title: A Cubic Algorithm for Computing Gaussian Volume

abstract:
  We present randomized algorithms for sampling the standard Gaussian
distribution restricted to a convex set and for estimating the Gaussian measure
of a convex set, in the general membership oracle model. The complexity of
integration is $O^*(n^3)$ while the complexity of sampling is $O^*(n^3)$ for
the first sample and $O^*(n^2)$ for every subsequent sample. These bounds
improve on the corresponding state-of-the-art by a factor of $n$. Our
improvement comes from several aspects: better isoperimetry, smoother
annealing, avoiding transformation to isotropic position and the use of the
"speedy walk" in the analysis.


title:
Homogeneous Connectivity of Potential Energy Network in a Solidlike
  State of Water Cluster

abstract:
  A novel route to the exponential trapping-time distribution within a
solidlike state in water clusters is described. We propose a simple homogeneous
network (SHN) model to investigate dynamics on the potential energy networks of
water clusters. In this model, it is shown that the trapping-time distribution
in a solidlike state follows the exponential distribution, whereas the
trapping-time distribution in local potential minima within the solidlike state
is not exponential. To confirm the exponential trapping-time distribution in a
solidlike state, we investigate water clusters, $($H${}_2$O$)_6$ and
$($H${}_2$O$)_{12}$, by molecular dynamics simulations. These clusters change
dynamically from solidlike to liquidlike state and vice versa. We find that the
probability density functions of trapping times in a solidlike state are
described by the exponential distribution whereas those of interevent times of
large fluctuations in potential energy within the solidlike state follow the
Weibull distributions. The results provide a clear evidence that transition
dynamics between solidlike and liquidlike states in water clusters are well
described by the SHN model, suggesting that the exponential trapping-time
distribution within a solidlike state originates from the homogeneous
connectivity in the potential energy network.


title:
Towards a general definition of gelation for adhesive hard-sphere
  dispersions

abstract:
  One major goal in condensed matter physics is identifying the physical
mechanisms that lead to arrested states of matter, especially gels and glasses.
The complex nature and microscopic details of each particular system are
relevant. However, from both scientific and technological viewpoints, a
general, consistent and unified definition is of paramount importance. Through
Monte Carlo computer simulations of states identified in experiments, we
demonstrate that adhesive hard-sphere dispersions are the result of rigidity
percolation with average number of bonds, $<n_b>$, equals to 2.4. This
corresponds to an established mechanism leading to phase transitions in
network-forming materials. Our findings connect the concept of critical gel
formation in colloidal suspensions with short-range attractive interactions to
the universal concept of rigidity percolation. Furthermore, the bond, angular
and local distributions along the gelation line are explicitly studied in order
to determine the topology of the structure of the critical gel state.


title: Dynamics on character varieties: a survey

abstract:
  We survey recent work on the dynamics of the outer automorphism group of a
word hyperbolic group on spaces of (conjugacy classes of) representations ofthe
group into a semi-simple Lie group G. All these results are motivated by the
fact that the mapping class group of a closed surface acts properly
discontinuously on the Teichmuller space of the surface.
  We explore two settings. 1) The work of Guichard, Labourie and Wienhard
establishing the proper discontinuity of the action of outer automorphism
groups on spaces of Anosov representations. 2) The work of Canary, Gelander,
Lee, Magid, Minsky and Storm on the case where the domain group is the
fundamental group of a compact 3-manifold with boundary and G=PSL(2,C).


title:
Criticality in Alternating Layered Ising Models: II. Exact Scaling
  Theory

abstract:
  Part I of this article studied the specific heats of planar alternating
layered Ising models with strips of strong coupling $J_1$ sandwiched between
strips of weak coupling $J_2$, to illustrate qualitatively the effects of
connectivity, proximity, and enhancement in analogy to those seen in extensive
experiments on superfluid helium by Gasparini and coworkers. It was
demonstrated graphically that finite-size scaling descriptions hold in a
variety of temperature regions including in the vicinity of the two specific
heat maxima. Here we provide exact theoretical analyses and asymptotics of the
specific heat that support and confirm the graphical findings. Specifically, at
the overall or bulk critical point, the anticipated (and always present)
logarithmic singularity is shown to vanish exponentially fast as the width of
the stronger strips increases.


title: Quasi-One-Dimensional Thermal Breakage

abstract:
  Breakage is generally understood in mechanical terms, yet nano-structures can
rupture not only under external loads but also via thermal activation. Here we
treat in a general framework the statistical mechanics of thermally induced
breakage at the nano-scale for one-dimensional systems. We test it on a simple
approximation and find that the probability of breakage controls distinct
regimes, characterized by sharp crossovers and narrow peaks in the thermal
fluctuations and specific heat. Our work provides predictions on clustering of
new phases, of relevance in nano-fabrication.


title:
Broadening the Bandwidth of Metamaterial Cloaks with Non-Foster
  Metasurfaces

abstract:
  We introduce the concept and practical design of broadband, ultrathin cloaks
based on non-Foster, negatively capacitive metasurfaces. By using properly
tailored, active frequency-selective screens conformal to an object, within the
realm of practical realization, is shown to enable drastically reduced
scattering over a wide frequency range in the microwave regime, orders of
magnitude broader than any available passive cloaking technology. The proposed
active cloak may impact not only invisibility and camouflaging, but also
practical antenna and sensing applications.


title:
Robust Decentralized Stabilization of Markovian Jump Large-Scale
  Systems: A Neighboring Mode Dependent Control Approach

abstract:
  This paper is concerned with the decentralized stabilization problem for a
class of uncertain large-scale systems with Markovian jump parameters. The
controllers use local subsystem states and neighboring mode information to
generate local control inputs. A sufficient condition involving rank
constrained linear matrix inequalities is proposed for the design of such
controllers. A numerical example is given to illustrate the developed theory.


title: A Trace Formula for Long-Range Perturbations of the Landau Hamiltonian

abstract:
  We consider the Landau Hamiltonian perturbed by a long-range electric
potential $V$. The spectrum of the perturbed operator consists of eigenvalue
clusters which accumulate to the Landau levels. First, we obtain an estimate of
the rate of the shrinking of these clusters to the Landau levels as the number
of the cluster $q$ tends to infinity. Further, we assume that there exists an
appropriate $\V$, homogeneous of order $-\rho$ with $\rho \in (0,1)$, such that
$V(x) = \V(x) + O(|x|^{-\rho - \epsilon})$, $\epsilon > 0$, as $|x| \to
\infty$, and investigate the asymptotic distribution of the eigenvalues within
a given cluster, as $q \to \infty$. We obtain an explicit description of the
asymptotic density of the eigenvalues in terms of the mean-value transform of
$\V$.


title:
Randomized incremental construction of the Hausdorff Voronoi diagram of
  non-crossing clusters

abstract:
  In the Hausdorff Voronoi diagram of a set of clusters of points in the plane,
the distance between a point t and a cluster P is the maximum Euclidean
distance between t and a point in P. This diagram has direct applications in
VLSI design. We consider so-called "non-crossing" clusters. The complexity of
the Hausdorff diagram of m such clusters is linear in the total number n of
points in the convex hulls of all clusters. We present randomized incremental
constructions for computing efficiently the diagram, improving considerably
previous results. Our best complexity algorithm runs in expected time O((n +
m(log log(n))^2)log^2(n)) and worst-case space O(n). We also provide a more
practical algorithm whose expected running time is O((n + m log(n))log^2(n))
and expected space complexity is O(n). To achieve these bounds, we augment the
randomized incremental paradigm for the construction of Voronoi diagrams with
the ability to efficiently handle non-standard characteristics of generalized
Voronoi diagrams, such as sites of non-constant complexity, sites that are not
enclosed in their Voronoi regions, and empty Voronoi regions.


title:
Liouville-type theorems for the forced Euler equations and the
  Navier-Stokes equations

abstract:
  In this paper we study the Liouville-type properties for solutions to the
steady incompressible Euler equations with forces in $\Bbb R^N$. If we assume
"single signedness condition" on the force, then we can show that a $C^1 (\Bbb
R^N)$ solution $(v,p)$ with $|v|^2+ |p|\in L^{\frac{q}{2}}(\Bbb R^N)$, $q\in
(\frac{3N}{N-1}, \infty)$ is trivial, $v=0$. For the solution of of the steady
Navier-Stokes equations, satisfying $v(x)\to 0$ as $|x|\to \infty$, the
condition $\int_{\Bbb R^3} |\Delta v|^{\frac65} dx<\infty$, which is stronger
than the important D-condition, $\int_{\Bbb R^3} |\nabla v|^2 dx <\infty$, but
both having the same scaling property, implies that $v=0$. In the appendix we
reprove the Theorem 1.1(\cite{cha0}), using the self-similar Euler equations
directly.


title: SL(2,R)-geometric phase space and (2+2)-dimensions

abstract:
  We propose an alternative geometric mathematical structure for arbitrary
phase space. The main guide in our approach is the hidden SL(2,R)-symmetry
which acts on the phase space changing coordinates by momenta and vice versa.
We show that the SL(2,R)-symmetry is implicit in any symplectic structure. We
also prove that in any sensible physical theory based on the SL(2,R)-symmetry
the signature of the flat target "spacetime" must be associated with either
one-time and one-space or at least two-time and two-space coordinates. We
discuss the consequences as well as possible applications of our approach on
different physical scenarios.


title:
Towards the fate of natural composite Higgs model through single
  $t^\prime$ search at the 8 TeV LHC

abstract:
  We analyze the observational potential of single $t'$ production in both the
$t^\prime \rightarrow bW$ and $t^\prime \rightarrow th$ decay channels at 8 TeV
LHC using an integrated luminosity of 25 $\text{fb}^{-1}$. Our analysis is
based on a simplified model with minimal coset $SO(5)/SO(4)$ in which the $t'$
is a singlet of the unbroken SO(4). The single $t'$ production, as a
consequence of electroweak symmetry breaking, is less kinematically suppressed,
associated with a light forward jet and has boosted decay products at the 8 TeV
LHC. Therefore it provides the most promising channel in searching for a heavy
$t'$. We have exploited the above kinematical features and used the jet
substructure method to reconstruct the boosted Higgs in $th$ decay channel. It
is shown that a strong constraint on the $t^\prime bW$ coupling ($g_{t^\prime
bW}/g_{tbW,SM} < 0.2 \sim 0.3$) at the 95% C. L. can be obtained for $m_{t'}
\subset (700, 1000)$ GeV.


title: Automorphism groups of smooth plane curves

abstract:
  The author determines the structure of automorphism groups of smooth plane
curves of degree at least four. Furthermore, he gives some upper bounds for the
order of automorphism groups of smooth plane curves and classifies the cases
with large automorphism groups. This paper also contains a simple proof of the
uniqueness of smooth plane curves with the full automorphism group of maximal
order for each degree.


title:
Analysis of Detached Eclipsing Binaries near the Turnoff of the Open
  Cluster NGC 7142

abstract:
  We analyze extensive BVRI photometry and radial velocity measurements for
three double-lined deeply-eclipsing binary stars in the field of the old open
cluster NGC 7142. The short period (P = 1.9096825 d) detached binary V375 Cep
is a high probability cluster member, and has a total eclipse of the secondary
star. The characteristics of the primary star (M=1.288+/-0.017 Sun) at the
cluster turnoff indicate an age of 3.6 Gyr (with a random uncertainty of 0.25
Gyr), consistent with earlier analysis of the color-magnitude diagram. The
secondary star (M = 0.871+/-0.008 Msun) is not expected to have evolved
significantly, but its radius is more than 10% larger than predicted by models.
Because this binary system has a known age, it is useful for testing the idea
that radius inflation can occur in short period binaries for stars with
significant convective envelopes due to the inhibition of energy transport by
magnetic fields. The brighter star in the binary also produces a precision
estimate of the distance modulus, independent of reddening estimates:
(m-M)_V=12.86+/-0.07.
  The other two eclipsing binary systems are not cluster members, although one
of the systems (V2) could only be conclusively ruled out as a present or former
member once the stellar characteristics were determined. That binary is within
0.5 degrees of edge-on, is in a fairly long-period eccentric binary, and
contains two almost indistiguishable stars. The other binary (V1) has a small
but nonzero eccentricity (e=0.038) in spite of having an orbital period under 5
d.


title:
Enhanced low energy fluctuations and increasing out-of-plane coherence
  in vacancy ordered NaxCoO2

abstract:
  We report Raman scattering experiments on the strongly correlated electron
system NaxCoO2 with x= 0.71 and ordered Na vacancies. In this doping regime,
NaxCoO2 exhibits a large and unusual thermopower and becomes superconducting
upon hydration. Our Raman scattering data reveal pronounced low energy
fluctuations that diverge in intensity at low temperatures. Related to these
fluctuations is a drastic decrease of an electronic scattering rate from 50 to
3 cm-1. This observation is quite different from the behavior of Na disordered
samples that have a larger and temperature independent scattering rate.
Simultaneously with the evolution of the scattering rate, phonon anomalies
point to an increasing out-of-plane coherence of the lattice with decreasing
temperature. These observations may indicate the condensation of spin polarons
into an unusual, highly dynamic ground state.


title:
Nonmonotonic Relaxation as a Result of Spatial Heterogeneity in the
  Model of In-series Blocks Chain

abstract:
  Recently the materials possessing structure of molecular and supramolecular
matrix are more and more actively studied. They are relative to many polymeric
materials of a technological origin, such as rubber, and living biological
tissues. Processes of mechanical deformation of these continuous media have
peculiarities connected, first, with accounting for internal friction and
dissipation of energy, and secondly, with nonlinearity of their elastic and
viscous properties, that is with violation of Hook and Newtons laws.
Traditional approaches to mechanics of viscoelastic bodies sometimes are
excessively difficult, and more evident and available representations are
necessary. The invaluable role in studying of the operating processes
mechanisms of elastic deformation and motility of biological materials is
played by the mathematical modeling. New effect obtained by means of computer
experiment of nonmonotonic relaxation of deformation in heterogeneous media is
considered in the present work. Rheological properties of described media are
governed by the differential equations of the first order on time (the
evolution equations), as well as a huge variety of other physical processes.
The physical phenomena in nonlinear systems with dissipation have a big
community, including such it would seem far areas, as dynamics of magnetization
in ferrite. Therefore the problem of studying new effects of viscous friction
in the conditions of nonlinearity and heterogeneity, is very actual as in
respect of fundamental research nonlinear and non-uniform environments, and in
many areas of materials science, design of new materials, engineering of
biological substitutes of living tissues and development of the micromagnetic
devices using essentially new opportunities.

categories: nlin.AO cond-mat.soft physics.bio-ph physics.comp-ph


title: PINGU Sensitivity to the Neutrino Mass Hierarchy

abstract:
  The neutrino mass hierarchy is one of the few remaining unknown parameters in
the neutrino sector and hence a primary focus of the experimental community.
The Precision IceCube Next Generation Upgrade (PINGU) experiment, to be
co-located with the IceCube DeepCore detector in the deep Antarctic glacier, is
being designed to provide a first definitive measurement of the mass hierarchy.
We have conducted feasibility studies for the detector design that demonstrate
a statistically-limited sensitivity to the hierarchy of 2.1 sigma to 3.4 sigma
per year is possible, depending on the detector geometry (20 to 40 strings) and
analysis efficiencies. First studies of the effects of systematic and
theoretical uncertainties show limited impact on the overall sensitivity to the
hierarchy. Assuming deployment of the first array elements in the 2016/17
austral summer season a 3 sigma measurement of the hierarchy is anticipated
with PINGU in 2020.


title:
Efficient spin injection through a crystalline AlOx tunnel barrier
  prepared by the oxidation of an ultra-thin Al epitaxial layer on GaAs

abstract:
  We report that an ultra-thin, post-oxidized aluminum epilayer grown on the
AlGaAs surface works as a high-quality tunnel barrier for spin injection from a
ferromagnetic metal to a semiconductor. One of the key points of the present
oxidation method is the formation of the crystalline AlOx template layer
without oxidizing the AlGaAs region near the Al/AlGaAs interface. The oxidized
Al layer is not amorphous but show well-defined single crystalline feature
reminiscent of the spinel gamma-AlOx phase. A spin-LED consisting of an Fe
layer, a crystalline AlOx barrier layer, and an AlGaAs-InGaAs double
hetero-structure has exhibited circularly polarized electroluminescence with
circular polarization of P_{EL} = 0.145 at the remnant magnetization state of
the Fe layer, indicating the relatively high spin injection efficiency (epsilon
= 2P_{EL} / P_{Fe}) of 0.63.


title: Sums of products involving power sums of $\varphi(n)$ integers

abstract:
  A sequence of rational numbers as a generalization of the sequence of
Bernoulli numbers is introduced. Sums of products involving the terms of this
generalized sequence are then obtained using an application of the Fa\`a di
Bruno's formula. These sums of products are analogous to the higher order
Bernoulli numbers and are used to develop the closed form expressions for the
sums of products involving the power sums $\displaystyle
\Psi_k(x,n):=\sum_{d|n}\mu(d)d^k S_k(\frac{x}{d}), n\in\mathbb{Z}^+$ which are
defined via the M\"obius function $\mu$ and the usual power sum $S_k(x)$ of a
real or complex variable $x.$ The power sum $S_k(x)$ is expressible in terms of
the well known Bernoulli polynomials by $\displaystyle
S_k(x):=\frac{B_{k+1}(x+1)-B_{k+1}(0)}{k+1}.$


title: De Beaux Groupes

abstract:
  In this short paper, we will provide a characterisation of interpretable
groups in a beautiful pair (K, E) of algebraically closed fields : every
interpretable group is, up to isogeny, the extension of the subgroup of
E-rational points of an algebraic group by an interpretable group which is the
quotient of an algebraic group by the E-rational points of an algebraic
subgroup.---Dans une belle paire (K;E) de corps alg\'ebriquement clos, un
groupe d\'efinissable se projette, \`a isog\'enie pr\`es, sur les points
E-rationnels d'un groupe alg\'ebrique ayant pour noyau un groupe alg\'ebrique.
Un groupe interpr\'etable est, \`a isog\'enie pr\`es, l'extension des points
E-rationnels d'un groupe alg\'ebrique par un groupe interpr\'etable, qui est
lui le quotient d'un groupe alg\'ebrique par les points E-rationnels d'un
sous-groupe alg\'ebrique.


title:
Practical Secrecy: Bridging the Gap between Cryptography and Physical
  Layer Security

abstract:
  Current security techniques can be implemented either by requiring a secret
key exchange or depending on assumptions about the communication channels. In
this paper, we show that, by using a physical layer technique known as
artificial noise, it is feasible to protect secret data without any form of
secret key exchange and any restriction on the communication channels.
Specifically, we analyze how the artificial noise can achieve practical
secrecy. By treating the artificial noise as an unshared one-time pad secret
key, we show that the proposed scheme also achieves Shannon's perfect secrecy.
Moreover, we show that achieving perfect secrecy is much easier than ensuring
non-zero secrecy capacity, especially when the eavesdropper has more antennas
than the transmitter. Focusing on the practical applications, we show that
practical secrecy and strong secrecy can be guaranteed even if the eavesdropper
attempts to remove the artificial noise. We finally show the connections
between traditional cryptography and physical layer security.


title:
Simultaneous global exact controllability of an arbitrary number of 1D
  bilinear Schr\"odinger equations

abstract:
  We consider a system of an arbitrary number of \textsc{1d} linear
Schr\"odinger equations on a bounded interval with bilinear control. We prove
global exact controllability in large time of these $N$ equations with a single
control. This result is valid for an arbitrary potential with generic
assumptions on the dipole moment of the considered particle. Thus, even in the
case of a single particle, this result extends the available literature. The
proof combines local exact controllability around finite sums of eigenstates,
proved with Coron's return method, a global approximate controllability
property, proved with Lyapunov strategy, and a compactness argument.


title:
Model theoretic stability and definability of types, after A.
  Grothendieck

abstract:
  We point out how the "Fundamental Theorem of Stability Theory", namely the
equivalence between the "non order property" and definability of types, proved
by Shelah in the 1970s, is in fact an immediate consequence of Grothendieck's
"Crit{\`e}res de compacit{\'e}" from 1952. The familiar forms for the defining
formulae then follow using Mazur's Lemma regarding weak convergence in Banach
spaces.


title: Some Aspects of Tachyon Field Cosmology

abstract:
  We study inflation, perturbations, non-gaussinity and late-time cosmological
dynamics of a tachyon field both minimally and non-minimally coupled to
gravity. By analyzing the parameters space of the model, the viability of the
model in confrontation with recent observational data is considered. In a
dynamical system technique, we study the phase space dynamics of both minimally
and non-minimally coupled tachyon field. We find the fixed points (lines in our
setup) and explore their stability. Also, we perform a statefinder diagnostic
to both cases and show that the trajectories of the state finder pairs reach a
stable state which is corresponding to a $\Lambda$CDM scenario.


title:
Hamiltonian treatment of linear field theories in the presence of
  boundaries: a geometric approach

abstract:
  The purpose of this paper is to study in detail the constraint structure of
the Hamiltonian and symplectic-Lagrangian descriptions for the scalar and
electromagnetic fields in the presence of spatial boundaries. We carefully
discuss the implementation of the geometric constraint algorithm of Gotay,
Nester and Hinds with special emphasis on the relevant functional analytic
aspects of the problem. This is an important step towards the rigorous
understanding of general field theories in the presence of boundaries, very
especially when these fail to be regular. The geometric approach developed in
the paper is also useful with regard to the interpretation of the physical
degrees of freedom and the nature of the constraints when both gauge symmetries
and boundaries are present.


title: Equilibrium in Labor Markets with Few Firms

abstract:
  We study competition between firms in labor markets, following a
combinatorial model suggested by Kelso and Crawford [1982]. In this model, each
firm is trying to recruit workers by offering a higher salary than its
competitors, and its production function defines the utility generated from any
actual set of recruited workers. We define two natural classes of production
functions for firms, where the first one is based on additive capacities
(weights), and the second on the influence of workers in a social network. We
then analyze the existence of pure subgame perfect equilibrium (PSPE) in the
labor market and its properties. While neither class holds the gross
substitutes condition, we show that in both classes the existence of PSPE is
guaranteed under certain restrictions, and in particular when there are only
two competing firms. As a corollary, there exists a Walrasian equilibrium in a
corresponding combinatorial auction, where bidders' valuation functions belong
to these classes.
  While a PSPE may not exist when there are more than two firms, we perform an
empirical study of equilibrium outcomes for the case of weight-based games with
three firms, which extend our analytical results. We then show that stability
can in some cases be extended to coalitional stability, and study the
distribution of profit between firms and their workers in weight-based games.


title:
Raman spectroscopy as a versatile tool for studying the properties of
  graphene

abstract:
  Raman spectroscopy is an integral part of graphene research. It is used to
determine the number and orientation of layers, the quality and types of edge,
and the effects of perturbations, such as electric and magnetic fields, strain,
doping, disorder and functional groups. This, in turn, provides insight into
all $sp^2$-bonded carbon allotropes, because graphene is their fundamental
building block. Here we review the state of the art, future directions and open
questions in Raman spectroscopy of graphene. We describe essential physical
processes whose importance has only recently been recognized, such as the
various types of resonance at play, and the role of quantum interference. We
update all basic concepts and notations, and propose a terminology that is able
to describe any result in literature. We finally highlight the potential of
Raman spectroscopy for layered materials other than graphene.


title:
Well-posedness and longtime behavior for the modified phase-field
  crystal equation

abstract:
  We consider a modification of the so-called phase-field crystal (PFC)
equation introduced by K.R. Elder et al. This variant has recently been
proposed by P. Stefanovic et al. to distinguish between elastic relaxation and
diffusion time scales. It consists of adding an inertial term (i.e. a
second-order time derivative) into the PFC equation. The mathematical analysis
of the resulting equation is more challenging with respect to the PFC equation,
even at the well-posedness level. Moreover, its solutions do not regularize in
finite time as in the case of PFC equation. Here we analyze the modified PFC
(MPFC) equation endowed with periodic boundary conditions. We first prove the
existence and uniqueness of a solution with initial data in a bounded energy
space. This solution satisfies some uniform dissipative estimates which allow
us to study the global longtime behavior of the corresponding dynamical system.
In particular, we establish the existence of an exponential attractor. Then we
demonstrate that any trajectory originating from the bounded energy phase space
does converge to a unique equilibrium. This is done by means of a suitable
version of the {\L}ojasiewicz-Simon inequality. A convergence rate estimate is
also given.


title: Distributed Heuristic Forward Search for Multi-Agent Systems

abstract:
  This paper describes a number of distributed forward search algorithms for
solving multi-agent planning problems. We introduce a distributed formulation
of non-optimal forward search, as well as an optimal version, MAD-A*. Our
algorithms exploit the structure of multi-agent problems to not only distribute
the work efficiently among different agents, but also to remove symmetries and
reduce the overall workload. The algorithms ensure that private information is
not shared among agents, yet computation is still efficient -- outperforming
current state-of-the-art distributed planners, and in some cases even
centralized search -- despite the fact that each agent has access only to
partial information.


title: Assouad dimension, Nagata dimension, and uniformly close metric tangents

abstract:
  We study the Assouad dimension and the Nagata dimension of metric spaces. As
a general result, we prove that the Nagata dimension of a metric space is
always bounded from above by the Assouad dimension. Most of the paper is
devoted to the study of when these metric dimensions of a metric space are
locally given by the dimensions of its metric tangents. Having uniformly close
tangents is not sufficient. What is needed in addition is either that the
tangents have dimension with uniform constants independent from the point and
the tangent, or that the tangents are unique. We will apply our results to
equiregular subRiemannian manifolds and show that locally their Nagata
dimension equals the topological dimension.


title: Supersparse Linear Integer Models for Predictive Scoring Systems

abstract:
  We introduce Supersparse Linear Integer Models (SLIM) as a tool to create
scoring systems for binary classification. We derive theoretical bounds on the
true risk of SLIM scoring systems, and present experimental results to show
that SLIM scoring systems are accurate, sparse, and interpretable
classification models.


title:
On pseudo-invereses of matrices and their characteristic polynomials in
  supertropical algebra

abstract:
  The only invertible matrices in tropical algebra are diagonal matrices,
permutation matrices and their products. However, the pseudo-inverse
$A^\nabla$, defined as $\frac{adj(A)}{det(A)}$, with $det(A)$ being the
tropical permanent (also called the tropical determinant) of a matrix $A$,
inherits some classical algebraic properties and has some surprising new ones.
Defining $B$ and $B'$ to be tropically similar if $B' =A^\nabla BA$, we examine
the characteristic (max-)polynomials of tropically similar matrices as well as
those of pseudo-inverses. Other miscellaneous results include a new proof of
the identity for $det(AB)$ and a connection to stabilization of the powers of
definite matrices.


title:
Constraints on the fundamental topological parameters of spatial
  tessellations

abstract:
  Tessellations of $R^3$ that use convex polyhedral cells to fill the space can
be extremely complicated, especially if they are not facet-to-facet, that is,
if the facets of a cell do not necessarily coincide with the facets of that
cell's neighbours. In a recent paper (Weiss and Cowan, Adv.Appl.Prob. 2011), we
have developed a theory which covers these complicated cases, at least with
respect to their combinatorial topology. The theory required seven parameters,
three of which suffice for facet-to-facet cases; the remaining four parameters
are needed for the awkward adjacency concepts that arise in the general case.
This current paper establishes constraints that apply to these seven parameters
and so defines a permissible region within their seven-dimensional space, a
region which we discover is not bounded. Our constraints in the relatively
simple facet-to-facet case are also new.


title:
Quantum oblivious transfer and bit commitment protocols based on two
  non-orthogonal states coding

abstract:
  Oblivious transfer protocols (R-OT and OT$_{1}^{2}$) are presented based on
non-orthogonal states transmission, and the bit commitment protocols on the top
of OT$_{1}^{2}$ are constructed. Although these OT protocols are all
unconditional secure, the bit commitment protocols based on OT protocols are
not secure against attack similar to that presented by no-go theorem.


title: Shape transitions in soft spheres regulated by elasticity

abstract:
  We study elasticity-driven morphological transitions of soft spherical core
shell structures in which the core can be treated as an isotropic elastic
continuum and the surface or shell as a tensionless liquid layer, whose elastic
response is dominated by bending. To generate the transitions, we consider the
case where the surface area of the liquid layer is increased for a fixed amount
of interior elastic material. We find that generically there is a critical
excess surface area at which the isotropic sphere becomes unstable to buckling.
At this point it adopts a lower symmetry wrinkled structure that can be
described by a spherical harmonic deformation. We study the dependence of the
buckled sphere and critical excess area of the transition on the elastic
parameters and size of the system. We also relate our results to recent
experiments on the wrinkling of gel-filled vesicles as their interior volume is
reduced. The theory may have broader applications to a variety of related
structures from the macroscopic to the microscopic, including the wrinkling of
dried peas, raisins, as well as the cell nucleus.


title: Hints of an axion-like particle mixing in the GeV gamma-ray blazar data?

abstract:
  Axion-Like Particles (ALPs), if exist in nature, are expected to mix with
photons in the presence of an external magnetic field. The energy range of
photons which undergo strong mixing with ALPs depends on the ALP mass, on its
coupling with photons as well as on the external magnetic field and particle
density configurations. Recent observations of blazars by the Fermi Gamma-Ray
Space Telescope in the 0.1-300 GeV energy range show a break in their spectra
in the 1-10 GeV range. We have modeled this spectral feature for the
flat-spectrum radio quasar 3C454.3 during its November 2010 outburst, assuming
that a significant fraction of the gamma rays convert to ALPs in the large
scale jet of this blazar. Using theoretically motivated models for the magnetic
field and particle density configurations in the kiloparsec scale jet, outside
the broad-line region, we find an ALP mass $m_a\sim (1-3)\cdot 10^{-7}$ eV and
coupling $g_{a\gamma} \sim (1-3)\cdot 10^{-10}$ GeV$^{-1}$ after performing an
illustrative statistical analysis of spectral data in four different epochs of
emission. The precise values of $m_a$ and $g_{a\gamma}$ depend weakly on the
assumed particle density configuration and are consistent with the current
experimental bounds on these quantities. We apply this method and ALP
parameters found from fitting 3C454.3 data to another flat-spectrum radio
quasar PKS1222+216 (4C+21.35) data up to 400 GeV, as a consistency check, and
found good fit. We find that the ALP-photon mixing effect on the GeV spectra
may not be washed out for any reasonable estimate of the magnetic field in the
intergalactic media.


title: Estimates for the asymptotic convergence factor of two intervals

abstract:
  Let $E$ be the union of two real intervals not containing zero. Then
$L_n^r(E)$ denotes the supremum norm of that polynomial $P_n$ of degree less
than or equal to $n$, which is minimal with respect to the supremum norm
provided that $P_n(0)=1$. It is well known that the limit
$\kappa(E):=\lim_{n\to\infty}\sqrt[n]{L_n^r(E)}$ exists, where $\kappa(E)$ is
called the asymptotic convergence factor, since it plays a crucial role for
certain iterative methods solving large-scale matrix problems. The factor
$\kappa(E)$ can be expressed with the help of Jacobi's elliptic and theta
functions, where this representation is very involved. In this paper, we give
precise upper and lower bounds for $\kappa(E)$ in terms of elementary functions
of the endpoints of $E$.


title: Tilting bundles on orders on $P^d$

abstract:
  We introduce a class of orders on $P^d$ called Geigle-Lenzing orders and show
that they have tilting bundles. Moreover we show that their module categories
are equivalent to the categories of coherent sheaves on Geigle-Lenzing spaces
introduced in Herschend, Iyama, Minamoto and Oppermann.


title: A lower bound for the norm of the minimal residual polynomial

abstract:
  Let $S$ be a compact infinite set in the complex plane with $0\notin{S}$, and
let $R_n$ be the minimal residual polynomial on $S$, i.e., the minimal
polynomial of degree at most $n$ on $S$ with respect to the supremum norm
provided that $R_n(0)=1$. For the norm $L_n(S)$ of the minimal residual
polynomial, the limit $\kappa(S):=\lim_{n\to\infty}\sqrt[n]{L_n(S)}$ exists. In
addition to the well-known and widely referenced inequality
$L_n(S)\geq\kappa(S)^n$, we derive the sharper inequality
$L_n(S)\geq2\kappa(S)^n/(1+\kappa(S)^{2n})$ in the case that $S$ is the union
of a finite number of real intervals. As a consequence, we obtain a slight
refinement of the Bernstein--Walsh Lemma.


title: Symmetry Classification of quasi-linear PDE's. II: an exceptional case

abstract:
  This short note completes the symmetry analysis of a class of quasi-linear
partial differential equations considered in the previous paper (Nonlinear
Dynamics, Vol. 51, 309-316 (2008)): it deals with the presence of an
"exceptional" Lie point symmetry, not previously examined, which is admitted
only if the involved parameters are fixed by precise relationships. The
peculiarity of this symmetry is enhanced by the fact that it leads to a
solution relevant in the theory of plasma physics, and also related to the
presence of a nontrivial example of a conditional symmetry of weak type.


title: Cis-Trans Dynamical Asymmetry in Driven Polymer Translocation

abstract:
  During polymer translocation driven by e.g. voltage drop across a nanopore,
the segments in the cis-side is incessantly pulled into the pore, which are
then pushed out of it into the trans-side. This pulling and pushing polymer
segments are described in the continuum level by nonlinear transport processes
known, respectively, as fast and slow diffusions. By matching solutions of both
sides through the mass conservation across the pore, we provide a physical
basis for the cis and trans dynamical asymmetry, a feature repeatedly reported
in recent numerical simulations. We then predict how the total driving force is
dynamically allocated between cis (pulling) and trans (pushing) sides,
demonstrating that the trans-side event adds a finite-chain length effect to
the dynamical scaling, which may become substantial for weak force and/or high
pore friction cases.


title:
Star formation with disc accretion and rotation I. Stars between 2 and
  22 Msol at solar metallicity

abstract:
  The way angular momentum is built up in stars during their formation process
may have an impact on their further evolution. In the frame of the cold disc
accretion scenario, we study for the first time how angular momentum builds up
inside the star during its formation and what are the consequences for its
evolution on the main sequence (MS). Computation begins from a hydrostatic core
on the Hayashi line of 0.7 Msol at solar metallicity (Z=0.014) rotating as a
solid body. Accretion rates depending on the luminosity of the accreting object
are considered varying between 1.5e-5 and 1.7e-3 Msol/yr. The accreted matter
is assumed to have an angular velocity equal to that of the outer layer of the
accreting star. Models are computed for a mass-range on the zero-age main
sequence (ZAMS) between 2 and 22 Msol. We study how the internal and surface
velocities vary as a function of time during the accretion phase and the
evolution towards the ZAMS. Stellar models, whose evolution has been followed
along the pre-MS phase, are found to exhibit a shallow gradient of angular
velocity on the ZAMS. Interestingly, for masses on the ZAMS larger than 8 Msol,
there exists a maximum surface velocity that can be reached through the present
scenario of formation. Typically, for 14 Msol models, only stars with surface
velocities on the ZAMS lower than about 45% of the critical velocity can be
formed. To reach higher velocities would require to start from cores rotating
above the critical limit. We find that this upper velocity limit is smaller for
higher masses. In contrast, below 8 Msol, there is no restriction and the whole
domain of velocities, up to the critical one, can be reached.


title: Geometric properties of inverse polynomial images

abstract:
  Given a polynomial $\T_n$ of degree $n$, consider the inverse image of $\R$
and $[-1,1]$, denoted by $\T_n^{-1}(\R)$ and $\T_n^{-1}([-1,1])$, respectively.
It is well known that $\T_n^{-1}(\R)$ consists of $n$ analytic Jordan arcs
moving from $\infty$ to $\infty$. In this paper, we give a necessary and
sufficient condition such that (1) $\T_n^{-1}([-1,1])$ consists of $\nu$
analytic Jordan arcs and (2) $\T_n^{-1}([-1,1])$ is connected, respectively.


title: Inequalities for the Jacobian elliptic functions with complex modulus

abstract:
  Despite the fact that there is a huge amount on papers and books devoted to
the theory of Jacobian elliptic functions, very little is known when the
modulus $k$ of these functions lies outside the unit interval $[0,1]$. In this
note, we prove some simple inequalities for the absolute value of Jacobian
elliptic functions with complex modulus.


title: Some properties of the one-dimensional L\'{e}vy crystal

abstract:
  We introduce and discuss the one-dimensional L\'{e}vy crystal as a probable
candidate for an experimentally accessible realization of space fractional
quantum mechanics (SFQM) in a condensed matter environment. The discretization
of the space fractional Schr\"{o}dinger equation with the help of shifted
Gr\"{u}nwald-Letnikov derivatives delivers a straight-forward route to define
the L\'{e}vy crystal of order $\alpha \in (1,2]$. As key ingredients for its
experimental identification we study the dispersion relation as well as the
density of states for arbitrary $\alpha \in (1,2]$. It is demonstrated that in
the limit of small wavenumbers all interesting properties of continuous space
SFQM are recovered, while for $\alpha \to 2$ the well-established nearest
neighbor one-dimensional tight binding chain arises.


title: A density result concerning inverse polynomial images

abstract:
  In this paper, we consider polynomials of degree $n$, for which the inverse
image of $[-1,1]$ consists of two Jordan arcs. We prove that the four endpoints
of these arcs form an ${\cal O}(1/n)$-net in the complex plane.


title: Electromechanical Piezoresistive Sensing in Suspended Graphene Membranes

abstract:
  Monolayer graphene exhibits exceptional electronic and mechanical properties,
making it a very promising material for nanoelectromechanical (NEMS) devices.
Here, we conclusively demonstrate the piezoresistive effect in graphene in a
nano-electromechanical membrane configuration that provides direct electrical
readout of pressure to strain transduction. This makes it highly relevant for
an important class of nano-electromechanical system (NEMS) transducers. This
demonstration is consistent with our simulations and previously reported gauge
factors and simulation values. The membrane in our experiment acts as a strain
gauge independent of crystallographic orientation and allows for aggressive
size scalability. When compared with conventional pressure sensors, the sensors
have orders of magnitude higher sensitivity per unit area.


title: Growth or Reproduction: Emergence of an Evolutionary Optimal Strategy

abstract:
  Modern ecology has re-emphasized the need for a quantitative understanding of
the original 'survival of the fittest theme' based on analyzis of the intricate
trade-offs between competing evolutionary strategies that characterize the
evolution of life. This is key to the understanding of species coexistence and
ecosystem diversity under the omnipresent constraint of limited resources. In
this work we propose an agent based model replicating a community of
interacting individuals, e.g. plants in a forest, where all are competing for
the same finite amount of resources and each competitor is characterized by a
specific growth-reproduction strategy. We show that such an evolution dynamics
drives the system towards a stationary state characterized by an emergent
optimal strategy, which in turn depends on the amount of available resources
the ecosystem can rely on. We find that the share of resources used by
individuals is power-law distributed with an exponent directly related to the
optimal strategy. The model can be further generalized to devise optimal
strategies in social and economical interacting systems dynamics.


title: Phenomenology of Light Fermionic Asymmetric Dark Matter

abstract:
  Asymmetric dark matter (ADM) has been an attractive possibility attempting to
explain the observed ratio of baryon to dark matter abundance in the universe.
While a bosonic ADM is constrained by the limits from existence of old neutron
stars, a fermionic ADM requires an additional light particle in order to
annihilate its symmetric component in the early universe. We revisit the
phenomenology of a minimal GeV scale fermionic ADM model including a light
scalar state. The current constraints on this scenario from cosmology, dark
matter direct detection, flavour physics and collider searches are investigated
in detail. We estimate the future reach on the model parameter space from
next-generation dark matter direct detection experiments, Higgs boson property
measurements and search for light scalars at the LHC, as well as the
determination of Higgs invisible branching ratio at the proposed ILC.


title: Stable intersection of middle-$\alpha$ Cantor sets

abstract:
  In the present paper, We introduce a pair of middle Cantor sets namely
$(C_\alpha, C_\beta)$ having stable intersection, while the product of their
thickness is smaller than one. Furthermore, the arithmetic difference
$C_\alpha- \lambda C_\beta$ contains at least one interval for each nonzero
number $\lambda$.


title: On the arithmetic difference of middle Cantor sets

abstract:
  Suppose that $\mathcal{C}$ is the space of all middle Cantor sets. We
characterize all triples $(\alpha,~\beta,~\lambda)\in
\mathcal{C}\times\mathcal{C}\times \mathbb{R}^*$ that satisfy $C_\alpha-
\lambda C_\beta=[-\lambda,~1]. $ Also all triples (that are dense in
$\mathcal{C}\times\mathcal{C}\times \mathbb{R}^*$) has been determined such
that $C_\alpha- \lambda C_\beta$ forms the attractor of an iterated function
system. Then we found a new family of the pair of middle Cantor sets
$\mathcal{P}$ in a way that for each $(C_\alpha,~ C_\beta)\in\mathcal{P}$,
there exists a dense subfield $F\subset \mathbb{R}$ such that for each $\mu \in
F$, the set $C_\alpha- \mu C_\beta$ contains an interval or has zero Lebesgue
measure. In sequel, conditions on the functions $f, ~g$ and the pair
$(C_\alpha,~C_\beta)$ is provided which $f(C_{\alpha})- g(C_{\beta})$ contains
an interval. This leads us to denote another type of stability in the
intersection of two Cantor sets. We prove the existence of this stability for
regular Cantor sets that have stable intersection and its absence for those
which the sum of their Hausdorff dimension is less than one. At the end,
special middle Cantor sets $C_\alpha$ and $C_\beta$ are introduced. Then the
iterated function system corresponding to the attractor
$C_{\alpha}-\frac{2\alpha}{\beta}C_\beta$ is characterized. Some specifications
of the attractor has been presented that keep our example as an exception.
  We also show that $\sqrt{C_{\alpha}}$ - $\sqrt{C_{\beta}}$ contains at least
one interval.


title:
Constraints on the Viscosity and Magnetic Field in Hot Accretion Flows
  around Black Holes

abstract:
  The magnitude of the viscosity and magnetic field parameters in hot accretion
flows is investigated in low luminosity active galactic nuclei (LLAGNs).
Theoretical studies show that a geometrically thin, optically thick disk is
truncated at mass accretion rates less than a critical value by mass evaporated
vertically from the disk to the corona, with the truncated region replaced by
an advection dominated accretion flow (ADAF). The critical accretion rate for
such a truncation is a function of the viscosity and magnetic field.
Observations of X-ray photon indices and spectral fits of a number of LLAGNs
published in the literature provide an estimate of the critical rate of mass
accretion and the truncation radius respectively. By comparing the
observational results with theoretical predictions, the viscosity and magnetic
field parameters in the hot accretion flow region are estimated. Specifically,
the mass accretion rates inferred in different sources constrain the viscosity
parameter, whereas the truncation radii of the disk, as inferred from spectral
fits, further constrain the magnetic field parameter. It is found that the
value of the viscosity parameter in the corona/ADAF ranges from 0.17 to 0.5,
with values clustered about 0.2-0.3. Magnetic pressure is required by the
relatively small truncation radii for some LLAGNs and is found to be as high as
its equipartition value with the gas pressure. The inferred values of the
viscosity parameter are in agreement with those obtained from the observations
of non-stationary accretion in stellar mass black hole X-ray transients. This
consistency provides support for the paradigm that a geometrically thin disk is
truncated by means of a mass evaporation process from the disk to the corona at
low mass accretion rates.


title:
Multiplicities in GGGRs for Classical Type Groups with Connected Centre
  I

abstract:
  Assume $G$ is a connected reductive algebraic group defined over
$\bar{\mathbb{F}_p}$ such that $p$ is good prime for $G$. Furthermore we assume
that $Z(G)$ is connected and $G/Z(G)$ is simple of classical type. Let $F$ be a
Frobenius endomorphism of $G$ admitting an $\mathbb{F}_q$-rational structure
$G^F$. This paper is one of a series whose overall goal is to compute
explicitly the multiplicity $< D_0745664 {G^F}(\Gamma_u),\chi>$ where: $\chi$
is an irreducible character of $G^F$, $D_{G^F}(\Gamma_u)$ is the Alvis--Curtis
dual of a generalised Gelfand--Graev representation of $G^F$ and $u \in G^F$ is
contained in the unipotent support of $\chi$. In this paper we complete the
first step towards this goal. Namely we explicitly compute, under some
restrictions on $q$, the scalars relating the characteristic functions of
character sheaves of $G$ to the almost characters of $G^F$ whenever the support
of the character sheaf contains a unipotent element. We achieve this by
adapting a method of Lusztig who answered this question when $G$ is a special
orthogonal group $\SO_{2n+1}(\mathbb{K})$. Consequently the main result of this
paper is due to Lusztig when $G = \SO_{2n+1}(\mathbb{K})$.


title: Line Spectrum Estimation with Probabilistic Priors

abstract:
  For line spectrum estimation, we derive the maximum a posteriori probability
estimator where prior knowledge of frequencies is modeled probabilistically.
Since the spectrum is periodic, an appropriate distribution is the circular von
Mises distribution that can parameterize the entire range of prior certainty of
the frequencies. An efficient alternating projections method is used to solve
the resulting optimization problem. The estimator is evaluated numerically and
compared with other estimators and the Cram\'er-Rao bound.


title: Design of an Agent for Answering Back in Smart Phones

abstract:
  The objective of the paper is to design an agent which provides efficient
response to the caller when a call goes unanswered in smartphones. The agent
provides responses through text messages, email etc stating the most likely
reason as to why the callee is unable to answer a call. Responses are composed
taking into consideration the importance of the present call and the situation
the callee is in at the moment like driving, sleeping, at work etc. The agent
makes decisons in the compostion of response messages based on the patterns it
has come across in the learning environment. Initially the user helps the agent
to compose response messages. The agent associates this message to the percept
it recieves with respect to the environment the callee is in. The user may
thereafter either choose to make to response system automatic or choose to
recieve suggestions from the agent for responses messages and confirm what is
to be sent to the caller.


title:
Alternative separation of exchange and correlation energies in
  range-separated density-functional perturbation theory

abstract:
  An alternative separation of short-range exchange and correlation energies is
used in the framework of second-order range-separated density-functional
perturbation theory. This alternative separation was initially proposed by
Toulouse et al. [Theor. Chem. Acc. 114, 305 (2005)] and relies on a long-range
interacting wavefunction instead of the non-interacting Kohn-Sham one. When
second-order corrections to the density are neglected, the energy expression
reduces to a range-separated double-hybrid (RSDH) type of functional, RSDHf,
where "f" stands for "full-range integrals" as the regular full-range
interaction appears explicitly in the energy expression when expanded in
perturbation theory. In contrast to usual RSDH functionals, RSDHf describes the
coupling between long- and short-range correlations as an orbital-dependent
contribution. Calculations on the first four noble-gas dimers show that this
coupling has a significant effect on the potential energy curves in the
equilibrium region, improving the accuracy of binding energies and equilibrium
bond distances when second-order perturbation theory is appropriate.


title: Maass waveforms and low-lying zeros

abstract:
  The Katz-Sarnak Density Conjecture states that the behavior of zeros of a
family of $L$-functions near the central point (as the conductors tend to zero)
agrees with the behavior of eigenvalues near 1 of a classical compact group (as
the matrix size tends to infinity). Using the Petersson formula, Iwaniec, Luo
and Sarnak proved that the behavior of zeros near the central point of
holomorphic cusp forms agrees with the behavior of eigenvalues of orthogonal
matrices for suitably restricted test functions $\phi$. We prove similar
results for families of cuspidal Maass forms, the other natural family of ${\rm
GL}_2/\mathbb{Q}$ $L$-functions. For suitable weight functions on the space of
Maass forms, the limiting behavior agrees with the expected orthogonal group.
We prove this for $\Supp(\widehat{\phi})\subseteq (-3/2, 3/2)$ when the level
$N$ tends to infinity through the square-free numbers; if the level is fixed
the support decreases to being contained in $(-1,1)$, though we still uniquely
specify the symmetry type by computing the 2-level density.


title:
Magnetic self-organisation in Hall-dominated magnetorotational
  turbulence

abstract:
  The magnetorotational instability (MRI) is the most promising mechanism by
which angular momentum is efficiently transported outwards in astrophysical
discs. However, its application to protoplanetary discs remains problematic.
These discs are so poorly ionised that they may not support magnetorotational
turbulence in regions referred to as `dead zones'. It has recently been
suggested that the Hall effect, a non-ideal magnetohydrodynamic (MHD) effect,
could revive these dead zones by enhancing the magnetically active column
density by an order of magnitude or more. We investigate this idea by
performing local, three-dimensional, resistive Hall-MHD simulations of the MRI
in situations where the Hall effect dominates over Ohmic dissipation. As
expected from linear stability analysis, we find an exponentially growing
instability in regimes otherwise linearly stable in resistive MHD. However,
instead of vigorous and sustained magnetorotational turbulence, we find that
the MRI saturates by producing large-scale, long-lived, axisymmetric structures
in the magnetic and velocity fields. We refer to these structures as zonal
fields and zonal flows, respectively. Their emergence causes a steep reduction
in turbulent transport by at least two orders of magnitude from extrapolations
based upon resistive MHD, a result that calls into question contemporary models
of layered accretion. We construct a rigorous mean-field theory to explain this
new behaviour and to predict when it should occur. Implications for
protoplanetary disc structure and evolution, as well as for theories of planet
formation, are briefly discussed.


title:
Extended Bernoulli and Stirling matrices and related combinatorial
  identities

abstract:
  In this paper we establish plenty of number theoretic and combinatoric
identities involving generalized Bernoulli and Stirling numbers of both kinds.
These formulas are deduced from Pascal type matrix representations of Bernoulli
and Stirling numbers. For this we define and factorize a modified Pascal matrix
corresponding to Bernoulli and Stirling cases.


title: Dynamical spin-spin coupling of quantum dots

abstract:
  We carried out a nested Schrieffer-Wolff transformation of an Anderson
two-impurity Hamiltonian to study the spin-spin coupling between two dynamical
quantum dots under the influence of rotating transverse magnetic field. As a
result of the rotating field, we predict a novel Ising type spin-spin coupling
mechanism between quantum dots, whose strength is tunable via the magnitude of
the rotating field. The strength of the new coupling could be comparable to the
strength of the RKKY coupling. The dynamical coupling with the intristic RKKY
coupling enables to construct a four level system of maximally entangled Bell
states in a controllable manner.


title: On the nature of laminar-turbulence intermittency in shear flows

abstract:
  In pipe, channel and boundary layer flows turbulence first occurs
intermittently in space and time: at moderate Reynolds numbers domains of
disordered turbulent motion are separated by quiescent laminar regions. Based
on direct numerical simulations of pipe flow we here argue that the spatial
intermittency has its origin in a nearest neighbor interaction between
turbulent regions. We further show that in this regime turbulent flows are
intrinsically intermittent with a well defined equilibrium turbulent fraction
but without ever assuming a steady pattern. This transition scenario is
analogous to that found in simple models such as coupled map lattices. The
scaling observed implies that laminar intermissions of the turbulent flow will
persist to arbitrarily large Reynolds numbers.


title:
Effects of charging and electric field on the properties of silicene and
  germanene

abstract:
  Using first-principles Density Functional Theory calculations, we showed that
electronic and magnetic properties of bare and Ti adatom adsorbed single-layer
silicene and germanene, which are charged or exerted by a perpendicular
electric field are modified to attain new functionalities. In particular, when
exerted by a perpendicular electric field, the symmetry between the planes of
buckled atoms is broken to open a gap at the Dirac points. The occupation of
3d-orbitals of adsorbed Ti atom changes with charging or applied electric field
to induce significant changes of magnetic moment. We predict that neutral
silicene uniformly covered by Ti atoms becomes a half-metal at a specific value
of coverage and hence allows the transport of electrons in one spin direction,
but blocks the opposite direction. These calculated properties, however exhibit
a dependence on the size of the vacuum spacing between periodically repeating
silicene and germanene layers, if they are treated using plane wave basis set
within periodic boundary condition. We clarified the cause of this spurious
dependence and show that it can be eliminated by the use of local orbital basis
set.

categories: cond-mat.mes-hall cond-mat.mtrl-sci physics.chem-ph physics.comp-ph


title:
Abelian and non-Abelian gauge fields in dipole-dipole interacting
  Rydberg atoms

abstract:
  We show that the dipole-dipole interaction between two Rydberg atoms can lead
to substantial Abelian and non-Abelian gauge fields acting on the relative
motion of the two atoms. We demonstrate how the gauge fields can be evaluated
by numerical techniques. In the case of adiabatic motion in a single internal
state, we show that the gauge fields give rise to a magnetic field that results
in a Zeeman splitting of the rotational states. In particular, the ground state
of a molecular potential well is given by the first excited rotational state.
We find that our system realises a synthetic spin-orbit coupling where the
relative atomic motion couples to two internal two-atom states. The associated
gauge fields are non-Abelian.


title: Prehistoric sanctuaries in Daunia

abstract:
  Daunia is a region in northern Apulia with many interesting archaeological
sites, particularly of the Neolithic and Bronze Age. Beginning from the fifth
millennium BC, the farmers living in the wide plain of Daunia dug hypogea and
holes in sites that could be considered prehistoric sanctuaries. The
characteristics of the rows of holes indicate a ritual use, and the
archaeologists tend to exclude other applications, such as post holes and
cultivations. The rows have possibly an astronomical orientation, and in the
sanctuary discovered near Ordona, some stars of the Centaurus-Crux group (may
be alpha Centauri itself) could have been used as targets. In past centuries,
astronomers and scholars have remarked this spectacular region of the sky, and
its possible relevance for the ancient civilizations was pointed out for
example by G.V. Schiaparelli in 1903. In his work on the astronomy in the Old
Testament, he mentioned in particular the observations of the astronomer W.S.
Jacob and of other scholars. It would be probably worth to make simulations in
order to reproduce the 'Jacob effect', that is the diffused light (a sort of
faint twilight) produced by such very rich stellar region of the sky.


title: High-frequency vibrational density of states of a disordered solid

abstract:
  We investigate the high-frequency behavior of the density of vibrational
states in three-dimensional elasticity theory with spatially fluctuating
elastic moduli. At frequencies well above the mobility edge, instanton
solutions yield an exponentially decaying density of states. The instanton
solutions describe excitations, which become localized due to the
disorder-induced fluctuations, which lower the sound velocity in a finite
region compared to its average value. The exponentially decaying density of
states (known in electronic systems as the Lifshitz tail) is governed by the
statistics of a fluctuating-elasticity landscape, capable of trapping the
vibrational excitations.


title: Staggered grid leap-frog scheme for the (2+1)D Dirac equation

abstract:
  A numerical scheme utilizing a grid which is staggered in both space and time
is proposed for the numerical solution of the (2+1)D Dirac equation in presence
of an external electromagnetic potential. It preserves the linear dispersion
relation of the free Weyl equation for wave vectors aligned with the grid and
facilitates the implementation of open (absorbing) boundary conditions via an
imaginary potential term. This explicit scheme has second order accuracy in
space and time. A functional for the norm is derived and shown to be conserved.
Stability conditions are derived. Several numerical examples, ranging from
generic to specific to textured topological insulator surfaces, demonstrate the
properties of the scheme which can handle general electromagnetic potential
landscapes.


title: The one-dimensional Ly-alpha forest power spectrum from BOSS

abstract:
  We have developed two independent methods to measure the one-dimensional
power spectrum of the transmitted flux in the Lyman-$\alpha$ forest. The first
method is based on a Fourier transform, and the second on a maximum likelihood
estimator. The two methods are independent and have different systematic
uncertainties. The determination of the noise level in the data spectra was
subject to a novel treatment, because of its significant impact on the derived
power spectrum.
  We applied the two methods to 13,821 quasar spectra from SDSS-III/BOSS DR9
selected from a larger sample of over 60,000 spectra on the basis of their high
quality, large signal-to-noise ratio, and good spectral resolution. The power
spectra measured using either approach are in good agreement over all twelve
redshift bins from $<z> = 2.2$ to $<z> = 4.4$, and scales from 0.001
$\rm(km/s)^{-1}$ to $0.02 \rm(km/s)^{-1}$. We determine the methodological and
instrumental systematic uncertainties of our measurements.
  We provide a preliminary cosmological interpretation of our measurements
using available hydrodynamical simulations. The improvement in precision over
previously published results from SDSS is a factor 2--3 for constraints on
relevant cosmological parameters. For a $\Lambda$CDM model and using a
constraint on $H_0$ that encompasses measurements based on the local distance
ladder and on CMB anisotropies, we infer $\sigma_8 =0.83\pm0.03$ and $n_s=
0.97\pm0.02$ based on \ion{H}{i} absorption in the range $2.1<z<3.7$.


title:
Generalized Universality of Definite Rank Gluon Transverse Momentum
  Dependent Correlators

abstract:
  Transverse momentum dependent (TMD) parton correlators describing the
partonic structure of hadrons contain gauge links, required by color gauge
invariance. The required gauge links enter in the matrix elements that contain
the parton fields and depend on the color flow in the hard process. The
correlators are expanded in terms of transverse momentum dependent parton
distribution functions, referred to as TMD PDFs, or in short TMDs. In this
paper, we introduce gluon TMDs of definite rank, by making an expansion of the
TMD gluon correlator with the help of irreducible tensors built from the
transverse momenta. The process dependence is isolated in gauge link dependent
gluonic pole factors multiplying the TMDs. It is important to account for the
different possibilities in the color structure within the matrix elements,
leading to multiple TMDs at a given rank. In this way we are able to write the
leading tree level result for a hard process in terms of process dependent
gluon correlators which are expressed in a finite set of universal TMDs. We
tabulate the gluonic pole factors for various gauge links, among them those
that are relevant for 2 to 2 processes.


title:
A Grammatical Inference Approach to Language-Based Anomaly Detection in
  XML

abstract:
  False-positives are a problem in anomaly-based intrusion detection systems.
To counter this issue, we discuss anomaly detection for the eXtensible Markup
Language (XML) in a language-theoretic view. We argue that many XML-based
attacks target the syntactic level, i.e. the tree structure or element content,
and syntax validation of XML documents reduces the attack surface. XML offers
so-called schemas for validation, but in real world, schemas are often
unavailable, ignored or too general. In this work-in-progress paper we describe
a grammatical inference approach to learn an automaton from example XML
documents for detecting documents with anomalous syntax.
  We discuss properties and expressiveness of XML to understand limits of
learnability. Our contributions are an XML Schema compatible lexical datatype
system to abstract content in XML and an algorithm to learn visibly pushdown
automata (VPA) directly from a set of examples. The proposed algorithm does not
require the tree representation of XML, so it can process large documents or
streams. The resulting deterministic VPA then allows stream validation of
documents to recognize deviations in the underlying tree structure or
datatypes.


title: Honest and adaptive confidence sets in Lp

abstract:
  We consider the problem of constructing honest and adaptive confidence sets
in Lp-loss (with p>=1 and p < infinity) over sets of Sobolev-type classes, in
the setting of non-parametric Gaussian regression. The objective is to adapt
the diameter of the confidence sets with respect to the smoothness degree of
the underlying function, while ensuring that the true function lies in the
confidence interval with high probability.When p >=2, we identify two main
regimes, (i) one where adaptation is possible without any restrictions on the
model, and (ii) one where critical regions have to be removed. We also prove by
a matching lower bound that the size of the regions that we remove can not be
chosen significantly smaller. These regimes are shown to depend in a
qualitative way on the index p, and a continuous transition from p = 2 to p =
infinity is exhibited.


title:
WSLD operators II: the new fourth order difference approximations for
  space Riemann-Liouville derivative

abstract:
  High order discretization schemes play more important role in fractional
operators than classical ones. This is because usually for classical
derivatives the stencil for high order discretization schemes is wider than low
order ones; but for fractional operators the stencils for high order schemes
and low order ones are the same. Then using high order schemes to solve
fractional equations leads to almost the same computational cost with first
order schemes but the accuracy is greatly improved. Using the fractional linear
multistep methods, Lubich obtains the $\nu$-th order ($\nu\leq 6$)
approximations of the $\alpha$-th derivative ($\alpha>0$) or integral
($\alpha<0) [Lubich, SIAM J. Math. Anal., 17, 704-719, 1986], because of the
stability issue the obtained scheme can not be directly applied to the space
fractional operator with $\alpha \in(1,2)$ for time dependent problem. By
weighting and shifting Lubich's 2nd order discretization scheme, in [Chen &
Deng, arXiv:1304.7425] we derive a series of effective high order
discretizations for space fractional derivative, called WSLD opeartors there.
As the sequel of the previous work, we further provide new high order schemes
for space fractional derivatives by weighting and shifting Lubich's 3rd and 4th
order discretizations. In particular, we prove that the obtained 4th order
approximations are effective for space fractional derivatives. And the
corresponding schemes are used to solve the space fractional diffusion equation
with variable coefficients.


title: Electroweak bremsstrahlung in bino-like dark matter annihilations

abstract:
  We investigate the effects of electroweak bremsstrahlung on bino-like
neutralino dark matter pair annihilations in the minimal supersymmetric
standard model (MSSM). We calculate the nonrelativistic pair annihilation cross
sections via $W$-strahlung from leptonic final states, $\chi\chi$ $\to$
$W\ell\bar{\nu}$, and compare them with the contributions of the relevant
two-body final states. We explore the case that sleptons lie below the TeV
scale, while squarks are extremely heavy. It is found that the electroweak
bremsstrahlung can give a dominant contribution to the cross section for some
parameter regions which include slepton coannihilation regions with the
observed relic abundance. We also evaluate the neutrino spectra at injection in
the Sun. It is shown that energetic neutrinos via weak bremsstrahlung processes
can be dominant over contributions of the two-body final states.


title:
Collision-Induced Dissociation Studies on Fe(O2)n+ (n=1-6) Clusters:
  Application of a New Technique Based on Crossed Molecular Beams

abstract:
  Gas-phase oxygen-rich iron oxide clusters Fe(O2)n+ (n=1-6), are produced in a
molecular beam apparatus. Their stability and structure are investigated by
measuring the fragmentation cross sections from collision-induced-dissociation
experiments. For this purpose, two different techniques have been employed. The
first one relies on the measurement of the fragments resulting after
collisional activation and subsequent dissociation of mass selected cluster
ions in a molecular beam passing through a cell filled with noble gas atoms.
The second one is a new approach that we introduce and is based on crossed
molecular beams to measure the fragmentation cross sections, in a more
efficient manner without mass selection of the individual clusters. The cross
sections obtained with the different techniques are compared with each other as
well as with theoretical ones resulting from the application of a simple
geometrical projection model. Finally, the general trends observed are compared
with results for other Fe-molecule clusters available in the literature.


title: Generalized interaction in multigravity

abstract:
  A general approach to description of multigravity models in D-dimensional
space-time is presented. Different possibilities of generalization of the
invariant volume are given. Then a most general form of the interaction
potential is constructed, which for bigravity coincides with the Pauli-Fierz
model. A thorough analysis of the model along the 3+1 expansion formalism is
done. It is shown that the absence of ghosts the considered bigravity model is
equivalent in the weak field limit to the massive gravity (the Pauli-Fierz
model). Thus, on the concrete example it is shown, that the interaction between
metrics leads to nonvanishing mass of graviton.


title: V0784 Ophiuchi: an RR Lyrae star with multiple Blazhko modulations

abstract:
  The results of an observation campaign of V0784 Ophiuchi over a time span of
two years have revealed a multi-periodic Blazhko effect. A Blazhko effect for
V0784 Ophiuchi has not been reported previously. From the observed light
curves, 60 pulsation maxima have been measured. The Fourier analyses of the
(O-C) values and of magnitudes at maximum light have revealed a main Blazhko
period of 24.51 days but also two other secondary Blazhko modulations with
periods of 34.29 and 31.07 days. A complete light curve Fourier analysis with
PERIOD04 has shown triplet structures based on main and secondary Blazhko
frequencies close to the reciprocal of Blazhko periods measured from the 60
pulsation maxima.


title: New Phase transitions of the Ising model on Cayley trees

abstract:
  We show that the nearest neighbors Ising model on the Cayley tree exhibits
new temperature driven phase transitions. These transitions holds at various
inverse temperatures different from the critical one. They are depicted by a
change in the number of Gibbs states as well as by a drastic change of the
behavior of free energies at these new transition points.


title:
Backpropagation Imaging in Nonlinear Harmonic Holography in the Presence
  of Measurement and Medium Noises

abstract:
  In this paper, the detection of a small reflector in a randomly heterogenous
medium using second-harmonic generation is investigated. The medium is
illuminated by a time-harmonic plane wave at frequency omega. It is assumed
that the reflector has a non-zero second-order nonlinear susceptibility, and
thus emits a wave at frequency two omega in addition to the fundamental
frequency linear scattering. It is shown how the fundamental frequency signal
and the second-harmonic signal propagate in the medium. A statistical study of
the images obtained by migrating the boundary data is performed. It is proved
that the second-harmonic image is more stable with respect to medium noise than
the one obtained with the fundamental signal. Moreover, the signal-to-noise
ratio for the second-harmonic image does not depend neither on the second-order
susceptibility tensor nor on the volume of the particle.


title: High-energy fluxes of atmospheric neutrinos

abstract:
  High-energy neutrinos from decays of mesons, produced in collisions of cosmic
ray particles with air nuclei, form unavoidable background for detection of
astrophysical neutrinos. More precise calculations of the high-energy neutrino
spectrum are required since measurements in the IceCube experiment reach the
intriguing energy region where a contribution of the prompt neutrinos and/or
astrophysical ones should be discovered. Basing on the referent hadronic models
QGSJET II-03, SIBYLL 2.1, we calculate high-energy spectra, both of the muon
and electron atmospheric neutrinos, averaged over zenith-angles. The
computation is made using three parameterizations of cosmic ray spectra which
include the knee region. All calculations are compared with the atmospheric
neutrino measurements by Frejus and IceCube. The prompt neutrino flux
predictions obtained with thequark-gluon string model (QGSM) for the charm
production by Kaidalov & Piskunova do not contradict to the IceCube
measurements and upper limit on the astrophysical muon neutrino flux. Neutrino
flavor ratio, $\phi_{\nu_ mu}/\phi_{\nu_e}$, extracted from IceCube data
decreases in the energy range $0.1 - 5$ TeV energy contrary to that one might
expect from the conventional neutrino flux. Presumable reasons of such behavior
are: i) early arising contribution from decays of charmed particle, differing
from predictions of present models, ii) revealed diffuse flux of astrophysical
electron neutrinos. The likely diffuse flux of astrophysical neutrinos related
to the PeV neutrino events, detected in the IceCube experiment, leads to a
decrease of the flavor ratio at the energy below 10 TeV, that is in qualitative
agreement with a rough approximation for theflavor ratio obtained from the
IceCube data.


title:
Variability survey in the CoRoT SRa01 field: Implications of eclipsing
  binary distribution on cluster formation in NGC 2264

abstract:
  Time-series photometry of the CoRoT field SRa01 was carried out with the
Berlin Exoplanet Search Telescope II (BEST II) in 2008/2009. A total of 1,161
variable stars were detected, of which 241 were previously known and 920 are
newly found. Several new, variable young stellar objects have been discovered.
The study of the spatial distribution of eclipsing binaries revealed the higher
relative frequency of Algols toward the center of the young open cluster NGC
2264. In general Algol frequency obeys an isotropic distribution of their
angular momentum vectors, except inside the cluster, where a specific
orientation of the inclinations is the case. We suggest that we see the orbital
plane of the binaries almost edge-on.


title: Unavodiable collections of balls for isotropic L\'{e}vy processes

abstract:
  A collection $\{\bar{B}(x_n,r_n)\}_{n\ge 1}$ of pairwise disjoint balls in
the Euclidean space $\R^d$ is said to be avoidable with respect to a transient
process $X$ if the process with positive probability escapes to infinity
without hitting any ball. In this paper we study sufficient and necessary
conditions for avoidability with respect to unimodal isotropic L\'evy processes
satisfying a certain scaling hypothesis. These conditions are expressed in
terms of the characteristic exponent of the process, or alternatively, in terms
of the corresponding Green function. We also discuss the same problem for a
random collection of balls. The results are generalization of several recent
results for the case of Brownian motion.


title: The Schwarzian Curvature

abstract:
  We start with introducing one of the most fundamental notions of differential
geometry, Manifolds. We present some properties and constructions such as
submanifolds, tangent spaces and the tangent map. Then we continue with
introducing the real and complex projective space, and describe them from some
different points of view. This part is finished by showing that CP^n is a
Grassmannian manifold. At this stage we are ready to present the main subject
of this thesis. The Schwarzian curvature, usually seems to be an accidental
by-product of the calculations, can be seen as a geometric interpretation of
the Schwarzian derivative. Flanders interpreted the Schwarzian derivative of a
C''' function as a curvature for curves in the projective line by using the
moving frame method of Cartan. The same argumentation was extended by Gao to
obtain the Schwarzian curvatures for curves in higher dimensional projective
spaces. I give detailed presentation of Gao's work, where he presented the
general formulas for the Schwarzian curvatures for curves in CP^n and gives
some properties for the behaviour of the formulas, for example the
transformation rules under change of coordinates. The Schwarzian curvatures for
curves in CP, CP^2 and CP^3 are calculated, and some examples are given.


title:
A unique method to evaluate the general integral $\int_0^\infty
  dx\frac{\sin ^a px \cos ^c qx}{x^b} $

abstract:
  All integrals available in literature and books, that are related to
Sinc(=sin x/x) function, are special cases of the general form of the integral
given in the title. The evaluation of the integral is divided into two cases
(i) $a$ and $b$ of same parity, which is easier to evaluate and (ii) $a$ and
$b$ of different parity, a difficult case. Amazingly and may be for the first
time, a divergent integral is used in evaluating this difficult case with the
help of a simple but a special combinatorial expression. The combinatorial
identity is derived from the power reduction formula of the Sines and Cosines.
The method adopted in this paper is unique and makes it relatively easy to
evaluate this integral.


title: X-ray transition yields of low-Z kaonic atoms produced in Kapton

abstract:
  The X-ray transition yields of kaonic atoms produced in Kapton polyimide
(C22H10N2O5) were measured for the first time in the SIDDHARTA experiment.
X-ray yields of the kaonic atoms with low atomic numbers (Z = 6, 7, and 8) and
transitions with high principal quantum numbers (n = 5-8) were determined. The
relative yield ratios of the successive transitions and those of
carbon-to-nitrogen (C:N) and carbon-to-oxygen (C:O) were also determined. These
X-ray yields provide important information for understanding the capture ratios
and cascade mechanisms of kaonic atoms produced in a compound material, such as
Kapton.


title: Mean-Field Optimal Control

abstract:
  We introduce the concept of {\it mean-field optimal control} which is the
rigorous limit process connecting finite dimensional optimal control problems
with ODE constraints modeling multi-agent interactions to an infinite
dimensional optimal control problem with a constraint given by a PDE of
Vlasov-type, governing the dynamics of the probability distribution of
interacting agents. While in the classical mean-field theory one studies the
behavior of a large number of small individuals {\it freely interacting} with
each other, by simplifying the effect of all the other individuals on any given
individual by a single averaged effect, we address the situation where the
individuals are actually influenced also by an external {\it policy maker}, and
we propagate its effect for the number $N$ of individuals going to infinity. On
the one hand, from a modeling point of view, we take into account also that the
policy maker is constrained to act according to optimal strategies promoting
its most parsimonious interaction with the group of individuals. This will be
realized by considering cost functionals including $L^1$-norm terms penalizing
a broadly distributed control of the group, while promoting its sparsity. On
the other hand, from the analysis point of view, and for the sake of
generality, we consider broader classes of convex control penalizations. In
order to develop this new concept of limit rigorously, we need to carefully
combine the classical concept of mean-field limit, connecting the finite
dimensional system of ODE describing the dynamics of each individual of the
group to the PDE describing the dynamics of the respective probability
distribution, with the well-known concept of $\Gamma$-convergence to show that
optimal strategies for the finite dimensional problems converge to optimal
strategies of the infinite dimensional problem.


title: A Gauge Field Model of Modal Completion

abstract:
  Perceptual completion of figures is a basic process revealing the deep
architecture of low level vision. In this paper a complete gauge field
Lagrangian is proposed allowing to couple the retinex equation with
neurogeometrical models and to solve the problem of modal completion, i.e. the
pop up of the Kanizsa triangle. Euler-Lagrange equations are derived by
variational calculus and numerically solved. Plausible neurophysiological
implementations of the particle and field equations are discussed and a model
of the interaction between LGN and visual cortex is proposed.


title: Phonon Cooling and Lasing with Nitrogen-Vacancy Centers in Diamond

abstract:
  We investigate the strain-induced coupling between a nitrogen-vacancy
impurity and a resonant vibrational mode of a diamond nanoresonator. We show
that under near-resonant laser excitation of the electronic states of the
impurity, this coupling can modify the state of the resonator and either cool
the resonator close to the vibrational ground state or drive it into a large
amplitude coherent state. We derive a semi-classical model to describe both
effects and evaluate the stationary state of the resonator mode under various
driving conditions. In particular, we find that by exploiting resonant single
and multi-phonon transitions between near-degenerate electronic states, the
coupling to high-frequency vibrational modes can be significantly enhanced and
dominate over the intrinsic mechanical dissipation. Our results show that a
single nitrogen-vacancy impurity can provide a versatile tool to manipulate and
probe individual phonon modes in nanoscale diamond structures.


title:
Jahn-Teller, polarity and insulator-to-metal transition in BiMnO3 at
  high pressure

abstract:
  The interaction of coexisting structural instabilities in multiferroic
materials gives rise to intriguing coupling phenomena and extraordinarily rich
phase diagrams, both in bulk materials and strained thin films. Here we
investigate the multiferroic BiMnO3 with its peculiar 6s2 electrons and four
interacting mechanisms: electric polarity, octahedra tilts, magnetism, and
cooperative Jahn-Teller distortion. We have probed structural transitions under
high pressure by synchrotron x-ray diffraction and Raman spectroscopy up to 60
GPa. We show that BiMnO3 displays under pressure a rich sequence of five phases
with a great variety of structures and properties, including a metallic phase
above 53 GPa and, between 37 and 53 GPa, a strongly elongated monoclinic phase
that allows ferroelectricity, which contradicts the traditional expectation
that ferroelectricity vanishes under pressure. Between 7 and 37 GPa, the Pnma
structure remains remarkably stable but shows a reduction of the Jahn-Teller
distortion in a way that differs from the behavior observed in the archetypal
orthorhombic Jahn-Teller distorted perovskite LaMnO3.


title:
Upper bounds on the non-random fluctuations in first passage percolation
  with low moment conditions

abstract:
  We consider first passage percolation with i.i.d. weights on edges of the
d-dimensional cubic lattice. Under the assumptions that a weight is equal to
zero with probability smaller than the critical probability of bond percolation
in the d-dimensional cubic lattice, and has moments bigger than 1, we
investigate upper bounds on the so-called non-random fluctuations of the model.
In addition, we give an application of our result to a lower bound for variance
of the first passage percolation in the case where the limit shape has flat
edges.


title:
A Randomized Nonmonotone Block Proximal Gradient Method for a Class of
  Structured Nonlinear Programming

abstract:
  We propose a randomized nonmonotone block proximal gradient (RNBPG) method
for minimizing the sum of a smooth (possibly nonconvex) function and a
block-separable (possibly nonconvex nonsmooth) function. At each iteration,
this method randomly picks a block according to any prescribed probability
distribution and solves typically several associated proximal subproblems that
usually have a closed-form solution, until a certain progress on objective
value is achieved. In contrast to the usual randomized block coordinate descent
method [23,20], our method has a nonmonotone flavor and uses variable stepsizes
that can partially utilize the local curvature information of the smooth
component of objective function. We show that any accumulation point of the
solution sequence of the method is a stationary point of the problem {\it
almost surely} and the method is capable of finding an approximate stationary
point with high probability. We also establish a sublinear rate of convergence
for the method in terms of the minimal expected squared norm of certain
proximal gradients over the iterations. When the problem under consideration is
convex, we show that the expected objective values generated by RNBPG converge
to the optimal value of the problem. Under some assumptions, we further
establish a sublinear and linear rate of convergence on the expected objective
values generated by a monotone version of RNBPG. Finally, we conduct some
preliminary experiments to test the performance of RNBPG on the
$\ell_1$-regularized least-squares problem and a dual SVM problem in machine
learning. The computational results demonstrate that our method substantially
outperforms the randomized block coordinate {\it descent} method with fixed or
variable stepsizes.


title: From p+p to Pb+Pb Collisions: Wounded Nucleon versus Statistical Models

abstract:
  System size dependence of hadron production properties is discussed within
the Wounded Nucleon Model and the Statistical Model in the grand canonical,
canonical and micro-canonical formulations. Similarities and differences
between predictions of the models related to the treatment of conservation laws
are exposed. A need for models which would combine a hydrodynamical-like
expansion with conservation laws obeyed in individual collisions is stressed.


title: Sandwiched R\'enyi Divergence Satisfies Data Processing Inequality

abstract:
  Sandwiched (quantum) $\alpha$-R\'enyi divergence has been recently defined in
the independent works of Wilde et al. (arXiv:1306.1586) and M\"uller-Lennert et
al (arXiv:1306.3142v1). This new quantum divergence has already found
applications in quantum information theory. Here we further investigate
properties of this new quantum divergence. In particular we show that
sandwiched $\alpha$-R\'enyi divergence satisfies the data processing inequality
for all values of $\alpha> 1$. Moreover we prove that $\alpha$-Holevo
information, a variant of Holevo information defined in terms of sandwiched
$\alpha$-R\'enyi divergence, is super-additive. Our results are based on
H\"older's inequality, the Riesz-Thorin theorem and ideas from the theory of
complex interpolation. We also employ Sion's minimax theorem.


title: The width of the omega meson in the nuclear medium

abstract:
  We evaluate the width of the $\omega$ meson in nuclear matter. We consider
the free decay mode of the $\omega$ into three pions, which is dominated by
$\rho \pi$ decay, and replace the $\rho$ and $\pi$ propagators by their medium
modified ones. We also take into account the quasielastic and inelastic
processes induced by a vector-baryon interaction dominated by vector meson
exchange, as well as the contributions coming from the $\omega \to K \bar K$
mechanism with medium modified $K$, $\bar K$ propagators. We obtain a
substantial increase of the $\omega$ width in the medium, reaching a value of
$129 \pm 10$ MeV at normal nuclear matter density for an $\omega$ at rest,
which comes mainly from $\omega N \to \pi \pi N, \omega N N \to \pi NN$
processes associated to the dominant $\omega \to \rho\pi$ decay mode. The value
of the width increases moderately with momentum, reaching values of around 200
MeV at 600 MeV/c.


title: Leptonic Dynamical Yukawa Couplings

abstract:
  A dynamical origin of the Yukawa couplings is a promising scenario to explain
the flavour puzzle. The focus of this letter is set on the role of the neutrino
Majorana character: when an $O(2)_{N_R}$ flavour symmetry acts on the
right-handed neutrino sector, the minimum of the scalar potential allows for
large mixing angles -in contrast to the simplest quark case- and predicts a
maximal Majorana phase. This leads to a strong correlation between neutrino
mass hierarchy and mixing pattern. Realistic solutions point to the existence
of three heavy right-handed neutrinos.


title:
Noise reduction methods in analysis of near infrared lunar occultation
  light curves for high angular resolution measurements

abstract:
  Lunar occultation (LO) technique in the near-infrared provides angular
resolution down to milliarcseconds on the occulted source even with
ground-based 1m class telescopes. LO observations are limited to brighter
objects because they require high signal to noise ratio (S/N ~ 40) for proper
extraction of angular diameter values. Hence, methods to improve the S/N ratio
by reducing noise using Fourier and Wavelet transforms have been explored in
this study. A sample of 54 near-infrared LO light curves observed with IR
Camera at Mt Abu observatory has been used. It is seen that both Fourier and
Wavelet methods have shown improvement in S/N, compared to the original data.
However, the application of wavelet transforms results in slight smoothening of
the fringes resulting in a higher angular diameter value. Fourier transforms
which reduce discrete noise frequencies do not distort the fringe. Fourier
transform method seems to be effective in S/N improvement, as well as improved
model fit particularly in the fainter regime of our sample. They also provide a
better model fit for brighter sources in some cases though there may not be
significant S/N improvement.


title: Designing a Spin-Seebeck Diode

abstract:
  Using micromagnetic simulations, we have investigated spin dynamics in a
spin-valve bi-layer in the presence of a thermal gradient. The direction and
the intensity of the gradient allow to excite the spin wave modes of each layer
selectively. This permits to synchronize the magnetization precession of the
two layers and to rectify the flows of energy and magnetization through the
system. Our study yields promising opportunities for applications in spin
caloritronics and nanophononics devices.


title:
The influence of oxygen and hydrogen adsorption on the magnetic
  structure of the ultrathin iron film on the Ir(001) surface

abstract:
  We present a detailed ab initio study of the electronic structure and
magnetic order of an Fe monolayer on the Ir(001) surface covered by adsorbed
oxygen and hydrogen. The results are compared to the clean Fe/Ir(001) system,
where recent intensive studies indicated a strong tendency towards an
antiferromagnetic order and complex magnetic structures. The adsorption of an
oxygen overlayer significantly increases interlayer distance between the Fe
layer and the Ir substrate, while the effect of hydrogen is much weaker. We
show that the adsorption of oxygen (and also of hydrogen) leads to a p(2$\times
$1) antiferromagnetic order of the Fe moments, which is also supported by an
investigation based on a disordered local moment state. Simulated scanning
tunneling images using the simple Tersoff-Hamann model hint that the proposed
p(2$\times $1) antiferromagnetic order could be detected even by non-magnetic
tips.


title: On the M\"obius Function of Permutations With One Descent

abstract:
  The set of all permutations, ordered by pattern containment, is a poset. We
give a formula for the M\"obius function of intervals $[1,\pi]$ in this poset,
for any permutation $\pi$ with at most one descent. We compute the M\"obius
function as a function of the number and positions of pairs of consecutive
letters in $\pi$ that are consecutive in value. As a result of this we show
that the M\"obius function is unbounded on the poset of all permutations. We
show that the M\"obius function is zero on any interval $[1,\pi]$ where $\pi$
has a triple of consecutive letters whose values are consecutive and monotone.
We also conjecture values of the M\"obius function on some other intervals of
permutations with at most one descent.


title: Neutrino Mixing and Masses from a Minimum Principle

abstract:
  We analyze the structure of quark and lepton mass matrices under the
hypothesis that they are determined from a minimum principle applied to a
generic potential invariant under the $\left[SU(3)\right]^5\otimes \mathcal
O(3)$ flavor symmetry, acting on Standard Model fermions and right-handed
neutrinos. Unlike the quark case, we show that hierarchical masses for charged
leptons are naturally accompanied by degenerate Majorana neutrinos with one
mixing angle close to maximal, a second potentially large, a third one
necessarily small, and one maximal relative Majorana phase. Adding small
perturbations the predicted structure for the neutrino mass matrix is in
excellent agreement with present observations and could be tested in the near
future via neutrino-less double beta decay and cosmological measurements. The
generalization of these results to arbitrary sew-saw models is also discussed.


title: Accurate estimates of asymptotic indices via fractional calculus

abstract:
  We devise a three-parameter random search strategy to obtain accurate
estimates of the large-coupling amplitude and exponent of an observable from
its divergent Taylor expansion, known to some desired order. The endeavor
exploits the power of fractional calculus, aided by an auxiliary series and
subsequent construction of Pad\'e approximants. Pilot calculations on the
ground-state energy perturbation series of the octic anharmonic oscillator
reveal the spectacular performance.


title: Perfect powers in Catalan and Narayana numbers

abstract:
  When a Catalan number or a Narayana number is a (non-trivial) perfect power?
For Catalan numbers, we show that the answer is "never". However, we prove that
for every b, the Narayana number N(a,b) is a (non-trivial) perfect square for
infinitely many values of a, and we show how to compute all of them. We also
conjecture that N(a,b) is never a (non-trivial) perfect k-th power for k
greater than 2 and we prove some cases of this conjecture.


title: The Green Language

abstract:
  Green is a statically-typed object-oriented language that separates subtyping
from inheritance. It supports garbage collection, classes as first-class
objects, parameterized classes, introspective reflection and a kind of run-time
metaobjects called shells.