title:
Microscopic driving theory with non-hypothetical congested steady state:
  Model and Empirical verification

abstract:
  The essential distinction between the fundamental diagram approach and
three-phase theory is the existence of the unique space-gap-speed relationship.
In order to verify this relationship, empirical data are analyzed with the
following findings: (1) linear relationship between the actual space gap and
speed can be identified when the speed difference between vehicles approximates
zero; (2) vehicles accelerate or decelerate around the desired space gap most
of the time. To explain these phenomena, we propose that, in homogeneous
congested traffic flow, the space gap between two vehicles will oscillate
around the desired space gap in the noiseless limit. This assumption is
formulated in terms of a cellular automaton. Simulations under periodic and
open boundary conditions reproduce the empirical findings of three-phase
theory. Finally, the model is calibrated and validated. All verification
results are acceptable and better than that of previous studies.


title: Past quantum states

abstract:
  A density matrix {\rho}(t) yields probabilistic information about the outcome
of measurements on a quantum system. We introduce here the past quantum state,
which, at time T, accounts for the state of a quantum system at earlier times t
< T. The past quantum state {\Xi}(t) is composed of two objects, {\rho}(t) and
E(t), conditioned on the dynamics and the probing of the system until t and in
the time interval [t, T], respectively. The past quantum state is characterized
by its ability to make better predictions for the unknown outcome of projective
and weak value measurements at t than the conventional quantum state at that
time. On the one hand, our formalism shows how smoothing procedures for
estimation of past classical signals by a quantum probe [M. Tsang, Phys. Rev.
Lett. 102, 250403, (2009)] apply also to describe the past state of the quantum
system itself. On the other hand, it generalizes theories of pre- and
post-selected quantum states [Y. Aharonov and L. Vaidman, J. Phys. A: Math.
Gen. 24, 2315 (1991)] to systems subject to any quantum measurement scenario,
any coherent evolution, and any Markovian dissipation processes.


title:
Procedure to construct a multi-scale coarse-grained model of DNA-coated
  colloids from experimental data

abstract:
  We present a quantitative, multi-scale coarse-grained model of DNA coated
colloids. The parameters of this model are transferable and are solely based on
experimental data. As a test case, we focus on nano-sized colloids carrying
single-stranded DNA strands of length comparable to the colloids' size. We show
that in this regime, the common theoretical approach of assuming pairwise
additivity of the colloidal pair interactions leads to quantitatively and
sometimes even qualitatively wrong predictions of the phase behaviour of
DNA-grafted colloids. Comparing to experimental data, we find that our
coarse-grained model correctly predicts the equilibrium structure and melting
temperature of the formed solids. Due to limited experimental information on
the persistence length of single-stranded DNA, some quantitative discrepancies
are found in the prediction of spatial quantities. With the availability of
better experimental data, the present approach provides a path for the rational
design of DNA-functionalised building blocks that can self-assemble in complex,
three-dimensional structures.


title:
Soliton Coupling Effect: Group-velocity-matching Dispersive Wave
  Generation and Spectral Tunneling

abstract:
  Concept of spectral soliton coupling is proposed to explain the
group-velocity-matching dispersive wave generation and the soliton spectral
tunneling effect. Soliton eigen state is found corresponding to a spectral
phase profile under which the soliton phase shifts induced by the dispersion
and the nonlinearity are instantaneously counterbalanced. A local but non-eigen
soliton pulse will shed off energy and form radiations at other wavelengths,
during the coupling to the soliton eigen state. Group-velocity-mathing between
the local and generated wave is necessary not only as it produces a
coupler-like phase profile which supports soliton coupling but also because it
physically supports a soliton phase matching condition, which means the
generated wave has a soliton state phase matched to the local exciting pulse.
Examples in realistic photonic crystal fiber structures are also presented.


title: Super-linear scaling of offsprings at criticality in branching processes

abstract:
  For any branching process, we demonstrate that the typical total number
$r_{\rm mp}(\nu \tau)$ of events triggered over all generations within any
sufficiently large time window $\tau$ exhibits, at criticality, a super-linear
dependence $r_{\rm mp}(\nu \tau) \sim (\nu \tau)^\gamma$ (with $\gamma >1$) on
the total number $\nu \tau$ of the immigrants arriving at the Poisson rate
$\nu$. In branching processes in which immigrants (or sources) are
characterized by fertilities distributed according to an asymptotic power law
tail with tail exponent $1 < \gamma \leqslant 2$, the exponent of the
super-linear law for $r_{\rm mp}(\nu \tau)$ is identical to the exponent
$\gamma$ of the distribution of fertilities. For $\gamma>2$ and for standard
branching processes without power law distribution of fertilities, $r_{\rm
mp}(\nu \tau) \sim (\nu \tau)^2$. This novel scaling law replaces and tames the
divergence $\nu \tau/(1-n)$ of the mean total number ${\bar R}_t(\tau)$ of
events, as the branching ratio (defined as the average number of triggered
events of first generation per source) tends to 1. The derivation uses the
formalism of generating probability functions. The corresponding prediction is
confirmed by numerical calculations and an heuristic derivation enlightens its
underlying mechanism. We also show that ${\bar R}_t(\tau)$ is always linear in
$\nu \tau$ even at criticality ($n=1$). Our results thus illustrate the
fundamental difference between the mean total number, which is controlled by a
few extremely rare realizations, and the typical behavior represented by
$r_{\rm mp}(\nu \tau)$.


title: Invariant triple functionals over $U_q\frak{sl}_2$

abstract:
  We define a $q$-deformation of Jacquet-Langlands principal series
representations of $GL_2(R)$ and prove the uniqueness of an invariant triple
functional on them using the method of H.Y.Loke.


title: Network-like propagation of cell-level stress in random foams

abstract:
  Quasistatic simple shearing flow of random monodisperse soap froth is
investigated by analyzing Surface Evolver simulations of spatially periodic
foams. Elastic-plastic behavior is caused by irreversible topological
rearrangements (T1s) that occur when Plateau's laws are violated; the first T1s
occur at the elastic limit and at large strains frequent cascades of T1s,
composed of one or more individual T1s, sustain the yield-stress plateau. The
stress and shape anisotropy of individual cells is quantified by $Q$, a scalar
measure derived from the interface tensor that gauges each cell's contribution
to the global stress. During each T1 cascade, the connected set of cells with
decreasing $Q$, called the \textit{stress release domain}, is network-like and
highly non-local. Geometrically, the network-like nature of the stress release
domains is corroborated through morphological analysis using the Euler
characteristic. The stress release domain is distinctly different from the set
of cells that change topology during a T1 cascade. Our results highlight the
unique rheological behavior of foams, where complex large-scale cooperative
rearrangements of foam cells are observed as a consequence of distinctly local
events.


title: Computer Algebra Algorithms for Special Functions in Particle Physics

abstract:
  This work deals with special nested objects arising in massive higher order
perturbative calculations in renormalizable quantum field theories. On the one
hand we work with nested sums such as harmonic sums and their generalizations
(S-sums, cyclotomic harmonic sums, cyclotomic S-sums) and on the other hand we
treat iterated integrals of the Poincar\'e and Chen-type, such as harmonic
polylogarithms and their generalizations (multiple polylogarithms, cyclotomic
harmonic polylogarithms). The iterated integrals are connected to the nested
sums via (generalizations of) the Mellin-transformation and we show how this
transformation can be computed. We derive algebraic and structural relations
between the nested sums as well as relations between the values of the sums at
infinity and connected to it the values of the iterated integrals evaluated at
special constants. In addition we state algorithms to compute asymptotic
expansions of these nested objects and we state an algorithm which rewrites
certain types of nested sums into expressions in terms of cyclotomic S-sums.
Moreover we summarize the main functionality of the computer algebra package
HarmonicSums in which all these algorithms and transformations are implemented.
Furthermore, we present application of and enhancements of the multivariate
Almkvist-Zeilberger algorithm to certain types of Feynman integrals and the
corresponding computer algebra package MultiIntegrate.


title: On Flexible Web Services Composition Networks

abstract:
  The semantic Web service community develops efforts to bring semantics to Web
service descriptions and allow automatic discovery and composition. However,
there is no widespread adoption of such descriptions yet, because semantically
defining Web services is highly complicated and costly. As a result, production
Web services still rely on syntactic descriptions, key-word based discovery and
predefined compositions. Hence, more advanced research on syntactic Web
services is still ongoing. In this work we build syntactic composition Web
services networks with three well known similarity metrics, namely Levenshtein,
Jaro and Jaro-Winkler. We perform a comparative study on the metrics
performance by studying the topological properties of networks built from a
test collection of real-world descriptions. It appears Jaro-Winkler finds more
appropriate similarities and can be used at higher thresholds. For lower
thresholds, the Jaro metric would be preferable because it detect less
irrelevant relationships.


title:
Photophoretic separation of metals and silicates: the formation of
  Mercury like planets and metal depletion in chondrites

abstract:
  Mercury's high uncompressed mass density suggests that the planet is largely
composed of iron, either bound within metal (mainly Fe-Ni), or iron sulfide.
Recent results from the MESSENGER mission to Mercury imply a low temperature
history of the planet which questions the standard formation models of impact
mantle stripping or evaporation to explain the high metal content. Like
Mercury, the two smallest extrasolar rocky planets with mass and size
determination, CoRoT-7b and Kepler-10b, were found to be of high density. As
they orbit close to their host stars this indicates that iron rich inner
planets might not be a nuisance of the solar system but be part of a general
scheme of planet formation. From undifferentiated chondrites it is also known
that the metal to silicate ratio is highly variable which must be ascribed to
pre-planetary fractionation processes. Due to this fractionation most
chondritic parent bodies - most of them originated in the asteroid belt - are
depleted in iron relative to average solar system abundances. The astrophysical
processes leading to metal silicate fractionation in the solar nebula are
essentially unknown. Here, we consider photophoretic forces. As these forces
particularly act on irradiated solids, they might play a significant role for
the composition of planetesimals forming at the inner edge of protoplanetary
discs. Photophoresis can separate high thermal conductivity materials (iron)
from lower thermal conductivity solids (silicate). We suggest that the
silicates are preferentially pushed into the optical thick disk. Subsequent
planetesimal formation at the edge moving outwards leads to metal rich
planetesimals close to the star and metal depleted planetesimals further out in
the nebula.


title:
A causal continuous-time stochastic model for the turbulent energy
  cascade in a helium jet flow

abstract:
  We discuss continuous cascade models and their potential for modelling the
energy dissipation in a turbulent flow. Continuous cascade processes, expressed
in terms of stochastic integrals with respect to L\'evy bases, are examples of
ambit processes. These models are known to reproduce experimentally observed
properties of turbulence: The scaling and self-scaling of the correlators of
the energy dissipation and of the moments of the coarse-grained energy
dissipation. We compare three models: a normal model, a normal inverse Gaussian
model and a stable model. We show that the normal inverse Gaussian model is
superior to both, the normal and the stable model, in terms of reproducing the
distribution of the energy dissipation; and that the normal inverse Gaussian
model is superior to the normal model and competitive with the stable model in
terms of reproducing the self-scaling exponents. Furthermore, we show that the
presented analysis is parsimonious in the sense that the self-scaling exponents
are predicted from the one-point distribution of the energy dissipation, and
that the shape of these distributions is independent of the Reynolds number.


title:
Study of $B_{s}$ ${\to}$ ${\eta}_{c}(J/{\psi})D$ decay with perturbative
  QCD approach

abstract:
  The $W$-exchange process $B_{s}$ ${\to}$ ${\eta}_{c}(J/{\psi})D$ is studied
with the perturbative QCD approach. Three kinds of wave functions for $B_{s}$
meson and two forms of wave functions for charmonium are considered. It is
estimated that branching ratios for $B_{s}$ ${\to}$ ${\eta}_{c}\bar{D}$,
${\eta}_{c}D$, $J/{\psi}\bar{D}$, $J/{\psi}D$ decays are the order of
$10^{-7}$, $10^{-8}$, $10^{-8}$, $10^{-9}$, respectively, where the largest
uncertainty is from wave functions. There is a possibility for measuring these
decay in the near future.


title: Symmetry based parameterizations of the lepton mixing matrix

abstract:
  There are many mixing schemes based upon flavor symmetries that predict a
vanishing $\theta_{13}$. These mixing schemes need corrections or modifications
to account for recent experimental measurements of non-zero $\theta_{13}$. We
propose new parameterizations for the lepton mixing matrix to quantify the
minimal modifications needed in these mixing schemes. The parameterizations can
be factorized in two parts: $U_{0}(a,b)$ and $R(\theta,\phi)$. The first factor
can be viewed as a zeroth order mixing matrix coming from some flavor symmetry.
It reproduces the popular mixing schemes based upon flavor symmetries for
suitable values of $a$ and $b$. The second factor can be interpreted as a
minimal modification to the mixing matrix and is responsible for non zero
$\theta_{13}$, non-maximal $\theta_{23}$ and CP violation. We also find the
experimentally allowed parameter space for the parameters $a$ and $b$ and
compare it with the symmetry based values for these parameters.


title: Dynamical twisting and the b ghost in the pure spinor formalism

abstract:
  After adding an RNS-like fermionic vector \psi^m to the pure spinor
formalism, the non-minimal b ghost takes a simple form similar to the pure
spinor BRST operator. The N=2 superconformal field theory generated by the b
ghost and the BRST current can be interpreted as a "dynamical twisting" of the
RNS formalism where the choice of which spin half \psi^m variables are twisted
into spin 0 and spin 1 variables is determined by the pure spinor variables
that parameterize the coset SO(10)/U(5).


title:
Harmonics suppression effect of the quasi-periodic undulator in SASE
  free-electron-laser

abstract:
  In this paper, the harmonics suppression effect of QPUs in SASE FEL is
investigated. The numerical results show that the harmonics power is reduced by
using QPUs, but the fundamental radiation power also has a pronounced decrease
as the saturation length gets very long. The cases of employing QPUs as parts
of undulators are studied. The calculations show that if the fraction of QPUs
and their offgap are appropriate in an undulator system, the harmonics
radiation could be suppressed remarkably, meanwhile the fundamental saturation
length does not increase too much.


title: Non-locality of the C- and D-theories

abstract:
  Apparent similarities between non-local theories of gravity and the so-called
C-theories are pointed out. It is shown that some simple C-theories can be
mapped exactly into a previously considered type of ghost-free nonlocal
gravity. This may introduce a useful tool to tackle some infinite-order
derivative theories and raises the possibility of describing renormalisable
gravity in a new context of D-theories.


title: Multi-focal spherical media and geodesic lenses in geometrical optics

abstract:
  This paper presents a general approach to designing the isotropic spherical
media with complex spatial structure that provide different types of imaging
for different light rays. It is based on equivalence of the spherical medium
and the corresponding geodesic lens. We use this approach to design multi-focal
gradient- index lenses embedded into an optically homogeneous region and
multi-focal absolute instruments that provide perfect imaging of
three-dimensional domains.


abstract:
  The main object of this paper is to investigate $\lambda$-statistically
quasi-Cauchy sequences. A real valued function $f$ defined on a subset $E$ of
$\textbf{R}$, the set of real numbers, is called $\lambda$-statistically ward
continuous on $E$ if it preserves $\lambda$-statistically quasi-Cauchy
sequences of points in $E$. It turns out that uniform continuity coincides with
$\lambda$-statistically ward continuity on $\lambda$-statistically ward compact
subsets.


title:
Learning from Imprecise and Fuzzy Observations: Data Disambiguation
  through Generalized Loss Minimization

abstract:
  Methods for analyzing or learning from "fuzzy data" have attracted increasing
attention in recent years. In many cases, however, existing methods (for
precise, non-fuzzy data) are extended to the fuzzy case in an ad-hoc manner,
and without carefully considering the interpretation of a fuzzy set when being
used for modeling data. Distinguishing between an ontic and an epistemic
interpretation of fuzzy set-valued data, and focusing on the latter, we argue
that a "fuzzification" of learning algorithms based on an application of the
generic extension principle is not appropriate. In fact, the extension
principle fails to properly exploit the inductive bias underlying statistical
and machine learning methods, although this bias, at least in principle, offers
a means for "disambiguating" the fuzzy data. Alternatively, we therefore
propose a method which is based on the generalization of loss functions in
empirical risk minimization, and which performs model identification and data
disambiguation simultaneously. Elaborating on the fuzzification of specific
types of losses, we establish connections to well-known loss functions in
regression and classification. We compare our approach with related methods and
illustrate its use in logistic regression for binary classification.


title:
Fast, Incremental Inverted Indexing in Main Memory for Web-Scale
  Collections

abstract:
  For text retrieval systems, the assumption that all data structures reside in
main memory is increasingly common. In this context, we present a novel
incremental inverted indexing algorithm for web-scale collections that directly
constructs compressed postings lists in memory. Designing efficient in-memory
algorithms requires understanding modern processor architectures and memory
hierarchies: in this paper, we explore the issue of postings lists contiguity.
Naturally, postings lists that occupy contiguous memory regions are preferred
for retrieval, but maintaining contiguity increases complexity and slows
indexing. On the other hand, allowing discontiguous index segments simplifies
index construction but decreases retrieval performance. Understanding this
tradeoff is our main contribution: We find that co-locating small groups of
inverted list segments yields query evaluation performance that is
statistically indistinguishable from fully-contiguous postings lists. In other
words, it is not necessary to lay out in-memory data structures such that all
postings for a term are contiguous; we can achieve ideal performance with a
relatively small amount of effort.


title:
Symmetry-protected topological phases and orbifolds: Generalized
  Laughlin's argument

abstract:
  We consider non-chiral symmetry-protected topological phases of matter in two
spatial dimensions protected by a discrete symmetry such as $\mathbb{Z}_K$ or
$\mathbb Z_K \times \mathbb Z_K $ symmetry. We argue that modular
invariance/noninvariance of the partition function of the one-dimensional edge
theory can be used to diagnose whether, by adding a suitable potential, the
edge theory can be gapped or not without breaking the symmetry. By taking
bosonic phases described by Chern-Simons K-matrix theories and fermionic phases
relevant to topological superconductors as an example, we demonstrate
explicitly that when the modular invariance is achieved, we can construct an
interaction potential that is consistent with the symmetry and can completely
gap out the edge.


title:
Novel Kinetic 3D MHD Algorithm for High Performance Parallel Computing
  Systems

abstract:
  The impressive progress of the kinetic schemes in the solution of gas
dynamics problems and the development of effective parallel algorithms for
modern high performance parallel computing systems led to the development of
advanced methods for the solution of the magnetohydrodynamics problem in the
important area of plasma physics. The novel feature of the method is the
formulation of the complex Boltzmann-like distribution function of kinetic
method with the implementation of electromagnetic interaction terms. The
numerical method is based on the explicit schemes. Due to logical simplicity
and its efficiency, the algorithm is easily adapted to modern high performance
parallel computer systems including hybrid computing systems with graphic
processors.

categories: physics.plasm-ph math-ph math.MP physics.flu-dyn


title: Fluctuating Mobility Generation and Transport in Glasses

abstract:
  In the context of the random first order transition theory we use an extended
mode coupling theory of the glass transition that includes activated events to
account for spatiotemporal structures in aging and rejuvenating glasses. We
numerically solve fluctuating dynamical equations for mobility and fictive
temperature fields which capture both mobility generation through activated
events and facilitation effects. Upon rejuvenating, a source of high mobility
at a glass surface initiates a growth front of mobility which propagates into
the unstable low mobility region. The speed of the front is consistent with
experiments on the rejuvenation of stable glasses, which "melt" from their
surface.


title: The Jamming point street-lamp in the world of granular media

abstract:
  The Jamming of soft spheres at zero temperature, the J-point, has been
extensively studied both numerically and theoretically and can now be
considered as a safe location in the space of models, where a street lamp has
been lit up. However, a recent work by Ikeda et al, 2013 reveals that, in the
Temperature/Packing fraction parameter space, experiments on colloids are
actually rather far away from the scaling regime illuminated by this lamp. Is
it that the J-point has little to say about real system? What about granular
media? Such a-thermal, frictional, systems are a-priori even further away from
the idealized case of thermal soft spheres. In the past ten years, we have
systematically investigated horizontally shaken grains in the vicinity of the
Jamming transition. We discuss the above issue in the light of very recent
experimental results. First, we demonstrate that the contact network exhibits a
remarkable dynamics, with strong heterogeneities, which are maximum at a
packing fraction phi star, distinct and smaller than the packing fraction phi
dagger, where the average number of contact per particle starts to increase.
The two cross-overs converge at point J in the zero mechanical excitation
limit. Second, a careful analysis of the dynamics on time scales ranging from a
minute fraction of the vibration cycle to several thousands of cycles allows us
to map the behaviors of this shaken granular system onto those observed for
thermal soft spheres and demonstrate that some light of the J-point street-lamp
indeed reaches the granular universe.


title:
Ground state solution for a problem with mean curvature operator in
  Minkowski space

abstract:
  In this paper we prove the existence of a radial ground state solution for a
quasilinear problem involving the mean curvature operator in Minkowski space.


title:
Zero-energy states of graphene triangular quantum dots in a magnetic
  field

abstract:
  We present a tight-binding theory of triangular graphene quantum dots (TGQD)
with zigzag edge and broken sublattice symmetry in external magnetic field. The
lateral size quantization opens an energy gap and broken sublattice symmetry
results in a shell of degenerate states at the Fermi level. We derive a
semi-analytical form for zero-energy states in a magnetic field and show that
the shell remains degenerate in a magnetic field, in analogy to the 0th Landau
level of bulk graphene. The magnetic field closes the energy gap and leads to
the crossing of valence and conduction states with the zero-energy states,
modulating the degeneracy of the shell. The closing of the gap with increasing
magnetic field is present in all graphene quantum dot structures investigated
irrespective of shape and edge termination.


title: Design of Magnetic Textures of Ad-Nanocorrals with an Extra Adatom

abstract:
  It is shown that in antiferromagnetic open or closed corrals of magnetic
adatoms grown on surfaces, the attachment of a single extra adatom anywhere in
the corral impacts on the geometrical topology of the nanosystem and generates
complex magnetic structures when a magnetic field is applied or a magnetic
coupling to a ferromagnetic substrate exists. The spin configuration of the
corral can be tuned to a non-planar state or a planar non-collinear or
ferrimagnetic state by adjusting its number of sites, the location of the extra
adatom or the strength of the coupling to the ferromagnetic substrate. This
shows the possibility to generate non-trivial magnetic textures with atom by
atom engineering anywhere in the corral and not only at the edges.


title:
Steady free fall of one-dimensional bodies in a hyperviscous fluid at
  low Reynolds number

abstract:
  The paper is devoted to the study of the motion of one-dimensional rigid
bodies during a free fall in a quasi-Newtonian hyperviscous fluid at low
Reynolds number. We show the existence of a steady solution and furnish
sufficient conditions on the geometry of the body in order to get purely
translational motions. Such conditions are based on a generalized version of
the so-called Reciprocal Theorem for fluids.


title:
Fast computation of MadGraph amplitudes on graphics processing unit
  (GPU)

abstract:
  Continuing our previous studies on QED and QCD processes, we use the graphics
processing unit (GPU) for fast calculations of helicity amplitudes for general
Standard Model (SM) processes. Additional HEGET codes to handle all SM
interactions are introduced, as well assthe program MG2CUDA that converts
arbitrary MadGraph generated HELAS amplitudess(FORTRAN) into HEGET codes in
CUDA. We test all the codes by comparing amplitudes and cross sections for
multi-jet srocesses at the LHC associated with production of single and double
weak bosonss a top-quark pair, Higgs boson plus a weak boson or a top-quark
pair, and multisle Higgs bosons via weak-boson fusion, where all the heavy
particles are allowes to decay into light quarks and leptons with full spin
correlations. All the helicity amplitudes computed by HEGET are found to agree
with those comsuted by HELAS within the expected numerical accuracy, and the
cross sections obsained by gBASES, a GPU version of the Monte Carlo integration
program, agree wish those obtained by BASES (FORTRAN), as well as those
obtained by MadGraph. The performance of GPU was over a factor of 10 faster
than CPU for all processes except those with the highest number of jets.


title:
Joint likelihood calculation for intervention and observational data
  from a Gaussian Bayesian network

abstract:
  Methodological development for the inference of gene regulatory networks from
transcriptomic data is an active and important research area. Several
approaches have been proposed to infer relationships among genes from
observational steady-state expression data alone, mainly based on the use of
graphical Gaussian models. However, these methods rely on the estimation of
partial correlations and are only able to provide undirected graphs that cannot
highlight causal relationships among genes. A major upcoming challenge is to
jointly analyze observational transcriptomic data and intervention data
obtained by performing knock-out or knock-down experiments in order to uncover
causal gene regulatory relationships. To this end, in this technical note we
present an explicit formula for the likelihood function for any complex
intervention design in the context of Gaussian Bayesian networks, as well as
its analytical maximization. This allows a direct calculation of the causal
effects for known graph structure. We also show how to obtain the Fisher
information in this context, which will be extremely useful for the choice of
optimal intervention designs in the future.


title: A geometric setting for quantum osp(1|2)

abstract:
  A geometric categorification is given for arbitrary-large-finite-dimensional
quotients of quantum osp(1|2) and the tensor product of its simple modules. The
modified quantum osp(1|2) of Clark-Wang, a new version in this paper and the
modified quantum sl(2) are isomorphic to each other over a field containing
Q(v) and a root of -1.


title: New hybrid distributed voting algorithm

abstract:
  Increasing data volumes requires additional rating techniques. Reputation
systems are the subject of much research. There are various techniques to rate
content that facilitate the search of quality content. Page rank, citation
index and votes from users are some rating examples. In the article I focus on
decentralized vote systems. The article reviews several distributed vote
designs. I list the distributed vote requirements. A new hybrid algorithm is
proposed which operates in the structured overlay P2P DHT Kademlia network.


title: Field-dependent BRST transformations in Yang-Mills theory

abstract:
  We find an explicit form for the Jacobian of arbitrary field-dependent BRST
transformations in Yang-Mills theory. For the functional-integral
representation of the (gauge-fixed) Yang-Mills vacuum functional, such
transformations merely amount to a precise change in the gauge-fixing
functional. This proves the independence of the vacuum functional under any
field-dependent BRST transformation. We also give a formula for the
transformation parameter functional which generates a prescribed change of
gauge and evaluate it for connecting two arbitrary R_xi gauges.


title:
Absolute Continuity of the Laws of Perturbed Diffusion Processes and
  Perturbed Reflected Diffusion Processes

abstract:
  In this paper, we prove that the laws of perturbed diffusion processes and
perturbed reflected diffusion processes are absolutely continuous with respect
to the Lebesgue measure. The main tool we use is the Malliavin calculus.


title:
Co2 FeAl thin films grown on MgO substrates: Correlation between static,
  dynamic and structural properties

abstract:
  Co2FeAl (CFA) thin films with thickness varying from 10 nm to 115 nm have
been deposited on MgO(001) substrates by magnetron sputtering and then capped
by Ta or Cr layer. X-rays diffraction (XRD) revealed that the cubic $[001]$ CFA
axis is normal to the substrate and that all the CFA films exhibit full
epitaxial growth. The chemical order varies from the $B2$ phase to the $A2$
phase when decreasing the thickness. Magneto-optical Kerr effect (MOKE) and
vibrating sample magnetometer measurements show that, depending on the field
orientation, one or two-step switchings occur. Moreover, the films present a
quadratic MOKE signal increasing with the CFA thickness, due to the increasing
chemical order. Ferromagnetic resonance, MOKE transverse bias initial inverse
susceptibility and torque (TBIIST) measurements reveal that the in-plane
anisotropy results from the superposition of a uniaxial and of a fourfold
symmetry term. The fourfold anisotropy is in accord with the crystal structure
of the samples and is correlated to the biaxial strain and to the chemical
order present in the films. In addition, a large negative perpendicular
uniaxial anisotropy is observed. Frequency and angular dependences of the FMR
linewidth show two magnon scattering and mosaicity contributions, which depend
on the CFA thickness. A Gilbert damping coefficient as low as 0.0011 is found.


title: On the convergence of the Gaver-Stehfest algorithm

abstract:
  The Gaver-Stehfest algorithm for numerical inversion of Laplace transform was
developed in the late 1960s. Due to its simplicity and good performance it is
becoming increasingly more popular in such diverse areas as Geophysics,
Operations Research and Economics, Financial and Actuarial Mathematics,
Computational Physics and Chemistry. Despite the large number of applications
and numerical studies, this method has never been rigorously investigated. In
particular, it is not known whether the Gaver-Stehfest approximations converge
and what is the rate of convergence. In this paper we answer the first of these
two questions: We prove that the Gaver-Stehfest approximations converge for
functions of bounded variation and functions satisfying an analogue of Dini
criterion.


title:
Preconditioning filter bank decompositions using structured normalized
  tight frames

abstract:
  We turn a given filter bank into a filtering scheme that provides perfect
reconstruction, synthesis is the adjoint of the analysis part (so-called
unitary filter banks), all filters have equal norm, and the essential features
of the original filter bank are preserved. Unitary filter banks providing
perfect reconstruction are induced by tight generalized frames, which enable
signal decomposition using a set of linear operators. If, in addition, frame
elements have equal norm, then the signal energy is spread through the various
filter bank channels in some uniform fashion, which is often more suitable for
further signal processing. We start with a given generalized frame whose
elements allow for fast matrix vector multiplication, as for instance,
convolution operators, and compute a normalized tight frame, for which signal
analysis and synthesis still preserve those fast algorithmic schemes.


title:
The probability of drawing intersections: extending the hypergeometric
  distribution

abstract:
  The wide availability of biological data at the genome-scale and across
multiple variables has resulted in statistical questions regarding the
enrichment or depletion of the number of discrete objects (e.g. genes)
identified in individual experiments. Here, I consider the problem of inferring
enrichment or depletion when drawing independently, and without replacement,
from two or more separate urns in which the same $n$ distinct categories of
objects exist. The statistic of interest is the size of the intersection of
object categories. I derive a probability mass function describing the
distribution of intersection sizes when sampling from N urns and show that this
distribution follows the classic hypergeometric distribution when N = 2. I
apply the theory to the intersection of genes belonging to a set of traits in
three different vertebrate species illustrating that the use of P-values from
one-tailed enrichment tests enables accurate clustering of related traits, yet
this is not possible when relying on intersection sizes alone. In addition,
intersection distributions provide a means to test for co-localization of
objects in images when using discretized data, allowing co-localization tests
in more than two channels. Finally, I show how to extend the problem to
variable numbers of objects belonging to each category, and discuss how to make
further progress in this direction. The distribution functions are implemented
and freely available in the R package 'hint'.


title:
Generalized Deam-Edwards Approach to the Statistical Mechanics of
  Randomly Crosslinked Systems

abstract:
  We address the statistical mechanics of randomly and permanently crosslinked
networks. We develop a theoretical framework (vulcanization theory) which can
be used to systematically analyze the correlation between the statistical
properties of random networks and their histories of formation. Generalizing
the original idea of Deam and Edwards, we consider an instantaneous
crosslinking process, where all crosslinkers (modeled as Gaussian springs) are
introduced randomly at once in an equilibrium liquid state, referred to as the
preparation state. The probability that two functional sites are crosslinked by
a spring exponentially decreases with their distance squared. After formally
averaging over network connectivity, we obtained an effective theory with all
degrees of freedom replicated 1 + n times. Two thermodynamic ensembles, the
preparation ensemble and the measurement ensemble, naturally appear in this
theory. The former describes the thermodynamic fluctuations in the state of
preparation, while the latter describes the thermodynamic fluctuations in the
state of measurement. We classify various correlation functions and discuss
their physical significances. In particular, the memory correlation functions
characterize how the properties of networks depend on their history of
formation, and are the hallmark properties of all randomly crosslinked
materials. We clarify the essential difference between our approach and that of
Deam-Edwards, discuss the saddle-point order parameters and its physical
significance. Finally we also discuss the connection between saddle-point
approximation of vulcanization theory, and the classical theory of rubber
elasticity as well as the neo-classical theory of nematic elastomers.


title:
Development of a new generation of micropattern gaseous detectors for
  high energy physics, astrophysics and environmental applications

abstract:
  We have developed a cost effective technology for manufacturing various
layouts of micropattern gaseous detectors for a wide range of applications.
Such devices feature resistive electrodes interfaced to a network of thin
readout strips/electrodes. The following three examples of such innovative
designs and their applications will be presented: a prototype of a novel
double-phase LAr detector with a CsI photocathode immersed inside the LAr, a
CsI-RICH detector prototype for ALICE upgrade and GEM-like sensors for
environmental safety/security applications.


title: The Dirichlet-to-Neumann operator via hidden compactness

abstract:
  We show that to each symmetric elliptic operator of the form \[ \mathcal{A} =
- \sum \partial_k \, a_{kl} \, \partial_l + c \] on a bounded Lipschitz domain
$\Omega \subset \mathbb{R}^d$ one can associate a self-adjoint
Dirichlet-to-Neumann operator on $L_2(\partial \Omega)$, which may be
multi-valued if 0 is in the Dirichlet spectrum of $\mathcal{A}$. To overcome
the lack of coerciveness in this case, we employ a new version of the
Lax--Milgram lemma based on an indirect ellipticity property that we call
hidden compactness. We then establish uniform resolvent convergence of a
sequence of Dirichlet-to-Neumann operators whenever their coefficients converge
uniformly and the second-order limit operator in $L_2(\Omega)$ has the unique
continuation property. We also consider semigroup convergence.


title: Isocapacity Estimates for Hessian Operators

abstract:
  Through a new powerful potential-theoretic analysis, this paper is devoted to
discovering the geometrically equivalent isocapacity forms of Chou-Wang's
Sobolev type inequality and Tian-Wang's Moser-Trudinger type inequality for the
fully nonlinear $1\leq k\leq n/2$ Hessian operators.


title:
A note on the series representation for the density of the supremum of a
  stable process

abstract:
  An absolutely convergent double series representation for the density of the
supremum of $\alpha$-stable Levy process is given in [3, Theorem 2] for almost
all irrational $\alpha$. This result cannot be made stronger in the following
sense: the series does not converge absolutely when $\alpha$ belongs to a
certain subset of irrational numbers of Lebesgue measure zero (see [6, Theorem
2]). Our main result in this note shows that for every irrational $\alpha$
there is a way to rearrange the terms of the double series, so that it
converges to the density of the supremum. We show how one can establish this
stronger result by introducing a simple yet non-trivial modification in the
original proof of [3,Theorem 2].


title: On Torus Homeomorphisms Semiconjugate to irrational Rotations

abstract:
  In the context of the Franks-Misiurewicz Conjecture, we study homeomorphisms
of the two-torus semiconjugate to an irrational rotation of the circle. As a
special case, this conjecture asserts uniqueness of the rotation vector in this
class of systems. We first characterise these maps by the existence of an
invariant foliation by essential annular continua (essential subcontinua of the
torus whose complement is an open annulus) which are permuted with irrational
combinatorics. This result places the considered class close to skew products
over irrational rotations. Generalising a well-known result of M. Herman on
forced circle homeomorphisms, we provide a criterion, in terms of topological
properties of the annular continua, for the uniqueness of the rotation vector.
As a byproduct, we obtain a simple proof for the uniqueness of the rotation
vector on decomposable invariant annular continua with empty interior. In
addition, we collect a number of observations on the topology and rotation
intervals of invariant annular continua with empty interior.


title: The excursion set approach in non-Gaussian random fields

abstract:
  Insight into a number of interesting questions in cosmology can be obtained
from the first crossing distributions of physically motivated barriers by
random walks with correlated steps. We write the first crossing distribution as
a formal series, ordered by the number of times a walk upcrosses the barrier.
Since the fraction of walks with many upcrossings is negligible if the walk has
not taken many steps, the leading order term in this series is the most
relevant for understanding the massive objects of most interest in cosmology.
This first term only requires knowledge of the bivariate distribution of the
walk height and slope, and provides an excellent approximation to the first
crossing distribution for all barriers and smoothing filters of current
interest. We show that this simplicity survives when extending the approach to
the case of non-Gaussian random fields. For non-Gaussian fields which are
obtained by deterministic transformations of a Gaussian, the first crossing
distribution is simply related to that for Gaussian walks crossing a suitably
rescaled barrier. Our analysis shows that this is a useful way to think of the
generic case as well. Although our study is motivated by the possibility that
the primordial fluctuation field was non-Gaussian, our results are general. In
particular, they do not assume the non-Gaussianity is small, so they may be
viewed as the solution to an excursion set analysis of the late-time, nonlinear
fluctuation field rather than the initial one. They are also useful for models
in which the barrier height is determined by quantities other than the initial
density, since most other physically motivated variables (such as the shear)
are usually stochastic and non-Gaussian. We use the Lognormal transformation to
illustrate some of our arguments.


title: Asian options and meromorphic Levy processes

abstract:
  One method to compute the price of an arithmetic Asian option in a Levy
driven model is based on the exponential functional of the underlying Levy
process: If we know the distribution of the exponential functional, we can
calculate the price of the Asian option via the inverse Laplace transform. In
this paper we consider pricing Asian options in a model driven by a general
meromorphic Levy process. We prove that the exponential functional is equal in
distribution to an infinite product of indepedent beta random variables, and
its Mellin transform can be expressed as an infinite product of gamma
functions. We show that these results lead to an efficient algorithm for
computing the price of the Asian option via the inverse Mellin-Laplace
transform, and we compare this method with some other techniques.


title:
A note on the limiting mean distribution of singular values for products
  of two Wishart random matrices

abstract:
  The product of M complex random Gaussian matrices of size N has recently been
studied by Akemann, Kieburg and Wei. They showed that, for fixed M and N, the
joint probability distribution for the squared singular values of the product
matrix forms a determinantal point process with a correlation kernel determined
by certain biorthogonal polynomials that can be explicitly constructed. We find
that, in the case M=2, the relevant biorthogonal polynomials are actually
special cases of multiple orthogonal polynomials associated with Macdonald
functions (modified Bessel functions of the second kind) which was first
introduced by Van Assche and Yakubovich. With known results on asymptotic zero
distribution of these polynomials and general theory on multiple orthogonal
polynomial ensembles, it is then easy to obtain an explicit expression for the
distribution of squared singular values for the product of two complex random
Gaussian matrices in the limit of large matrix dimensions.


title:
Arterial stiffening provides sufficient explanation for primary
  hypertension

abstract:
  Hypertension is one of the most common age-related chronic diseases and by
predisposing individuals for heart failure, stroke and kidney disease, it is a
major source of morbidity and mortality. Its etiology remains enigmatic despite
intense research efforts over many decades. By use of empirically
well-constrained computer models describing the coupled function of the
baroreceptor reflex and mechanics of the circulatory system, we demonstrate
quantitatively that arterial stiffening seems sufficient to explain age-related
emergence of hypertension. Specifically, the empirically observed chronic
changes in pulse pressure with age, and the impaired capacity of hypertensive
individuals to regulate short-term changes in blood pressure, arise as emergent
properties of the integrated system. Results are consistent with available
experimental data from chemical and surgical manipulation of the
cardio-vascular system. In contrast to widely held opinions, the results
suggest that primary hypertension can be attributed to a mechanogenic etiology
without challenging current conceptions of renal and sympathetic nervous system
function. The results support the view that a major target for treating chronic
hypertension in the elderly is the reestablishment of a proper baroreflex
response.


title: New relations for the old triangle

abstract:
  In this note we show that in addition to two integers forming a Pythagorean
triple, there also exist two irrational numbers in terms of which this
Pythagorean triple can also be obtained. We also put forward a relation between
these two pairs and the hypotenuse of a Pythagorean triangle.


title:
Hyperbolic monodromy groups for the hypergeometric equation and Cartan
  involutions

abstract:
  We give a criterion which ensures that a group generated by Cartan
involutions in the automorph group of a rational quadratic form of signature
(n-1,1) is "thin", namely it is of infinite index in the latter. It is based on
a graph defined on the integral Cartan root vectors, as well as Vinberg's
theory of hyperbolic reflection groups. The criterion is shown to be robust for
showing that many hyperbolic hypergeometric groups for n_F_(n-1) are thin.


title: BPS Black Holes in AdS4 from M-theory

abstract:
  We study supersymmetric black holes in $AdS_4$ in the framework of four
dimensional gauged $\N=2$ supergravity coupled to hypermultiplets. We derive
the flow equations for a general electrically gauged theory where the gauge
group is Abelian and, restricting them to the fixed points, we derive the
gauged supergravity analogue of the attractor equations for theories coupled to
hypermultiplets. The particular models we analyze are consistent truncations of
M-theory on certain Sasaki-Einstein seven-manifolds. We study the space of
horizon solutions of the form $AdS_2\times \Sigma_g$ with both electric and
magnetic charges and find a four-dimensional solution space when the theory
arises from a reduction on $Q^{111}$. For other $SE_7$ reductions, the
solutions space is a subspace of this. We construct explicit examples of
spherically symmetric black holes numerically.


title: Semiclassical hypoelliptic estimates with a big loss of derivatives

abstract:
  We study the pseudospectral properties of general pseudodifferential
operators around a doubly characteristic point and provide necessary and
sufficient conditions for semiclassical hypoelliptic a priori estimates with a
big loss of derivatives to hold.


title: Order of convexity of Integral Transforms and Duality

abstract:
  Recently, Ali et al defined the class $\mathcal{W}_{\beta}(\alpha, \gamma)$
consisting of functions $f$ which satisfy $$\Re
e^{i\phi}\left((1-\alpha+2\gamma)\frac{f(z)}{z}+(\alpha-2\gamma)f'(z)+\gamma
zf''(z)-\beta\right)>0,$$ for all $z\in E=\left\{z : |z|<1\right\}$ and for
$\alpha, \gamma\geq0$ and $\beta<1$, $\phi\in \mathbb{R}$ (the set of reals).
For $f\in{\mathcal{W}_{\beta}(\alpha, \gamma)}$, they discussed the convexity
of the integral transform
$$V_{\lambda}(f)(z):=\int_{0}^{1}\lambda(t)\frac{f(tz)}{t}dt,$$ where $\lambda$
is a non-negative real-valued integrable function satisfying the condition
$\displaystyle\int_{0}^{1}\lambda(t)dt=1$. The aim of present paper is to find
conditions on $\lambda(t)$ such that $V_{\lambda}(f)$ is convex of order
$\delta$ ($0\leq\delta\leq1/2$) whenever $f\in{\mathcal{W}}_{\beta}(\alpha,
\gamma)$. As applications, we study various choices of $\lambda(t)$, related to
classical integral transforms.


title: Transmission Eigenvalues in One Dimension

abstract:
  We show how to locate all the transmission eigenvalues for a one dimensional
constant index of refraction on an interval.


title:
Finite reflection groups and the Dunkl-Laplace differential-difference
  operators in conformal geometry

abstract:
  For a finite reflection subgroup $G\leq O(n+1,1,\mR)$ of the conformal group
of the sphere with standard conformal structure $(S^n,[g_0])$, we geometrically
derive differential-difference Dunkl version of the series of conformally
invariant differential operators with symbols given by powers of Laplace
operator. The construction can be regarded as a deformation of the
Fefferman-Graham ambient metric construction of GJMS operators.


title:
Increasing Smart Meter Privacy Through Energy Harvesting and Storage
  Devices

abstract:
  Smart meters are key elements for the operation of smart grids. By providing
near realtime information on the energy consumption of individual users, smart
meters increase the efficiency in generation, distribution and storage of
energy in a smart grid. The ability of the utility provider to track users
energy consumption inevitably leads to important threats to privacy. In this
paper, privacy in a smart metering system is studied from an information
theoretic perspective in the presence of energy harvesting and storage units.
It is shown that energy harvesting provides increased privacy by diversifying
the energy source, while a storage device can be used to increase both the
energy efficiency and the privacy of the user. For given input load and energy
harvesting rates, it is shown that there exists a trade-off between the
information leakage rate, which is used to measure the privacy of the user, and
the wasted energy rate, which is a measure of the energy-efficiency. The impact
of the energy harvesting rate and the size of the storage device on this
trade-off is also studied.


title: Active Fluctuation Symmetries

abstract:
  In contrast with the understanding of fluctuation symmetries for entropy
production, similar ideas applied to the time-symmetric fluctuation sector have
been less explored. Here we give detailed derivations of time-symmetric
fluctuation symmetries in boundary driven particle systems such as the open
Kawasaki lattice gas and the zero range model. As a measure of time-symmetric
dynamical activity we take the difference $(N_1 - N_L)/T$ in the number of
particles entering or leaving the system at the left versus the right edge of
the system over time $T$. We show that this quantity satisfies a fluctuation
symmetry from which we derive a new Green-Kubo type relation. It will follow
then that the system is more active at the edge connected to the particle
reservoir with the largest chemical potential. We also apply these exact
relations derived for stochastic particle models to a deterministic case, the
spinning Lorentz gas, where the symmetry relation for the activity is checked
numerically.


title:
New results on the cp rank and related properties of
  co(mpletely)positive matrices

abstract:
  Copositive and completely positive matrices play an increasingly important
role in Applied Mathematics, namely as a key concept for approximating NP-hard
optimization problems. The cone of copositive matrices of a given order and the
cone of completely positive matrices of the same order are dual to each other
with respect to the standard scalar product on the space of symmetric matrices.
This paper establishes some new relations between orthogonal pairs of such
matrices lying on the boundary of either cone. As a consequence, we can
establish an improvement on the upper bound of the cp-rank of completely
positive matrices of general order, and a further improvement for such matrices
of order six.


title: Quantization of Black Holes entropy and its cosmological consequences

abstract:
  Starting from a quantization relation for primordial extremal black holes
with electric and magnetic charges, it is shown that their entropy is
quantized. Furthermore the energy levels spacing for such black holes is
derived as a function of the level number $n$, appearing in the quantization
relation. Some interesting cosmological consequences are presented for small
values of $n$. By producing a mismatch between the mass and the charge the
black hole temperature is derived and its behavior investigated. Finally
extending the quantum relation to Schwarzschild black holes their temperature
is found to be in agreement with the Hawking temperature and a simple
interpretation of the microscopic degrees of freedom of the black holes is
given.


title: Cosmological Evolution for Dark Energy Models in f(T) Gravity

abstract:
  In this paper, we investigate the behavior of equation of state parameter and
energy density for dark energy in the framework of f(T) gravity. For this
purpose, we use anisotropic LRS Bianchi type I universe model. The behavior of
accelerating universe is discussed for some well-known f(T) models. It is found
that the universe takes a transition between phantom and non-phantom phases for
f(T) models except exponential and logarithmic models. We conclude that our
results are relativity analogous to the results of FRW universe.


title:
Tachyon Warm-Logamediate Inflationary Universe Model in High Dissipative
  Regime

abstract:
  In the present work, we study warm tachyon inflation model in the context of
"logamediate inflation" where the cosmological scale factor expands as
$a=a_0\exp(A[\ln t]^{\lambda})$. The characteristics of this model in slow-roll
approximation are presented in two cases: 1- Dissipative parameter $\Gamma$ is
a function of tachyon field $\phi$. 2- $\Gamma$ is a constant parameter. The
level of non-Gaussianity of this model is found for these two cases. Scalar and
tensor perturbations for this scenario are presented. The parameters appearing
in our model are constrained by recent observational data (WMAP7).
Harrison-Zeldovich spectrum, i.e. $n_s=1,$ is approximately obtained for large
values of $\lambda$ (i.e. $\lambda\simeq 50$)and normal value of number of
e-folds, i.e. $N\simeq 60$. On the other hand, the scale invariant spectrum
(Harrison-Zeldovich spectrum) is given by using two parameters in our model.
For intermediate inflation, where the cosmological scale factor expands as
$a=a_0\exp(A t^{f}),$ this spectrum has been exactly obtained using one
parameter, i.e. $f=2/3$ \cite{2-n}.


title: Delusions of Success: Comment on Dan Lovallo and Daniel Kahneman

abstract:
  Dan Lovallo and Daniel Kahneman must be commended for their clear
identification of causes and cures to the planning fallacy in "Delusions of
Success: How Optimism Undermines Executives' Decisions" (HBR July 2003). Their
look at overoptimism, anchoring, competitor neglect, and the outside view in
forecasting is highly useful to executives and forecasters. However, Lovallo
and Kahneman underrate one source of bias in forecasting - the deliberate
"cooking" of forecasts to get ventures started.


title: The logical foundations of Gibbs' paradox in classical thermodynamics

abstract:
  The analysis of the arguments within the limits of the classical
thermodynamics that lead to the Gibbs paradox was made. Features of
preconditions used in the derivation of the entropy of mixing of ideal gases
that caused the appearance of paradox were established. It was shown that the
Gibbs paradox has not connection with the assumption of discrete differences
between the parameters of different gases.


title:
Realistic Simulations of Stellar Surface Convection with ANTARES: I.
  Boundary Conditions and Model Relaxation

abstract:
  We have implemented open boundary conditions into the ANTARES code to
increase the realism of our simulations of stellar surface convection. Even
though we greatly benefit from the high accuracy of our fifth order numerical
scheme (WENO5), the broader stencils needed for the numerical scheme complicate
the implementation of boundary conditions. We show that the effective
temperature of a numerical simulation cannot be changed by corrections at the
lower boundary since the thermal stratification does only change on the
Kelvin-Helmholtz time scale. Except for very shallow models, this time scale
cannot be covered by multidimensional simulations due to the enormous
computational requirements. We demonstrate to what extent numerical simulations
of stellar surface convection are sensitive to the initial conditions and the
boundary conditions. An ill-conceived choice of parameters for the boundary
conditions can have a severe impact. Numerical simulations of stellar surface
convection will only be (physically) meaningful and realistic if the initial
model, the extent and position of the simulation box, and the parameters from
the boundary conditions are chosen adequately.


title:
On modules over group rings of groups with restrictions on the system of
  all proper subgroups

abstract:
  We consider the class $\mathfrak M$ of $\bf R$--modules where $\bf R$ is an
associative ring. Let $A$ be a module over a group ring $\bf R$$G$ where $G$ is
a group and let $\mathfrak L(G)$ be a set of all proper subgroups of $G$ such
that if $H \in \mathfrak L(G)$ then $A/C_{A}(H)$ belongs to $\mathfrak M$. We
study an $\bf R$$G$--module $A$ such that $G \not = G'$, $C_{G}(A) = 1$,
$A/C_{A}(G) \not \in \mathfrak M$, and $\mathfrak M$ is one of the classes:
artinian $\bf R$--modules, minimax $\bf R$--modules, finite $\bf R$--modules.
We consider the cases: 1) $\mathfrak M$ is a class of all artinian $\bf
R$--modules, $\bf R$ is either a ring of integers or a ring of $p$--adic
integers; 2) $\mathfrak M$ is a class of all minimax $\bf R$--modules, $\bf R$
is a ring of integers, G is a locally soluble group; 3) $\mathfrak M$ is a
class of all finite $\bf R$--modules, $\bf R$ is an associative ring. In these
cases we prove that $G$ is isomorphic to a quasi--cyclic $q$--group for some
prime $q$.


title:
Dependence of spin pumping spin Hall effect measurements on layer
  thicknesses and stacking order

abstract:
  Voltages generated from inverse spin Hall and anisotropic magneto-resistance
effects via spin pumping in ferromagnetic (F)/non-magnetic (N) bilayers are
investigated by means of a broadband ferromagnetic resonance approach. Varying
the non-magnetic layer thickness enables the determination of the spin
diffusion length in Pd of 5.5 +/- 0.5 nm. We also observe a systematic change
of the voltage lineshape when reversing the stacking order of the F/N bilayer,
which is qualitatively consistent with expectations from spin Hall effects.
However, even after independent calibration of the precession angle, systematic
quantitative discrepancies in analyzing the data with spin Hall effects remain.


title: Some forms of exceptional Lie algebras

abstract:
  Some forms of Lie algebras of types E_6, E_7, and E_8 are constructed using
the exterior cube of a rank 9 finitely generated projective module.


title: Exotics Searches at ATLAS

abstract:
  An overview of recent searches for exotic signatures using the ATLAS detector
at the LHC is given. The results presented use data collected at center-of-mass
energies of $\sqrt{s}$ = 7 TeV and $\sqrt{s}$ = 8 TeV, for datasets
corresponding to a variety of integrated luminosities. Resonance searches using
leptons, photons, missing transverse energy, and jets are performed, as well as
searches requiring custom jet and track reconstruction. No deviations from
Standard Model expectations are observed.


title:
Complete next-to-leading-order study on the yield and polarization of
  Upsilon(1S,2S,3S) at the Tevatron and LHC

abstract:
  Based on nonrelativistic QCD factorization scheme, we present the first
complete next-to-leading order study on the yield and polarization of
Upsilon(1S,2S,3S) hadroproduction. By using the color-octet long-distance
matrix elements obtained from fits of the experimental measurements on Upsilon
yield and polarization at the Tevatron and LHC, our results can explain the
measurements on the yield very well, and for the polarizations of
Upsilon(1S,2S,3S), they are in (good, good, bad) agreement with recent CMS
measurement, but still have some distance from the CDF measurement.


title: Noise-Protected Gate for Six-Electron Double-Dot Qubits

abstract:
  Singlet-triplet spin qubits in six-electron double quantum dots, in moderate
magnetic fields, can show superior immunity to charge noise. This immunity
results from the symmetry of orbitals in the second energy shell of circular
quantum dots: singlet and triplet states in this shell have identical charge
distributions. Our phase-gate simulations, which include $1/f$ charge noise
from fluctuating traps, show that this symmetry is most effectively exploited
if the gate operation switches rapidly between sweet spots deep in the (3,3)
and (4,2) charge stability regions; fidelities very close to one are predicted
if subnanosecond switching can be performed.


title: Multi-Sided Boundary Labeling

abstract:
  In the Boundary Labeling problem, we are given a set of $n$ points, referred
to as sites, inside an axis-parallel rectangle $R$, and a set of $n$ pairwise
disjoint rectangular labels that are attached to $R$ from the outside. The task
is to connect the sites to the labels by non-intersecting rectilinear paths,
so-called leaders, with at most one bend.
  In this paper, we study the Multi-Sided Boundary Labeling problem, with
labels lying on at least two sides of the enclosing rectangle. We present a
polynomial-time algorithm that computes a crossing-free leader layout if one
exists. So far, such an algorithm has only been known for the cases in which
labels lie on one side or on two opposite sides of $R$ (here a crossing-free
solution always exists). The case where labels may lie on adjacent sides is
more difficult. We present efficient algorithms for testing the existence of a
crossing-free leader layout that labels all sites and also for maximizing the
number of labeled sites in a crossing-free leader layout. For two-sided
boundary labeling with adjacent sides, we further show how to minimize the
total leader length in a crossing-free layout.


title: Marginal AMP Chain Graphs

abstract:
  We present a new family of models that is based on graphs that may have
undirected, directed and bidirected edges. We name these new models marginal
AMP (MAMP) chain graphs because each of them is Markov equivalent to some AMP
chain graph under marginalization of some of its nodes. However, MAMP chain
graphs do not only subsume AMP chain graphs but also multivariate regression
chain graphs. We describe global and pairwise Markov properties for MAMP chain
graphs and prove their equivalence for compositional graphoids. We also
characterize when two MAMP chain graphs are Markov equivalent.
  For Gaussian probability distributions, we also show that every MAMP chain
graph is Markov equivalent to some directed and acyclic graph with
deterministic nodes under marginalization and conditioning on some of its
nodes. This is important because it implies that the independence model
represented by a MAMP chain graph can be accounted for by some data generating
process that is partially observed and has selection bias. Finally, we modify
MAMP chain graphs so that they are closed under marginalization for Gaussian
probability distributions. This is a desirable feature because it guarantees
parsimonious models under marginalization.


title:
The transition to a layered phase in the anisotropic five-dimensional
  SU(2) Yang-Mills theory

abstract:
  We extend to large lattices the work of a previous investigation of the phase
diagram of the anisotropic five-dimensional SU(2) Yang-Mills model using Monte
Carlo simulations in the regime where the lattice spacing in the fifth
dimension is larger than in the other four dimensions. We find a first order
phase transition between the confining and deconfining phase at the anisotropic
parameter point $\beta_4=2.60$ which was previously claimed to be the critical
point at which the order of the transition changes from first to second. We
conclude that large lattices are required to establish the first order nature
of this line of transitions and consequently that the scenario of dimensional
reduction of the five-dimensional theory to a continuum four-dimensional theory
via the existence of the so-called "layer phase" is unpromising.


title:
Statistical Distribution of the Vacuum Energy Density in Racetrack
  K\"ahler Uplift Models in String Theory

abstract:
  We study a racetrack model in the presence of the leading alpha'-correction
in flux compactification in Type IIB string theory, for the purpose of getting
conceivable de-Sitter vacua in the large compactified volume approximation.
Unlike the K\"ahler Uplift model studied previously, the alpha'-correction is
more controllable for the meta-stable de-Sitter vacua in the racetrack case
since the constraint on the compactified volume size is very much relaxed. We
find that the vacuum energy density \Lambda for de-Sitter vacua approaches zero
exponentially as the volume grows. We also analyze properties of the
probability distribution of \Lambda in this class of models. As in other cases
studied earlier, the probability distribution again peaks sharply at \Lambda=0.
We also study the Racetrack K\"ahler Uplift model in the Swiss-Cheese type
model.


title:
Long-range angular correlations by strong color fields in hadronic
  collisions

abstract:
  I present an overview of the ridge phenomenon in proton-proton and
proton-lead collisions. This novel collimation between rapidity separated
hadron pairs is a consequence of non-linear gluon dynamics within the small-x
wave-function of the colliding hadrons.


title: Evidence for nonlocal electrodynamics in planar Josephson junctions

abstract:
  We study temperature dependence of the critical current modulation Ic(H) for
two types of planar Josephson junctions: a low-Tc Nb/CuNi/Nb and a high-Tc
YBa2Cu3O7 bicrystal grain-boundary junction. At low T both junctions exhibit a
conventional behavior, described by the local sine-Gordon equation. However, at
elevated T the behavior becomes qualitatively different: the Ic(H) modulation
field deltaH becomes almost T-independent and neither deltaH nor the critical
field for penetration of Josephson vortices vanish at Tc. Such an unusual
behavior is in good agreement with theoretical predictions for junctions with
nonlocal electrodynamics. We extract absolute values of the London penetration
depth from our data and show that a crossover from local to nonlocal
electrodynamics occurs with increasing T when London penetration depth becomes
larger than the electrode thickness.


title:
Principes locaux-globaux pour certaines fibrations en torseurs sous un
  tore

abstract:
  Let $k$ be a number field and let $T$ be a $k$-torus. Consider a fibration in
torsors under $T$, i.e. a morphism $f: X \to \mathbb{P}^1_k$ from a smooth,
projective $k$-variety $X$ to $\mathbb{P}^1_k$ such that the generic fibre
$X_\eta \to \eta$ is a smooth compactification of a principal homogeneous space
under $T \times_k \eta$.
  We study the Brauer-Manin obstruction to the Hasse principle and weak
approximation for $X$, under Schinzel's hypothesis, thereby generalizing recent
work of Wei. Our results are unconditional if $k = \mathbb{Q}$ and the
non-split fibres of $f$ are defined over $\mathbb{Q}$.


title: Hierarchies of Predominantly Connected Communities

abstract:
  We consider communities whose vertices are predominantly connected, i.e., the
vertices in each community are stronger connected to other community members of
the same community than to vertices outside the community. Flake et al.
introduced a hierarchical clustering algorithm that finds such predominantly
connected communities of different coarseness depending on an input parameter.
We present a simple and efficient method for constructing a clustering
hierarchy according to Flake et al. that supersedes the necessity of choosing
feasible parameter values and guarantees the completeness of the resulting
hierarchy, i.e., the hierarchy contains all clusterings that can be constructed
by the original algorithm for any parameter value. However, predominantly
connected communities are not organized in a single hierarchy. Thus, we develop
a framework that, after precomputing at most $2(n-1)$ maximum flows, admits a
linear time construction of a clustering $\C(S)$ of predominantly connected
communities that contains a given community $S$ and is maximum in the sense
that any further clustering of predominantly connected communities that also
contains $S$ is hierarchically nested in $\C(S)$. We further generalize this
construction yielding a clustering with similar properties for $k$ given
communities in $O(kn)$ time. This admits the analysis of a network's structure
with respect to various communities in different hierarchies.


title: Principles of Adaptive Sorting Revealed by In Silico Evolution

abstract:
  Many biological networks have to filter out useful information from a vast
excess of spurious interactions. We use computational evolution to predict
design features of networks processing ligand categorization. The important
problem of early immune response is considered as a case-study. Rounds of
evolution with different constraints uncover elaborations of the same network
motif we name adaptive sorting. Corresponding network substructures can be
identified in current models of immune recognition. Our work draws a deep
analogy between immune recognition and biochemical adaptation.


title:
GPfit: An R package for Gaussian Process Model Fitting using a New
  Optimization Algorithm

abstract:
  Gaussian process (GP) models are commonly used statistical metamodels for
emulating expensive computer simulators. Fitting a GP model can be numerically
unstable if any pair of design points in the input space are close together.
Ranjan, Haynes, and Karsten (2011) proposed a computationally stable approach
for fitting GP models to deterministic computer simulators. They used a genetic
algorithm based approach that is robust but computationally intensive for
maximizing the likelihood. This paper implements a slightly modified version of
the model proposed by Ranjan et al. (2011), as the new R package GPfit. A novel
parameterization of the spatial correlation function and a new multi-start
gradient based optimization algorithm yield optimization that is robust and
typically faster than the genetic algorithm based approach. We present two
examples with R codes to illustrate the usage of the main functions in GPfit.
Several test functions are used for performance comparison with a popular R
package mlegp. GPfit is a free software and distributed under the general
public license, as part of the R software project (R Development Core Team
2012).


title: Probing QCD Phase Structure by Baryon Multiplicity Distribution

abstract:
  The canonical partition functions $Z_n$ and the number distributions $P_n$
which are obervable in experiments, are related by a single parameter, the
fugacities $\xi=\exp(\mu/T)$. With the charge parity invariance, $Z_n$ and
$\xi$ can be determined. Thermodynamic quantities such as the number density
susceptibility and the kurtosis are then calculated from the grand canonical
partition function $Z(\xi,T)=\sum Z_n(T) \xi^n$, ($n=-N_{\rm max},\cdots,
N_{\rm max}$), for any chemical potential $\mu$, although the region over which
the results are reliable for these quantities is constrained by $N_{\rm max}$.
  We then calculate the Lee-Yang zeros, which are the zeros of $Z(\xi)$ in the
complex fugacity plane, as poles of $d\log Z(\xi)/d\xi$ by using the Cauchy
integral theorem. With the help of a multiple precision library, this method
provides any precision required without misidentification of the zeros.
  We analyse $Z_n$ from the net-proton number distributions recently measured
at the Relativistic Heavy Ion Collider (RHIC) by assuming the net-proton number
is approximately propotional to that of the baryon after the freeze-out, and
calculate the moments. We also evaluate the Lee-Yang zero structures obtained
from RHIC data and compare them with those obtained from lattice quantum
chromodynamics (QCD) calculations.
  Possible regions of QCD phase transition lines are estimated from the
thermodynamics quantities and the Lee-Yang zeros. We discuss how the limited
$N_{\rm max}$ in both experimental and numerical studies affects the
reliability of the thermodynamic results and Lee-Yang zeros.


title: Constraining Recent Oscillations in Quintessence Models with Euclid

abstract:
  Euclid is a future space-based mission that will constrain dark energy with
unprecedented accuracy. Its photometric component is optimized for Weak Lensing
studies, while the spectroscopic component is designed for Baryon Acoustic
Oscillations (BAO) analysis. We use the Fisher matrix formalism to make
forecasts on two quintessence dark energy models with a dynamical equation of
state that leads to late-time oscillations in the expansion rate of the
Universe. We find that Weak Lensing will place much stronger constraints than
the BAO, being able to discriminate between oscillating models by measuring the
relevant parameters to $1\sigma$ precisions of 5 to $20\%$. The tight
constraints suggest that Euclid data could identify even quite small late-time
oscillations in the expansion rate of the Universe.


title: On minimal decomposition of $p$-adic homographic dynamical systems

abstract:
  A homographic map in the field of $p$-adic numbers $\mathbb{Q}_p}$ is studied
as a dynamical system on $\mathbb{P}^{1}(\mathbb{Q}_p)$, the projective line
over $\mathbb{Q}_p$. If such a system admits one or two fixed points in
$\mathbb{Q}_p$, then it is conjugate to an affine dynamics whose dynamical
structure has been investigated by Fan and Fares. In this paper, we shall
mainly solve the remaining case that the system admits no fixed point. We shall
prove that this system can be decomposed into a finite number of minimal
subsystems which are topologically conjugate to each other. All the minimal
subsystems are exhibited and the unique invariant measure for each minimal
subsystem is determined.


title: Quantifying the Impact of Parameter Tuning on Nature-Inspired Algorithms

abstract:
  The problem of parameterization is often central to the effective deployment
of nature-inspired algorithms. However, finding the optimal set of parameter
values for a combination of problem instance and solution method is highly
challenging, and few concrete guidelines exist on how and when such tuning may
be performed. Previous work tends to either focus on a specific algorithm or
use benchmark problems, and both of these restrictions limit the applicability
of any findings. Here, we examine a number of different algorithms, and study
them in a "problem agnostic" fashion (i.e., one that is not tied to specific
instances) by considering their performance on fitness landscapes with varying
characteristics. Using this approach, we make a number of observations on which
algorithms may (or may not) benefit from tuning, and in which specific
circumstances.


title:
Calculation of Exact Estimators by Integration Over the Surface of an
  n-Dimensional Sphere

abstract:
  This paper reconsiders the problem of calculating the expected set of
probabilities <p_i>, given the observed set of items {m_i}, that are
distributed among n bins with an (unknown) set of probabilities {p_i} for being
placed in the ith bin. The problem is often formulated using Bayes theorem and
the multinomial distribution, along with a constant prior for the values of the
p_i, leading to a Dirichlet distribution for the {p_i}. The moments of the p_i
can then be calculated exactly. Here a new approach is suggested for the
calculation of the moments, that uses a change of variables that reduces the
problem to an integration over a portion of the surface of an n-dimensional
sphere. This greatly simplifies the calculation by allowing a straightforward
integration over (n-1) independent variables, with the constraints on the set
of p_i being automatically satisfied. For the Dirichlet and similar
distributions the problem simplifies even further, with the resulting integrals
subsequently factorising, allowing their easy evaluation in terms of Beta
functions. A proof by induction confirms existing calculations for the moments.
The advantage of the approach presented here is that the methods and results
apply with minimum or no modifications to numerical calculations that involve
more complicated distributions or non-constant prior distributions, for which
cases the numerical calculations will be greatly simplified.


title: Energy levels of Th+ between 7.3 and 8.3 eV

abstract:
  Using resonant two-step laser excitation of trapped 232Th+ ions, we observe
43 previously unknown energy levels within the energy range from 7.3 to 8.3 eV.
The high density of states promises a strongly enhanced electronic bridge
excitation of the 229mTh nuclear state that is expected in this energy range.
From the observation of resonantly enhanced three-photon ionization of Th+, the
second ionization potential of thorium can be inferred to lie within the range
between 11.9 and 12.3 eV. Pulsed laser radiation in a wide wavelength range
from 237 to 289 nm is found to provide efficient photodissociation of molecular
ions that are formed in reactions of Th+ with impurities in the buffer gas,
leading to a significantly increased storage time for Th+ in the ion trap.


title:
Group theoretical and topological analysis of the quantum spin Hall
  effect in silicene

abstract:
  Silicene consists of a monolayer of silicon atoms in a buckled honeycomb
structure. It was recently discovered that the symmetry of such a system allows
for interesting Rashba spin-orbit effects. A perpendicular electric field is
able to couple to the sublattice pseudospin, making it possible to electrically
tune and close the band gap. Therefore, external electric fields may generate a
topological phase transition from a topological insulator to a normal insulator
(or semimetal) and vice versa. The contribution of the present article to the
study of silicene is twofold: First, we perform a group theoretical analysis to
systematically construct the Hamiltonian in the vicinity of the $K$ points of
the Brillouin zone and discover a new, but symmetry allowed term. Subsequently,
we identify a tight binding model that corresponds to the group theoretically
derived Hamiltonian near the $K$ points. Second, we start from this tight
binding model to analyze the topological phase diagram of silicene by an
explicit calculation of the $Z_2$ topological invariant of the band structure.
To this end, we calculate the $Z_2$ topological invariant of the honeycomb
lattice in a manifestly gauge invariant way which allows us to include $S_z$
symmetry breaking terms -- like Rashba spin orbit interaction -- into the
topological analysis. Interestingly, we find that the interplay of two Rashba
terms can generate a non-trivial quantum spin Hall phase in silicene. This is
in sharp contrast to the more extensively studied honeycomb system graphene
where Rashba spin orbit interaction is known to compete with the quantum spin
Hall effect in a potentially detrimental way.


title: Quasi-particle and matrix models of the semi Quark Gluon Plasma

abstract:
  We make a simple observation about two models used to treat the region near
the critical temperature of QCD, quasiparticle and matrix models. While they
appear very different, we show how these two models might be related. We also
present results for the temperature dependence of the ratio of the shear
viscosity to the entropy in a matrix model, and suggest that quasi-particle
models may behave similarly.


title: Kinetic exchange models: From molecular physics to social science

abstract:
  We discuss several multi-agent models that have their origin in the kinetic
exchange theory of statistical mechanics and have been recently applied to a
variety of problems in the social sciences. This class of models can be easily
adapted for simulations in areas other than physics, such as the modeling of
income and wealth distributions in economics and opinion dynamics in sociology.


title: Gamma-ray emission from nova outbursts

abstract:
  Classical novae produce radioactive nuclei which are emitters of gamma-rays
in the MeV range. Some examples are the lines at 478 and 1275 keV (from 7Be and
22Na) and the positron-electron annihilation emission, with the 511 keV line
and a continuum. Gamma-ray spectra and light curves are potential unique tools
to trace the corresponding isotopes and to give insights on the properties of
the expanding envelope. Another possible origin of gamma-rays is the
acceleration of particles up to very high energies, so that either neutral
pions or inverse Compton processes produce gamma-rays of energies larger than
100 MeV. MeV photons during nova explosions have not been detected yet,
although several attempts have been made in the last decades; on the other
hand, GeV photons from novae have been detected with the Fermi satellite in
V407 Cyg, a nova in a symbiotic binary, where the companion is a red giant with
a wind, instead of a main sequence star as in the cataclysmic variables hosting
classical novae. Two more novae have been detected recently (summer 2012) by
Fermi, apparently in non symbiotic binaries, thus challenging our understanding
of the emission mechanism. Both scenarios (radioactivities and acceleration) of
gamma-ray production in novae are discussed.


title:
Protostellar Disk Evolution Over Million-Year Timescales with a
  Prescription for Magnetized Turbulence

abstract:
  Magnetorotational instability (MRI) is the most promising mechanism behind
accretion in low-mass protostellar disks. Here we present the first analysis of
the global structure and evolution of non-ideal MRI-driven T-Tauri disks on
million-year timescales. We accomplish this in a 1+1D simulation by calculating
magnetic diffusivities and utilizing turbulence activity criteria to determine
thermal structure and accretion rate without resorting to a 3-D
magnetohydrodynamical (MHD) simulation. Our major findings are as follows.
First, even for modest surface densities of just a few times the minimum-mass
solar nebula, the dead zone encompasses the giant planet-forming region,
preserving any compositional gradients. Second, the surface density of the
active layer is nearly constant in time at roughly 10 g/cm2, which we use to
derive a simple prescription for viscous heating in MRI-active disks for those
who wish to avoid detailed MHD computations. Furthermore, unlike a standard
disk with constant-alpha viscosity, the disk midplane does not cool off over
time, though the surface cools as the star evolves along the Hayashi track. The
ice line is firmly in the terrestrial planet-forming region throughout disk
evolution and can move either inward or outward with time, depending on whether
pileups form near the star. Finally, steady-state mass transport is a poor
description of flow through an MRI-active disk. We caution that MRI activity is
sensitive to many parameters, including stellar X-ray flux, grain size,
gas/small grain mass ratio and magnetic field strength, and we have not
performed an exhaustive parameter study here.


title:
CO J=1-0 and J=2-1 Line Observations of the Molecular Cloud - Blocked
  Supernova Remnant 3C434.1

abstract:
  We present the results of CO emission line observations toward the
semicircular Galactic supernova remnant (SNR) 3C434.1 (G94.0+1.0). We mapped an
area covering the whole SNR in the 12CO J=1-0 emission line using the Seoul
Radio Astronomy Observatory (SRAO) 6-m telescope, and found a large molecular
cloud superposed on the faint western part of the SNR. The cloud was elongated
along the north-south direction and showed a very good spatial correlation with
the radio features of the SNR. We carried out 12CO J=2-1 line observations of
this cloud using the K\"{o}lner Observatorium f\"{u}r Sub-Millimeter Astronomie
(KOSMA) 3-m telescope and found a region in which the 12CO J=2-1 to J=1-0 ratio
was high (~ 1.6). This higher excitation, together with the morphological
relation, strongly suggested that the molecular cloud was interacting with the
SNR. The systemic velocity of the molecular cloud (-13 km/s) gave a kinematic
distance of 3.0 kpc to the SNR-molecular cloud system. We derived the physical
parameters of the SNR based on this new distance. We examined the variation of
the radio spectral index over the remnant and found that it was flatter in the
western part, wherein the SNR was interacting with the molecular cloud. We
therefore propose that 3C434.1 is the remnant of a supernova explosion that
occurred just outside the boundary of a relatively thin, sheetlike molecular
cloud. We present a hydrodynamic model showing that its asymmetric radio
morphology can result from its interaction with this blocking molecular cloud.


title: Mesoscopic theory for fluctuating active nematics

abstract:
  The term active nematics designates systems in which apolar elongated
particles spend energy to move randomly along their axis and interact by
inelastic collisions in the presence of noise. Starting from a simple
Vicsek-style model for active nematics, we derive a mesoscopic theory, complete
with effective multiplicative noise terms, using a combination of kinetic
theory and It\^o calculus approaches. The stochastic partial differential
equations thus obtained are shown to recover the key terms argued in EPL
\textbf{62} (2003) 196 to be at the origin of anomalous number fluctuations and
long-range correlations. Their deterministic part is studied analytically, and
is shown to give rise to the long-wavelength instability at onset of nematic
order (see arXiv:1011.5408). The corresponding nonlinear density-segregated
band solution is given in a closed form.


title: Non-uniqueness for the Euler equations: the effect of the boundary

abstract:
  We consider rotational initial data for the two-dimensional incompressible
Euler equations on an annulus. Using the convex integration framework, we show
that there exist infinitely many admissible weak solutions (i.e. such with
non-increasing energy) for such initial data. As a consequence, on bounded
domains there exist admissible weak solutions which are not dissipative in the
sense of P.-L. Lions, as opposed to the case without physical boundaries.
Moreover we show that admissible solutions are dissipative provided they are
H\"{o}lder continuous near the boundary of the domain.


title: Comments About the Electromagnetic Field in Heavy-Ion Collisions

abstract:
  In this short article we discuss the properties of electromagnetic fields in
heavy-ion collisions and consequences for observables. We address
quantitatively the issue of the magnetic field lifetime in a collision
including the electric and chiral magnetic conductivities. We show that for
reasonable parameters, the magnetic field created by spectators in a collision
is not modified by the presence of matter. Based on this, we draw definite
conclusions on observed effects in heavy-ion collisions.


title: Residual ideals of MacLane valuations

abstract:
  Let $K$ be a field equipped with a discrete valuation $v$. In a pioneering
work, S. MacLane determined all valuations on $K(x)$ extending $v$. His work
was recently reviewed and generalized by M. Vaqui\'e, by using the graded
algebra of a valuation. We extend Vaqui\'e's approach by studying residual
ideals of the graded algebra of a valuation as an abstract counterpart of
certain residual polynomials which play a key role in the computational
applications of the theory. As a consequence, we determine the structure of the
graded algebra of the discrete valuations on $K(x)$ and we show how these
valuations may be used to parameterize irreducible polynomials over local
fields up to Okutsu equivalence.


title: Mixing of the Glauber dynamics for the ferromagnetic Potts model

abstract:
  We present several results on the mixing time of the Glauber dynamics for
sampling from the Gibbs distribution in the ferromagnetic Potts model. At a
fixed temperature and interaction strength, we study the interplay between the
maximum degree ($\Delta$) of the underlying graph and the number of colours or
spins ($q$) in determining whether the dynamics mixes rapidly or not. We find a
lower bound $L$ on the number of colours such that Glauber dynamics is rapidly
mixing if at least $L$ colours are used. We give a closely-matching upper bound
$U$ on the number of colours such that with probability that tends to 1, the
Glauber dynamics mixes slowly on random $\Delta$-regular graphs when at most
$U$ colours are used. We show that our bounds can be improved if we restrict
attention to certain types of graphs of maximum degree $\Delta$, e.g. toroidal
grids for $\Delta = 4$.


title: Gravitational waves: a foundational review

abstract:
  The standard linear approach to the gravitational waves theory is critically
reviewed. Contrary to the prevalent understanding, it is pointed out that this
theory contains many conceptual and technical obscure issues that require
further analysis.


title: Localization and a generalization of MacDonald's inner product

abstract:
  We find a limit formula for a generalization of MacDonald's inner product in
finitely many variables, using equivariant localization on the Grassmannian
variety, and the main lemma from \cite{Car}, which bounds the torus characters
of the higher \c{C}ech cohomology groups. We show that the MacDonald inner
product conjecture of type $A$ follows from a special case, and the Pieri rules
section of MacDonald's book \cite{Mac}, making this limit suitable replacement
for the norm squared of one, the usual normalizing constant.


title: Equations for lower bounds on border rank

abstract:
  We present new methods for determining polynomials in the ideal of the
variety of bilinear maps of border rank at most r. We apply these methods to
several cases including the case r = 6 in the space of bilinear maps C^4 x C^4
-> C^4. This space of bilinear maps includes the matrix multiplication operator
M_2 for two by two matrices. We show these newly obtained polynomials do not
vanish on the matrix multiplication operator M_2, which gives a new proof that
the border rank of the multiplication of 2 x 2 matrices is seven. Other
examples are considered along with an explanation of how to implement the
methods.


title: Contingency-Risk Informed Power System Design

abstract:
  We consider the problem of designing (or augmenting) an electric power system
at a minimum cost such that it satisfies the N-k-e survivability criterion.
This survivability criterion is a generalization of the well-known N-k
criterion, and it requires that at least (1- e_j) fraction of the total demand
to be met after failures of up to j components, for j=1,...,k. The network
design problem adds another level of complexity to the notoriously hard
contingency analysis problem, since the contingency analysis is only one of the
requirements for the design optimization problem. We present a mixed-integer
programming formulation of this problem that takes into account both
transmission and generation expansion. We propose an algorithm that can avoid
combinatorial explosion in the number of contingencies, by seeking
vulnerabilities in intermediary solutions and constraining the design space
accordingly. Our approach is built on our ability to identify such system
vulnerabilities quickly. Our empirical studies on modified instances from the
IEEE 30-bus and IEEE 57-bus systems show the effectiveness of our methods. We
were able to solve the transmission and generation expansion problems for k=4
under 2 minutes, while other approaches failed to provide a solution at the end
of 2 hours.


title: Quantitative analysis of the debonding structure of soft adhesives

abstract:
  We experimentally investigate the growth dynamics of cavities nucleating
during the first stages of debonding of three different model adhesives. The
material properties of these adhesives range from a more liquid-like material
to a soft viscoelastic solid and are carefully characterized by small strain
oscillatory shear rheology as well as large strain uniaxial extension. The
debonding experiments are performed on a probe tack set-up. Using high contrast
images of the debonding process and precise image analysis tools we quantify
the total projected area of the cavities, the average cavity shape and growth
rate and link these observations to the material properties. These measurements
are then used to access corrected effective stress and strain curves that can
be directly compared to the results from the uniaxial extension.


title:
Cell body rocking is a dominant mechanism for flagellar synchronization
  in a swimming alga

abstract:
  The unicellular green algae Chlamydomonas swims with two flagella, which can
synchronize their beat. Synchronized beating is required to swim both fast and
straight. A long-standing hypothesis proposes that synchronization of flagella
results from hydrodynamic coupling, but the details are not understood. Here,
we present realistic hydrodynamic computations and high-speed tracking
experiments of swimming cells that show how a perturbation from the
synchronized state causes rotational motion of the cell body. This rotation
feeds back on the flagellar dynamics via hydrodynamic friction forces and
rapidly restores the synchronized state in our theory. We calculate that this
`cell body rocking' provides the dominant contribution to synchronization in
swimming cells, whereas direct hydrodynamic interactions between the flagella
contribute negligibly. We experimentally confirmed the coupling between
flagellar beating and cell body rocking predicted by our theory. This work
appeared also in the Proceedings of the National Academy of Science of the
U.S.A as: Geyer et al., PNAS 110(45), p. 18058(6), 2013.


title:
Synchrotron-to-curvature transition regime of radiation of charged
  particles in a dipole magnetic field

abstract:
  The details of trajectories of charged particles become increasingly
important for proper understanding of processes of formation of radiation in
strong and curved magnetic fields. Because of damping of the perpendicular
component of motion, the particle's pitch angle could be decreased by many
orders of magnitude leading to the change of the radiation regime -- from
synchrotron to the curvature mode. To explore the character of this transition,
we solve numerically the equations of motion of a test particle in a dipole
magnetic field, and calculate the energy spectrum of magnetic bremsstrahlung
self-consistently, i.e. without a priori assumptions on the radiation regime.
In this way we can trace the transitions between the synchrotron and curvature
regimes, as well as study the third (intermediate or the so-called
synchro-curvature) regime. We briefly discuss three interesting astrophysical
scenarios, the radiation of electrons in the pulsar magnetosphere in the polar
cap and outer gap models, as well as the radiation of ultrahigh energy protons
in the magnetosphere of a massive black hole, and demonstrate that in these
models the synchrotron, synchro-curvature and curvature regimes can be realized
with quite different relative contributions to the total emission.