitor (NM) network, must assume the variability of
the magnetospheric configuration. Along with a short review of changes of the
geomagnetic cutoffs in the disturbed magnetosphere reported in the earlier
papers, we present the results of computations of transmissivity function and
asymptotic directions for selected points on the ground and for a low altitude
polar orbiting satellite as well. The computations, based on different
available models of geomagnetic field of external sources are performed for
quiet time periods and for strong geomagnetic disturbances occurred in 2003 and
2004.


title:
Major changes in the core developmental pathways of nematodes:
  Romanomermis culicivorax reveals the derived status of the Caenorhabditis
  elegans model

abstract:
  Background Despite its status as a model organism, the development of
Caenorhabditis elegans is not necessarily archetypical for nematodes. The
phylum Nematoda is divided into the Chromadorea (indcludes C. elegans) and the
Enoplea. Compared to C. elegans, enoplean nematodes have very different
patterns of cell division and determination. Embryogenesis of the enoplean
Romanomermis culicivorax has been studied in great detail, but the genetic
circuitry underpinning development in this species is unknown. Results We
created a draft genome of R. culicivorax and compared its developmental gene
content with that of two nematodes, C. elegans and Trichinella spiralis
(another enoplean), and a representative arthropod Tribolium castaneum. This
genome evidence shows that R. culicivorax retains components of the conserved
metazoan developmental toolkit lost in C. elegans. T. spiralis has
independently lost even more of the toolkit than has C. elegans. However, the
C. elegans toolkit is not simply depauperate, as many genes essential for
embryogenesis in C. elegans are unique to this lineage, or have only extremely
divergent homologues in R. culicivorax and T. spiralis. These data imply
fundamental differences in the genetic programmes for early cell specification,
inductive interactions, vulva formation and sex determination. Conclusions Thus
nematodes, despite their apparent phylum-wide morphological conservatism, have
evolved major differences in the molecular logic of their development. R.
culicivorax serves as a tractable, contrasting model to C. elegans for
understanding how divergent genomic and thus regulatory backgrounds can
generate a conserved phenotype. The availability of the draft genome will
promote use of R. culicivorax as a research model.


title:
Monitoring the Gamma-ray Sky through 4.5 Years of Fermi LAT Flare
  Advocate Service

abstract:
  The Fermi Flare Advocate (also known as Gamma-ray Sky Watcher, FA-GSW)
service provides for a quick look and review of the gamma-ray sky observed
daily by the Fermi Large Area Telescope (LAT). The FA-GSW service provides
alerts and communicates to the external scientific community potentially new
gamma-ray sources, interesting transients and source flares. A weekly digest
containing the highlights about the variable LAT gamma-ray sky at E>100 MeV is
published in the web ("Fermi Sky Blog"). Other news items are occasionally
posted through the Fermi multiwavelength mailing list, Astronomer's Telegrams
(ATels) and Gamma-ray Coordination Network notes (GCNs). From July 2008 to
January 2013 about 230 ATels and some GCNs have been published by the Fermi LAT
Collaboration, more than 40 target of opportunity observing programs have been
triggered by the LAT Collaboration and performed though the Swift satellite,
and individual observing alerts have been addressed to ground-based Cherenkov
telescopes. This is helping the Fermi mission to catch opportunities offered by
the variable high-energy sky, increasing the rate of simultaneous
multifrequency observations and the level of international scientific
cooperation.


title: 1-D Schr\"odinger operators with local point interactions: a review

abstract:
  We review recent developments in the theory of 1-D Schr\"odinger operators
with local point interactions on a discrete set. The progress in this area was
stimulated by recent advances in the extension theory of symmetric operators
and in the theory of ordinary differential operators with distributional
coefficients.


title:
A weaving process to define requirements for Cooperative Information
  System

abstract:
  The development of a Cooperative Information System (CIS) becomes more and
more complex, new challenges arise for managing this complexity. So, the aspect
paradigm is regarded as a promising software development technique which can
reduce the complexity and cost of developing large software systems. This
opportunity can be used to develop a CIS able to support the interconnection of
organizations information systems in order to ensure a common global service
and to support the tempo of change in the business world that is increasing at
an exponential level. We previously proposed an approach named AspeCiS (An
Aspect-oriented Approach to Develop a Cooperative Information System) to
develop a Cooperative Information System from existing Information Systems by
using their artifacts such as existing requirements, and design. In this
approach we have studied how to elicit CIS Requirements called Cooperative
Requirements in AspeCiS. In this paper we propose a weaving process to define
these requirements by reusing existing requirements and new aspectual
requirements that we define to modify these requirements in order to be reused.


title: Statistical Mechanics of Multiplex Ensembles: Entropy and Overlap

abstract:
  There is growing interest in multiplex networks where individual nodes take
part in several layers of networks simultaneously. This is the case for example
in social networks where each individual node has different kind of social ties
or transportation systems where each location is connected to another location
by different types of transport. Many of these multiplex are characterized by a
significant overlap of the links in different layers. In this paper we
introduce a statistical mechanics framework to describe multiplex ensembles. A
multiplex is a system formed by N nodes and M layers of interactions where each
node belongs to the M layers at the same time. Each layer $\alpha$ is formed by
a network $G^{\alpha}$. Here we introduce the concept of correlated multiplex
ensembles in which the existence of a link in one layer is correlated with the
existence of a link in another layer. This implies that a typical multiplex of
the ensemble can have a significant overlap of the links in the different
layers. Moreover we characterize microcanonical and canonical multiplex
ensembles satisfying respectively hard and soft constraints and we discuss how
to construct multiplex in these ensembles. Finally we provide the expression
for the entropy of these ensembles that can be useful to address different
inference problems involving multiplexes.


title:
On-demand semiconductor single-photon source with near-unity
  indistinguishability

abstract:
  Single photon sources based on semiconductor quantum dots offer distinct
advantages for quantum information, including a scalable solid-state platform,
ultrabrightness, and interconnectivity with matter qubits. A key prerequisite
for their use in optical quantum computing and solid-state networks is a high
level of efficiency and indistinguishability. Pulsed resonance fluorescence
(RF) has been anticipated as the optimum condition for the deterministic
generation of high-quality photons with vanishing effects of dephasing. Here,
we generate pulsed RF single photons on demand from a single,
microcavity-embedded quantum dot under s-shell excitation with 3-ps laser
pulses. The pi-pulse excited RF photons have less than 0.3% background
contributions and a vanishing two-photon emission probability.
Non-postselective Hong-Ou-Mandel interference between two successively emitted
photons is observed with a visibility of 0.97(2), comparable to trapped atoms
and ions. Two single photons are further used to implement a high-fidelity
quantum controlled-NOT gate.


title:
Full halo coronal mass ejections: Do we need to correct the projection
  effect in terms of velocity?

abstract:
  The projection effect is one of the biggest obstacles in learning the real
properties of coronal mass ejections (CMEs) and forecasting their
geoeffectiveness. To evaluate the projection effect, 86 full halo CMEs (FHCMEs)
listed in the CDAW CME catalog from 2007 March 1 to 2012 May 31 are
investigated. By applying the Graduated Cylindrical Shell (GCS) model, we
obtain the de-projected values of the propagation velocity, direction and
angular width of these FHCMEs, and compare them with the projected values
measured in the plane-of-sky. Although these CMEs look full halo in the view
angle of SOHO, it is found that their propagation directions and angular widths
could vary in a large range, implying projection effect is a major reason
causing a CME being halo, but not the only one. Furthermore, the comparison of
the de-projected and projected velocities reveals that most FHCMEs originating
within 45$^\circ$ of the Sun-Earth line with a projected speed slower than 900
km s$^{-1}$ suffer from large projection effect, while the FHCMEs originating
far from the vicinity of solar disk center or moving faster than 900 km
s$^{-1}$ have small projection effect. The results suggest that not all of
FHCMEs need to correct projection effect for their velocities.


title: On the Landau-Lifshitz-Gilbert equation with magnetostriction

abstract:
  To describe and simulate dynamic micromagnetic phenomena, we consider a
coupled system of the nonlinear Landau-Lifshitz-Gilbert equation and the
conservation of momentum equation. This coupling allows to include
magnetostrictive effects into the simulations. Existence of weak solutions has
recently been shown in [Carbout et al. 2011]. In our contribution, we give an
alternate proof which additionally provides an effective numerical integrator.
The latter is based on lowest-order finite elements in space and a
linear-implicit Euler time-stepping. Despite the nonlinearity, only two linear
systems have to be solved per timestep, and the integrator fully decouples both
equations. Finally, we prove unconditional convergence---at least of a
subsequence---towards, and hence existence of, a weak solution of the coupled
system, as timestep size and spatial mesh-size tend to zero. Numerical
experiments conclude the work and shed new light on the existence of blow-up in
micromagnetic simulations.


title: An Erd\H{o}s--Ko--Rado theorem for matchings in the complete graph

abstract:
  We consider the following higher-order analog of the Erd\H{o}s--Ko--Rado
theorem. For positive integers r and n with r<= n, let M^r_n be the family of
all matchings of size r in the complete graph K_{2n}. For any edge e in
E(K_{2n}), the family M^r_n(e), which consists of all sets in M^r_n containing
e, is called the star centered at e. We prove that if r<n and A is an
intersecting family of matchings in M^r_n, then |A|<=|M^r_n(e)|$, where e is an
edge in E(K_{2n}). We also prove that equality holds if and only if A is a
star. The main technique we use to prove the theorem is an analog of Katona's
elegant cycle method.


title: A direct solution to the phonon Boltzmann equation

abstract:
  The frequency dependent phonon Boltzmann equation is transformed to an
integral equation over the irreducible part of the Brillouin zone. Simultaneous
diagonalization of the collision kernel of that equation and a symmetry crystal
class operator allow to obtain a spectral representation of the lattice thermal
conductivity valid at finite frequency. The method is applied to C, Si and
Mg$_2$Si to obtain the static and dynamical thermal conductivities.


title:
Magnetism of CuX2 frustrated chains (X = F, Cl, Br): the role of
  covalency

abstract:
  Periodic and cluster density-functional theory (DFT) calculations, including
DFT+U and hybrid functionals, are applied to study magnetostructural
correlations in spin-1/2 frustrated chain compounds CuX2: CuCl2, CuBr2, and a
fictitious chain structure of CuF2. The nearest-neighbor and second-neighbor
exchange integrals, J1 and J2, are evaluated as a function of the Cu-X-Cu
bridging angle, theta, in the physically relevant range 80-110deg. In the ionic
CuF2, J1 is ferromagnetic for theta smaller 100deg. For larger angles, the
antiferromagnetic superexchange contribution becomes dominant, in accord with
the Goodenough-Kanamori-Anderson rules. However, both CuCl2 and CuBr2 feature
ferromagnetic J1 in the whole angular range studied. This surprising behavior
is ascribed to the increased covalency in the Cl and Br compounds, which
amplifies the contribution from Hund's exchange on the ligand atoms and renders
J1 ferromagnetic. At the same time, the larger spatial extent of X orbitals
enhances the antiferromagnetic J2, which is realized via the long-range
Cu-X-X-Cu paths. Both, periodic and cluster approaches supply a consistent
description of the magnetic behavior which is in good agreement with the
experimental data for CuCl2 and CuBr2. Thus, owing to their simplicity, cluster
calculations have excellent potential to study magnetic correlations in more
involved spin lattices and facilitate application of quantum-chemical methods.


title: Searches for MSSM Higgs bosons at ATLAS and CMS

abstract:
  The Minimal Supersymmetric extension of the Standard Model (MSSM) predicts
the existence of three neutral and two charged Higgs bosons. Searches for these
MSSM Higgs bosons are presented, based on proton-proton collisions recorded in
2011 and 2012 by the ATLAS and CMS experiments at the LHC. The neutral Higgs
bosons are searched through their decays into pairs of oppositely charged tau
leptons. The exclusion limits at 95% confidence level are shown as a function
of the $m_A$ and $\tan\beta$ parameters. The search for the charged Higgs
bosons is based on their production through the decays of top quarks in the
$t\bar{t}$ process, $t \to bH^+$. The Higgs bosons subsequently decay
predominantly into a tau lepton and a neutrino. Upper limits are set on the
branching fraction $B(t \to bH^+)$, combining the final states with leptonic
and hadronic tau decay modes.


title: A construction of almost Steiner systems

abstract:
  Let $n$, $k$, and $t$ be integers satisfying $n>k>t\ge2$. A Steiner system
with parameters $t$, $k$, and $n$ is a $k$-uniform hypergraph on $n$ vertices
in which every set of $t$ distinct vertices is contained in exactly one edge.
An outstanding problem in Design Theory is to determine whether a nontrivial
Steiner system exists for $t\geq6$.
  In this note we prove that for every $k>t\ge2$ and sufficiently large $n$,
there exists an almost Steiner system with parameters $t$, $k$, and $n$; that
is, there exists a $k$-uniform hypergraph on $n$ vertices such that every set
of $t$ distinct vertices is covered by either one or two edges.


title:
The Structure of Shock Waves in the Case of Accretion onto Low-Mass
  Young Stars

abstract:
  A physical analysis and mathematical formulation of the structure of an
accretion shock wave in the case of young stars are given. Some results are
presented, and the dependence of the structure of the shock on various
parameters is investigated. In the general case, the relative intensities and
profiles of lines in the spectra of T Tauri stars should depend on the velocity
and density of the infalling gas, as well as on the accretion geometry. The
calculation results may serve as a base for elucidating the nature of the
activity of young stars.


title: The Casimir effect as a candidate of dark energy

abstract:
  It is known that the simply evaluated value of the zero point energy of
quantum fields is extremely deviated from the observed value of dark energy
density. In this paper, we consider whether the Casimir energy, which is the
zero point energy brought from boundary conditions, can cause the accelerating
expansion of the Universe by using proper renormalization method and
introducing the fermions of finite temperature living in $3+n+1$ space-time. We
show that the zero temperature Casimir energy and the finite temperature
corrections can explain the current accelerated expansion of the Universe.


title:
An accurate Newtonian description of particle motion around a
  Schwarzschild black hole

abstract:
  A generalized Newtonian potential is derived from the geodesic motion of test
particles in Schwarzschild spacetime. This potential reproduces several
relativistic features with higher accuracy than commonly used pseudo-Newtonian
approaches. The new potential reproduces the exact location of the marginally
stable, marginally bound, and photon circular orbits, as well as the exact
radial dependence of the binding energy and the angular momentum of these
orbits. Moreover, it reproduces the orbital and epicyclic angular frequencies
to better than 6%. In addition, the spatial projections of general trajectories
coincide with their relativistic counterparts, while the time evolution of
parabolic-like trajectories and the pericentre advance of elliptical-like
trajectories are both reproduced exactly. We apply this approach to a standard
thin accretion disc and find that the efficiency of energy extraction agrees to
within 3% with the exact relativistic value, while the energy flux per unit
area as a function of radius is reproduced everywhere to better than 7%. As a
further astrophysical application we implement the new approach within a
smoothed particle hydrodynamics code and study the tidal disruption of a
main-sequence star by a supermassive black hole. The results obtained are in
very good agreement with previous relativistic simulations of tidal disruptions
in Schwarzschild spacetime. The equations of motion derived from this potential
can be implemented easily within existing Newtonian hydrodynamics codes with
hardly any additional computational effort.


title: WZW models as mutual super Poisson-Lie T-dual sigma models

abstract:
  A WZW model on the Lie supergroup (C3+A) is constructed. It is shown that
this model contains super Poisson-Lie symmetry with the dual Lie supergroup C3
+ A1,1|.i. Furthermore, we show that the dual model is also equivalent to the
WZW model on isomorphic Lie supergroup (C3+A).i. In this manner, because of
isomorphism of the (C3+A) with a Manin supertriple, it is shown that the
N=(2,2) structure is preserved under the super Poisson-Lie T-duality
transformation.


title: The nonlinear development of the relativistic two-stream instability

abstract:
  The two-stream instability has been mooted as an explanation for a range of
astrophysical applications from GRBs and pulsar glitches to cosmology. Using
the first nonlinear numerical simulations of relativistic multi-species
hydrodynamics we show that the onset and initial growth of the instability is
very well described by linear perturbation theory. In the later stages the
linear and nonlinear description match only qualitatively, and the instability
does not saturate even in the nonlinear case by purely ideal hydrodynamic
effects.


title: Improved superconducting qubit coherence using titanium nitride

abstract:
  We demonstrate enhanced relaxation and dephasing times of transmon qubits, up
to ~ 60 \mu s by fabricating the interdigitated shunting capacitors using
titanium nitride (TiN). Compared to lift-off aluminum deposited simultaneously
with the Josephson junction, this represents as much as a six-fold improvement
and provides evidence that previous planar transmon coherence times are limited
by surface losses from two-level system (TLS) defects residing at or near
interfaces. Concurrently, we observe an anomalous temperature dependent
frequency shift of TiN resonators which is inconsistent with the predicted TLS
model.


title:
Hidden $(\pi,0)$ instability as an itinerant origin of bicollinear
  antiferromagnetism in Fe$_{1+x}$Te

abstract:
  By calculating orbitally resolved Pauli susceptibilities within maximally
localized Wannier orbital basis transformed from first principles band
structures, we find that magnetism in Fe$_{1+x}$Te still has its itinerant
origin even without Fermi surface nesting, provided orbital modulation of
particle-hole excitations are considered. This leads to strong magnetic
instabilities at wave vector (0,$\pi$)/($\pi$,0) in d$_{xz}$/d$_{yz}$ orbitals
that are responsible for the bicollinear antiferromagnetic state as extra
electrons donated from excess Fe are considered. Magnetic exchange coupling
between excess Fe and in-plane Fe further stabilizes the bicollinear
antiferromagnetic order. Our results reveal that magnetism and
superconductivity in iron chalcogenides may have different orbital origin, as
Pauli susceptibilities of different orbitals evolve differently as a function
of concentration of excess Fe and height of the chalcogen atom measured from
the iron plane.


title: Orthogonal Dual Hyperovals, Symplectic Spreads and Orthogonal Spreads

abstract:
  Orthogonal spreads in orthogonal spaces of type $V^+(2n+2,2)$ produce large
numbers of rank $n$ dual hyperovals in orthogonal spaces of type $V^+(2n,2)$.
The construction resembles the method for obtaining symplectic spreads in
$V(2n,q)$ from orthogonal spreads in $V^+(2n+2,q)$ when $q$ is even.


title: Two phase transitions induced by a magnetic field in graphite

abstract:
  Different instabilities have been speculated for a three-dimensional electron
gas confined to its lowest Landau level. The phase transition induced in
graphite by a strong magnetic field, and believed to be a Charge Density Wave
(CDW), is the only experimentally established case of such instabilities.
Studying the magnetoresistance in graphite for the first time up to 80 T, we
find that the magnetic field induces two successive phase transitions,
consisting of two distinct ordered states each restricted to a finite field
window. In both states, an energy gap opens up in the out-of-plane conductivity
and coexists with an unexpected in-plane metallicity for a fully gap bulk
system. Such peculiar metallicity may arise as a consequence of edge-state
transport expected to develop in presence of a bulk gap.


title: Noether's theorem for fractional variational problems of variable order

abstract:
  We prove a necessary optimality condition of Euler-Lagrange type for
fractional variational problems with derivatives of incommensurate variable
order. This allows us to state a version of Noether's theorem without
transformation of the independent (time) variable. Considered derivatives of
variable order are defined in the sense of Caputo.


title:
Upper critical magnetic field in K0.83Fe1.83Se2 and Eu0.5K0.5Fe2As2
  single crystals

abstract:
  The H-T phase diagrams of single crystalline electron-doped K0.83Fe1.83Se2
(KFS1), K0.8Fe2Se2 (KFS2) and hole-doped Eu0.5K0.5Fe2As2 (EKFA) have been
deduced from tunnel diode oscillator-based contactless measurements in pulsed
magnetic fields up to 57 T for the inter-plane (H//c) and in-plane (H//ab)
directions. The temperature dependence of the upper critical magnetic field
Hc2(T) relevant to EFKA is accounted for by the Pauli model including an
anisotropic Pauli paramagnetic contribution (\mu_BHp=114 T for H//ab and 86 T
for H//c). This is also the case of KFS1 and KFS2 for H//ab whereas a
significant upward curvature, accounted for by a two-gap model, is observed for
H//c. Despite the presence of antiferromagnetic lattice order within the
superconducting state of the studied compounds, no influence of magnetic
ordering on the temperature dependence of Hc2(T) is observed.


title: Consensus for Quantum Networks: From Symmetry to Gossip Iterations

abstract:
  This paper extends the consensus framework, widely studied in the literature
on distributed computing and control algorithms, to networks of quantum
systems. We define consensus situations on the basis of invariance and symmetry
properties, finding four different probabilistic generalizations of classical
consensus states. We then extend the gossip consensus algorithm to the quantum
setting and prove its convergence properties, showing how it converges to
symmetric states while preserving the expectation of permutation-invariant
global observables.


title:
Using Smartphones as a Proxy for Forensic Evidence contained in Cloud
  Storage Services

abstract:
  Cloud storage services such as Dropbox, Box and SugarSync have been embraced
by both individuals and organizations. This creates an environment that is
potentially conducive to security breaches and malicious activities. The
investigation of these cloud environments presents new challenges for the
digital forensics community. It is anticipated that smartphone devices will
retain data from these storage services. Hence, this research presents a
preliminary investigation into the residual artifacts created on an iOS and
Android device that has accessed a cloud storage service. The contribution of
this paper is twofold. First, it provides an initial assessment on the extent
to which cloud storage data is stored on these client-side devices. This view
acts as a proxy for data stored in the cloud. Secondly, it provides
documentation on the artifacts that could be useful in a digital forensics
investigation of cloud services.


title: Nori's Fundamental Group over a non Algebraically Closed Field

abstract:
  In this note we generalize Nori's definition of the fundamental group scheme
from a rational point to an arbitrary base point so that when we take $X$ to be
a field $k$ and the point to be $k\subseteq \bar{k}$ we still get a non trivial
group scheme which is similar to the absolute Galois group ${\rm
Gal}(\bar{k}/k)$. Then we try to understand the group scheme at various levels.


title: Performances of a large mass ZnSe bolometer to search for rare events

abstract:
  Scintillating bolometers of ZnSe are the baseline choice of the LUCIFER
experiment, whose aim is to observe the neutrinoless double beta decay of 82Se.
The independent read-out of the heat and scintillation signals allows to
identify and reject alpha particle interactions, the dominant background source
for bolometric detectors. In this paper we report the performances of a ZnSe
crystal operated within the LUCIFER R&D. We measured the scintillation yield,
the energy resolution and the background in the energy region where the signal
from neutrinoless double beta decay of 82Se is expected with an exposure of 9.4
kg x days. With a newly developed analysis algorithm we improved the rejection
of alpha events, and we estimated the increase in energy resolution obtained by
the combination of the heat and light signals. For the first time we measured
the light emitted by nuclear recoils, and found it to be compatible with zero.
We conclude that the discrimination of nuclear recoils from beta/gamma
interactions in the WIMPs energy region is possible, but low-noise light
detectors are needed.


title: Cliquewidth and Knowledge Compilation

abstract:
  In this paper we study the role of cliquewidth in succinct representation of
Boolean functions. Our main statement is the following: Let $Z$ be a Boolean
circuit having cliquewidth $k$. Then there is another circuit $Z^*$ computing
the same function as $Z$ having treewidth at most $18k+2$ and which has at most
$4|Z|$ gates where $|Z|$ is the number of gates of $Z$. In this sense,
cliquewidth is not more `powerful' than treewidth for the purpose of
representation of Boolean functions. We believe this is quite a surprising fact
because it contrasts the situation with graphs where an upper bound on the
treewidth implies an upper bound on the cliquewidth but not vice versa.
  We demonstrate the usefulness of the new theorem for knowledge compilation.
In particular, we show that a circuit $Z$ of cliquewidth $k$ can be compiled
into a Decomposable Negation Normal Form ({\sc dnnf}) of size
$O(9^{18k}k^2|Z|)$ and the same runtime. To the best of our knowledge, this is
the first result on efficient knowledge compilation parameterized by
cliquewidth of a Boolean circuit.


title:
Instantaneous mean-variance hedging and instantaneous Sharpe ratio
  pricing in a regime-switching financial model, with applications to
  equity-linked claims

abstract:
  We study hedging and pricing of unattainable contingent claims in a
non-Markovian regime-switching financial model. Our financial market consists
of a bank account and a risky asset whose dynamics are driven by a Brownian
motion and a multivariate counting process with stochastic intensities. The
interest rate, drift, volatility and intensities fluctuate over time and, in
particular, they depend on the state (regime) of the economy which is modelled
by the multivariate counting process. Hence, we can allow for stressed market
conditions. We assume that the trajectory of the risky asset is continuous
between the transition times for the states of the economy and that the value
of the risky asset jumps at the time of the transition. We find the hedging
strategy which minimizes the instantaneous mean-variance risk of the hedger's
surplus and we set the price so that the instantaneous Sharpe ratio of the
hedger's surplus equals a predefined target. We use Backward Stochastic
Differential Equations. Interestingly, the instantaneous mean-variance hedging
and instantaneous Sharpe ratio pricing can be related to no-good-deal pricing
and robust pricing and hedging under model ambiguity. We discuss key properties
of the optimal price and the optimal hedging strategy. We also use our results
to price and hedge mortality-contingent claims with financial components
(equity-linked insurance claims) in a combined insurance and regime-switching
financial model.


title: Geodesic study of a charged black hole

abstract:
  The behavior of the timelike and null geodesics of charged E.
Ay$\acute{o}$n-Beato and A. Garcia (ABG) black hole are investigated. For
circular and radial geodesics, we investigate all the possible motions by
plotting the effective potentials for different parameters. In conclusion, we
have shown that there is no phenomenon of \textit{superradiance} in this case.


title:
Luminosity dependent star-formation history of S0 galaxies: evidence
  from GALEX-SDSS-2MASS-WISE colours

abstract:
  We combine UV/Optical/near-IR/mid-IR data on a sample of ~240 S0 galaxies to
examine various star formation related processes in them. We split the sample
into bright and faint S0 galaxies based on their K band luminosity. Comparing
the FUV-NUV versus NUV-K color-color diagram with a Simple Stellar Population
(SSP) model shows that ellipticals and bright S0 galaxies are dominated by a
stellar population of age > 10^9 years while faint S0 galaxies may contain
stars as young as 10^8 years, providing evidence for relatively recent star
formation activity. The strength of the 4000A break is also systematically
higher in brighter S0 galaxies, again indicating the presence of an old stellar
population. Their mid-IR colours indicate that bright S0 colours are like those
of ellipticals while faint S0 colours are more like spirals. All these
observations are consistent with a scenario in which low-luminosity S0 galaxies
likely formed by the stripping of gas from the discs of late-type spiral
galaxies, which in turn formed their pseudo bulges through secular evolution
processes, possibly involving multiple episodes of star formation. On the other
hand, more luminous S0 galaxies likely formed the bulk of their stars at early
epochs, similar to the star formation in elliptical galaxies, and are
characterised by an old coeval stellar population and classical bulge


title: Sparsity-Exploiting Anchor Placement for Localization in Sensor Networks

abstract:
  We consider the anchor placement problem in localization based on one-way
ranging, in which either the sensor or the anchors send the ranging signals.
The number of anchors deployed over a geographical area is generally sparse,
and we show that the anchor placement can be formulated as the design of a
sparse selection vector. Interestingly, the case in which the anchors send the
ranging signals, results in a joint ranging energy optimization and anchor
placement problem. We make abstraction of the localization algorithm and
instead use the Cram\'er-Rao lower bound (CRB) as the performance constraint.
The anchor placement problem is formulated as an elegant convex optimization
problem which can be solved efficiently.


title: Drinfeld modular polynomials in higher rank II: Kronecker congruences

abstract:
  This is a sequel to the paper [F. Breuer, H.-G. R\"uck, Drinfeld modular
polynomials in higher rank, J. Number Theory 129 (2009), 59-83.], in which we
introduced Drinfeld modular polynomials of higher rank, using an analytic
construction. These polynomials relate the isomorphism invariants of Drinfeld
F_q[T]-modules of rank r\geq 2 linked by isogenies of a specified type. In the
current paper, we give an algebraic construction of greater generality, and
prove a generalization of the Kronecker congruences relations, which describe
what happens when modular polynomials associated to P-isogenies are reduced
modulo a prime P. We also correct an error in [loc. cit.].


title:
An improved semantic similarity measure for document clustering based on
  topic maps

abstract:
  A major computational burden, while performing document clustering, is the
calculation of similarity measure between a pair of documents. Similarity
measure is a function that assigns a real number between 0 and 1 to a pair of
documents, depending upon the degree of similarity between them. A value of
zero means that the documents are completely dissimilar whereas a value of one
indicates that the documents are practically identical. Traditionally,
vector-based models have been used for computing the document similarity. The
vector-based models represent several features present in documents. These
approaches to similarity measures, in general, cannot account for the semantics
of the document. Documents written in human languages contain contexts and the
words used to describe these contexts are generally semantically related.
Motivated by this fact, many researchers have proposed seman-tic-based
similarity measures by utilizing text annotation through external thesauruses
like WordNet (a lexical database). In this paper, we define a semantic
similarity measure based on documents represented in topic maps. Topic maps are
rapidly becoming an industrial standard for knowledge representation with a
focus for later search and extraction. The documents are transformed into a
topic map based coded knowledge and the similarity between a pair of documents
is represented as a correlation between the common patterns (sub-trees). The
experimental studies on the text mining datasets reveal that this new
similarity measure is more effective as compared to commonly used similarity
measures in text clustering.


title: The order of principal congruences of a semimodular lattice

abstract:
  This paper has been withdrawn by the authors due to a crucial computational
error. In this paper we deal with the finite case. We prove that a finite
bounded ordered set can be represented as the order of principal congruences of
a finite \emph{semimodular lattice}.


title:
Montel's Theorem and subspaces of distributions which are
  $\Delta^m$-invariant

abstract:
  We study the finite dimensional spaces $V$ which are invariant under the
action of the finite differences operator $\Delta_h^m$. Concretely, we prove
that if $V$ is such an space, there exists a finite dimensional translation
invariant space $W$ such that $V\subseteq W$. In particular, all elements of
$V$ are exponential polynomials. Furthermore, $V$ admits a decomposition
$V=P\oplus E$ with $P$ a space of polynomials and $E$ a translation invariant
space. As a consequence of this study, we prove a generalization of a famous
result by P. Montel which states that, if $f:\mathbb{R}\to \mathbb{C}$ is a
continuous function satisfying $\Delta_{h_1}^mf(t) = \Delta_{h_2}^mf(t)=0$ for
all $t\in\mathbb{R}$ and certain $h_1,h_2\in\mathbb{R}\setminus\{0\}$ such that
$h_1/h_2\not\in\mathbb{Q}$, then $f(t)=a_0+a_1t+\cdots+a_{m-1}t^{m-1}$ for all
$t\in\mathbb{R}$ and certain complex numbers $a_0,a_1,\cdots,a_{m-1}$. We
demonstrate, with quite different arguments, the same result not only for
ordinary functions $f(t)$ but also for complex valued distributions. Finally,
we also consider in this paper the subspaces $V$ which are
$\Delta_{h_1h_2\cdots h_m}$-invariant for all $h_1,\cdots,h_m\in\mathbb{R}$.


title: Topological constraints in magnetic field relaxation

abstract:
  Stability and reconnection of magnetic fields play a fundamental role in
natural and man-made plasma. In these applications the field's topology
determines the stability of the magnetic field. Here I will describe the
importance of one topology quantifier, the magnetic helicity, which impedes any
free decay of the magnetic energy. Further constraints come from the fixed
point index which hinders the field to relax into the Taylor state.


title: Boundary values, random walks and $\ell^p$-cohomology in degree one

abstract:
  The vanishing of reduced $\ell^2$-cohomology for amenable groups can be
traced to the work of Cheeger & Gromov. The subject matter here is reduced
$\ell^p$-cohomology for $p \in ]1,\infty[$, particularly its vanishing. Results
showing its triviality are obtained, for example: when $p \in ]1,2]$ and $G$ is
amenable; when $p \in ]1,\infty[$ and $G$ is Liouville (in particular, of
intermediate growth).
  This is done by answering a question of Pansu assuming the graph satisfies an
isoperimetric profile. Namely, the triviality of the reduced
$\ell^p$-cohomology is equivalent to the absence of non-constant bounded
(equivalently, not necessarily bounded) harmonic functions with gradient in
$\ell^q$ ($q$ depends on the profile). In particular, one reduces questions of
non-linear analysis ($p$-harmonic functions) to linear ones (harmonic functions
with a restrictive growth condition).


title: Device-Free Person Detection and Ranging in UWB Networks

abstract:
  We present a novel device-free stationary person detection and ranging
method, that is applicable to ultra-wide bandwidth (UWB) networks. The method
utilizes a fixed UWB infrastructure and does not require a training database of
template waveforms. Instead, the method capitalizes on the fact that a human
presence induces small low-frequency variations that stand out against the
background signal, which is mainly affected by wideband noise. We analyze the
detection probability, and validate our findings with numerical simulations and
experiments with off-the-shelf UWB transceivers in an indoor environment.


title: An aspect of particles' spatial competition

abstract:
  The branching random walk is shown to be monotone decreasing in ascending
direction of integer lattices as a corollary of an observation in regard to the
lineage of particles from antisymmetric initial states, and a related property
of percolation paths on the usual oriented lattices is also given.


title:
Aristotelian Electrodynamics solves the Pulsar: Lower Efficiency of
  Strong Pulsars

abstract:
  In Aristotelian Electrodynamics (AE), due to radiation over-damping, the
velocity rather than the acceleration of a charge is determined by the local
electromagnetic field. Treating electrons and positrons separately, AE seems to
give a faithful description of the flow of charges in a pulsar magnetosphere.
AE might allow to calculate the pulsar emission in full detail, at all energies
except the radio.
  But AE is not a full theory -- the plasma production processes must be added.
Here we show that the pulsar magnetosphere and the resulting emission are
sensitive to the plasma production rate near the light cylinder. In strong
pulsars (high production rate, due to photon-photon collisions), the number of
field lines closing beyond the light cylinder decreases. This reduces both the
pulsar efficiency (the ratio of the pulsed bolometric luminosity to the
spin-down power) and the characteristic photon energy, in overall agreement
with the Fermi data.
  For weak pulsars (low production rate), our numerical implementation of AE
works stably and seems to be ready to calculate the lightcurves and spectra.
But for strong pulsars, the code (included) needs improvement or better
understanding.


title:
Collisionless shock formation, spontaneous electromagnetic fluctuations
  and streaming instabilities

abstract:
  Collisionless shocks are ubiquitous in astrophysics and in the lab. Recent
numerical simulations and experiments have shown how they can arise from the
encounter of two collisionless plasma shells. When the shells interpenetrate,
the overlapping region turns unstable, triggering the shock formation. As a
first step towards a microscopic understanding of the process, we analyze here
in detail the initial instability phase. On the one hand, 2D relativistic PIC
simulations are performed where two symmetric initially cold pair plasmas
collide. On the other hand, the instabilities at work are analyzed, as well as
the field at saturation and the seed field which gets amplified. For mildly
relativistic motions and onward, Weibel modes govern the linear phase. We
derive an expression for the duration of the linear phase in good agreement
with the simulations. This saturation time constitutes indeed a lower-bound for
the shock formation time.


title:
Median and mean of the Supremum of $L^2$ normalized random holmorphic
  fields

abstract:
  We prove that the expected value and median of the supremum of $L^2$
normalized random holomorphic fields of degree $n$ on $m$-dimensional K\"ahler
manifolds are asymptotically of order $\sqrt{m\log n}$. This improves the prior
result of Shiffman-Zelditch (arXiv:math/0303335) that the upper bound of the
media is of order $\sqrt{\log n}$
  The estimates are based on the entropy methods of Dudley and Sudakov combined
with a precise analysis of the relevant pseudo-metric and its covering numbers,
which can be precisely evaluated using off-diagonal asymptotics of Bergman
kernels. Recent work of the authors on the value distribution of these fields
are also used to get precise constants.


title:
Lepton Flavor and Number Conservation, and Physics Beyond the Standard
  Model

abstract:
  The physics responsible for neutrino masses and lepton mixing remains
unknown. More experimental data are needed to constrain and guide possible
generalizations of the standard model of particle physics, and reveal the
mechanism behind nonzero neutrino masses. Here, the physics associated with
searches for the violation of lepton-flavor conservation in charged-lepton
processes and the violation of lepton-number conservation in nuclear physics
processes is summarized. In the first part, several aspects of charged-lepton
flavor violation are discussed, especially its sensitivity to new particles and
interactions beyond the standard model of particle physics. The discussion
concentrates mostly on rare processes involving muons and electrons. In the
second part, the status of the conservation of total lepton number is
discussed. The discussion here concentrates on current and future probes of
this apparent law of Nature via searches for neutrinoless double beta decay,
which is also the most sensitive probe of the potential Majorana nature of
neutrinos.


title:
Probing Dynamics of Electron Acceleration with Radio and X-ray
  Spectroscopy, Imaging, and Timing in the 2002 Apr 11 Solar Flare

abstract:
  Based on detailed analysis of radio and X-ray observations of a flare on 2002
April 11 augmented by realistic 3D modeling, we have identified a radio
emission component produced directly at the flare acceleration region. This
acceleration region radio component has distinctly different (i) spectrum, (ii)
light curves, (iii) spatial location, and, thus, (iv) physical parameters from
those of the separately identified, trapped or precipitating electron
components. To derive evolution of physical parameters of the radio sources we
apply forward fitting of the radio spectrum time sequence with the
gyrosynchrotron source function with 5 to 6 free parameters. At the stage when
the contribution from the acceleration region dominates the radio spectrum, the
X-ray- and radio- derived electron energy spectral indices agree well with each
other. During this time the maximum energy of the accelerated electron spectrum
displays a monotonic increase with time from ~ 300 keV to ~ 2 MeV over roughly
one minute duration indicative of an acceleration process in the form of growth
of the power-law tail; the fast electron residence time in the acceleration
region is about 2 - 4 s, which is much longer than the time of flight and so
requires a strong diffusion mode there to inhibit free-streaming propagation.
The acceleration region has a relatively strong magnetic field, B ~ 120 G, and
a low thermal density, less than 2x10^9 cm^-3. These acceleration region
properties are consistent with a stochastic acceleration mechanism.


title:
Codimension one partially hyperbolic diffeomorphisms with a uniformly
  compact center foliation

abstract:
  We consider a partially hyperbolic C1-diffeomorphism f on a smooth compact
manifold M with a uniformly compact f-invariant center foliation. We show that
if the unstable bundle is one-dimensional and oriented, then the holonomy of
the center foliation vanishes everywhere, the quotient space of the center
foliation is a torus and f induces a hyperbolic automorphism on it, in
particular, f is centrally transitive. We actually obtain further interesting
results without restrictions on the unstable, stable and center dimension: we
prove a kind of spectral decomposition for the chain recurrent set of the
quotient dynamics, and we establish the existence of a holonomy invariant
family of measures on the unstable leaves (Margulis measure).


title:
On the ladder operators and nonclassicality of generalized coherent
  state associated with a particle in an infinite square well

abstract:
  In this paper the factorization method is used in order to obtain the
eigenvalues and eigenfunctions of a quantum particle confined in a
one-dimensional infinite well. The output results from the mentioned approach
allows us to explore an appropriate new pair of raising and lowering operators
corresponding to the physical system under consideration. From the symmetrical
considerations, the connection between the obtained ladder operators with
$su(1,1)$ Lie algebra is explicitly established. Next, after the construction
of Barut-Girardello and Gilmore-Perelomov representations of coherent states
associated with the considered system, some of their important properties like
the resolution of the identity including a few nonclassical features are
illustrated in detail. Finally, a theoretical scheme for generation of the
Gilmore-Perelomov type of coherent state via a generalized Janes-Cummings model
is proposed.


title:
Spectral, stochastic and curvature estimates for submanifolds of highly
  negative curved spaces

abstract:
  We prove spectral, stochastic and mean curvature estimates for complete
$m$-submanifolds $\varphi \colon M \to N$ of $n$-manifolds with a pole $N$ in
terms of the comparison isoperimetric ratio $I_{m}$ and the extrinsic radius
$r_\varphi\leq \infty$. Our proof holds for the bounded case $r_\varphi<
\infty$, recovering the known results, as well as for the unbounded case
$r_{\varphi}=\infty$. In both cases, the fundamental ingredient in these
estimates is the integrability over $(0, r_\varphi)$ of the inverse
$I_{m}^{-1}$ of the comparison isoperimetric radius. When $r_{\varphi}=\infty$,
this condition is guaranteed if $N$ is highly negatively curved.


title:
The idempotents of the TL_n-modules \otimes^nC^2 in terms of elements of
  U_qsl_2

abstract:
  The vector space \otimes^nC^2 upon which the XXZ Hamilonian with n spins acts
bears the structure of a module over both the Temperley-Lieb algebra
TL_n(\beta=q+1/q) and the quantum algebra U_qsl_2. The decomposition of
\otimes^nC^2 as a U_qsl_2-module was first described by Rosso [23], Lusztig
[15] and Pasquier and Saleur [20] and that as a TL_n-module by Martin [17] (see
also Read and Saleur [21] and Gainutdinov and Vasseur [9]). For q generic, i.e.
not a root of unity, the TL_n-module \otimes^nC^2 is known to be a sum of
irreducible modules. We construct the projectors (idempotents of the algebra of
endomorphisms of \otimes^nC^2) onto each of these irreducible modules as linear
combinations of elements of U_qsl_2. When q=q_c is a root of unity, the
TL_n-module \otimes^nC^2 (with n large enough) can be written as a direct sum
of indecomposable modules that are not all irreducible. We also give the
idempotents projecting onto these indecomposable modules. Their expression now
involve some new generators, whose action on \otimes^nC^2 is that of the
divided powers (S^\pm)^{(r)}=\lim_{q\to q_c} (S^\pm)^r/[r]!.


title: Quantum quenches and work distributions in ultra-low-density systems

abstract:
  We present results on quantum quenches in systems with a fixed number of
particles in a large region. We show that the typical differences between local
and global quenches present in systems with regular thermodynamic limit are
lacking in this low-density limit. In particular, we show that in this limit
local quenches may not lead to equilibration to the new ground state, and that
global quenches can have power-law work distributions ("edge singularities")
typically associated with local quenches for finite-density systems. We also
show that this regime allows for large edge singularity exponents beyond that
allowed by the constraints of the usual thermodynamic limit. This
large-exponent singularity has observable consequences in the time evolution,
leading to a distinct intermediate power-law regime in time. We demonstrate
these results first using local quantum quenches in a low-density Kondo-like
system, and additionally through global and local quenches in Bose-Hubbard,
Aubry-Andre, and hard-core boson systems in the low-density regime.


title: The configuration space and principle of virtual work for rough bodies

abstract:
  In the setting of an $n$-dimensional Euclidean space, the duality between
velocity fields on the class of admissible bodies and Cauchy fluxes is studied
using tools from geometric measure theory. A generalized Cauchy flux theory is
obtained for sets whose measure theoretic boundaries may be as irregular as
flat $(n-1)$-chains. Initially, bodies are modeled as normal $n$-currents
induced by sets of finite perimeter. A configuration space comprising Lipschitz
embeddings induces virtual velocities given by locally Lipschitz mappings. A
Cauchy flux is defined as a real valued function on the Cartesian product of
$(n-1)$-currents and locally Lipschitz mappings. A version of Cauchy's
postulates implies that a Cauchy flux may be uniquely extended to an $n$-tuple
of flat $(n-1)$-cochains. Thus, the class of admissible bodies is extended to
include flat $n$-chains and a generalized form of the principle of virtual
power is presented. Wolfe's representation theorem for flat cochains enables
the identification of stress as an $n$-tuple of flat $(n-1)$-forms.


title:
Barut-Girardello and Gilmore-Perelomov coherent states for
  pseudoharmonic oscillator and their nonclassical properties: factorization
  method

abstract:
  In this paper we try to introduce the ladder operators associated with the
pseudoharmonic oscillator, after solving the corresponding Schr\"{o}dinger
equation by using the factorization method. The obtained generalized raising
and lowering operators naturally lead us to the Dirac representation space of
the system which is very easier to work with, in comparison to the functional
Hilbert space. The SU(1,1) dynamical symmetry group associated with the
considered system is exactly established through investigating the fact that
the deduced operators satisfy appropriate commutation relations. This result
enables us to construct two important and distinct classes of Barut-Girardello
and Gilmore-Perelomov coherent states associated with the system. Finally,
their identities as the most important task are exactly resolved and some of
their nonclassical properties are illustrated, numerically.


title:
Entanglement dynamics and position-momentum entropic uncertainty
  relation of a $\Lambda$-type three-level atom interacting with a two-mode
  cavity field in the presence of nonlinearities

abstract:
  In this paper, the interaction between a $\Lambda$-type three-level atom and
two-mode cavity field is discussed. The detuning parameters and cross-Kerr
nonlinearity are taken into account and it is assumed that atom-field coupling
and Kerr medium to be $f$-deformed. Even though the system seems to be
complicated, the analytical form of the state vector of the entire system for
considered model is exactly obtained. The time evolution of nonclassical
properties such as quantum entanglement and position-momentum entropic
uncertainty relation (entropy squeezing) of the field are investigated. In each
case, the influences of the detuning parameters, generalized Kerr medium and
intensity-dependent coupling on the latter nonclassicality signs are analyzed,
in detail.


title:
Direct Measurement of the Free Energy of Aging Hard-Sphere Colloidal
  Glasses

abstract:
  The nature of the glass transition is one of the most important unsolved
problems in condensed matter physics. The difference between glasses and
liquids is believed to be caused by very large free energy barriers for
particle rearrangements; however so far it has not been possible to confirm
this experimentally. We provide the first quantitative determination of the
free energy for an aging hard-sphere colloidal glass. The determination of the
free energy allows for a number of new insights in the glass transition,
notably the quantification of the strong spatial and temporal heterogeneity in
the free energy. A study of the local minima of the free energy reveals that
the observed variations are directly related to the rearrangements of the
particles. Our main finding is that the probability of particle rearrangements
shows a power law dependence on the free energy changes associated with the
rearrangements, similarly to the Gutenberg-Richter law in seismology.


title: THz radiation by the frequency down-shift of Nd:YAG lasers

abstract:
  The interaction between an intense laser and a relativistic dense electron
beam propagating in the same direction could down-shift the laser frequency.
This process, which can be used to generate a coherent THz radiation, is
theoretically analyzed. With a set of practically relevant parameters, it is
suggested that the radiation energy could reach the order of 1 mJ per shot in
the duration of 100 pico-second, or the temporal radiation power of 10 MW.


title: von-Neumann and Birkhoff ergodic theorems for negatively curved groups

abstract:
  We prove maximal inequalities for concentric ball and spherical shell
averages on a general Gromov hyperbolic group, in arbitrary probability
preserving actions of the group. Under an additional condition, satisfied for
example by all groups acting isometrically and properly discontinuously on
CAT(-1) spaces, we prove a pointwise ergodic theorem with respect to a sequence
of probability measures supported on concentric spherical shells.


title: On Linear Spaces of Polyhedral Meshes

abstract:
  Polyhedral meshes (PM) - meshes having planar faces - have enjoyed a rise in
popularity in recent years due to their importance in architectural and
industrial design. However, they are also notoriously difficult to generate and
manipulate. Previous methods start with a smooth surface and then apply
elaborate meshing schemes to create polyhedral meshes approximating the
surface. In this paper, we describe a reverse approach: given the topology of a
mesh, we explore the space of possible planar meshes with that topology.
  Our approach is based on a complete characterization of the maximal linear
spaces of polyhedral meshes contained in the curved manifold of polyhedral
meshes with a given topology. We show that these linear spaces can be described
as nullspaces of differential operators, much like harmonic functions are
nullspaces of the Laplacian operator. An analysis of this operator provides
tools for global and local design of a polyhedral mesh, which fully expose the
geometric possibilities and limitations of the given topology.


title: THz radiation by beating Langmuir waves

abstract:
  An intense terahertz (THz) radiation generated by the beating of two Langmuir
waves, which are excited by the forward Raman scattering, is analyzed
theoretically. The radiation energy per shot can be as high as 0.1 J, with the
duration of 10 pico-second. Appropriate plasma density and the laser
characteristics are examined.


title: Quasi-particle approach for general lattice Hamiltonians

abstract:
  In many condensed-matter systems, it is very useful to introduce a
quasi-particle approach, which is based on some sort of linearization around a
suitable background state. In order to be a systematic and controlled
approximation, this linearization should be justified by an expansion into
powers of some small control parameter. Here, we present a method for general
lattice Hamiltonians with large coordination numbers Z >> 1, which is based on
an expansion into powers of 1/Z. In order to demonstrate the generality of our
method, we apply it to various spin systems, as well as the Bose and Fermi
Hubbard model.


title: Correspondences between projective planes

abstract:
  We characterize integral homology classes of the product of two projective
planes which are representable by a subvariety.