title:
Velocities: mean, average and instantaneous in uniform accelerated
  motion, some pedagogical comments

abstract:
  The relation among instantaneous, mean and average velocities in
one-dimensional motion with constant acceleration is studied. It was shown that
the instant velocity evaluated in the time $t_{p}=\left(t_2+t_1\right)/2$ is
similar to the mean and average velocities evaluated between the times $t_1$
and $t_2$. The reason for relations illustrated before were shown in detail.
Also, the results obtained were used to propose a pedagogical strategy in order
to study the one-dimensional motion with constant acceleration as a natural
extension of one-dimensional motion with constant velocity.


title:
Minimum Energy Source Coding for Asymmetric Modulation with Application
  to RFID

abstract:
  Minimum energy (ME) source coding is an effective technique for efficient
communication with energy-constrained devices, such as sensor network nodes. In
this paper, the principles of generalized ME source coding is developed that is
broadly applicable. Two scenarios - fixed and variable length codewords - are
analyzed. The application of this technique to RFID systems where ME source
coding is particularly advantageous due to the asymmetric nature of data
communications is demonstrated, a first to the best of our knowledge.


title: Property A for coarse spaces

abstract:
  Property A introduced by Guoliang Yu is an amenability-type property for
metric spaces. In this article, we study property A for uniformly locally
finite coarse spaces. Main examples of coarse spaces are a metric space, a set
equipped with a discrete group action, and a sequence of finitely generated
groups. The purpose of this article is to give complete proofs to related basic
facts.


title: Riemann zeta zeros and prime number spectra in quantum field theory

abstract:
  The Riemann hypothesis states that all nontrivial zeros of the zeta function
lie in the critical line $\Re(s)=1/2$. Hilbert and P\'olya suggested that one
possible way to prove the Riemann hypothesis is to interpret the nontrivial
zeros in the light of spectral theory. Following this approach, we discuss a
necessary condition that such a sequence of numbers should obey in order to be
associated with the spectrum of a linear differential operator of a system with
countably infinite number of degrees of freedom described by quantum field
theory. The sequence of nontrivial zeros is zeta regularizable. Then,
functional integrals associated with hypothetical systems described by
self-adjoint operators whose spectra is given by this sequence can be
constructed. However, if one considers the same situation with primes numbers,
the associated functional integral cannot be constructed, due to the fact that
the sequence of prime numbers is not zeta regularizable. Finally, we extend
this result to sequences whose asymptotic distributions are not "far away" from
the asymptotic distribution of prime numbers.


title: The Relation Between Diagrams of a Knot and Its Unknotting Number

abstract:
  The unknotting number is the classical invariant of a knot. However, its
determination is difficult in general. To obtain the unknotting number from
definition one has to investigate all possible diagrams of the knot. We tried
to show the unknotting number can be obtained from any one diagram of the knot.
To do this we tried to prove the unknotting number is not changed under
Riedemiester moves, but such a proposition is not correct. Reidemeister II move
can change unknotting number. See Nakanishi-Bleiler example. So this article is
withdrawn.


title:
Energy Efficient Cooperative Strategies for Relay-Assisted Downlink
  Cellular Systems, Part I: Theoretical Framework

abstract:
  The impact of cognition on the energy efficiency of a downlink cellular
system in which multiple relays assist the transmission of the base station is
considered. The problem is motivated by the practical importance of
relay-assisted solutions in mobile networks, such as LTE-A, in which
cooperation among relays holds the promise of greatly improving the energy
efficiency of the system. We study the fundamental tradeoff between the power
consumption at the base station and the level of cooperation and cognition at
the relay nodes. By distributing the same message to multiple relays, the base
station consumes more power but it enables cooperation among the relays, thus
making the transmission between relays to destination a multiuser cognitive
channel. Cooperation among the relays allows for a reduction of the power used
to transmit from the relays to the end users due to interference management and
the coherent combining gains. These gain are present even in the case of
partial or unidirectional transmitter cooperation, which is the case in
cognitive channels such as the cognitive interference channel and the
interference channel with a cognitive relay. We therefore address the problem
of determining the optimal level of cooperation at the relays which results in
the smallest total power consumption when accounting for the power reduction
due to cognition. A practical design examples and numerical simulation are
presented in a companion paper (part II).


title:
Spin Torque on Magnetic Textures Coupled to the Surface of a
  Three-Dimensional Topological Insulator

abstract:
  We investigate theoretically the spin torque and magnetization dynamic in a
thin ferromagnetic (FM) layer with spatially varying magnetization. The FM
layer is deposited on the surface of a topological insulator (TI). In the limit
of the adiabatic relaxation of electron spin along the magnetization, the
interaction between the exchange interaction and the Rashba-like surface
texture of a TI yields a topological gauge field. Under the gauge field and an
applied current, spin torque is induced according to the direction of the
current. We derived the corresponding effective anisotropy field and hence the
modified Landau-Lifshitz-Gilbert equation, which describes the spin torque and
the magnetization dynamic. In addition, we study the effective field for
exemplary magnetic textures, such as domain wall, skyrmion, and vortex
configurations. The estimated strength of the effective field is comparable to
the switching fields of typical FM materials, and hence can significantly
influence the dynamics of the FM layer.


title: A Massively Parallel Associative Memory Based on Sparse Neural Networks

abstract:
  Associative memories store content in such a way that the content can be
later retrieved by presenting the memory with a small portion of the content,
rather than presenting the memory with an address as in more traditional
memories. Associative memories are used as building blocks for algorithms
within database engines, anomaly detection systems, compression algorithms, and
face recognition systems. A classical example of an associative memory is the
Hopfield neural network. Recently, Gripon and Berrou have introduced an
alternative construction which builds on ideas from the theory of error
correcting codes and which greatly outperforms the Hopfield network in
capacity, diversity, and efficiency. In this paper we implement a variation of
the Gripon-Berrou associative memory on a general purpose graphical processing
unit (GPU). The work of Gripon and Berrou proposes two retrieval rules,
sum-of-sum and sum-of-max. The sum-of-sum rule uses only matrix-vector
multiplication and is easily implemented on the GPU. The sum-of-max rule is
much less straightforward to implement because it involves non-linear
operations. However, the sum-of-max rule gives significantly better retrieval
error rates. We propose a hybrid rule tailored for implementation on a GPU
which achieves a 880-fold speedup without sacrificing any accuracy.


title:
Coulomb-oscillator explanation of striped STM images of superconductive
  copper oxides

abstract:
  Asymmetric scanning tunneling microscopy (STM) of the CuO2 plane of
Ca2-xNaxCuO2Cl2, x = 0.125, shows a square domain structure with edge length
four times the compound's lattice constant a0 (Cu-O-Cu distance). The domain
structure is a direct consequence of the 4a0 by 4a0 superlattice formed by
vertical Na+ pairs (oriented parallel to the crystal's c axis) that substitute
Ca2+ ions. The surrounding O2- ions are displaced away from, and the Cu2+ ions
toward the Na+ pairs. Contrary to the fourfold symmetry of the CuO2 plane, the
stable displacement configuration has a twofold symmetry, dominated by large
and, respectively, small displacement of opposite O2- ions being nearest
neighbors to each vertical Na+ pair. The ion displacements give rise to
sufficient squeeze of certain O2- ions that, by the Coulomb-oscillator model of
superconductivity, prevents lateral overswing of their excited 3s electrons.
The axial 3s oscillations are predominantly oriented in the directions of O2-
ion displacements. The observed ladder pattern in the domains provides a direct
imaging of the 3s Coulomb oscillators. The 'sidepieces' of the ladders
correspond to long unidirectional pathways for 3s electrons in the CuO2 plane.
They account for superconductivity. The findings lend support to the validity
of the Coulomb-oscillator model of superconductivity.


title:
Energy Efficient Cooperative Strategies for Relay-Assisted Downlink
  Cellular Systems Part II: Practical Design

abstract:
  In a companion paper [1], we present a general approach to evaluate the
impact of cognition in a downlink cellular system in which multiple relays
assist the transmission of the base station. This approach is based on a novel
theoretical tool which produces transmission schemes involving rate-splitting,
superposition coding and interference decoding for a network with any number of
relays and receivers. This second part focuses on a practical design example
for a network in which a base station transmits to three receivers with the aid
of two relay nodes. For this simple network, we explicitly evaluate the impact
of relay cognition and precisely characterize the trade offs between the total
energy consumption and the rate improvements provided by relay cooperation.
These closedform expressions provide important insights on the role of
cognition in larger networks and highlights interesting interference management
strategies. We also present a numerical simulation setup in which we fully
automate the derivation of achievable rate region for a general relay-assisted
downlink cellular network. Our simulations clearly show the great advantages
provided by cooperative strategies at the relays as compared to the
uncoordinated scenario under varying channel conditions and target rates. These
results are obtained by considering a large number of transmission strategies
for different levels of relay cognition and numerically determining one that is
the most energy efficient. The limited computational complexity of the
numerical evaluations makes this approach suitable for the optimization of
transmission strategies for larger networks.


title:
An effective gauge-Higgs operators analysis of new physics associated
  with the Higgs

abstract:
  We study the new physics(NP) related to the recent discovered 125 GeV Higgs
by employing an important subset of the standard model(SM) gauge invariant
dimension-six operators constructed by the the SM Higgs and gauge fields.
Explicitly, we perform a model-independent study on the production and decays
of the Higgs, the electric dipole moments(EDM) of the neutron and the electron,
and we take into account the anomalous magnetic dipole moments of muon and
electron as well.
  We find that, even all Higgs decay channels agree with the SM predictions,
the SM theoretical uncertainties provide a lot of room to host NP associated
with the 125 GeV boson. A linear relation is revealed in our numerical study
that $\mu_{ZZ}\simeq \mu_{WW}$ and $ 0.6 \lesssim \mu_{ZZ,WW} \lesssim 1.4$ at
95% CL with or without the EDM's constraints. The neutron and electron EDM's
severely constrain the relevant Wilson coefficients. Therefore the CP violating
components in the $h\rightarrow WW, ZZ$ channels are too small, $\sim{\cal
O}(10^{-5})$, to be detected at LHC. However, we point out that even the parity
of the 125GeV boson has been largely determined to be even in the $h\to ZZ$
channel, one should pay special attention to the potentially large CP violation
in the $h\to \gamma\gamma$ and $h\to \gamma Z$ channels. This should be
seriously checked in the future spin correlation experiments.


title:
Nature of the zero-bias conductance peak associated with Majorana bound
  states in topological phases of semiconductor-superconductor hybrid
  structures

abstract:
  Rashba spin-orbit coupled semiconductor-superconductor hybrid structures in
the presence of Zeeman splitting have emerged as the first experimentally
realizable topological superconductor supporting zero-energy Majorana bound
states. However, recent experimental studies in these hybrid structures are not
in complete agreement with the theoretical predictions, for example, the
observed height of the zero-bias conductance peak (ZBCP) associated with the
Majorana bound states is less than 10% of the predicted quantized value 2e^2/h.
We try to understand the sources of various discrepancies between the recent
experiments and the earlier theories by starting from a microscopic theory and
studying non-equilibrium transport in these systems at arbitrary temperatures
and applied bias voltages. Our approach involves quantum Langevin equations and
non-equilibrium Green's functions. Here we are able to model the tunnel
coupling between the one-dimensional semiconductor-superconductor hybrid
structure and the metallic leads realistically; study the role of tunnel
coupling on the height of the ZBCP and the subgap conductance; predict the
nature of the splitting of the ZBCP with an increasing magnetic field beyond
the critical field; show the behavior of the ZBCP with an increasing
gate-controlled onsite potential; and study the evolution of the full
differential conductance across the topological quantum phase transition. When
the applied magnetic field is quite large compared to the Rashba splitting and
the bulk energy gap is much reduced, we find the ZBCP even for an onsite
potential much larger than the applied magnetic field. The height of the
corresponding ZBCP depends on the tunnel coupling even at zero temperature and
can be much smaller than 2e^2/h.


title: Parameterized Complexity of Discrete Morse Theory

abstract:
  Optimal Morse matchings reveal essential structures of cell complexes which
lead to powerful tools to study discrete geometrical objects, in particular
discrete 3-manifolds. However, such matchings are known to be NP-hard to
compute on 3-manifolds, through a reduction to the erasability problem.
  Here, we refine the study of the complexity of problems related to discrete
Morse theory in terms of parameterized complexity. On the one hand we prove
that the erasability problem is W[P]-complete on the natural parameter. On the
other hand we propose an algorithm for computing optimal Morse matchings on
triangulations of 3-manifolds which is fixed-parameter tractable in the
treewidth of the bipartite graph representing the adjacency of the 1- and
2-simplexes. This algorithm also shows fixed parameter tractability for
problems such as erasability and maximum alternating cycle-free matching. We
further show that these results are also true when the treewidth of the dual
graph of the triangulated 3-manifold is bounded. Finally, we investigate the
respective treewidths of simplicial and generalized triangulations of
3-manifolds.


title:
Extra relativistic degrees of freedom without extra particles using
  Planck data

abstract:
  A recent number of analysis of cosmological data have shown indications for
the presence of extra radiation beyond the standard model at equality and
nucleosynthesis epoch, which has been usually interpreted as an effective
number of neutrinos, Neff > 3.046. In this work we establish the theoretical
basis for a particle physics-motivated model (Bound Dark Matter, BDM) which
explain the need of extra radiation. The BDM model describes dark matter
particles which are relativistic at a scale below a < ac, these particles
acquire mass with an initial velocity, vc, at scales a > ac due to
non-perturbative methods, as protons and neutrons do, this process is described
by a time dependent equation of state, w_bdm(a). Owing to this behavior the
amount of extra radiation change as a function of the scale factor, this entail
that the extra relativistic degrees of freedom Nex may also vary as a function
of the scale factor. This is favored by data at CMB and BBN epochs. We compute
the range of values of the BDM model parameters, xc = ac*vc, that explain the
values obtained for the 4He at BBN and Neff at equality. Combining different
analysis we compute the value xc = 4.13x10^{-5} and vc = 0.37. We conclude that
we can account for the apparent extra neutrino degrees of freedom Nex using a
phase transition in the dark matter with a time dependent equation of state
with no need for introducing extra relativistic particles.


title:
Joint Resource Partitioning and Offloading in Heterogeneous Cellular
  Networks

abstract:
  In heterogeneous cellular networks (HCNs), it is desirable to offload mobile
users to small cells, which are typically significantly less congested than the
macrocells. To achieve sufficient load balancing, the offloaded users often
have much lower SINR than they would on the macrocell. This SINR degradation
can be partially alleviated through interference avoidance, for example time or
frequency resource partitioning, whereby the macrocell turns off in some
fraction of such resources. Naturally, the optimal offloading strategy is
tightly coupled with resource partitioning; the optimal amount of which in turn
depends on how many users have been offloaded. In this paper, we propose a
general and tractable framework for modeling and analyzing joint resource
partitioning and offloading in a two-tier cellular network. With it, we are
able to derive the downlink rate distribution over the entire network, and an
optimal strategy for joint resource partitioning and offloading. We show that
load balancing, by itself, is insufficient, and resource partitioning is
required in conjunction with offloading to improve the rate of cell edge users
in co-channel heterogeneous networks.


title: Topological Insulators in Hexagonal Wurtzite-type Binary Compounds

abstract:
  We propose new topological insulators in hexagonal wurtzite-type binary
compounds based on the first principles calculations. It is found that two
compounds AgI and AuI are three-dimensional topological insulators with a
naturally opened band-gap at Fermi level. From band inversion mechanism point
view, this new family of topological insulators is similar with HgTe, which has
s (Gamma 6) - p (Gamma 8) band inversion. Our results strongly support that the
spin-orbit coupling is not an essential factor to the band inversion mechanism;
on the contrary, it is mainly responsible to the formation of a global band gap
for the studied topological insulators. We further theoretically explore the
feasibility of tuning the topological order of the studied compounds with two
types of strains. The results show that the uniaxial strain can contribute
extremely drastic impacts to the band inversion behavior, which provide an
effective approach to induce topological phase transition.


title: The core of the games with fractional linear utility functions

abstract:
  We consider fractional linear programming production games for the
single-objective and multiobjective cases. We use the method of Chakraborty and
Gupta (2002) in order to transform the fractional linear programming problems
into linear programming problems. A cooperative game is attached and we prove
the non-emptiness of the core by using the duality theory from the linear
programming. In the multiobjective case, we give a characterization of the
Stable outcome of the associate cooperative game, which is balanced. We also
consider the cooperative game associated to an exchange economy with a finite
number of agents.


title:
Observation of infinite-range intensity correlations above, at and below
  the 3D Anderson localization transition

abstract:
  We investigate long-range intensity correlations on both sides of the
Anderson transition of classical waves in a three-dimensional (3D) disordered
material. Our ultrasonic experiments are designed to unambiguously detect a
recently predicted infinite-range C0 contribution, due to local density of
states fluctuations near the source. We find that these C0 correlations, in
addition to C2 and C3 contributions, are significantly enhanced near mobility
edges. Separate measurements of the inverse participation ratio reveal a link
between C0 and the anomalous dimension \Delta_2, implying that C0 may also be
used to explore the critical regime of the Anderson transition.


title: Inductive Hashing on Manifolds

abstract:
  Learning based hashing methods have attracted considerable attention due to
their ability to greatly increase the scale at which existing algorithms may
operate. Most of these methods are designed to generate binary codes that
preserve the Euclidean distance in the original space. Manifold learning
techniques, in contrast, are better able to model the intrinsic structure
embedded in the original high-dimensional data. The complexity of these models,
and the problems with out-of-sample data, have previously rendered them
unsuitable for application to large-scale embedding, however. In this work, we
consider how to learn compact binary embeddings on their intrinsic manifolds.
In order to address the above-mentioned difficulties, we describe an efficient,
inductive solution to the out-of-sample data problem, and a process by which
non-parametric manifold learning may be used as the basis of a hashing method.
Our proposed approach thus allows the development of a range of new hashing
techniques exploiting the flexibility of the wide variety of manifold learning
approaches available. We particularly show that hashing on the basis of t-SNE .


title: Upper bound on the total number of knot $n$-mosaics

abstract:
  Lomonaco and Kauffman introduced a knot mosaic system to give a definition of
a quantum knot system which can be viewed as a blueprint for the construction
of an actual physical quantum system. A knot $n$-mosaic is an $n \times n$
matrix of 11 kinds of specific mosaic tiles representing a knot or a link by
adjoining properly that is called suitably connected. $D_n$ denotes the total
number of all knot $n$-mosaics. Already known is that $D_1=1$, $D_2=2$, and
$D_3=22$. In this paper we establish the lower and upper bounds on $D_n$
$$\frac{2}{275}(9 \cdot 6^{n-2} + 1)^2 \cdot 2^{(n-3)^2} \ \leq \ D_n \ \leq \
\frac{2}{275}(9 \cdot 6^{n-2} + 1)^2 \cdot (4.4)^{(n-3)^2}.$$ and find the
exact number of $D_4 = 2594$.


title:
Correlated many-body calculation to study characteristics of Shannon
  information entropy for ultracold trapped interacting bosons

abstract:
  A correlated many-body calculation is presented to characterize the Shannon
information entropy of trapped interacting bosons. We reformulate the one-body
Shannon information entropy in terms of the one-body probability density. The
minimum limit of the entropy uncertainty relation (EUR) is approached by making
$N$ very small in our numerical work. We examine the effect of correlations in
the calculation of information entropy. Comparison with the mean-field result
shows that the correlated basis function is indeed required to characterize the
important features of the information entropies. We also accurately calculate
the point of critical instability of an attractive BEC, which is in close
agreement with the experimental value. Next we calculate two-body entropies in
position and momentum spaces and study quantum correlations in the attractive
BEC.


title: Ramified coverings of small categories

abstract:
  We introduce a ramified covering of small categories, and we show three
properties of the notion: the Riemann-Hurwitz formula holds for a ramified
covering of finite categories, the zeta function of $C$ divides that of
$\widetilde{C}$ for a ramified covering $\map{P}{\widetilde{C}}{C}$ of finite
categories, and the classifying space of a $d$-fold ramified covering of small
categories is also a $d$-fold ramified covering in the sense of Dold
\cite{Dol86}.


title: Digital three-state adiabatic passage

abstract:
  We explore protocols for three-state adiabatic passage where the tunnel
matrix elements are varied digitally, rather than smoothly as is the case with
conventional adiabatic passage. In particular, we focus on the STIRAP and
related three-state schemes where the control is applied stepwise, with either
equal spaced levels for the tunnel matrix elements or uniform pulse lengths.
Our results show that the evolution typically shows the hallmarks of
conventional adiabatic passage, although with additional resonances exhibiting
no state transfer.


title: Convergence of a data-driven time-frequency analysis method

abstract:
  In a recent paper, Hou and Shi introduced a new adaptive data analysis method
to analyze nonlinear and non-stationary data. The main idea is to look for the
sparsest representation of multiscale data within the largest possible
dictionary consisting of intrinsic mode functions of the form $\{a(t)
\cos(\theta(t))\}$, where $a \in V(\theta)$, $V(\theta)$ consists of the
functions smoother than $\cos(\theta(t))$ and $\theta'\ge 0$. This problem was
formulated as a nonlinear $L^0$ optimization problem and an iterative nonlinear
matching pursuit method was proposed to solve this nonlinear optimization
problem. In this paper, we prove the convergence of this nonlinear matching
pursuit method under some sparsity assumption on the signal. We consider both
well-resolved and sparse sampled signals. In the case without noise, we prove
that our method gives exact recovery of the original signal.


title: Approach to artinian algebras via natural quivers

abstract:
  Given an Artinian algebra $A$ over a field $k$, there are several
combinatorial objects associated to $A$. They are the diagram $D_A$ as defined
in [DK], the natural quiver $\Delta_A$ defined in \cite{Li} (cf. Section 2),
and a generalized version of $k$-species $(A/r, r/r^2)$ with $r$ being the
Jacobson radical of $A$. When $A$ is splitting over the field $k$, the diagram
$D_A$ and the well-known ext-quiver $\Gamma_A$ are the same. The main objective
of this paper is to investigate the relations among these combinatorial objects
and in turn to use these relations to give a characterization of the algebra
$A$.


title: Quantile Models with Endogeneity

abstract:
  In this article, we review quantile models with endogeneity. We focus on
models that achieve identification through the use of instrumental variables
and discuss conditions under which partial and point identification are
obtained. We discuss key conditions, which include monotonicity and
full-rank-type conditions, in detail. In providing this review, we update the
identification results of Chernozhukov and Hansen (2005, Econometrica). We
illustrate the modeling assumptions through economically motivated examples. We
also briefly review the literature on estimation and inference.
  Key Words: identification, treatment effects, structural models, instrumental
variables


title: Constructive aspects of Riemann's permutation theorem for series

abstract:
  The notions of permutable and weak-permutable convergence of a series
$\sum_{n=1}^{\infty}a_{n}$ of real numbers are introduced. Classically, these
two notions are equivalent, and, by Riemann's two main theorems on the
convergence of series, a convergent series is permutably convergent if and only
if it is absolutely convergent. Working within Bishop-style constructive
mathematics, we prove that Ishihara's principle \BDN implies that every
permutably convergent series is absolutely convergent. Since there are models
of constructive mathematics in which the Riemann permutation theorem for series
holds but \BDN does not, the best we can hope for as a partial converse to our
first theorem is that the absolute convergence of series with a permutability
property classically equivalent to that of Riemann implies \BDN. We show that
this is the case when the property is weak-permutable convergence.


title:
Wall-vortex composite solitons in two-component Bose-Einstein
  condensates

abstract:
  We study composite solitons, consisting of domain walls and vortex lines
attaching to the walls in two-component Bose-Einstein condensates. When the
total density of two components is homogeneous, the system can be mapped to the
O(3) nonlinear sigma model for the pseudospin representing the two-component
order parameter and the analytical solutions of the composite solitons can be
obtained. Based on the analytical solutions, we discuss the detailed structure
of the composite solitons in two-component condensates by employing the
generalized nonlinear sigma model, where all degrees of freedom of the original
Gross-Pitaevskii theory are active. The density inhomogeneity results in
reduction of the domain wall tension from that in the sigma model limit. We
find that the domain wall pulled by a vortex is logarithmically bent as a
membrane pulled by a pin, and it bends more flexibly than not only the domain
wall in the sigma model but also the expectation from the reduced tension.
Finally, we study the composite soliton structure for actual experimental
situations with trapped immiscible condensates under rotation through numerical
simulations of the coupled Gross-Pitaevskii equations.


title:
Non-Hermitian $\cal PT$-symmetric quantum mechanics of relativistic
  particles with the restriction of mass

abstract:
  The modified Dirac equations for the massive particles with the replacement
of the physical mass $m$ with the help of the relation $m\rightarrow m_1+
\gamma_5 m_2$ are investigated. It is shown that for a fermion theory with a
$\gamma_5$-mass term, the limiting of the mass specter by the value $ m_{max}=
{m_1}^2/2m_2$ takes place. In this case the different regions of the unbroken
$\cal PT$ symmetry may be expressed by means of the restriction of the physical
mass $m\leq m_{max}$. It should be noted that in the approach which was
developed by C.Bender et al. for the $\cal PT$-symmetric version of the massive
Thirring model with $\gamma_5$-mass term, the region of the unbroken $\cal
PT$-symmetry was found in the form $m_1\geq m_2$ \cite{ft12}. However on the
basis of the mass limitation $m\leq m_{max}$ we obtain that the domain $m_1\geq
m_2$ consists of two different parametric sectors: i) $0\leq m_2 \leq
m_1/\sqrt{2}$ -this values of mass parameters $m_1,m_2$ correspond to the
traditional particles for which in the limit $m_{max}\rightarrow \infty$ the
modified models are converting to the ordinary Dirac theory with the physical
mass $m$; ii)$m_1/\sqrt{2}\leq m_2 \leq m_1$ - this is the case of the unusual
particles for which equations of motion does not have a limit, when
$m_{max}\rightarrow \infty$. The presence of this possibility lets hope for
that in Nature indeed there are some "exotic fermion fields".
  As a matter of fact the formulated criterions may be used as a major test in
the process of the division of considered models into ordinary and exotic
fermion theories. It is tempting to think that the quanta of the exotic fermion
field have a relation to the structure of the "dark matter".


title: Wireless Broadcast with Physical-Layer Network Coding

abstract:
  This work investigates the maximum broadcast throughput and its achievability
in multi-hop wireless networks with half-duplex node constraint. We allow the
use of physical-layer network coding (PNC). Although the use of PNC for unicast
has been extensively studied, there has been little prior work on PNC for
broadcast. Our specific results are as follows: 1) For single-source broadcast,
the theoretical throughput upper bound is n/(n+1), where n is the "min
vertex-cut" size of the network. 2) In general, the throughput upper bound is
not always achievable. 3) For grid and many other networks, the throughput
upper bound n/(n+1) is achievable. Our work can be considered as an attempt to
understand the relationship between max-flow and min-cut in half-duplex
broadcast networks with cycles (there has been prior work on networks with
cycles, but not half-duplex broadcast networks).


title:
Phenomenological Aspects of R-parity Violating Supersymmetry with A
  Vector-like Extra Generation

abstract:
  Phenomenological analysis to the R-parity violating supersymmetry with a
vector-like extra generation is performed in detail. It is found that, via the
trilinear couplings, the correct neutrino spectrum can be obtained. The Higgs
mass rises to 125 GeV by new up-type Yukawa couplings of vector-like quarks
with no need of very heavy superpartners. Phenomena of new heavy fermions at
LHC are predicted.


title: Phenomenology of S_4 Flavor Symmetric extra U(1) model

abstract:
  We study several phenomenologies of an E_6 inspired extra U(1) model with S_4
flavor symmetry. With the assignment of left-handed quarks and leptons to
S_4-doublet, SUSY flavor problem is softened. As the extra Higgs bosons are
neutrinophilic, baryon number asymmetry in the universe is realized by
leptogenesis without causing gravitino overproduction. We find that the allowed
region for the lightest chargino mass is given by 100-140 GeV, if the dark
matter is a singlino dominated neutralino whose mass is about 36 GeV.


title: Continuous beam of laser-cooled Yb atoms

abstract:
  We demonstrate launching of laser-cooled Yb atoms in a continuous atomic
beam. The continuous cold beam has significant advantages over the more-common
pulsed fountain, which was also demonstrated by us recently. The cold beam is
formed in the following steps---(i) Atoms from a thermal beam are first Zeeman
slowed to a small final velocity, (ii) the slowed atoms are captured in a
two-dimensional magneto-optic trap (2D-MOT), and (iii) atoms are launched {\em
continuously} in the vertical direction using two sets of moving-molasses
beams, inclined at $\pm 15^\circ$ to the vertical. The cooling transition used
is the strongly-allowed ${^1S}_0 \rightarrow {^1P}_1$ transition at 399 nm. We
capture about $7 \times 10^6$ atoms in the 2D-MOT, and then launch them with a
vertical velocity of 13 m/s at a longitudinal temperature of 125(6) mK.


title:
Electronic Band Structure of Wurtzite GaP Nanowires via Resonance Raman
  Spectroscopy

abstract:
  Raman measurements are performed on defect-free wurzite GaP nanowires.
Resonance Raman measurements are carried out over the excitation energy range
between 2.19 and 2.71 eV. Resonances at 2.38 eV and 2.67 eV of the E1(LO) mode
and at 2.67 eV of the A1(LO) are observed. The presence of these intensity
resonances clearly demonstrates the existence of energy states with Gamma_9hh
and Gamma_7V (Gamma_7C) symmetries of the valence (conduction) band and allows
to measure WZ phase GaP band energies at the Gamma point. In addition, we have
investigated temperature dependent resonant Raman measurements, which allowed
us to extrapolate the zero temperature values of Gamma point energies, along
with the crystal field and spin-orbit splitting energies. Above results provide
a feedback for refining available theoretical calculations to derive the
correct wurtzite III-V semiconductor band structure.


title:
On the pulsation modes of OGLE small amplitude red giant variables in
  the LMC

abstract:
  We discuss the properties of pulsations in the OGLE Small Amplitude Red
Giants (OSARGs) in the Large Magellanic Cloud (LMC). We consider stars below
the red-giant tip in this paper. They are multi-periodic and form three
sequences in the period-luminosity plane. Comparing the periods and period
ratios with our theoretical models, we have found that these sequences
correspond to radial first to third overtones, and nonradial dipole p$_4$ and
quadrupole p$_2$ modes. The red-giant branch stars of OSARGs consist of stars
have initial masses of $\sim0.9 - 1.4M_\odot$ which corresponds to a luminosity
range of $\log L/L_\odot \simeq 2.8 - 3.4$. With these parameters, the scaled
optimal frequency $\nu_{\rm max}$ for solar-like oscillations goes through
roughly the middle of the three sequences in the period-luminosity plane,
suggesting the stochastic excitation is likely the cause of the pulsations in
OSARGs.


title:
Low-lying quasiparticle excitations in strongly-correlated
  superconductors: An ansatz from BCS quasiparticle excitations?

abstract:
  The question about the existence of Bogoliubov's quasiparticles in the BCS
wave functions underneath Gutzwiller's projection is of importance to strongly
correlated systems. We develop a method to examine the two-particle excitations
of Gutzwiller-projected BCS wave functions by using the variational Monte Carlo
approach. We find that the exact Gutzwiller-projected quasiparticle (GQP)
dispersions are quantitatively reproduced by the Gutzwiller-projected
Bogoliubov quasiparticles (GBQP) except the regions where d-wave Cooper pairing
is strong. Since GQP still shows higher energy than GBQP near the antinodes, we
believe GBQP provides a reasonable description to the low-energy excitations in
strongly correlated superconducting systems. In addition, the intimate
connection between Gutzwiller's projection and d-wave Cooper pairing may also
imply that strong correlations play a significant role in the nodal-antinodal
dichotomy seen by photoemission experiments in cuprates.


title: Internal cumulants for femtoscopy with fixed charged multiplicity

abstract:
  A detailed understanding of all effects and influences on higher-order
correlations is essential. At low charged multiplicity, the effect of a
nonpoissonian multiplicity distribution can significantly distort correlations.
Evidently, the reference samples with respect to which correlations are
measured should yield a null result in the absence of correlations. We show how
the careful specification of desired properties necessarily leads to an
average-of-multinomials reference sample. The resulting internal cumulants and
their averaging over several multiplicities fulfil all requirements of
correctly taking into account nonpoissonian multiplicity distributions as well
as yielding a null result for uncorrelated fixed-N samples. Various correction
factors are shown to be approximations at best. Careful rederivation of
statistical variances and covariances within the frequentist approach yields
errors for cumulants that differ from those used so far. We finally briefly
discuss the implementation of the analysis through a multiple event buffer
algorithm.


title: Galaxy rotation curves. The theory

abstract:
  The non-gauge vector field with as simple as possible Lagrangian
(\ref{Lagrangian}) turned out an adequate tool for macroscopic description of
the main properties of dark matter. The dependence of the velocity of a star on
the radius of the orbit $V\left(r\right) $ -- galaxy rotation curve -- is
derived analytically from the first principles\ completely within the
Einstein's general relativity. The Milgrom's empirical modification of
Newtonian dynamics in nonrelativistic limit (MOND) gets justified and specified
in detail. In particular, the transition to a plateau is accompanied by damping
oscillations. In the scale of a galaxy, and in the scale of the whole universe,
the dark matter is described by a vector field with the same energy-momentum
tensor. It is the evidence of the common physical nature. Now, when we have the
general expression (\ref{Tik b=c=0}) for the energy-momentum tensor of dark
matter, it is possible to analyze its influence on the structure and evolution
of super heavy stars and black holes.


title:
Statistics of a quantum-state-transfer Hamiltonian in the presence of
  disorder

abstract:
  We present a statistical analysis on the performance of a protocol for the
faithful transfer of a quantum state in finite qubit or spin chains, in the
presence of diagonal and off-diagonal disorder. It is shown that the
average-state fidelity, typically employed in the literature for the
quantification of the transfer, may overestimate considerably the performance
of the protocol in a single realization, leading to faulty conclusions about
the success of the transfer.


title: A new (1+1)-dimensional matrix k-constrained KP hierarchy

abstract:
  We introduce a new generalization of matrix (1+1)-dimensional k-constrained
KP hierarchy. The new hierarchy contains matrix generalizations of stationary
DS systems, (2+1)-dimensional modified Korteweg-de Vries equation and the
Nizhnik equation. A binary Darboux transformation method is proposed for
integration of systems from this hierarchy.


title: A Terradynamics of Legged Locomotion on Granular Media

abstract:
  The theories of aero- and hydrodynamics predict animal movement and device
design in air and water through the computation of lift, drag, and thrust
forces. Although models of terrestrial legged locomotion have focused on
interactions with solid ground, many animals move on substrates that flow in
response to intrusion. However, locomotor-ground interaction models on such
flowable ground are often unavailable. We developed a force model for
arbitrarily-shaped legs and bodies moving freely in granular media, and used
this "terradynamics" to predict a small legged robot's locomotion on granular
media using various leg shapes and stride frequencies. Our study reveals a
complex but generic dependence of stresses in granular media on intruder depth,
orientation, and movement direction and gives insight into the effects of leg
morphology and kinematics on movement.

categories: physics.bio-ph cond-mat.soft physics.flu-dyn q-bio.QM


title:
Growth kinetics of circular liquid domains on vesicles by
  diffusion-controlled coalescence

abstract:
  Motivated by recent experiments on multi-component membranes, the growth
kinetics of domains on vesicles is theoretically studied. It is known that the
steady-state rate of coalescence cannot be obtained by taking the long-time
limit of the coalescence rate when the membrane is regarded as an infinite
two-dimensional (2D) system. The steady-state rate of coalescence is obtained
by explicitly taking into account the spherical vesicle shape. Using the
expression of the 2D diffusion coefficient obtained in the limit of small
domain size, an analytical expression for the domain growth kinetics is
obtained when the circular shape is always maintained. For large domains, the
growth kinetics is discussed by investigating the size dependence of the
coalescence rate using the expression for the diffusion coefficient of
arbitrary domain size.


title: Thermally assisted current-induced magnetization reversal in SrRuO3

abstract:
  We inject a sequence of 1 ms current pulses into uniformly magnetized
patterns of the itinerant ferromagnet SrRuO3 until a magnetization reversal is
detected. We detect the effective temperature during the pulse and find that
the cumulative pulse time required to induce magnetization reversal depends
exponentially on 1/T. In addition, we find that the cumulative pulse time also
depends exponentially on the current amplitude. These observations indicate
current-induced magnetization reversal assisted by thermal fluctuations.


title: Thunderstorm Observations by Air-Shower Radio Antenna Arrays

abstract:
  Relativistic, charged particles present in extensive air showers lead to a
coherent emission of radio pulses which are measured to identify the shower
initiating high-energy cosmic rays. Especially during thunderstorms, there are
additional strong electric fields in the atmosphere, which can lead to further
multiplication and acceleration of the charged particles and thus have
influence on the form and strength of the radio emission. For a reliable energy
reconstruction of the primary cosmic ray by means of the measured radio signal
it is very important to understand how electric fields affect the radio
emission. In addition, lightning strikes are a prominent source of broadband
radio emissions that are visible over very long distances. This, on the one
hand, causes difficulties in the detection of the much lower signal of the air
shower. On the other hand the recorded signals can be used to study features of
the lightning development. The detection of cosmic rays via the radio emission
and the influence of strong electric fields on this detection technique is
investigated with the LOPES experiment in Karlsruhe, Germany. The important
question if a lightning is initiated by the high electron density given at the
maximum of a high-energy cosmic-ray air shower is also investigated, but could
not be answered by LOPES. But, these investigations exhibit the capabilities of
EAS radio antenna arrays for lightning studies. We report about the studies of
LOPES measured radio signals of air showers taken during thunderstorms and give
a short outlook to new measurements dedicated to search for correlations of
lightning and cosmic rays.


title: On the work distribution in quasi-static processes

abstract:
  We derive a systematic, multiple time-scale perturbation expansion for the
work distribution in isothermal quasi-static Langevin processes. To first order
we find a Gaussian distribution reproducing the result of Speck and Seifert
[Phys. Rev. E 70, 066112 (2004)]. Scrutinizing the applicability of
perturbation theory we then show that, irrespective of time-scale separation,
the expansion breaks down when applied to untypical work values from the tails
of the distribution. We thus reconcile the result of Speck and Seifert with
apparently conflicting exact expressions for the asymptotics of work
distributions in special systems and with an intuitive argument building on the
central limit theorem.


title: LOPES 3D reconfiguration and first measurements

abstract:
  The Radio detection technique of high-energy cosmic rays is based on the
radio signal emitted by the charged particles in an air shower due to their
deflection in the Earth's magnetic field. The LOPES experiment at Karlsruhe
Institute of Technology, Germany with its simple dipoles made major
contributions to the revival of this technique. LOPES is working in the
frequency range from 40 to 80 MHz and was reconfigured several times to improve
and further develop the radio detection technique. In the current setup LOPES
consists of 10 tripole antennas which measure the complete electric field
vector of the radio emission from cosmic rays. LOPES is the first experiment
measuring all three vectorial components at once and thereby gaining the full
information about the electric field vector and not only a two-dimensional
projection. Such a setup including also measurements of the vertical electric
field component is expected to increase the sensitivity to inclined showers and
help to advance the understanding of the emission mechanism. We present the
reconfiguration and calibration procedure of LOPES 3D and discuss first
measurements.


title: A Derivation of Modified Newtonian Dynamics

abstract:
  Modified Newtonian Dynamics (MOND) is a possible solution for the missing
mass problem in galactic dynamics; its predictions are in good agreement with
observations in the limit of weak accelerations. However, MOND does not derive
from a physical mechanism and does not make predictions on the transitional
regime from Newtonian to modified dynamics; rather, empirical transition
functions have to be constructed from the boundary conditions and comparison to
observations. I compare the formalism of classical MOND to the scaling law
derived from a toy model of gravity based on virtual massive gravitons (the
"graviton picture") which I proposed recently. I conclude that MOND naturally
derives from the "graviton picture" at least for the case of non-relativistic,
highly symmetric dynamical systems. This suggests that - to first order - the
"graviton picture" indeed provides a valid candidate for the physical mechanism
behind MOND and gravity on galactic scales in general.


title:
Transfer operator and conformal measures for a class of maps having
  covering property

abstract:
  Let $(X,d)$ be a metric space and $X_0$ be an open and dense subset of $X$.
We develop the Walters' theory and discuss the existence of conformal measures
in terms of the Perron-Frobenius-Ruelle operator for a continuous map
$T:X_0\rightarrow X$ and the Bowen formula about Hausdorff dimension and
Poincar\'e exponent of some invariant subsests for $T$ with some expanding
property.


title: Surface electrons at plasma walls

abstract:
  In this chapter we introduce a microscopic modelling of the surplus electrons
on the plasma wall which complements the classical description of the plasma
sheath. First we introduce a model for the electron surface layer to study the
quasistationary electron distribution and the potential at an unbiased plasma
wall. Then we calculate sticking coefficients and desorption times for electron
trapping in the image states. Finally we study how surplus electrons affect
light scattering and how charge signatures offer the possibility of a novel
charge measurement for dust grains.


title: Invariant Distributions for homogeneous flows

abstract:
  We prove that every homogeneous flow on a finite-volume homogeneous manifold
has countably many independent invariant distributions unless it is conjugate
to a linear flow on a torus. We also prove that the same conclusion holds for
every affine transformation of a homogenous space which is not conjugate to a
toral translation. As a part of the proof, we have that any smooth partially
hyperbolic flow on any compact manifold has countably many distinct minimal
sets, hence countably many distinct ergodic probability measures. As a
consequence, the Katok and Greenfield-Wallach conjectures hold in all of the
above cases.


title: Enhanced Security for Cloud Storage using File Encryption

abstract:
  Cloud computing is a term coined to a network that offers incredible
processing power, a wide array of storage space and unbelievable speed of
computation. Social media channels, corporate structures and individual
consumers are all switching to the magnificent world of cloud computing. The
flip side to this coin is that with cloud storage emerges the security issues
of confidentiality, data integrity and data availability. Since the cloud is a
mere collection of tangible super computers spread across the world,
authentication and authorization for data access is more than a necessity. Our
work attempts to overcome these security threats. The proposed methodology
suggests the encryption of the files to be uploaded on the cloud. The integrity
and confidentiality of the data uploaded by the user is ensured doubly by not
only encrypting it but also providing access to the data only on successful
authentication.


title: Projective lines over Jordan systems and geometry of Hermitian matrices

abstract:
  Any set of $\sigma$-Hermitian matrices of size $n \times n$ over a field with
involution $\sigma$ gives rise to a projective line in the sense of ring
geometry and a projective space in the sense of matrix geometry. It is shown
that the two concepts are based upon the same set of points, up to some
notational differences.


title:
On the speed of constraint propagation and the time complexity of arc
  consistency testing

abstract:
  Establishing arc consistency on two relational structures is one of the most
popular heuristics for the constraint satisfaction problem. We aim at
determining the time complexity of arc consistency testing. The input
structures $G$ and $H$ can be supposed to be connected colored graphs, as the
general problem reduces to this particular case. We first observe the upper
bound $O(e(G)v(H)+v(G)e(H))$, which implies the bound $O(e(G)e(H))$ in terms of
the number of edges and the bound $O((v(G)+v(H))^3)$ in terms of the number of
vertices. We then show that both bounds are tight up to a constant factor as
long as an arc consistency algorithm is based on constraint propagation (like
any algorithm currently known).
  Our argument for the lower bounds is based on examples of slow constraint
propagation. We measure the speed of constraint propagation observed on a pair
$G,H$ by the size of a proof, in a natural combinatorial proof system, that
Spoiler wins the existential 2-pebble game on $G,H$. The proof size is bounded
from below by the game length $D(G,H)$, and a crucial ingredient of our
analysis is the existence of $G,H$ with $D(G,H)=\Omega(v(G)v(H))$. We find one
such example among old benchmark instances for the arc consistency problem and
also suggest a new, different construction.


title: Universal scaling laws of Kerr frequency combs

abstract:
  Using the known solutions of the Lugiato-Lefever equation, we derive
universal trends of Kerr frequency combs. In particular, normalized properties
of temporal cavity soliton solutions lead us to a simple analytic estimate of
the maximum attainable bandwidth for given pump-resonator parameters. The
result is validated via comparison with past experiments encompassing a diverse
range of resonator configurations and parameters.


title:
3D climate modeling of close-in land planets: Circulation patterns,
  climate moist bistability and habitability

abstract:
  The inner edge of the classical habitable zone is often defined by the
critical flux needed to trigger the runaway greenhouse instability. This 1D
notion of a critical flux, however, may not be so relevant for inhomogeneously
irradiated planets, or when the water content is limited (land planets).
  Here, based on results from our 3D global climate model, we find that the
circulation pattern can shift from super-rotation to stellar/anti stellar
circulation when the equatorial Rossby deformation radius significantly exceeds
the planetary radius. Using analytical and numerical arguments, we also
demonstrate the presence of systematic biases between mean surface temperatures
or temperature profiles predicted from either 1D or 3D simulations.
  Including a complete modeling of the water cycle, we further demonstrate that
for land planets closer than the inner edge of the classical habitable zone,
two stable climate regimes can exist. One is the classical runaway state, and
the other is a collapsed state where water is captured in permanent cold traps.
We identify this "moist" bistability as the result of a competition between the
greenhouse effect of water vapor and its condensation. We also present
synthetic spectra showing the observable signature of these two states.
  Taking the example of two prototype planets in this regime, namely Gl581c and
HD85512b, we argue that they could accumulate a significant amount of water ice
at their surface. If such a thick ice cap is present, gravity driven ice flows
and geothermal flux should come into play to produce long-lived liquid water at
the edge and/or bottom of the ice cap. Consequently, the habitability of
planets at smaller orbital distance than the inner edge of the classical
habitable zone cannot be ruled out. Transiting planets in this regime represent
promising targets for upcoming observatories like EChO and JWST.


title:
LOPES 3D - vectorial measurements of radio emission from cosmic ray
  induced air showers

abstract:
  LOPES 3D is able to measure all three components of the electric field vector
of the radio emission from air showers. This allows a better comparison with
emission models. The measurement of the vertical component increases the
sensitivity to inclined showers. By measuring all three components of the
electric field vector LOPES 3D demonstrates by how much the reconstruction
accuracy of primary cosmic ray parameters increases. Thus LOPES 3D evaluates
the usefulness of vectorial measurements for large scale applications.


title:
Quasi-Stationary Distributions for Stochastic Approximation Algorithms
  with constant step size

abstract:
  In this paper we investigate quasi-stationary distributions {\mu}_N of
stochastic approximation algorithms with constant step size which can be viewed
as random perturbations of a time-continuous dynamical system. Inspired by
ecological models these processes have a closed absorbing set corresponding to
extinction. Under some large deviation assumptions and the existence of an
interior attractor for the ODE, we show that the weak* limit points of the QSD
{\mu}_N are invariant measures for the ODE with support in the interior
attractors.


title:
On the construction of elliptic Chudnovsky-type algorithms for
  multiplication in large extensions of finite fields

abstract:
  We indicate a strategy in order to construct bilinear multiplication
algorithms of type Chudnovsky in large extensions of any finite field. In
particular, by using the symmetric version of the generalization of
Randriambololona specialized on the elliptic curves, we show that it is
possible to construct such algorithms with low bilinear complexity. More
precisely, if we only consider the Chudnovsky-type algorithms of type symmetric
elliptic, we show that the symmetric bilinear complexity of these algorithms is
in $O(n(2q)^{\log_q^*(n)})$ where $n$ corresponds to the extension degree, and
$\log_q^*(n)$ is the iterated logarithm. Moreover, we show that the
construction of such algorithms can be done in time polynomial in $n$. Finally,
applying this method we present the effective construction, step by step, of
such an algorithm of multiplication in the finite field $\F_{3^{57}}$.


title: The Finite State MAC with Cooperative Encoders and Delayed CSI

abstract:
  In this paper, we consider the finite-state multiple access channel (MAC)
with partially cooperative encoders and delayed channel state information
(CSI). Here partial cooperation refers to the communication between the
encoders via finite-capacity links. The channel states are assumed to be
governed by a Markov process. Full CSI is assumed at the receiver, while at the
transmitters, only delayed CSI is available. The capacity region of this
channel model is derived by first solving the case of the finite-state MAC with
a common message. Achievability for the latter case is established using the
notion of strategies, however, we show that optimal codes can be constructed
directly over the input alphabet. This results in a single codebook
construction that is then leveraged to apply simultaneous joint decoding.
Simultaneous decoding is crucial here because it circumvents the need to rely
on the capacity region's corner points, a task that becomes increasingly
cumbersome with the growth in the number of messages to be sent. The common
message result is then used to derive the capacity region for the case with
partially cooperating encoders. Next, we apply this general result to the
special case of the Gaussian vector MAC with diagonal channel transfer
matrices, which is suitable for modeling, e.g., orthogonal frequency division
multiplexing (OFDM)-based communication systems. The capacity region of the
Gaussian channel is presented in terms of a convex optimization problem that
can be solved efficiently using numerical tools. The region is derived by first
presenting an outer bound on the general capacity region and then suggesting a
specific input distribution that achieves this bound. Finally, numerical
results are provided that give valuable insight into the practical implications
of optimally using conferencing to maximize the transmission rates.


title: Self-similar shock wave solutions of the non-linear Maxwell equations

abstract:
  In our study we consider nonlinear, power-law field-dependent electrical
permitivity and magnetic permeability and investigate the time-dependent
Maxwell equations with the self-similar Ansatz. This is a first-order
hyperbolic PDE system which can conserve non-continuous initial conditions
describing electromagnetic shock-waves. Besides shock-waves other interesting
solutions (e.g. with localized compact support) can be found with delicate
physical properties. Such phenomena may happen in complex materials induced by
the planned powerful Extreme Light Infrastructure(ELI) laser pulses.


title: Semantic Matching of Security Policies to Support Security Experts

abstract:
  Management of security policies has become increasingly difficult given the
number of domains to manage, taken into consideration their extent and their
complexity. Security experts has to deal with a variety of frameworks and
specification languages used in different domains that may belong to any Cloud
Computing or Distributed Systems. This wealth of frameworks and languages make
the management task and the interpretation of the security policies so
difficult. Each approach provides its own conflict management method or tool,
the security expert will be forced to manage all these tools, which makes the
field maintenance and time consuming expensive. In order to hide this
complexity and to facilitate some security experts tasks and automate the
others, we propose a security policies aligning based on ontologies process;
this process enables to detect and resolve security policies conflicts and to
support security experts in managing tasks.


title: Dr. Harold Whichello: medicine and astronomy in Cheshire

abstract:
  Dr. Harold Whichello (1870-1945) was a Cheshire General Practitioner and an
enthusiastic amateur astronomer. He joined the British Astronomical Association
in 1898 and undertook observations for its Lunar, Solar and Variable Star
Sections using a 6-inch Wray refractor. He also contributed lunar occultation
predictions and comet ephemerides to its Computing Section.


title: RX J0440.9+4431: a persistent Be/X-ray binary in outburst

abstract:
  The persistent Be/X-ray binary RX J0440.9+4431 flared in 2010 and 2011 and
has been followed by various X-ray facilities Swift, RXTE, XMM-Newton, and
INTEGRAL. We studied the source timing and spectral properties as a function of
its X-ray luminosity to investigate the transition from normal to flaring
activity and the dynamical properties of the system. We have determined the
orbital period from the long-term Swift/BAT light curve, but our determinations
of the spin period are not precise enough to constrain any orbital solution.
The source spectrum can always be described by a bulk-motion Comptonization
model of black body seed photons attenuated by a moderate photoelectric
absorption. At the highest luminosity, we measured a curvature of the spectrum,
which we attribute to a significant contribution of the radiation pressure in
the accretion process. This allows us to estimate that the transition from a
bulk-motion-dominated flow to a radiatively dominated one happens at a
luminosity of ~2e36 erg/s. The luminosity dependency of the size of the black
body emission region is found to be $r_{BB} \propto L_X^{0.39\pm0.02}$. This
suggests that either matter accreting onto the neutron star hosted in RX
J0440.9+4431 penetrates through closed magnetic field lines at the border of
the compact object magnetosphere or that the structure of the neutron star
magnetic field is more complicated than a simple dipole close to the surface


title: Superoutbursts and grazing eclipses in the dwarf nova V1227 Herculis

abstract:
  We present photometry obtained during the 2012 May and September outbursts of
the frequently outbursting dwarf nova, V1227 Her. Superhumps were present in
both cases with a peak-to peak amplitude of up to 0.28 mag, showing these
events to be superoutbursts. We show for the first time that the system
undergoes small eclipses with a depth of up to 0.08 mag, lasting 11 to 14 min,
which are likely to be grazing eclipses of the accretion disc. The September
outburst was the better observed of the two and lasted at least 14 days with an
outburst amplitude of approximately 4 magnitudes. The mean superhump period was
Psh = 0.065103(20) d. Analysis of eclipse times of minimum gave an orbital
period Porb = 0.064419(26) d, although there is some ambiguity due to the
relatively short time over which the eclipses were observed. The fractional
superhump period excess, epsilon, was 0.0106(7).


title:
On the concept of (homo)morphism : a key notion in the learning of
  abstract algebra

abstract:
  This article is dedicated to the investigation of difficulties involved in
the understanding of the homomorphism concept. It doesn't restrict to
group-theory but on the contrary raises the issue of developing teaching
strategies aiming at gaining access to structuralist thinking. Emphasis is put
on epistemological analysis and its interaction with didactics in an attempt to
make Abstract Algebra more accessible.


title: Gaussian process models for periodicity detection

abstract:
  We consider the problem of detecting and quantifying the periodic component
of a function given noise-corrupted observations of a limited number of
input/output tuples. Our approach is based on Gaussian process regression which
provides a flexible non-parametric framework for modelling periodic data. We
introduce a novel decomposition of the covariance function as the sum of
periodic and aperiodic kernels. This decomposition allows for the creation of
sub-models which capture the periodic nature of the signal and its complement.
To quantify the periodicity of the signal, we derive a periodicity ratio which
reflects the uncertainty in the fitted sub-models. Although the method can be
applied to many kernels, we give a special emphasis to the Mat\'ern family,
from the expression of the reproducing kernel Hilbert space inner product to
the implementation of the associated periodic kernels in a Gaussian process
toolkit. The proposed method is illustrated by considering the detection of
periodically expressed genes in the arabidopsis genome.


title: Quantum automorphism groups and SO(3)-deformations

abstract:
  We show that any compact quantum group having the same fusion rules as the
ones of $SO(3)$ is the quantum automorphism group of a pair $(A, \varphi)$,
where $A$ is a finite dimensional $C^*$-algebra endowed with a homogeneous
faithful state. We also study the representation category of the quantum
automorphism group of $(A, \varphi)$ when $\varphi$ is not necessarily
positive, generalizing some known results, and we discuss the possibility of
classifying the cosemisimple (not necessarily compact) Hopf algebras whose
corepresentation semi-ring is isomorphic to that of $SO(3)$.


title: Pivotal estimation in high-dimensional regression via linear programming

abstract:
  We propose a new method of estimation in high-dimensional linear regression
model. It allows for very weak distributional assumptions including
heteroscedasticity, and does not require the knowledge of the variance of
random errors. The method is based on linear programming only, so that its
numerical implementation is faster than for previously known techniques using
conic programs, and it allows one to deal with higher dimensional models. We
provide upper bounds for estimation and prediction errors of the proposed
estimator showing that it achieves the same rate as in the more restrictive
situation of fixed design and i.i.d. Gaussian errors with known variance.
Following Gautier and Tsybakov (2011), we obtain the results under weaker
sensitivity assumptions than the restricted eigenvalue or assimilated
conditions.


title: Relevance As a Metric for Evaluating Machine Learning Algorithms

abstract:
  In machine learning, the choice of a learning algorithm that is suitable for
the application domain is critical. The performance metric used to compare
different algorithms must also reflect the concerns of users in the application
domain under consideration. In this work, we propose a novel probability-based
performance metric called Relevance Score for evaluating supervised learning
algorithms. We evaluate the proposed metric through empirical analysis on a
dataset gathered from an intelligent lighting pilot installation. In comparison
to the commonly used Classification Accuracy metric, the Relevance Score proves
to be more appropriate for a certain class of applications.


title:
Frequency of Sobolev dimension distortion of horizontal subgroups of
  Heisenberg groups

abstract:
  We study the behavior of Sobolev mappings defined on the Heisenberg groups
with respect to a foliation by left cosets of a horizontal homogeneous
subgroup. We quantitatively estimate, in terms of Euclidean Hausdorff
dimension, the size of the set of cosets that are mapped onto sets of high
dimension. The proof of our main result combines ideas of Gehring and Mostow
about the absolute continuity of quasiconformal mappings with Mattila's
projection and slicing machinery.


title: k.p subband structure of the LaAlO3/SrTiO3 interface

abstract:
  Heterostructures made of transition metal oxides are new tailor-made
materials which are attracting much attention. We have constructed a 6-band k.p
Hamiltonian and used it within the envelope function method to calculate the
subband structure of a variety of LaAlO3/SrTiO3 heterostructures. By use of
density functional calculations, we determine the k.p parameters describing the
conduction band edge of SrTiO3: the three effective mass parameters, L=0.6104
eV AA^2, M=9.73 eV AA^2, N=-1.616 eV AA^2, the spin orbit splitting
Delta_SO=28.5 meV and the low temperature tetragonal distortion energy
splitting Delta_T=2.1 meV. For confined systems we find strongly anisotropic
non-parabolic subbands. As an application we calculate bands, density of states
and magnetic energy levels and compare the results to Shubnikov-de Haas quantum
oscillations observed in high magnetic fields. For typical heterostructures we
find that electric field strength at the interface of F = 0.1 meV/AA for a
carrier density of 7.2 10^{12} cm^-2 results in a subband structure that is
similar to experimental results.


title: Complex hyperbolic geometry of the figure eight knot

abstract:
  We show that the figure eight knot complement admits a uniformizable
spherical CR structure, i.e. it occurs as the manifold at infinity of a complex
hyperbolic orbifold. The uniformization is unique provided we require the
peripheral subgroups to have unipotent holonomy.


title: Superfluid transport of information in turning flocks of starlings

abstract:
  Collective decision-making in biological systems requires all individuals in
the group to go through a behavioural change of state. During this transition,
the efficiency of information transport is a key factor to prevent cohesion
loss and preserve robustness. The precise mechanism by which natural groups
achieve such efficiency, though, is currently not fully understood. Here, we
present an experimental study of starling flocks performing collective turns in
the field. We find that the information to change direction propagates across
the flock linearly in time with negligible attenuation, hence keeping group
decoherence to a minimum. This result contrasts with current theories of
collective motion, which predict a slower and dissipative transport of
directional information. We propose a novel theory whose cornerstone is the
existence of a conserved spin current generated by the gauge symmetry of the
system. The theory turns out to be mathematically identical to that of
superfluid transport in liquid helium and it explains the dissipationless
propagating mode observed in turning flocks. Superfluidity also provides a
quantitative expression for the speed of propagation of the information,
according to which transport must be swifter the stronger the group's
orientational order. This prediction is verified by the data. We argue that the
link between strong order and efficient decision-making required by
superfluidity may be the adaptive drive for the high degree of behavioural
polarization observed in many living groups. The mathematical equivalence
between superfluid liquids and turning flocks is a compelling demonstration of
the far-reaching consequences of symmetry and conservation laws across
different natural systems.


title: Emission of fermions in little string theory

abstract:
  It is well-known that little string theory (LST) black holes radiate a purely
thermal spectrum of scalar particles. This theory lives in a Hagedorn phase
with a fixed Hagedorn temperature that does not depend on its mass. Therefore,
the theory keeps a thermal profile even taking into account self-gravitating
effects and the back-reaction of the metric. This has implications concerning
the information loss paradox; one would not be able to recover any information
from the LST black hole since the emission of scalar particles is totally
uncorrelated. Several studies of the emission spectrum in LST concern scalar
fields; it is our aim in this work to extend the study to the emission of
fermions in order to verify that the most relevant conclusion for the scalar
field remains valid for the fermions fields. Thus, we have calculated the
emission probability, the flux, and also the greybody factor corresponding to a
fermion field in LST background.


title: Around groups in Hilbert Geometry

abstract:
  This is survey about action of group on Hilbert geometry. It will be a
chapter of the "Handbook of Hilbert geometry" edited by G. Besson, M. Troyanov
and A. Papadopoulos.


title:
Non-autonomous Honesty theory in abstract state spaces with applications
  to linear kinetic equations

abstract:
  We provide a honesty theory of substochastic evolution families in real
abstract state space, extending to an non-autonomous setting the result
obtained for $C_0$-semigroups in our recent contribution \textit{[On perturbed
substochastic semigroups in abstract state spaces, \textit{Z. Anal. Anwend.}
\textbf{30}, 457--495, 2011]}. The link with the honesty theory of perturbed
substochastic semigroups is established. Several applications to non-autonomous
linear kinetic equations (linear Boltzmann equation and fragmentation equation)
are provided.


title:
Multi-slit interferometry and commuting functions of position and
  momentum

abstract:
  In a recent, modified double-pinhole diffraction experiment the existence of
an interference pattern was established indirectly along with a near-perfect
imaging of the double pinhole. Our theoretical analysis shows that the
experiment constitutes a preparation of a quantum state that is, to a good
approximation, a joint eigenstate of commuting functions of position and
momentum. Gaining information about the momentum distribution by means of the
particular experimental setup is thus possible with negligible impact on the
position distribution. Furthermore, we construct explicitly a class of states
simultaneously localised on periodic sets in position and momentum space, which
are therefore eigenstates of the observables being measured jointly (to a good
approximation) in multi-slit interferometry. Finally, we show that with an
appropriate change of settings the experiment demonstrates the mutual
disturbance of position and momentum measurements.


title: 2HDM with Z_2 symmetry in light of new LHC data

abstract:
  Properties of the Z_2-symmetric Two Higgs Doublet Models (2HDM) are discussed
and confronted with new LHC data for a 125 GeV Higgs particle. The particle
discovered at LHC in 2012 has properties expected for it in the Standard Model
(SM), with a possible enhancement in the two-photon channel. SM-like Higgs
scenarios can be realized in the Two Higgs Doublet Models with Z_2 (D) symmetry
within the normal Mixed Model (with scalar sector as in MSSM) and the Inert
Doublet Model (IDM), where a good Dark Matter (DM) candidate is present. Here
we discuss both of the models.


title:
Decentralized Eigenvalue Algorithms for Distributed Signal Detection in
  Cognitive Networks

abstract:
  In this paper we derive and analyze two algorithms -- referred to as
decentralized power method (DPM) and decentralized Lanczos algorithm (DLA) --
for distributed computation of one (the largest) or multiple eigenvalues of a
sample covariance matrix over a wireless network. The proposed algorithms,
based on sequential average consensus steps for computations of matrix-vector
products and inner vector products, are first shown to be equivalent to their
centralized counterparts in the case of exact distributed consensus. Then,
closed-form expressions of the error introduced by non-ideal consensus are
derived for both algorithms. The error of the DPM is shown to vanish
asymptotically under given conditions on the sequence of consensus errors.
Finally, we consider applications to spectrum sensing in cognitive radio
networks, and we show that virtually all eigenvalue-based tests proposed in the
literature can be implemented in a distributed setting using either the DPM or
the DLA. Simulation results are presented that validate the effectiveness of
the proposed algorithms in conditions of practical interest (large-scale
networks, small number of samples, and limited number of iterations).


title:
Edge states and topological properties of electrons on the bismuth on
  silicon surface with giant spin-orbit coupling

abstract:
  We derive a model of localized edge states in the finite width strip for
two-dimensional electron gas formed in the hybrid system of bismuth monolayer
deposited on the silicon interface and described by the nearly-free electron
model with giant spin-orbit splitting. The edge states have the energy
dispersion in the bulk energy gap with the Dirac-like linear dependence on the
quasimomentum and the spin polarization coupled to the direction of
propagation, demonstrating the properties of topological insulator. The
topological stability of edge states is confirmed by the calculations of the
$Z_2$ invariant taken from the structure of the Pfaffian for the time reversal
operator for the filled bulk bands in the surface Brillouin zone which is shown
to have a stable number of zeros with the variations of material parameters.
The proposed properties of the edge states may support future advances in
experimental and technological applications of this new material in
nanoelectronics and spintronics.


title:
Equilibrium and nonequilibrium many-body perturbation theory: a unified
  framework based on the Martin-Schwinger hierarchy

abstract:
  We present a unified framework for equilibrium and nonequilibrium many-body
perturbation theory. The most general nonequilibrium many-body theory valid for
general initial states is based on a time-contour originally introduced by
Konstantinov and Perel'. The various other well-known formalisms of Keldysh,
Matsubara and the zero-temperature formalism are then derived as special cases
that arise under different assumptions. We further present a single simple
proof of Wick's theorem that is at the same time valid in all these flavors of
many-body theory. It arises simply as a solution of the equations of the
Martin-Schwinger hierarchy for the noninteracting many-particle Green's
function with appropriate boundary conditions. We further discuss a generalized
Wick theorem for general initial states on the Keldysh contour and derive how
the formalisms based on the Keldysh and Konstantinov-Perel'-contours are
related for the case of general initial states.


title: Photospheric activity, rotation and magnetic interaction in LHS 6343 A

abstract:
  Context. The Kepler mission has recently discovered a brown dwarf companion
transiting one member of the M4V+M5V visual binary system LHS 6343 AB with an
orbital period of 12.71 days. Aims. The particular interest of this transiting
system lies in the synchronicity between the transits of the brown dwarf C
component and the main modulation observed in the light curve, which is assumed
to be caused by rotating starspots on the A component. We model the activity of
this star by deriving maps of the active regions that allow us to study stellar
rotation and the possible interaction with the brown dwarf companion. Methods.
An average transit profile was derived, and the photometric perturbations due
to spots occulted during transits are removed to derive more precise transit
parameters. We applied a maximum entropy spot model to fit the out-of-transit
optical modulation as observed by Kepler during an uninterrupted interval of
500 days. It assumes that stellar active regions consist of cool spots and
bright faculae whose visibility is modulated by stellar rotation. Results.
Thanks to the extended photometric time series, we refine the determination of
the transit parameters and find evidence of spots that are occulted by the
brown dwarf during its transits. The modelling of the out-of-transit light
curve of LHS 6343 A reveals several starspots rotating with a slightly longer
period than the orbital period of the brown dwarf, i.e., 13.13 +- 0.02 days. No
signature attributable to differential rotation is observed. We find evidence
of a persistent active longitude on the M dwarf preceding the sub- companion
point by 100 deg and lasting for at least 500 days. This can be relevant for
understanding how magnetic interaction works in low-mass binary and star-planet
systems.


title:
Direct Majorana quasiparticles heat capacity observation by $^3$He Dark
  Matter detector

abstract:
  The Majorana fermion: fermion that is its own antiparticle, was predicted by
Majorana in 1937. No fundamental particles are known to be Majorana fermions,
although there are speculations that the neutrino is one. Many proposed
theories assumes that the mysterious 'dark matter', which forms the greatest
part of the universe, is composed of Majorana fermions. Even Majorana does not
yet observed as a stable particle, its can be also exist as a quasiparticle in
the edge of topological isolators. Here we reports the Dark Matter bolometer
time constant deviation which is the result of additional Majorana heat
capacity.


title: A classification of small homotopy functors from spectra to spectra

abstract:
  We show that every small homotopy functor from spectra to spectra is weakly
equivalent to a filtered colimit of representable functors represented in
cofibrant spectra. Moreover, we present this classification as a Quillen
equivalence of the category of small functors from spectra to spectra equipped
with the homotopy model structure and the opposite of the pro-category of
spectra with the strict model structure.


title:
Spectral Variation of the Hard X-ray Emission from the Crab Nebula with
  the Suzaku Hard X-ray Detector

abstract:
  The Crab Nebula is one of the brightest and most stable sources in the X-ray
sky. Year-scale flux variation from the object was recently revealed in the
hard X-ray band by four satellites. This marked the first detection of
year-scale variability from pulsar wind nebulae in the hard X-ray band. The
Crab Nebula has been observed at least once a year for calibration purposes
with the Suzaku Hard X-ray Detector (HXD) since its launch in 2005. In order to
investigate possible spectral changes as well as flux variation, the archival
data of the HXD were analyzed. The flux variation reported by other instruments
was confirmed in the 25 -- 100 keV band by the HXD in a few percent level, but
flux above 100 keV did not follow the trend in variation below 100 keV. The
hardness ratios produced utilizing the PIN and GSO sensors installed in the HXD
exhibit significant scattering, thereby indicating spectral variations in the
hard X-ray. The spectral changes are quantified by spectral fitting with a
broken power-law model. The difference between the two photon indexes of the
broken power-law model in harder and softer energy bands is in the range of <
2.54. Taking into account flux variation of 6.3% and spectral variation
time-scale of a few days, multi components of the broken power-law-shaped
synchrotron emission with different cooling times are suggested.


title: The q-Analog of the Middle Levels Problem

abstract:
  The well-known middle levels problem is to find a Hammiltonian cycle in the
graph induced from the binary Hamming graph $\cH_2(2k+1)$ by the words of
weight $k$ or $k+1$. In this paper we define the $q$-analog of the middle
levels problem. Let $n=2k+1$ and let $q$ be a power of a prime number. Consider
the set of $(k+1)$-dimensional subspaces and the set of $k$-dimensional
subspaces of $\F_q^n$. Can these subspaces be ordered in a way that for any two
adjacent subspaces $X$ and $Y$, either $X \subset Y$ or $Y \subset X$? A
construction method which yields many Hamiltonian cycles for any given $q$ and
$k=2$ is presented.


title:
Effect of Electro-Osmotic Flow on Energy Conversion on Superhydrophobic
  Surfaces

abstract:
  It has been suggested that superhydrophobic surfaces, due to the presence of
a no-shear zone, can greatly enhance transport of surface charges, leading to a
considerable increase in the streaming potential. This could find potential use
in micro-energy harvesting devices. In this paper, we show using analytical and
numerical methods, that when a streaming potential is generated in such
superhydrophobic geometries, the reverse electro-osmotic flow and hence current
generated by this, is significant. A decrease in streaming potential compared
to what was earlier predicted is expected. We also show that, due to the
electro-osmotic streaming-current, a saturation in both the power extracted and
efficiency of energy conversion is achieved in such systems for large values of
the free surface charge densities. Nevertheless, under realistic conditions,
such microstructured devices with superhydrophobic surfaces have the potential
to even reach energy conversion efficiencies only achieved in nanostructured
devices so far.


title:
On the nature of the red, 2MASS selected AGN in the local Universe I: an
  optical spectroscopic study

abstract:
  We present optical spectra for a representative sample of 27 nearby (z < 0.2)
2MASS-selected AGN with red near-IR colours (J-K 2.0). The spectra were taken
with the ISIS spectrograph on the WHT with the aim of determining the nature of
the red 2MASS AGN, in particular whether they are young quasars obscured by
their natal cocoon of gas and dust. We compare our findings with those obtained
for comparison samples of PG quasars and unobscured type 1 AGN.
  The spectra show a remarkable variety, including moderately reddened type 1
objects (45%), type 1 objects that appear similar to traditional UV/optical
selected AGN (11%), narrow-line Seyfert 1 AGN (15%), type 2 AGN (22%) and
HII/composite objects (7%). The high Balmer decrements that we measure in many
of the type 1 objects are consistent with their red J-KS colours being due to
moderate levels of dust extinction (0.2 < E(B-V) < 1.2). However, we measure
only modest velocity shifts and widths for the broader [OIII]{\lambda}5007
emission line components that are similar to those measured in the comparison
samples. This suggests that the outflows in the red 2MASS objects are not
unusual compared with those of optical/UV selected AGN of similar luminosity.
In addition, the Eddington ratios for the 2MASS sample are relatively modest.
  Overall, based on their optical spectra, we find no clear evidence that the
population of red, 2MASS selected AGN at low redshifts represents young
quasars. Most plausibly, these objects are normal type 1 AGN that are
moderately obscured by material in the outer layers of the circum-nuclear tori
or in the disks of the host galaxies.


title: Characterization of kinetic coarsening in a random-field Ising model

abstract:
  We report a study of nonequilibrium relaxation in a two-dimensional random
field Ising model at a nonzero temperature. We attempt to observe the
coarsening from a different perspective with a particular focus on three
dynamical quantities that characterize the kinetic coarsening. We provide a
simple generalized scaling relation of coarsening supported by numerical
results. The excellent data collapse of the dynamical quantities justifies our
proposition. The scaling relation corroborates the recent observation that the
average linear domain size satisfies different scaling behavior in different
time regimes.


title:
The Classification of Real Singularities Using SINGULAR. Part I:
  Splitting Lemma and Simple Singularities

abstract:
  We present algorithms to classify isolated hypersurface singularities over
the real numbers according to the classification by V.I. Arnold (Arnold et al.,
1985). This first part covers the splitting lemma and the simple singularities;
a second and a third part will be devoted to the unimodal singularities up to
corank 2. All algorithms are implemented in the SINGULAR library
realclassify.lib (Marais and Steenpass, 2012).


title: Smart Cities Software from the developer's point of view

abstract:
  The paper discusses the current state and development proposals for Smart
Cities and Future Internet projects. Definitions of a Smart City can vary but
usually tend to suggest the use of innovative Info-Communication technologies
such as the Internet of Things and Web 2.0 to deliver more effective and
efficient public services that improve living and working conditions and create
more sustainable urban environments. Our goal is to analyze the current
proposals from the developer's point of view, highlight the really new
elements, the positions borrowed from the existing tools as well as propose
some new extensions. We would like to discuss the possible extensions for the
existing proposals and describe add-ons that, by our opinion, let keep the
future research inline with the modern approaches in the web development
domain.


title: Coexistence and Survival in Conservative Lotka-Volterra Networks

abstract:
  Analyzing coexistence and survival scenarios of Lotka-Volterra (LV) networks
in which the total biomass is conserved is of vital importance for the
characterization of long-term dynamics of ecological communities. Here, we
introduce a classification scheme for coexistence scenarios in these
conservative LV models and quantify the extinction process by employing the
Pfaffian of the network's interaction matrix. We illustrate our findings on
global stability properties for general systems of four and five species and
find a generalized scaling law for the extinction time.


title: Confidence sets for persistence diagrams

abstract:
  Persistent homology is a method for probing topological properties of point
clouds and functions. The method involves tracking the birth and death of
topological features (2000) as one varies a tuning parameter. Features with
short lifetimes are informally considered to be "topological noise," and those
with a long lifetime are considered to be "topological signal." In this paper,
we bring some statistical ideas to persistent homology. In particular, we
derive confidence sets that allow us to separate topological signal from
topological noise.


title: A Zoo of Galaxies

abstract:
  We live in a universe filled with galaxies with an amazing variety of sizes
and shapes. One of the biggest challenges for astronomers working in this field
is to understand how all these types relate to each other in the background of
an expanding universe. Modern astronomical surveys (like the Sloan Digital Sky
Survey) have revolutionised this field of astronomy, by providing vast numbers
of galaxies to study. The sheer size of the these databases made traditional
visual classification of the types galaxies impossible and in 2007 inspired the
Galaxy Zoo project (www.galaxyzoo.org); starting the largest ever scientific
collaboration by asking members of the public to help classify galaxies by type
and shape. Galaxy Zoo has since shown itself, in a series of now more than 30
scientific papers, to be a fantastic database for the study of galaxy
evolution. In this Invited Discourse I spoke a little about the historical
background of our understanding of what galaxies are, of galaxy classification,
about our modern view of galaxies in the era of large surveys. I finish with
showcasing some of the contributions galaxy classifications from the Galaxy Zoo
project are making to our understanding of galaxy evolution.
  This publication has been made possible by the participation of more than
200,000 volunteers in the Galaxy Zoo project. Their contributions are
individually acknowledged at http://www.galaxyzoo.org/volunteers. KLM
acknowledges funding from the Peter and Patricia Gruber Foundation as the 2008
Peter and Patricia Gruber Foundation IAU Fellow, and from a 2010 Leverhulme
Trust Early Career Fellowship, as well as support from the Royal Astronomical
Society to attend the 28th GA of the IAU.


title:
The topological-crystalline-insulator (Pb,Sn)Te - surface states and
  their spin-polarization

abstract:
  Using a tight-binding approach we study theoretically the nature of surface
states in Pb0.4Sn0.6Te - the newly discovered
topological-crystalline-insulator. Apart from the studied before (001) surface
states, two other surface families, {011} and {111}, in which the mirror
symmetry of the crystal's rock-salt structure plays the same role in
topological protection, are considered. Our calculations show that while in
(111) surface states of (Pb,Sn)Te four single topologically protected
Dirac-cones should appear, for the (110) surface states the protection is
lifted for two L points. In this case, instead of the Dirac points energy gaps
occur in the surface states, due to the interaction between the two L valleys.
In all studied cases a chiral spin texture is obtained.


title: Pre-acceleration from Landau-Lifshitz Series

abstract:
  The Landau-Lifshitz equation is considered as an approximation of the
Abraham-Lorentz-Dirac equation. It is derived from the Abraham-Lorentz-Dirac
equation by treating radiation reaction terms as a perturbation. However, while
the Abraham-Lorentz-Dirac equation has pathological solutions of
pre-acceleration and runaway, the Landau-Lifshitz equation and its finite
higher order extensions are free of these problems. So it seems mysterious that
the property of solutions of these two equations is so different. In this paper
we show that the problems of pre-acceleration and runaway appear when one
consider a series of all-order perturbation which we call it the
Landau-Lifshitz series. We show that the Landau-Lifshitz series diverges in
general. Hence a resummation is necessary to obtain a well-defined solution
from the Landau-Lifshitz series. This resummation leads the pre-accelerating
and the runaway solutions. The analysis is focusing on the non-relativistic
case, but we can extend the results obtained here to relativistic case at least
in one dimension.

categories: hep-th math-ph math.MP physics.class-ph physics.plasm-ph


title:
Cosmological Magnetic Fields: Their Generation, Evolution and
  Observation

abstract:
  We review the possible mechanisms for the generation of cosmological magnetic
fields, discuss their evolution in an expanding Universe filled with the cosmic
plasma and provide a critical review of the literature on the subject. We put
special emphasis on the prospects for observational tests of the proposed
cosmological magnetogenesis scenarios using radio and gamma-ray astronomy and
ultra high energy cosmic rays. We argue that primordial magnetic fields are
observationally testable. They lead to magnetic fields in the intergalactic
medium with magnetic field strength and correlation length in a well defined
range. We also state the unsolved questions in this fascinating open problem of
cosmology and propose future observations to address them.


title:
On the Complexity of the Decisive Problem in Simple, Regular and
  Weighted Games

abstract:
  We study the computational complexity of an important property of simple,
regular and weighted games, which is decisiveness. We show that this concept
can naturally be represented in the context of hypergraph theory, and that
decisiveness can be decided for simple games in quasi-polynomial time, and for
regular and weighted games in polynomial time. The strongness condition poses
the main difficulties, while properness reduces the complexity of the problem,
especially if it is amplified by regularity. On the other hand, regularity also
allows to specify the problem instances much more economically, implying a
reconsideration of the corresponding complexity measure that, as we prove, has
important structural as well as algorithmic consequences.


title:
Persistence property in weighted Sobolev spaces for nonlinear dispersive
  equations

abstract:
  We generalize the Abstract Interpolation Lemma proved by the authors in [2].
Using this extension, we show in a more general context, the persistence
property for the generalized Korteweg-de Vries equation, see (1.2), in the
weighted Sobolev space with low regularity in the weight. The method used can
be applied for other nonlinear dispersive models, for instance the
multidimensional nonlinear Schrodinger equation.


title:
Potential of EBL and cosmology studies with the Cherenkov Telescope
  Array

abstract:
  Very high energy (VHE, E >100 GeV) gamma-rays are absorbed via interaction
with low-energy photons from the extragalactic background light (EBL) if the
involved photon energies are above the threshold for electron-positron pair
creation. The VHE gamma-ray absorption, which is energy dependent and increases
strongly with redshift, distorts the VHE spectra observed from distant objects.
The observed energy spectra of the AGNs carry, therefore, an imprint of the
EBL. The detection of VHE gamma-ray spectra of distant sources (z = 0.11 -
0.54) by current generation Imaging Atmospheric Cherenkov Telescopes (IACTs)
enabled to set strong upper limits on the EBL density, using certain basic
assumptions about blazar physics. In this paper it is studied how the improved
sensitivity of the Cherenkov Telescope Array (CTA) and its enlarged energy
coverage will enlarge our knowledge about the EBL and its sources. CTA will
deliver a large sample of AGN at different redshifts with detailed measured
spectra. In addition, it will provide the exciting opportunity to use gamma ray
bursts (GRBs) as probes for the EBL density at high redshifts.


title:
First measurement of the CP-violating phase in $B_s^0 \to \phi \phi$
  decays

abstract:
  A first flavour-tagged measurement of the time-dependent CP-violating
asymmetry in $B_s^0 \to \phi\phi$ decays is presented. In this decay channel,
the CP-violating weak phase arises due to CP violation in the interference
between $B_s^0$-$\bar{B}_s^0$ mixing and the $b \to s \bar{s} s $ gluonic
penguin decay amplitude. Using a sample of $pp$ collision data corresponding to
an integrated luminosity of $1.0\; fb^{-1}$ and collected at a centre-of-mass
energy of $7 \rm TeV$ with the LHCb detector, $880\ \B_s^0 \to \phi\phi$ signal
decays are obtained. The CP-violating phase is measured to be in the interval
[-2.46, -0.76] \rm rad$ at 68% confidence level. The p-value of the Standard
Model prediction is 16%.