title:
Effects of grain growth mechanisms on the extinction curve and the metal
  depletion in the interstellar medium

abstract:
  Dust grains grow their sizes in the interstellar clouds (especially in
molecular clouds) by accretion and coagulation. Here we model and test these
processes by examining the consistency with the observed variation of the
extinction curves in the Milky Way. We find that, if we simply use the
parameters used in previous studies, the model fails to explain the flattening
of far-UV extinction curve for large $R_V$ (flatness of optical extinction
curve) and the existence of carbon bump even in flat extinction curves. This
discrepancy is resolved by adopting a `tuned' model, in which coagulation of
carbonaceous dust is less efficient (by a factor of 2) and that of silicate is
more efficient with the coagulation threshold removed. The tuned model is also
consistent with the relation between silicon depletion (indicator of accretion)
and $R_V$ if the duration of accretion and coagulation is >100(n_H/10^3
cm^{-3})^{-1} Myr, where n_H is the number density of hydrogen nuclei in the
cloud. We also examine the relations between each of the extinction curve
features (UV slope, far-UV curvature, and carbon bump strength) and $R_V$. The
correlation between UV slope and $R_V$, which is the strongest among the three
correlations, is well reproduced by the tuned model. For far-UV curvature and
carbon bump strength, the observational data are located between the tuned
model and the original model without tuning, implying that the large scatters
in the observational data can be explained by the sensitive response to the
coagulation efficiency. The overall success of the tuned model indicates that
accretion and coagulation are promising mechanisms of producing the variation
of extinction curves in the Milky Way, although we do not exclude possibilities
of other dust-processing mechanisms changing extinction curves.


title:
Structure theorems for bicomodule algebras over quasi-Hopf algebras,
  weak Hopf algebras and braided Hopf algebras

abstract:
  Let H be a quasi-Hopf algebra, a weak Hopf algebra or a braided Hopf algebra.
Let B be an H-bicomodule algebra such that there exists a morphism of
H-bicomodule algebras v:H\rightarrow B. Then we can define an object B^{co(H)}
which is a left-left Yetter-Drinfeld module over H, having extra properties
that allow to make a smash product B^{co(H)}# H which is an H-bicomodule
algebra, isomorphic to B.


title: Random index of codivisibility

abstract:
  The index of codivisibility of a set of integers is the size of its largest
subset with a common prime divisor. For large random samples of integers, the
index of codivisibility is approximately normal.


title: Solving Fluctuation-Enhanced Poisson-Boltzmann Equations

abstract:
  Electrostatic correlations and fluctuations in ionic systems can be described
within an extended Poisson-Boltzmann theory using a Gaussian variational form.
The resulting equations are challenging to solve because they require the
solution of a non-linear partial differential equation for the pair correlation
function. This has limited existing studies to simple approximations or to
one-dimensional geometries. In this paper we show that the numerical solution
of the equations is greatly simplified by the use of selective inversion of a
finite difference operator which occurs in the theory. This selective inversion
preserves the sparse structure of the problem and leads to substantial savings
in computer effort. In one and two dimensions further simplifications are made
by using a mixture of selective inversion and Fourier techniques.


title: On Generalized Wronskians

abstract:
  The Wro\'nski determinant ({\em Wro\'nskian}), usually introduced in standard
courses in Ordinary Differential Equations (ODE), is a very useful tool in
algebraic geometry to detect ramification loci of linear systems. The present
survey aims to describe some "materializations" of the Wro\'nskian and of its
close relatives, {\it the generalized Wro\'nskians}, in algebraic geometry.
Emphasis will be put on the relationships between Schubert Calculus and Linear
Ordinary Differential Equations.}


title: Orbits of mutually unbiased bases

abstract:
  We express Alltop's construction of mutually unbiased bases as orbits under
the Weyl-Heisenberg group in prime dimensions and find a related construction
in dimensions 2 and 4. We reproduce Alltop's mutually unbiased bases using
abelian subgroups of the Clifford group in prime dimensions, in direct analogy
to the well-known construction of mutually unbiased bases using abelian
subgroups of the Weyl-Heisenberg group. Finally, we prove three theorems
relating to the distances and linear dependencies among different sets of
mutually unbiased bases.


title:
Asymptotic of the terms of the Gegenbauer polynomial on the unit circle
  and applications to the inverse of Toeplitz matrices

abstract:
  The first part of this paper is devoted to the study of the orthogonal
polynomial on the circle, with respect of a weight of type $f_\alpha (\theta) =
(2\cos \theta- 2\cos \theta_0)^{2\alpha} c_1$ with $\theta_0 \in ]0,\pi[$, -1/2
<\alpha<1/2 and c_1 a sufficiently smooth function. In a second part of the
paper we obtain an asymptotic of the entries $(T_N f_\alpha)^{-1}_{k+1,l+1}$
for sufficiently large values of $k,l$, that provides a lower bound on the
eigenvalues of this matrix.


title: The mathematical foundations of gauge theory revisited

abstract:
  We start recalling with critical eyes the mathematical methods used in gauge
theory and prove that they are not coherent with continuum mechanics, in
particular the analytical mechanics of rigid bodies or hydrodynamics, though
using the same group theoretical methods and despite the well known couplings
existing between elasticity and electromagnetism (piezzoelectricity,
photoelasticity, streaming birefringence). The purpose of this paper is to
avoid such contradictions by using new mathematical methods coming from the
formal theory of systems of partial differential equations and Lie
pseudogroups. These results finally allow to unify the previous independent
tentatives done by the brothers E. and F. Cosserat in 1909 for elasticity or H.
Weyl in 1918 for electromagnetism by using respectively the group of rigid
motions of space or the conformal group of space-time. Meanwhile we explain why
the Poincar\'{e} "duality scheme" existing between "geometry " and "physics"
has to do with homological algebra and algebraic analysis. We insist on the
fact that these results could not have been obtained before 1975 as the
corresponding tools were not known before and are still not known today by
physicists.


title: Effect of atomic distribution on cooperative spontaneous emission

abstract:
  We study cooperative single-photon spontaneous emission from N multilevel
atoms for different atomic distributions in optical vector theory. Instead of
the average approximation for interatomic distance or the continuum
approximation (sums over atoms replaced by integrals) for atomic distribution,
the positions of every atom are taken into account by numerical calculation. It
is shown that the regularity of atomic distribution has considerable influence
on cooperative spontaneous emission. For a small atomic sample (compared with
radiation wavelength), to obtain strong superradiance not only needs the
uniform excitation (the Dicke state) but also requires the uniform atomic
distribution. For a large sample, the uniform atomic distribution is beneficial
to subradiance of the Dicke state, while the influence of atomic distribution
on the timed Dicke state is weak and its time evolution obeys exponential decay
approximately. In addition, we also investigate the corresponding emission
spectrum and verify the directed emission for the timed Dicke state for a large
atomic sample.


title:
The Hautus Test and Genericity Results for Controllable and
  Uncontrollable Behaviors

abstract:
  This paper generalizes the classical Hautus Test to systems described by
partial differential equations.


title:
Morphological analysis of stylolites for paleostress estimation in
  limestones surrounding the Andra Underground Research Laboratory site

abstract:
  We develop and test a methodology to infer paleostress from the morphology of
stylolites within borehole cores. This non-destructive method is based on the
analysis of the stylolite trace along the outer cylindrical surface of the
cores. It relies on an automatic digitization of high-resolution photographs
and on the spatial Fourier spectrum analysis of the stylolite traces. We test
and show, on both synthetic and natural examples, that the information from
this outer cylindrical surface is equivalent to the one obtained from the
destructive planar sections traditionally used. The assessment of paleostress
from the stylolite morphology analysis is made using a recent theoretical
model, which links the morphological properties to the physical processes
acting during stylolite evolution. This model shows that two scaling regimes
are to be expected for the stylolite height power spectrum, separated by a
cross-over length that depends on the magnitude of the paleostress during
formation. We develop a non linear fit method to automatically extract the
cross-over lengths from the digitized stylolite profiles. Results on cores from
boreholes drilled in the surroundings of the Andra Underground Research
Laboratory located at Bure, France, show that different groups of sedimentary
stylolites can be distinguished, and correspond to different estimated vertical
paleostress values. For the Oxfordian formation, one group of stylolites
indicate a paleostress of around 10 MPa, while another group yields 15 MPa. For
the Dogger formation, two stylolites indicate a paleostress of around 10 MPa,
while others appear to have stopped growing at paleostresses between 30 and 22
MPa, starting at an erosion phase that initiated in the late Cretaceous and
continues today. This method has a high potential for further applications on
reservoirs or other geological contexts where stylolites are present.


title: Existence of Minimizers for the Reifenberg Plateau problem

abstract:
  That is, given a compact set $B \subset \mathbb{R}^n$ (the boundary) and a
subgroup $L$ of the \v{C}ech homology group $\check{H}_{d-1}(B;G)$ of dimension
$d$ over some commutative group $G$, we find a compact set $E \supset B$ such
that the image of $L$ by the natural map
$\check{H}_{d-1}(B;G)\to\check{H}_{d-1}(S;G)$ induced by the inclusion $B \to
E$, is reduced to $\{ 0 \}$, and such that the Hausdorff measure
$\mathcal{H}^{d}(E \setminus B)$ is minimal under these constraints. Thus we
have no restriction on the group $G$ or the dimensions $0 < d < n$.


title: Time from quantum entanglement: an experimental illustration

abstract:
  In the last years several theoretical papers discussed if time can be an
emergent property deriving from quantum correlations. Here, to provide an
insight into how this phenomenon can occur, we present an experiment that
illustrates Page and Wootters' mechanism of "static" time, and Gambini et al.
subsequent refinements. A static, entangled state between a clock system and
the rest of the universe is perceived as evolving by internal observers that
test the correlations between the two subsystems. We implement this mechanism
using an entangled state of the polarization of two photons, one of which is
used as a clock to gauge the evolution of the second: an "internal" observer
that becomes correlated with the clock photon sees the other system evolve,
while an "external" observer that only observes global properties of the two
photons can prove it is static.


title: Challenges in Double Beta Decay

abstract:
  After nearly 80 years since the first guess on its existence, neutrino still
escapes our insight: the mass and the true nature (Majorana or Dirac) of this
particle is still unknown. In the past ten years, neutrino oscillation
experiments have finally provided the incontrovertible evidence that neutrinos
mix and have finite masses. These results represent the strongest demonstration
that the Standard Model of electroweak interactions is incomplete and that new
Physics beyond it must exist. None of these experimental efforts could however
shade light on some of the basic features of neutrinos. Indeed, absolute scale
and ordering of the masses of the three generations as well as charge
conjugation and lepton number conservation properties are still unknown. In
this scenario, a unique role is played by the Neutrinoless Double Beta Decay
searches: these experiments can probe lepton number conservation, investigate
the Dirac/Majorana nature of the neutrinos and their absolute mass scale
(hierarchy problem) with unprecedented sensitivity. Today Neutrinoless Double
Beta Decay faces a new era where large scale experiments with a sensitivity
approaching the so-called degenerate-hierarchy region are nearly ready to start
and where the challenge for the next future is the construction of detectors
characterized by a tonne-scale size and an incredibly low background, to fully
probe the inverted-hierarchy region. A number of new proposed projects took up
this challenge. These are based either on large expansions of the present
experiments or on new ideas to improve the technical performance and/or reduce
the background contributions. n this paper, a review of the most relevant
ongoing experiments is given. The most relevant parameters contributing to the
experimental sensitivity are discussed and a critical comparison of the future
projects is proposed.


title: Novel mid-infrared plasmonic properties of bilayer graphene

abstract:
  We study the mid-infrared plasmonic response in Bernal-stacked bilayer
graphene. Unlike its monolayer counterpart, bilayer graphene accommodates
optically active phonon modes and a resonant interband transition at infrared
frequencies. They strongly modifies the plasmonic properties of bilayer
graphene, leading to Fano-type resonances, giant plasmonic enhancement of
infrared phonon absorption, narrow window of optical transparency, and a new
plasmonic mode at higher energy than the classical plasmon.


title:
Low energy resolvent for the Hodge Laplacian: Applications to Riesz
  transform, Sobolev estimates and analytic torsion

abstract:
  On an asymptotically conic manifold $(M,g)$, we analyze the asymptotics of
the integral kernel of the resolvent $R_q(k):=(\Delta_q+k^2)^{-1}$ of the Hodge
Laplacian $\Delta_q$ on $q$-forms as the spectral parameter $k$ approaches
zero, assuming that 0 is not a resonance. The first application we give is an
$L^p$ Sobolev estimate for $d+\delta$ and $\Delta_q$. Then we obtain a complete
characterization of the range of $p>1$ for which the Riesz transform for
$q$-forms $T_q=(d+\delta)\Delta_q^{-1/2}$ is bounded on $L^p$. Finally, we
obtain an asymptotic formula for the analytic torsion of a family of smooth
compact Riemannian manifolds $(\Omega_\epsilon,g_\epsilon)$ degenerating to a
compact manifold $(\Omega_0,g_0)$ with a conic singularity as $\epsilon\to 0$.


title:
Activation cross-sections of longer-lived products of proton induced
  nuclear reactions on dysprosium up to 36 MeV

abstract:
  Activation cross-sections of longer-lived products of proton induced nuclear
reactions on dysprosium were measured up to 36 MeV by using stacked foil
irradiation technique and gamma-spectrometry. We report for the first time
experimental cross-sections for the formation of the radionuclides 162mHo,
161Ho, 159Ho, 159Dy, 157Dy, 155Dy, 161Tb, 160Tb, 156Tb and 155Tb. The
experimental data were compared with the results of cross-section calculations
of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction
model code as listed in the on-line libraries TENDL 2011 and TENDL 2012.


title:
A new class of topological insulators from I-III-IV half-Heusler
  compounds with strong band inversion strength

abstract:
  In this paper, by first principle calculations, we investigate systematically
the band topology of a new half-Heusler family with composition of
I(A)-III(A)-IV(A). The results clearly show that many of the I-III-IV
half-Heusler compounds are in fact promising to be topological insulator
candidates. The characteristic feature of these new topological insulators is
the naturally strong band inversion strength (up to -2eV) without containing
heavy elements. Moreover, we found that both the band inversion strength and
the topological insulating gap can be tailored through strain engineering, and
therefore would be grown epitaxially in the form of films, and useful in
spintronics and other applications.


title:
Existence and regularity of maximal metrics for the first Laplace
  eigenvalue on surfaces

abstract:
  We investigate in this paper the existence of a metric which maximizes the
first eigenvalue of the Laplacian on Riemannian surfaces. We first prove that,
in a given conformal class, there always exists such a maximizing metric which
is smooth except at a finite set of conical singularities. This result is
similar to the beautiful result concerning Steklov eigenvalues recently
obtained by Fraser and Schoen. Then we get existence results among all metrics
on surfaces of a given genus, leading to the existence of minimal isometric
immersions of smooth compact Riemannian manifold $(M,g)$ of dimension 2 into
some $k$-sphere by first eigenfunctions. At last, we also answer a conjecture
of Friedlander and Nadirashvili which asserts that the supremum of the first
eigenvalue of the Laplacian on a conformal class can be taken as close as we
want of its value on the sphere on any orientable surface.


title: On a rigidity result for the first conformal eigenvalue of the Laplacian

abstract:
  Given $(M,g)$ a smooth compact Riemannian manifold without boundary of
dimension $n\geq 3$, we consider the first conformal eigenvalue which is by
definition the supremum of the first eigenvalue of the Laplacian among all
metrics conformal to $g$ of volume 1. We prove that it is always greater than
$n\omega_n^{\frac{2}{n}}$, the value it takes in the conformal class of the
round sphere, except if $(M,g)$ is conformally diffeomorphic to the standard
sphere.


title: Axisymmetric constant mean curvature slices in the Kerr space-time

abstract:
  Recently, there have been efforts to solve Einstein's equation in the context
of a conformal compactification of space-time. Of particular importance in this
regard are the so called CMC-foliations, characterized by spatial hyperboloidal
hypersurfaces with a constant extrinsic mean curvature K. However, although of
interest for general space-times, CMC-slices are known explicitly only for the
spherically symmetric Schwarzschild metric. This work is devoted to numerically
determining axisymmetric CMC-slices within the Kerr solution. We construct such
slices outside the black hole horizon through an appropriate coordinate
transformation in which an unknown auxiliary function A is involved. The
condition K=const. throughout the slice leads to a nonlinear partial
differential equation for the function A, which is solved with a
pseudo-spectral method. The results exhibit exponential convergence, as is to
be expected in a pseudo-spectral scheme for analytic solutions. As a
by-product, we identify CMC-slices of the Schwarzschild solution which are not
spherically symmetric.


title: Sample and Hold Errors in the Implementation of Chaotic Maps

abstract:
  Though considerable effort has recently been devoted to hardware realization
of chaotic maps, the analysis generally neglects the influence of
implementation inaccuracies. Here we investigate the consequences of S/H errors
on Bernoulli shift, tent map and tailed tent map systems: an error model is
proposed and implementations are characterized under its assumptions.


title: Majorana edge modes in the Kitaev model

abstract:
  We study the Majorana modes, both equilibrium and Floquet, which can appear
at the edges of the Kitaev model on the honeycomb lattice. We first present the
analytical solutions known for the equilibrium Majorana edge modes for both
zigzag and armchair edges of a semi-infinite Kitaev model and chart the
parameter regimes of the model in which they appear. We then examine how edge
modes can be generated if the Kitaev coupling on the bonds perpendicular to the
edge is varied periodically in time as periodic $\delta$-function kicks. We
derive a general condition for the appearance and disappearance of the Floquet
edge modes as a function of the drive frequency for a generic $d$-dimensional
integrable system. We confirm this general condition for the Kitaev model with
a finite width by mapping it to a one-dimensional model. Our numerical and
analytical study of this problem shows that Floquet Majorana modes can appear
on some edges in the kicked system even when the corresponding equilibrium
Hamiltonian has no Majorana mode solutions on those edges. We support our
analytical studies by numerics for finite sized system which show that periodic
kicks can generate modes at the edges and the corners of the lattice.


title: Reliability Models for Highly Fault-tolerant Storage Systems

abstract:
  We found that a reliability model commonly used to estimate
Mean-Time-To-Data-Loss (MTTDL), while suitable for modeling RAID 0 and RAID 5,
fails to accurately model systems having a fault-tolerance greater than 1.
Therefore, to model the reliability of RAID 6, Triple-Replication, or k-of-n
systems requires an alternate technique. In this paper, we explore some
alternatives, and evaluate their efficacy by comparing their predictions to
simulations. Our main result is a new formula which more accurately models
storage system reliability.


title:
Insights into the Phase Diagram of Bismuth Ferrite from Quasi-Harmonic
  Free Energy Calculations

abstract:
  We have used first-principles methods to investigate the phase diagram of
multiferroic bismuth ferrite (BiFeO3 or BFO), revealing the energetic and
vibrational features that control the occurrence of various relevant
structures. More precisely, we have studied the relative stability of four
low-energy BFO polymorphs by computing their free energies within the
quasi-harmonic approximation, introducing a practical scheme that allows us to
account for the main effects of spin disorder. As expected, we find that the
ferroelectric ground state of the material (with R3c space group) transforms
into an orthorhombic paraelectric phase (Pnma) upon heating. We show that this
transition is not significantly affected by magnetic disorder, and that the
occurrence of the Pnma structure relies on its being vibrationally (although
not elastically) softer than the R3c phase. We also investigate a
representative member of the family of nano-twinned polymorphs recently
predicted for BFO [Prosandeev et al., Adv. Funct. Mater. 23, 234 (2013)] and
discuss their possible stabilization at the boundaries separating the R3c and
Pnma regions in the corresponding pressure-temperature phase diagram. Finally,
we elucidate the intriguing case of the so-called super-tetragonal phases of
BFO: Our results explain why such structures have never been observed in the
bulk material, despite their being stable polymorphs of very low energy.
Quantitative comparison with experiment is provided whenever possible, and the
relative importance of various physical effects (zero-point motion, spin
fluctuations, thermal expansion) and technical features (employed
exchange-correlation energy density functional) is discussed. Our work attests
the validity and usefulness of the quasi-harmonic scheme to investigate the
phase diagram of this complex oxide, and prospective applications are
discussed.


title: On a question of Mehta and Pauly

abstract:
  In this short note we provide explicit examples in characteristic $p$ on
certain smooth projective curves where for a given semistable vector bundle
$\mathcal{E}$ the length of the Harder-Narasimhan filtration of $F^\ast
\mathcal{E}$ is longer than $p$. This answers a question of Mehta and Pauly
raised in arXiv:math/0607565.


title: Crossed modules of racks

abstract:
  We generalize the notion of a crossed module of groups to that of a crossed
module of racks. We investigate the relation to categorified racks, namely
strict 2-racks, and trunk-like objects in the category of racks, generalizing
the relation between crossed modules of groups and strict 2-groups. Then we
explore topological applications. We show that by applying the rack-space
functor, a crossed module of racks gives rise to a covering. Our main result
shows how the fundamental racks associated to links upstairs and downstairs in
a covering fit together to form a crossed module of racks.


title:
Optimal input design for non-linear dynamic systems: a graph theory
  approach

abstract:
  In this article a new algorithm for the design of stationary input sequences
for system identification is presented. The stationary input signal is
generated by optimizing an approximation of a scalar function of the
information matrix, based on stationary input sequences generated from prime
cycles, which describe the set of finite Markov chains of a given order. This
method can be used for solving input design problems for nonlinear systems. In
particular it can handle amplitude constraints on the input. Numerical examples
show that the new algorithm is computationally attractive and that is
consistent with previously reported results.


title: Emergence of Blind Areas in Information Spreading

abstract:
  Recently, contagion-based (disease, information, etc.) spreading on social
networks has been extensively studied. In this paper, other than traditional
full interaction, we propose a partial interaction based spreading model,
considering that the informed individuals would transmit information to only a
certain fraction of their neighbors due to the transmission ability in
real-world social networks. Simulation results on three representative networks
(BA, ER, WS) indicate that the spreading efficiency is highly correlated with
the network heterogeneity. In addition, a special phenomenon, namely
\emph{Information Blind Areas} where the network is separated by several
information-unreachable clusters, will emerge from the spreading process.
Furthermore, we also find that the size distribution of such information blind
areas obeys power-law-like distribution, which has very similar exponent with
that of site percolation. Detailed analyses show that the critical value is
decreasing along with the network heterogeneity for the spreading process,
which is complete the contrary to that of random selection. Moreover, the
critical value in the latter process is also larger that of the former for the
same network. Those findings might shed some lights in in-depth understanding
the effect of network properties on information spreading.


title:
Large-Data Global Well-Posedness for the (1 + 2)-Dimensional Equivariant
  Faddeev Model

abstract:
  The Faddeev model is a classical field theory that models heavy elementary
particles by knotted topological solitons. It is a generalization of the
well-known classical nonlinear sigma model of Gell-Mann and Levy, and is also
related closely to the celebrated Skyrme model. The global well-posedness of
the quasilinear PDE arising from this model has been studied intensely in
recent years, both in three and two spatial dimensions. In this paper we
introduce a proof of large-data global well-posedness of the two-dimensional
Faddeev model under the equivariant hypothesis.


title: Super Yang-Mills Plasma

abstract:
  The N = 4 super Yang-Mills plasma is studied in the regime of weak coupling.
Collective excitations and collisional processes are discussed and compared to
those of QCD plasma. The two systems are concluded to be very similar to each
other with the differences mostly reflecting different numbers of degrees of
freedom.


title: On the 2D Isentropic Euler System with Unbounded Initial vorticity

abstract:
  This paper is devoted to the study of the low Mach number limit for the 2D
isentropic Euler system associated to ill-prepared initial data with slow blow
up rate on $\log\varepsilon^{-1}$. We prove in particular the strong
convergence to the solution of the incompressible Euler system when the
vorticity belongs to some weighted $BMO$ spaces allowing unbounded functions.
The proof is based on the extension of the result of \cite{B-K} to a
compressible transport model.


title: Small intersection numbers in the curve graph

abstract:
  Let $S_{g,p}$ denote the genus $g$ orientable surface with $p \ge 0$
punctures, and let $\omega(g,p)= 3g+p-4$. We prove the existence of infinitely
long geodesic rays $\left\{v_{0},v_{1}, v_{2}, ...\right\}$ in the curve graph
satisfying the following optimal intersection property: for any natural number
$k$, the endpoints $v_{i},v_{i+k}$ of any length $k$ subsegment intersect
$O(\omega^{k-2})$ times. By combining this with work of the first author, we
answer a question of Dan Margalit.


title:
Analysis of periodicity of extinction using the 2012 geological time
  scale

abstract:
  Analysis of two independent data sets with increased taxonomic resolution
(genera rather than families) using the revised 2012 time scale reveals that an
extinction periodicity first detected by Raup and Sepkoski (1984) for only the
post-Paleozoic actually runs through the entire Phanerozoic. Although there is
not a local peak of extinction every 27 million years, an excess of the
fraction of genus extinction by interval follows a 27 million year timing
interval and differs from a random distribution at the p ~ 0.02 level. A 27
million year periodicity in the spectrum of interval lengths no longer appears,
removing the question of a possible artifact arising from it. Using a method
originally developed in Bambach (2006) we identify 19 intervals of marked
extinction intensity, including mass extinctions, spanning the last 470 million
years (and with another six present in the Cambrian) and find that 10 of the 19
lie within 3 Myr of the maxima in the spacing of the 27 Myr periodicity, which
differs from a random distribution at the p = 0.004 level. These 19 intervals
of marked extinction intensity also preferentially occur during decreasing
diversity phases of a well-known 62 Myr periodicity in diversity (16 of 19, p =
0.002). Both periodicities appear to enhance the likelihood of increased
severity of extinction, but the cause of neither periodicity is known.
Variations in the strength of the many suggested causes of extinction coupled
to the variation in combined effect of the two different periodicities as they
shift in and out of phase is surely one of the reasons that definitive
comparative study of the causes of major extinction events is so elusive.

categories: q-bio.PE astro-ph.EP astro-ph.GA physics.data-an physics.geo-ph


title: Calibration of an Articulated Camera System with Scale Factor Estimation

abstract:
  Multiple Camera Systems (MCS) have been widely used in many vision
applications and attracted much attention recently. There are two principle
types of MCS, one is the Rigid Multiple Camera System (RMCS); the other is the
Articulated Camera System (ACS). In a RMCS, the relative poses (relative 3-D
position and orientation) between the cameras are invariant. While, in an ACS,
the cameras are articulated through movable joints, the relative pose between
them may change. Therefore, through calibration of an ACS we want to find not
only the relative poses between the cameras but also the positions of the
joints in the ACS.
  In this paper, we developed calibration algorithms for the ACS using a simple
constraint: the joint is fixed relative to the cameras connected with it during
the transformations of the ACS. When the transformations of the cameras in an
ACS can be estimated relative to the same coordinate system, the positions of
the joints in the ACS can be calculated by solving linear equations. However,
in a non-overlapping view ACS, only the ego-transformations of the cameras and
can be estimated. We proposed a two-steps method to deal with this problem. In
both methods, the ACS is assumed to have performed general transformations in a
static environment. The efficiency and robustness of the proposed methods are
tested by simulation and real experiments. In the real experiment, the
intrinsic and extrinsic parameters of the ACS are obtained simultaneously by
our calibration procedure using the same image sequences, no extra data
capturing step is required. The corresponding trajectory is recovered and
illustrated using the calibration results of the ACS. Since the estimated
translations of different cameras in an ACS may scaled by different scale
factors, a scale factor estimation algorithm is also proposed. To our
knowledge, we are the first to study the calibration of ACS.


title: On a problem by Dol'nikov

abstract:
  In 2011 at an Oberwolfach workshop in Discrete Geometry, V. Dol'nikov posed
the following problem. Consider three non-empty families of translates of a
convex compact set $K$ in the plane. Suppose that every two translates from
different families have a point of intersection. Is it always true that one of
the families can be pierced by a set of three points?
  A result by R. N. Karasev from 2000 gives, in fact, an affirmative answer to
the "monochromatic" version of the problem above. That is, if all the three
families in the problem coincide. In the present paper we solve Dol'nikov's
problem positively if $K$ is either centrally symmetric or a triangle, and show
that the conclusion can be strengthened if $K$ is an euclidean disk. We also
confirm the conjecture if we are given four families satisfying the conditions
above.


title:
An explicit kernel-split panel-based Nystr\"om scheme for integral
  equations on axially symmetric surfaces

abstract:
  A high-order accurate, explicit kernel-split, panel-based, Fourier-Nystr\"om
discretization scheme is developed for integral equations associated with the
Helmholtz equation in axially symmetric domains. Extensive incorporation of
analytic information about singular integral kernels and on-the-fly computation
of nearly singular quadrature rules allow for very high achievable accuracy,
also in the evaluation of fields close to the boundary of the computational
domain.


title: SOSTOOLS Version 4.00 Sum of Squares Optimization Toolbox for MATLAB

abstract:
  The release of SOSTOOLS v4.00 comes as we approach the 20th anniversary of
the original release of SOSTOOLS v1.00 back in April, 2002. SOSTOOLS was
originally envisioned as a flexible tool for parsing and solving polynomial
optimization problems, using the SOS tightening of polynomial positivity
constraints, and capable of adapting to the ever-evolving fauna of applications
of SOS. There are now a variety of SOS programming parsers beyond SOSTOOLS,
including YALMIP, Gloptipoly, SumOfSquares, and others. We hope SOSTOOLS
remains the most intuitive, robust and adaptable toolbox for SOS programming.
Recent progress in Semidefinite programming has opened up new possibilities for
solving large Sum of Squares programming problems, and we hope the next decade
will be one where SOS methods will find wide application in different areas.
  In SOSTOOLS v4.00, we implement a parsing approach that reduces the
computational and memory requirements of the parser below that of the SDP
solver itself. We have re-developed the internal structure of our polynomial
decision variables. Specifically, polynomial and SOS variable declarations made
using sossosvar, sospolyvar, sosmatrixvar, etc now return a new polynomial
structure, dpvar. This new polynomial structure, is documented in the enclosed
dpvar guide, and isolates the scalar SDP decision variables in the SOS program
from the independent variables used to construct the SOS program. As a result,
the complexity of the parser scales almost linearly in the number of decision
variables. As a result of these changes, almost all users will notice a
significant increase in speed, with large-scaleproblems experiencing the most
dramatic speedups. Parsing time is now always less than 10% of time spent in
the SDP solver. Finally, SOSTOOLS now provides support for the MOSEK solver
interface as well as the SeDuMi, SDPT3, CSDP, SDPNAL, SDPNAL+, and SDPA
solvers.


title: The domination number and the least $Q$-eigenvalue

abstract:
  A vertex set $D$ of a graph $G$ is said to be a dominating set if every
vertex of $V(G)\setminus D$ is adjacent to at least a vertex in $D$, and the
domination number $\gamma(G)$ ($\gamma$, for short) is the minimum cardinality
of all dominating sets of $G$. For a graph, the least $Q$-eigenvalue is the
least eigenvalue of its signless Laplacian matrix. In this paper, for a
nonbipartite graph with both order $n$ and domination number $\gamma$, we show
that $n\geq 3\gamma-1$, and show that it contains a unicyclic spanning subgraph
with the same domination number $\gamma$. By investigating the relation between
the domination number and the least $Q$-eigenvalue of a graph, we minimize the
least $Q$-eigenvalue among all the nonbipartite graphs with given domination
number.


title: Potassium under pressure: electronic origin of complex structures

abstract:
  Recent high-pressure x-ray diffraction studies of alkali metals revealed
unusual complex structures that follow the body-centered and face-centered
cubic structures on compression. The structural sequence of potassium under
compression to 1 Megabar is as follows: bcc - fcc - h-g (tI19*), hP4 - oP8 -
tI4 - oC16. We consider configurations of Brillouin-Jones zones and the Fermi
surface within a nearly-free-electron model in order to analyze the importance
of these configurations for the crystal structure energy that contains two main
contributions: electrostatic (Ewald) and electronic (band structure) energies.
The latter can be lowered due to a formation of Brillouin zone planes close to
the Fermi surface opening an energy gap at these planes. Under pressure, the
band structure energy term becomes more important leading to a formation of
complex low-symmetry structures. The stability of the post-fcc phases in K is
attributed to the changes in the valence electron configuration implying the
overlap of valence band with the upper core electrons. This effect offers an
understanding of structural complexity of alkali metals under strong
compression.


title: One-dimensional Bose-Hubbard model with local three-body interactions

abstract:
  We employ the (dynamical) density matrix renormalization group technique to
investigate the ground-state properties of the Bose-Hubbard model with
nearest-neighbor transfer amplitudes t and local two-body and three-body
repulsion of strength U and W, respectively. We determine the phase boundaries
between the Mott-insulating and superfluid phases for the lowest two Mott lobes
from the chemical potentials. We calculate the tips of the Mott lobes from the
Tomonaga-Luttinger liquid parameter and confirm the positions of the
Kosterlitz-Thouless points from the von Neumann entanglement entropy. We find
that physical quantities in the second Mott lobe such as the gap and the
dynamical structure factor scale almost perfectly in t/(U+W), even close to the
Mott transition. Strong-coupling perturbation theory shows that there is no
true scaling but deviations from it are quantitatively small in the
strong-coupling limit. This observation should remain true in higher dimensions
and for not too large attractive three-body interactions.


title: Radiation of the Tunnel Electron on Secondary Center of Recombination

abstract:
  We discuss the photon emission that occurs due to the radiative recombination
of an electron on a nearby center after tunneling ionization. The model of an
active electron is used, and analytical solution to three-dimensional problem
is obtained. The dependence of the photon emission from a distance between
centers of ionization and a recombination, and also the electric field
orientation are investigated. The formulas for probability of recombination
radiation are derived.


title:
Derived equivalent surfaces and abelian varieties, and their zeta
  functions

abstract:
  In this paper, it is demonstrated that derived equivalence between smooth,
projective, connected schemes that are either surfaces or abelian implies
equality of zeta functions.


title: Transformations of Wiener Measure and Orthogonal Expansions

abstract:
  In this paper we study the structure of square integrable functionals
measurable with respect to coalescing stochastic flows. The case of $L^2$ space
generated by the process $\eta(\cdot)=w(\min(\tau,\cdot)),$ where $w$ is a
Brownian motion and $\tau$ is the first moment when $w$ hits the given
continuous function $g$ is considered. We present a new construction of
multiple stochastic integrals with respect to the process $\eta.$ Our approach
is based on the change of measure technique. The analogue of the It\^o-Wiener
expansion for the space $L^2(\eta)$ is constructed.


title:
Reaction-diffusion systems of Maxwell-Stefan type with reversible
  mass-action kinetics

abstract:
  The mass-based Maxwell-Stefan approach to one-phase multicomponent reactive
mixtures is mathematically analyzed. It is shown that the resulting
quasilinear, strongly coupled reaction-diffusion system is locally well-posed
in an $L_p$-setting and generates a local semiflow on its natural state space.
Solutions regularize instantly and become strictly positive if their initial
components are all nonnegative and nontrivial. For a class of reversible
mass-action kinetics, the positive equilibria are identified: these are
precisely the constant chemical equilibria of the system, which may form a
manifold. Here the total free energy of the system is employed which serves as
a Lyapunov function for the system. By the generalized principle of linearized
stability, positive equilibria are proved to be normally stable.


title: Dissipative outer billiards: a case study

abstract:
  We study dissipative polygonal outer billiards, i.e. outer billiards about
convex polygons with a contractive reflection law. We prove that dissipative
outer billiards about any triangle and the square are asymptotically periodic,
i.e. they have finitely many global attracting periodic orbits. A complete
description of the bifurcations of the periodic orbits as the contraction rates
vary is given. For the square billiard, we also show that the asymptotic
periodic behavior is robust under small perturbations of the vertices and the
contraction rates. Finally, we describe some numerical experiments suggesting
that dissipative outer billiards about regular polygon are generically
asymptotically periodic.


title: Role of scattering in virtual source array imaging

abstract:
  We consider imaging in a scattering medium where the illumination goes
through this medium but there is also an auxiliary, passive receiver array that
is near the object to be imaged. Instead of imaging with the source-receiver
array on the far side of the object we image with the data of the passive array
on the near side of the object. The imaging is done with travel time migration
using the cross correlations of the passive array data. We showed in [J.
Garnier and G. Papanicolaou, Inverse Problems {28} (2012), 075002] that if (i)
the source array is infinite, (ii) the scattering medium is modeled by either
an isotropic random medium in the paraxial regime or a randomly layered medium,
and (iii) the medium between the auxiliary array and the object to be imaged is
homogeneous, then imaging with cross correlations completely eliminates the
effects of the random medium. It is as if we imaged with an active array,
instead of a passive one, near the object. The purpose of this paper is to
analyze the resolution of the image when both the source array and the passive
receiver array are finite. We show with a detailed analysis that for isotropic
random media in the paraxial regime, imaging not only is not affected by the
inhomogeneities but the resolution can in fact be enhanced. This is because the
random medium can increase the diversity of the illumination. We also show
analytically that this will not happen in a randomly layered medium, and there
may be some loss of resolution in this case.


title: On the higher virial coefficients of a unitary Fermi gas

abstract:
  Third and higher order quantum virial coefficients require the solution of
the corresponding quantum many-body problem. Nevertheless, in an earlier paper
(Phys. Rev. Lett. 108, 260402 (2012)) we proposed that the higher-order cluster
integrals of a dilute unitary fermionic gas may be approximated in terms of the
two-body cluster, together with an appropriate suppression factor. Although not
exact, this ansatz gave a fair agreement up to fugacity z=6 with the
experimentally obtained equation of state. The objective of the present note is
to give some physical arguments in favor of this ansatz.


title: Regularity stabilization for the powers of graded m-primary ideals

abstract:
  This Note provides first a generalization of the stabilization result of
Eisenbud and Ulrich for the regularity of powers of a m-primary ideal to the
case of ideals that are not generated in a single degree. We then partially
extend our previous results expressing this stabilization degree in term of the
regularity of a specific graded strand of the Rees ring : The natural extension
of the statement holds at least if the stabilization index or the regularity is
greater than the number of variables. In any case a precise comparison is
given.


title:
Spectral and temporal properties of the supergiant fast X-ray transient
  IGR J18483-0311 observed by INTEGRAL

abstract:
  IGR J18483-0311 is a supergiant fast X-ray transient whose compact object is
located in a wide (18.5 d) and eccentric (e~0.4) orbit, which shows sporadic
outbursts that reach X-ray luminosities of ~1e36 erg/s. We investigated the
timing properties of IGR J18483-0311 and studied the spectra during bright
outbursts by fitting physical models based on thermal and bulk Comptonization
processes for accreting compact objects. We analysed archival INTEGRAL data
collected in the period 2003-2010, focusing on the observations with IGR
J18483-0311 in outburst. We searched for pulsations in the INTEGRAL light
curves of each outburst. We took advantage of the broadband observing
capability of INTEGRAL for the spectral analysis. We observed 15 outbursts,
seven of which we report here for the first time. This data analysis almost
doubles the statistics of flares of this binary system detected by INTEGRAL. A
refined timing analysis did not reveal a significant periodicity in the
INTEGRAL observation where a ~21s pulsation was previously detected. Neither
did we find evidence for pulsations in the X-ray light curve of an archival
XMM-Newton observation of IGR J18483-0311. In the light of these results the
nature of the compact object in IGR J18483-0311 is unclear. The broadband X-ray
spectrum of IGR J18483-0311 in outburst is well fitted by a thermal and bulk
Comptonization model of blackbody seed photons by the infalling material in the
accretion column of a neutron star. We also obtained a new measurement of the
orbital period using the Swift/BAT light curve.


title: The rotation rates of massive stars: How slow are the slow ones?

abstract:
  Context: Rotation plays a key role in the life cycles of stars with masses
above 8 Msun. Hence, accurate knowledge of the rotation rates of such massive
stars is critical for understanding their properties and for constraining
models of their evolution. Aims: This paper investigates the reliability of
current methods used to derive projected rotation speeds v sin i from
line-broadening signatures in the photospheric spectra of massive stars,
focusing on stars that are not rapidly rotating. Methods: We use slowly
rotating magnetic O-stars with well-determined rotation periods to test the
Fourier transform (FT) and goodness-of-fit (GOF) methods typically used to
infer projected rotation rates of massive stars. Results: For our two magnetic
test stars with measured rotation periods longer than one year, i.e., with v
sin i < 1 km/s, we derive v sin i ~ 40-50 km/s from both the FT and GOF
methods. These severe overestimates are most likely caused by an insufficient
treatment of the competing broadening mechanisms referred to as microturbulence
and macroturbulence. Conclusions: These findings warn us not to rely
uncritically on results from current standard techniques to derive projected
rotation speeds of massive stars in the presence of significant additional line
broadening, at least when v sin i <~ 50 km/s. This may, for example, be crucial
for i) determining the statistical distribution of observed rotation rates of
massive stars, ii) interpreting the evolutionary status and spin-down histories
of rotationally braked B-supergiants, and iii) explaining the deficiency of
observed O-stars with spectroscopically inferred v sin i ~ 0 km/s. Further
investigations of potential shortcomings of the above techniques are presently
under way.


title:
Starshaped locally convex hypersurfaces with prescribed curvature and
  boundary

abstract:
  In this paper we find strictly locally convex hypersurfaces in
$\mathbb{R}^{n+1}$ with prescribed curvature and boundary. The main result is
that if the given data admits a strictly locally convex radial graph as a
subsolution, we can find a radial graph realizing the prescribed curvature and
boundary. As an application we show any smooth domain on the boundary of a
compact strictly convex body can be deformed to a smooth hypersurface with the
same boundary (inside the convex body) and realizing any prescribed curvature
function smaller than the curvature of the body.


title:
Ground and bound state solutions of semilinear time-harmonic Maxwell
  equations in a bounded domain

abstract:
  We find solutions $E:\Omega\to\mathbb{R}^3$ of the problem \[
\left\{\begin{aligned} &\nabla\times(\nabla\times E) + \lambda E = \partial_E
F(x,E) &&\quad \text{in}\Omega\\ &\nu\times E = 0 &&\quad
\text{on}\partial\Omega \end{aligned} \right. \] on a simply connected, smooth,
bounded domain $\Omega\subset\mathbb{R}^3$ with connected boundary and exterior
normal $\nu:\partial\Omega\to\mathbb{R}^3$. Here $\nabla\times$ denotes the
curl operator in $\mathbb{R}^3$, the nonlinearity
$F:\Omega\times\mathbb{R}^3\to\mathbb{R}$ is superquadratic and subcritical in
$E$. The model nonlinearity is of the form $F(x,E)=\Gamma(x)|E|^p$ for
$\Gamma\in L^\infty(\Omega)$ positive, some $2<p<6$. It need not be radial nor
even in the $E$-variable. The problem comes from the time-harmonic Maxwell
equations, the boundary conditions are those for $\Omega$ surrounded by a
perfect conductor.


title:
Exponential tail behaviour of self-similar solutions to Smoluchowski's
  coagulation equation

abstract:
  We consider self-similar solutions with finite mass to Smoluchowski's
coagulation equation for rate kernels that have homogeneity zero but are
possibly singular such as Smoluchowski's original kernel. We prove pointwise
exponential decay of these solutions under rather mild assumptions on the
kernel. If the support of the kernel is sufficiently large around the diagonal
we also proof that $\lim_{x \to \infty} \frac{1}{x} \log
\Big(\frac{1}{f(x)}\Big)$ exists. In addition we prove properties of the
prefactor if the kernel is uniformly bounded below.


title: Heralded generation of Bell states using atomic ensembles

abstract:
  We propose a scheme that utilizes the collective enhancement of a photonic
mode inside an atomic ensemble together with a proper Zeeman manifold in order
to achieve a heralded polarization entangled Bell state. The entanglement is
between two photons that are separated in time and can be used as a post
selected deterministic source for applications such as quantum repeaters where
a subsequent entanglement swapping measurement is employed. We present a
detailed analysis of the practical limitation of the scheme.


title:
On Robustness Analysis of Stochastic Biochemical Systems by
  Probabilistic Model Checking

abstract:
  This report proposes a novel framework for a rigorous robustness analysis of
stochastic biochemical systems. The technique is based on probabilistic model
checking. We adapt the general definition of robustness introduced by Kitano to
the class of stochastic systems modelled as continuous time Markov Chains in
order to extensively analyse and compare robustness of biological models with
uncertain parameters. The framework utilises novel computational methods that
enable to effectively evaluate the robustness of models with respect to
quantitative temporal properties and parameters such as reaction rate constants
and initial conditions.
  The framework is applied to gene regulation as an example of a central
biological mechanism where intrinsic and extrinsic stochasticity plays crucial
role due to low numbers of DNA and RNA molecules. Using our methods we have
obtained a comprehensive and precise analysis of stochastic dynamics under
parameter uncertainty. Furthermore, we apply our framework to compare several
variants of two-component signalling networks from the perspective of
robustness with respect to intrinsic noise caused by low populations of
signalling components. We succeeded to extend previous studies performed on
deterministic models (ODE) and show that stochasticity may significantly affect
obtained predictions. Our case studies demonstrate that the framework can
provide deeper insight into the role of key parameters in maintaining the
system functionality and thus it significantly contributes to formal methods in
computational systems biology.


title: The Leavitt path algebras of generalized Cayley graphs

abstract:
  Let $n$ be a positive integer. For each $0\leq j \leq n-1$ we let $C_n^{j}$
denote Cayley graph for the cyclic group ${\mathbb Z}_n $ with respect to the
subset $\{1, j\}$. For any such pair $(n,j)$ we compute the size of the
Grothendieck group of the Leavitt path algebra $L_K(C_n^j)$; the analysis is
related to a collection of integer sequences described by Haselgrove in the
1940's. When $j=0,1,$ or 2, we are able to extract enough additional
information about the structure of these Grothendieck groups so that we may
apply a Kirchberg-Phillips-type result to explicitly realize the algebras
$L_K(C_n^j)$ as the Leavitt path algebras of graphs having at most three
vertices. The analysis in the $j=2$ case leads us to some perhaps surprising
and apparently nontrivial connections to the classical Fibonacci sequence.


title:
Group approximation in Cayley topology and coarse geometry, Part I:
  Coarse embeddings of amenable groups

abstract:
  The objective of this series is to study metric geometric properties of
(coarse) disjoint unions of amenable Cayley graphs. We employ the Cayley
topology and observe connections between large scale structure of metric spaces
and group properties of Cayley accumulation points. In this Part I, we prove
that a disjoint union has property A of G. Yu if and only if all groups
appearing as Cayley accumulation points in the space of marked groups are
amenable. As an application, we construct two disjoint unions of finite special
linear groups (and unimodular linear groups) with respect to two systems of
generators that look similar such that one has property A and the other does
not admit (fibred) coarse embeddings into any Banach space with non-trivial
type (for instance, any uniformly convex Banach space).


title: Sphere equivalence, Banach expanders, and extrapolation

abstract:
  We study the Banach spectral gap lambda_1(G;X,p) of finite graphs G for pairs
(X,p) of Banach spaces and exponents. We define the notion of sphere
equivalence between Banach spaces and show a generalization of Matousek's
extrapolation for Banach spaces sphere equivalent to uniformly convex ones. As
a byproduct, we prove that expanders are automatically expanders with respects
to (X,p) for any X sphere equivalent to a uniformly curved Banach space and for
any p strictly bigger than 1.


title:
Controlling the surface plasmon excitation efficiency using dielectric
  magneto-optical cavity

abstract:
  The diffraction of a plane wave by a magneto-optical cavity located on a
metal interface is investigated theoretically. We show that the excitation of
localized eigenmodes of the cavity allows one to efficiently excite the surface
plasmon polariton (SPP). We exploit the polarization and symmetry properties of
the cavity modes to propose an efficient approach for controlling the SPP
intensity through an external magnetic field. The presented theoretical
predictions are in good agreement with the rigorous computations based on the
generalized Lorentz reciprocity theorem and aperiodic Fourier modal method. The
magnetization-induced relative intensity variation of the excited SPP
demonstrated in numerical computations varies from a few percent to 100%
depending on the polarization of the incident wave. Such large modulation opens
new possibilities for efficient SPP modulation with considered magneto-optical
intensity effect.


title: Was ist Unendlichkeit - und wenn ja, wie viele?

abstract:
  This article, written in German language, gives a very elementary
introduction to infinite sets. It is meant for interested non-mathematicians.


title:
Measurement of CP violation in the phase space of $B^{\pm} \rightarrow
  K^{+} K^{-} \pi^{\pm}$ and $B^{\pm} \rightarrow \pi^{+} \pi^{-} \pi^{\pm}$
  decays

abstract:
  The charmless decays $B^{\pm} \rightarrow K^{+}K^{-}\pi^{\pm}$ and $B^{\pm}
\rightarrow \pi^{+}\pi^{-}\pi^{\pm}$ are reconstructed in a data set,
corresponding to an integrated luminosity of 1.0 fb$^{-1}$ of pp collisions at
a center-of-mass energy of 7 TeV, collected by LHCb in 2011. The inclusive
charge asymmetries of these modes are measured to be $A_{CP}(B^{\pm}
\rightarrow K^{+}K^{-}\pi^{\pm}) =-0.141 \pm 0.040 (stat) \pm 0.018 (syst) \pm
0.007 (J/\psi K^{\pm})$ and $A_{CP}(B^{\pm} \rightarrow
\pi^{+}\pi^{-}\pi^{\pm}) = 0.117 \pm 0.021 (stat) \pm 0.009 (syst) \pm 0.007
(J/\psi K^{\pm})$, where the third uncertainty is due to the CP asymmetry of
the $B^{\pm} \rightarrow J/\psi K^{\pm}$ reference mode. In addition to the
inclusive CP asymmetries, larger asymmetries are observed in localized regions
of phase space.


title:
The groups of automorphisms of the Lie algebras of polynomial vector
  fields with zero or constant divergence

abstract:
  The group of automorphisms is found for the Lie algebra of polynomial vector
fields with constant divergence.


title:
Bimetal-and-electret-based thermal energy harvesters - Application to a
  battery-free Wireless Sensor Node

abstract:
  This paper introduces a thermal energy harvester turning thermal gradients
into electricity by coupling a bimetallic strip to an electret-based converter:
the bimetallic strip behaves as a thermal-to-mechanical power converter turning
thermal gradients into mechanical oscillations that are finally converted into
electricity with the electret. Output powers of 5.4uW were reached on a hot
source at 70{\deg}C, and, contrary to the previous proofs of concept, the new
devices presented in this paper do not require forced convection to work,
making them compatible with standard conditions of thermal energy harvesting
and environments such as hot pipes, pumps and more generally industrial
equipment. Finally, ten energy harvesters have been parallelized and combined
to a self-starting power management circuit made of a flyback converter to
supply a battery-free Wireless Temperature Sensor Node, sending information
every 100 seconds after its startup state.


title: Avoiding 2-binomial squares and cubes

abstract:
  Two finite words $u,v$ are 2-binomially equivalent if, for all words $x$ of
length at most 2, the number of occurrences of $x$ as a (scattered) subword of
$u$ is equal to the number of occurrences of $x$ in $v$. This notion is a
refinement of the usual abelian equivalence. A 2-binomial square is a word $uv$
where $u$ and $v$ are 2-binomially equivalent.
  In this paper, considering pure morphic words, we prove that 2-binomial
squares (resp. cubes) are avoidable over a 3-letter (resp. 2-letter) alphabet.
The sizes of the alphabets are optimal.


title: Massless Wigner particles in conformal field theory are free

abstract:
  We show that in a four dimensional conformal Haag-Kastler net, its massless
particle spectrum is generated by a free field subnet. If the massless particle
spectrum is scalar, then the free field subnet decouples as a tensor product
component.


title:
Instability of pre-existing resonances under a small constant electric
  field

abstract:
  Two simple model operators are considered which have pre-existing resonances.
A potential corresponding to a small electric field, $f$, is then introduced
and the resonances of the resulting operator are considered as $f\to0$. It is
shown that these resonances are not continuous in this limit. It is conjectured
that a similar behavior will appear in more complicated models of atoms and
molecules. Numerical results are presented.


title:
The Solar Neighborhood XXXI: Discovery of an Unusual Red+White Dwarf
  Binary at ~25 Parsecs via Astrometry and UV Imaging

abstract:
  We report the discovery of a nearby M5.0V dwarf at 24.6 pc, SCR 1848-6855,
that is orbited by an unusual companion causing an astrometric perturbation of
more than 200 milli-arcseconds. This is by far the largest perturbation found
to date among more than 700 targets observed during our long-term
astrometry/photometry program at the CTIO 0.9-m telescope. We present here a
suite of astrometric, photometric, and spectroscopic observations of this high
proper motion (~1.3"/yr) system in an effort to reveal the nature of this
unusual binary. The measured near-UV and optical U band fluxes exceed those
expected for comparable M5.0V stars, and excess flux is also detected in the
spectral range 4000A--7000A. The elusive companion has been detected in
HST-STIS+MAMA images at 1820A and 2700A, and our analysis shows that it is
probably a rare, cool, white dwarf with T = 4600-5500K. Given the long-term
astrometric coverage, the prospects for an accurate mass determination are
excellent, although as yet we can only provide limits on the unusual
companion's mass.


title: A Plasma {\beta} Transition Within a Propagating Flux Rope

abstract:
  We present a 2.5D MHD simulation of a magnetic flux rope (FR) propagating in
the heliosphere and investigate the cause of the observed sharp plasma beta
transition. Specifically, we consider a strong internal magnetic field and an
explosive fast start, such that the plasma beta is significantly lower in the
FR than the sheath region that is formed ahead. This leads to an unusual FR
morphology in the first stage of propagation, while the more traditional view
(e.g. from space weather simulations like Enlil) of a `pancake' shaped FR is
observed as it approaches 1 AU. We investigate how an equipartition line,
defined by a magnetic Weber number, surrounding a core region of a propagating
FR can demarcate a boundary layer where there is a sharp transition in the
plasma beta. The substructure affects the distribution of toroidal flux, with
the majority of the flux remaining in a small core region which maintains a
quasi-cylindrical structure. Quantitatively, we investigate a locus of points
where the kinetic energy density of the relative inflow field is equal to the
energy density of the transverse magnetic field (i.e. effective tension force).
The simulation provides compelling evidence that at all heliocentric distances
the distribution of toroidal magnetic flux away from the FR axis is not linear;
with 80% of the toroidal flux occurring within 40% of the distance from the FR
axis. Thus our simulation displays evidence that the competing ideas of a
pancaking structure observed remotely can coexist with a quasi-cylindrical
magnetic structure seen in situ.


title: Red giants seismology

abstract:
  The space-borne missions CoRoT and Kepler are indiscreet. With their
asteroseismic programs, they tell us what is hidden deep inside the stars.
Waves excited just below the stellar surface travel throughout the stellar
interior and unveil many secrets: how old is the star, how big, how massive,
how fast (or slow) its core is dancing. This paper intends to \emph{paparazze}
the red giants according to the seismic pictures we have from their interiors.


title:
Search for Neutron Flux Generation in a Plasma Discharge Electrolytic
  Cell

abstract:
  Following some recent unexpected hints of neutron production in setups like
high-voltage atmospheric discharges and plasma discharges in electrolytic
cells, we present a measurement of the neutron flux in a configuration similar
to the latter. We use two different types of neutron detectors,
poly-allyl-diglicol-carbonate (PADC, aka CR-39) tracers and Indium disks. At
95% C.L. we provide an upper limit of 1.5 neutrons cm^-2 s^-1 for the thermal
neutron flux at ~5 cm from the center of the cell. Allowing for a higher energy
neutron component the largest allowed flux is 64 neutrons cm^-2 s^-1. This
upper limit is two orders of magnitude smaller than what previously claimed in
an electrolytic cell plasma discharge experiment. Furthermore the behavior of
the CR-39 is discussed to point our possible sources of spurious signals.

categories: physics.ins-det hep-ex nucl-ex physics.plasm-ph


title: Photonic Cavity Synchronization of Nanomechanical Oscillators

abstract:
  Synchronization in oscillatory systems is a frequent natural phenomenon and
is becoming an important concept in modern physics. Nanomechanical resonators
are ideal systems for studying synchronization due to their controllable
oscillation properties and engineerable nonlinearities. Here we demonstrate
synchronization of two nanomechanical oscillators via a photonic resonator,
enabling optomechanical synchronization between mechanically isolated
nanomechanical resonators. Optical backaction gives rise to both reactive and
dissipative coupling of the mechanical resonators, leading to coherent
oscillation and mutual locking of resonators with dynamics beyond the widely
accepted phase oscillator (Kuramoto) model. Besides the phase difference
between the oscillators, also their amplitudes are coupled, resulting in the
emergence of sidebands around the synchronized carrier signal.


title:
Beauty is more attractive: Particle Production and Moduli trapping with
  Higher Dimensional Interaction

abstract:
  We study quantum effects on moduli dynamics arising from particle production
near the enhanced symmetry point (ESP). We focus on non-renormalizable
couplings between the moduli field and the field that becomes light at the ESP.
Considering higher dimensional interaction, we find that particle production is
significant in a large area, which is even larger than the area that is
expected from a renormalizable interaction. It is possible to find this
possibility from a trivial adiabatic condition; however the quantitative
estimation of particle production and trapping of the field in motion are far
from trivial. In this paper we study particle production and trapping in
detail, using both the analytical and numerical calculations, to find a clear
and intuitive result that supports trapping in a vast variety of theories. Our
study shows that trapping driven by a non-renormalizable interaction is
possible. This possibility has not been considered in previous works. Some
phenomenological models of particle physics will be mentioned to complement
discussion.


title: Sounding stellar cores with mixed modes

abstract:
  The space-borne missions CoRoT and Kepler have opened a new era in stellar
physics, especially for evolved stars, with precise asteroseismic measurements
that help determine precise stellar parameters and perform ensemble astero
seismology. This paper deals with the quality of the information that we can
retrieve from the oscillations. It focusses on the conditions for obtaining the
most accurate measurement of the radial and non-radial oscillation patterns.
This accuracy is a prerequisite for making the best with asteroseismic data.
From radial modes, we derive proxies of the stellar mass and radii with an
unprecedented accuracy for field stars. For dozens of subgiants and thousands
of red giants, the identification of mixed modes (corresponding to gravity
waves propagating in the core coupled to pressure waves propagating in the
envelope) indicates unambiguously their evolutionary status. As probes of the
stellar core, these mixed modes also reveal the internal differential rotation
and show the spinning down of the core rotation of stars ascending the red
giant branch. A toy model of the coupling of waves constructing mixed modes is
exposed, for illustrating many of their features.


title: Society Functions Best with an Intermediate Level of Creativity

abstract:
  In a society, a proportion of the individuals can benefit from creativity
without being creative themselves by copying the creators. This paper uses an
agent-based model of cultural evolution to investigate how society is affected
by different levels of individual creativity. We performed a time series
analysis of the mean fitness of ideas across the artificial society varying
both the percentage of creators, C, and how creative they are, p using two
discounting methods. Both analyses revealed a valley in the adaptive landscape,
indicating a tradeoff between C and p. The results suggest that excess
creativity at the individual level can be detrimental at the level of the
society because creators invest in unproven ideas at the expense of propagating
proven ideas.


title:
Propagation and perfect transmission in three-waveguide axially varying
  couplers

abstract:
  We study a class of three-waveguide axially varying structures whose dynamics
are described by the su(3) algebra. Their analytic propagator can be found
based on the corresponding Lie group generators. In particular, we show that
the field propagator corresponding to three-waveguide structures that have
arbitrarily varying coupling coefficients and identical refractive indices is
associated with the orbital angular momentum algebra. The conditions necessary
to achieve perfect transmission from the first to the last waveguide element
are obtained and particular cases are elucidated analytically.


title: Higher Structures: gerbes and Nijenhuis forms

abstract:
  In the first chapter, we give a precise and general description of gerbes
valued in arbitrary crossed module and over an arbitrary differential stack. We
do it using only Lie groupoids, hence ordinary differential geometry, by
considering differential stacks as being Lie groupoids up to Morita
equivalence. We prove the coincidence with the existing notions by comparing
our construction with non-Abelian cohomology. More precisely, we introduce the
key notion of extension of Lie groupoids valued in a crossed-module. We relate
it with Dedecker's non-Abelian 1-cocycles, and we then show that Morita
equivalence amounts to co-boundaries, paving the way for a general definition
of gerbes valued in a crossed-module over a differential stack. In the second
chapter, we develop the theory of Nijenhuis forms on L-infinity-algebras.
First, we recall a convenient notion of Richardson-Nijenhuis bracket on the
graded symmetric vector valued forms on a graded vector space, bracket for
which L-infinity-algebras are simply Poisson elements. Weak Nijenhuis vector
valued forms for a given L-infinity-algebra are defined to be forms of degree 0
deforming (i.e. taking bracket) that Poisson element into an other Poisson
element. Nijenhuis forms are those forms N for which deforming twice by N is
like deforming once by a form K called the square of N. We obtain in this
context an infnite hierarchy of L-infinity-algebras. classifcation of Nijenhuis
forms on anchor-free Lie 2-algebras can be completed. We also show that there
is, under adequate conditions, a one to one correspondence between the
Nijenhuis vector valued forms N with respect to the Lie 2-algebra associated to
a Courant algebroid and Nijenhuis C-infinity-linear maps on the Courant
algebroid itself. We give examples of Nijenhuis vector valued forms on the Lie
n-algebras associated to n-plectic manifolds.


title: Effectiveness of pre- and inprocessing for CDCL-based SAT solving

abstract:
  Applying pre- and inprocessing techniques to simplify CNF formulas both
before and during search can considerably improve the performance of modern SAT
solvers. These algorithms mostly aim at reducing the number of clauses,
literals, and variables in the formula. However, to be worthwhile, it is
necessary that their additional runtime does not exceed the runtime saved
during the subsequent SAT solver execution. In this paper we investigate the
efficiency and the practicability of selected simplification algorithms for
CDCL-based SAT solving. We first analyze them by means of their expected impact
on the CNF formula and SAT solving at all. While testing them on real-world and
combinatorial SAT instances, we show which techniques and combinations of them
yield a desirable speedup and which ones should be avoided.


title: Quantum quenches, linear response and superfluidity out of equilibrium

abstract:
  By analysing the sensitivity to a twist in the boundary conditions of the
stationary state attained by a many-body system long after a quantum quench, we
extend the concepts of the helicity modulus and the stiffness to
non-equilibrium situations. Using these generalised quantities, we characterise
the out-of-equilibrium dynamics of hard-core bosons quenched to/from
superfluid/insulating phases and show that qualitative new features emerge as
compared to the equilibrium case. Our predictions can be tested in experiments
with cold bosonic atoms confined in toroidal traps and subject to artificial
gauge fields.


title: The RMS Survey: Galactic distribution of massive star formation

abstract:
  Abridged: We have used the well-selected sample of ~1750 embedded, young,
massive stars identified by the RMS survey to investigate the Galactic
distribution of recent massive star formation. We describe the various methods
used to assign distances extracted from the literature, and solve the distance
ambiguities towards ~200 sources located within the Solar circle using archival
HI data. These distances are used to calculate bolometric luminosities and
estimate the survey completeness (~2x10^4 lsun). In total, we calculate the
distance and luminosity of ~1650 sources, one third of which are above the
survey's completeness threshold. Examination of the sample's longitude,
latitude, radial velocities and mid-infrared images has identified ~120 small
groups of sources, many of which are associated with well known star formation
complexes, such as W43, W49 and W51.
  We compare the positional distribution of the sample with the expected
locations of the spiral arms, assuming a model of the Galaxy consisting of four
gaseous arms. The distribution of young massive stars in the Milky Way is
spatially correlated with the spiral arms, with strong peaks in the source
position and luminosity distributions at the arms' Galactocentric radii. The
overall source and luminosity surface densities are both well correlated with
the surface density of the molecular gas, which suggests that the massive star
formation rate per unit molecular mass is approximately constant across the
Galaxy.
  We estimate the total luminosity of the embedded massive star population to
be ~0.76x10^8 lsun, 30% of which is associated with the ten most active star
forming complexes. We measure the scale height as a function of Galactocentric
distance and find that it increases only modestly from ~20-30 pc between 4 and
8 kpc, but much more rapidly at larger distances.


title:
Fine-grained Categorization -- Short Summary of our Entry for the
  ImageNet Challenge 2012

abstract:
  In this paper, we tackle the problem of visual categorization of dog breeds,
which is a surprisingly challenging task due to simultaneously present low
interclass distances and high intra-class variances. Our approach combines
several techniques well known in our community but often not utilized for
fine-grained recognition:
  (1) automatic segmentation, (2) efficient part detection, and (3) combination
of multiple features. In particular, we demonstrate that a simple head detector
embedded in an off-the-shelf recognition pipeline can improve recognition
accuracy quite significantly, highlighting the importance of part features for
fine-grained recognition tasks. Using our approach, we achieved a 24.59% mean
average precision performance on the Stanford dog dataset.


title:
$L^2$ well posed Cauchy Problems and Symmetrizability of First Order
  Systems

abstract:
  The Cauchy problem for first order system $L(t, x, \D_t, \D_x)$ is known to
be well posed in $L^2$ when a it admits a microlocal symmetrizer $S(t,x, \xi)$
which is smooth in $\xi$ and Lipschitz continuous in $(t, x)$. This paper
contains three main results. First we show that a Lipsshitz smoothness globally
in $(t,x, \xi)$ is sufficient. Second, we show that the existence of
symmetrizers with a given smoothness is equivalent to the existence of
\emph{full symmetrizers} having the same smoothness. This notion was first
introduced in \cite{FriLa1}. This is the key point to prove the third result
that the existence of microlocal symmetrizer is preserved if one changes the
direction of time, implying local uniqueness and finite speed of propagation.


title:
Towards Energy Neutrality in Energy Harvesting Wireless Sensor Networks:
  A Case for Distributed Compressive Sensing?

abstract:
  This paper advocates the use of the emerging distributed compressive sensing
(DCS) paradigm in order to deploy energy harvesting (EH) wireless sensor
networks (WSN) with practical network lifetime and data gathering rates that
are substantially higher than the state-of-the-art. In particular, we argue
that there are two fundamental mechanisms in an EH WSN: i) the energy diversity
associated with the EH process that entails that the harvested energy can vary
from sensor node to sensor node, and ii) the sensing diversity associated with
the DCS process that entails that the energy consumption can also vary across
the sensor nodes without compromising data recovery. We also argue that such
mechanisms offer the means to match closely the energy demand to the energy
supply in order to unlock the possibility for energy-neutral WSNs that leverage
EH capability. A number of analytic and simulation results are presented in
order to illustrate the potential of the approach.


title:
Robertson-Schroedinger type formulation of Ozawa's noise-disturbance
  uncertainty principle

abstract:
  In this work we derive a matrix formulation of a noise-disturbance
uncertainty relation, which is akin to the Robertson-Schr\"odinger uncertainty
principle. Our inequality is stronger than Ozawa's uncertainty principle and
takes noise-disturbance correlations into account. Moreover, we show that, for
certain types of measurement interactions, it is covariant with respect to
linear symplectic transformations of the noise and disturbance operators.


title:
Analytic continuation of holonomy germs of Riccati foliations along
  Brownian paths

abstract:
  This paper deals with the question of analytic continuation of holonomy germs
of holomorphic foliations. We prove that for a quasi-minimal Riccati foliation
of the complex projective plane, any holonomy germ of the foliation between
complex projective lines can be analytically continued along a generic Brownian
path.


title:
Quenched invariance principle for simple random walk on clusters in
  correlated percolation models

abstract:
  We prove quenched invariance principle for simple random walk on the unique
infinite percolation cluster for a general class of percolation models on Z^d,
d>=2, with long-range correlations introduced in arXiv:1212.2885, solving one
of the open problems from there. This gives new results for random
interlacements in dimension d>=3 at every level, as well as for the vacant set
of random interlacements and the level sets of the Gaussian free field in the
regime of the so-called local uniqueness (which is believed to coincide with
the whole supercritical regime). An essential ingredient of our proof is a new
isoperimetric inequality for correlated percolation models.


title: Measurements of Absolute Abundances in Solar Flares

abstract:
  We present measurements of elemental abundances in solar flares with the EUV
Variability Experiment (EVE) on the Solar Dynamics Observatory (SDO). EVE
observes both high temperature Fe emission lines (Fe XV-Fe XXIV) and continuum
emission from thermal bremsstrahlung that is proportional to the abundance of
H. By comparing the relative intensities of line and continuum emission it is
possible to determine the enrichment of the flare plasma relative to the
composition of the photosphere. This is the first ionization potential or FIP
bias ($f$). Since thermal bremsstrahlung at EUV wavelengths is relatively
insensitive to the electron temperature, it is important to account for the
distribution of electron temperatures in the emitting plasma. We accomplish
this by using the observed spectra to infer the differential emission measure
distribution and FIP bias simultaneously. In each of the 21 flares that we
analyze we find that the observed composition is close to photospheric. The
mean FIP bias in our sample is $f=1.27\pm0.23$. This analysis suggests that the
bulk of the plasma evaporated during a flare comes from deep in the
chromosphere, below the region where elemental fractionation occurs.


title: Time dependent mean-field games in the subquadratic case

abstract:
  In this paper we consider time-dependent mean-field games with subquadratic
Hamiltonians and power-like local dependence on the measure. We establish
existence of classical solutions under a certain set of conditions depending on
both the growth of the Hamiltonian and the dimension. This is done by combining
regularity estimates for the Hamilton-Jacobi equation based on the
Gagliardo-Nirenberg interpolation inequality with polynomial estimates for the
Fokker-Planck equation. This technique improves substantially the previous
results on the regularity of time-dependent mean-field games.


title:
Pairing of valence electrons as necessary condition for energy
  minimization in a crystal

abstract:
  Pairing of valence electrons can lead to energy minimization of a crystal. It
can be proved by use of representation of the valence electrons as plane waves
in periodic potential of the crystal.


title: Properties of metrics and infinite geometric graphs

abstract:
  We consider isomorphism properties of infinite random geometric graphs
defined over a variety of metrics. In previous work, it was shown that for
$\mathbb{R}^n$ with the $L_{\infty}$-metric, the infinite random geometric
graph is, with probability 1, unique up to isomorphism. However, in the case
$n=2$ this is false with either of the $L_2$-metric. We generalize this result
to a large family of metrics induced by norms. Within this class of metric
spaces, we show that the infinite geometric graph is not unique up to
isomorphism if it has the new property which we name truncating: each
step-isometry from a dense set to itself is an isometry. As a corollary, we
derive that the infinite random geometric graph defined in $L_p$ space is not
unique up to isomorphism with probability 1 for all finite $p>1.$


title:
Numerical Modeling of Nanoparticles Transport with Two-Phase Flow in
  Porous Media Using Iterative Implicit Method

abstract:
  In this paper, we introduce a mathematical model to describe the
nanoparticles transport carried by a two-phase flow in a porous medium
including gravity, capillary forces and Brownian diffusion. Nonlinear iterative
IMPES scheme is used to solve the flow equation, and saturation and pressure
are calculated at the current iteration step and then the transport equation is
soved implicitly. Therefore, once the nanoparticles concentration is computed,
the two equations of volume of the nanoparticles available on the pore surfaces
and the volume of the nanoparticles entrapped in pore throats are solved
implicitly. The porosity and the permeability variations are updated at each
time step after each iteration loop. Two numerical examples, namely, regular
heterogeneous permeability and random permeability are considered. We monitor
the changing of the fluid and solid properties due to adding the nanoparticles.
Variation of water saturation, water pressure, nanoparticles concentration and
porosity are presented graphically.


title: A No-Scale Framework for Sub-Planckian Physics

abstract:
  We propose a minimal model framework for physics below the Planck scale with
the following features: (i) it is based on no-scale supergravity, as favoured
in many string compactifications, (ii) it incorporates Starobinsky-like
inflation, and hence is compatible with constraints from the Planck satellite,
(iii) the inflaton may be identified with a singlet field in a see-saw model
for neutrino masses, providing an efficient scenario for reheating and
leptogenesis, (iv) supersymmetry breaking occurs with an arbitrary scale and a
cosmological constant that vanishes before radiative corrections, (v) regions
of the model parameter space are compatible with all LHC, Higgs and dark matter
constraints.


title: Astrophysical black holes may radiate, but they do not evaporate

abstract:
  This paper argues that the effect of Hawking radiation on an astrophysical
black hole situated in a realistic cosmological context is not total
evaporation of the black hole; rather there will always be a remnant mass. The
key point is that the locus of emission of Hawking radiation is not the
globally defined event horizon. Rather the emission domain lies just outside a
timelike Marginal Outer Trapped Surface that is locally defined. The emission
domain is mainly located inside the event horizon. A spacelike singularity
forms behind the event horizon, and most of the Hawking radiation ends up at
this singularity rather than at infinity. Whether any Hawking radiation reaches
infinity depends on the relation between the emission domain and the event
horizon. From the outside view, even if radiation is seen as always being
emitted, the black hole never evaporates away, rather its mass and entropy
asymptote to finite non-zero limits, and the event horizon always acts as a
sink for matter and information. From an inside view, the matter and
information disappear into the singularity, which is the boundary of spacetime.
The argument is based on the nature of the processes at work plus a careful
delineation of the relevant causal domains; in order to confirm this model and
determine details of the outcome, detailed calculations of the expectation
value of the stress-energy-momentum tensor are needed to determine back
reaction effects.


title: Multisymplectic variational integrators and space/time symplecticity

abstract:
  Multisymplectic variational integrators are structure preserving numerical
schemes especially designed for PDEs derived from covariant spacetime Hamilton
principles. The goal of this paper is to study the properties of the temporal
and spatial discrete evolution maps obtained from a multisymplectic numerical
scheme. Our study focuses on a 1+1 dimensional spacetime discretized by
triangles, but our approach carries over naturally to more general cases. In
the case of Lie group symmetries, we explore the links between the discrete
Noether theorems associated to the multisymplectic spacetime discretization and
to the temporal and spatial discrete evolution maps, and emphasize the role of
boundary conditions. We also consider in detail the case of multisymplectic
integrators on Lie groups. Our results are illustrated with the numerical
example of a geometrically exact beam model.


title:
Tunable Quantum Phase Transitions in a Resonant Level Coupled to Two
  Dissipative Baths

abstract:
  We study tunneling through a resonant level connected to two dissipative
bosonic baths: one is the resistive environment of the source and drain leads,
while the second comes from coupling to potential fluctuations on a resistive
gate. We show that several quantum phase transitions (QPT) occur in such a
model, transitions which emulate those found in interacting systems such as
Luttinger liquids or Kondo systems. We first use bosonization to map this
dissipative resonant level model to a resonant level in a Luttinger liquid, one
with, curiously, two interaction parameters. Drawing on methods for analyzing
Luttinger liquids at both weak and strong coupling, we obtain the phase
diagram. For strong dissipation, a Berezinsky-Kosterlitz-Thouless QPT separates
strong-coupling and weak-coupling (charge localized) phases. In the
source-drain symmetric case, all relevant backscattering processes disappear at
strong coupling, leading to perfect transmission at zero temperature. In fact,
a QPT occurs as a function of the coupling asymmetry or energy of the resonant
level: the two phases are (i) the system is cut into two disconnected pieces
(zero transmission), or (ii) the system is a single connected piece with
perfect transmission, except for a disconnected fractional degree of freedom.
The latter arises from the competition between the two fermionic leads (source
and drain), as in the two-channel Kondo effect.


title: IntelligentWeb Agent for Search Engines

abstract:
  In this paper we review studies of the growth of the Internet and
technologies that are useful for information search and retrieval on the Web.
Search engines are retrieve the efficient information. We collected data on the
Internet from several different sources, e.g., current as well as projected
number of users, hosts, and Web sites. The trends cited by the sources are
consistent and point to exponential growth in the past and in the coming
decade. Hence it is not surprising that about 85% of Internet users surveyed
claim using search engines and search services to find specific information and
users are not satisfied with the performance of the current generation of
search engines; the slow retrieval speed, communication delays, and poor
quality of retrieved results. Web agents, programs acting autonomously on some
task, are already present in the form of spiders, crawler, and robots. Agents
offer substantial benefits and hazards, and because of this, their development
must involve attention to technical details. This paper illustrates the
different types of agents,crawlers, robots,etc for mining the contents of web
in a methodical, automated manner, also discusses the use of crawler to gather
specific types of information from Web pages, such as harvesting e-mail
addresses


title:
A non self-adjoint model on a two dimensional noncommutative space with
  unbound metric

abstract:
  We demonstrate that a non self-adjoint Hamiltonian of harmonic oscillator
type defined on a two-dimensional noncommutative space can be diagonalized
exactly by making use of pseudo-bosonic operators. The model admits an
antilinear symmetry and is of the type studied in the context of PT-symmetric
quantum mechanics. Its eigenvalues are computed to be real for the entire range
of the coupling constants and the biorthogonal sets of eigenstates for the
Hamiltonian and its adjoint are explicitly constructed. We show that despite
the fact that these sets are complete and biorthogonal, they involve an
unbounded metric operator and therefore do not constitute (Riesz) bases for the
Hilbert space $\Lc^2(\Bbb R^2)$, but instead only D-quasi bases. As recently
proved by one of us (FB), this is sufficient to deduce several interesting
consequences.


title: SUSY dark matter(s)

abstract:
  We review here the status of different dark matter candidates in the context
of supersymmetric models, in particular the neutralino as a realization of the
WIMP-mechanism and the gravitino. We give a summary of the recent bounds in
direct and indirect detection and also of the LHC searches relevant for the
dark matter question. We discuss also the implications of the Higgs discovery
for the supersymmetric dark matter models and give the prospects for the future
years.


title:
Content-Specific Broadcast Cellular Networks based on User Demand
  Prediction: A Revenue Perspective

abstract:
  The Long Term Evolution (LTE) broadcast is a promising solution to cope with
exponentially increasing user traffic by broadcasting common user requests over
the same frequency channels. In this paper, we propose a novel network
framework provisioning broadcast and unicast services simultaneously. For each
serving file to users, a cellular base station determines either to broadcast
or unicast the file based on user demand prediction examining the file's
content specific characteristics such as: file size, delay tolerance, price
sensitivity. In a network operator's revenue maximization perspective while not
inflicting any user payoff degradation, we jointly optimize resource
allocation, pricing, and file scheduling. In accordance with the state of the
art LTE specifications, the proposed network demonstrates up to 32% increase in
revenue for a single cell and more than a 7-fold increase for a 7 cell
coordinated LTE broadcast network, compared to the conventional unicast
cellular networks.


title: Logarithmic two-Point Correlation Functions from a z = 2 Lifshitz Model

abstract:
  The Einstein-Proca action is known to have asymptotically locally Lifshitz
spacetimes as classical solutions. For dynamical exponent z=2, two-point
correlation functions for fluctuations around such a geometry are derived
analytically. It is found that the retarded correlators are stable in the sense
that all quasinormal modes are situated in the lower half-plane of complex
frequencies. Correlators in the longitudinal channel exhibit features that are
reminiscent of a structure usually obtained in field theories that are
logarithmic, i.e. contain an indecomposable highest weight representation. This
suggests the model at hand as a candidate for a gravity dual of a logarithmic
field theory with anisotropic scaling symmetry.


title:
Thermodynamic Bethe ansatz for non-equilibrium steady states: exact
  energy current and fluctuations in integrable QFT

abstract:
  We evaluate the exact energy current and scaled cumulant generating function
(related to the large-deviation function) in non-equilibrium steady states with
energy flow, in any integrable model of relativistic quantum field theory
(IQFT) with diagonal scattering. Our derivations are based on various recent
results of D. Bernard and B. Doyon. The steady states are built by connecting
homogeneously two infinite halves of the system thermalized at different
temperatures $T_l$, $T_r$, and waiting for a long time. We evaluate the current
$J(T_l,T_r)$ using the exact QFT density matrix describing these
non-equilibrium steady states and using Al.B. Zamolodchikov's method of the
thermodynamic Bethe ansatz (TBA). The scaled cumulant generating function is
obtained from the extended fluctuation relations which hold in integrable
models. We verify our formula in particular by showing that the conformal field
theory (CFT) result is obtained in the high-temperature limit. We analyze
numerically our non-equilibrium steady-state TBA equations for three models:
the sinh-Gordon model, the roaming trajectories model, and the sine-Gordon
model at a particular reflectionless point. Based on the numerics, we
conjecture that an infinite family of non-equilibrium $c$-functions, associated
to the scaled cumulants, can be defined, which we interpret physically. We
study the full scaled distribution function and find that it can be described
by a set of independent Poisson processes. Finally, we show that the
"additivity" property of the current, which is known to hold in CFT and was
proposed to hold more generally, does not hold in general IQFT, that is
$J(T_l,T_r)$ is not of the form $f(T_l)-f(T_r)$.


title: Effective Quotation: relating approaches to language-integrated query

abstract:
  Language-integrated query techniques have been explored in a number of
different language designs. We consider two different, type-safe approaches
employed by Links and F#. Both approaches provide rich dynamic query generation
capabilities, and thus amount to a form of heterogeneous staged computation,
but to date there has been no formal investigation of their relative
expressiveness. We present two core calculi Eff and Quot, respectively
capturing the essential aspects of language-integrated querying using effects
in Links and quotation in LINQ. We show via translations from Eff to Quot and
back that the two approaches are equivalent in expressiveness. Based on the
translation from Eff to Quot, we extend a simple Links compiler to handle
queries.


title: Phase field methods for binary recovery

abstract:
  We consider the inverse problem of recovering a binary function from blurred
and noisy data. Such problems arise in many applications, for example image
processing and optimal control of PDEs. Our formulation is based on the
Mumford-Shah model, but with a phase field approximation to the perimeter
regularisation. We use a double obstacle potential as well as a smooth double
well potential. We introduce an iterative method for solving the problem,
develop a suitable discretisation of this iterative method, and prove some
convergence results. Numerical simulations are presented which illustrate the
usefulness of the approach and the relative merits of the phase field models.


title: Injectivity of Keller Mappings

abstract:
  It is proved that for a Jacobi pair $(F,G)\in C[x,y]^2$, the Keller mapping:
$(a,b)\mapsto(F(a,b),G(a,b))$ for $(a,b)\in C^2$, is injective. In particular,
the $2$-dimensional Jacobi conjecture holds.


title:
Asymptotic properties of maximum likelihood estimators for Heston models
  based on continuous time observations

abstract:
  We study asymptotic properties of maximum likelihood estimators for Heston
models based on continuous time observations of the log-price process. We
distinguish three cases: subcritical (also called ergodic), critical and
supercritical. In the subcritical case, asymptotic normality is proved for all
the parameters, while in the critical and supercritical cases, non-standard
asymptotic behavior is described.