title:
Search for a habitable terrestrial planet transiting the nearby red
  dwarf GJ 1214

abstract:
  High-precision eclipse spectrophotometry of transiting terrestrial exoplanets
represents a promising path for the first atmospheric characterizations of
habitable worlds and the search for life outside our solar system. The
detection of terrestrial planets transiting nearby late-type M-dwarfs could
make this approach applicable within the next decade, with soon-to-come general
facilities. In this context, we previously identified GJ 1214 as a
high-priority target for a transit search, as the transit probability of a
habitable planet orbiting this nearby M4.5 dwarf would be significantly
enhanced by the transiting nature of GJ 1214 b, the super-Earth already known
to orbit the star. Based on this observation, we have set up an ambitious
high-precision photometric monitoring of GJ 1214 with the Spitzer Space
Telescope to probe the inner part of its habitable zone in search of a
transiting planet as small as Mars. We present here the results of this transit
search. Unfortunately, we did not detect any other transiting planets. Assuming
that GJ 1214 hosts a habitable planet larger than Mars that has an orbital
period smaller than 20.9 days, our global analysis of the whole Spitzer dataset
leads to an a posteriori no-transit probability of ~ 98%. Our analysis allows
us to significantly improve the characterization of GJ 1214 b, to measure its
occultation depth to be 70+-35 ppm at 4.5 microns, and to constrain it to be
smaller than 205ppm (3-sigma upper limit) at 3.6 microns. In agreement with the
many transmission measurements published so far for GJ 1214 b, these emission
measurements are consistent with both a metal-rich and a cloudy hydrogen-rich
atmosphere.


title:
Water Electrolysis and Energy Harvesting with 0D Ion-Sensitive
  Field-Effect Transistors

abstract:
  The relationship of the gas bubble size to the size distribution critically
influences the effectiveness of electrochemical processes. Several optical and
acoustical techniques have been used to characterize the size and emission
frequency of bubbles. Here, we used zero-dimensional (0D) ion-sensitive
field-effect transistors (ISFETs) buried under a microbath to detect the
emission of individual bubbles electrically and to generate statistics on the
bubble emission time. The bubble size was evaluated via a simple model of the
electrolytic current. We suggest that energy lost during water electrolysis
could be used to generate electric pulses at an optimal efficiency with an
array of 0D ISFETs.


title:
Dissipation vs. quadratic nonlinearity: from a priori energy bound to
  higher-order regularizing effect

abstract:
  We consider a rather general class of evolutionary PDEs involving dissipation
(of possibly fractional order), which competes with quadratic nonlinearities on
the regularity of the overall equation. This includes as prototype models,
Burgers' equation, the Navier-Stokes equations, the surface quasi-geostrophic
equations and the Keller-Segel model for chemotaxis. Here we establish a
Petrowsky type parabolic estimate of such equations which entail a precise time
decay of higher-order Sobolev norms for this class of equations. To this end,
we introduce as a main new tool, an "infinite order energy functional", E(t): =
\Sigma_n \alpha_n t^n |(-\Delta)^{n\theta/2} u(*,t)|_{H^{\beta_c}} for
appropriate critical regularity index \beta_c. It captures the regularizing
effect of all higher order derivatives of u(*,t), by proving --- for a
carefully, problem-dependent choice of weights {\alpha_n}, that E(t) is
non-increasing in time.


title: Confinement and quantum anomaly in quasi-1D spinless fermion chains

abstract:
  We consider the field renormalization group (RG) of two coupled one-spatial
dimension (1D) spinless fermion chains under intraforward, interforward,
interbackscattering and interumklapp interactions until two-loops order. Up to
this order, we demonstrate the quantum confinement in the RG flow, where the
interband chiral Fermi points reduce to single chiral Fermi points and the
renormalized interaction couplings have Luttinger liquid fixed points. We show
that this quasi-1D system is equivalently described in terms of one and
two-color interactions and address the problem of quantum anomaly, inherent to
this system, as a direct consequence of coupling 1+1 free Dirac fields to one
and two-color interactions.


title:
Information content versus word length in natural language: A reply to
  Ferrer-i-Cancho and Moscoso del Prado Martin [arXiv:1209.1751]

abstract:
  Recently, Ferrer i Cancho and Moscoso del Prado Martin [arXiv:1209.1751]
argued that an observed linear relationship between word length and average
surprisal (Piantadosi, Tily, & Gibson, 2011) is not evidence for communicative
efficiency in human language. We discuss several shortcomings of their approach
and critique: their model critically rests on inaccurate assumptions, is
incapable of explaining key surprisal patterns in language, and is incompatible
with recent behavioral results. More generally, we argue that statistical
models must not critically rely on assumptions that are incompatible with the
real system under study.


title: Quantum Tunneling of Stock Price in Range Bound Market Conditions

abstract:
  Applications of Quantum Tunneling effect have long gone beyond the
traditional physical meaning. Initially created by Gamow to explain
{\alpha}-decay of nuclear particles, along the time, quantum tunneling found
fertile domain of research in chemistry and recently in biology, where the new
discipline of Quantum Biology emerges. The present paper extends the
applicability of quantum tunneling to financial markets. In a recent paper [1]
a time-independent equation for pricing the options having the underlying stock
in a range bound markets is found. The equation is identical with a
time-independent Schrodinger equation but incorporates elements of finance. The
financial time-independent equation for option pricing is solved to explain a
particular explosive violent movement of stock price in range bound markets.
The aforementioned particular stock price movement is assimilated with a
quantum tunneling effect. The probability of stock price to quantum tunneling
out of the bounded region, known as transmission coefficient, is deduced.
Quantum aspects of tunneling effect in financial markets are discussed. Recent
evidences of price quantum tunneling in stock market are also shown.


title: Influence of pions on the hadron-quark phase transition

abstract:
  In this work we present the features of the hadron-quark phase transition
diagrams in which the pions are included in the system. To construct such
diagrams we use two different models in the description of the hadronic and
quark sectors. At the quark level, we consider two distinct parametrizations of
the Polyakov-Nambu-Jona-Lasinio (PNJL) models. In the hadronic side, we use a
well known relativistic mean-field (RMF) nonlinear Walecka model. We show that
the effect of the pions on the hadron-quark phase diagrams is to move the
critical end point (CEP) of the transitions lines. Such an effect also depends
on the value of the critical temperature (T_0) in the pure gauge sector used to
parametrize the PNJL models. Here we treat the phase transitions using two
values for T_0, namely, T_0 = 270 MeV and T_0 = 190 MeV. The last value is used
to reproduce lattice QCD data for the transition temperature at zero chemical
potential.


title:
Speed of adaptation and genomic footprints of host-parasite coevolution
  under arms race and trench warfare dynamics

abstract:
  Coevolution is expected to follow two alternative dynamics, often called
trench warfare and arms races in plant-pathogen systems. Trench warfare
situations are stable cycles of allele frequencies at the coevolving loci of
both host and parasite, and it is predicted that the loci will show molecular
evolutionary signatures of balancing selection, while arms races involve
successive selective sweeps at the interacting loci. We study a haploid
gene-for-gene model that includes mutation and genetic drift due to finite
population size. We study the outcomes under different coevolutionary
parameters to quantify the frequency of fixation of alleles, i.e. occurrence of
an arms race dynamics. We find that contrary to the conventional wisdom, trench
warfare situations do not imply larger numbers of coevolutionary cycles per
unit time than arms races. Therefore, one cannot infer the nature of the
dynamics in such systems based on the speed of coevolution estimated from cycle
times. We subsequently perform coalescent simulations to generate sequences at
the host and parasite loci. We ask whether the signatures expected under
balancing selection or selective sweeps (unexpectedly high or low diversity,
and high or low Tajima D values, respectively) are likely to be observable in
genomic data. Genomic footprints of recurrent selective sweeps are often found,
whereas trench warfare yields signatures of balancing selection only in
parasite sequences, and only in a limited parameter space with high effective
population sizes and long-term selection. Therefore, the existence of a
deterministic polymorphic equilibrium does not imply long-term trench warfare
necessary for the signature of balancing selection to be observed in the
coevolving genes sequence. Our results suggest that to search for signatures of
coevolution via population genomics, it is best to study pathogen rather than
host genomes.


title:
Stable regular critical points of the Mumford-Shah functional are local
  minimizers

abstract:
  In this paper it is shown that any regular critical point of the Mumford-Shah
functional, with positive definite second variation, is an isolated local
minimizer with respect to competitors which are sufficiently close in the
L^1-topology.


title:
Evolution of the tangent vectors and localization of the stable and
  unstable manifolds of hyperbolic orbits by Fast Lyapunov Indicators

abstract:
  The Fast Lyapunov Indicators are functions defined on the tangent fiber of
the phase-space of a discrete (or continuous) dynamical system, by using a
finite number of iterations of the dynamics. In the last decade, they have been
largely used in numerical computations to localize the resonances in the
phase-space and, more recently, also the stable and unstable manifolds of
normally hyperbolic invariant manifolds. In this paper, we provide an analytic
description of the growth of tangent vectors for orbits with initial conditions
which are close to the stable-unstable manifolds of a hyperbolic saddle point
of an area-preserving map. The representation explains why the Fast Lyapunov
Indicator detects the stable-unstable manifolds of all fixed points which
satisfy a certain condition. If the condition is not satisfied, a suitably
modified Fast Lyapunov Indicator can be still used to detect the
stable-unstable manifolds. The new method allows for a detection of the
manifolds with a number of precision digits which increases linearly with
respect to the integration time. We illustrate the method on the critical
problem of detection of the so-called tube manifolds of the Lyapunov orbits of
L1,L2 in the circular restricted three-body problem.


title: Compton scattering of blackbody photons by relativistic electrons

abstract:
  We present simple and accurate analytical formulae for the rates of Compton
scattering by relativistic electrons integrated over the energy distribution of
blackbody seed photons. Both anisotropic scattering, in which blackbody photons
arriving from one direction are scattered by an anisotropic electron
distribution into another direction, and scattering of isotropic seed photons
are considered. Compton scattering by relativistic electrons off blackbody
photons from either stars or CMB takes place, in particular, in microquasars,
colliding-wind binaries, supernova remnants, interstellar medium, and the
vicinity of the Sun.


title: On the consistency of MPS

abstract:
  The consistency of Moving Particle Semi-implicit (MPS) method in reproducing
the gradient, divergence and Laplacian differential operators is discussed in
the present paper. Its relation to the Smoothed Particle Hydrodynamics (SPH)
method is rigorously established. The application of the MPS method to solve
the Navier-Stokes equations using a fractional step approach is treated,
unveiling inconsistency problems when solving the Poisson equation for the
pressure. A new corrected MPS method incorporating boundary terms is proposed.
Applications to one dimensional boundary value Dirichlet and mixed
Neumann-Dirichlet problems and to two-dimensional free-surface flows are
presented.


title: Precise shaping of laser light by an acousto-optic deflector

abstract:
  We present a laser beam shaping method using acousto-optic deflection of
light and discuss its application to dipole trapping of ultracold atoms. By
driving the acousto-optic deflector with multiple frequencies, we generate an
array of overlapping diffraction-limited beams that combine to form an
arbitrary-shaped smooth and continuous trapping potential. Confinement of atoms
in a flat-bottomed potential formed by a laser beam with uniform intensity over
its central region confers numerous advantages over the harmonic confinement
intrinsic to Gaussian beam dipole traps and many other trapping schemes.We
demonstrate the versatility of this beam shaping method by generating
potentials with large flat-topped regions as well as intensity patterns
compensating for residual external potentials to create a uniform background to
which the trapping potential of experimental interest can be added.


title:
Surfaces with one constant principal curvature in three-dimensional
  space forms

abstract:
  We study surfaces with one constant principal curvature in Riemannian and
Lorentzian three-dimensional space forms. Away from umbilic points they are
characterized as one-parameter foliations by curves of constant curvature, each
of these curves being centered at a point of a regular curve and contained in
its normal plane. In some cases, a kind of trichotomy phenomenon is observed:
the curves of the foliations may be circles, hyperbolas or horocycles,
depending of whether the constant principal curvature is respectively larger,
smaller of equal to one (not necessarily in this order). We describe explicitly
some examples showing that there do exist complete surfaces with one constant
principal curvature enjoying both umbilic and non-umbilic points.


title:
Low-Resolution Spectrum of the Diffuse Galactic Light and 3.3 um PAH
  emission with AKARI InfraRed Camera

abstract:
  We first obtained the spectrum of the diffuse Galactic light (DGL) at general
interstellar space in 1.8-5.3 um wavelength region with the low-resolution
prism spectroscopy mode of the AKARI Infra-Red Camera (IRC) NIR channel. The
3.3 um PAH band is detected in the DGL spectrum at Galactic latitude |b| < 15
deg, and its correlations with the Galactic dust and gas are confirmed. The
correlation between the 3.3 um PAH band and the thermal emission from the
Galactic dust is expressed not by a simple linear correlation but by a relation
with extinction. Using this correlation, the spectral shape of DGL at optically
thin region (5 deg < |b| < 15 deg) was derived as a template spectrum. Assuming
that the spectral shape of this template spectrum is uniform at any position,
DGL spectrum can be estimated by scaling this template spectrum using the
correlation between the 3.3 um PAH band and the thermal emission from the
Galactic dust.


title:
Reentrant Superconductivity and Superconducting Critical Temperature
  Oscillations in F/S/F trilayers of Cu41Ni59/Nb/Cu41Ni59 Grown on Cobalt Oxide

abstract:
  Ferromagnet/Superconductor/Ferromagnet (F/S/F) trilayers constitute the core
of a superconducting spin valve. The switching effect of the spin valve is
based on interference phenomena occurring due to the proximity effect at the
S/F interfaces. A remarkable effect is only expected if the core structure
exhibits strong critical temperature oscillations, or most favorable, reentrant
superconductivity, when the thickness of the ferromagnetic layer is increased.
The core structure has to be grown on an antiferromagnetic oxide layer (or such
layer to be placed on top) to pin by exchange bias the
magnetization-orientation of one of the ferromagnetic layers. In the present
paper we demonstrate that this is possible, keeping the superconducting
behavior of the core structure undisturbed.


title: Efficient quantum protocols for XOR functions

abstract:
  We show that for any Boolean function f on {0,1}^n, the bounded-error quantum
communication complexity of XOR functions $f\circ \oplus$ satisfies that
$Q_\epsilon(f\circ \oplus) = O(2^d (\log\|\hat f\|_{1,\epsilon} + \log
\frac{n}{\epsilon}) \log(1/\epsilon))$, where d is the F2-degree of f, and
$\|\hat f\|_{1,\epsilon} = \min_{g:\|f-g\|_\infty \leq \epsilon} \|\hat f\|_1$.
This implies that the previous lower bound $Q_\epsilon(f\circ \oplus) =
\Omega(\log\|\hat f\|_{1,\epsilon})$ by Lee and Shraibman \cite{LS09} is tight
for f with low F2-degree. The result also confirms the quantum version of the
Log-rank Conjecture for low-degree XOR functions. In addition, we show that the
exact quantum communication complexity satisfies $Q_E(f) = O(2^d \log \|\hat
f\|_0)$, where $\|\hat f\|_0$ is the number of nonzero Fourier coefficients of
f. This matches the previous lower bound $Q_E(f(x,y)) = \Omega(\log rank(M_f))$
by Buhrman and de Wolf \cite{BdW01} for low-degree XOR functions.


title: Resummation of fluctuations near ferromagnetic quantum critical points

abstract:
  We present a detailed analysis of the non-analytic structure of the free
energy for the itinerant ferromagnet near the quantum critical point in two and
three dimensions. We analyze a model of electrons with an isotropic dispersion
interacting through a contact repulsion. A fermionic version of the quantum
order-by-disorder mechanism allows us to calculate the free energy as a
functional of the dispersion in the presence of homogeneous and spiralling
magnetic order. We re-sum the leading divergent contributions, to derive an
algebraic expression for the non-analytic contribution to free energy from
quantum fluctuations. Using a recursion which relates sub-leading divergences
to the leading term, we calculate the full T=0 contribution in $d=3$. We
propose an interpolating functional form, which allows us to track phase
transition lines at temperatures far below the tricritical point and down to
T=0. In $d=2$, quantum fluctuations are stronger and non-analyticities more
severe. Using a similar re-summation approach, we find that despite the
different non-analytic structures, the phase diagrams in two and three
dimensions are remarkably similar, exhibiting an incommensurate spiral phase
near to the avoided quantum critical point.


title:
Low-Resolution Spectrum of the Extragalactic Background Light with AKARI
  InfraRed Camera

abstract:
  The Extragalactic Background Light (EBL) as an integrated light from outside
of our Galaxy includes information of the early universe and the Dark Ages. We
analyzed the spectral data of the astrophysical diffuse emission obtained with
the low-resolution spectroscopy mode on the AKARI Infra-Red Camera (IRC) in
1.8-5.3 um wavelength region. Although the previous EBL observation in this
wavelength region is restricted to the observations by DIRBE and IRTS, this
study adds a new independent result with negligible contamination of Galactic
stars owing to higher sensitivity for point sources. Other two major foreground
components, the zodiacal light (ZL) and the diffuse Galactic light (DGL), were
subtracted by taking correlations with ZL brightness estimated by the DIRBE ZL
model and with the 100 um dust thermal emission, respectively. The isotropic
emission was obtained as EBL, which shows significant excess over integrated
light of galaxies at <4 um. The obtained EBL is consistent with the previous
measurements by IRTS and DIRBE.


title:
On eigenfunction expansions of first-order symmetric systems and
  ordinary differential operators of an odd order

abstract:
  We study general (not necessarily Hamiltonian) first-order symmetric systems
$J y'-B(t)y=\D(t) f(t)$ on an interval $\cI=[a,b\rangle $ with the regular
endpoint $a$. It is assumed that the deficiency indices $n_\pm(\Tmi)$ of the
minimal relation $\Tmi$ satisfy $n_+(\Tmi)< n_-(\Tmi)$. We define
  $\l$-depending boundary conditions which are analogs of separated
self-adjoint boundary conditions for Hamiltonian systems. With a boundary value
problem involving such conditions we associate an exit space self-adjoint
extension $\wt T$ of $\Tmi$ and the $m$-function $m(\cd)$, which is an analog
of the Titchmarsh-Weyl coefficient for the Hamiltonian system. By using
$m$-function we obtain the eigenfunction expansion with the spectral function
$\Si(\cd)$ of the minimally possible dimension and characterize the case when
spectrum of $\wt T$ is defined by $\Si(\cd)$. Moreover, we parametrize all
spectral functions in terms of a Nevanlinna type boundary parameter.
Application of these results to ordinary differential operators of an odd order
enables us to complete the results by Everitt and Krishna Kumar on the
Titchmarsh-Weyl theory of such operators.


title:
Memory Effect and Triplet Pairing Generation in the Superconducting
  Exchange Biased Co/CoOx/Cu41Ni59/Nb/Cu41Ni59 Layered Heterostructure

abstract:
  We fabricated a nanolayered hybrid superconductor-ferromagnet spin-valve
structure, the resistive state of which depends on the preceding magnetic field
polarity. The effect is based on a strong exchange bias (about -2 kOe) on a
diluted ferromagnetic copper-nickel alloy and generation of a long range odd in
frequency triplet pairing component. The difference of high and low resistance
states at zero magnetic field is 90% of the normal state resistance for a
transport current of 250 {\mu}A and still around 42% for 10 {\mu}A. Both logic
states of the structure do not require biasing fields or currents in the idle
mode.


title:
Random attractors for stochastic evolution equations driven by
  fractional Brownian motion

abstract:
  The main goal of this article is to prove the existence of a random attractor
for a stochastic evolution equation driven by a fractional Brownian motion with
$H\in (1/2,1)$. We would like to emphasize that we do not use the usual
cohomology method, consisting of transforming the stochastic equation into a
random one, but we deal directly with the stochastic equation. In particular,
in order to get adequate a priori estimates of the solution needed for the
existence of an absorbing ball, we will introduce stopping times to control the
size of the noise. In a first part of this article we shall obtain the
existence of a pullback attractor for the non-autonomous dynamical system
generated by the pathwise mild solution of an nonlinear infinite-dimensional
evolution equation with non--trivial H\"older continuous driving function. In a
second part, we shall consider the random setup: stochastic equations having as
driving process a fractional Brownian motion with $H\in (1/2,1)$. Under a
smallness condition for that noise we will show the existence and uniqueness of
a random attractor for the stochastic evolution equation.


title:
New Spin Squeezing and Other Entanglement Tests for Two Mode Systems of
  Identical Bosons

abstract:
  For any quantum state representing a physical system of identical particles,
the density operator must satisfy the symmetrisation principle (SP) and for
massive particles also conform to super-selection rules (SSR) that prohibit
coherences between differing total particle numbers. Here we consider
bi-partitite states for systems of massive bosons, where both the system and
subsystems are modes (or sets of modes), particles being associated with
differing mode occupancies. To define non-entangled or separable states the
subsystem density operators are also required to satisfy the SP and conform to
SSR, in contrast to some other approaches. Whilst in the presence of these
additional constraints some of the known entanglement criteria are still valid,
we present a detailed treatment to establish the validity of known criteria and
derive new ones.


title:
Magnetic and Kohn-Luttinger instabilities near a Van Hove singularity:
  monolayer versus twisted bilayer graphene

abstract:
  We investigate the many-body instabilities of electrons interacting near Van
Hove singularities arising in monolayer and twisted bilayer graphene. We show
that a pairing instability must be dominant over the tendency to magnetic order
as the Fermi level is tuned to the Van Hove singularity in the conduction band
of graphene. As a result of the extended character of the saddle points in the
dispersion, we find that the pairing of the electrons takes place
preferentially in a channel of f-wave symmetry, with an order parameter
vanishing at the position of the saddle points along the Fermi line. In the
case of the twisted bilayers, the dispersion has instead its symmetry reduced
down to the C_{3v} group and, most importantly, it leads to susceptibilities
that diverge at the saddle points but are integrable along the Fermi line. This
implies that a ferromagnetic instability becomes dominant in the twisted
graphene bilayers near the Van Hove singularity, with a strength which is
amplified as the lowest subband of the electron system becomes flatter for
decreasing twist angle.


title:
Topological Aspects of Charge-Carrier Transmission across Grain
  Boundaries in Graphene

abstract:
  We systematically investigate the transmission of charge carriers across the
grain-boundary defects in polycrystalline graphene by means of the
Landauer-B\"uttiker formalism within the tight-binding approximation.
Calculations reveal a strong suppression of transmission at low energies upon
decreasing the density of dislocations with the smallest Burger's vector
${\mathbf b}=(1,0)$. The observed transport anomaly is explained from the point
of view of back-scattering due to localized states of topological origin. These
states are related to the gauge field associated with all dislocations
characterized by ${\mathbf b}=(n,m)$ with $n-m \neq 3q$ ($q \in \mathbb{Z}$).
Our work identifies an important source of charge-carrier scattering caused by
topological defects present in large-area graphene samples produced by chemical
vapor deposition.


title:
CONE-DHT: A distributed self-stabilizing algorithm for a heterogeneous
  storage system

abstract:
  We consider the problem of managing a dynamic heterogeneous storage system in
a distributed way so that the amount of data assigned to a host in that system
is related to its capacity. Two central problems have to be solved for this:
(1) organizing the hosts in an overlay network with low degree and diameter so
that one can efficiently check the correct distribution of the data and route
between any two hosts, and (2) distributing the data among the hosts so that
the distribution respects the capacities of the hosts and can easily be adapted
as the set of hosts or their capacities change. We present distributed
protocols for these problems that are self-stabilizing and that do not need any
global knowledge about the system such as the number of nodes or the overall
capacity of the system. Prior to this work no solution was known satisfying
these properties.


title:
ISIS: a new N-body cosmological code with scalar fields based on RAMSES.
  Code presentation and application to the shapes of clusters

abstract:
  Several extensions of the standard cosmological model include scalar fields
as new degrees of freedom in the underlying gravitational theory. A particular
class of these scalar field theories include screening mechanisms intended to
hide the scalar field below observational limits in the solar system, but not
on galactic scales, where data still gives freedom to find possible signatures
of their presence. In order to make predictions to compare with observations
coming from galactic and clusters scales (i.e. in the non-linear regime of
cosmological evolution), cosmological N-body simulations are needed, for which
codes that can solve for the scalar field must be developed. We present a new
implementation of scalar-tensor theories of gravity which include screening
mechanisms. The code is based in the already existing code RAMSES, to which we
have added a non-linear multigrid solver that can treat a large class of scalar
tensor theories of modified gravity. We present details of the implementation
and the tests that we made to it. As application of the new code, we have
studied the influence that two particular modified gravity theories, the
symmetron and $f(R)$ gravity, have on the shape of cluster sized dark matter
halos and found consistent results with previous estimations made with a static
analysis.


title:
A population model with non-neutral mutations using branching processes
  with immigration

abstract:
  We consider a stationary continuous model of random size population with
non-neutral mutations using a continuous state branching process with
non-homogeneous immigration. We assume the type (or mutation) of the immigrants
is random given by a constant mutation rate measure. We determine some
genealogical properties of this process such as: distribution of the time to
the most recent common ancestor (MRCA), bottleneck effect at the time to the
MRCA (which might be drastic for some mutation rate measures), favorable type
for the MRCA, asymptotics of the number of ancestors.


title: The conjugacy problem in extensions of Thompson's group F

abstract:
  We solve the twisted conjugacy problem on Thompson's group F. We also exhibit
orbit undecidable subgroups of Aut(F), and give a proof that Aut(F) and
Aut_+(F) are orbit decidable provided a certain conjecture on Thompson's group
T is true. By using general criteria introduced by Bogopolski, Martino and
Ventura in [5], we construct a family of free extensions of F where the
conjugacy problem is unsolvable. As a byproduct of our techniques, we give a
new proof of a result of Bleak-Fel'shtyn-Goncalves in [4] showing that F has
property R_\infty, and which can be extended to show that Thompson's group T
also has property R_\infty.


title: Higgs Boson Creation in Laser-Boosted Lepton Collisions

abstract:
  Electroweak processes in high-energy lepton collisions are considered in a
situation where the incident center-of-mass energy lies below the reaction
threshold, but is boosted to the required level by subsequent laser
acceleration. Within the framework of laser-dressed quantum field theory, we
study the laser-boosted process $\ell^+ \ell^- \to HZ^0$ in detail and specify
the technical demands needed for its experimental realization. Further, we
outline possible qualitative differences to field-free processes regarding the
detection of the produced Higgs bosons.


title: On the q-analogue of Laplace transform

abstract:
  In this paper, we consider a q-analogue of Laplace transform and we
investigate some properties of q-Laplace transform. From our investigation, we
derive some interesting formulae related to q-Laplace transform.


title:
Chemical Diffusion at Mixed Ionic Electronic Semiconductor Interfaces
  and comparison with La2NiO4+d epitaxial thin films

abstract:
  A simple model to describe Mixed Ionic Electronic Conductors (MIEC) in terms
of standard semiconductor physics is described. This model allows to understand
defect equilibrium and charge transport at ideal heterojunctions between
materials simultaneously conducting electronic and ionic point defects and to
explore how rectifying effects on the electronic or ionic currents may affect
the chemical diffusion and voltage at the interfaces under polarization. We
found qualitatively good agreement with experimental measurements of the
electrical conductivity relaxation of La2NiO4+d thin films epitaxially grown on
NdGaO3 (110) substrates when the possible oxygen exchange between film and
substrate is taken into account. We discuss the implications of this model to
understand space charge layer formation and chemical diffusion on oxide thin
film heterostructures when exposed to high temperatures and different oxygen
partial pressures.


title: On nonlinear absolutely summing maps

abstract:
  It is shown that the ultimate version of the nonlinear Pietsch Domination
Theorem remains true, even in a stronger presentation, if one of its hypotheses
is removed. More precisely, we show that no trace of (sub)-homogeneity
assumption is needed. Some consequences are also presented.


title: Explosive synchronization in weighted complex networks

abstract:
  The emergence of dynamical abrupt transitions in the macroscopic state of a
system is currently a subject of the utmost interest. Given a set of phase
oscillators networking with a generic wiring of connections and displaying a
generic frequency distribution, we show how combining dynamical local
information on frequency mismatches and global information on the graph
topology suggests a judicious and yet practical weighting procedure which is
able to induce and enhance explosive, irreversible, transitions to
synchronization. We report extensive numerical and analytical evidence of the
validity and scalability of such a procedure for different initial frequency
distributions, for both homogeneous and heterogeneous networks, as well as for
both linear and non linear weighting functions. We furthermore report on the
possibility of parametrically controlling the width and extent of the
hysteretic region of coexistence of the unsynchronized and synchronized states.


title: The properties of sendograph metric on fuzzy number spaces

abstract:
  This paper discusses the variation of sendograph distances under some algebra
operations.


title:
MEM imaging of multi-wavelength VLBA polarisation observations of Active
  Galactic Nuclei

abstract:
  We have developed a C++ implementation of the Maximum Entropy Method (MEM)
suitable for deconvolving VLBI polarisation data. The first results of this
implementation are presented and compared with CLEAN-based deconvolutions of
the same data. We present Faraday rotation measure and intrinsic polarisation
maps of AGN which have been made from MEM deconvolutions of multi-wavelength
observations of Stokes parameters I, Q and U. The advantages of using MEM are
demonstrated, in particular its enhanced resolution over the CLEAN algorithm.


title: Effects of upward-going cosmic muons on density radiography of volcanoes

abstract:
  Muon tomography aims at deriving the density structure of geological bodies
from their screening attenuation produced on the natural cosmic muons flux.
Because of their open-sky exposure, muons telescopes are subject to noise
fluxes with large intensities relative to the tiny flux of interest. A
recognized source of noise flux comes from fake tracks caused by particles that
fortuitously trigger the telescope detectors at the same time. Such a flux may
be reduced by using multiple-detector telescopes so that fortuitous events
become very unlikely. In the present study, we report on a different type of
noise flux caused by upward-going muons crossing the detectors from the rear
side. We describe field experiments on La Soufri\'ere of Guadeloupe and Mount
Etna, and give details on the high-resolution clocking system and the
statistical procedure necessary to detect upward-going muons. We analyse
several data sets acquired either in calibration or in volcano tomography
situation. All data sets are shown clearly biased by upward-going noise flux
whose intensity may amount to 50% of the measured total flux in given
directions. Biases produced on density radiographies by this kind of flux are
quantified and correction procedures are detailed. Examples for La Soufri\'ere
and Mount Etna are given.


title: Describing the Uncertainties in VLBI Images

abstract:
  We are investigating a new approach to modelling uncertainties in individual
pixels of Very Long Baseline Interferometry (VLBI) intensity (Stokes I, Q, U)
images. Comparison of distributions of our calculated uncertainties for model
sources with the results of Monte Carlo simulations shows that our method
correctly reproduces the overall level and pattern of uncertainties in
intensity images for model sources that are not too compact. Refinement of the
approach to better reproduce uncertainties in compact sources is being studied.
This new approach should ultimately provide a means to correctly estimate
pixel-based uncertainties in the Stokes parameters I, Q and U, including the
effect of correlations between values in different pixels.


title:
Quantitative CV-based indicators for research quality, validated by peer
  review

abstract:
  In a university, research assessments are organized at different policy
levels (faculties, research council) in different contexts (funding, council
membership, personnel evaluations). Each evaluation requires its own focus and
methodology. To conduct a coherent research policy however, data on which
different assessments are based should be well coordinated. A common set of
core indicators for any type of research assessment can provide a supportive
and objectivating tool for evaluations at different institutional levels and at
the same time promote coherent decision-making. The same indicators can also
form the basis for a 'light touch' monitoring instrument, signalling when and
where a more thorough evaluation could be considered. This poster paper shows
how peer review results were used to validate a set of quantitative indicators
for research quality for a first series of disciplines. The indicators
correspond to categories in the university's standard CV-format. Per
discipline, specific indicators are identified corresponding to their own
publication and funding characteristics. Also more globally valid indicators
are identified after normalization for discipline-characteristic performance
levels. The method can be applied to any system where peer ratings and
quantitative performance measures, both reliable and sufficiently detailed, can
be combined for the same entities.


title:
Optical frequency comb generation from aluminum nitride micro-ring
  resonator

abstract:
  Aluminum nitride is an appealing nonlinear optical material for on-chip
wavelength conversion. Here we report optical frequency comb generation from
high quality factor aluminum nitride micro-ring resonators integrated on
silicon substrates. By engineering the waveguide structure to achieve near-zero
dispersion at telecommunication wavelengths and optimizing the phase matching
for four-wave mixing, frequency combs are generated with a single wavelength
continuous-wave pump laser. The Kerr coefficient (n2) of aluminum nitride is
further extracted from our experimental results.


title: An odd (parity) test of Lorentz symmetry with atomic dysprosium

abstract:
  We propose using a Stark interference technique to directly measure the
odd-parity c_{0j} components of the electron sector c_{\mu\nu} tensor of the
Standard-Model Extension. This technique has been shown to be a sensitive probe
of parity violation in atomic dysprosium in a low-energy, tabletop experiment,
and may also be straightforwardly applied to test Lorentz invariance. We
estimate that such an experiment may be sensitive to c_{0j} coefficients as
small as 10^{-18}.


title:
Electrical conductivity of the quark-gluon plasma across the
  deconfinement transition

abstract:
  A lattice calculation is presented for the electrical conductivity of the QCD
plasma with 2+1 dynamical flavours at nonzero temperature. We employ the
conserved lattice current on anisotropic lattices using a tadpole-improved
clover action and study the behaviour of the conductivity over a wide range of
temperatures, both below and above the deconfining transition. The conductivity
is extracted from a spectral-function analysis using the Maximal Entropy Method
and a discussion of its systematics is provided.


title:
The nNJL model with a fractional Lorentzian regulator in the real time
  formalism

abstract:
  In this article we study the finite temperature and chemical potential
effects in a nonlocal Nambu-Jona-Lasinio (nNJL) model in the real time
formalism. We make the usual Wick rotation to get from imaginary to real time
formalism. In doing so, we need to define our regulator in the complex plane
q^2. This deffinition will be crucial in our later analysis. We study the poles
in the propagator of this model and conclude that only some of them are of
interst to us. Once we have a well defined model in real time formalism, we
look at the chiral condensate to find the temperature at which chiral symmetry
restoration will occur. We find a second order phase transition that turns to a
first order one for high enough values of the chemical potential.


title:
Composing a Publication List for Individual Researcher Assessment by
  Merging Information from Different Sources

abstract:
  Citation and publication profiles are gaining importance for the evaluation
of top researchers when it comes to the appropriation of funding for excellence
programs or career promotion judgments. Indicators like the Normalized Mean
Citation Rate, the hindex or other distinguishing measures are increasingly
used to picture the characteristics of individual scholars. Using bibliometric
techniques for individual assessment is known to be particularly delicate, as
the chance of errors being averaged away becomes smaller whereas a minor
incompleteness can have a significant influence on the evaluation outcome. The
quality of the data becomes as such crucial to the legitimacy of the methods
used.


title: An integer optimization problem for non-Hamiltonian periodic flows

abstract:
  Let C be the class of compact 2n-dimensional symplectic manifolds M for which
the first or (n-1) Chern class vanish. We point out an integer optimization
problem to find a lower bound B(n) on the number of equilibrium points of
non-Hamiltonian symplectic periodic flows on manifolds M in C. As a
consequence, we confirm in dimensions 2n in {8,10,12,14,18,20, 22} a conjecture
for unitary manifolds made by Kosniowski in 1979 for the subclass C.


title: Acoustic-like dynamics of amorphous drugs in the THz regime

abstract:
  The high frequency dynamics of Indomethacin and Celecoxib glasses has been
investigated by inelastic x-ray scattering, accessing a momentum-energy region
still unexplored in amorphous pharmaceuticals. We find evidence of phonon-like
acoustic dynamics, and determine the THz behavior of sound velocity and
acoustic attenuation. Connections with ordinary sound propagation are
discussed, along with the relation between fast and slow degrees of freedom as
represented by non-ergodicity factor and kinetic fragility, respectively.


title: Platonic solids generate their four-dimensional analogues

abstract:
  In this paper, we show how regular convex 4-polytopes - the analogues of the
Platonic solids in four dimensions - can be constructed from three-dimensional
considerations concerning the Platonic solids alone. Via the Cartan-Dieudonne
theorem, the reflective symmetries of the Platonic solids generate rotations.
In a Clifford algebra framework, the space of spinors generating such
three-dimensional rotations has a natural four-dimensional Euclidean structure.
The spinors arising from the Platonic Solids can thus in turn be interpreted as
vertices in four-dimensional space, giving a simple construction of the 4D
polytopes 16-cell, 24-cell, the F_4 root system and the 600-cell. In
particular, these polytopes have `mysterious' symmetries, that are almost
trivial when seen from the three-dimensional spinorial point of view. In fact,
all these induced polytopes are also known to be root systems and thus generate
rank-4 Coxeter groups, which can be shown to be a general property of the
spinor construction. These considerations thus also apply to other root systems
such as A_1+I_2(n) which induces I_2(n)+I_2(n), explaining the existence of the
grand antiprism and the snub 24-cell, as well as their symmetries. We discuss
these results in the wider mathematical context of Arnol'd's trinities and the
McKay correspondence. These results are thus a novel link between the
geometries of three and four dimensions, with interesting potential
applications on both sides of the correspondence, to real 3D systems with
polyhedral symmetries such as (quasi)crystals and viruses, as well as 4D
geometries arising for instance in Grand Unified Theories and String and
M-Theory.


title: Streaming Variational Bayes

abstract:
  We present SDA-Bayes, a framework for (S)treaming, (D)istributed,
(A)synchronous computation of a Bayesian posterior. The framework makes
streaming updates to the estimated posterior according to a user-specified
approximation batch primitive. We demonstrate the usefulness of our framework,
with variational Bayes (VB) as the primitive, by fitting the latent Dirichlet
allocation model to two large-scale document collections. We demonstrate the
advantages of our algorithm over stochastic variational inference (SVI) by
comparing the two after a single pass through a known amount of data---a case
where SVI may be applied---and in the streaming setting, where SVI does not
apply.


title: Impact Vitality - A Measure for Excellent Scientists

abstract:
  In many countries and at European level, research policy increasingly focuses
on 'excellent' researchers. The concept of excellence however is complex and
multidimensional. For individual scholars it involves talents for innovative
knowledge creation and successful transmission to peers, as well as management
capacities. Excellence is also a comparative concept, implying the ability to
surpass others [TIJSSEN, 2003]. Grants are in general awarded based on
assessments by expert committees. While peer review is a widely accepted
practice, it nevertheless is also subject to criticism. At higher aggregation
levels, peer assessments are often supported by quantitative measures. At
individual level, most of these measures are much less appropriate and there is
a need for new, dedicated indicators.


title:
Simulation of Ultra-Relativistic Electrons and Positrons Channeling in
  Crystals with MBN Explorer

abstract:
  A newly developed code, implemented as a part of the \MBNExplorer package
\cite{MBN_ExplorerPaper,MBN_ExplorerSite} to simulate trajectories of an
ultra-relativistic projectile in a crystalline medium, is presented. The motion
of a projectile is treated classically by integrating the relativistic
equations of motion with account for the interaction between the projectile and
crystal atoms. The probabilistic element is introduced by a random choice of
transverse coordinates and velocities of the projectile at the crystal entrance
as well as by accounting for the random positions of the atoms due to thermal
vibrations. The simulated trajectories are used for numerical analysis of the
emitted radiation. Initial approbation and verification of the code have been
carried out by simulating the trajectories and calculating the radiation
emitted by $\E=6.7$ GeV and $\E=855$ MeV electrons and positrons in oriented
Si(110) crystal and in amorphous silicon. The calculated spectra are compared
with the experimental data and with predictions of the Bethe-Heitler theory for
the amorphous environment.


title:
Multiwavelength observations and modeling of 1ES 1959+650 in a low flux
  state

abstract:
  We report on the VERITAS observations of the high-frequency peaked BL Lac
object 1ES 1959+650 in the period 2007-2011. This source is detected at TeV
energies by VERITAS at 16.4 standard deviation (sigma) significance in 7.6
hours of observation in a low flux state. A multiwavelength spectral energy
distribution (SED) is constructed from contemporaneous data from VERITAS,
Fermi-LAT, RXTE PCA, and Swift UVOT. Swift XRT data is not included in the SED
due to a lack of simultaneous observations with VERITAS. In contrast to the
orphan gamma-ray flare exhibited by this source in 2002, the X-ray flux of the
source is found to vary by an order of magnitude, while other energy regimes
exhibit less variable emission. A quasi-equilibrium synchrotron self-Compton
model with an additional external radiation field is used to describe three
SEDs corresponding to the lowest, highest, and average X-ray states. The
variation in the X-ray spectrum is modeled by changing the electron injection
spectral index, with minor adjustments of the kinetic luminosity in electrons.
This scenario produces small-scale flux variability of order >~2 in the HE (E>1
MeV) and VHE (E>100 GeV) gamma-ray regimes, which is corroborated by the
Fermi-LAT, VERITAS, and Whipple 10m telescope light curves.


title:
Quality related publication categories in social sciences and
  humanities, based on a university's peer review assessments

abstract:
  Bibliometric analysis has firmly conquered its place as an instrument for
evaluation and international comparison of performance levels. Consequently,
differences in coverage by standard bibliometric databases installed a
dichotomy between on the one hand the well covered 'exact' sciences, and on the
other hand most of the social sciences and humanities with a more limited
coverage (Nederhof, 2006). Also the latter domains need to be able to soundly
demonstrate their level of performance and claim or legitimate funding
accordingly. An important part of the output volume in social sciences appears
as books, book chapters and national literature (Hicks, 2004). To proceed from
publication data to performance measurement, quantitative publication counts
need to be combined with qualitative information, for example from peer
assessment or validation (European Expert Group on Assessment of
University-Based Research, 2010), to identify those categories that represent
research quality as perceived by peers. An accurate focus is crucial in order
to stimulate, recognize and reward high quality achievements only. This paper
demonstrates how such a selection of publication categories can be based on
correlations with peer judgments. It is also illustrated that the selection
should be sufficiently precise, to avoid subcategories negatively correlated
with peer judgments. The findings indicate that, also in social sciences and
humanities, publications in journals with an international referee system are
the most important category for evaluating quality. Book chapters with
international referee system and contributions in international conference
proceedings follow them.


title:
On the Perturbative Evaluation of Thermal Green's Functions in the Bulk
  and Shear Channels of Yang-Mills Theory

abstract:
  In this PhD thesis, I will review recent progress in perturbative studies of
energy momentum tensor correlators in high-temperature Yang-Mills theory. After
briefly introducing the necessary tools and physical motivation, I proceed to
discuss the machinery developed for the extraction of next-to-leading order
Operator Product Expansions and thermal spectral functions and to introduce the
results obtained in the bulk and shear channels of Yang-Mills theory.
Particular emphasis is placed on the comparison of the results with recent
lattice and gauge/gravity calculations, as well as on discussing their use in
extracting the corresponding transport coefficients from Euclidean lattice
data.


title: Lifetime and population of the 2S state in muonic protium and deuterium

abstract:
  Radiative deexcitation (RD) of the metastable 2S state of muonic protium and
deuterium atoms has been observed. In muonic protium, we improve the precision
on lifetime and population (formation probability) values for the short-lived
{\mu}p(2S) component, and give an upper limit for RD of long-lived {\mu}p(2S)
atoms. In muonic deuterium at 1 hPa, 3.1 +-0.3 % of all stopped muons form
{\mu}d(2S) atoms. The short-lived 2S component has a population of 1.35 +0.57
-0.33 % and a lifetime of {\tau}_short({\mu}d) = 138 +32 -34 ns. We see
evidence for RD of long-lived {\mu}d(2S) with a lifetime of {\tau}_long({\mu}d)
= 1.15 +0.75 -0.53 {\mu}s. This is interpreted as formation and decay of
excited muonic molecules.


title:
On artefact-free reconstruction of low-energy (30-250 eV) electron
  holograms

abstract:
  Low-energy electrons (30-250 eV) have been successfully employed for imaging
individual biomolecules. The most simple and elegant design of a low-energy
electron microscope for imaging biomolecules is a lensless setup that operates
in the holographic mode. In this work we address the problem associated with
the reconstruction from the recorded holograms. We discuss the twin image
problem intrinsic to inline holography and the problem of the so-called
biprism-like effect specific to low-energy electrons. We demonstrate how the
presence of the biprism-like effect can be efficiently identified and
circumvented. The presented sideband filtering reconstruction method eliminates
the twin image and allows for reconstruction despite the biprism-like effect,
which we demonstrate on both, simulated and experimental examples.


title: Simulations of electron channeling in bent silicon crystal

abstract:
  We report on the results of theoretical simulations of the electron
channeling in a bent silicon crystal. The dynamics of ultra-relativistic
electrons in the crystal is computed using the newly developed part [1] of the
MBN Explorer package [2,3], which simulates classical trajectories of in a
crystalline medium by integrating the relativistic equations of motion with
account for the interaction between the projectile and crystal atoms. A Monte
Carlo approach is employed to sample the incoming electrons and to account for
thermal vibrations of the crystal atoms. The electron channeling along Si(110)
crystallographic planes are studied for the projectile energies 195--855 MeV
and different curvatures of the bent crystal.


title:
Output and citation impact of interdisciplinary networks: Experiences
  from a dedicated funding program

abstract:
  In a context of ever more specialized scientists, interdisciplinarity
receives increasing attention as innovating ideas are often situated where the
disciplines meet. In many countries science policy makers installed dedicated
funding programs and policies. This induces a need for specific tools for their
support. There is however not yet a generally accepted quantitative method or
set of criteria to recognize and evaluate interdisciplinary research outputs
(Tracking and evaluating interdisciplinary research: metrics and maps, 12th
ISSI Conference, 2009). Interdisciplinarity also takes on very different forms,
as distinguished in overviews from the first codifications (Klein, 1990) to the
latest reference work (Frodeman et al., 2010). In the specific context of
research measurement and evaluation, interdisciplinarity was discussed e.g. by
Rinia (2007) and Porter et al. (2006). This empirical study aims to contribute
to the understanding and the measuring of interdisciplinary research at the
micro level, in the form of new synergies between disciplines. Investigation of
a specialized funding program shows how a new interdisciplinary synergy and its
citation impact are visible in co-publications and cocitations, and that these
are important parameters for assessment. The results also demonstrate the
effect of funding, which is clearly present after about three years.


title: Zero vs. epsilon Error in Interference Channels

abstract:
  Traditional studies of multi-source, multi-terminal interference channels
typically allow a vanishing probability of error in communication. Motivated by
the study of network coding, this work addresses the task of quantifying the
loss in rate when insisting on zero error communication in the context of
interference channels.


title: Structure of Triadic Relations in Multiplex Networks

abstract:
  Recent advances in the study of networked systems have highlighted that our
interconnected world is composed of networks that are coupled to each other
through different "layers" that each represent one of many possible subsystems
or types of interactions. Nevertheless, it is traditional to aggregate
multilayer networks into a single weighted network in order to take advantage
of existing tools. This is admittedly convenient, but it is also extremely
problematic, as important information can be lost as a result. It is therefore
important to develop multilayer generalizations of network concepts. In this
paper, we analyze triadic relations and generalize the idea of transitivity to
multiplex networks. By focusing on triadic relations, which yield the simplest
type of transitivity, we generalize the concept and computation of clustering
coefficients to multiplex networks. We show how the layered structure of such
networks introduces a new degree of freedom that has a fundamental effect on
transitivity. We compute multiplex clustering coefficients for several real
multiplex networks and illustrate why one must take great care when
generalizing standard network concepts to multiplex networks. We also derive
analytical expressions for our clustering coefficients for ensemble averages of
networks in a family of random multiplex networks. Our analysis illustrates
that social networks have a strong tendency to promote redundancy by closing
triads at every layer and that they thereby have a different type of multiplex
transitivity from transportation networks, which do not exhibit such a
tendency. These insights are invisible if one only studies aggregated networks.


title: Sum Rules for Nucleon GPDs and Border Function Formulation

abstract:
  The newy developed approach to model nucleon generalized parton distributions
(GPDs) H and E$ is based on two types of their representation in terms of
double distributions. Within this approach, we re-consider the derivation of
GPD sum rules that allow to use border functions H(x,x) and E(x,x) instead of
full GPDs H(x,\xi) and E(x,\xi) in the integrals producing Compton form factors
of deeply virtual Compton scattering. Using factorized DD Ansatz to model GPDs,
we discuss the relation between the border functions and underlying parton
densities. We find that a substantial contribution to H(x,x) border function
comes from the extra term required by new DD representations and related to
E(x,\xi) GPD.


title:
Relaxation of Bose-Einstein Condensates of Magnons in Magneto-Textural
  Traps in Superfluid $^3$He-B

abstract:
  In superfluid $^3$He-B externally pumped quantized spin-wave excitations or
magnons spontaneously form a Bose-Einstein condensate in a 3-dimensional trap
created with the order-parameter texture and a shallow minimum in the
polarizing field. The condensation is manifested by coherent precession of the
magnetization with a common frequency in a large volume. The trap shape is
controlled by the profile of the applied magnetic field and by the condensate
itself via the spin-orbit interaction. The trapping potential can be
experimentally determined with the spectroscopy of the magnon levels in the
trap. We have measured the decay of the ground state condensates after
switching off the pumping in the temperature range $(0.14\div
0.2)T_{\mathrm{c}}$. Two contributions to the relaxation are identified: (1)
spin-diffusion with the diffusion coefficient proportional to the density of
thermal quasiparticles and (2) the approximately temperature-independent
radiation damping caused by the losses in the NMR pick-up circuit. The measured
dependence of the relaxation on the shape of the trapping potential is in a
good agreement with our calculations based on the magnetic field profile and
the magnon-modified texture. Our values for the spin diffusion coefficient at
low temperatures agree with the theoretical prediction and earlier measurements
at temperatures above $0.5T_{\mathrm{c}}$.


title:
Effective coherence of groups discriminated by a locally quasi-convex
  hyperbolic group

abstract:
  We prove that every finitely generated group $G$ discriminated by a locally
quasi-convex torsion-free hyperbolic group $\Gamma$ is effectively coherent:
that is, presentations for finitely generated subgroups can be computed from
the subgroup generators. We study $G$ via its embedding into an iterated
centralizer extension of $\Gamma$, and prove that this embedding can be
computed. We also give algorithms to enumerate all finitely generated groups
discriminated by $\Gamma$ and to decide whether a given group, with decidable
word problem, is discriminated by $\Gamma$. If $\Gamma$ may have torsion, we
prove that groups obtained from $\Gamma$ by iterated amalgamated products with
virtually abelian groups, over elementary subgroups, are effectively coherent.


title:
Interdisciplinary Research Collaborations: Evaluation of a Funding
  Program

abstract:
  Innovative ideas are often situated where disciplines meet, and
socio-economic problems generally require contributions from several
disciplines. Ways to stimulate interdisciplinary research collaborations are
therefore an increasing point of attention for science policy. There is concern
that 'regular' funding programs, involving advice from disciplinary experts and
discipline-bound viewpoints, may not adequately stimulate, select or evaluate
this kind of research. This has led to specific policies aimed at
interdisciplinary research in many countries. There is however at this moment
no generally accepted method to adequately select and evaluate
interdisciplinary research. In the vast context of different forms of
interdisciplinarity, this paper aims to contribute to the debate on best
practices to stimulate and support interdisciplinary research collaborations.
It describes the selection procedures and results of a university program
supporting networks formed 'bottom up', integrating expertise from different
disciplines. The program's recent evaluation indicates that it is successful in
selecting and supporting the interdisciplinary synergies aimed for, responding
to a need experienced in the field. The analysis further confirms that
potential for interdisciplinary collaboration is present in all disciplines.


title:
Control of Intermolecular Bonds by Deposition Rates at Room Temperature:
  Hydrogen Bonds versus Metal Coordination in Trinitrile Monolayers

abstract:
  Self-assembled monolayers of 1,3,5-tris(4'-biphenyl-4"-carbonitrile)benzene,
a large functional trinitrile molecule, on the (111) surfaces of copper and
silver under ultrahigh vacuum conditions were studied by scanning tunneling
microscopy and low-energy electron diffraction. A densely packed
hydrogen-bonded polymorph was equally observed on both surfaces. Additionally,
deposition onto Cu(111) yielded a well-ordered metal-coordinated porous
polymorph that coexisted with the hydrogen-bonded structure. The required
coordination centers were supplied by the adatom gas of the Cu(111) surface. On
Ag(111), however, the well-ordered metal-coordinated network was not observed.
Differences between the adatom reactivities on copper and silver and the
resulting bond strengths of the respective coordination bonds are held
responsible for this substrate dependence. By utilizing ultralow deposition
rates, we demonstrate that on Cu(111) the adatom kinetics plays a decisive role
in the expression of intermolecular bonds and hence structure selection.


title: Bayesian inference of epidemics on networks via Belief Propagation

abstract:
  We study several bayesian inference problems for irreversible stochastic
epidemic models on networks from a statistical physics viewpoint. We derive
equations which allow to accurately compute the posterior distribution of the
time evolution of the state of each node given some observations. At difference
with most existing methods, we allow very general observation models, including
unobserved nodes, state observations made at different or unknown times, and
observations of infection times, possibly mixed together. Our method, which is
based on the Belief Propagation algorithm, is efficient, naturally distributed,
and exact on trees. As a particular case, we consider the problem of finding
the "zero patient" of a SIR or SI epidemic given a snapshot of the state of the
network at a later unknown time. Numerical simulations show that our method
outperforms previous ones on both synthetic and real networks, often by a very
large margin.


title:
Sub-GeV Electron and Positron Channeling in Straight, Bent and
  Periodically Bent Silicon Crystals

abstract:
  Preliminary results of numerical simulations of electron and positron
channeling and emission spectra are reported for straight, uniformly bent and
periodically bent silicon crystal. The projectile trajectories are computed
using the newly developed module [1] of the MBN Explorer package [2,3]. The
electron and positron channeling along Si(110) and Si(111) crystallographic
planes are studied for the projectile energies 195--855 MeV.


title:
Are observations of the galaxy cluster Abell 1689 consistent with a
  neutrino dark matter scenario?

abstract:
  Recent weak and strong lensing data of the galaxy cluster A1689 are modelled
by dark fermions that are quantum degenerate within some core. The gas density,
deduced from X-ray observations up to 1 Mpc and obeying a cored power law, is
taken as input, while the galaxy mass density is modelled. An additional dark
matter tail may arise from cold or warm dark matter, axions or non-degenerate
neutrinos. The fit yields that the fermions are degenerate within a 430 kpc
radius. The fermion mass is a few eV and the best case involves 3 active plus 3
sterile neutrinos of equal mass, for which we deduce $1.51 \pm 0.04$ eV. The eV
mass range will be tested in the KATRIN experiment.


title: Optimal Top-k Document Retrieval

abstract:
  Let $\mathcal{D}$ be a collection of $D$ documents, which are strings over an
alphabet of size $\sigma$, of total length $n$. We describe a data structure
that uses linear space and and reports $k$ most relevant documents that contain
a query pattern $P$, which is a string of length $p$, in time $O(p/\log_\sigma
n+k)$, which is optimal in the RAM model in the general case where $\lg D =
\Theta(\log n)$, and involves a novel RAM-optimal suffix tree search. Our
construction supports an ample set of important relevance measures... [clip]
  When $\lg D = o(\log n)$, we show how to reduce the space of the data
structure from $O(n\log n)$ to $O(n(\log\sigma+\log D+\log\log n))$ bits...
[clip]
  We also consider the dynamic scenario, where documents can be inserted and
deleted from the collection. We obtain linear space and query time
$O(p(\log\log n)^2/\log_\sigma n+\log n + k\log\log k)$, whereas insertions and
deletions require $O(\log^{1+\epsilon} n)$ time per symbol, for any constant
$\epsilon>0$.
  Finally, we consider an extended static scenario where an extra parameter
$par(P,d)$ is defined, and the query must retrieve only documents $d$ such that
$par(P,d)\in [\tau_1,\tau_2]$, where this range is specified at query time. We
solve these queries using linear space and $O(p/\log_\sigma n +
\log^{1+\epsilon} n + k\log^\epsilon n)$ time, for any constant $\epsilon>0$.
  Our technique is to translate these top-$k$ problems into multidimensional
geometric search problems. As an additional bonus, we describe some
improvements to those problems.


title:
Negative differential resistance with graphene channels, interfacing
  distributed quantum dots in Field-Effect Transistors

abstract:
  Field effect transistors with channels made of graphene layer(s) were
explored. The graphene layer(s) contacted a distributed array of well-separated
semiconductor quantum dots (QDs). The dots were embedded in nano-structured
hole-array; each filled hole was occupied by one dot. Differential optical and
electrical conductance was observed. Since Negative Differential Resistance
(NDR) is key to high-speed elements, such construction may open the door for
new electro-photonic devices.


title: Research Excellence Milestones of BRIC and N-11 Countries

abstract:
  While scientific performance is an important aspect of a stable and healthy
economy, measures for it have yet to gain their place in economic country
profiles. As useful indicators for this performance dimension, this paper
introduces the concept of milestones for research excellence, as points of
transition to higher-level contributions at the leading edge of science. The
proposed milestones are based on two indicators associated with research
excellence, the impact vitality profile and the production of review type
publications, both applied to a country's publications in the top journals
Nature and Science. The milestones are determined for two distinct groups of
emerging market economies: the BRIC countries, which outperformed the relative
growth expected at their identification in 2001, and the N-11 or Next Eleven
countries, identified in 2005 as potential candidates for a BRIC-like
evolution. Results show how these two groups at different economic levels can
be clearly distinguished based on the research milestones, indicating a
potential utility as parameters in an economic context.


title:
Characteristics of International versus Non-International Scientific
  Publication Media in Team- and Author-Based Data

abstract:
  The enlarged coverage of the international publication and citation databases
Web of Science and Scopus towards local media in social sciences was a welcome
response to an increased usage of these databases in evaluation and funding
systems. The mostly international journals available earlier were the basis for
the development of current standard bibliometric indicators. The same
indicators may no longer measure exactly the same concepts when applied to
newly introduced or extended media categories, with possibly different
characteristics than those of international journals. This paper investigates
differences between media with and without international dimension in
publication data at team and author level. The findings relate the
international publication categories to research quality, important for
validation of their usage in evaluation or funding models that aim to stimulate
quality.


title:
Next-to-leading tail-induced spin-orbit effects in the gravitational
  radiation flux of compact binaries

abstract:
  The imprint of non-linearities in the propagation of gravitational waves ---
the tail effect --- is responsible for new spin contributions to the energy
flux and orbital phasing of spinning black hole binaries. The spin-orbit
(linear in spin) contribution to this effect is currently known at leading
post-Newtonian order, namely 3PN for maximally spinning black holes on
quasi-circular orbits. In the present work, we generalize these tail-originated
spin-orbit terms to the next-to-leading 4PN order. This requires in particular
extending previous results on the dynamical evolution of precessing compact
binaries. We show that the tails represent the only spin-orbit terms at that
order for quasi-circular orbits, and we find perfect agreement with the known
result for a test particle around a Kerr black hole, computed by perturbation
theory. The BH-horizon absorption terms have to be added to the PN result
computed here. Our work completes the knowledge of the spin-orbit effects to
the phasing of compact binaries up to the 4PN order, and will allow the
building of more faithful PN templates for the inspiral phase of black hole
binaries, improving the capabilities of ground-based and space-based
gravitational wave detectors.


title: Quasi-affine Nichols (Lie braided) Algebras with Rank $ 4$

abstract:
  All quasi-affine connected Generalized Dynkin Diagram with rank $= 4$ are
found. All quasi-affine Nichols (Lie braided) algebras with rank $ 4$ are also
found.


title:
Dynamics of isolated-photon plus jet production in pp collisions at
  sqrt(s)=7 TeV with the ATLAS detector

abstract:
  The dynamics of isolated-photon plus jet production in pp collisions at a
centre-of-mass energy of 7 TeV has been studied with the ATLAS detector at the
LHC using an integrated luminosity of 37 pb-1. Measurements of isolated-photon
plus jet bin-averaged cross sections are presented as functions of photon
transverse energy, jet transverse momentum and jet rapidity. In addition, the
bin-averaged cross sections as functions of the difference between the
azimuthal angles of the photon and the jet, the photon--jet invariant mass and
the scattering angle in the photon--jet centre-of-mass frame have been
measured. Next-to-leading-order QCD calculations are compared to the
measurements and provide a good description of the data, except for the case of
the azimuthal opening angle.


title:
Multiplicity Dependence of Pion, Kaon, Proton and Lambda Production in
  p-Pb Collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV

abstract:
  In this Letter, comprehensive results on ${\rm\pi}^\pm$, K$^\pm$, K$^0_S$, p,
$\rm\bar{p}$, $\rm \Lambda$ and $\rm \bar{\Lambda}$ production at mid-rapidity
($0 < y_{\rm cms} < 0.5$) in p-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV,
measured by the ALICE detector at the LHC, are reported. The transverse
momentum distributions exhibit a hardening as a function of event multiplicity,
which is stronger for heavier particles. This behavior is similar to what has
been observed in pp and Pb-Pb collisions at the LHC. The measured $p_{\rm T}$
distributions are compared to results at lower energy and with predictions
based on QCD-inspired and hydrodynamic models.


title:
Groups of Highly Cited Publications: Stability in Content with Citation
  Window Length

abstract:
  The growing focus in research policy worldwide on top scientists makes it
increasingly important to define adequate supporting measures to help identify
excellent scientists. Highly cited publications have since long been associated
to research excellence. At the same time, the analysis of the high-end of
citation distributions still is a challenging topic in evaluative
bibliometrics. Evaluations typically require indicators that generate
sufficiently stable results when applied to recent publication records of
limited size. Highly cited publications have been identified using two
techniques in particular: pre-set percentiles, and the parameter free
Characteristic Scores and Scales (CSS) (Gl\"anzel & Schubert, 1988). The
stability required in assessments of relatively small publication records,
concerns size as well as content of groups of highly cited publications.
Influencing factors include domain delineation and citation window length.
Stability in size is evident for the pre-set percentiles, and has been
demonstrated for the CSS-methodology beyond an initial citation period of about
three years (Gl\"anzel, 2007). Stability in content is less straightforward,
considering for instance that more highly cited publications can have a later
citation peak, as observed by Abt (1981) for astronomical papers. This paper
investigates the stability in content of groups of highly cited publications,
i.e. the extent to which individual publications enter and leave the group as
the citation window is enlarged.


title: StellarICs: Stellar and solar Inverse Compton emission package

abstract:
  StellarICs is software to compute gamma-ray emission from inverse-Compton
scattering by cosmic-ray leptons in the heliosphere and in the photospheres of
stars. It includes a set of cosmic-ray spectra and a formulation of their
modulation, but it can be used for any user-defined modulation model and lepton
spectra. Inverse-Compton emission provides a unique probe of cosmic-ray leptons
in the heliosphere between the earth and the sun. The software is publicly
available and it is under continuing development.


title:
A Census of Quasar-Intrinsic Absorption in the Hubble Space Telescope
  Archive: Systems from High Resolution Echelle Spectra

abstract:
  We present a census of z(abs) < 2, intrinsic (those showing partial coverage)
and associated [z(abs) ~ z(em)] quasar absorption-line systems detected in the
Hubble Space Telescope archive of Space Telescope Imaging Spectrograph echelle
spectra. This work complements the Misawa et al. (2007) survey of 2 < z(em) < 4
quasars that selects systems using similar techniques. We confirm the existence
of so-called "strong N V" intrinsic systems (where the equivalent width of H I
Ly alpha is small compared to N V 1238) presented in that work, but find no
convincing cases of "strong C IV" intrinsic systems at low redshift/luminosity.
Moreover, we also report on the existence of "strong O VI" systems. From a
comparison of partial coverage results as a function of ion, we conclude that
systems selected by the N V ion have the highest probability of being
intrinsic. By contrast, the C IV and O VI ions are poor selectors. Of the 30 O
VI systems tested, only two of the systems in the spectrum on 3C 351 show
convincing evidence for partial coverage. However, there is a 3-sigma excess in
the number of absorbers near the quasar redshift (|Delta v| <= 5000 km/s) over
absorbers at large redshift differences. In at least two cases, the associated
O VI systems are known not to arise close to the accretion disk of the quasar.


title: What happens at the horizon(s) of an extreme black hole?

abstract:
  A massless scalar field exhibits an instability at the event horizon of an
extreme black hole. We study numerically the nonlinear evolution of this
instability for spherically symmetric perturbations of an extreme
Reissner-Nordstrom (RN) black hole. We find that generically the endpoint of
the instability is a non-extreme RN solution. However, there exist fine-tuned
initial perturbations for which the instability never decays. In this case, the
perturbed spacetime describes a time-dependent extreme black hole. Such
solutions settle down to extreme RN outside, but not on, the event horizon. The
event horizon remains smooth but certain observers who cross it at late time
experience large gradients there. Our results indicate that these dynamical
extreme black holes admit a C^1 extension across an inner (Cauchy) horizon.


title: Energy landscape theory for cotranslational protein folding

abstract:
  Energy landscape theory describes how a full-length protein can attain its
native fold after sampling only a tiny fraction of all possible structures.
Although protein folding is now understood to be concomitant with synthesis on
the ribosome there have been few attempts to modify energy landscape theory by
accounting for cotranslational folding. This paper introduces a model for
cotranslational folding that leads to a natural definition of a nested energy
landscape. By applying concepts drawn from submanifold differential geometry
the dynamics of protein folding on the ribosome can be explored in a
quantitative manner and conditions on the nested potential energy landscapes
for a good cotranslational folder are obtained. A generalisation of diffusion
rate theory using van Kampen's technique of composite stochastic processes is
then used to account for entropic contributions and the effects of variable
translation rates on cotranslational folding. This stochastic approach agrees
well with experimental results and Hamiltionian formalism in the deterministic
limit.


title: Modules over the Noncommutative Torus and Elliptic Curves

abstract:
  Using the Weil-Brezin-Zak transform of solid state physics, we describe line
bundles over elliptic curves in terms of Weyl operators. We then discuss the
connection with finitely-generated projective modules over the algebra
$A_\theta$ of the noncommutative torus. We show that such $A_\theta$-modules
have a natural interpretation as Moyal deformations of vector bundles over an
elliptic curve $E_\tau$, under the condition that the deformation parameter
$\theta$ and the modular parameter $\tau$ satisfy a non-trivial relation.


title:
Martingale and Pathwise Solutions to the Stochastic Zakharov-Kuznetsov
  Equation with Multiplicative Noise

abstract:
  We study in this article the stochastic Zakharov-Kuznetsov equation driven by
a multiplicative noise. We establish, in space dimensions two and three the
global existence of martingale solutions, and in space dimension two the global
pathwise uniqueness and the existence of pathwise solutions. New methods are
employed in the passage to the limit on a special type of boundary conditions
and in the verification of the pathwise uniqueness of martingale solutions with
a lack of regularity, where both difficulties arise due to the partly
hyperbolic feature of the model.


title:
Partition-based Field Normalization: An approach to highly specialized
  publication records

abstract:
  Field normalized citation rates are well-established indicators for research
performance from the broadest aggregation levels such as countries, down to
institutes and research teams. When applied to still more specialized
publication sets at the level of individual scientists, also a more accurate
delimitation is required of the reference domain that provides the expectations
to which a performance is compared. This necessity for sharper accuracy
challenges standard methodology based on predefined subject categories. This
paper proposes a way to define a reference domain that is more strongly
delimited than in standard methodology, by building it up out of cells of the
partition created by the pre-defined subject categories and their
intersections. This partition approach can be applied to different existing
field normalization variants. The resulting reference domain lies between those
generated by standard field normalization and journal normalization. Examples
based on fictive and real publication records illustrate how the potential
impact on results can exceed or be smaller than the effect of other currently
debated normalization variants, depending on the case studied. The proposed
Partition-based Field Normalization is expected to offer advantages in
particular at the level of individual scientists and other very specific
publication records, such as publication output from interdisciplinary
research.


title: High-Energy Radiation from Remnants of Neutron Star Binary Mergers

abstract:
  We study high-energy emission from the mergers of neutron star binaries as
electromagnetic counterparts to gravitational waves aside from short gamma-ray
bursts. The mergers entail significant mass ejection, which interacts with the
surrounding medium to produce similar but brighter remnants than supernova
remnants in a few years. We show that electrons accelerated in the remnants can
produce synchrotron radiation in X-rays detectable at $\sim 100$ Mpc by current
generation telescopes and inverse Compton emission in gamma rays detectable by
the \emph{Fermi} Large Area Telescopes and the Cherenkov Telescope Array under
favorable conditions. The remnants may have already appeared in high-energy
surveys such as the Monitor of All-sky X-ray Image and the \emph{Fermi} Large
Area Telescope as unidentified sources. We also suggest that the merger
remnants could be the origin of ultra-high-energy cosmic rays beyond the knee
energy, $\sim 10^{15}$ eV, in the cosmic-ray spectrum.


title:
Detection of Earth-mass and Super-Earth Trojan Planets Using Transit
  Timing Variation Method

abstract:
  We have carried out an extensive study of the possibility of the detection of
Earth-mass and super-Earth Trojan planets using transit timing variation method
with the Kepler space telescope. We have considered a system consisting of a
transiting Jovian-type planet in a short period orbit, and determined the
induced variations in its transit timing due to an Earth-mass/super-Earth
Trojan planet. We mapped a large section of the phase space around the 1:1
mean-motion resonance and identified regions corresponding to several other
mean-motion resonances where the orbit of the planet would be stable. We
calculated TTVs for different values of the mass and orbital elements of the
transiting and perturbing bodies as well as the mass of central star, and
identified orbital configurations of these objects (ranges of their orbital
elements and masses) for which the resulted TTVs would be within the range of
the variations of the transit timing of Kepler's planetary candidates. Results
of our study indicate that in general, the amplitudes of the TTVs fall within
the detectable range of timing precision obtained from the Kepler's
long-cadence data, and depending on the parameters of the system, their
magnitudes may become as large as a few hours. The probability of detection is
higher for super-Earth Trojans with slightly eccentric orbits around
short-period Jovian-type planets with masses slightly smaller than Jupiter. We
present the details of our study and discuss the implications of its results.


title:
Asymptotic behaviour of solutions to the stationary Navier-Stokes
  equations in two dimensional exterior domains with zero velocity at infinity

abstract:
  We investigate analytically and numerically the existence of stationary
solutions converging to zero at infinity for the incompressible Navier-Stokes
equations in a two-dimensional exterior domain. More precisely, we find the
asymptotic behaviour for such solutions in the case where the net force on the
boundary of the domain is non-zero. In contrast to the three dimensional case,
where the asymptotic behaviour is given by a scale invariant solution, the
asymptote in the two-dimensional case is not scale invariant and has a wake. We
provide an asymptotic expansion for the velocity field at infinity, which shows
that, within a wake of width $|\boldsymbol{x}|^{2/3}$, the velocity decays like
$|\boldsymbol{x}|^{-1/3}$, whereas outside the wake, it decays like
$|\boldsymbol{x}|^{-2/3}$. We check numerically that this behaviour is accurate
at least up to second order and demonstrate how to use this information to
significantly improve the numerical simulations. Finally, in order to check the
compatibility of the present results with rigorous results for the case of zero
net force, we consider a family of boundary conditions on the body which
interpolate between the non-zero and the zero net force case.


title: Fusion procedure for the Yang-Baxter equation and Schur-Weyl duality

abstract:
  We use the fusion formulas of the symmetric group and of the Hecke algebra to
construct solutions of the Yang-Baxter equation on irreducible representations
of $\mathfrak{gl}_N$, $\mathfrak{gl}_{N|M}$, $U_q(\mathfrak{gl}_N)$ and
$U_q(\mathfrak{gl}_{N|M})$. The solutions are obtained via the fusion procedure
for the Yang--Baxter equation, which is reviewed in a general setting.
Distinguished invariant subspaces on which the fused solutions act are also
studied in the general setting, and expressed, in general, with the help of a
fusion function. Only then, the general construction is specialised to the four
situations mentioned above. In each of these four cases, we show how the
distinguished invariant subspaces are identified as irreducible
representations, using the relevant fusion formula combined with the relevant
Schur--Weyl duality.


title: A strongly polynomial algorithm for generalized flow maximization

abstract:
  A strongly polynomial algorithm is given for the generalized flow
maximization problem. It uses a new variant of the scaling technique, called
continuous scaling. The main measure of progress is that within a strongly
polynomial number of steps, an arc can be identified that must be tight in
every dual optimal solution, and thus can be contracted. As a consequence of
the result, we also obtain a strongly polynomial algorithm for the linear
feasibility problem with at most two nonzero entries per column in the
constraint matrix.


title: Impact dynamics of granular jets with non-circular cross-sections

abstract:
  Using high-speed photography, we investigate two distinct regimes of the
impact dynamics of granular jets with non-circular cross-sections. In the
steady-state regime, we observe the formation of thin granular sheets with
anisotropic shapes and show that the degree of anisotropy increases with the
aspect ratio of the jet's cross-section. Our results illustrate the liquid-like
behavior of granular materials during impact and demonstrate that a collective
hydrodynamic flow emerges from strongly interacting discrete particles. We
discuss the analogy between our experiments and those from the Relativistic
Heavy Ion Collider (RHIC), where similar anisotropic ejecta from a quark-gluon
plasma have been observed in heavy-ion impact.


title: Imaging of weak phase objects with a Zernike phase plate

abstract:
  Analysis of the imaging of some simple distributions of object phase by a
phase plate of Zernike type shows that sharp transitions in the object phase
are well transmitted. The low-frequency components of the complete object
function are attenuated by the plate. The behaviour can be characterised by a
cut-on parameter defined as the product of the cut-on frequency of the plate
and a characteristic dimension of the object. When this parameter exceeds a
value of the order of unity, a sharp boundary in the object is imaged by a
Zernike plate as a dark lining inside the boundary with a white outline or halo
outside the boundary, in agreement with reported observations. The maximum
diameter of objects that can be imaged accurately is inversely proportional to
the diameter of the hole for beam transmission in the phase plate.


title:
The Geometry of the Conjugacy Problem in Wreath Products and Free
  Solvable Groups

abstract:
  We describe an effective version of the conjugacy problem and study it for
wreath products and free solvable groups. The problem involves estimating the
length of short conjugators between two elements of the group, a notion which
leads to the definition of the conjugacy length function. We show that for free
solvable groups the conjugacy length function is at most cubic. For wreath
products the behaviour depends on the conjugacy length function of the two
groups involved, as well as subgroup distortion within the quotient group.


title: Contact parameters in two dimensions for general three-body systems

abstract:
  We study the two dimensional three-body problem in the general case of three
distinguishable particles interacting through zero-range potentials. The
Faddeev decomposition is used to write the momentum-space wave function. We
show that the large-momentum asymptotic spectator function has the same
functional form as derived previously for three identical particles. We derive
analytic relations between the three different Faddeev components for three
distinguishable particles. We investigate the one-body momentum distributions
both analytically and numerically and analyze the tail of the distributions to
obtain two- and three-body contact parameters. We specialize from the general
cases to examples of two identical, interacting or non-interacting, particles.
We find that the two-body contact parameter is not a universal constant in the
general case and show that the universality is recovered when a subsystem is
composed of two identical non-interacting particles. We also show that the
three-body contact parameter is negligible in the case of one non-interacting
subsystem compared to the situation where all subsystem are bound. As example,
we present results for mixtures of Lithium with two Cesium or two Potassium
atoms, which are systems of current experimental interest.

categories: cond-mat.quant-gas math-ph math.MP nucl-th quant-ph


title: A Propound Method for the Improvement of Cluster Quality

abstract:
  In this paper Knockout Refinement Algorithm (KRA) is proposed to refine
original clusters obtained by applying SOM and K-Means clustering algorithms.
KRA Algorithm is based on Contingency Table concepts. Metrics are computed for
the Original and Refined Clusters. Quality of Original and Refined Clusters are
compared in terms of metrics. The proposed algorithm (KRA) is tested in the
educational domain and results show that it generates better quality clusters
in terms of improved metric values.


title:
Planck intermediate results. XIV. Dust emission at millimetre
  wavelengths in the Galactic plane

abstract:
  We use Planck HFI data combined with ancillary radio data to study the
emissivity index of the interstellar dust emission in the frequency range 10 -
353 GHz, or 3 - 0.8 mm, in the Galactic plane. We analyse the region l=20 degr
- 44 degr and |b| \leq 4 degr where the free-free emission can be estimated
from radio recombination line data. We fit the spectra at each sky pixel with a
modified blackbody model and two spectral indices, beta_mm and beta_FIR, below
and above 353 GHz respectively. We find that beta_mm is smaller than beta_FIR
and we detect a correlation between this low frequency power-law index and the
dust optical depth at 353 GHz, tau_353. The opacity spectral index beta_mm
increases from about 1.54 in the more diffuse regions of the Galactic disk, |b|
= 3 degr - 4 degr and tau_353 ~ 5 x 10^{-5}, to about 1.66 in the densest
regions with an optical depth of more than one order of magnitude higher. We
associate this correlation with an evolution of the dust emissivity related to
the fraction of molecular gas along the line of sight. This translates into
beta_mm ~ 1.54 for a medium that is mostly atomic and beta_mm ~ 1.66 when the
medium is dominated by molecular gas. We find that both the Two-Level System
model and the emission by ferromagnetic particles can explain the results. The
results improve our understanding of the physics of interstellar dust and lead
towards a complete model of the dust spectrum of the Milky Way from
far-infrared to millimetre wavelengths.


title: General Dynamics of Varying-Alpha Universes

abstract:
  We introduce and study extensions of the varying alpha theory of
Bekenstein-Sandvik-Barrow-Magueijo to allow for an arbitrary coupling function
and self-interaction potential term in the theory. We study the full evolution
equations without assuming that variations in alpha have a negligible effect on
the expansion scale factor and the matter density evolution, as was assumed in
earlier studies. The background FRW cosmology of this model in the cases of
zero and non-zero spatial curvature is studied in detail, using dynamical
systems techniques, for a wide class of potentials and coupling functions. All
the asymptotic behaviours are found, together with some new solutions. We study
the cases where the electromagnetic parameter, zeta, is positive and negative,
corresponding to magnetic and electrostatic energy domination in the
non-relativistic matter. In particular, we investigate the cases where the
scalar field driving alpha variations has exponential and power-law
self-interaction potentials and the behaviour of theories where the coupling
constant between matter and alpha variations is no longer a constant.


title:
Ferromagnetic Quantum Criticality Studied by Hall Effect Measurements in
  UCoAl

abstract:
  Hall effect measurements were performed under pressure and magnetic field up
to 2.2 GPa and 16 T on a single crystal of UCoAl. At ambient pressure, the
system undergoes a first order metamagnetic transition at the critical field
B_m = 0.7 T from a paramagnetic ground state to a field-induced ferromagnetic
state. The Hall signal is linear at low field and shows a step-like anomaly at
the transition, with only little change of the Hall coefficient. The anomaly is
sharpest at the temperature of the critical end point T_0 = 12 K above which
the first order metamagnetic transition becomes a crossover. Under pressure B_m
increases and T_0 decreases. The step-like anomaly in the Hall effect
disappears at P_M ~= 1.3 GPa and the metamagnetic transition is not detected
above the quantum critical end point (QCEP) at P_Delta ~= 1.7 GPa, B_m ~= 7 T.
Using magnetization data, we analyse our Hall resistivity data at ambient
pressure in order to quantitatively account for both ordinary and anomalous
contributions to the Hall effect. Under pressure, a drastic change in the field
dependence of the Hall coefficient is found on crossing the QCEP. A possible
Fermi surface change at B_m remains an open question.


title: Percolation on random triangulations and stable looptrees

abstract:
  We study site percolation on Angel & Schramm's uniform infinite planar
triangulation. We compute several critical and near-critical exponents, and
describe the scaling limit of the boundary of large percolation clusters in all
regimes (subcritical, critical and supercritical). We prove in particular that
the scaling limit of the boundary of large critical percolation clusters is the
random stable looptree of index 3/2, which was introduced in a companion paper.
We also give a conjecture linking looptrees of any index in (1,2) with scaling
limits of cluster boundaries in random triangulations decorated with O(N)
models.


title: Knotted Nematics

abstract:
  Knotted line defects in continuous fields entrain a complex arrangement of
the material sur- rounding them. Recent experimental realisations in optics,
fluids and nematic liquid crystals make it important to fully characterise
these textures and to understand how their properties relate to the knot type.
We characterise knotted nematics through an application of classical knot
theory founded upon the Pontryagin-Thom construction for nematic textures and
give explicit closed form constructions for knots possessing Milnor fibrations
with general boundary conditions. For links we construct nematic textures
corresponding to all possible assigments of linking numbers and discuss the
relevance to recent, and classic, experiments on Hopf links.


title:
Generation of four-photon polarization entangled state based on EPR
  entanglers

abstract:
  We show how to prepare four-photon polarization entangled states based on
some Einstein-Podolsky-Rosen (EPR) entanglers. An EPR entangler consists of two
single photons, linear optics elements, quantum non-demolition measurement
using a weak cross-Kerr nonlinearity, and classical feed forward. This
entangler which acts as the most primary part in the construction of our scheme
allows us to make two separable polarization qubits entangled near
deterministically. Therefore, the efficiency of the present device completely
depends on that of EPR entanglers, and it has a high success probability.


title: The Earth's Equilibrium Climate Sensitivity and Thermal Inertia

abstract:
  The Earth's equilibrium climate sensitivity has received much attention
because of its relevance and importance for global warming policymaking. This
paper focuses on the Earth's \emph{thermal inertia time scale} which has
received relatively little attention. The difference between the observed
transient climate sensitivity and the equilibrium climate sensitivity is shown
to be proportional to the thermal inertia time scale, and the numerical value
of the proportionality factor is determined using recent observational data.
  Many useful policymaking insights can be extracted from the resulting
empirical quantitative relation.