title: Results on \phi 2 from e+e- colliders

abstract:
  We present a summary of measurements sensitive to the CKM angle \phi 2
(\alpha), performed by the BaBar and the Belle experiments which both collect
B\bar{B} pairs produced at the \Upsilon(4S) resonance in asymmetric e+e-
collisions. We discuss the decays B -> \pi \pi, \rho\rho, a_1\pi and
(\rho\pi)^0. The CP asymmetries, branching fractions and polarizations obtained
are used to constrain \phi 2.


title:
Evidence for exclusion of the possibility of $d$-wave
  superconducting-gap symmetry in Ba-doped KFe$_2$As$_2$

abstract:
  We have investigated the superconducting(SC)-gap anisotropy for several
Ba-doped KFe$_2$As$_2$ samples using laser-based angle-resolved photoemission
spectroscopy. We show that the SC-gap anisotropy and node positions drastically
change with a small amount of Ba doping. Our results totally exclude a
possibility of $d$-wave symmetry and strongly suggest that both spin and
orbital fluctuations are important for the paring interaction in the Ba-doped
K122.


title: Nuclear lattice simulations: Status and perspectives

abstract:
  I review the present status of nuclear lattice simulations.
  This talk is dedicated to the memory of Gerald E. Brown.


title:
Ensemble fermions for electroweak dynamics and the fermion preheating
  temperature

abstract:
  We refine the implementation of ensemble fermions for the electroweak sector
of the Standard Model, introduced previously. We consider the behavior of
different observables as the size of the ensemble is increased and show that
the dynamics converges for ensemble sizes small enough that simulations of the
entire electroweak sector become numerically tractable. We apply the method to
the computation of the effective preheating temperature during a fast
electroweak transition, relevant for Cold Electroweak Baryogenesis. We find
that this temperature is never below 20 GeV, and this in combination with the
early results convincingly rules out Standard Model CP-violation as the origin
of the baryon asymmetry of the Universe.


title: Detecting Superbubbles in Assembly Graphs

abstract:
  We introduce a new concept of a subgraph class called a superbubble for
analyzing assembly graphs, and propose an efficient algorithm for detecting it.
Most assembly algorithms utilize assembly graphs like the de Bruijn graph or
the overlap graph constructed from reads. From these graphs, many assembly
algorithms first detect simple local graph structures (motifs), such as tips
and bubbles, mainly to find sequencing errors. These motifs are easy to detect,
but they are sometimes too simple to deal with more complex errors. The
superbubble is an extension of the bubble, which is also important for
analyzing assembly graphs. Though superbubbles are much more complex than
ordinary bubbles, we show that they can be efficiently enumerated. We propose
an average-case linear time algorithm (i.e., O(n+m) for a graph with n vertices
and m edges) for graphs with a reasonable model, though the worst-case time
complexity of our algorithm is quadratic (i.e., O(n(n+m))). Moreover, the
algorithm is practically very fast: Our experiments show that our algorithm
runs in reasonable time with a single CPU core even against a very large graph
of a whole human genome.


title:
Symmetry Protected Quantization and Bulk-Edge Correspondence of Massless
  Dirac Fermions: Application to Fermionic Shastry-Sutherland Model

abstract:
  The fermionic Shastry-Sutherland model has a rich phase diagram, including
phases with massless Dirac fermions, a quadratic band crossing point, and a
pseudospin-1 Weyl fermion. Berry phases defined by the one-dimensional momentum
as a parameter are quantized into 0 or pi due to the inversion symmetry
combined with the time reversal, or existence of the glide plane, which also
protects the massless Dirac cones with continuous parameters. This is the
symmetry protected Z2 quantization. We have further demonstrated the Z2 Berry
phases generically determine the existence of edge states in various phases and
with different types of the boundaries as the bulk-edge correspondence of the
massless Dirac fermion systems.


title: Multi-User Non-Locality Amplification

abstract:
  Non-local correlations are among the most fascinating features of quantum
theory from the point of view of information: Such correlations, although not
allowing for signaling, are unexplainable by pre-shared information. The
correlations have applications in cryptography, communication complexity, and
sit at the very heart of many attempts of understanding quantum theory -- and
its limits -- in terms of classical information. In these contexts, the
question is crucial whether such correlations can be amplified or distilled,
i.e., whether and how weak correlations can be used for generating (a smaller
amount of) stronger. Whereas the question has been studied quite extensively
for bipartite correlations (yielding both pessimistic and optimistic results),
only little is known in the multi-partite case. We introduce a general
framework of reductions between multi-party input-output systems. Within this
formalism, we show that a natural n-party generalization of the well-known
Popescu-Rohrlich box can be distilled, by an adaptive protocol, to the
algebraic maximum.We use this result further to show that a much broader class
of correlations, including all purely threepartite correlations, can be
distilled from arbitrarily weak to almost maximal strength with partial
communication, i.e., using only a subset of the channels required for the
creation of the same correlation from scratch. Alternatively, this means that
arbitrarily weak non-local correlations can have a "communication value" in the
context of the generation of maximal non-locality.


title: Topological games and productively countably tight spaces

abstract:
  The two main results of this work are the following: if a space $X$ is such
that player II has a winning strategy in the game $\gone(\Omega_x, \Omega_x)$
for every $x \in X$, then $X$ is productively countably tight. On the other
hand, if a space is productively countably tight, then $\sone(\Omega_x,
\Omega_x)$ holds for every $x \in X$. With these results, several other results
follow, using some characterizations made by Uspenskii and Scheepers.


title: Coherence and Negative Sectional Curvature in Complexes of Groups

abstract:
  We examine a condition on a simply connected 2-complex X ensuring that groups
acting properly on X are coherent. This extends earlier work on 2-complexes
with negative sectional curvature which covers the case that G acts freely. Our
extension of these results involves a generalization of the notion of sectional
curvature, an extension of the combinatorial Gauss-Bonnet theorem to complexes
of groups, and surprisingly requires the use of L^2-Betti numbers. We also
prove local quasiconvexity of G under the additional assumption that X is
CAT(0) space.


title:
On the sharp effect of attaching a thin handle on the spectral rate of
  convergence

abstract:
  Consider two domains connected by a thin tube: it can be shown that the
resolvent of the Dirichlet Laplacian is continuous with respect to the channel
section parameter. This in particular implies the continuity of isolated simple
eigenvalues and the corresponding eigenfunctions with respect to domain
perturbation. Under an explicit nondegeneracy condition, we improve this
information providing a sharp control of the rate of convergence of the
eigenvalues and eigenfunctions in the perturbed domain to the relative
eigenvalue and eigenfunction in the limit domain. As an application, we prove
that, again under an explicit nondegeneracy con- dition, the case of resonant
domains features polinomial splitting of the two eigenvalues and a clear
bifurcation of eigenfunctions.


title: An Overview of the Pathway Idea in Statistical and Physical Sciences

abstract:
  Pathway idea is a switching mechanism by which one can go from one functional
form to another, and to yet another. It is shown that through a parameter
$\alpha$, called the pathway parameter, one can connect generalized type-1 beta
family of densities, generalized type-2 beta family of densities, and
generalized gamma family of densities, in the scalar as well as the matrix
cases, also in the real and complex domains. It is shown that when the model is
applied to physical situations then the current hot topics of Tsallis
statistics and superstatistics in statistical mechanics become special cases of
the pathway model, and the model is capable of capturing many stable situations
as well as the unstable or chaotic neighborhoods of the stable situations and
transitional stages. The pathway model is shown to be connected to generalized
information measures or entropies, power law, likelihood ratio criterion or
$\lambda-$criterion in multivariate statistical analysis, generalized Dirichlet
densities, fractional calculus, Mittag-Leffler stochastic process, Kr\"{a}tzel
integral in applied analysis, and many other topics in different disciplines.
The pathway model enables one to extend the current results on quadratic and
bilinear forms, when the samples come from Gaussian populations, to wider
classes of populations.

categories: math-ph math.CV math.MP math.ST physics.space-ph stat.TH


title: A More General Maximal Bernstein-type Inequality

abstract:
  We extend a general Bernstein-type maximal inequality of Kevei and Mason
(2011) for sums of random variables.


title: Cerulean: A hybrid assembly using high throughput short and long reads

abstract:
  Genome assembly using high throughput data with short reads, arguably,
remains an unresolvable task in repetitive genomes, since when the length of a
repeat exceeds the read length, it becomes difficult to unambiguously connect
the flanking regions. The emergence of third generation sequencing (Pacific
Biosciences) with long reads enables the opportunity to resolve complicated
repeats that could not be resolved by the short read data. However, these long
reads have high error rate and it is an uphill task to assemble the genome
without using additional high quality short reads. Recently, Koren et al. 2012
proposed an approach to use high quality short reads data to correct these long
reads and, thus, make the assembly from long reads possible. However, due to
the large size of both dataset (short and long reads), error-correction of
these long reads requires excessively high computational resources, even on
small bacterial genomes. In this work, instead of error correction of long
reads, we first assemble the short reads and later map these long reads on the
assembly graph to resolve repeats.
  Contribution: We present a hybrid assembly approach that is both
computationally effective and produces high quality assemblies. Our algorithm
first operates with a simplified version of the assembly graph consisting only
of long contigs and gradually improves the assembly by adding smaller contigs
in each iteration. In contrast to the state-of-the-art long reads error
correction technique, which requires high computational resources and long
running time on a supercomputer even for bacterial genome datasets, our
software can produce comparable assembly using only a standard desktop in a
short running time.


title: On The Notions of Mating

abstract:
  The different notions of matings of pairs of equal degree polynomials are
introduced and are related to each other as well as known results on matings.
The possible obstructions to matings are identified and related. Moreover the
relations between the polynomials and their matings are discussed and proved.
Finally holomorphic motion properties of slow-mating are proved.


title:
Axion-induced birefringence effects in laser driven nonlinear vacuum
  interaction

abstract:
  The propagation of a probe electromagnetic field through a counterpropagating
strong plane wave is investigated. The effects of the electromagnetic
field-(pseudo)scalar axion field interaction and of the self-interaction of the
electromagnetic field mediated by virtual electron-positron pairs in the
effective Lagrangian approach are included. First, we show that if the strong
field is circularly polarized, contrary to the leading-order nonlinear QED
effects, the axion-photon interaction induces a chiral-like birefringence and a
dichroism in the vacuum. The latter effect is explained by evoking the
conservation of the total angular momentum along the common propagation
direction of probe and the strong wave, which allows for real axion production
only for probe and strong fields with the same helicity. Moreover, in the case
of ultra-short strong pulses, it is shown that the absorption coefficients of
probe photons depend on the form of the pulse and, in particular, on the
carrier-envelope phase of the strong beam. The present results can be exploited
experimentally to isolate nonlinear vacuum effects stemming from light-axion
interaction, especially at upcoming ultra-strong laser facilities, where
stringent constraints on the axion-photon coupling constant are in principle
provided.


title:
Neutrino signature of supernova hydrodynamical instabilities in three
  dimensions

abstract:
  The first full-scale three-dimensional (3D) core-collapse supernova (SN)
simulations with sophisticated neutrino transport show pronounced effects of
the standing accretion shock instability (SASI) for two high-mass progenitors
(20 and 27 M_sun). In a low-mass progenitor (11.2 M_sun), large-scale
convection is the dominant nonradial hydrodynamic instability in the postshock
accretion layer. The SASI-associated modulation of the neutrino signal (80 Hz
in our two examples) will be clearly detectable in IceCube or the future
Hyper-Kamiokande detector, depending on progenitor properties, distance, and
observer location relative to the main SASI sloshing direction. The neutrino
signal from the next galactic SN can therefore diagnose the nature of the
hydrodynamic instability.


title: A smooth polaron-molecule crossover in a Fermi system

abstract:
  The problem of a single down spin particle interacting with a Fermi sea of up
spin particles is of current interest in the field of cold atoms. The Hubbard
model, appropriate to atoms in an optical lattice potential, is considered in
parallel with a gas model. As the strength of an attractive short-range
interaction is increased there is a crossover from "polaron" behaviour, in
which the Fermi sea is weakly perturbed, to "molecule" behaviour in which the
down spin particle is bound to a single up spin particle. It is shown that this
is a smooth crossover, not a sharp transition as claimed by many authors.


title: Non-minimal Inflationary Attractors

abstract:
  Recently we identified a new class of (super)conformally invariant theories
which allow inflation even if the scalar potential is very steep in terms of
the original conformal variables. Observational predictions of a broad class of
such theories are nearly model-independent. In this paper we consider
generalized versions of these models where the inflaton has a non-minimal
coupling to gravity with \xi <0 different from its conformal value \xi = -1/6.
We show that these models exhibit attractor behavior. With even a slight
increase of |\xi| from |\xi| = 0, predictions of these models for n_s and r
rapidly converge to their universal model-independent values corresponding to
conformal coupling \xi = -1/6. These values of n_s and r practically coincide
with the corresponding values in the limit of infinitely large negative \xi.


title:
Post-selection free, integrated optical source of non-degenerate,
  polarization entangled photon pairs

abstract:
  We present an integrated source of polarization entangled photon pairs in the
telecom regime, which is based on type II-phasematched parametric
down-conversion (PDC) in a Ti-indiffused waveguide in periodically poled
lithium niobate. The domain grating -- consisting of an interlaced bi-periodic
structure -- is engineered to provide simultaneous phase-matching of two PDC
processes, and enables the direct generation of non-degenerate, polarization
entangled photon pairs with a brightness of $B=7\times10^3$ pairs/(s mW GHz).
The spatial separation of the photon pairs is accomplished by a fiber-optical
multiplexer facilitating a high compactness of the overall source. Visibilities
exceeding 95% and a violation of the Bell inequality with $S=2.57\pm0.06$ could
be demonstrated.


title: Rigidity of extremal quasiregularly elliptic manifolds

abstract:
  We show that for a closed $n$-manifold $N$ admitting a quasiregular mapping
from the Euclidean $n$-space the following are equivalent: (1) order of growth
of $\pi_1(N)$ is $n$, (2) $N$ is aspherical, and (3) $\pi_1(N)$ is virtually
$\mathbb{Z}^n$ and torsion free.


title:
Sibelia: A scalable and comprehensive synteny block generation tool for
  closely related microbial genomes

abstract:
  Comparing strains within the same microbial species has proven effective in
the identification of genes and genomic regions responsible for virulence, as
well as in the diagnosis and treatment of infectious diseases. In this paper,
we present Sibelia, a tool for finding synteny blocks in multiple closely
related microbial genomes using iterative de Bruijn graphs. Unlike most other
tools, Sibelia can find synteny blocks that are repeated within genomes as well
as blocks shared by multiple genomes. It represents synteny blocks in a
hierarchy structure with multiple layers, each of which representing a
different granularity level. Sibelia has been designed to work efficiently with
a large number of microbial genomes; it finds synteny blocks in 31 S. aureus
genomes within 31 minutes and in 59 E.coli genomes within 107 minutes on a
standard desktop. Sibelia software is distributed under the GNU GPL v2 license
and is available at: https://github.com/bioinf/Sibelia Sibelia's web-server is
available at: http://etool.me/software/sibelia


title:
The Lorenz model for single-mode homogeneously broadened laser:
  analytical determination of the unpredictible zone

abstract:
  We have applied harmonic expansion to derive an analytical solution for the
Lorenz-Haken equations. This method is used to describe the regular and
periodic self-pulsing regime of the single mode homogeneously broadened laser.
These periodic solutions emerge when the ratio of the population decay rates is
smaller than 0.11. We have also demonstrated the tendency of the Lorenz-Haken
dissipative system to behave periodic for a characteristic pumping rate "2CP"
[4], close to the second laser threshold "2C2th" (threshold of instability).
When the pumping parameter "2C" increases, the laser undergoes a
period-doubling sequence. This cascade of period doubling leads towards chaos.
We study this type of solutions and indicate the zone of the control parameters
for which the system undergoes irregular pulsing solutions. We had previously
applied this analytical procedure to derive the amplitude of the first, third
and the fifth order harmonics for the laser-field expansion [4, 14]. In this
work, we extend this method in the aim of obtaining the higher harmonics. We
show that this iterative method is indeed limited to the fifth order, and that
above, the obtained analytical solution diverges from the numerical direct
resolution of the equations.


title:
The Implications of Diverse Applications and Scalable Data Sets in
  Benchmarking Big Data Systems

abstract:
  Now we live in an era of big data, and big data applications are becoming
more and more pervasive. How to benchmark data center computer systems running
big data applications (in short big data systems) is a hot topic. In this
paper, we focus on measuring the performance impacts of diverse applications
and scalable volumes of data sets on big data systems. For four typical data
analysis applications---an important class of big data applications, we find
two major results through experiments: first, the data scale has a significant
impact on the performance of big data systems, so we must provide scalable
volumes of data sets in big data benchmarks. Second, for the four applications,
even all of them use the simple algorithms, the performance trends are
different with increasing data scales, and hence we must consider not only
variety of data sets but also variety of applications in benchmarking big data
systems.


title:
Surface transport properties of Fe-based superconductors: The influence
  of degradation and inhomogeneity

abstract:
  Surface properties of Co-doped BaFe2As2 epitaxial superconducting thin films
were inspected by X-ray photoelectron spectroscopy, scanning spreading
resistance microscopy (SSRM), and point contact spectroscopy (PCS). It has been
shown that surface of Fe-based superconductors degrades rapidly if being
exposed to air, what results in suppression of gap-like structure on PCS
spectra. Moreover, SSRM measurements revealed inhomogeneous surface
conductivity, what is consistent with strong dependence of PCS spectra on
contact position. Presented results suggest that fresh surface and small
probing area should be assured for surface sensitive measurements like PCS to
obtain intrinsic properties of Fe-based superconductors.


title: Naive boundary strata and nilpotent orbits

abstract:
  We study certain real Lie-group orbits in the compact duals of Mumford-Tate
domains, verifying a prediction made in [Green, Griffiths, Kerr; Mumford-Tate
domains: their geometry and arithmetic] and determining which orbits contain a
limit point of some period map. A variety of examples are worked out for the
groups SU(2,1), Sp_4, and G_2.


title: Noncommutative motives of Azumaya algebras

abstract:
  Let k be a base commutative ring, R a commutative ring of coefficients, X a
quasi-compact quasi-separated k-scheme, A a sheaf of Azumaya algebras over X of
rank r, and Hmo(R) the category of noncommutative motives with R-coefficients.
Assume that 1/r belongs to R. Under this assumption, we prove that the
noncommutative motives with R-coefficients of X and A are isomorphic. As an
application, we show that all the R-linear additive invariants of X and A are
exactly the same. Examples include (nonconnective) algebraic K-theory, cyclic
homology (and all its variants), topological Hochschild homology, etc. Making
use of these isomorphisms, we then computer the R-linear additive invariants of
differential operators in positive characteristic, of cubic fourfolds
containing a plane, of Severi-Brauer varieties, of Clifford algebras, of
quadrics, and of finite dimensional k-algebras of finite global dimension.
Along the way we establish two results of independent interest. The first one
asserts that every element of the Grothendieck group of X which has rank r
becomes invertible in the R-linearized Grothendieck group, and the second one
that every additive invariant of finite dimensional algebras of finite global
dimension is unaffected under nilpotent extensions.


title: Error analysis and lattice improvement for the C-ADS Injector-I

abstract:
  The injector (Scheme-I) of the C-ADS linac is a 10-mA 10-MeV proton linac
working in CW mode. It is mainly comprised of a 3.2-MeV room-temperature 4-vane
RFQ and twelve superconducting single-spoke cavities housed in a long cryostat.
Error analysis including alignment and field errors, static and dynamic ones
for the injector are presented. Based on detailed numerical simulations, an
orbit correction scheme has been designed. It shows that with correction the
rms residual orbit errors can be controlled within 0.3 mm and a beam loss rate
of 1.7*10^-6 is obtained. To reduce the beam loss rate further, an improved
lattice design for the superconducting spoke cavity section has been studied.


title: On the accuracy of the Viterbi alignment

abstract:
  In a hidden Markov model, the underlying Markov chain is usually hidden.
Often, the maximum likelihood alignment (Viterbi alignment) is used as its
estimate. Although having the biggest likelihood, the Viterbi alignment can
behave very untypically by passing states that are at most unexpected. To avoid
such situations, the Viterbi alignment can be modified by forcing it not to
pass these states. In this article, an iterative procedure for improving the
Viterbi alignment is proposed and studied. The iterative approach is compared
with a simple bunch approach where a number of states with low probability are
all replaced at the same time. It can be seen that the iterative way of
adjusting the Viterbi alignment is more efficient and it has several advantages
over the bunch approach. The same iterative algorithm for improving the Viterbi
alignment can be used in the case of peeping, that is when it is possible to
reveal hidden states. In addition, lower bounds for classification
probabilities of the Viterbi alignment under different conditions on the model
parameters are studied.


title:
Limiting Approach to Generalized Gamma Bessel Model via Fractional
  Calculus and its Applications in Various Disciplines

abstract:
  The essentials of fractional calculus according to different approaches that
can be useful for our applications in the theory of probability and stochastic
processes are established. In addition to this, from this fractional integral
one can list out almost all the extended densities for the pathway parameter $q
< 1$ and $q \rightarrow 1$. Here we bring out the idea of thicker or thinner
tailed models associated with a gamma type distribution as a limiting case of
pathway operator. Applications of this extended gamma model in Statistical
Mechanics, input-output models, and solar spectral irradiance modeling etc are
established.

categories: math-ph math.MP math.ST physics.data-an stat.TH


title:
Revealing the missing heritability via cross-validated genome-wide
  association studies

abstract:
  Presented here is a simple method for cross-validated genome-wide association
studies (cvGWAS). Focusing on phenotype prediction, the method is able to
reveal a significant amount of missing heritability by properly selecting a
small number of loci with implicit predictive ability. The results provide new
insights into the missing heritability problem and the underlying genetic
architecture of complex traits.


title: Complexity Analysis in Cyclic Tag System Emulated by Rule 110

abstract:
  It is known that elementary cellular automaton rule 110 is capable of
supporting universal computation by emulating cyclic tag system. Since the
whole information necessary to perform computation is stored in the
configuration, it is reasonable to investigate the complexity of configuration
for the analysis of computing process. In this research we employed Lempel-Ziv
complexity as a measure of complexity and calculated it during the evolution of
emulating cyclic tag system by rule 110. As a result, we observed the stepwise
decline of complexity during the evolution. That is caused by the
transformation from table data to moving data and the elimination of table data
by a rejector.


title: On Vervaat transform of Brownian bridges and Brownian motion

abstract:
  For a continuous function $f \in \mathcal{C}([0,1])$, define the Vervaat
transform $V(f)(t):=f(\tau(f)+t \mod1)+f(1)1_{\{t+\tau(f) \geq
1\}}-f(\tau(f))$, where $\tau(f)$ corresponds to the first time at which the
minimum of $f$ is attained. Motivated by recent study of quantile transforms
for random walks and Brownian motion, we study the Vervaat transform of
Brownian motion and Brownian bridges with arbitary endpoints. When the two
endpoints of the bridge are not the same, the Vervaat transform is not
Markovian. We describe its distribution by path decompositions and study its
semimartingale properties. The expectation and variance of the Vervaat
transform of Brownian motion are also derived.


title:
Unconventional superconductivity in a two-dimensional repulsive gas of
  fermions with spin-orbit coupling

abstract:
  We investigate the superconducting instability of a two-dimensional repulsive
fermion gas with Rashba spin-orbit coupling $\al_R$. Using renormalization
group approach, we find the superconducting transition temperature as a
function of the dimensionless ratio $\Theta={1}{2}m\al_R^2/E_F$ where $E_F=0$
when the smaller Fermi surface shrinks to a (Dirac) point. The general trend is
that superconductivity is enhanced as $\Theta$ increases, but in an
intermediate regime $\Theta\sim0.1$, a dome-like behavior appears. At a very
small value of $\Theta$, the angular momentum channel $j_z$ in which
superconductivity occurs is quite high. With increasing $\Theta$, $j_z$
decreases with a step of 2 down to $j_z=6$, after which we find the sequence
$j_z=6, 4, 6, 2$, the last value of which continues to
$\Theta\rightarrow\infty$. In an extended range of $\Theta$, the
superconducting gap predominantly resides on the large Fermi surface, while
Josephson coupling induces a much smaller gap on the small Fermi surface. Below
the superconducting transition temperature, we apply mean field theory to
derive the self-consistent equations and find the condensation energies. The
state with the lowest condensation energy is an unconventional superconducting
state which breaks time reversal symmetry, and in which singlet and triplet
pairings are mixed. In general, these states are topologically nontrivial, and
the Chern number of the state with total angular momentum $j_z$ is $C=2j_z$.


title: Zoology of instanton solutions in flat potential barriers

abstract:
  We perform a detailed study of the existence and the properties of
O(4)-invariant instanton solutions in Einstein-scalar theory in the presence of
flat potential barriers, i.e. barriers where the second derivative of the
potential is small at the top of the barrier. We find a whole zoo of solutions:
Hawking-Moss, Coleman-De Luccia (CdL), oscillating instantons, asymmetric CdL
as well as other non-standard CdL-like solutions with additional negative modes
in their spectrum of fluctuations. Our work shows how these different branches
of solutions are connected to each other via "critical" instantons possessing
an extra zero mode fluctuation. Overall, the space of finite action euclidean
solutions to these theories with flat barriers is surprisingly rich and
intricate.


title: On capacitary strong type inequalities for Orlicz-Sobolev functions

abstract:
  We prove capacitary strong type inequalities for functions belonging to
Orlicz-Sobolev spaces. As an application we consider capacitary averages and
their limits.


title: Weil transfer of noncommutative motives

abstract:
  The Weil restriction functor, introduced in the late fifties, was recently
extended by Karpenko to the category of Chow motives with integral
coefficients. In this article we introduce the noncommutative (=NC) analogue of
the Weil restriction functor, where schemes are replaced by dg algebras, and
extend it to Kontsevich's categories of NC Chow motives and NC numerical
motives. Instead of integer coefficients, we work more generally with
coefficients in a binomial ring. Along the way, we extend Karpenko's functor to
the classical category of numerical motives, and compare this extension with
its NC analogue. As an application, we compute the (NC) Chow motive of the Weil
restriction of every smooth projective scheme whose category of perfect
complexes admits a full exceptional collection. Finally, in the case of central
simple algebras, we describe explicitly the NC analogue of the Weil restriction
functor using solely the degree of the field extension. This leads to a
"categorification" of the classical corestriction homomorphism between Brauer
groups.


title: Quadratic First Integrals of Kinetic Differential Equations

abstract:
  Classes of kinetic differential equations are delineated which do have a
quadratic first integral, and classes which can not have one. Example reactions
corresponding to the obtained kinetic differential equations are shown, and a
few figures showing the trajectories of the corresponding systems are also
included. Connections to other areas are mentioned and unsolved problems
collected. The new results are theoretical, although computational tools are
heavily used. Applications from biology and combustion theory will come later.


title: Banach spaces with no proximinal subspaces of codimension 2

abstract:
  The classical theorem of Bishop-Phelps asserts that, for a Banach space X,
the norm-achieving functionals in X* are dense in X*. Bela Bollobas's extension
of the theorem gives a quantitative description of just how dense the
norm-achieving functionals have to be: if (x,f) is in X x X* with ||x||=||f||=1
and |1-f(x)|< h^2/4 then there are (x',f') in X x X* with ||x'||= ||f'||=1,
||x-x'||, ||f-f'||< h and f'(x')=1.
  This means that there are always "proximinal" hyperplanes H in X (a nonempty
subset E of a metric space is said to be "proximinal" if, for x not in E, the
distance d(x,E) is always achieved - there is always an e in E with
d(x,E)=d(x,e)); for if H= ker f (f in X*) then it is easy to see that H is
proximinal if and only if f is norm-achieving. Indeed the set of proximinal
hyperplanes H is, in the appropriate sense, dense in the set of all closed
hyperplanes H in X.
  Quite a long time ago [Problem 2.1 in his monograph "The Theory of Best
approximation and Functional Analysis" Regional Conference series in Applied
Mathematics, SIAM, 1974], Ivan Singer asked if this result generalized to
closed subspaces of finite codimension - if every Banach space has a proximinal
subspace of codimension 2, for example. In this paper I show that there is a
Banach space X such that X has no proximinal subspace of finite codimension
n>1. So we have a converse to Bishop-Phelps-Bollobas: a dense set of proximinal
hyperplanes can always be found, but proximinal subspaces of larger, finite
codimension need not be.


title: Electrodynamics of a ring-shaped spiral resonator

abstract:
  We present analytical, numerical and experimental investigations of
electromagnetic resonant modes of a compact monofilar Archimedean spiral
resonator shaped in a ring, with no central part. Planar spiral resonators are
interesting as components of metamaterials for their compact deep-subwavelength
size. Such resonators couple primarily to the magnetic field component of the
incident electromagnetic wave, offering properties suitable for magnetic
meta-atoms. Surprisingly, the relative frequencies of the resonant modes follow
the sequence of the odd numbers, despite the nearly identical boundary
conditions for electromagnetic fields at the extremities of the resonator. In
order to explain the observed spectrum of resonant modes, we show that the
current distribution inside the spiral satisfies a particular Carleman type
singular integral equation. By solving this equation, we obtain a set of
resonant frequencies. The analytically calculated resonance frequencies and the
current distributions are in good agreement with experimental data and the
results of numerical simulations. By using low-temperature laser scanning
microscopy of a superconducting spiral resonator, we compare the experimentally
visualized ac current distributions over the spiral with the calculated ones.
Theory and experiment agree well with each other. Our analytical model allows
for calculation of a detailed three-dimensional magnetic field structure of the
resonators.


title: Long-term variations of geomagnetic activity and their solar sources

abstract:
  Geomagnetic activity in each phase of the solar cycle consists of 3 parts:
(1) a floor below which the geomagnetic activity cannot fall even in the
absence of sunspots, related to moderate graduate commencement storms; (2)
sunspot-related activity due to sudden commencement storms caused by coronal
mass ejections; (3) graduate commencement storms due to high speed solar wind
from solar coronal holes. We find that the changes in the floor depend on the
global magnetic moment of the Sun, and on the other side, from the height of
the floor we can judge about the amplitude of the sunspot cycle.


title:
Phase dependent Andreev spectrum in a difusive SNS junction. Static and
  dynamic current response

abstract:
  A long phase coherent normal (N) wire between superconductors (S) is
characterized by a dense phase dependent Andreev spectrum. We investigate the
current response of Andreev states of an NS ring to a time dependent Aharonov
Bohm flux superimposed to a dc one. The ring is modeled with a tight binding
Hamiltonian including a superconducting region with a BCS coupling between
electron and hole states, in contact with a normal region with on site
disorder. Both dc and ac currents are determined from the computed eigenstates
and energies using a Kubo formula approach. Beside the well known Josephson
current we identify different contributions to the ac response. A low frequency
one related to the dynamics of the thermal occupations of the Andreev states
and a higher frequency one related to microwave induced transitions between
levels. Both are characterized by strongly anharmonic phase dependencies which
are nearly opposite to one another. Our findings are successfully compared to
the results of recent experiments.


title:
Ruler measurements give space-time-transformation-independent invariant
  lengths

abstract:
  Two thought experiments are described in which ruler measurements of spatial
intervals are performed in different reference frames. They demonstrate that
such intervals are frame-independent as well as independent of the nature of
the space-time transformation equations. As explained in detail elsewhere, the
`length contraction' effect of conventional special relativity theory is
therefore spurious and unphysical.


title:
Efficient variational inference for generalized linear mixed models with
  large datasets

abstract:
  The article develops a hybrid Variational Bayes algorithm that combines the
mean-field and fixed-form Variational Bayes methods. The new estimation
algorithm can be used to approximate any posterior without relying on conjugate
priors. We propose a divide and recombine strategy for the analysis of large
datasets, which partitions a large dataset into smaller pieces and then
combines the variational distributions that have been learnt in parallel on
each separate piece using the hybrid Variational Bayes algorithm. The proposed
method is applied to fitting generalized linear mixed models. The computational
efficiency of the parallel and hybrid Variational Bayes algorithm is
demonstrated on several simulated and real datasets.


title:
Speeding up and slowing down the relaxation of a qubit by optimal
  control

abstract:
  We consider a two-level quantum system prepared in an arbitrary initial state
and relaxing to a steady state due to the action of a Markovian dissipative
channel. We study how optimal control can be used for speeding up or slowing
down the relaxation towards the fixed point of the dynamics. We analytically
derive the optimal relaxation times for different quantum channels in the ideal
ansatz of unconstrained quantum control (a magnetic field of infinite
strength). We also analyze the situation in which the control Hamiltonian is
bounded by a finite threshold. As byproducts of our analysis we find that: (i)
if the qubit is initially in a thermal state hotter than the environmental
bath, quantum control cannot speed up its natural cooling rate; (ii) if the
qubit is initially in a thermal state colder than the bath, it can reach the
fixed point of the dynamics in finite time if a strong control field is
applied; (iii) in the presence of unconstrained quantum control it is possible
to keep the evolved state indefinitely and arbitrarily close to special initial
states which are far away from the fixed points of the dynamics.


title: Transition to turbulence in slowly divergent pipe flow

abstract:
  The results of a combined experimental and numerical study of the flow in
slowly diverging pipes are presented. Interestingly, an axisymmetric conical
recirculation cell has been observed. The conditions for its existence and the
length of the cell are simulated for a range of diverging angles and expansion
ratios. There is a critical velocity for the appearance of this state. When the
flow rate increases further, a subcritical transition for localized turbulence
arises. The transition and relaminarization experiments described here quantify
the extent of turbulence. The findings suggest that the transition scenario in
slowly diverging pipes is a combination of stages similar to those observed in
sudden expansions and in straight circular pipe flow.


title:
OH Maser Sources in W49N: Probing Magnetic Field and Differential
  Anisotropic Scattering with Zeeman pairs using the VLBA

abstract:
  Our analysis of a VLBA 12-hour synthesis observation of the OH masers in a
well-known star-forming region W49N has yielded valuable data that enables us
to probe distributions of magnetic fields in both the maser columns and the
intervening interstellar medium (ISM). The data consisting of detailed high
angular-resolution images (with beam-width ~20 milli-arc-seconds) of several
dozen OH maser sources or "spots", at 1612, 1665 and 1667 MHz, reveal
anisotropic scatter broadening, with typical sizes of a few tens of
milli-arc-seconds and axial ratios between 1.5 to 3. Such anisotropies have
been reported earlier by Desai, Gwinn & Diamond (1994) and interpreted as
induced by the local magnetic field parallel to the Galactic plane. However, we
find a) the apparent angular sizes on the average a factor of ~2.5 less than
those reported by Desai et al. (1994), indicating significantly less scattering
than inferred earlier, and b) a significant deviation in the average
orientation of the scatter-broadened images (by ~10 degrees) from that implied
by the magnetic field in the Galactic plane. More intriguingly, for a few
Zeeman pairs in our set, significant differences (up to 6 sigma) are apparent
in the scatter broadened images for the two hands of circular polarization,
even when apparent velocity separation is less than 0.1 km/s. This may possibly
be the first example of a Faraday rotation contribution to the diffractive
effects in the ISM. Using the Zeeman pairs, we also study the distribution of
magnetic field in the W49N complex, finding no significant trend in the spatial
structure function. In this paper, we present the details of our observations
and analysis leading to these findings, discuss implications of our results for
the intervening anisotropic magneto-ionic medium, and suggest the possible
implications for the structure of magnetic fields within this star-forming
region.


title:
IRIDE White Book, An Interdisciplinary Research Infrastructure based on
  Dual Electron linacs&lasers

abstract:
  This report describes the scientific aims and potentials as well as the
preliminary technical design of IRIDE, an innovative tool for
multi-disciplinary investigations in a wide field of scientific, technological
and industrial applications. IRIDE will be a high intensity 'particle factory',
based on a combination of a high duty cycle radio-frequency superconducting
electron linac and of high energy lasers. Conceived to provide unique research
possibilities for particle physics, for condensed matter physics, chemistry and
material science, for structural biology and industrial applications, IRIDE
will open completely new research possibilities and advance our knowledge in
many branches of science and technology. IRIDE will contribute to open new
avenues of discoveries and to address most important riddles: What does matter
consist of? What is the structure of proteins that have a fundamental role in
life processes? What can we learn from protein structure to improve the
treatment of diseases and to design more efficient drugs? But also how does an
electronic chip behave under the effect of radiations? How can the heat flow in
a large heat exchanger be optimized? The scientific potential of IRIDE is far
reaching and justifies the construction of such a large facility in Italy in
synergy with the national research institutes and companies and in the
framework of the European and international research. It will impact also on
R&D work for ILC, FEL, and will be complementarity to other large scale
accelerator projects. IRIDE is also intended to be realized in subsequent
stages of development depending on the assigned priorities.


title:
Distance-regular graphs of $q$-Racah type and the universal Askey-Wilson
  algebra

abstract:
  Let $\C$ denote the field of complex numbers, and fix a nonzero $q \in \C$
such that $q^4 \ne 1$. Define a $\C$-algebra $\Delta_q$ by generators and
relations in the following way. The generators are $A,B,C$. The relations
assert that each of $A+\frac{qBC-q^{-1}CB}{q^2-q^{-2}}$,
$B+\frac{qCA-q^{-1}AC}{q^2-q^{-2}}$, $C+\frac{qAB-q^{-1}BA}{q^2-q^{-2}}$ is
central in $\Delta_q$. The algebra $\Delta_q$ is called the universal
Askey-Wilson algebra. Let $\Gamma$ denote a distance-regular graph that has
$q$-Racah type. Fix a vertex $x$ of $\Gamma$ and let $T=T(x)$ denote the
corresponding subconstituent algebra. In this paper we discuss a relationship
between $\Delta_q$ and $T$. Assuming that every irreducible $T$-module is thin,
we display a surjective $\C$-algebra homomorphism $\Delta_q \to T$. This gives
a $\Delta_q$ action on the standard module of $T$.


title: Higher-order Lorentz violation

abstract:
  This brief review discusses Lorentz-violating operators of arbitrary
dimension within the photon and neutrino sectors of the Standard-Model
Extension.


title:
Short Term Memory Capacity in Networks via the Restricted Isometry
  Property

abstract:
  Cortical networks are hypothesized to rely on transient network activity to
support short term memory (STM). In this paper we study the capacity of
randomly connected recurrent linear networks for performing STM when the input
signals are approximately sparse in some basis. We leverage results from
compressed sensing to provide rigorous non asymptotic recovery guarantees,
quantifying the impact of the input sparsity level, the input sparsity basis,
and the network characteristics on the system capacity. Our analysis
demonstrates that network memory capacities can scale superlinearly with the
number of nodes, and in some situations can achieve STM capacities that are
much larger than the network size. We provide perfect recovery guarantees for
finite sequences and recovery bounds for infinite sequences. The latter
analysis predicts that network STM systems may have an optimal recovery length
that balances errors due to omission and recall mistakes. Furthermore, we show
that the conditions yielding optimal STM capacity can be embodied in several
network topologies, including networks with sparse or dense connectivities.


title: Notes on a Theorem of Benci-Gluck-Ziller-Hayashi

abstract:
  We use constrained variational minimizing methods to study the existence of
periodic solutions with a prescribed energy for a class of second order
Hamiltonian systems with a $C^2$ potential function which may have an unbounded
potential well. Our result can be regarded as complementary to the well-known
theorem of Benci-Gluck-Ziller and Hayashi.


title: Generalization of the hypervirial and Feynman-Hellman theorems

abstract:
  Using well-known methods we generalize (hyper)virial theorems to case of
singular potential. Discussion is carried on for most general second order
differential equation, which involves all physically interesting cases, such as
Schr\"odinger and two-body Klein-Gordon equations with singular potentials.
Some physical consequences are discussed. The connection with Feynman-Hellmann
like theorems are also considered and some relevant differences are underlined.


title:
Connecting Language and Knowledge Bases with Embedding Models for
  Relation Extraction

abstract:
  This paper proposes a novel approach for relation extraction from free text
which is trained to jointly use information from the text and from existing
knowledge. Our model is based on two scoring functions that operate by learning
low-dimensional embeddings of words and of entities and relationships from a
knowledge base. We empirically show on New York Times articles aligned with
Freebase relations that our approach is able to efficiently use the extra
information provided by a large subset of Freebase data (4M entities, 23k
relationships) to improve over existing methods that rely on text features
alone.


title: Image Tag Refinement by Regularized Latent Dirichlet Allocation

abstract:
  Tagging is nowadays the most prevalent and practical way to make images
searchable. However, in reality many manually-assigned tags are irrelevant to
image content and hence are not reliable for applications. A lot of recent
efforts have been conducted to refine image tags. In this paper, we propose to
do tag refinement from the angle of topic modeling and present a novel
graphical model, regularized Latent Dirichlet Allocation (rLDA). In the
proposed approach, tag similarity and tag relevance are jointly estimated in an
iterative manner, so that they can benefit from each other, and the multi-wise
relationships among tags are explored. Moreover, both the statistics of tags
and visual affinities of images in the corpus are explored to help topic
modeling. We also analyze the superiority of our approach from the deep
structure perspective. The experiments on tag ranking and image retrieval
demonstrate the advantages of the proposed method.


title: On the existence of moments for high dimensional importance sampling

abstract:
  Theoretical results for importance sampling rely on the existence of certain
moments of the importance weights, which are the ratios between the proposal
and target densities. In particular, a finite variance ensures square root
convergence and asymptotic normality of the importance sampling estimate, and
can be important for the reliability of the method in practice. We derive
conditions for the existence of any required moments of the weights for
Gaussian proposals and show that these conditions are almost necessary and
sufficient for a wide range of models with latent Gaussian components.
Important examples are time series and panel data models with measurement
densities which belong to the exponential family. We introduce practical and
simple methods for checking and imposing the conditions for the existence of
the desired moments. We develop a two component mixture proposal that allows us
to flexibly adapt a given proposal density into a robust importance density.
These methods are illustrated on a wide range of models including generalized
linear mixed models, non-Gaussian nonlinear state space models and panel data
models with autoregressive random effects.


title: Node-Initiated Byzantine Consensus Without a Common Clock

abstract:
  The majority of the literature on consensus assumes that protocols are
jointly started at all nodes of the distributed system. We show how to remove
this problematic assumption in semi-synchronous systems, where messages delays
and relative drifts of local clocks may vary arbitrarily within known bounds.
Our framework is self-stabilizing and efficient both in terms of communication
and time; more concretely, compared to a synchronous start in a synchronous
model of a non-self-stabilizing protocol, we achieve a constant-factor increase
in the time and communicated bits to complete an instance, plus an additive
communication overhead of O(n log n) broadcasted bits per time unit and node.
The latter can be further reduced, at an additive increase in time complexity.


title:
Modified gravity with logarithmic curvature corrections and the
  structure of relativistic stars

abstract:
  We consider the effect of a logarithmic f(R) theory, motivated by the form of
the one-loop effective action arising from gluons in curved spacetime, on the
structure of relativistic stars. In addition to analysing the consistency
constraints on the potential of the scalar degree of freedom, we discuss the
possibility of observational features arising from a fifth force in the
vicinity of the neutron star surface. We find that the model exhibits a
chameleon effect that completely suppresses the effect of the modification on
scales exceeding a few radii, but close to the surface of the neutron star, the
deviation from General Relativity can significantly affect the surface redshift
that determines the shift in absorption (or emission) lines. We also use the
method of perturbative constraints to solve the modified
Tolman-Oppenheimer-Volkov equations for normal and self-bound neutron stars
(quark stars).


title:
Beginning of activity in 67P/Churyumov-Gerasimenko and predictions for
  2014/5

abstract:
  Comet 67P/Churyumov-Gerasimenko was selected in 2003 as the new target of the
Rosetta mission. It has since been the subject of a detailed campaign of
observations to characterise its nucleus and activity. Here we present
previously unpublished data taken around the start of activity of the comet in
2007/8, before its last perihelion passage. We constrain the time of the start
of activity, and combine this with other data taken throughout the comet's
orbit to make predictions for its likely behaviour during 2014/5 while Rosetta
is operating. A considerable difficulty in observing 67P during the past years
has been its position against crowded fields towards the Galactic centre for
much of the time. The 2007/8 data presented here were particularly difficult,
and the comet will once again be badly placed for Earth-based observations in
2014/5. We make use of the difference image analysis (DIA) technique, which is
commonly used in variable star and exoplanet research, to remove background
sources and extract images of the comet. In addition, we reprocess a large
quantity of archival images of 67P covering its full orbit, to produce a
heliocentric lightcurve. By using consistent reduction, measurement and
calibration techniques we generate a remarkably clean lightcurve, which can be
used to measure a brightness-distance relationship and to predict the future
brightness of the comet. We determine that the comet was active around November
2007, at a pre-perihelion distance from the Sun of 4.3 AU. The comet will reach
this distance, and probably become active again, in March 2014. We find that
the dust brightness can be well described by Af\rho \propto r^-3.2
pre-perihelion and r^-3.4 post-perihelion, and that the comet has a higher
dust-to-gas ratio than average. A model fit to the photometric data suggests
that only a small fraction (1.4%) of the surface is active.


title: A survey on stability and rigidity results for Lie algebras

abstract:
  We give simple and unified proofs of the known stability and rigidity results
for Lie algebras, Lie subalgebras and Lie algebra homomorphisms. Moreover, we
investigate when a Lie algebra homomorphism is stable under all automorphisms
of the codomain (including outer automorphisms).


title:
Semi analytical description of formation of galaxies and clusters of
  galaxies

abstract:
  We apply the well known semi analytical model of formation of DM halos to
discuss the process of formation and evolution of the relaxed objects dominated
by the DM component (such as the first and dSph galaxies and clusters of
galaxies). On the one hand this approach allows us to obtain a simple
description of evolution of the first galaxies. On the other hand it reveals
links between the observed characteristics of the relaxed DM halos and the
initial power spectrum of density perturbations. Results of our analysis of the
observed properties of 41 DM dominated dSph galaxies and data of $\sim 300$
clusters of galaxies are consistent with the $\Lambda$CDM like power spectrum
of initial perturbations down to the scale of $\sim 10kpc$.


title: Likelihood-ratio calibration using prior-weighted proper scoring rules

abstract:
  Prior-weighted logistic regression has become a standard tool for calibration
in speaker recognition. Logistic regression is the optimization of the expected
value of the logarithmic scoring rule. We generalize this via a parametric
family of proper scoring rules. Our theoretical analysis shows how different
members of this family induce different relative weightings over a spectrum of
applications of which the decision thresholds range from low to high. Special
attention is given to the interaction between prior weighting and proper
scoring rule parameters. Experiments on NIST SRE'12 suggest that for
applications with low false-alarm rate requirements, scoring rules tailored to
emphasize higher score thresholds may give better accuracy than logistic
regression.


title:
Flavor Pairing in Medieval European Cuisine: A Study in Cooking with
  Dirty Data

abstract:
  An important part of cooking with computers is using statistical methods to
create new, flavorful ingredient combinations. The flavor pairing hypothesis
states that culinary ingredients with common chemical flavor components combine
well to produce pleasant dishes. It has been recently shown that this design
principle is a basis for modern Western cuisine and is reversed for Asian
cuisine.
  Such data-driven analysis compares the chemistry of ingredients to ingredient
sets found in recipes. However, analytics-based generation of novel flavor
profiles can only be as good as the underlying chemical and recipe data.
Incomplete, inaccurate, and irrelevant data may degrade flavor pairing
inferences. Chemical data on flavor compounds is incomplete due to the nature
of the experiments that must be conducted to obtain it. Recipe data may have
issues due to text parsing errors, imprecision in textual descriptions of
ingredients, and the fact that the same ingredient may be known by different
names in different recipes. Moreover, the process of matching ingredients in
chemical data and recipe data may be fraught with mistakes. Much of the
`dirtiness' of the data cannot be cleansed even with manual curation.
  In this work, we collect a new data set of recipes from Medieval Europe
before the Columbian Exchange and investigate the flavor pairing hypothesis
historically. To investigate the role of data incompleteness and error as part
of this hypothesis testing, we use two separate chemical compound data sets
with different levels of cleanliness. Notably, the different data sets give
conflicting conclusions about the flavor pairing hypothesis in Medieval Europe.
As a contribution towards social science, we obtain inferences about the
evolution of culinary arts when many new ingredients are suddenly made
available.

categories: physics.soc-ph cs.CY cs.SI physics.data-an


title: High energy gamma-ray constraints on decaying Dark Matter

abstract:
  New bounds on decaying Dark Matter are derived from the gamma-ray
measurements of (i) the isotropic residual (extragalactic) background by Fermi
and (ii) the Fornax galaxy cluster by H.E.S.S. We find that those from (i) are
among the most stringent constraints currently available, for a large range of
dark matter masses and a variety of decay modes, excluding half-lives up to
about 10^26 to few 10^27 seconds. In particular, they rule out the
interpretation in terms of decaying dark matter of the e+/- spectral features
in PAMELA, Fermi and H.E.S.S., unless very conservative choices are adopted. We
also discuss future prospects for CTA bounds from Fornax which, contrary to the
present H.E.S.S. constraints of (ii), may allow for an interesting improvement
and may become better than those from the current or future extragalactic Fermi
data.


title: Fluffy dust forms icy planetesimals by static compression

abstract:
  Context: In planetesimal formation theory, several barriers have been
proposed, which are bouncing, fragmentation, and radial drift problems. To
understand the structure evolution of dust aggregates is a key in the
planetesimal formation. Dust grains become fluffy by coagulation in
protoplanetary disks. However, once they become fluffy, they are not
sufficiently compressed by collisional compression to form compact
planetesimals. Aims: We aim to reveal the pathway of the dust structure
evolution from dust grains to compact planetesimals. Methods: Using the
compressive strength formula, we analytically investigate how fluffy dust
aggregates are compressed by static compression due to ram pressure of the disk
gas and self gravity of the aggregates in protoplanetary disks. Results: We
reveal the pathway of the porosity evolution from dust grains via fluffy
aggregates to form planetesimals, circumventing the barriers in planetesimal
formation. The aggregates are compressed by the disk gas to the density of
10^{-3} g/cm^3 in coagulation, which is more compact than the case with
collisional compression. Then, they are compressed more by self gravity to
10^{-1} g/cm^3 when the radius is 10 km. Although the gas compression
decelerate the growth, they grow enough rapidly to avoid the radial drift
barrier when the orbital radius is < 6 AU in a typical disk. Conclusions: We
propose fluffy dust growth scenario from grains to planetesimals. It enables
the icy planetesimal formation in a wide range beyond the snowline in
protoplanetary disks. This result proposes a concrete initial condition of
planetesimals for the later stages of the planet formation.


title:
On $q$-Analogs of Some Families of Multiple Harmonic Sum and Multiple
  Zeta Star Value Identities

abstract:
  In recent years, there has been intensive research on the ${\mathbb
Q}$-linear relations between multiple zeta (star) values. In this paper, we
prove many families of identities involving the $q$-analog of these values,
from which we can always recover the corresponding classical identities by
taking $q\to 1$. The main result of the paper is the duality relations between
multiple zeta star values and Euler sums and their $q$-analogs, which are
generalizations of the Two-one formula and some multiple harmonic sum
identities and their $q$-analogs proved by the authors recently. Such duality
relations lead to a proof of the conjecture by Ihara et al. that the Hoffman
$\star$-elements $\zeta^{\star}(s_1,\dots,s_r)$ with $s_i\in\{2,3\}$ span the
vector space generated by multiple zeta values over ${\mathbb Q}$.


title: Frieze patterns as root posets and affine triangulations

abstract:
  The entries of frieze patterns may be interpreted as coordinates of roots of
a finite Weyl groupoid of rank two. We prove the existence of maximal elements
in their root posets and classify those frieze patterns which can be used to
build an affine simplicial arrangement.


title:
Giant Faraday rotation induced by Berry phase in bilayer graphene under
  strong terahertz fields

abstract:
  High-order terahertz (THz) sideband generation (HSG) in semiconductors is a
phenomenon with physics similar to high-order harmonic generation but in a much
lower frequency regime. It was found that the electron-hole pairs excited by a
weak optical laser can accumulate Berry phases along a cyclic path under the
driving of a strong THz field. The Berry phases appear as the Faraday rotation
angles of the emission signal under short-pulse excitation in monolayer
MoS$_2$. In this paper, the theory of Berry phase in THz extreme nonlinear
optics is applied to biased bilayer graphene with Bernal stacking, which has
similar Bloch band features and optical properties to the monolayer MoS$_2$,
such as time-reversal related valleys and valley contrasting optical selection
rules. The bilayer graphene has much larger Berry curvature than monolayer
MoS$_2$, which leads to a giant Faraday rotation of the optical emission
($\sim$ 1 rad for a THz field with frequency 1 THz and strength 8 kV/cm). This
provides opportunities to use bilayer graphene and low-power THz lasers for
ultrafast electro-optical devices.


title: Pathways to relativistic curved momentum spaces: de Sitter case study

abstract:
  Several arguments suggest that the Planck scale could be the characteristic
scale of curvature of momentum space. As other recent studies we assume that
the metric of momentum space determines the condition of on-shellness while the
momentum-space affine connection governs the form of the law of composition of
momenta. We show that the possible choices of laws of composition of momenta
are more numerous than the possible choices of affine connection on a momentum
space. This motivates us to propose a new prescription for associating an
affine connection to momentum composition, which we compare to the one most
used in the recent literature. We find that the two prescriptions lead to the
same picture of the so-called $\kappa$-momentum space, with de Sitter metric
and $\kappa$-Poincar\'e connection. We also examine in greater detail than ever
before the DSR-relativistic properties of $\kappa$-momentum space, particularly
in relation to its noncommutative law of composition of momenta. We then show
that in the case of "proper de Sitter momentum space", with the de Sitter
metric and its Levi-Civita connection, the two prescriptions are inequivalent.
Our novel prescription leads to a picture of proper de Sitter momentum space
which is DSR-relativistic and is characterized by a commutative law of
composition of momenta, a possibility for which no explicit
curved-momentum-space picture had been previously found. We argue that our
construction provides a natural test case for the study of momentum spaces with
commutative, and yet deformed, laws of composition of momenta. Moreover, it can
serve as laboratory for the exploration of the properties of DSR-relativistic
theories which are not connected to group-manifold momentum spaces and Hopf
algebras.


title: Ontological models, preparation contextuality and nonlocality

abstract:
  The ontological model framework for an operational theory has generated much
interest in recent years. The debate concerning reality of quantum states has
been made more precise in this framework. With the introduction of generalized
notion of contextuality in this framework, it has been shown that completely
mixed state of a qubit is \emph{preparation contextual}. Interestingly, this
new idea of preparation contextuality has been used to demonstrate nonlocality
of some $\psi$-epistemic models without any use of Bell's inequality. In
particular, nonlocality of a non maximally $\psi$-epistemic model has been
demonstrated from preparation contextuality of a maximally mixed qubit and
Schr\"{o}dinger's steerability of the maximally entangled state of two qubits
[Phys. Rev. Lett {\bf 110}, 120401 (2013)]. In this paper, we, show that any
mixed state is preparation contextual. We, then, show that nonlocality of any
bipartite pure entangled state, with Schmidt rank two, follows from preparation
contextuality and steerability provided we impose certain condition on the
epistemicity of the underlying ontological model. More interestingly, if the
pure entangled state is of Schmidt rank greater than two, its nonlocality
follows without any further condition on the epistemicity. Thus our result
establishes a stronger connection between nonlocality and preparation
contextuality by revealing nonlocality of any bipartite pure entangled states
without any use of Bell-type inequality.


title: Mixing for continuous time dynamical systems with infinite measure

abstract:
  We develop operator renewal theory for flows and apply this to infinite
ergodic theory. In particular we obtain results on mixing for a large class of
infinite measure semiflows.
  Examples of systems covered by our results include suspensions over parabolic
rational maps of the complex plane, and nonuniformly expanding semiflows with
indifferent periodic orbits. In some cases, we obtain higher order asymptotics
and rates of mixing.


title:
How cosmic-ray electron propagation affects radio-far-infrared
  correlations in M31 and M33

abstract:
  We investigate the effect of propagation of cosmic-ray electrons (CRE) on the
nonthermal (synchrotron) - far-infrared correlations in M31 and M33. The
thermal (TH) and nonthermal (NTH) emission components of the radio continuum
emission at 1.4 GHz and one higher frequency are compared with dust emission
from M31 and M33 using Spitzer data. In both galaxies the TH emission is
linearly correlated with the emission from warm dust (24 \mu m, 70 \mu m), but
the power laws of the NTH-FIR correlations have exponents b < 1 that increase
with increasing frequency. Furthermore, the values of b for M33 are
significantly smaller (b ~ 0.4) than those for M31 (b ~ 0.6). We interpret the
differences in b as differences in the diffusion length of the CRE. We estimate
the diffusion length in two ways: (1) by smoothing the NTH emission at the
higher frequency until the correlation with NTH emission at 1.4 GHz has b = 1,
and (2) by smoothing the TH emission until the correlation with the NTH
emission at the same frequency has b = 1, assuming that the TH emission
represents the source distribution of the CRE. Our smoothing experiments show
that M31 only has a thin NTH disk with a scale height of h = 0.3-0.4 kpc at 1.4
GHz, whereas M33 has a similar thin disk as well as a thick disk with scale
height h_thick ~ 2 kpc. In the thin disks, the (deprojected) diffusion length
at 1.4 GHz is ~ 1.5 kpc, yielding a diffusion coefficient of ~ 2 10^28 cm^2/s.
The structure, strength and regularity of the magnetic field in a galaxy as
well as the existence of a thick disk determine the diffusion of the CRE, and
hence, the power-law exponent of the NTH-FIR correlations.


title:
Spin filtering and entanglement detection due to spin-orbit interaction
  in carbon nanotube cross-junctions

abstract:
  We demonstrate that due to their spin-orbit interaction carbon nanotube
cross-junctions have attractive spin projective properties for transport.
First, we show that the junction can be used as a versatile spin filter as a
function of a backgate and a static external magnetic field. Switching between
opposite spin filter directions can be achieved by small changes of the
backgate potential, and a full polarization is generically obtained in an
energy range close to the Dirac points. Second, we discuss how the spin
filtering properties affect the noise correlators of entangled electron pairs,
which allows us to obtain signatures of the type of entanglement that are
different from the signatures in conventional semiconductor cross-junctions.


title:
Sharp Threshold for Multivariate Multi-Response Linear Regression via
  Block Regularized Lasso

abstract:
  In this paper, we investigate a multivariate multi-response (MVMR) linear
regression problem, which contains multiple linear regression models with
differently distributed design matrices, and different regression and output
vectors. The goal is to recover the support union of all regression vectors
using $l_1/l_2$-regularized Lasso. We characterize sufficient and necessary
conditions on sample complexity \emph{as a sharp threshold} to guarantee
successful recovery of the support union. Namely, if the sample size is above
the threshold, then $l_1/l_2$-regularized Lasso correctly recovers the support
union; and if the sample size is below the threshold, $l_1/l_2$-regularized
Lasso fails to recover the support union. In particular, the threshold
precisely captures the impact of the sparsity of regression vectors and the
statistical properties of the design matrices on sample complexity. Therefore,
the threshold function also captures the advantages of joint support union
recovery using multi-task Lasso over individual support recovery using
single-task Lasso.


title: The homology graph of a higher dimensional automaton

abstract:
  Higher dimensional automata, i.e. labelled precubical sets, model concurrent
systems. We introduce the homology graph of an HDA, which is a directed graph
whose nodes are the homology classes of the HDA. We show that the homology
graph is invariant under homeomorphic abstraction, i.e. under weak morphisms
that are homeomorphisms.


title: Nucleon and flavor form factors in a light front quark model in AdS/QCD

abstract:
  Using the light front wave functions for the nucleons in a quark model in
AdS/QCD, we calculate the nucleon electromagnetic form factors. The flavor
decompositions of the nucleon form factors are calculated from the GPDs in this
model. We show that the nucleon form factors and their flavor decompositions
calculated in AdS/QCD are in agreement with experimental data.


title: Massive binaries in the vicinity of Sgr A*

abstract:
  A long-term spectroscopic and photometric survey of the most luminous and
massive stars in the vicinity of the super-massive black hole Sgr A* revealed
two new binaries; a long-period Ofpe/WN9 binary, GCIRS 16NE, with a modest
eccentricity of 0.3 and a period of 224 days and an eclipsing Wolf-Rayet binary
with a period of 2.3 days. Together with the already identified binary GCIRS
16SW, there are now three confirmed OB/WR binaries in the inner 0.2\,pc of the
Galactic Center. Using radial velocity change upper limits, we were able to
constrain the spectroscopic binary fraction in the Galactic Center to $F_{\rm
SB}=0.27^{+0.29}_{-0.19}$ at a confidence level of 95%, a massive binary
fraction similar to that observed in dense clusters. The fraction of eclipsing
binaries with photometric amplitudes $\Delta m>0.4$ is $F^{\rm GC}_{\rm
EB}=3\pm2%$, which is consistent with local OB star clusters ($F_{\rm EB}=1%$).
Overall the Galactic Center binary fraction seems to be close to the binary
fraction in comparable young clusters.


title: Crepant resolutions of Weierstrass threefolds and non-Kodaira fibres

abstract:
  In this paper we want to study the non-Kodaira fibres in a smooth
equidimensional elliptic threefold. If the morphism to the Weierstrass model of
the fibration is crepant, then we can locate the non-Kodaira fibres and give a
description of their structure. In particular, they lie over the singular
points of the (reduced) discriminant of the fibration and are contraction of a
Kodaira fibre, whose type can be predicted using Tate's algorithm.


title: Topologically Distinct Lagrangian and Symplectic Fillings

abstract:
  We construct infinitely many Legendrian links in the standard contact
$\mathbb{R}^3$ with arbitrarily many topologically distinct Lagrangian
fillings. The construction is used to find links in $S^3$ that bound
topologically distinct pieces of algebraic curves in $B^4 \subset
\mathbb{C}^2$, is applied to find contact 3-manifolds with topologically
distinct symplectic fillings, and is generalized to higher dimensions.


title:
Light staus and enhanced Higgs diphoton rate with non-universal gaugino
  masses and SO(10) Yukawa unification

abstract:
  It is shown that substantially enhanced Higgs to diphoton rate induced by
light staus with large left-right mixing in MSSM requires at the GUT scale
non-universal gaugino masses with bino and/or wino lighter than gluino. The
possibility of such enhancement is investigated in MSSM models with arbitrary
gaugino masses at the GUT scale with additional restriction of top-bottom-tau
Yukawa unification, as predicted by minimal SO(10) GUTs. Many patterns of
gaugino masses leading to enhanced Higgs to diphoton rate and the Yukawa
unification are identified. Some of these patterns can be accommodated in a
well-motivated scenarios such as mirage mediation or SUSY breaking F-terms
being a non-singlet of SO(10). Phenomenological implications of a scenario with
non-universal gaugino masses generated by a mixture of the singlet F-term and
the F-term in a 24-dimensional representation of SU(5) $\subset$ SO(10) are
studied in detail. Possible non-universalities of other soft terms generated by
such F-terms are discussed. The enhancement of Higgs to diphoton rate up to 30%
can be obtained in agreement with all phenomenological constraints, including
vacuum metastability bounds. The lightest sbottom and pseudoscalar Higgs are
within easy reach of the 14 TeV LHC. The LSP can be either bino-like or
wino-like. The thermal relic abundance in the former case may be in agreement
with the cosmological data thanks to efficient stau coannihilation.


title: On rotation of complex structures

abstract:
  We put in a general framework the situations in which a Riemannian manifold
admits a family of compatible complex structures, including hyperkahler metrics
and the Spin-rotations of arxiv:1302.2846. We determine the (polystable)
holomorphic bundles which are rotable, i.e., they remain holomorphic when we
change a complex structure by a different one in the family.


title:
Non-Adiabatic Universal Holonomic Quantum Gates Based on Abelian
  Holonomies

abstract:
  We implement a non-adiabatic universal set of holonomic quantum gates based
on abelian holonomies using dynamical invariants, by Lie-algebraic methods.
Unlike previous implementations, presented scheme does not rely on secondary
methods such as double-loop or spin-echo and avoids associated experimental
difficulties. It turns out that such gates exist purely in the non-adiabatic
regime for these systems.


title: Periodic Solutions of Non-Autonomous Second Order Hamiltonian Systems

abstract:
  We try to generalize a result of M. Willem on forced periodic oscillations
which required the assumption that the forced potential is periodic on spatial
variables. In this paper, we only assume its integral on the time variable is
periodic, and so we extend the result to cover the forced pendulum equation. We
apply the direct variational minimizing method and Rabinowtz's saddle point
theorem to study the periodic solution when the integral of the potential on
the time variable is periodic.


title:
Galois representations and torsion in the coherent cohomology of Hilbert
  modular varieties

abstract:
  Let $F$ be a totally real number field and let $p$ be a prime unramified in
$F$. We prove the existence of Galois pseudo-representations attached to mod
$p^m$ Hecke eigenclasses of paritious weight occurring in the coherent
cohomology of Hilbert modular varieties for $F$ of level prime to $p$.


title: On VC-minimal fields and dp-smallness

abstract:
  In this paper, we show that VC-minimal ordered fields are real closed. We
introduce a notion, strictly between convexly orderable and dp-minimal, that we
call dp-small, and show that this is enough to characterize many algebraic
theories. For example, dp-small ordered groups are abelian divisible and
dp-small ordered fields are real closed.


title:
Long-term variations of solar magnetic fields derived from geomagnetic
  data

abstract:
  Sunspots are dark spots on the solar surface associated with strong magnetic
fields. The number, area, and brightness of sunspots are supposed to reflect
the intensity of the solar magnetic fields and are often used as proxies for
their long-term variations. However, the correlations between the sunspot
parameters and solar magnetic fields are not constant, and the causes and the
time profiles of the variations in these correlations are not quite clear.
Therefore, the sunspot data alone cannot be used as proxy for deriving the
variations of the sunspot magnetic fields for periods when no instrumental
measurements are available. But the Earth is a sort of a probe reacting to
interplanetary disturbances which are manifestation of the solar magnetic
fields, so records of the geomagnetic activity can be used as diagnostic tools
for reconstructing past solar magnetic fields evolution. In the present study
we combine sunspot and geomagnetic data to estimate the long-term variations of
sunspot magnetic fields.


title: Weight modules of D(2,1,a)

abstract:
  A weight module of a basic Lie superalgebra is called finite if all of its
weight spaces are finite dimensional, and it is called bounded if there is a
uniform bound on the dimension of a weight space. The minimum bound is called
the degree of the module. For the basic Lie superalgebra D(2,1,a), we prove
that every simple weight module is bounded and has degree less than or equal to
8. This bound is attained by a cuspidal module if and only if it is "typical".
Atypical cuspidal modules have degree less than or equal to 6 and greater than
or equal to 2.


title:
Classical-Quantum Arbitrarily Varying Wiretap Channel: Ahlswede
  dichotomy, Positivity, Resources, Super Activation

abstract:
  We establish Ahlswede dichotomy for arbitrarily varying classical-quantum
wiretap channels. This means that either the deterministic secrecy capacity of
an arbitrarily varying classical-quantum wiretap channel is zero or it equals
its randomness-assisted secrecy capacity. We analyze the secrecy capacity of
arbitrarily varying classical-quantum wiretap channels when the sender and the
receiver use various resources. It turns out that having randomness, common
randomness, and correlation as resources are very helpful for achieving a
positive deterministic secrecy capacity of arbitrarily varying
classical-quantum wiretap channels. We prove the phenomenon super-activation
for arbitrarily varying classical-quantum wiretap channels, i.e., if we use two
arbitrarily varying classical-quantum wiretap channels, both with zero
deterministic secrecy capacity together, they allow perfect secure
transmission.


title:
Electronic transport through molecular transistors in the polaronic
  regime

abstract:
  In this work, a new theoretical approach to study the non-equilibrium
transport properties of nanoscale systems coupled to metallic electrodes with
strong electron-phonon interactions is presented. The proposed approach
consists in a resummation of the dominant Feynman diagrams from the exact
preturbative expansion. This scheme is compared with methods that can be found
in the literature. It shows a good agreement with these methods in the range
where they are known to provide good results, for a wide range of parameters.
Also, it is compared with path-integral Monte Carlo calculations giving a
relatively good agreement for polaronic and non polaronic regimes. Some
preliminary results for the current noise obtained with our method are
presented.


title:
Quantum Fisher Information of Entangled Coherent States in a Lossy
  Mach-Zehnder Interferometer

abstract:
  We give an analytical result for the quantum Fisher information of entangled
coherent States in a lossy Mach-Zehnder Interferometer recently proposed by J.
Joo et al. [Phys. Rev. Lett. 107, 083601(2011)]. For small loss of photons, we
find that the entangled coherent state can surpass the Heisenberg limit.
Furthermore, The formalism developed here is applicable to the study of phase
sensitivity of multipartite entangled coherent states.


title:
Designer thermal switches: Effect of the contact material on
  instantaneous thermoelectric transport through a strongly interacting quantum
  dot

abstract:
  We investigate the effect of contact geometry on the instantaneous
thermoelectric response of a quantum dot pushed suddenly into the Kondo regime
via a gate voltage using time dependent non-crossing approximation and linear
response Onsager relations. We utilize graphene and metal contacts for this
purpose. Instantaneous thermopower displays sinusoidal oscillations whose
frequency is proportional to the energy separation between the van Hove
singularity in the contact density of states and Fermi level for both cases
regardless of the asymmetry factor at the onset of Kondo timescale. The
amplitude of the oscillations increases with decreasing temperature saturating
around the Kondo temperature. We also calculate the instantaneous figure of
merit and show that the oscillations taking place at temperatures above the
Kondo temperature are enhanced more than the ones occurring at lower
temperatures due to the violation of the Wiedemann-Franz law. Graphene emerges
as a more promising electrode candidate than ordinary metals in single electron
devices since it can minimize these oscillations.


title: Baryogenesis and Dark Matter with Vector-like Fermions

abstract:
  We show that vector-like fermions can act as the dark matter candidate in the
universe whilst also playing a crucial role in electroweak baryogenesis through
contributing to the barrier in the one-loop thermal scalar potential. In order
for the new fermions to give rise to a strong first order phase transition, we
show that one requires rather large Yukawa couplings in the new sector, which
are strongly constrained by electroweak precision tests and perturbativity.
Strong couplings between the dark matter candidate and the Higgs boson
intuitively lead to small values of the relic density and problems with dark
matter direct detection bounds. Nevertheless, when considering the most general
realisation of the model, we find regions in the parameter space that respect
all current constraints and may explain both mysteries simultaneously.


title:
A Study on Classification in Imbalanced and Partially-Labelled Data
  Streams

abstract:
  The domain of radio astronomy is currently facing significant computational
challenges, foremost amongst which are those posed by the development of the
world's largest radio telescope, the Square Kilometre Array (SKA). Preliminary
specifications for this instrument suggest that the final design will
incorporate between 2000 and 3000 individual 15 metre receiving dishes, which
together can be expected to produce a data rate of many TB/s. Given such a high
data rate, it becomes crucial to consider how this information will be
processed and stored to maximise its scientific utility. In this paper, we
consider one possible data processing scenario for the SKA, for the purposes of
an all-sky pulsar survey. In particular we treat the selection of promising
signals from the SKA processing pipeline as a data stream classification
problem. We consider the feasibility of classifying signals that arrive via an
unlabelled and heavily class imbalanced data stream, using currently available
algorithms and frameworks. Our results indicate that existing stream learners
exhibit unacceptably low recall on real astronomical data when used in standard
configuration; however, good false positive performance and comparable accuracy
to static learners, suggests they have definite potential as an on-line
solution to this particular big data challenge.


title: Characterizing Data Analysis Workloads in Data Centers

abstract:
  As the amount of data explodes rapidly, more and more corporations are using
data centers to make effective decisions and gain a competitive edge. Data
analysis applications play a significant role in data centers, and hence it has
became increasingly important to understand their behaviors in order to further
improve the performance of data center computer systems. In this paper, after
investigating three most important application domains in terms of page views
and daily visitors, we choose eleven representative data analysis workloads and
characterize their micro-architectural characteristics by using hardware
performance counters, in order to understand the impacts and implications of
data analysis workloads on the systems equipped with modern superscalar
out-of-order processors. Our study on the workloads reveals that data analysis
applications share many inherent characteristics, which place them in a
different class from desktop (SPEC CPU2006), HPC (HPCC), and service workloads,
including traditional server workloads (SPECweb2005) and scale-out service
workloads (four among six benchmarks in CloudSuite), and accordingly we give
several recommendations for architecture and system optimizations. On the basis
of our workload characterization work, we released a benchmark suite named
DCBench for typical datacenter workloads, including data analysis and service
workloads, with an open-source license on our project home page on
http://prof.ict.ac.cn/DCBench. We hope that DCBench is helpful for performing
architecture and small-to-medium scale system researches for datacenter
computing.


title: Ancient west Eurasian ancestry in southern and eastern Africa

abstract:
  The history of southern Africa involved interactions between indigenous
hunter-gatherers and a range of populations that moved into the region. Here we
use genome-wide genetic data to show that there are at least two admixture
events in the history of Khoisan populations (southern African hunter-gatherers
and pastoralists who speak non-Bantu languages with click consonants). One
involved populations related to Niger-Congo-speaking African populations, and
the other introduced ancestry most closely related to west Eurasian (European
or Middle Eastern) populations. We date this latter admixture event to
approximately 900-1,800 years ago, and show that it had the largest demographic
impact in Khoisan populations that speak Khoe-Kwadi languages. A similar signal
of west Eurasian ancestry is present throughout eastern Africa. In particular,
we also find evidence for two admixture events in the history of Kenyan,
Tanzanian, and Ethiopian populations, the earlier of which involved populations
related to west Eurasians and which we date to approximately 2,700 - 3,300
years ago. We reconstruct the allele frequencies of the putative west Eurasian
population in eastern Africa, and show that this population is a good proxy for
the west Eurasian ancestry in southern Africa. The most parsimonious
explanation for these findings is that west Eurasian ancestry entered southern
Africa indirectly through eastern Africa.


title: Boundary concentration of a Gauged Nonlinear Schrodinger Equation

abstract:
  This paper is motivated by a gauged Schrodinger equation in dimension 2
including the so-called Chern-Simons term. The radially symmetric case leads to
an elliptic problem with a nonlocal defocusing term, in competition with a
local focusing nonlinearity. In this work we pose the equations in a ball under
homogeneous Dirichlet boundary conditions. By using singular perturbation
arguments we prove existence of solutions for large values of the radius. Those
solutions are located close to the boundary and the limit profile is given.


title: Random Field XY Model in Three Dimensions: The Role of Vortices

abstract:
  We study vortex states in a 3d random-field XY model of up to one billion
lattice spins. Starting with random spin orientations, the sample freezes into
the vortex-glass state with a stretched-exponential decay of spin correlations,
having short correlation length and a low susceptibility, compared to
vortex-free states. In a field opposite to the initial magnetization, peculiar
topological objects -- walls of spins still opposite to the field -- emerge
along the hysteresis curve. On increasing the field strength, the walls develop
cracks bounded by vortex loops. The loops then grow in size and eat the walls
away. Applications to magnets and superconductors are discussed.


title:
Analysis of the volatiles in the headspace above the plasmodium and
  sporangia of the slime mould (Physarum polycephalum) by SPME-GCMS

abstract:
  Solid phase micro-extraction (SPME) coupled with Gas Chromatography Mass
Spectrometry (GC-MS) was used to extract and analyse the volatiles in the
headspace above the plasmodial and sporulating stages of the slime mould
Physarum Polycephalum. In total 115 compounds were identified from across a
broad range of chemical classes. Although more (87) volatile organic compounds
(VOCs) were identified when using a higher incubation temperature of 75oC, a
large number of compounds (79) were still identified at the lower extraction
temperature of 30oC and where the plasmodial stage was living. Far fewer
compounds were extracted after sporulation at the two extraction temperatures.
There were some marked differences between the VOCs identified in the
plasmodial stage and after sporulation. In particular the nitrogen containing
compounds acetonitrile, pyrrole, 2, 5-dimethyl-pyrazine and trimethyl pyrazine
seemed to be associated with the sporulating stage. There were many compounds
associated predominantly with the plasmodial stage including a number of furans
and alkanes. Interestingly, a number of known fungal metabolites were
identified including 1-octen-3-ol, 3-octanone, 1-octen-3-one, 3-octanol. In
addition known metabolites of cyanobacteria and actinobacteria in particular
geosmin was identified in the headspace. Volatile metabolites that had
previously been identified as having a positive chemotactic response to the
plasmodial stage of P. polycephalum were also identified including
{\beta}-farnesene, {\beta}-myrcene, limonene and 3-octanone. This study
constitutes the first comprehensive analysis of the headspace volatiles emitted
from Physarum Polycephalum. Further work to understand the origin and function
of the volatiles identified is required.


title:
Extreme variability in convergence to structural balance in frustrated
  dynamical systems

abstract:
  In many complex systems, the dynamical evolution of the different components
can result in adaptation of the connections between them. We consider the
problem of how a fully connected network of discrete-state dynamical elements
which can interact via positive or negative links, approaches structural
balance by evolving its links to be consistent with the states of its
components. The adaptation process, inspired by Hebb's principle, involves the
interaction strengths evolving in accordance with the dynamical states of the
elements. We observe that in the presence of stochastic fluctuations in the
dynamics of the components, the system can exhibit large dispersion in the time
required for converging to the balanced state. This variability is
characterized by a bimodal distribution, which points to an intriguing
non-trivial problem in the study of evolving energy landscapes.


title:
Incorporation of Polar Mellin Transform in a Hybrid Optoelectronic
  Correlator for Scale & Rotation Invariant Target Recognition

abstract:
  In this paper, we show that our proposed hybrid optoelectronic correlator
(HOC), which correlates images using spatial light modulators (SLM), detectors
and field programmable gate arrays (FPGAs), is capable of detecting objects in
a scale and rotation invariant manner, along with the shift invariance feature,
by incorporating polar mellin transform (PMT). We also illustrate a key
limitation of the ideas presented in previous papers on performing PMT and
present a solution to circumvent this limitation by cutting out a small circle
at the center of the Fourier Transform which precedes PMT. Furthermore, we show
how to carry out shift, rotation and scale invariant detection of multiple
matching objects simultaneously, a process previously thought to be
incompatible with PMT based correlators. We present results of numerical
simulations to validate the concepts.


title: Systematic and non-systematic mortality risk in pension portfolios

abstract:
  We study the effects of non-systematic and systematic mortality risks on the
required initial capital in a pension plan, in the presence of financial risks.
We discover that for a pension plan with few members the impact of pooling on
the required capital per person is strong, but non-systematic risk diminishes
rapidly as the number of members increases. Systematic mortality risk, on the
other hand, is a significant source of risk is a pension portfolio.


title: Detecting chaos in a complex system

abstract:
  The sequences, given by a 7D map have been analysed by means of the methods,
widely used to detect chaos in the real world in order to test their
sensitivity to chaotic features of a non-linear system determined by
comparatively high number of parameters. The same diagnostic approaches have
been applied to the 3D Lorenz map for comparison. The results show that for
some of the sequences yielded from the 7D map, the adopted methods were not
able to give as straightforward answer to the question if the system is chaotic
as in the 3D case. Since the sequences, subject of the analysis, were not
contaminated by noise and were sufficiently long, it could be assumed that such
difficulties have arisen likely due to specific internal features of the more
complex system. It was found also that an increase from 0.01 to 0.5 of the
sampling step determining the sequences obtained from the 7D map, masks the
chaos in some of them.


title:
A comparison of slip, disjoining pressure, and interface formation
  models for contact line motion through asymptotic analysis of thin
  two-dimensional droplet spreading

abstract:
  The motion of a contact line is examined, and comparisons drawn, for a
variety of models proposed in the literature. Pressure and stress behaviours at
the contact line are examined in the prototype system of quasistatic spreading
of a thin two-dimensional droplet on a planar substrate. The models analysed
include three disjoining pressure models based on van der Waals interactions, a
model introduced for polar fluids, and a liquid-gas diffuse-interface model;
Navier-slip and two non-linear slip models are investigated, with three
microscopic contact angle boundary conditions imposed (two of these contact
angle conditions having a contact line velocity dependence); and the interface
formation model is also considered. In certain parameter regimes it is shown
that all of the models predict the same quasistatic droplet spreading
behaviour.


title:
Planetary nebulae after common-envelope phases initiated by low-mass red
  giants

abstract:
  It is likely that at least some planetary nebulae are composed of matter
which was ejected from a binary star system during common-envelope (CE)
evolution. For these planetary nebulae the ionizing component is the hot and
luminous remnant of a giant which had its envelope ejected by a companion in
the process of spiralling-in to its current short-period orbit. A large
fraction of CE phases which end with ejection of the envelope are thought to be
initiated by low-mass red giants, giants with inert, degenerate helium cores.
We discuss the possible end-of-CE structures of such stars and their subsequent
evolution to investigate for which structures planetary nebulae are formed. We
assume that a planetary nebula forms if the remnant reaches an effective
temperature greater than 30 kK within 10^4 yr of ejecting its envelope. We
assume that the composition profile is unchanged during the CE phase so that
possible remnant structures are parametrized by the end-of-CE core mass,
envelope mass and entropy profile. We find that planetary nebulae are expected
in post-CE systems with core masses greater than about 0.3 solar masses if
remnants end the CE phase in thermal equilibrium. We show that whether the
remnant undergoes a pre-white dwarf plateau phase depends on the prescribed
end-of-CE envelope mass. Thus, observing a young post-CE system would constrain
the end-of CE envelope mass and post-CE evolution.