title: Bounded Approximate Symbolic Dynamic Programming for Hybrid MDPs

abstract:
  Recent advances in symbolic dynamic programming (SDP) combined with the
extended algebraic decision diagram (XADD) data structure have provided exact
solutions for mixed discrete and continuous (hybrid) MDPs with piecewise linear
dynamics and continuous actions. Since XADD-based exact solutions may grow
intractably large for many problems, we propose a bounded error compression
technique for XADDs that involves the solution of a constrained bilinear saddle
point problem. Fortuitously, we show that given the special structure of this
problem, it can be expressed as a bilevel linear programming problem and solved
to optimality in finite time via constraint generation, despite having an
infinite set of constraints. This solution permits the use of efficient linear
program solvers for XADD compression and enables a novel class of bounded
approximate SDP algorithms for hybrid MDPs that empirically offers
order-of-magnitude speedups over the exact solution in exchange for a small
approximation error.


title: On MAP Inference by MWSS on Perfect Graphs

abstract:
  Finding the most likely (MAP) configuration of a Markov random field (MRF) is
NP-hard in general. A promising, recent technique is to reduce the problem to
finding a maximum weight stable set (MWSS) on a derived weighted graph, which
if perfect, allows inference in polynomial time. We derive new results for this
approach, including a general decomposition theorem for MRFs of any order and
number of labels, extensions of results for binary pairwise models with
submodular cost functions to higher order, and an exact characterization of
which binary pairwise MRFs can be efficiently solved with this method. This
defines the power of the approach on this class of models, improves our toolbox
and expands the range of tractable models.


title:
Charge-density-wave formation in the Edwards fermion-boson model at
  one-third band filling

abstract:
  We examine the ground-state properties of the one-dimensional Edwards
spinless fermion transport model by means of large-scale density-matrix
renormalization-group calculations. Determining the single-particle gap and the
Tomonaga-Luttinger liquid parameter ($K_\rho$) at zero temperature, we prove
the existence of a metal-to-insulator quantum phase transition at one-third
band filling. The insulator---established by strong correlation in the
background medium---typifies a charge density wave (CDW) that is commensurate
with the band filling. $K_\rho=2/9$ is very small at the quantum critical
point, and becomes $K_\rho^{\rm CDW}=1/9$ in the infinitesimally doped
three-period CDW, as predicted by the bosonization approach.


title: Integrating Document Clustering and Topic Modeling

abstract:
  Document clustering and topic modeling are two closely related tasks which
can mutually benefit each other. Topic modeling can project documents into a
topic space which facilitates effective document clustering. Cluster labels
discovered by document clustering can be incorporated into topic models to
extract local topics specific to each cluster and global topics shared by all
clusters. In this paper, we propose a multi-grain clustering topic model
(MGCTM) which integrates document clustering and topic modeling into a unified
framework and jointly performs the two tasks to achieve the overall best
performance. Our model tightly couples two components: a mixture component used
for discovering latent groups in document collection and a topic model
component used for mining multi-grain topics including local topics specific to
each cluster and global topics shared across clusters.We employ variational
inference to approximate the posterior of hidden variables and learn model
parameters. Experiments on two datasets demonstrate the effectiveness of our
model.


title: Active Learning with Expert Advice

abstract:
  Conventional learning with expert advice methods assumes a learner is always
receiving the outcome (e.g., class labels) of every incoming training instance
at the end of each trial. In real applications, acquiring the outcome from
oracle can be costly or time consuming. In this paper, we address a new problem
of active learning with expert advice, where the outcome of an instance is
disclosed only when it is requested by the online learner. Our goal is to learn
an accurate prediction model by asking the oracle the number of questions as
small as possible. To address this challenge, we propose a framework of active
forecasters for online active learning with expert advice, which attempts to
extend two regular forecasters, i.e., Exponentially Weighted Average Forecaster
and Greedy Forecaster, to tackle the task of active learning with expert
advice. We prove that the proposed algorithms satisfy the Hannan consistency
under some proper assumptions, and validate the efficacy of our technique by an
extensive set of experiments.


title:
Bennett-type Generalization Bounds: Large-deviation Case and Faster Rate
  of Convergence

abstract:
  In this paper, we present the Bennett-type generalization bounds of the
learning process for i.i.d. samples, and then show that the generalization
bounds have a faster rate of convergence than the traditional results. In
particular, we first develop two types of Bennett-type deviation inequality for
the i.i.d. learning process: one provides the generalization bounds based on
the uniform entropy number; the other leads to the bounds based on the
Rademacher complexity. We then adopt a new method to obtain the alternative
expressions of the Bennett-type generalization bounds, which imply that the
bounds have a faster rate o(N^{-1/2}) of convergence than the traditional
results O(N^{-1/2}). Additionally, we find that the rate of the bounds will
become faster in the large-deviation case, which refers to a situation where
the empirical risk is far away from (at least not close to) the expected risk.
Finally, we analyze the asymptotical convergence of the learning process and
compare our analysis with the existing results.


title: Virtual photon-photon scattering

abstract:
  Based on analyticity, unitarity, and Lorentz invariance the contribution from
hadronic vacuum polarization to the anomalous magnetic moment of the muon is
directly related to the cross section of e^+e^- --> hadrons. We review the main
difficulties that impede such an approach for light-by-light scattering and
identify the required ingredients from experiment. Amongst those, the most
critical one is the scattering of two virtual photons into meson pairs. We
analyze the analytic structure of the process gamma^* gamma^* --> pi pi and
show that the usual Muskhelishvili-Omnes representation can be amended in such
a way as to remain valid even in the presence of anomalous thresholds.


title: Maxwell group and HS field theory

abstract:
  We consider the master fields for HS multiplets defined on 10-dimensional
tensorial extension \tilde{\cal M} of D=4 space-time described as a coset
\tilde{\cal M}={\cal M}/Sl(2;C) of 16-parameter Maxwell group {\cal M}. The
tensorial coordinates provide a geometrization of the coupling to constant
uniform EM fields. We describe the spinorial model in extended space-time
\tilde{\cal M} and by its first quantization we obtain new infinite HS-Maxwell
multiplets with their massless components coupled to each other through
constant EM background. We conclude our report by observing that
three-dimensional spinorial model with a pair of spinors should provide after
quantization D=3 massive HS-Maxwell multiplets.


title:
String loops in the field of braneworld spherically symmetric black
  holes and naked sigularities

abstract:
  We study motion of current-carrying string loops in the field of braneworld
spherically symmetric black holes and naked singularities. The spacetime is
described by the RN geometry with tidal charge b reflecting the non-local tidal
effects coming from the external dimension; both positive and negative values
of the spacetime parameter b are considered. We restrict attention to the
axisymmetric motion of string loops when the motion can be fully governed by an
appropriately defined effective potential related to the energy and angular
momentum of the string loops. In dependence on these two constants of the
motion, the string loops can be captured, trapped, or can escape to infinity.
In close vicinity of stable equilibrium points at the centre of trapped states
the motion is regular. We describe how it is transformed to chaotic motion with
growing energy of the string loop. In the field of naked singularities the
trapped states located off the equatorial plane of the system exist and
trajectories unable to cross the equatorial plane occur, contrary to the
trajectories in the field of black holes where crossing the equatorial plane is
always admitted. We concentrate our attention to the so called transmutation
effect when the string loops are accelerated in the deep gravitational field
near the black hole or naked singularity by transforming the oscillatory energy
to the energy of the transitional motion. We demonstrate that the influence of
the tidal charge can be substantial especially in the naked singularity
spacetimes with b>1 where the acceleration to ultrarelativistic velocities with
Lorentz factor \gamma{} ~ 100 can be reached, being more than one order higher
in comparison with those obtained in the black hole spacetimes.


title: Diffusion asymptotics for linear transport with low regularity

abstract:
  We provide an asymptotic analysis of linear transport problems in the
diffusion limit under minimal regularity assumptions on the domain, the
coefficients, and the data. The weak form of the limit equation is derived and
the convergence of the solution in the $L^2$ norm is established without
artificial regularity requirements. This is important to be able to deal with
problems involving realistic geometries and heterogeneous media. In a second
step we prove the usual $O(\varepsilon)$ convergence rates under very mild
additional assumptions. The generalization of the results to convergence in
$L^p$ with $p \ne 2$ and some limitations are discussed.


title:
Quantification of errors in large-eddy simulations of a
  spatially-evolving mixing layer

abstract:
  A stochastic approach based on generalized Polynomial Chaos (gPC) is used to
quantify the error in Large-Eddy Simulation (LES) of a spatially-evolving
mixing layer flow and its sensitivity to different simulation parameters, viz.
the grid stretching in the streamwise and lateral directions and the subgrid
scale model constant ($C_S$). The error is evaluated with respect to the
results of a highly resolved LES (HRLES) and for different quantities of
interest, namely the mean streamwise velocity, the momentum thickness and the
shear stress. A typical feature of the considered spatially evolving flow is
the progressive transition from a laminar regime, highly dependent on the inlet
conditions, to a fully-developed turbulent one. Therefore the computational
domain is divided in two different zones (\textit{inlet dependent} and
\textit{fully turbulent}) and the gPC error analysis is carried out for these
two zones separately. An optimization of the parameters is also carried out for
both these zones. For all the considered quantities, the results point out that
the error is mainly governed by the value of the $C_S$ constant. At the end of
the inlet-dependent zone a strong coupling between the normal stretching ratio
and the $C_S$ value is observed. The error sensitivity to the parameter values
is significantly larger in the inlet-dependent upstream region; however, low
error values can be obtained in this region for all the considered physical
quantities by an ad-hoc tuning of the parameters. Conversely, in the turbulent
regime the error is globally lower and less sensitive to the parameter
variations, but it is more difficult to find a set of parameter values leading
to optimal results for all the analyzed physical quantities.


title: Q-functions and boundary triplets of nonnegative operators

abstract:
  Operator-valued $Q$-functions for special pairs of nonnegative selfadjoint
extensions of nonnegative not necessarily densely defined operators are defined
and their analytical properties are studied. It is shown that the Kre\u\i
n-Ovcharenko statement announced in \cite{KrO2} is valid only for $Q$-functions
of densely defined symmetric operators with finite deficiency indices. A
general class of boundary triplets for a densely defined nonnegative operator
is constructed such that the corresponding Weyl functions are of Kre\u\i
n-Ovcharenko type.


title:
Predicate Logic as a Modeling Language: Modeling and Solving some
  Machine Learning and Data Mining Problems with IDP3

abstract:
  This paper provides a gentle introduction to problem solving with the IDP3
system. The core of IDP3 is a finite model generator that supports first order
logic enriched with types, inductive definitions, aggregates and partial
functions. It offers its users a modeling language that is a slight extension
of predicate logic and allows them to solve a wide range of search problems.
Apart from a small introductory example, applications are selected from
problems that arose within machine learning and data mining research. These
research areas have recently shown a strong interest in declarative modeling
and constraint solving as opposed to algorithmic approaches. The paper
illustrates that the IDP3 system can be a valuable tool for researchers with
such an interest.
  The first problem is in the domain of stemmatology, a domain of philology
concerned with the relationship between surviving variant versions of text. The
second problem is about a somewhat related problem within biology where
phylogenetic trees are used to represent the evolution of species. The third
and final problem concerns the classical problem of learning a minimal
automaton consistent with a given set of strings. For this last problem, we
show that the performance of our solution comes very close to that of a
state-of-the art solution. For each of these applications, we analyze the
problem, illustrate the development of a logic-based model and explore how
alternatives can affect the performance.


title: High resolution simulations of the head-on collision of white dwarfs

abstract:
  The direct impact of white dwarfs has been suggested as a plausible channel
for type Ia supernovae. In spite of their (a priori) rareness, in highly
populated globular clusters and in galactic centers, where the amount of white
dwarfs is considerable, the rate of violent collisions between two of them
might be non-negligible. Even more, there are indications that binary white
dwarf systems orbited by a third stellar-mass body have an important chance to
induce a clean head-on collision. Therefore, this scenario represents a source
of contamination for the supernova light-curves sample that it is used as
standard candles in cosmology, and it deserves further investigation. Some
groups have conducted numerical simulations of this scenario, but their results
show several differences. In this paper we address some of the possible sources
of these differences, presenting the results of high resolution hydrodynamical
simulations jointly with a detailed nuclear post-processing of the nuclear
abundances, to check the viability of white dwarf collisions to produce
significant amounts of 56Ni. To that purpose, we use a 2D-axial symmetric
smoothed particle hydrodynamic code to obtain a resolution considerably higher
than in previous studies. In this work, we also study how the initial mass and
nuclear composition affect the results. The gravitational wave emission is also
calculated, as this is a unique signature of this kind of events. All
calculated models produce a significant amount of 56Ni, ranging from 0.1 Msun
to 1.1 Msun, compatible not only with normal-Branch type Ia supernova but also
with the subluminous and super-Chandrasekhar subset. Nevertheless, the
distribution mass-function of white dwarfs favors collisions among 0.6-0.7 Msun
objects, leading to subluminous events.


title:
Upgrade of the POLDI diffractometer with a ZnS(Ag)/6LiF scintillation
  detector read out with WLS fibers coupled to SiPMs

abstract:
  A thermal neutron detector based on ZnS(Ag)/6LiF scintillator,
wavelength-shifting fibers (WLS) and silicon photomultipliers (SiPM) is under
development at the Paul Scherrer Institute (PSI) for upgrading the POLDI
instrument, a pulse-overlap diffractometer. The design of the detector is
outlined, and the measurements performed on a single channel prototype are
presented. An innovative signal processing system based on a photon counting
approach is under development. Its principle of operation is described and its
performances are evaluated on the basis of a Monte Carlo simulation.


title:
Enhancement models of momentum densities of annihilating
  electron-positron pairs: the many-body picture of natural geminals

abstract:
  The correlated motion of a positron surrounded by electrons is a fundamental
many-body problem. We approach this by modeling the momentum density of
annihilating electron-positron pairs using the framework of reduced density
matrices, natural orbitals and natural geminals (electron-positron pair wave
functions) of the quantum theory of many-particle systems. We find that an
expression based on the natural geminals provides an exact, unique and compact
expression for the momentum density. The natural geminals can be used to define
and determine enhancement factors for enhancement models going beyond the
independent-particle model for a better understanding of results of positron
annihilation experiments.


title:
The real radiation antenna functions for $S\rightarrow Q\bar{Q}gg$ at
  NNLO QCD

abstract:
  We analyze, in the antenna subtraction framework, the real radiation antenna
functions for processes involving the production of a pair of heavy quarks and
two gluons by an uncolored initial state at NNLO QCD. We provide explicit
expressions for these functions and discuss their infrared singular behaviour.
Our main results are the corresponding integrated antenna functions which are
computed analytically. They are expressed in terms of harmonic polylogarithms.


title:
Search for a doubly-charged boson in four lepton final states in type II
  seesaw

abstract:
  CMS and ATLAS have searched for a doubly-charged boson $H^{\pm\pm}$ which may
arise from type II seesaw in the 7 TeV run at the LHC by considering pair or
associated production of doubly-charged bosons under the assumption of
degenerate triplet scalars. In this work, we consider non-degenerate triplet
components with the mass gap $\Delta M \sim 1 - 40$ GeV which leads to enhanced
pair-production cross-sections of $H^{\pm\pm}$ added by the gauge decays of the
heavier neutral and singly-charged bosons. We reevaluate the constraints in the
$\Delta M-M_{H^{++}}$ plane depending on the triplet vacuum expectation value
$v_\Delta$ in the type II seesaw model which are much more stringent than the
current search limits. We further study the possibility of observing same-sign
tetra-lepton signals in the allowed parameter space which can be probed in the
future runs of the LHC.


title: Non-adiabatic charge state transitions in singlet-triplet qubits

abstract:
  In double quantum dot singlet-triplet qubits, the exchange interaction is
used in both quantum gate operation and the measurement of the state of the
qubit. The exchange can be controlled electronically by applying gate voltage
pulses. We simulate the exchange induced charge state transitions in one and
two singlet-triplet qubit systems using the exact diagonalization method. We
find that fast detuning pulses may result in leakage between different singlet
charge states. The leakage could cause measurement errors and hinder quantum
gate operation for example in the case of the two-qubit Coulomb gate.


title:
Comment on "Sudden change in quantum discord accompanying the transition
  from bound to free entanglement"

abstract:
  In a recent article [http://dx.doi.org/10.1103/PhysRevA.87.022340, Phys. Rev.
A 87, 022340 (2013)], Yan et al have studied geometric discord for a well known
class of bound entangled states. Based on their calculation, they claim "It is
found that there exists a nondynamic sudden change in quantum discord" for
these states. In this Comment, we criticize their work by pointing out that
what has been calculated is actually a bound, and not the exact value of
discord. Since, generally, it is not possible to infer the exact value (or
property) of a quantity just from its bound, we can not conclude about (exact)
discord and its change. Thus, the above-mentioned conclusion can not be drawn
from the calculations of the paper.


title: Density-temperature scaling of the fragility in a model glass-former

abstract:
  Dynamical quantities such as the diffusion coefficient and relaxation times
for some glass-formers may depend on density and temperature through a specific
combination, rather than independently, allowing the representation of data
over ranges of density and temperature as a function of a single scaling
variable. Such a scaling, referred to as density - temperature (DT) scaling, is
exact for liquids with inverse power law (IPL) interactions but has also been
found to be approximately valid in many non-IPL liquids. We have analyzed the
consequences of DT scaling on the density dependence of the fragility in a
model glass-former. We find the density dependence of kinetic fragility to be
weak, and show that it can be understood in terms of DT scaling and deviations
of DT scaling at low densities. We also show that the Adam-Gibbs relation
exhibits DT scaling and the scaling exponent computed from the density
dependence of the activation free energy in the Adam-Gibbs relation, is
consistent with the exponent values obtained by other means.


title: Comment on the Theory of the Stretching Experiments of RNA in Water

abstract:
  Is is argued that the stretching experiments done on RNA in water can be
described as a reversible process by Classical Thermodynamics.


title: Discovery of an extended X-ray jet in AP Librae

abstract:
  Chandra observations of the low-energy peaked BL Lac object AP Librae
revealed the clear discovery of a non-thermal X-ray jet. AP Lib is the first
low energy peaked BL Lac object with an extended non-thermal X-ray jet that
shows emission into the VHE range. The X-ray jet has an extension of ~15'' (~
14 kpc). The X-ray jet morphology is similar to the radio jet observed with VLA
at 1.36 GHz emerging in south-east direction and bends by 50 degrees at a
distance of 12'' towards north-east. The intensity profiles of the X-ray
emission are studied consistent with those found in the radio range. The
spectral analysis reveals that the X-ray spectra of the core and jet region are
both inverse Compton dominated. This adds to a still small sample of BL Lac
objects whose X-ray jets are IC dominated and thus more similar to the high
luminosity FRII sources than to the low luminosity FRI objects, which are
usually considered to be the parent population of the BL Lac objects.


title: Optimal number of terms in QED series

abstract:
  In 1952 Dyson put forward a simple and powerful argument indicating that the
perturbative expansions of QED are asymptotic. His argument can be related to
Chandrasekhar's limit on the mass of a star for stability against gravitational
collapse. Combining these two arguments we estimate the optimal number of terms
of the QED series to be 3.1(137)^{3/2}=5000.


title:
Consistency, breakdown robustness, and algorithms for robust improper
  maximum likelihood clustering

abstract:
  The robust improper maximum likelihood estimator (RIMLE) is a new method for
robust multivariate clustering finding approximately Gaussian clusters. It
maximizes a pseudo-likelihood defined by adding a component with improper
constant density for accommodating outliers to a Gaussian mixture. A special
case of the RIMLE is MLE for multivariate finite Gaussian mixture models. In
this paper we treat existence, consistency, and breakdown theory for the RIMLE
comprehensively. RIMLE's existence is proved under non-smooth covariance matrix
constraints. It is shown that these can be implemented via a computationally
feasible Expectation-Conditional Maximization algorithm.


title: Observational issues in loop quantum cosmology

abstract:
  Quantum gravity is sometimes considered as a kind of metaphysical
speculation. In this review, we show that, although still extremely difficult
to reach, observational signatures can in fact be expected. The early universe
is an invaluable laboratory to probe "Planck scale physics". Focusing on Loop
Quantum Gravity as one of the best candidate for a non-perturbative and
background-independant quantization of gravity, we detail some expected
features.


title:
Efficient Optimization of the Likelihood Function in Gaussian Process
  Modelling

abstract:
  Gaussian Process (GP) models are popular statistical surrogates used for
emulating computationally expensive computer simulators. The quality of a GP
model fit can be assessed by a goodness of fit measure based on optimized
likelihood. Finding the global maximum of the likelihood function for a GP
model is typically very challenging as the likelihood surface often has
multiple local optima, and an explicit expression for the gradient of the
likelihood function is typically unavailable. Previous methods for optimizing
the likelihood function (e.g. MacDonald et al. (2013)) have proven to be robust
and accurate, though relatively inefficient. We propose several likelihood
optimization techniques, including two modified multi-start local search
techniques, based on the method implemented by MacDonald et al. (2013), that
are equally as reliable, and significantly more efficient. A hybridization of
the global search algorithm Dividing Rectangles (DIRECT) with the local
optimization algorithm BFGS provides a comparable GP model quality for a
fraction of the computational cost, and is the preferred optimization technique
when computational resources are limited. We use several test functions and a
real application from an oil reservoir simulation to test and compare the
performance of the proposed methods with the one implemented by MacDonald et
al. (2013) in the R library GPfit. The proposed method is implemented in a
Matlab package, GPMfit.


title: The Paradox of Power Loss in a Lossless Infinite Transmission Line

abstract:
  We discuss here the famous paradox of a continuous power drainage from the
source at the input of an otherwise lossless infinite transmission line. The
solution of the paradox lies in the realization that in an open-circuit finite
transmission line/ladder network, there is an incident as well as a reflected
wave and the input impedence is determined by the superposition of both waves.
It is explicitly shown that the reactive input impedance of even a single
block, comprising say a simple LC circuit, is determined at all driving
frequencies from the superposition of incident and reflected waves, and that
the input impedance remains reactive in nature (i.e., an imaginary value) even
when additional blocks are added indefinitely. However in a ladder network or
transmission line, taken to be {\em infinite right from the beginning}, there
is no reflected wave (assuming the circuit to be ideal with no discontinuities
en route). Thus the source while continuously supplying power in the forward
direction, does not retrieve it from a reflected wave and unlike in the case of
a finite line, there is a net power loss. This apparently lost energy
ultimately appears in the electromagnetic fields in the reactive elements
(capacitances and inductances which to begin with had no such stored energy),
further down the line as the incident wave advances forward. It is also shown
that radiation plays absolutely no role in resolving this intriguing paradox.


title: Macro-element interpolation on tensor product meshes

abstract:
  A general theory for obtaining anisotropic interpolation error estimates for
macro-element interpolation is developed revealing general construction
principles. We apply this theory to interpolation operators on a macro type of
biquadratic $C^1$ finite elements on rectangle grids which can be viewed as a
rectangular version of the $C^1$ Powell-Sabin element. This theory also shows
how interpolation on the Bogner-Fox-Schmidt finite element space (or higher
order generalizations) can be analyzed in a unified framework. Moreover we
discuss a modification of Scott-Zhang type giving optimal error estimates under
the regularity required without imposing quasi uniformity on the family of
macro-element meshes used. We introduce and analyze an anisotropic
macro-element interpolation operator, which is the tensor product of
one-dimensional $C^1-P_2$ macro interpolation and $P_2$ Lagrange interpolation.
These results are used to approximate the solution of a singularly perturbed
reaction-diffusion problem on a Shishkin mesh that features highly anisotropic
elements. Hereby we obtain an approximation whose normal derivative is
continuous along certain edges of the mesh, enabling a more sophisticated
analysis of a continuous interior penalty method in another paper.


title:
A Numerical Model of Philippine Population Growth: Child Policy,
  Quantitative Insights and Challenges

abstract:
  In this study, we forecast the population of the Philippines using a discrete
age-structured compartmental model. We estimated the future population
structure of the Philippines if the government imposes an n-child policy on top
of the declining current birth and death rate trend of the country.


title: Current heating induced spin Seebeck effect

abstract:
  A new measurement technique for the spin Seebeck effect is presented, wherein
the normal metal layer used for its detection is exploited simultaneously as a
resistive heater and thermometer. We show how the various contributions to the
measured total signal can be disentangled, allowing to extract the voltage
signal solely caused by the spin Seebeck effect. To this end we performed
measurements as a function of the external magnetic field strength and its
orientation. We find that the effect scales linearly with the induced rise in
temperature, as expected for the spin Seebeck effect.


title: Matrix Gegenbauer Polynomials: the $2\times 2$ Fundamental Cases

abstract:
  In this paper, we exhibit explicitly a sequence of $2\times2$ matrix valued
orthogonal polynomials with respect to a weight $W_{p,n}$, for any pair of real
numbers $p$ and $n$ such that $0<p<n$.
  The entries of these polynomiales are expressed in terms of the Gegenbauer
polynomials $C_k^\lambda$. Also the corresponding three-term recursion
relations are given and we make some studies of the algebra of differential
operators associated with the weight $W_{p,n}$.


title:
The algebra of conditional sets and the concepts of conditional topology
  and compactness

abstract:
  The concepts of a conditional set, a conditional inclusion relation and a
conditional Cartesian product are introduced. The resulting conditional set
theory is sufficiently rich in order to construct a conditional topology, a
conditional real and functional analysis indicating the possibility of a
mathematical discourse based on conditional sets. It is proved that the
conditional power set is a complete Boolean algebra, and a conditional version
of the axiom of choice, the ultrafilter lemma, Tychonoff's theorem, the
Borel-Lebesgue theorem, the Hahn-Banach theorem, the Banach-Alaoglu theorem and
the Krein-\v{S}mulian theorem are shown.


title: On $p$-gonal fields of definition

abstract:
  Let $S$ be a closed Riemann surface of genus $g \geq 2$ and $\varphi$ be a
conformal automorphism of $S$, of prime order $p$ such that $S/\langle \varphi
\rangle$ has genus zero. Let ${\mathbb K} \leq {\mathbb C}$ be a field of
definition of $S$, that is, there is an irreducible curve $C$, defined over
${\mathbb K}$, whose Riemann surface structure is biholomorphic to $S$. We
provide a simple argument for the existence of a field extension ${\mathbb F}$
of ${\mathbb K}$, of degree at most $2(p-1)$, for which $S$ is definable by a
curve of the form $y^{p}=F(x) \in {\mathbb F}[x]$, in which case $\varphi$
corresponds to $(x,y) \mapsto (x,e^{2 \pi i/p} y)$. If, moreover, $\varphi$ is
also definable over ${\mathbb K}$, then ${\mathbb F}$ can be chosen to be a
quadratic extension of ${\mathbb K}$. For $p=2$, that is when $S$ is
hyperelliptic and $\varphi$ is its hyperelliptic involution, this fact is due
to Mestre (for even genus) and Huggins and Lercier-Ritzenthaler-Sijslingit in
the case that ${\rm Aut}(S)/\varphi\rangle$ is non-trivial.


title:
A Search for non-Newtonian force in a precision measurement of the
  scattering of slow neutrons in Xenon gas

abstract:
  An experimental search for non-newtonian, gravity-like force in a precision
measurement of the scattering of slow neutrons in Xenon gas is proposed. A
preliminary experiment with small statistics of 25 hours irradiation time was
performed and the observed scattering distribution is consistent with the
expectation with no additional forces. A 95% CL limit on the coupling strength
for a hypothetical force of 1 nm interaction range was evaluated to be
2*10^-15. The expected sensitivity for a planned high statistics runs is
discussed.


title:
Hellinger Distance and Bayesian Non-Parametrics: Hierarchical Models for
  Robust and Efficient Bayesian Inference

abstract:
  This paper introduces a hierarchical framework to incorporate Hellinger
distance methods into Bayesian analysis. We propose to modify a prior over
non-parametric densities with the exponential of twice the Hellinger distance
between a candidate and a parametric density. By incorporating a prior over the
parameters of the second density, we arrive at a hierarchical model in which a
non-parametric model is placed between parameters and the data. The parameters
of the family can then be estimated as hyperparameters in the model. In
frequentist estimation, minimizing the Hellinger distance between a kernel
density estimate and a parametric family has been shown to produce estimators
that are both robust to outliers and statistically efficient when the
parametric model is correct. In this paper, we demonstrate that the same
results are applicable when a non-parametric Bayes density estimate replaces
the kernel density estimate. We then demonstrate that robustness and efficiency
also hold for the proposed hierarchical model. The finite-sample behavior of
the resulting estimates is investigated by simulation and on real world data.


title: $ttH$ Anomalous Coupling in Double Higgs Production

abstract:
  We study the effects of top-Higgs anomalous coupling in the production of a
pair of Higgs boson via gluon fusion at the Large Hadron Collider (LHC). The
introduction of anomalous $ttH$ coupling can alter the hadronic double Higgs
boson cross section and can lead to characteristic changes in certain kinematic
distributions. We perform a global analysis based on available LHC data on the
Higgs to constrain the parameters of $ttH$ anomalous coupling. Possible overlap
of the predictions due to anomalous $ttH$ coupling with those due to anomalous
trilinear Higgs coupling is also studied. We briefly discuss the effect of the
anomalous $ttH$ coupling on the $HZ$ production via gluon fusion which is one
of the main backgrounds in the $HH \to \gamma\gamma b {\bar b}$ channel.


title:
A Collaborative Filtering Based Approach for Recommending Elective
  Courses

abstract:
  In management education programmes today, students face a difficult time in
choosing electives as the number of electives available are many. As the range
and diversity of different elective courses available for selection have
increased, course recommendation systems that help students in making choices
about courses have become more relevant. In this paper we extend the concept of
collaborative filtering approach to develop a course recommendation system. The
proposed approach provides student an accurate prediction of the grade they may
get if they choose a particular course, which will be helpful when they decide
on selecting elective courses, as grade is an important parameter for a student
while deciding on an elective course. We experimentally evaluate the
collaborative filtering approach on a real life data set and show that the
proposed system is effective in terms of accuracy.


title:
The Farrell-Jones conjecture for fundamental groups of graphs of abelian
  groups

abstract:
  We show that the Farrell-Jones Conjecture holds for fundamental groups of
graphs of groups with abelian vertex groups. As a special case, this shows that
the conjecture holds for generalized Baumslag-Solitar groups.


title: A note about combinatorial sequences and Incomplete Gamma function

abstract:
  In this short note we present a set of interesting and useful properties of a
one-parameter family of sequences including factorial and subfactorial, and
their relations to the Gamma function and the incomplete Gamma function.


title: Moore-Penrose inverse and doubly commuting elements in $C^*$-algebras

abstract:
  In this work it is proved that the Moore-Penrose inverse of the product of
$n$-doubly commuting regular $C^*$-algebra elements obeys the so-called reverse
order law. Conversely, conditions regarding the reverse order law of the
Moore-Penrose inverse are given in order to characterize when $n$-regular
elements doubly commute. Furthermore, applications of the main results of this
article to normal $C^*$-algebra elements, to Hilbert space operators and to
Calkin algebras will be considered.


title: Long wavelength instability of coherent structures in plane Couette flow

abstract:
  We study the stability of coherent structures in plane Couette flow against
long-wavelength perturbations in wide domains that cover several pairs of
coherent structures. For one and two pairs of vortices, the states retain the
stability properties of the small domains, but for three pairs new unstable
modes are found. They are shown to be connected to bifurcations that break the
translational symmetry and drive the coherent structures from the spanwise
extended state to a modulated one that is a precursor to spanwise localized
states. Tracking the stability of the orbits as functions of the spanwise wave
length reveals a rich variety of additional bifurcations.


title: Dynamical symmetries of the Kepler problem

abstract:
  This work originates from a first year undergraduate research project on
hidden symmetries of the dynamics for classical Hamiltonian systems, under the
program 'Jovens talentos para a Ciencia' of Brazilian funding agency Capes. For
pedagogical reasons the main subject chosen was Kepler's problem of motion
under a central potential, since it is a completely solved system. It is well
known that for this problem the group of dynamical symmetries is strictly
larger than the isometry group O(3), the extra symmetries corresponding to
hidden symmetries of the dynamics. By taking the point of view of examining the
group action of the dynamical symmetries on the allowed trajectories, it is
possible to teach in the same project basic elements of as many important
subjects in physics as: Hamiltonian formalism, hidden symmetries, integrable
systems, group theory, and the use of manifolds.


title: Chemical concrete machine

abstract:
  The chemical concrete machine is a graph rewriting system which uses only
local moves (rewrites), seen as chemical reactions involving molecules which
are graphs made up by 4 trivalent nodes. It is Turing complete, therefore it
might be used as a model of computation in algorithmic chemistry.


title: Spectral synthesis in de Branges spaces

abstract:
  We solve completely the spectral synthesis problem for reproducing kernels in
the de Branges spaces $\mathcal{H}(E)$. Namely, we describe the de Branges
spaces $\mathcal{H}(E)$ such that all $M$-bases of reproducing kernels (i.e.,
complete and minimal systems $\{k_\lambda\}_{\lambda\in\Lambda}$ with complete
biorthogonal $\{g_\lambda\}_{\lambda\in\Lambda}$) are strong $M$-bases (i.e.,
every mixed system $\{k_\lambda\}_{\lambda\in\Lambda\setminus\tilde \Lambda}
\cup\{g_\lambda\}_{\lambda\in \tilde \Lambda}$ is also complete). Surprisingly
this property takes place only for two essentially different classes of de
Branges spaces: spaces with finite spectral measure and spaces which are
isomorphic to Fock-type spaces of entire functions. The first class goes back
to de Branges himself, the second class appeared in a recent work of A.
Borichev and Yu. Lyubarskii. Moreover, we are able to give a complete
characterisation of this second class in terms of the spectral data for
$\mathcal{H}(E)$. In addition, we obtain some results about possible
codimension of mixed systems for a fixed de Branges space $\mathcal{H}(E)$, and
prove that any minimal system of reproducing kernels in $\mathcal{H}(E)$ is
contained in an exact system of reproducing kernels.


title: MHD Simulations of Global Accretion Disks with Vertical Magnetic Fields

abstract:
  (Abridged) We report results of three dimensional MHD simulations of global
accretion disks threaded with weak vertical magnetic fields. We perform the
simulations in the spherical coordinates with different temperature profiles
and accordingly different rotation profiles. In the cases with a spatially
constant temperature, because the rotation frequency is vertically constant in
the equilibrium condition, general properties of the turbulence are
quantitatively similar to those obtained in local shearing box simulations. On
the other hand, in the cases with a radially variable temperature profile, the
vertical differential rotation, which is inevitable in the equilibrium
condition, winds up the magnetic field lines, in addition to the usual radial
differential rotation. As a result, the coherent wound magnetic fields
contribute to the Maxwell stress in the surface regions. We obtain
nondimensional density and velocity fluctuations ~0.1-0.2 at the midplane. The
azimuthal power spectra of the magnetic fields show shallow slopes, ~m^0-
m^{-1}, than those of velocity and density. We observe intermittent and
structured disk winds driven by the Poynting flux associated with the MHD
turbulence. The Poynting flux originating from magnetic tension is injected
from the regions above a scale height towards both the midplane and the
surfaces. Related to this, sound waves are directed to the midplane from the
surface regions. The mass accretion mainly occurs near the surfaces and the gas
near the midplane slowly moves outward, which causes large-scale meridional
circulations. The vertical magnetic fields are also dragged inward in the
surface regions, while they stochastically move outward and inward around the
midplane. We also discuss an observational implication of induced spiral
structure in the simulated turbulent disks to protoplanetary disks.


title:
On graded decomposition numbers for cyclotomic Hecke algebras in quantum
  characteristic 2

abstract:
  Brundan and Kleshchev introduced graded decomposition numbers for
representations of cyclotomic Hecke algebras of type $A$, which include group
algebras of symmetric groups. Graded decomposition numbers are certain Laurent
polynomials, whose values at 1 are the usual decomposition numbers. We show
that in quantum characteristic 2 every such polynomial has non-zero
coefficients either only in odd or only in even degrees. As a consequence, we
find the first examples of graded decomposition numbers of symmetric groups
with non-zero coefficients in some negative degrees.


title: Carbon nanotubes as heat dissipaters in microelectronics

abstract:
  We review our recent modelling work of carbon nanotubes as potential
candidates for heat dissipation in microelectronics cooling. In the first part,
we analyze the impact of nanotube defects on their thermal transport
properties. In the second part, we investigate the loss of thermal properties
of nanotubes in presence of an interface with various substances, including air
and water. Comparison with previous works is established whenever is possible.


title:
Accurate Profiling of Microbial Communities from Massively Parallel
  Sequencing using Convex Optimization

abstract:
  We describe the Microbial Community Reconstruction ({\bf MCR}) Problem, which
is fundamental for microbiome analysis. In this problem, the goal is to
reconstruct the identity and frequency of species comprising a microbial
community, using short sequence reads from Massively Parallel Sequencing (MPS)
data obtained for specified genomic regions. We formulate the problem
mathematically as a convex optimization problem and provide sufficient
conditions for identifiability, namely the ability to reconstruct species
identity and frequency correctly when the data size (number of reads) grows to
infinity. We discuss different metrics for assessing the quality of the
reconstructed solution, including a novel phylogenetically-aware metric based
on the Mahalanobis distance, and give upper-bounds on the reconstruction error
for a finite number of reads under different metrics. We propose a scalable
divide-and-conquer algorithm for the problem using convex optimization, which
enables us to handle large problems (with $\sim10^6$ species). We show using
numerical simulations that for realistic scenarios, where the microbial
communities are sparse, our algorithm gives solutions with high accuracy, both
in terms of obtaining accurate frequency, and in terms of species phylogenetic
resolution.


title:
Observation of a peaking structure in the J/psi phi mass spectrum from
  B(+/-) to J/psi phi K(+/-) decays

abstract:
  A peaking structure in the J/psi phi mass spectrum near threshold is observed
in B(+/-) to J/psi phi K(+/-) decays, produced in pp collisions at sqrt(s) = 7
TeV collected with the CMS detector at the LHC. The data sample, selected on
the basis of the dimuon decay mode of the J/psi, corresponds to an integrated
luminosity of 5.2 inverse femtobarns. Fitting the structure to an S-wave
relativistic Breit-Wigner lineshape above a three-body phase-space nonresonant
component gives a signal statistical significance exceeding five standard
deviations. The fitted mass and width values are m = 4148.0 +- 2.4 (stat.) +-
6.3 (syst.) MeV and Gamma = 28 +15 -11 (stat.) +- 19 (syst.) MeV, respectively.
Evidence for an additional peaking structure at higher J/psi phi mass is also
reported.


title:
A low-redshift low luminosity QSO sample: Comparison with NUGA galaxies
  and PG QSOs and first interferometric images of three sample members

abstract:
  The low luminosity QSO (LLQSO) sample consists of type 1 active galactic
nuclei (AGN) up to a redshift of z=0.06 in the Hamburg/ESO QSO survey. Its
purpose is to study how the brightest AGN in the nearby universe evolve with
respect to AGN activity and host properties as a function of redshift. We show
that our sample lies well between the NUclei of GAlaxies (NUGA) sample and the
Palomar Green (PG) QSO sample in terms of redshift, gas masses and luminosities
and seems to connect them. The continuous growth in mass, luminosity and,
linked to this, the AGN activity over the samples has either a statistical
reason or is indicative of an evolutionary link between the different
populations and might be related to cosmic downsizing. In addition, we present
first results of our observations of three galaxies from our sample with the
Submillimeter Array (SMA).


title: Two-body and Three-body Contacts for Identical Bosons near Unitarity

abstract:
  In a recent experiment with ultracold trapped Rb-85 atoms, Makotyn et al.
have studied a quantum-degenerate Bose gas in the unitary limit where its
scattering length is infinitely large. We show that the observed momentum
distributions are compatible with a universal relation that expresses the
high-momentum tail in terms of the 2-body and the 3-body contacts. We determine
the 2- and 3-body contact densities for the unitary Bose gas with number
density n to be approximately 20n^{4/3} and 2n^{5/3}, respectively. We also
show that the observed atom loss rate is compatible with that from 3-atom
inelastic collisions, which gives a contribution proportional to the 3-body
contact, but the loss rate is not compatible with that from 2-atom inelastic
collisions, which gives a contribution proportional to the 2-body contact. We
point out that the contacts could be measured independently by using the virial
theorem near and at unitarity.


title: Fifty years of the CERN Proton Synchrotron : Volume 2

abstract:
  This report sums up in two volumes the first 50 years of operation of the
CERN Proton Synchrotron. After an introduction on the genesis of the machine,
and a description of its magnet and powering systems, the first volume focuses
on some of the many innovations in accelerator physics and instrumentation that
it has pioneered, such as transition crossing, RF gymnastics, extractions,
phase space tomography, or transverse emittance measurement by wire scanners.
The second volume describes the other machines in the PS complex: the proton
linear accelerators, the PS Booster, the LEP pre-injector, the heavy-ion linac
and accumulator, and the antiproton rings.


title: Possible Evidence for Radial Flow of Heavy Mesons in d+Au Collisions

abstract:
  Recent measurements of particle correlations and the spectra of hadrons at
both RHIC and the LHC are suggestive of hydrodynamic behavior in very small
collision systems (p+Pb, d+Au and p+p collisions). The measurements are both
qualitatively and quantitatively similar to what is seen in central heavy ion
collisions where low viscosity hot nuclear matter is formed. While light quarks
and gluons are thought to make up the bulk matter, one of the most surprising
results in heavy ion collisions is that charm quarks also have a large $v_2$,
suggesting that they too participate in the matter. Measurements of the
transverse momentum spectra of electrons from the decay of $D$ and $B$ mesons
in d+Au show an enhancement in central collisions relative to p+p. We employ
the blast-wave model to determine if the flow of heavy quarks in d+Au and p+Pb
data is able to explain the enhancement observed in the data. We find a
reasonable description of the data with blast-wave parameters extracted from
fits to the light hadron spectra, suggesting hydrodynamics as a possible
explanation.


title:
Typical behavior of the linear programming method for combinatorial
  optimization problems: From a statistical-mechanical perspective

abstract:
  Typical behavior of the linear programming problem (LP) is studied as a
relaxation of the minimum vertex cover problem, which is a type of the integer
programming problem (IP). To deal with the LP and IP by statistical mechanics,
a lattice-gas model on the Erd\"os-R\'enyi random graphs is analyzed by a
replica method. It is found that the LP optimal solution is typically equal to
that of the IP below the critical average degree c*=e in the thermodynamic
limit. The critical threshold for LP=IP is beyond a mathematical result, c=1,
and coincides with the replica-symmetry-breaking threshold of the IP.

categories: cond-mat.dis-nn cond-mat.stat-mech cs.IT math.IT


title: Constituent quark model description of charmonium phenomenology

abstract:
  We review how quark models are able to describe the phenomenology of the
charm meson sector. The spectroscopy and decays of charmonium and open charm
mesons are described in a particular quark model and compared with the data and
the results of other existing models in the literature. A quite reasonable
global description of the heavy meson spectra is reached. A new assignment of
the $\psi(4415)$ resonance as a 3D state leaving aside the 4S state to the
X(4360) is tested through the analysis of the resonance structure in
$e^{+}e^{-}$ exclusive reactions around the $\psi(4415)$ energy region. We make
tentative assignments of some of the $XYZ$ mesons. To elucidate the structure
of the $1^{+}$ $c\bar{s}$ states, i.e. $D_{s1}(2460)$ and $D_{s1}(2536)$, we
study the strong decay properties of the $D_{s1}(2536)$ meson. We also perform
a calculation of the branching fractions for the semileptonic decays of $B$ and
$B_{s}$ mesons into final states containing orbitally excited charmed and
charmed-strange mesons, which have become a very important source of
information about the structure of heavy mesons. Analysis of the nonleptonic
$B$ meson decays into $D^{(\ast)}D_{sJ}$ are also included.


title: Inclusion-exclusion enhanced by nerve stimulation

abstract:
  When evaluating the lengthy inclusion-exclusion expansion many of its terms
may turn out to be zero, and hence should be discarded beforehand. Often this
can be done. The main idea is that the index sets of nonzero terms constitute a
set ideal (called the 'nerve'), which often can be encoded in a compact way
(Upgrade B). As a further enhancement (Upgrade A), equal nonzero terms can
sometimes be efficiently collected.


title: Structure and dynamics of core-periphery networks

abstract:
  Recent studies uncovered important core/periphery network structures
characterizing complex sets of cooperative and competitive interactions between
network nodes, be they proteins, cells, species or humans. Better
characterization of the structure, dynamics and function of core/periphery
networks is a key step of our understanding cellular functions, species
adaptation, social and market changes. Here we summarize the current knowledge
of the structure and dynamics of "traditional" core/periphery networks,
rich-clubs, nested, bow-tie and onion networks. Comparing core/periphery
structures with network modules, we discriminate between global and local
cores. The core/periphery network organization lies in the middle of several
extreme properties, such as random/condensed structures, clique/star
configurations, network symmetry/asymmetry, network
assortativity/disassortativity, as well as network hierarchy/anti-hierarchy.
These properties of high complexity together with the large degeneracy of core
pathways ensuring cooperation and providing multiple options of network flow
re-channelling greatly contribute to the high robustness of complex systems.
Core processes enable a coordinated response to various stimuli, decrease
noise, and evolve slowly. The integrative function of network cores is an
important step in the development of a large variety of complex organisms and
organizations. In addition to these important features and several decades of
research interest, studies on core/periphery networks still have a number of
unexplored areas.

categories: physics.soc-ph cs.NI cs.SI nlin.AO q-bio.MN


title: A new financial metric for the art market

abstract:
  This paper introduces a new financial metric for the art market. The metric
is based on the price per unit of area and is applicable to two-dimensional art
objects such as paintings.


title: The Four Color Theorem and Trees

abstract:
  Connection of the Four Color Theorem (FCT) with some operations on trees is
described. L.H. Kauffman's theorem about FCT and vector cross product is
discussed. Operation of transplantation on trees linked with the move of
brackets according to the associative law is used to formulate a conjecture.
When map is represented as a tying of the trees this conjecture proposes the
existence of special coloring of this map. This coloring makes possible
successive transplantations such that one of these trees is transformed to
another, and all the intermediate maps are colored properly. It means (in terms
of L.H. Kauffman) that not only for two different positions of brackets in a
product of n factors the associative law works (on special values of factors)
but also there is a way of moving brackets that for all intermediate
positioning of brackets the associative law is obeyed. Some classes of trees
for which the conjecture is proved are presented.


title: On Alpert Multiwavelets

abstract:
  The multiresolution analysis of Alpert is considered. Explicit formulas for
the entries in the matrix coefficients of the refinement equation are given in
terms of hypergeometric functions. These entries are shown to solve generalized
eigenvalue equations as well as partial difference equations. The matrix
coefficients in the wavelet equation are also considered and conditions are
given to obtain a unique solution.


title: A Combined Astrometric and Spectroscopic Study of Metal-Poor Binaries

abstract:
  In this work we present a study of binary systems in a metal-poor sample of
solar type stars. The stars analyzed were rejected from two planet search
samples because they were found to be binaries. Using available radial velocity
and Hipparcos astrometric data, we apply different methods to find, for every
binary system, a possible range of solutions for the mass of the companion and
its orbital period. In one case we find that the solution depends on the
Hipparcos data used: the old and new reductions give different results. Some
candidate low-mass companions are found, including some close to the brown
dwarf regime.


title: Estimating Undirected Graphs Under Weak Assumptions

abstract:
  We consider the problem of providing nonparametric confidence guarantees for
undirected graphs under weak assumptions. In particular, we do not assume
sparsity, incoherence or Normality. We allow the dimension $D$ to increase with
the sample size $n$. First, we prove lower bounds that show that if we want
accurate inferences with low assumptions then there are limitations on the
dimension as a function of sample size. When the dimension increases slowly
with sample size, we show that methods based on Normal approximations and on
the bootstrap lead to valid inferences and we provide Berry-Esseen bounds on
the accuracy of the Normal approximation. When the dimension is large relative
to sample size, accurate inferences for graphs under low assumptions are not
possible. Instead we propose to estimate something less demanding than the
entire partial correlation graph. In particular, we consider: cluster graphs,
restricted partial correlation graphs and correlation graphs.


title:
Effects of the liquid-gas phase transition and cluster formation on the
  symmetry energy

abstract:
  Various definitions of the symmetry energy are introduced for nuclei, dilute
nuclear matter below saturation density and stellar matter, which is found in
compact stars or core-collapse supernovae. The resulting differences are
exemplified by calculations in a theoretical approach based on a generalized
relativistic density functional for dense matter. It contains nucleonic
clusters as explicit degrees of freedom with medium dependent properties that
are derived for light clusters from a quantum statistical approach. With such a
model the dissolution of clusters at high densities can be described. The
effects of the liquid-gas phase transition in nuclear matter and of cluster
formation in stellar matter on the density dependence of the symmetry energy
are studied for different temperatures. It is observed that correlations and
the formation of inhomogeneous matter at low densities and temperatures causes
an increase of the symmetry energy as compared to calculations assuming a
uniform uncorrelated spatial distribution of constituent baryons and leptons.


title: Probing renormalization group flows using entanglement entropy

abstract:
  In this paper we continue the study of renormalized entanglement entropy
introduced in [1]. In particular, we investigate its behavior near an IR fixed
point using holographic duality. We develop techniques which, for any static
holographic geometry, enable us to extract the large radius expansion of the
entanglement entropy for a spherical region. We show that for both a sphere and
a strip, the approach of the renormalized entanglement entropy to the IR fixed
point value contains a contribution that depends on the whole RG trajectory.
Such a contribution is dominant, when the leading irrelevant operator is
sufficiently irrelevant. For a spherical region such terms can be anticipated
from a geometric expansion, while for a strip whether these terms have
geometric origins remains to be seen.


title: Measuring Properties of Dark Matter at the LHC

abstract:
  We review various theoretical methods for measuring dark matter properties at
the Large Hadron Collider.


title: On the semicircular law of large dimensional random quaternion matrices

abstract:
  It is well known that Gaussian symplectic ensemble (GSE) is defined on the
space of $n\times n$ quaternion self-dual Hermitian matrices with Gaussian
random elements. There is a huge body of literature regarding this kind of
matrices. As a natural idea we want to get more universal results by removing
the Gaussian condition. For the first step, in this paper we prove that the
empirical spectral distribution of the common quaternion self-dual Hermitian
matrices tends to semicircular law. The main tool to establish the universal
result is given as a lemma in this paper as well.


title:
Modeling of conservative fields in piecewise infinite plate with a thin
  inclusion

abstract:
  In the article the formulas for the modeling of conservative fields in
piecewise infinite plate with a thin inclusion found. The accuracy of the found
formulas is of order equal to the thickness of the outer layer. The problem for
higher accuracy solved by means of asymptotic formulas.


title:
Reliable reconstruction of HIV-1 whole genome haplotypes reveals clonal
  interference and genetic hitchhiking among immune escape variants

abstract:
  Following transmission, HIV-1 evolves into a diverse population, and next
generation sequencing enables us to detect variants occurring at low
frequencies. Studying viral evolution at the level of whole genomes was
hitherto not possible because next generation sequencing delivers relatively
short reads. We here provide a proof of principle that whole HIV-1 genomes can
be reliably reconstructed from short reads, and use this to study the selection
of immune escape mutations at the level of whole genome haplotypes. Using
realistically simulated HIV-1 populations, we demonstrate that reconstruction
of complete genome haplotypes is feasible with high fidelity. We do not
reconstruct all genetically distinct genomes, but each reconstructed haplotype
represents one or more of the quasispecies in the HIV-1 population. We then
reconstruct 30 whole genome haplotypes from published short sequence reads
sampled longitudinally from a single HIV-1 infected patient. We confirm the
reliability of the reconstruction by validating our predicted haplotype genes
with single genome amplification sequences, and by comparing haplotype
frequencies with observed epitope escape frequencies. Phylogenetic analysis
shows that the HIV-1 population undergoes selection driven evolution, with
successive replacement of the viral population by novel dominant strains. We
demonstrate that immune escape mutants evolve in a dependent manner with
various mutations hitchhiking along with others. As a consequence of this
clonal interference, selection coefficients have to be estimated for complete
haplotypes and not for individual immune escapes.


title: Strong representation of weak convergence

abstract:
  Skorokhod's representation theorem states that if on a Polish space, there is
defined a weakly convergent sequence of probability measures
$\mu_n\stackrel{w}\to\mu_0,$ as $n\to \infty$, then there exist a probability
space $(\Omega, \mathscr F, P)$ and a sequence of random elements $X_n$ such
that $X_n\to X$ almost surely and $X_n$ has the distribution function $\mu_n$,
$n=0,1,2,\cdots$. In this paper, we shall extend the Skorokhod representation
theorem to the case where if there are a sequence of separable metric spaces
$S_n$, a sequence of probability measures $\mu_n$ and a sequence of measurable
mappings $\varphi_n$ such that $\mu_n\varphi_n^{-1}\stackrel {w}\to\mu_0$, then
there exist a probability space $(\Omega,\mathscr F,P)$ and $S_n$-valued random
elements $X_n$ defined on $\Omega$, with distribution $\mu_n$ and such that
$\varphi_n(X_n)\to X_0$ almost surely. In addition, we present several
applications of our result including some results in random matrix theory,
while the original Skorokhod representation theorem is not applicable.


title: C*-algebras with norm controlled dual limits and nilpotent Lie groups

abstract:
  Motivated by the description of the C*-algebras of 5 dimensional nilpotent
Lie groups as algebras of operator fields defined over their spectra, we
introduce the family of C* -algebras with norm controlled dual limits and we
show that the C* -algebras of the 5 dimensional nilpotents Lie groups belong to
this class.


title: Quantum Interference in Plasmonic Circuits

abstract:
  Surface plasmon polaritons (plasmons) are a combination of light and a
collective oscillation of the free electron plasma at metal-dielectric
interfaces. This interaction allows sub-wavelength confinement of light, beyond
the diffraction limit inherent to dielectric structures. The resulting
electromagnetic fields are more intense and the strength of optical
interactions between metallic structures and light-sources or detectors can be
increased. Plasmons maintain non-classical photon statistics and preserve
entanglement on plasmon-assisted transmission through thin, patterned metallic
films or weakly confining waveguides. For quantum applications it is essential
that plasmons behave as indistinguishable quantum particles. Here we report on
a quantum interference experiment in a nanoscale plasmonic circuit consisting
of an on-chip plasmon beam splitter with integrated superconducting
single-photon detectors to allow efficient single plasmon detection. We
demonstrate quantum mechanical interaction between pairs of indistinguishable
plasmons by observing Hong-Ou-Mandel interference, a hallmark non-classical
effect which is the basis of linear optics-based quantum computation. Our work
shows that it is feasible to shrink quantum optical experiments to the
nanoscale and demonstrates a promising route for sub-wavelength quantum optical
networks.


title:
Empirical Potential Structure Refinement of semi-crystalline polymer
  systems: polytetrafluoroethylene and polychlorotrifluoroethylene

abstract:
  Empirical potential structure refinement (EPSR) simulations are performed on
total neutron scattering data from powder samples of polytetrafluoroethylene
(PTFE) and polychlorotrifluoroethylene (PCTFE), both at 300K. For PTFE a number
of Bragg peaks are visible in the scattering data and these are found to be
consistent with a lattice spacing $a(=b)=5.69(1)$\AA\ with a dihedral angle
along the (helical) chain of 166$^\circ$ which gives a repeat distance along
the chain (c-axis) of $\sim$19.6\AA. The positions of the Bragg peaks are well
reproduced by this model, although there is a mismatch in the amplitudes of
some of the higher order reflections between simulation and data. For PCTFE
there is only one visible Bragg peak (100) which is well reproduced by a
hexagonal lattice of atactic parallel polymers with a spacing of
$a(=b)=6.37(1)$\AA. In this case the absence of distinct reflections along the
polymer c-axis makes characterisation of the internal dihedral angle difficult,
but a model with nearly straight \textit{trans} (zig-zag) structure gives best
agreement with the data. For PCTFE little change in structure could be
discerned when the material was heated to 550K, apart from a slight increase in
lattice spacing. In both cases there is substantial diffuse scattering between
the Bragg peaks, and this is correctly replicated by the EPSR simulations.


title:
From the sandwiched quantum relative Tsallis entropy to its conditional
  form: Separability criterion beyond local and global spectra

abstract:
  The quantum relative Renyi entropy of two density matrices was recently
extended when the two do not commute, from which a conditional entropy is
identified. This is here extended to the corresponding Tsallis relative entropy
and to its conditional form. This new expression of Tsallis conditional entropy
is shown to witness entanglement beyond the method based on global and local
spectra of composite quantum states. When the reduced density matrix happens to
be a maximally mixed state, this conditional entropy coincides with the
expression in terms of Tsallis entropies derived earlier by Abe and Rajagopal
(Physica A 289, 157 (2001)). Separability range in one parameter family of W
and GHZ states with 3 and 4 qubits is explored here and it is shown that the
results inferred from negative Tsallis conditional entropy matches with that
obtained through Peres partial transpose criteria for one-parameter family of W
states, in one of its partitions. The criteria is shown to be non-spectral
through its usefulness in identifying entanglement in isospectral density
matrices.


title: On an inverse problem for scalar conservation laws

abstract:
  We study in what sense one can determine the function $k=k(x)$ in the scalar
hyperbolic conservation law $u_t+(k(x)f(u))_x=0$ by observing the solution
$u(t,\dott)$ of the Cauchy problem with initial data $u|_{t=0}=u_o$.


title:
Using field theory to construct hybrid particle-continuum simulation
  schemes with adaptive resolution for soft matter systems

abstract:
  We develop a multiscale hybrid scheme for simulations of soft condensed
matter systems, which allows one to treat the system at the particle level in
selected regions of space, and at the continuum level elsewhere. It is derived
systematically from an underlying particle-based model by field theoretic
methods. Particles in different representation regions can switch
representations on the fly, controlled by a spatially varying tuning function.
As a test case, the hybrid scheme is applied to simulate colloid-polymer
composites with high resolution regions close to the colloids. The hybrid
simulations are significantly faster than reference simulations of a pure
particle-based model, and the results are in good agreement.


title:
Partial Model Checking using Networks of Labelled Transition Systems and
  Boole an Equation Systems

abstract:
  Partial model checking was proposed by Andersen in 1995 to verify a temporal
logic formula compositionally on a composition of processes. It consists in
incrementally incorporating into the formula the behavioural information taken
from one process - an operation called quotienting - to obtain a new formula
that can be verified on a smaller composition from which the incorporated
process has been removed. Simplifications of the formula must be applied at
each step, so as to maintain the formula at a tractable size. In this paper, we
revisit partial model checking. First, we extend quotienting to the network of
labelled transition systems model, which subsumes most parallel composition
operators, including m-among-n synchronisation and parallel composition using
synchronisation interfaces, available in the ELOTOS standard. Second, we
reformulate quotienting in terms of a simple synchronous product between a
graph representation of the formula (called formula graph) and a process, thus
enabling quotienting to be implemented efficiently and easily, by reusing
existing tools dedicated to graph compositions. Third, we propose
simplifications of the formula as a combination of bisimulations and reductions
using Boolean equation systems applied directly to the formula graph, thus
enabling formula simplifications also to be implemented efficiently. Finally,
we describe an implementation in the CADP (Construction and Analysis of
Distributed Processes) toolbox and present some experimental results in which
partial model checking uses hundreds of times less memory than on-the-fly model
checking.


title: Photon propagation in a cold axion condensate

abstract:
  We discuss some striking properties of photons propagating in a cold axion
condensate oscillating coherently in time with a frequency $1/m_a$. Three
effects are discussed in this contribution: (a) due to the time dependence of
the background, photons moving in the cold axion background have no definite
energies and some momenta are not accessible to them. (b) we investigate the
combined influence of a magnetic field and the cold axion background and
propose a possible interferometric experiment to detect the latter. (c) if the
axion condensate has a space dependence, the photon refraction index is
modified in the medium, possibly leading to total reflection at the interface
with the ordinary vacuum.


title:
Tiled Array of Pixelated CZT Imaging Detectors for ProtoEXIST2 and
  MIRAX-HXI

abstract:
  We have assembled a tiled array (220 cm2) of fine pixel (0.6 mm) imaging CZT
detectors for a balloon borne wide-field hard X-ray telescope, ProtoEXIST2.
ProtoEXIST2 is a prototype experiment for a next generation hard X-ray imager
MIRAX-HXI on board Lattes, a spacecraft from the Agencia Espacial Brasilieira.
MIRAX will survey the 5 to 200 keV sky of Galactic bulge, adjoining southern
Galactic plane and the extragalactic sky with 6' angular resolution. This
survey will open a vast discovery space in timing studies of accretion neutron
stars and black holes. The ProtoEXIST2 CZT detector plane consists of 64 of 5
mm thick 2 cm x 2 cm CZT crystals tiled with a minimal gap. MIRAX will consist
of 4 such detector planes, each of which will be imaged with its own
coded-aperture mask. We present the packaging architecture and assembly
procedure of the ProtoEXIST2 detector. On 2012, Oct 10, we conducted a
successful high altitude balloon experiment of the ProtoEXIST1 and 2
telescopes, which demonstrates their technology readiness for space
application. During the flight both telescopes performed as well as on the
ground. We report the results of ground calibration and the initial results for
the detector performance in the balloon flight.


title: Ray tracing in FLRW flat space-times

abstract:
  In this work we take moves from the debate triggered by Melia et al [9]. and
followed by opposite comments by Lewis and Oirschot [10,11]. The point in
question regards the role of the Hubble horizon as a limit for observability in
a cosmological setting. We propose to take the issue in a broader way by
relating it to the causal character of the Hubble surface and to the tracing of
null trajectories, focusing on both three-fluids and generalized Chaplygin gas
models. The results should make clear that light rays reaching a comoving
observer at R(t_0)=0 have never travelled a distance greater than the areal
radius of the horizon until t_0.


title: Testing Chameleons Using Neutron Interferometry

abstract:
  Chameleons are a well motivated scalar field that might explain the observed
late time accelerated expansion of the universe. Chameleons possess the
interesting property that their mass, and hence interaction range, is dependent
on the density of their environment. One very appealing feature of chameleons
is the potential to test a model of dark energy in a laboratory setting. Here
we briefly review two proposed experiments to search for chameleons using
neutron interferometry techniques for the Snowmass 2013 Community Summer Study.


title: Sweedler Theory for (co)algebras and the bar-cobar constructions

abstract:
  We prove that the category of dg-coalgebras is symmetric monoidal closed and
that the category of dg-algebras is enriched, tensored, cotensored and strongly
monoidal over that of coalgebras. We apply this formalism to reconstruct
several known adjunctions, notably the bar-cobar adjunction.


title:
Effects of periodic scattering potential on Landau quantization and
  ballistic transport of electrons in graphene

abstract:
  A two-dimensional periodic array of scatterers has been introduced to a
single layer of graphene in the presence of an external magnetic field
perpendicular to the graphene layer. The eigenvalue equation for such a system
has been solved numerically to display the structure of split Landau subbands
as functions of both wave number and magnetic flux. The effects of pseudo-spin
coupling and Landau subbands mixing by a strong scattering potential have been
demonstrated. Additionally, we investigated the square barrier tunneling
problem when magnetic field is present, as well as demonstrate the crucial
difference in the modulated band structure between graphene and the
twodimensional electron gas. The low-magnetic field regime is particularly
interesting for Dirac fermions and has been discussed. Tunneling of Dirac
electrons through a magnetic potential barrier has been investigated to
complement the reported results on electrostatic potential scattering in the
presence of an ambient magnetic field.


title:
Interaction of two systems with saddle-node bifurcations on invariant
  circles. I. Foundations and the mutualistic case

abstract:
  The saddle-node bifurcation on an invariant circle (SNIC) is one of the
codimension-one routes to creation or destruction of a periodic orbit in a
continuous-time dynamical system. It governs the transition from resting
behaviour to periodic spiking in many class I neurons, for example. Here, as a
first step towards theory of networks of such units the effect of weak coupling
between two systems with a SNIC is analysed. Two crucial parameters of the
coupling are identified, which we call \delta_1 and \delta_2. Global
bifurcation diagrams are obtained here for the "mutualistic" case \delta_1
\delta_2 > 0. According to the parameter regime, there may coexist resting and
periodic attractors, and there can be quasiperiodic attractors of torus or
cantorus type, making the behaviour of even such a simple system quite
non-trivial. In a second paper we will analyse the mixed case \delta_1 \delta_2
< 0 and summarise the conclusions of this study.


title: The merging of the islands of inversion at N=20 and N=28

abstract:
  The N=20 and N=28 "islands of inversion" are described by large scale shell
model calculations with an extension of the interaction sdpf-u that makes it
possible to mix configurations with different Nhw or equivalently with
different number of particles promoted from the sd-shell to the pf-shell. It
allows to connect the classical sd-shell calculations below N=18 with the
sd(protons)-pf(neutrons) calculations beyond N=24-26, for all the isotopes from
Oxygen to Calcium, using the same interaction. For some isotopes this range
contains all the nuclei between the proton and the neutron drip lines and
includes the N=20 and N=28 islands of inversion. We shall pay particular
attention to the properties of the states at fix Nhw which turn out to be the
real protagonists of the physics at N=20. The existence of islands of
inversion/deformation will be explained as the result of the competition
between the spherical mean field which favors the 0hw configurations and the
nuclear correlations which favor the deformed Nhw configurations. The Magnesium
chain is exceptional because in it, the N=20 and N=28 "islands of inversion"
merge, enclosing all the isotopes between N=19 and N=30. Indeed, this would be
also the case for the Neon and Sodium chains if their drip lines would reach
N=28.


title:
Proper holomorphic embeddings into Stein manifolds with the density
  property

abstract:
  We prove that a Stein manifold of dimension $d$ admits a proper holomorphic
embedding into any Stein manifold of dimension at least $2d+1$ satisfying the
holomorphic density property. This generalizes classical theorems of Remmert,
Bishop and Narasimhan pertaining to embeddings into complex Euclidean spaces,
as well as several other recent results.


title: Frieden wave function representations via an EPR-Bohm experiment

abstract:
  The appearance of the spin-1/2 and spin-1 representations in the
Frieden-Soffer extreme physical information (EPI) statistical approach to the
Einstein-Podolsky-Rosen-Bohm (EPR-Bohm) experiment is shown. In order to obtain
the EPR-Bohm result, in addition to the observed structural and variational
information principles of the EPI method, the condition of the regularity of
the probability distribution is used. The observed structural information
principle is obtained from the analyticity of the logarithm of the likelihood
function. It is suggested that, due to the self-consistent analysis of both
information principles, quantum mechanics is covered by the statistical
information theory. The estimation of the angle between the analyzers in the
EPR-Bohm experiment is discussed.


title: Constraining Supersymmetry using the relic density and the Higgs boson

abstract:
  Recent measurements by Planck, LHC experiments, and Xenon100 have significant
impact on supersymmetric models and their parameters. We first illustrate the
constraints in the mSUGRA plane and then perform a detailed analysis of the
general MSSM with 13 free parameters. Using SFitter, Bayesian and Profile
Likelihood approaches are applied and their results compared. The allowed
structures in the parameter spaces are largely defined by different mechanisms
of dark matter annihilation in combination with the light Higgs mass
prediction. In mSUGRA the pseudoscalar Higgs funnel and stau co-annihilation
processes are still avoiding experimental pressure. In the MSSM stau
co-annihilation, the light Higgs funnel, a mixed bino--higgsino region
including the heavy Higgs funnel, and a large higgsino region predict the
correct relic density. Volume effects and changes in the model parameters
impact the extracted mSUGRA and MSSM parameter regions in the Bayesian
analysis.


title:
Global exact controllability of a 1D Schr\"odinger equations with a
  polarizability term

abstract:
  We consider a quantum particle in a 1D interval submitted to a potential. The
evolution of this particle is controlled using an external electric field.
Taking into account the so-called polarizability term in the model (quadratic
with respect to the control), we prove global exact controllability in a
suitable space for arbitrary potential and arbitrary dipole moment. This term
is relevant both from the mathematical and physical points of view. The proof
uses tools from the bilinear setting and a perturbation argument.


title: Polarimetric studies of Comet C/2009 P1 (Garradd)

abstract:
  We present the optical imaging polarimetric observations of comet C/2009
P1(Garradd) at three different phase angles e.g., 28.2$^\circ$, 28.1$^\circ$
and 21.6$^\circ$. The observations were carried out using IUCAA Faint Object
Spectrograph and Camera mounted on Cassegrain focus of the 2-m Telescope of
IGO, IUCAA, Pune in R$_{comet}$, R photometric bands, on 21 and 22 March 2012
and ARIES Imaging Polarimeter mounted on Cassegrain focus of the 1.04-m
Sampurnanand Telescope of ARIES, Nainital in R photometric band, on 23 May
2012. We show the presence of a jet activity in the rotational gradient treated
image of comet Garradd at phase angle 28.1$^\circ$. These jets are mainly
oriented towards the Sun and extended up to $\sim$ 5100 km from the cometary
photocenter. The antisolar extension of jet seems to be fainter, which is
extended up to $\sim$ 1800 km. It is found that the comet Garradd shows
negative polarization at phase angle 21.6$^\circ$. The degree of polarization
derived for Garradd is in good agreement with other comets at nearly similar
phase angles e.g., comets 67P/Churyumov-Gerasimenko, 22P/Kopff, 1P/Halley,
C/1990 K1 (Levy), 4P/Faye, and C/1995 O1 (Hale-Bopp) at phase angle $\sim$
28$^\circ$, and 47P/Ashbrook-Jackson at phase angle $\sim$ 21.6$^\circ$,
respectively. It is also found that the degree of polarization of dusty coma of
comet Garradd at phase angle $\sim$ 28$^\circ$ is high but, not as high as in
the case of comet Hale-Bopp.


title:
Asymptotic analysis and sign changing bubble towers for Lane-Emden
  problems

abstract:
  We consider the semilinear Lane-Emden problem in a smooth bounded domain of
the plane. The aim of the paper is to analyze the asymptotic behavior of sign
changing solutions as the exponent p of the nonlinearity goes to infinity.
Among other results we show, under some symmetry assumptions on the domain,
that the positive and negative parts of a family of symmetric solutions
concentrate at the same point, as p goes to infinity, and the limit profile
looks like a tower of two bubbles given by a superposition of a regular and a
singular solution of the Liouville problem in the plane.


title:
Studying the Molecular Ambient towards the Young Stellar Object EGO
  G35.04-0.47

abstract:
  We are performing a systematic study of the interstellar medium around
extended green objects (EGOs), likely massive young stellar objects driving
outflows. EGO G35.04-0.47 is located towards a dark cloud at the northern-west
edge of an HII region. Recently, H2 jets were discovered towards this source,
mainly towards its southwest, where the H2 1-0 S(1) emission peaks. Therefore,
the source was catalogued as the Molecular Hydrogen emission-line object MHO
2429. In order to study the molecular ambient towards this star-forming site,
we observed a region around the aforementioned EGO using the Atacama
Submillimeter Telescope Experiment in the 12CO J=3--2, 13CO J=3--2, HCO+
J=4--3, and CS J=7--6 lines with an angular and spectral resolution of 22" and
0.11 km s-1, respectively. The observations revealed a molecular clump where
the EGO is embedded at v_LSR ~ 51 km s-1, in coincidence with the velocity of a
Class I 95 GHz methanol maser previously detected. Analyzing the 12CO line we
discovered high velocity molecular gas in the range from 34 to 47 km s-1, most
likely a blueshifted outflow driven by the EGO. The alignment and shape of this
molecular structure coincide with those of the southwest lobe of MHO 2429
mainly between 46 and 47 km s-1, confirming that we are mapping its CO
counterpart. Performing a SED analysis of EGO G35.04-0.47 we found that its
central object should be an intermediate-mass young stellar object accreting
mass at a rate similar to those found in some massive YSOs. We suggest that
this source can become a massive YSO.


title:
Single inclusive particle production at high energy from HERA data to
  proton-nucleus collisions

abstract:
  We study single inclusive hadron production in proton-proton and
proton-nucleus collisions in the CGC framework. The parameters in the
calculation are determined solely by standard nuclear geometry and by
electron-proton deep inelastic scattering data, which is fit using the running
coupling BK equation. We show that it is possible to obtain a good fit of the
HERA inclusive cross section also without an anomalous dimension in the initial
condition. We argue that one must consistently use the proton transverse area
as measured by a high virtuality probe in DIS also for the single inclusive
cross section in proton-proton and proton-nucleus collisions. We show that this
leads to a midrapidity nuclear modification ratio R_pA that approaches unity at
high transverse momentum independently of sqrt(s), in contrast to most CGC
calculations in the literature. We also present predictions for future forward
R_pA measurements at the LHC.


title: Online Algorithms for Factorization-Based Structure from Motion

abstract:
  We present a family of online algorithms for real-time factorization-based
structure from motion, leveraging a relationship between incremental singular
value decomposition and recently proposed methods for online matrix completion.
Our methods are orders of magnitude faster than previous state of the art, can
handle missing data and a variable number of feature points, and are robust to
noise and sparse outliers. We demonstrate our methods on both real and
synthetic sequences and show that they perform well in both online and batch
settings. We also provide an implementation which is able to produce 3D models
in real time using a laptop with a webcam.


title: Fourier Coefficients Of Some Cusp Forms

abstract:
  The possible values of the nth Fourier coefficients a(n) of some cusp forms
f(z) of weight k => 12 are studied in this article. In particular, the values
of the tau function are investigated in some details, and proved that tau(p) =!
0 for all primes p => p_0.


title: Liftable integral closure

abstract:
  We develop the basic properties of an essentially new closure operation on
submodules, the \emph{liftable integral closure} of a submodule, including its
relationships with the two prevailing notions of integral closure of
submodules. We show that for a quite general class of local rings, every finite
length module may be represented as a quotient of the form $T/L$, where $T$ is
torsionless and integrally dependent on $L$.


title: Imperfect geometric control and overdamping for the damped wave equation

abstract:
  We consider the damped wave equation on a manifold with imperfect geometric
control. We show the sub-exponential energy decay estimate in
\cite{Chr-NC-erratum} is optimal in the case of one hyperbolic periodic
geodesic. We show if the equation is overdamped, then the energy decays
exponentially. Finally we show if the equation is overdamped but geometric
control fails for one hyperbolic periodic geodesic, then nevertheless the
energy decays exponentially.


title: Subspaces of $C^\infty$ invariant under the differentiation

abstract:
  Let $L$ be a proper differentiation invariant subspace of $C^\infty(a,b)$
such that the restriction operator $\frac{d}{dx}\bigl{|}_L$ has a discrete
spectrum $\Lambda$ (counting with multiplicities). We prove that $L$ is spanned
by functions vanishing outside some closed interval $I\subset(a,b)$ and
monomial exponentials $x^ke^{\lambda x}$ corresponding to $\Lambda$ if its
density does not exceed the critical value $\frac{|I|}{2\pi}$, and moreover, we
show that the result is not necessarily true when the density of $\Lambda$
equals the critical value. This answers a question posed by the first author
and B. Korenblum. Finally, if the residual part of $L$ is trivial, then $L$ is
spanned by the monomial exponentials it contains.


title:
Effect of paramagnetic fluctuations on a Fermi surface topological
  transition in two dimensions

abstract:
  We study the Fermi surface topological transition of the pocket-opening type
in a two dimensional Fermi liquid. We find that the paramagnetic fluctuations
in an interacting Fermi liquid typically drive the transition first order at
zero temperature. We first gain insight from a calculation using second order
perturbation theory in the self-energy. This is valid for weak interaction and
far from instabilities. We then extend the results to stronger interaction,
using the self-consistent fluctuation approximation. Experimental signatures
are given in the light of these results.


title: Stellar Magnetic Dynamos and Activity Cycles

abstract:
  Using a new uniform sample of 824 solar and late-type stars with measured
X-ray luminosities and rotation periods we have studied the relationship
between rotation and stellar activity that is believed to be a probe of the
underlying stellar dynamo. Using an unbiased subset of the sample we calculate
the power law slope of the unsaturated regime of the activity -- rotation
relationship as $L_X/L_{bol}\propto Ro^\beta$, where $\beta=-2.70\pm0.13$. This
is inconsistent with the canonical $\beta = -2$ slope to a confidence of
5$\sigma$ and argues for an interface-type dynamo. We map out three regimes of
coronal emission as a function of stellar mass and age, using the empirical
saturation threshold and theoretical super-saturation thresholds. We find that
the empirical saturation timescale is well correlated with the time at which
stars transition from the rapidly rotating convective sequence to the slowly
rotating interface sequence in stellar spin-down models. This may be hinting at
fundamental changes in the underlying stellar dynamo or internal structure. We
also present the first discovery of an X-ray unsaturated, fully convective M
star, which may be hinting at an underlying rotation - activity relationship in
fully convective stars hitherto not observed. Finally we present early results
from a blind search for stellar X-ray cycles that can place valuable
constraints on the underlying ubiquity of solar-like activity cycles.


title: How Cold is Cold Dark Matter?

abstract:
  If cold dark matter consists of particles, these must be non-interacting and
non-relativistic by definition. In most cold dark matter models however, dark
matter particles inherit a non-vanishing velocity dispersion from interactions
in the early universe, a velocity that redshifts with cosmic expansion but
certainly remains non-zero. In this article, we place model-independent
constraints on the dark matter temperature to mass ratio, whose square root
determines the dark matter velocity dispersion. We only assume that dark matter
particles decoupled kinetically while non-relativistic, when galactic scales
had not entered the horizon yet, and that their momentum distribution has been
Maxwellian since that time. Under these assumptions, using cosmic microwave
background and matter power spectrum observations, we place upper limits on the
temperature to mass ratio of cold dark matter today (away from collapsed
structures). These limits imply that the present cold dark matter velocity
dispersion has to be smaller than 54 m/s. Cold dark matter has to be quite
cold, indeed.


title: Interdependent networks: the fragility of control

abstract:
  Recent work in the area of interdependent networks has focused on
interactions between two systems of the same type. However, an important and
ubiquitous class of systems are those involving monitoring and control, an
example of interdependence between processes that are very different. In this
Article, we introduce a framework for modelling distributed supervisory control
in the guise of an electrical network supervised by a distributed system of
control devices. The system is characterised by degrees of freedom salient to
real-world systems--- namely, the number of control devices, their inherent
reliability, and the topology of the control network. Surprisingly, the
behavior of the system depends crucially on the reliability of control devices.
When devices are completely reliable, cascade sizes are percolation controlled;
the number of devices being the relevant parameter. For unreliable devices, the
topology of the control network is important and can dramatically reduce the
resilience of the system.


title:
Sample path behavior of a L\'evy insurance risk process approaching
  ruin, under the Cram\'er-Lundberg and convolution equivalent conditions

abstract:
  Recent studies have demonstrated an interesting connection between the
asymptotic behavior at ruin of a L\'evy insurance risk process under the
Cram\'er-Lundberg and convolution equivalent conditions. For example, the
limiting distributions of the overshoot and the undershoot are strikingly
similar in these two settings. This is somewhat surprising since the global
sample path behavior of the process under these two conditions is quite
different. Using tools from excursion theory and fluctuation theory, we provide
a means of transferring results from one setting to the other which, among
other things, explains this connection and leads to new asymptotic results.
This is done by describing the evolution of the sample paths from the time of
the last maximum prior to ruin until ruin occurs.


title: Pulsar Emission Spectrum

abstract:
  Emission spectrum is calculated for a weak axisymmetric pulsar. Also
calculated are the observed spectrum, efficiency, and the observed efficiency.
The underlying flow of electrons and positrons turns out to be curiously
intricate.


title:
Noise-induced quantum coherence drives photocarrier generation dynamics
  at polymeric semiconductor heterojunctions

abstract:
  We present a fully quantum-mechanical model of the electronic dynamics of
primary photoexcitations in a polymeric semiconductor heterojunction, which
includes both polymer stacking and phonon relaxation. By examining the
phonon-induced fluctuations in the state-to-state energy gaps and the exact
golden-rule rate constants, we conclude that resonant tunnelling between the
primary exciton to delocalized interchain charge-transfer states may be the
initial step in the formation of charge-carriers in polymer-based
bulk-heterojunction photovoltaic diodes.


title:
Efficient Algorithms for Robust and Stable Principal Component Pursuit
  Problems

abstract:
  The problem of recovering a low-rank matrix from a set of observations
corrupted with gross sparse error is known as the robust principal component
analysis (RPCA) and has many applications in computer vision, image processing
and web data ranking. It has been shown that under certain conditions, the
solution to the NP-hard RPCA problem can be obtained by solving a convex
optimization problem, namely the robust principal component pursuit (RPCP).
Moreover, if the observed data matrix has also been corrupted by a dense noise
matrix in addition to gross sparse error, then the stable principal component
pursuit (SPCP) problem is solved to recover the low-rank matrix. In this paper,
we develop efficient algorithms with provable iteration complexity bounds for
solving RPCP and SPCP. Numerical results on problems with millions of variables
and constraints such as foreground extraction from surveillance video, shadow
and specularity removal from face images and video denoising from heavily
corrupted data show that our algorithms are competitive to current
state-of-the-art solvers for RPCP and SPCP in terms of accuracy and speed.


title:
Spectral Properties and Local Density of States of Disordered Quantum
  Hall Systems with Rashba Spin-Orbit Coupling

abstract:
  We theoretically investigate the spectral properties and the spatial
dependence of the local density of states (LDoS) in disordered two-dimensional
electron gases (2DEG) in the quantum Hall regime, taking into account the
combined presence of electrostatic disorder, random Rashba spin-orbit in-
teraction, and finite Zeeman coupling. To this purpose, we extend a
coherent-state Green's function formalism previously proposed for spinless 2DEG
in the presence of smooth arbitrary disorder, that here incorporates the
nontrivial coupling between the orbital and spin degrees of freedom into the
electronic drift states. The formalism allows us to obtain analytical and
controlled nonperturbative expressions of the energy spectrum in arbitrary
locally flat disorder potentials with both random electric fields and Rashba
coupling. As an illustration of this theory, we derive analytical microscopic
expressions for the LDoS in different temperature regimes which can be used as
a starting point to interpret scanning tunneling spectroscopy data at high
magnetic fields. In this context, we study the spatial dependence and linewidth
of the LDoS peaks and explain an experimentally-noticed correlation between the
spatial dispersion of the spin-orbit splitting and the local extrema of the
potential landscape.