title: Baryon transition form factors at the pole

abstract:
  Electromagnetic resonance properties are uniquely defined at the pole and do
not depend on the separation of the resonance from background or the decay
channel. Photon-nucleon branching ratios are nowadays often quoted at the pole,
and we generalize the considerations to the case of virtual photons. We derive
and compare relations for nucleon to baryon transition form factors both for
the Breit-Wigner and the pole positions. Using the MAID2007 and SAID SM08
partial wave analyses of pion electroproduction data, we compare the $G_M$,
$G_E$, and $G_C$ form factors for the $\Delta(1232)$ resonance excitation at
the Breit-Wigner resonance and pole positions up to $Q^2=5$ GeV$^2$. We also
explore the $E/M$ and $S/M$ ratios as functions of $Q^2$. For pole and residue
extraction, we apply the Laurent + Pietarinen method.


title:
Conversational Contextual Cues: The Case of Personalization and History
  for Response Ranking

abstract:
  We investigate the task of modeling open-domain, multi-turn, unstructured,
multi-participant, conversational dialogue. We specifically study the effect of
incorporating different elements of the conversation. Unlike previous efforts,
which focused on modeling messages and responses, we extend the modeling to
long context and participant's history. Our system does not rely on handwritten
rules or engineered features; instead, we train deep neural networks on a large
conversational dataset. In particular, we exploit the structure of Reddit
comments and posts to extract 2.1 billion messages and 133 million
conversations. We evaluate our models on the task of predicting the next
response in a conversation, and we find that modeling both context and
participants improves prediction accuracy.


title: Deeper Depth Prediction with Fully Convolutional Residual Networks

abstract:
  This paper addresses the problem of estimating the depth map of a scene given
a single RGB image. We propose a fully convolutional architecture, encompassing
residual learning, to model the ambiguous mapping between monocular images and
depth maps. In order to improve the output resolution, we present a novel way
to efficiently learn feature map up-sampling within the network. For
optimization, we introduce the reverse Huber loss that is particularly suited
for the task at hand and driven by the value distributions commonly present in
depth maps. Our model is composed of a single architecture that is trained
end-to-end and does not rely on post-processing techniques, such as CRFs or
other additional refinement steps. As a result, it runs in real-time on images
or videos. In the evaluation, we show that the proposed model contains fewer
parameters and requires fewer training data than the current state of the art,
while outperforming all approaches on depth estimation. Code and models are
publicly available.


title:
Diffusion-controlled intrachain reactions in polymer: An analytical
  model

abstract:
  A theory of diffusion-controlled intramolecular reactions of polymer chain in
dilute solution is formulated. Our model is based on the widely used
diffusion-reaction formalism of Wilemski and Fixman (J. Chem. Phys. 60, 866
(1974). Our model is more general than the model proposed by Wilemski and
Fixman, in the sense that our model considers the motion of both close and open
chain polymer explicitely. It is quite unlikely that the motion of close chain
polymer do not play any role in the loop formation dynamics, but unfortunately
this fact was not considered in any of the earlier studies.


title: Weak Type Bound for Oscillatory Singular Integrals

abstract:
  Let $ T _{P} f (x) = \int e ^{i P (y)} K (y) f (x-y) \, dy $, where $ K (y)$
is a smooth Calder\'on-Zygmund kernel on $ \mathbb R ^{n}$, and $ P$ be a
polynomial. The maximal truncations of $ T_P$ satisfy the weak $ L ^{1}$
inequality, our proof simplifying and extending the argument of Chanillo and
Christ for the weak type bound for $ T_P$.


title:
On the periodicity of irreducible elements in arithmetical congruence
  monoids

abstract:
  Arithmetical congruence monoids, which arise in non-unique factorization
theory, are multiplicative monoids $M_{a,b}$ consisting of all positive
integers $n$ satsfying $n \equiv a \bmod b$. In this paper, we examine the
asymptotic behavior of the set of irreducible elements of $M_{a,b}$, and
characterize in terms of $a$ and $b$ when this set forms an eventually periodic
sequence.


title:
Bulk supertranslation memories: a concept reshaping the vacua and black
  holes of general relativity

abstract:
  The memory effect is a prediction of general relativity on the same footing
as the existence of gravitational waves. The memory effect is understood at
future null infinity as a transition induced by null radiation from a
Poincar\'e vacuum to another vacuum. Those are related by a supertranslation,
which is a fundamental symmetry of asymptotically flat spacetimes. In this
essay, I argue that finite supertranslation diffeomorphisms should be extended
into the bulk spacetime consistently with canonical charge conservation. It
then leads to fascinating geometrical features of gravitational Poincar\'e
vacua. I then argue that in the process of black hole merger or gravitational
collapse, dramatic but computable memory effects occur. They lead to a final
stationary metric which qualitatively deviates from the Schwarzschild metric.


title:
Charged Lepton Flavour Violation and Neutrinoless Double Beta Decay in
  Left-Right Symmetric Models with Type I+II Seesaw

abstract:
  We study the new physics contributions to neutrinoless double beta decay
($0\nu\beta \beta$) half-life and lepton flavour violation (LFV) amplitude
within the framework of the minimal left-right symmetric model (MLRSM).
Considering all possible new physics contributions to $0\nu\beta \beta$ and
charged lepton flavour violation $\mu \rightarrow e \gamma, \mu \rightarrow 3e$
in MLRSM, we constrain the parameter space of the model from the requirement of
satisfying existing experimental bounds. Assuming the breaking scale of the
left-right symmetry to be $\mathcal{O}(1)$ TeV accessible at ongoing and near
future collider experiments, we consider the most general type I+II seesaw
mechanism for the origin of tiny neutrino masses. Choosing the relative
contribution of the type II seesaw term allows us to calculate the right handed
neutrino mass matrix as well as Dirac neutrino mass matrix as a function of the
model parameters, required for the calculation of $0\nu\beta \beta$ and LFV
amplitudes. We show that such a general type I+II seesaw structure results in
more allowed parameter space compared to individual type I or type II seesaw
cases considered in earlier works. In particular, we show that the doubly
charged scalar masses $M_{\Delta}$ are allowed to be smaller than the heaviest
right handed neutrino mass $M_N$ from the present experimental bounds in these
scenarios which is in contrast to earlier results with individual type I or
type II seesaw showing $M_{\Delta} > M_N$.


title: Existence and convexity of solutions of the fractional heat equation

abstract:
  We prove that the initial-value problem for the fractional heat equation
admits a solution provided that the (possibly unbounded) initial datum has a
conveniently moderate growth at infinity. Under the same growth condition we
also prove that the solution is unique. Our result does not require any sign
assumption, thus complementing the Widder's type theorem of Barrios et al.
(Arch. Rational Mech. Anal. 213 (2014) 629-650) for positive solutions.
Finally, we show that the fractional heat flow preserves convexity of the
initial datum. Incidentally, several properties of stationary convex solutions
are established.


title: Modeling the Rise of Fibril Magnetic Fields in Fully Convective Stars

abstract:
  Many fully convective stars exhibit a wide variety of surface magnetism,
including starspots and chromospheric activity. The manner by which bundles of
magnetic field traverse portions of the convection zone to emerge at the
stellar surface is not especially well understood. In the Solar context, some
insight into this process has been gleaned by regarding the magnetism as
consisting partly of idealized thin flux tubes (TFT). Here, we present the
results of a large set of TFT simulations in a rotating spherical domain of
convective flows representative of a 0.3 solar-mass, main-sequence star. This
is the first study to investigate how individual flux tubes in such a star
might rise under the combined influence of buoyancy, convection, and
differential rotation. A time-dependent hydrodynamic convective flow field,
taken from separate 3D simulations calculated with the anelastic equations,
impacts the flux tube as it rises. Convective motions modulate the shape of the
initially buoyant flux ring, promoting localized rising loops. Flux tubes in
fully convective stars have a tendency to rise nearly parallel to the rotation
axis. However, the presence of strong differential rotation allows some
initially low latitude flux tubes of moderate strength to develop rising loops
that emerge in the near-equatorial region. Magnetic pumping suppresses the
global rise of the flux tube most efficiently in the deeper interior and at
lower latitudes. The results of these simulations aim to provide a link between
dynamo-generated magnetic fields, fluid motions, and observations of starspots
for fully convective stars.


title:
From trivial spectrum subspaces to spaces of diagonalizable real
  matrices

abstract:
  A recent generalization of Gerstenhaber's theorem on spaces of nilpotent
matrices is shown to yield a new proof of the classification of linear
subspaces of diagonalizable real matrices with the maximal dimension.


title: Validation of the CMS Magnetic Field Map

abstract:
  The Compact Muon Solenoid (CMS) is a general purpose detector, designed to
run at the highest luminosity at the CERN Large Hadron Collider (LHC). Its
distinctive features include a 4 T superconducting solenoid with 6-m-diameter
by 12.5-m-length free bore, enclosed inside a 10,000-ton return yoke made of
construction steel. The return yoke consists of five dodecagonal three-layered
barrel wheels and four end-cap disks at each end comprised of steel blocks up
to 620 mm thick, which serve as the absorber plates of the muon detection
system. To measure the field in and around the steel, a system of 22 flux loops
and 82 3-D Hall sensors is installed on the return yoke blocks. A TOSCA 3-D
model of the CMS magnet is developed to describe the magnetic field everywhere
outside the tracking volume measured with the field-mapping machine. The
magnetic field description is compared with the measurements and discussed.


title:
Exact steady states for quantum quenches in integrable Heisenberg spin
  chains

abstract:
  The study of quantum quenches in integrable systems has significantly
advanced with the introduction of the Quench Action method, a versatile
analytical approach to non-equilibrium dynamics. However, its application is
limited to those cases where the overlaps between the initial state and the
eigenstates of the Hamiltonian governing the time evolution are known exactly.
Conversely, in this work we consider physically interesting initial states for
which such overlaps are still unknown. In particular, we focus on different
classes of product states in spin-$1/2$ and spin-$1$ integrable chains, such as
tilted ferromagnets and antiferromagnets. We get around the missing overlaps by
following a recent approach based on the knowledge of complete sets of
quasi-local charges. This allows us to provide a closed-form analytical
characterization of the effective stationary state reached at long times after
the quench, through the Bethe ansatz distributions of particles and holes. We
compute the asymptotic value of local correlations and check our predictions
against numerical data.


title: Support Theorem for the Light Ray Transform on Minkowski Spaces

abstract:
  We study the Light-Ray transform of integrating vector fields on the
Minkowski time-space R^{1+n}, n bigger than equal 2, with the Minkowski metric.
We prove a support theorem for vector fields vanishing on an open set of
light-like geodesics.


title: Some cut-generating functions for second-order conic sets

abstract:
  In this paper, we study cut generating functions for conic sets. Our first
main result shows that if the conic set is bounded, then cut generating
functions for integer linear programs can easily be adapted to give the integer
hull of the conic integer program. Then we introduce a new class of cut
generating functions which are non-decreasing with respect to second-order
cone. We show that, under some minor technical conditions, these functions
together with integer linear programming-based functions are sufficient to
yield the integer hull of intersections of conic sections in $\mathbb{R}^2$.


title:
Stimulated emission of fast Alfv\'en waves within magnetically confined
  fusion plasmas

abstract:
  A fast Alfv\'en wave with finite amplitude is shown to grow by a stimulated
emission process that we propose for exploitation in toroidal magnetically
confined fusion plasmas. Stimulated emission occurs while the wave propagates
inward through the outer mid-plane plasma, where a population inversion of the
energy distribution of fusion-born ions is observed to arise naturally. Fully
nonlinear first principles simulations, which self-consistently evolve
particles and fields under the Maxwell-Lorentz system, demonstrate this novel
"alpha-particle channelling" scenario for the first time.


title: Novel Sampling Design for Respondent-driven Sampling

abstract:
  Respondent-driven sampling (RDS) is a method of chain referral sampling
popular for sampling hidden and/or marginalized populations. As such, even
under the ideal sampling assumptions, the performance of RDS is restricted by
the underlying social network: if the network is divided into communities that
are weakly connected to each other, then RDS is likely to oversample one of
these communities. In order to diminish the "referral bottlenecks" between
communities, we propose anti-cluster RDS (AC-RDS), an adjustment to the
standard RDS implementation. Using a standard model in the RDS literature,
namely, a Markov process on the social network that is indexed by a tree, we
construct and study the Markov transition matrix for AC-RDS. We show that if
the underlying network is generated from the Stochastic Blockmodel with equal
block sizes, then the transition matrix for AC-RDS has a larger spectral gap
and consequently faster mixing properties than the standard random walk model
for RDS. In addition, we show that AC-RDS reduces the covariance of the samples
in the referral tree compared to the standard RDS and consequently leads to a
smaller variance and design effect. We confirm the effectiveness of the new
design using both the Add-Health networks and simulated networks.


title:
Ground-State Ordering of the $J_1$--$J_2$ Model on the Simple Cubic and
  Body-Centered Cubic Lattices

abstract:
  The $J_1$--$J_2$ Heisenberg model is a "canonical" model in the field of
quantum magnetism in order to study the interplay between frustration and
quantum fluctuations as well as quantum phase transitions driven by
frustration. Here we apply the Coupled Cluster Method (CCM) to study the
spin-half $J_1$--$J_2$ model with antiferromagnetic nearest-neighbor bonds $J_1
>0$ and next-nearest-neighbor bonds $J_2 >0$ for the simple cubic (SC) and
body-centered cubic (BCC) lattices. In particular, we wish to study the
ground-state ordering of these systems as a function of the frustration
parameter $p=z_2J_2/z_1J_1$, where $z_1$ ($z_2$) is the number of nearest
(next-nearest) neighbors. We wish to determine the positions of the phase
transitions using the CCM and we aim to resolve the nature of the phase
transition points. We consider the ground-state energy, order parameters,
spin-spin correlation functions as well as the spin stiffness in order to
determine the ground-state phase diagrams of these models. We find a direct
first-order phase transition at a value of $p = 0.528$ from a state of
nearest-neighbor N\'eel order to next-nearest-neighbor N\'eel order for the BCC
lattice. For the SC lattice the situation is more subtle. CCM results for the
energy, the order parameter, the spin-spin correlation functions and the spin
stiffness indicate that there is no direct first-order transition between
ground-state phases with magnetic long-range order, rather it is more likely
that two phases with antiferromagnetic long-range are separated by a narrow
region of a spin-liquid like quantum phase around $p=0.55$. Thus the strong
frustration present in the $J_1$--$J_2$ Heisenberg model on the SC lattice may
open a window for an unconventional quantum ground state in this
three-dimensional spin model.


title: Stream Clipper: Scalable Submodular Maximization on Stream

abstract:
  We propose a streaming submodular maximization algorithm "stream clipper"
that performs as well as the offline greedy algorithm on document/video
summarization in practice. It adds elements from a stream either to a solution
set $S$ or to an extra buffer $B$ based on two adaptive thresholds, and
improves $S$ by a final greedy step that starts from $S$ adding elements from
$B$. During this process, swapping elements out of $S$ can occur if doing so
yields improvements. The thresholds adapt based on if current memory
utilization exceeds a budget, e.g., it increases the lower threshold, and
removes from the buffer $B$ elements below the new lower threshold. We show
that, while our approximation factor in the worst case is $1/2$ (like in
previous work, and corresponding to the tight bound), we show that there are
data-dependent conditions where our bound falls within the range $[1/2,
1-1/e]$. In news and video summarization experiments, the algorithm
consistently outperforms other streaming methods, and, while using
significantly less computation and memory, performs similarly to the offline
greedy algorithm.


title: Modal formulation for diffraction by absorbing photonic crystal slabs

abstract:
  A finite element-based modal formulation of diffraction of a plane wave by an
absorbing photonic crystal slab of arbitrary geometry is developed for
photovoltaic applications. The semi-analytic approach allows efficient and
accurate calculation of the absorption of an array with a complex unit cell.
This approach gives direct physical insight into the absorption mechanism in
such structures, which can be used to enhance the absorption. The verification
and validation of this approach is applied to a silicon nanowire array and the
efficiency and accuracy of the method is demonstrated. The method is ideally
suited to studying the manner in which spectral properties (e.g., absorption)
vary with the thickness of the array, and we demonstrate this with efficient
calculations which can identify an optimal geometry.


title:
Comment on "Benchmarking Compressed Sensing, Super-Resolution, and
  Filter Diagonalization"

abstract:
  In a recent paper [Int. J. Quant. Chem. (2016) DOI: 10.1002/qua.25144,
arXiv:1502.06579] Markovich, Blau, Sanders, and Aspuru-Guzik presented a
numerical evaluation and comparison of three methods, Compressed Sensing (CS),
Super-Resolution (SR), and Filter Diagonalization (FDM), on their ability of
"recovering information" from time signals, concluding that CS and RS
outperform FDM. We argue that this comparison is invalid for the following
reasons. FDM is a well established method designed for solving the harmonic
inversion problem or, similarly, for the problem of spectral estimation, and as
such should be applied only to problems of this kind. The authors incorrectly
assume that the problem of data fitting is equivalent to the spectral
estimation problem, regardless of what parametric form is used, and,
consequently, in all five numerical examples FDM is applied to the wrong
problem. Moreover, the authors' implementation of FDM turned out to be
incorrect, leading to extremely bad results, caused by numerical instabilities.
As we demonstrate here, if implemented correctly, FDM could still be used for
fitting the data, at least for the time signals composed of damped sinusoids,
resulting in superior performance. In addition, we show that the published
article is full of inaccuracies, mistakes and incorrect statements.


title:
Quantification of uncertainty in first-principles predicted mechanical
  properties of solids: Application to solid ion conductors

abstract:
  Computationally-guided material discovery is being increasingly employed
using a descriptor-based screening through the calculation of a few properties
of interest. A precise understanding of the uncertainty associated with first
principles density functional theory calculated property values is important
for the success of descriptor-based screening. Bayesian error estimation
approach has been built-in to several recently developed exchange-correlation
functionals, which allows an estimate of the uncertainty associated with
properties related to the ground state energy, for e.g. adsorption energies.
Here, we propose a robust and computationally efficient method for quantifying
uncertainty in mechanical properties, which depends on the derivatives of the
energy. The procedure involves calculating the energy around the equilibrium
cell volume with different strains and fitting the obtained energies to the
corresponding energy-strain relationship. At each strain, we use instead of a
single energy, an ensemble of energies, giving us an ensemble of fits and
thereby, an ensemble of mechanical properties associated with each fit, whose
spread can be used to quantify its uncertainty. The generation of ensemble of
energies is only a post-processing step involving a perturbation of parameters
of the exchange-correlation functional and solving for the energy non-self
consistently. The proposed method is computationally efficient and provides a
more robust uncertainty estimate compared to the approach of self-consistent
calculations employing several different exchange-correlation functionals. We
demonstrate the method by calculating the uncertainty bounds for Si using the
developed method. We show that the calculated uncertainty bounds the property
values obtained using three different GGA functionals: PBE, PBEsol and RPBE.


title:
GammaLib and ctools: A software framework for the analysis of
  astronomical gamma-ray data

abstract:
  The field of gamma-ray astronomy has seen important progress during the last
decade, yet there exists so far no common software framework for the scientific
analysis of gamma-ray telescope data. We propose to fill this gap by means of
the GammaLib software, a generic library that we have developed to support the
analysis of gamma-ray event data. GammaLib has been written in C++ and all
functionality is available in Python through an extension module. On top of
this framework we have developed the ctools software package, a suite of
software tools that enables building of flexible workflows for the analysis of
Imaging Air Cherenkov Telescope event data. The ctools are inspired by science
analysis software available for existing high-energy astronomy instruments, and
they follow the modular ftools model developed by the High Energy Astrophysics
Science Archive Research Center. The ctools have been written in Python and
C++, and can be either used from the command line, via shell scripts, or
directly from Python. In this paper we present the GammaLib and ctools software
versions 1.0 that have been released end of 2015. GammaLib and ctools are ready
for the science analysis of Imaging Air Cherenkov Telescope event data, and
also support the analysis of Fermi-LAT data and the exploitation of the COMPTEL
legacy data archive. We propose to use ctools as the Science Tools software for
the Cherenkov Telescope Array Observatory.


title: Supergravity background of the lambda-deformed AdS_3 x S^3 supercoset

abstract:
  We construct the solution of type IIB supergravity describing the integrable
lambda-deformation of the AdS_3 x S^3 supercoset. While the geometry
corresponding to the deformation of the bosonic coset has been found in the
past, our background is more natural for studying superstrings, and several
interesting features distinguish our solution from its bosonic counterpart. We
also report progress towards constructing the lambda-deformation of the AdS_5 x
S^5 supercoset.


title: On feebly compact topologies on the semilattice $\exp_n\lambda$

abstract:
  We study feebly compact topologies $\tau$ on the semilattice
$\left(\exp_n\lambda,\cap\right)$ such that $\left(\exp_n\lambda,\tau\right)$
is a semitopological semilattice. All compact semilattice $T_1$-topologies on
$\exp_n\lambda$ are described. Also we prove that for an arbitrary positive
integer $n$ and an arbitrary infinite cardinal $\lambda$ for a $T_1$-topology
$\tau$ on $\exp_n\lambda$ the following conditions are equivalent: $(i)$
$\left(\exp_n\lambda,\tau\right)$ is a compact topological semilattice; $(ii)$
$\left(\exp_n\lambda,\tau\right)$ is a countably compact topological
semilattice; $(iii)$ $\left(\exp_n\lambda,\tau\right)$ is a feebly compact
topological semilattice; $(iv)$ $\left(\exp_n\lambda,\tau\right)$ is a compact
semitopological semilattice; $(v)$ $\left(\exp_n\lambda,\tau\right)$ is a
countably compact semitopological semilattice. We construct a countably
pracompact $H$-closed quasiregular non-semiregular topology
$\tau_{\operatorname{\textsf{fc}}}^2$ such that
$\left(\exp_2\lambda,\tau_{\operatorname{\textsf{fc}}}^2\right)$ is a
semitopological semilattice with discontinuous semilattice operation and prove
that for an arbitrary positive integer $n$ and an arbitrary infinite cardinal
$\lambda$ every $T_1$-semiregular feebly compact semitopological semilattice
$\exp_n\lambda$ is a compact topological semilattice.


title: DINAMITE: A modern approach to memory performance profiling

abstract:
  Diagnosing and fixing performance problems on multicore machines with deep
memory hierarchies is extremely challenging. Certain problems are best
addressed when we can analyze the entire trace of program execution, e.g.,
every memory access. Unfortunately such detailed execution logs are very large
and cannot be analyzed by direct inspection. We present DINAMITE: a toolkit for
Dynamic INstrumentation and Analysis for MassIve Trace Exploration. DINAMITE is
a collection of tools for end-to-end performance analysis: from the LLVM
compiler pass that instruments the program to plug-and-play tools that use a
modern data analytics engine Spark Streaming for trace introspection. Using
DINAMITE we found opportunities to improve data layout in several applications
that resulted in 15-20% performance improvements and found a shared-variable
bottleneck in a popular key-value store, whose elimination improved performance
by 20x.


title:
Duplication-Correcting Codes for Data Storage in the DNA of Living
  Organisms

abstract:
  The ability to store data in the DNA of a living organism has applications in
a variety of areas including synthetic biology and watermarking of patented
genetically-modified organisms. Data stored in this medium is subject to errors
arising from various mutations, such as point mutations, indels, and tandem
duplication, which need to be corrected to maintain data integrity. In this
paper, we provide error-correcting codes for errors caused by tandem
duplications, which create a copy of a block of the sequence and insert it in a
tandem manner, i.e., next to the original. In particular, we present two
families of codes for correcting errors due to tandem-duplications of a fixed
length, the first family can correct any number of errors while the second
corrects a bounded number of errors. We also study codes for correcting tandem
duplications of length up to a given constant $k$, where we are primarily
focused on the cases of $k=2,3$. Finally, we provide a full classification of
the sets of lengths allowed in tandem duplication that result in a unique root
for all sequences.


title: Short Communication on QUIST: A Quick Clustering Algorithm

abstract:
  In this short communication we introduce the quick clustering algorithm
(QUIST), an efficient hierarchical clustering algorithm based on sorting. QUIST
is a poly-logarithmic divisive clustering algorithm that does not assume the
number of clusters, and/or the cluster size to be known ahead of time. It is
also insensitive to the original ordering of the input.


title: Scaling Submodular Maximization via Pruned Submodularity Graphs

abstract:
  We propose a new random pruning method (called "submodular sparsification
(SS)") to reduce the cost of submodular maximization. The pruning is applied
via a "submodularity graph" over the $n$ ground elements, where each directed
edge is associated with a pairwise dependency defined by the submodular
function. In each step, SS prunes a $1-1/\sqrt{c}$ (for $c>1$) fraction of the
nodes using weights on edges computed based on only a small number ($O(\log
n)$) of randomly sampled nodes. The algorithm requires $\log_{\sqrt{c}}n$ steps
with a small and highly parallelizable per-step computation. An accuracy-speed
tradeoff parameter $c$, set as $c = 8$, leads to a fast shrink rate
$\sqrt{2}/4$ and small iteration complexity $\log_{2\sqrt{2}}n$. Analysis shows
that w.h.p., the greedy algorithm on the pruned set of size $O(\log^2 n)$ can
achieve a guarantee similar to that of processing the original dataset. In news
and video summarization tasks, SS is able to substantially reduce both
computational costs and memory usage, while maintaining (or even slightly
exceeding) the quality of the original (and much more costly) greedy algorithm.


title: Scalable and Passive Wireless Network Clock Synchronization

abstract:
  Clock synchronization is ubiquitous in wireless systems for communication,
sensing and control. In this paper we design a scalable system in which an
indefinite number of passively receiving wireless units can synchronize to a
single master clock at the level of discrete clock ticks. Accurate
synchronization requires an estimate of the node positions. If such information
is available the framework developed here takes position uncertainties into
account. In the absence of such information we propose a mechanism which
enables simultaneous synchronization and positioning. Furthermore we derive the
Cramer-Rao bounds for the system which show that it enables synchronization
accuracy at sub-nanosecond levels. Finally, we develop and evaluate an online
estimation method which is statistically efficient.


title:
How to advance general game playing artificial intelligence by player
  modelling

abstract:
  General game playing artificial intelligence has recently seen important
advances due to the various techniques known as 'deep learning'. However the
advances conceal equally important limitations in their reliance on: massive
data sets; fortuitously constructed problems; and absence of any human-level
complexity, including other human opponents. On the other hand, deep learning
systems which do beat human champions, such as in Go, do not generalise well.
The power of deep learning simultaneously exposes its weakness. Given that deep
learning is mostly clever reconfigurations of well-established methods, moving
beyond the state of art calls for forward-thinking visionary solutions, not
just more of the same. I present the argument that general game playing
artificial intelligence will require a generalised player model. This is
because games are inherently human artefacts which therefore, as a class of
problems, contain cases which require a human-style problem solving approach. I
relate this argument to the performance of state of art general game playing
agents. I then describe a concept for a formal category theoretic basis to a
generalised player model. This formal model approach integrates my existing
'Behavlets' method for psychologically-derived player modelling:
  Cowley, B., Charles, D. (2016). Behavlets: a Method for Practical Player
Modelling using Psychology-Based Player Traits and Domain Specific Features.
User Modeling and User-Adapted Interaction, 26(2), 257-306.


title:
New Gapless COS G140L Mode Proposed for Background-Limited Far-UV
  Observations

abstract:
  Here we describe the observation and calibration procedure for a new G140L
observing mode for the Cosmic Origins Spectrograph (COS) aboard the Hubble
Space Telescope (HST). This mode, CENWAV = 800, is designed to move the far-UV
band fully onto the Segment A detector, allowing for more e cient ob- servation
and analysis by simplifying calibration management between the two channels,
and reducing the astigmatism in this wavelength region. We also de- scribe some
of the areas of scientific interest for which this new mode will be especially
suited.


title: Single Molecule Data Analysis: An Introduction

abstract:
  We review methods of data analysis for biophysical data with a special
emphasis on single molecule applications. Our review is intended for anyone,
from student to established researcher. For someone just getting started, we
focus on exposing the logic, strength and limitations of each method and cite,
as appropriate, the relevant literature for implementation details. We review
traditional frequentist and Bayesian parametric approaches to data analysis and
subsequently extend our discussion to recent non-parametric and information
theoretic methods.


title:
Multiple short-lived stellar prominences on O stars: The O6.5I(n)fp star
  lambda Cephei

abstract:
  Most O and many B stars show unexplained cyclical variability in their
spectral lines, i.e. modulation on the rotational timescale, but not strictly
periodic. The variability occurs in the so-called discrete absorption
components (DACs) that accelerate through the UV-wind line profiles and also in
many optical lines. For such OB stars no dipolar magnetic fields have been
detected with upper limits of ~300G. We investigate whether multiple magnetic
loops on the surface rather than non-radial pulsations or a dipolar magnetic
field can explain the observed cyclical UV and optical spectral line
variability. We present time-resolved, high-resolution optical spectroscopy of
the O6.5I(n)fp star lambda Cep. We apply a simplified phenomenological model in
which multiple spherical blobs attached to the surface represent magnetic-loop
structures, which we call stellar prominences, by analogy with solar
prominences. We compare the calculated line profiles as a function of
rotational phase, adopting a rotation period of 4.1d, with observed relative
changes in subsequent quotient spectra. We identify many periodicities in
spectral lines, almost none of which is stable over timescales from months to
years. We show that the relative changes in various optical absorption and
emission lines are often very similar. Our proposed model applied to the HeII
4686 line can typically be fitted with 2-5 equatorial blobs with lifetimes
between ~1 and 24h. Given the irregular timescales involved, we propose that
the azimuthal distribution of DACs correspond to the locations of stellar
prominences attached to the surface. This could explain the observed
variability of optical and UV lines, and put constraints on the strength and
lifetime of these structures, which can be compared with recent theoretical
predictions, in which bright magnetic surface spots are formed by the action of
the subsurface convection zone.


title: New model for datasets citation and extraction reproducibility in VAMDC

abstract:
  In this paper we present a new paradigm for the identification of datasets
extracted from the Virtual Atomic and Molecular Data Centre (VAMDC) e-science
infrastructure. Such identification includes information on the origin and
version of the datasets, references associated to individual data in the
datasets, as well as timestamps linked to the extraction procedure. This
paradigm is described through the modifications of the language used to
exchange data within the VAMDC and through the services that will implement
those modifications. This new paradigm should enforce traceability of datasets,
favour reproducibility of datasets extraction, and facilitate the systematic
citation of the authors having originally measured and/or calculated the
extracted atomic and molecular data.


title:
Bridging thermal and electrical transport in dielectric nanostructure
  based polar colloids

abstract:
  Heat and charge transport characteristics of nanocolloids have been bridged
from fundamental analysis. The relationship between the two transport phenomena
in dielectric nanostructure based polar colloids has been quantitatively
presented. An extensional intuitive analogy to the Wiedemann Franz law has been
drawn. Derived from the fact that mobile electrons transport both heat and
charge within metallic crystal structure, the analogy can be extended to
nanocolloids, wherein the dispersed population act as the major transporter.
The analogy allows modeling the relationship between the two phenomena and
sheds more insight and conclusive evidence that nanoparticle traversal within
the fluid domain is the main source of augmented transport phenomena exhibit by
nanocolloids. Important factors such as the thermal and dielectric responses of
the nanocolloid can be quantified and bridged through the semi analytical
formalism. The theoretical analysis has been validated against experimental
data and variant scientific literature and good accuracy has been observed.


title:
State-of-the-art of beyond mean field theories with nuclear density
  functionals

abstract:
  We present an overview of beyond mean field theories (BMFT) based on the
generator coordinate method (GCM) and the recovery of symmetries used in
nuclear physics with effective forces. After a reminder of the
Hartree-Fock-Bogoliubov (HFB) theory a discussion of the shortcomings of any
mean field approximation (MFA) is presented. The recovery of the symmetries
spontaneously broken in the HFB approach, in particular the angular momentum,
is necessary, among others, to describe excited states and transitions.
Particle number projection is needed to guarantee the right number of protons
and neutrons. Furthermore a projection before the variation prevents the
pairing collapse in the weak pairing regime. The lack of fluctuations around
the average values of the MFA is a shortcoming of this approach. To build in
correlations in BMFT one selects the relevant degrees of freedom: quadrupole,
octupole and the pairing vibrations as well as the single particle ones. In the
GCM the operators representing these degrees of freedom are used as coordinates
to generate a collective subspace. The highly correlated GCM wave function is
finally written as a linear combination of a projected basis of this space. The
variation of the coefficients of the linear combination leads to the
Hill-Wheeler equation. We discuss the classical beta and gamma vibrations by
considering the quadrupole operators as coordinates. We present pairing
fluctuations by considering the pairing gaps as generator coordinates. Lastly
the explicit consideration of the time reversal symmetry breaking in the HFB
wave function by the cranking procedure allows the alignment of nucleon pairs
opening a new dimension in the BMFT calculations. Abundant calculations with
the Gogny force illustrate the state-of-the-art of BMFTs with density
functionals. We conclude with a thorough discussion on the potential poles of
the theory.


title:
Extension, Torque and Supercoiling in Single, Stretched and Twisted DNA
  Molecules

abstract:
  We reinvestigate the model originally studied by Neukirch and Marko that
describes the extension, torque and supercoiling in single, stretched and
twisted DNA molecules, which consists of a mixture of extended and supercoiled
state, using now a more accurate form of the free energy for the untwisted but
stretched DNA. The original model uses an approximate form of this free energy
and the agreement with experiment is only qualitative. We find that this more
accurate free energy significantly improves the results, bring them into
quantitative agreement with experiment, throughout the entire force regime.
This is rather surprising, considering that the theory is completely
parameter-free.


title:
Bounded normal generation for projective unitary groups of certain
  infinite operator algebras

abstract:
  We study the question how quickly products of a fixed conjugacy class cover
the entire group in the projective unitary group of the connected component of
the identity of the Calkin algebra, as well as the projective unitary group of
a factor von Neumann algebra of type III. Our result is that the number of
factors that are needed is as small as permitted by the (essential) operator
norm - in analogy to a result of Liebeck-Shalev for non-abelian finite simple
groups and analogous results for unitary groups of II_1-factors.


title:
The binary primes sequence for computational hardening of pseudorandom
  sequences

abstract:
  This paper proposes the use of the binary primes sequence to strengthen
pseudorandom (PN) decimal sequences for cryptography applications. The binary
primes sequence is added to the PN decimal sequence (where one can choose from
many arbitrary shift values) and it is shown that the sum sequence has improved
autocorrelation properties besides being computationally hard. Also, an
analysis on the computational complexity is performed and it is shown that the
complexity for the eavesdropper is of exponential complexity and therefore, the
proposed method is an attractive procedure for cryptographic applications.


title:
Temporal Topic Modeling to Assess Associations between News Trends and
  Infectious Disease Outbreaks

abstract:
  In retrospective assessments, internet news reports have been shown to
capture early reports of unknown infectious disease transmission prior to
official laboratory confirmation. In general, media interest and reporting
peaks and wanes during the course of an outbreak. In this study, we quantify
the extent to which media interest during infectious disease outbreaks is
indicative of trends of reported incidence. We introduce an approach that uses
supervised temporal topic models to transform large corpora of news articles
into temporal topic trends. The key advantages of this approach include,
applicability to a wide range of diseases, and ability to capture disease
dynamics - including seasonality, abrupt peaks and troughs. We evaluated the
method using data from multiple infectious disease outbreaks reported in the
United States of America (U.S.), China and India. We noted that temporal topic
trends extracted from disease-related news reports successfully captured the
dynamics of multiple outbreaks such as whooping cough in U.S. (2012), dengue
outbreaks in India (2013) and China (2014). Our observations also suggest that
efficient modeling of temporal topic trends using time-series regression
techniques can estimate disease case counts with increased precision before
official reports by health organizations.


title:
Spectral Singularities in the TE and TM modes of a PT-Symmetric Slab
  System: Optimal conditions for realizing a CPA-Laser

abstract:
  Among the interesting outcomes of the study of the physical applications of
spectral singularities in PT-symmetric optical systems is the discovery of
CPA-lasers. These are devices that act both as a threshold laser and a coherent
perfect absorber (CPA) for the same values of their physical parameters. Unlike
a homogeneous slab that is made to act as a CPA, a slab CPA-laser would absorb
the incident waves coming from the left and right of the device provided that
they have appropriate intensity and phase contrasts. We provide a comprehensive
study of one of the simplest experimentally accessible examples of a CPA-laser,
namely a PT-symmetric optical slab system consisting of a balanced pair of
adjacent or separated gain and loss components. In particular, we give a closed
form expression describing the spectral singularities of the system which
correspond to its CPA-laser configurations. We determine the intensity and
phase contrasts for the TE and TM waves that are emitted (absorbed) whenever
the slab acts as a laser (CPA). We also investigate the behavior of the
time-averaged energy density and Poynting vector for these waves. This is
necessary for determining the optimal values of the physical parameters of the
system that make it act as a CPA-laser. These turn out to correspond to
situations where the separation distance $s$ between the gain and loss layers
is an odd multiple of a characteristic length scale $s_0$. A curious by-product
of our study is that, except for the cases where $s$ is an even integer
multiple of $s_0$, there is a critical angle of polarization beyond which the
energy of the waves emitted from the lossy layer can be larger than the energy
of those emitted from the gain layer.


title:
Nonclassical spectral asymptotics and Dixmier traces: From circles to
  contact manifolds

abstract:
  We consider the spectral behavior and noncommutative geometry of commutators
$[P,f]$, where $P$ is an operator of order $0$ with geometric origin and $f$ a
multiplication operator by a function. When $f$ is H\"{o}lder continuous, the
spectral asymptotics is governed by singularities. We study precise spectral
asymptotics through the computation of Dixmier traces; such computations have
only been considered in less singular settings. Even though a Weyl law fails
for these operators, and no pseudo-differential calculus is available,
variations of Connes' residue trace theorem and related integral formulas
continue to hold. On the circle, a large class of non-measurable Hankel
operators is obtained from H\"older continuous functions $f$, displaying a wide
range of nonclassical spectral asymptotics beyond the Weyl law. The results
extend from Riemannian manifolds to contact manifolds and noncommutative tori.


title: On a Possible Similarity between Gene and Semantic Networks

abstract:
  In several domains such as linguistics, molecular biology or social sciences,
holistic effects are hardly well-defined by modeling with single units, but
more and more studies tend to understand macro structures with the help of
meaningful and useful associations in fields such as social networks, systems
biology or semantic web. A stochastic multi-agent system offers both accurate
theoretical framework and operational computing implementations to model
large-scale associations, their dynamics and patterns extraction. We show that
clustering around a target object in a set of associations of object prove some
similarity in specific data and two case studies about gene-gene and term-term
relationships leading to an idea of a common organizing principle of cognition
with random and deterministic effects.


title:
Magnetic field strength in an intermediate-velocity ionized filament in
  the First Galactic Quadrant

abstract:
  We investigate the magnetic field in an intermediate-velocity filament for
which the H$\alpha$ intensity in the WHAM survey correlates with excess Faraday
rotation of extragalactic radio sources over the length of the filament from b
~ 20 degr. to b ~ 55 degr. The density-weighted mean magnetic field is 2.8 +/-
0.8 microgauss, derived from rotation measures and an empirical relation
between H-alpha emission measure and dispersion measure from Berkhuijsen et al.
(2006). In view of the uncertainties in the derived magnetic field strength, we
propose an alternative use of the available data, rotation measure and emission
measure, to derive a lower limit to the Alfven speed, weighted by electron
density n_e^1.5. We find lower limits to the Alfven speed that are comparable
to, or larger than the sound speed in a 10^4 K plasma, and conclude that the
magnetic field is dynamically important. We discuss the role of
intermediate-velocity gas as a locus of Faraday rotation in the interstellar
medium, and propose this lower limit to the Alfven speed may also be applicable
to Faraday rotation by galaxy clusters.


title: Major depression as a complex dynamic system

abstract:
  In this paper, we characterize major depression (MD) as a complex dynamical
system in which symptoms (e.g., insomnia and fatigue) are directly connected to
one another in a network structure. We hypothesize that individuals can be
characterized by their own network with unique architecture and resulting
dynamics. With respect to architecture, we show that individuals vulnerable to
developing MD are those with strong connections between symptoms: e.g., only
one night of poor sleep suffices to make a particular person feel tired. Such
vulnerable networks, when pushed by forces external to the system such as
stress, are more likely to end up in a depressed state; whereas networks with
weaker connections tend to remain in or return to a healthy state. We show this
with a simulation in which we model the probability of a symptom becoming
active as a logistic function of the activity of its neighboring symptoms.
Additionally, we show that this model potentially explains some well-known
empirical phenomena such as spontaneous recovery as well as accommodates
existing theories about the various subtypes of MD. To our knowledge, we offer
the first intra-individual, symptom-based, process model with the potential to
explain the pathogenesis and maintenance of major depression.


title:
Fiber-to-Waveguide and 3D Chip-to-Chip Light Coupling Based on Bent
  Metal-Clad Waveguides

abstract:
  Efficient fiber-to-waveguide light coupling has been a key issue in
integrated photonics for many years. The main challenge lies in the huge mode
mismatch between an optical fiber and a single mode waveguide. Herein, we
present a novel fiber-to-waveguide coupler, named "L-coupler", through which
the light fed from the top of a chip can bend 90{\deg} with low reflection and
is then efficiently coupled into an on-chip Si waveguide within a short
propagation distance (<20{\mu}m). The key element is a bent metal-clad
waveguide with a big matched input port. According to our finite-difference
time-domain (FDTD) simulation, the coupling efficiency is over 80% within a
broad range of working wavelengths in the near-infrared regime for a transverse
electric input Gaussian wave. The coupler is polarization-dependent, with very
low coupling efficiency (6%-9%) for transverse magnetic waves. The coupler can
also be used for three-dimensional (3D) chip-to-chip optical interconnection by
efficiently coupling light into an integrated photonic chip from a
vertical-cavity surface-emitting laser (VCSEL), or Si waveguide on another
chip. The work presented in this Arxiv article has been filed as a patent.
Detailed description of this work may be published in future papers.


title: Monochromatic paths for the integers

abstract:
  Recall that van der Waerden's theorem states that any finite coloring of the
naturals has arbitrarily long monochromatic arithmetic sequences. We explore
questions about the set of differences of those sequences.


title:
On the one loop $\gamma^{(*)}\to q\bar{q}$ impact factor and the
  exclusive diffractive cross sections for the production of two or three jets

abstract:
  We present the calculation of the impact factor for the $\gamma^{(*)}\to
q\bar{q}$ transition with one loop accuracy in arbitrary kinematics. The
calculation was done within Balitsky's high energy operator expansion. Together
with our previous result for the $\gamma^{(*)}\to q\bar{q} g$ Born impact
factor it allows one to derive cross-sections for 2- (one loop) and 3-jet
(Born) difractive electroproduction. We write such cross sections for the 2 and
3 jet exclusive diffractive electroproduction off a proton in terms of hadronic
matrix elements of Wilson lines. For the 2-jet cross section we demonstrate the
cancellation of IR, collinear and rapidity singularities. Our result can be
directly exploited to describe the recently analyzed data on exclusive dijet
production at HERA and used for the study of jet photoproduction in
ultraperipheral proton or nuclear scattering.


title:
Majorana charges, winding numbers and Chern numbers in quantum Ising
  models

abstract:
  Mapping a many-body state on a loop in parameter space is a simple way to
characterize a quantum state. The connections of such a geometrical
representation to the concepts of Chern number and Majorana zero mode are
investigated based on a generalized quantum spin system with short and
long-range interactions. We show that the topological invariants, the Chern
numbers of corresponding Bloch band is equivalent to the winding number in the
auxiliary plane, which can be utilized to characterize the phase diagram. We
introduce the concept of Majorana charge, the magnitude of which is defined by
the distribution of Majorana fermion probability in zero-mode states, and the
sign is defined by the type of Majorana fermion. By direct calculations of the
Majorana modes we analytically and numerically verify that the Majorana charge
is equal to Chern numbers and winding numbers.


title:
Singular oscillatory integrals in equivariant cohomology. Residue
  formulae for basic differential forms on general symplectic manifolds

abstract:
  Let $M$ be a symplectic manifold and $G$ a connected, compact Lie group
acting on $M$ in a Hamiltonian way. In this paper, we study the equivariant
cohomology of $M$ represented by basic differential forms, and relate it to the
cohomology of the Marsden-Weinstein reduced space via certain residue formulae
using resolution of singularities and the stationary phase principle. In case
that $ M $ is a compact, symplectic manifold or the co-tangent bundle of a
$G$-manifold, similar residue formulae were derived by Jeffrey, Kirwan et al.
for general equivariantly closed forms and by Ramacher for basic differential
forms, respectively.


title: Small-time fluctuations for sub-Riemannian diffusion loops

abstract:
  We study the small-time fluctuations for diffusion processes which are
conditioned by their initial and final positions, under the assumptions that
the diffusivity has a sub-Riemannian structure and that the drift vector field
lies in the span of the sub-Riemannian structure. In the case where the
endpoints agree and the generator of the diffusion process is non-elliptic at
that point, the deterministic Malliavin covariance matrix is always degenerate.
We identify, after a suitable rescaling, another limiting Malliavin covariance
matrix which is non-degenerate, and we show that, with the same scaling, the
diffusion Malliavin covariance matrices are uniformly non-degenerate. We
further show that the suitably rescaled fluctuations of the diffusion loop
converge to a limiting diffusion loop, which is equal in law to the loop we
obtain by taking the limiting process of the unconditioned rescaled diffusion
processes and condition it to return to its starting point. The generator of
the unconditioned limiting rescaled diffusion process can be described in terms
of the original generator.


title: Hexagon POPE: effective particles and tree level resummation

abstract:
  We present the resummation of the full Pentagon Operator Product Expansion
series of the hexagon Wilson loop in planar $\mathcal N=4$ SYM at tree level.
We do so by considering the one effective particle states formed by a
fundamental flux tube excitation and an arbitrary number of the so called
"small fermions" which are then integrated out. We present our proposals for
the one effective particle measures at finite coupling. By evaluating these
measures at tree level and summing over all one effective particle states we
reproduce the full 6 point tree level amplitude.


title: Residential income segregation: A behavioral model of the housing market

abstract:
  We represent the functioning of the housing market and study the relation
between income segregation, income inequality and house prices by introducing a
spatial Agent-Based Model (ABM). Differently from traditional models in urban
economics, we explicitly specify the behavior of buyers and sellers and the
price formation mechanism. Buyers who differ by income select among
heterogeneous neighborhoods using a probabilistic model of residential choice;
sellers employ an aspiration level heuristic to set their reservation offer
price; prices are determined through a continuous double auction. We first
provide an approximate analytical solution of the ABM, shedding light on the
structure of the model and on the effect of the parameters. We then simulate
the ABM and find that: (i) a more unequal income distribution lowers the prices
globally, but implies stronger segregation; (ii) a spike of the demand in one
part of the city increases the prices all over the city; (iii) subsidies are
more efficient than taxes in fostering social mixing.


title: How to morph planar graph drawings

abstract:
  Given an $n$-vertex graph and two straight-line planar drawings of the graph
that have the same faces and the same outer face, we show that there is a morph
(i.e., a continuous transformation) between the two drawings that preserves
straight-line planarity and consists of $O(n)$ steps, which we prove is optimal
in the worst case. Each step is a unidirectional linear morph, which means that
every vertex moves at constant speed along a straight line, and the lines are
parallel although the vertex speeds may differ. Thus we provide an efficient
version of Cairns' 1944 proof of the existence of straight-line
planarity-preserving morphs for triangulated graphs, which required an
exponential number of steps.


title: A special case of the two-dimensional Jacobian Conjecture

abstract:
  Let $f: \mathbb{C}[x,y] \to \mathbb{C}[x,y]$ be a $\mathbb{C}$-algebra
endomorphism having an invertible Jacobian. We show that for such $f$, if, in
addition, the group of invertible elements of $\mathbb{C}[f(x),f(y),x][1/v]
\subset \mathbb{C}(x,y)$ is contained in $\mathbb{C}(f(x),f(y))-0$, then $f$ is
an automorphism. Here $v \in \mathbb{C}[f(x),f(y)]-0$ is such that $y = u/v$,
with $u \in \mathbb{C}[f(x),f(y),x]-0$. Keller's theorem (in dimension two)
follows immediately, since Keller's condition
$\mathbb{C}(f(x),f(y))=\mathbb{C}(x,y)$ implies that the group of invertible
elements of $\mathbb{C}[f(x),f(y),x][1/v]$ is contained in $\mathbb{C}(x,y)-0 =
\mathbb{C}(f(x),f(y))-0$.


title: Entanglement Detection with Single Hong-Ou-Mandel Interferometry

abstract:
  Entanglement is not only fundamental for understanding multipartite quantum
systems but also generally useful for quantum information applications. Despite
much effort devoted so far, little is known about minimal resources for
detecting entanglement and also comparisons to tomography which reveals the
full characterization. Here, we show that all entangled states can in general
be detected in an experimental scheme that estimates the fidelity of two pure
quantum states. An experimental proposal is presented with a single
Hong-Ou-Mandel interferometry in which only two detectors are applied
regardless of the dimensions or the number of modes of quantum systems. This
shows measurement settings for entanglement detection are in general
inequivalent to tomography: the number of detectors in quantum tomography
increases with the dimensions and the modes whereas it is not the case in
estimation of fidelity which detects entangled states.


title:
Fuzzy right (left) ideals in hypergroupoids and fuzzy bi-ideals in
  hypersemigroups

abstract:
  We introduce the concepts of fuzzy right and fuzzy left ideals of
hypergroupoids and the concept of a fuzzy bi-ideal of an hypersemigroup and we
show that a fuzzy subset $f$ of an hypergroupoid $H$ is a fuzzy right (resp.
fuzzy left) ideal of $H$ if and only if $f\circ 1\preceq f$ (resp. $1\circ
f\preceq f)$ and for an hypersemigroup $H$, a fuzzy subset $f$ of $H$ is a
bi-ideal of $H$ if and only if $f\circ 1\circ f\preceq f$. These
characterizations are very useful for the investigation. The paper serves as an
example to show the way we pass from fuzzy groupoids (semigroups) to fuzzy
hypergroupoids (hypersemigroups).


title:
Laminar-Turbulent Transition in Raman Fiber Lasers: A First Passage
  Statistics Based Analysis

abstract:
  Loss of coherence with increasing excitation amplitudes and spatial size
modulation is a fundamental problem in designing Raman fiber lasers. While it
is known that ramping up laser pump power increases the amplitude of stochastic
excitations, such higher energy inputs can also lead to a transition from a
linearly stable coherent laminar regime to a non-desirable disordered turbulent
state. This report presents a new statistical methodology, based on first
passage statistics, that classifies lasing regimes in Raman fiber lasers,
thereby leading to a fast and highly accurate identification of a strong
instability leading to a laminar-turbulent phase transition through a
self-consistently defined order parameter. The results have been consistent
across a wide range of pump power values, heralding a breakthrough in the
non-invasive analysis of fiber laser dynamics.


title:
A systematic study of the superconducting critical temperature in two
  and three dimensional tight-binding models: a possible scenario for
  superconducting H$_3$S ?

abstract:
  Ever since BCS theory was first formulated it was recognized that a large
electronic density of states at the Fermi level was beneficial to enhancing
$T_c$. The A15 compounds and the high temperature cuprate materials both have
had an enormous amount of effort devoted to studying the possibility that such
peaks play an important role in the high critical temperatures existing in
these compounds. Here we provide a systematic study of the effect of these
peaks on the superconducting transition temperature for a variety of
tight-binding models of simple structures, both in two and three dimensions. In
three dimensions large enhancements in $T_c$ can occur, due to van Hove
singularities that result in divergences in the density of states. Furthermore,
even in more realistic structures, where the van Hove singularity disappears,
large enhancements in $T_c$ continue due to the presence of `robust' peaks in
the densities of states. Such a peak, recently identified in the bcc structure
of H$_3$S, is likely the result of such a van Hove singularity. In certain
regimes, anomalies in the isotope coefficient are also expected.


title: Supersymmetric Sneutrino-Higgs Inflation

abstract:
  It is shown that in the phenomenologically realistic supersymmetric $B-L$
MSSM theory, a linear combination of the neutral, up Higgs field with the third
family left-and right-handed sneutrinos can play the role of the cosmological
inflaton. Assuming that supersymmetry is softly broken at a mass scale of order
$10^{13}~\mathrm{GeV}$, the potential energy associated with this field allows
for 60 e-foldings of inflation with the cosmological parameters being
consistent with all Planck2015 data. The theory does not require any
non-standard coupling to gravity and the physical fields are all sub-Planckian
during the inflationary epoch. It will be shown that there is a "robust" set of
initial conditions which, in addition to satisfying the Planck data,
simultaneously are consistent with all present LHC phenomenological
requirements.


title:
An optical transmission spectrum of the transiting hot Jupiter in the
  metal-poor WASP-98 planetary system

abstract:
  The WASP-98 planetary system represents a rare case of a hot Jupiter hosted
by a metal-poor main-sequence star. We present a follow-up study of this system
based on multi-band photometry and high-resolution spectroscopy. Two new
transit events of WASP-98b were simultaneously observed in four passbands
(g,r,i,z), using the telescope-defocussing technique, yielding eight
high-precision light curves with point-to-point scatters of less than 1 mmag.
We also collected three spectra of the parent star with a high-resolution
spectrograph, which we used to remeasure its spectral characteristics, in
particular its metallicity. We found this to be very low, Fe/H]=-0.49, but
larger than was previously reported, [Fe/H]=-0.60. We used these new
photometric and spectroscopic data to refine the orbital and physical
properties of this planetary system, finding that the stellar and planetary
mass measurements are significantly larger than those in the discovery paper.
In addition, the multi-band light curves were used to construct an optical
transmission spectrum of WASP-98b and probe the characteristics of its
atmosphere at the terminator. We measured a lower radius at z compared with the
other three passbands. The maximum variation is between the r and z bands, has
a confidence level of roughly 6 sigma and equates to 5.5 pressure scale
heights. We compared this spectrum to theoretical models, investigating several
possible types of atmospheres, including hazy, cloudy, cloud-free, and clear
atmospheres with titanium and vanadium oxide opacities. We could not find a
good fit to the observations, except in the extreme case of a clear atmosphere
with TiO and VO opacities, in which the condensation of Ti and V was
suppressed. As this case is unrealistic, our results suggest the presence of an
additional optical-absorbing species in the atmosphere of WASP-98b, of unknown
chemical nature.


title: Spherical Cows in Dark Matter Indirect Detection

abstract:
  Dark matter (DM) halos have long been known to be triaxial, but in studies of
possible annihilation and decay signals they are often treated as approximately
spherical. In this work, we examine the asymmetry of potential indirect
detection signals of DM annihilation and decay, exploiting the large statistics
of the hydrodynamic simulation Illustris. We carefully investigate the effects
of the baryons on the sphericity of annihilation and decay signals for both the
case where the observer is at 8.5 kpc from the center of the halo (exemplified
in the case of Milky Way-like halos), and for an observer situated well outside
the halo. In the case of Galactic signals, we find that both annihilation and
decay signals are expected to be quite symmetric, with axis ratios very
different from 1 occurring rarely. In the case of extragalactic signals, while
decay signals are still preferentially spherical, the axis ratio for
annihilation signals has a much flatter distribution, with elongated profiles
appearing frequently. Many of these elongated profiles are due to large
subhalos and/or recent mergers. Comparing to gamma-ray emission from the Milky
Way and X-ray maps of clusters, we find that the gamma-ray background appears
less spherical/more elongated than the expected DM signal from the large
majority of halos, and the Galactic gamma ray excess appears very spherical,
while the X- ray data would be difficult to distinguish from a DM signal by
elongation/sphericity measurements alone.


title:
Spectroscopic Measurements of the Far-Ultraviolet Dust Attenuation Curve
  at z~3

abstract:
  We present the first measurements of the shape of the far-ultraviolet
(far-UV; lambda=950-1500 A) dust attenuation curve at high redshift (z~3). Our
analysis employs rest-frame UV spectra of 933 galaxies at z~3, 121 of which
have very deep spectroscopic observations (>7 hrs) at lambda=850-1300 A, with
the Low Resolution Imaging Spectrograph on the Keck Telescope. By using an
iterative approach in which we calculate the ratios of composite spectra in
different bins of continuum color excess, E(B-V), we derive a dust curve that
implies a lower attenuation in the far-UV for a given E(B-V) than those
obtained with standard attenuation curves. We demonstrate that the UV composite
spectra of z~3 galaxies can be modeled well by assuming our new attenuation
curve, a high covering fraction of HI, and absorption from the Lyman-Werner
bands of H2 with a small (<20%) covering fraction. The low covering fraction of
H2 relative to that of the HI and dust suggests that most of the dust in the
ISM of typical galaxies at z~3 is unrelated to the catalysis of H2, and is
associated with other phases of the ISM (i.e., the ionized and neutral gas).
The far-UV dust curve implies a factor of ~2 lower dust attenuation of Lyman
continuum (ionizing) photons relative to those inferred from the most commonly
assumed attenuation curves for L* galaxies at z~3. Our results may be utilized
to assess the degree to which ionizing photons are attenuated in HII regions
or, more generally, in the ionized or low column density (N(HI)<10^17.2 cm^-2)
neutral ISM of high-redshift galaxies.


title: Axion field and the quark nugget's formation at the QCD phase transition

abstract:
  We study a testable dark matter (DM) model outside of the standard WIMP
paradigm in which the observed ratio $\Omega_{\rm dark} \simeq \Omega_{\rm
visible}$ for visible and dark matter densities finds its natural explanation
as a result of their common QCD origin when both types of matter (DM and
visible) are formed at the QCD phase transition and both are proportional to
$\Lambda_{\rm QCD}$. Instead of conventional "baryogenesis" mechanism we
advocate a paradigm when the "baryogenesis" is actually a charge separation
process which always occur in the presence of the $\cal{CP}$ odd axion field
$a(x)$. In this scenario the global baryon number of the Universe remains zero,
while the unobserved anti-baryon charge is hidden in form of heavy nuggets,
similar to Witten's strangelets and compromise the DM of the Universe. We argue
that the nuggets will be inevitably produced during the QCD phase transition as
a result of Kibble-Zurek mechanism on formation of the topological defects
during a phase transition. Relevant topological defects in our scenario are the
closed bubbles made of the $N_{\rm DW}=1$ axion domain walls. These bubbles, in
general, accrete the baryon (or anti baryon) charge, which eventually result in
formation of the nuggets and anti-nuggets carrying a huge baryon (anti-baryon)
charge. The main consequence of the model, $\Omega_{\rm dark} \approx
\Omega_{\rm visible}$ is insensitive to the axion mass which may assume any
value within the observationally allowed window $10^{-6} {\rm eV} \lesssim m_a
\lesssim 10^{-3}{\rm eV}$. We also estimate the baryon to entropy ratio
$\eta\equiv {n_B}/{n_{\gamma}}\sim 10^{-10}$ within this scenario. Finally, we
comment on implications of these results to the axion search experiments,
including microwave cavity and the Orpheus experiments.


title: Toroidal Horizons in Binary Black Hole Mergers

abstract:
  We find the first binary black hole event horizon with a toroidal topology.
It had been predicted that generically the event horizons of merging black
holes should briefly have a toroidal topology, but such a phase has never been
seen prior to this work. In all previous binary black hole simulations, in the
coordinate slicing used to evolve the black holes, the topology of the event
horizon transitions directly from two spheres during the inspiral to a single
sphere as the black holes merge. We present a coordinate transformation to a
foliation of spacelike hypersurfaces that "cut a hole" through the event
horizon surface, resulting in a toroidal event horizon. A torus could
potentially provide a mechanism for violating topological censorship. However,
these toroidal event horizons satisfy topological censorship by construction,
because we can always trivially apply the inverse coordinate transformation to
remove the topological feature.


title: A Parallel Adaptive Event Horizon Finder for Numerical Relativity

abstract:
  With Advanced LIGO detecting the gravitational waves emitted from a pair of
merging black holes in late 2015, we have a new perspective into the strong
field regime of binary black hole systems. Event horizons are the defining
features of such black hole spacetimes. We introduce a new code for locating
event horizons in numerical simulations based on a Delaunay triangulation on a
topological sphere. The code can automatically refine arbitrary regions of the
event horizon surface to find and explore features such as the hole in a
toroidal event horizon, as discussed in our companion paper. We also
investigate various ways of integrating the geodesic equation and find
evolution equations that can be integrated efficiently with high accuracy.


title:
On the origin of the soft photons of the high synchrotron peaked blazar
  : PKS 1424+240

abstract:
  PKS 1424+240 is a distant very high energy gamma-ray BL Lac object with
redshift $z=0.601$. It was found that pure synchrotron self-Compton (SSC)
process normally need extreme input parameters (e.g., very low magnetic field
intensity and extraordinarily large Doppler factor) to explain its
multi-wavelength spectral energy distributions (SEDs). To avoid the extreme
model parameters, different models have been proposed (e.g., two-zone SSC model
or lepto-hadronic model). In this work, we employ the traditional one-zone
leptonic model after including a weak external Compton component to re-explore
the simultaneous multi-wavelength SEDs of PKS 1424+240 in both high (2009) and
low (2013) states. We find that the input parameters of magnetic field and
Doppler factor are roughly consistent with those of other BL Lacs if a weak
external photon field from either broad line region (BLR) or the dust torus.
However, the required energy density of seed photons from BLR or torus is about
3 orders of magnitude less than that constrained in luminous quasars (e.g.,
flat-spectrum radio quasars, FSRQs). This result suggests that the BLR/torus in
BL Lacs is much weaker than that of luminous FSRQs (but not fully disappear),
and the inverse-Compton of external photons from BLR/torus may still play a
role even in high synchrotron peaked blazars.


title:
The clustering of galaxies in the SDSS-III Baryon Oscillation
  Spectroscopic Survey: RSD measurement from the power spectrum and bispectrum
  of the DR12 BOSS galaxies

abstract:
  We measure and analyse the bispectrum of the final, Data Release 12, galaxy
sample provided by the Baryon Oscillation Spectroscopic Survey, splitting by
selection algorithm into LOWZ and CMASS galaxies. The LOWZ sample contains
361\,762 galaxies with an effective redshift of $z_{\rm LOWZ}=0.32$, and the
CMASS sample 777\,202 galaxies with an effective redshift of $z_{\rm
CMASS}=0.57$. Combining the power spectrum, measured relative to the
line-of-sight, with the spherically averaged bispectrum, we are able to
constrain the product of the growth of structure parameter, $f$, and the
amplitude of dark matter density fluctuations, $\sigma_8$, along with the
geometric Alcock-Paczynski parameters, the product of the Hubble constant and
the comoving sound horizon at the baryon drag epoch, $H(z)r_s(z_d)$, and the
angular distance parameter divided by the sound horizon, $D_A(z)/r_s(z_d)$.
After combining pre-reconstruction RSD analyses of the power spectrum monopole,
quadrupole and bispectrum monopole; with post-reconstruction analysis of the
BAO power spectrum monopole and quadrupole, we find $f(z_{\rm
LOWZ})\sigma_8(z_{\rm LOWZ})=0.427\pm 0.056$, $D_A(z_{\rm LOWZ})/r_s(z_d)=6.60
\pm 0.13$, $H(z_{\rm LOWZ})r_s(z_d)=(11.55\pm 0.38)10^3\,{\rm kms}^{-1}$ for
the LOWZ sample, and $f(z_{\rm CMASS})\sigma_8(z_{\rm CMASS})=0.426\pm 0.029$,
$D_A(z_{\rm CMASS})/r_s(z_d)=9.39 \pm 0.10$, $H(z_{\rm
CMASS})r_s(z_d)=(14.02\pm 0.22)10^3\,{\rm kms}^{-1}$ for the CMASS sample. We
find general agreement with previous BOSS DR11 and DR12 measurements. Combining
our dataset with {\it Planck15} we perform a null test of General Relativity
(GR) through the $\gamma$-parametrisation finding
$\gamma=0.733^{+0.068}_{-0.069}$, which is $\sim2.7\sigma$ away from the GR
predictions.


title:
Dynamical mass and multiplicity constraints on co-orbital bodies around
  stars

abstract:
  Objects transiting near or within the disruption radius of both main sequence
(e.g. KOI 1843) and white dwarf (WD 1145+017) stars are now known. Upon
fragmentation or disintegration, these planets or asteroids may produce
co-orbital configurations of nearly equal-mass objects. However, as evidenced
by the co-orbital objects detected by transit photometry in the WD 1145+017
system, these bodies are largely unconstrained in size, mass, and total number
(multiplicity). Motivated by potential future similar discoveries, we perform
N-body simulations to demonstrate if and how debris masses and multiplicity may
be bounded due to second-to-minute deviations and the resulting accumulated
phase shifts in the osculating orbital period amongst multiple co-orbital equal
point masses. We establish robust lower and upper mass bounds as a function of
orbital period deviation, but find the constraints on multiplicity to be weak.
We also quantify the fuzzy instability boundary, and show that mutual
collisions occur in less than 5%, 10% and 20% of our simulations for masses of
10^{21}, 10^{22} and 10^{23} kg. Our results may provide useful initial rough
constraints on other stellar systems with multiple co-orbital bodies.


title:
Are we witnessing the epoch of reionisation at $z=7.1$ from the spectrum
  of J1120+0641?

abstract:
  We quantify the presence of Ly\alpha\ damping wing absorption from a
partially-neutral intergalactic medium (IGM) in the spectrum of the $z=7.08$
QSO, ULASJ1120+0641. Using a Bayesian framework, we simultaneously account for
uncertainties in: (i) the intrinsic QSO emission spectrum; and (ii) the
distribution of cosmic HI patches during the epoch of reionisation (EoR). For
(i) we use a new intrinsic Ly\alpha\ emission line reconstruction method (Greig
et al.), sampling a covariance matrix of emission line properties built from a
large database of moderate-$z$ QSOs. For (ii), we use the Evolution of 21-cm
Structure (EOS; Mesinger et al.) simulations, which span a range of
physically-motivated EoR models. We find strong evidence for the presence of
damping wing absorption redward of Ly\alpha\ (where there is no contamination
from the Ly\alpha\ forest). Our analysis implies that the EoR is not yet
complete by $z=7.1$, with the volume-weighted IGM neutral fraction constrained
to $\bar{x}_{\rm H\,{\scriptsize I}} = 0.40\substack{+0.21 -0.19}$ at $1\sigma$
($\bar{x}_{\rm H\,{\scriptsize I}} = 0.40\substack{+0.41 -0.32}$ at $2\sigma$).
This result is insensitive to the EoR morphology. Our detection of significant
neutral HI in the IGM at $z=7.1$ is consistent with the latest Planck 2016
measurements of the CMB Thompson scattering optical depth (Planck Collaboration
XLVII).


title: ALMA Observations of HD141569's Circumstellar Disk

abstract:
  We present ALMA band 7 (345 GHz) continuum and $^{12}$CO(J = 3-2)
observations of the circumstellar disk surrounding HD141569. At an age of about
5 Myr, the disk has a complex morphology that may be best interpreted as a
nascent debris system with gas. Our $870\rm~\mu m$ ALMA continuum observations
resolve a dust disk out to approximately $ 56 ~\rm au$ from the star (assuming
a distance of 116 pc) with $0."38$ resolution and $0.07 ~ \rm mJy~beam^{-1}$
sensitivity. We measure a continuum flux density for this inner material of
$3.8 \pm 0.4 ~ \rm mJy$ (including calibration uncertainties). The
$^{12}$CO(3-2) gas is resolved kinematically and spatially from about 30 to 210
au. The integrated $^{12}$CO(3-2) line flux density is $15.7 \pm 1.6~\rm
Jy~km~s^{-1}$. We estimate the mass of the millimeter debris and $^{12}$CO(3-2)
gas to be $\gtrsim0.04~\rm M_{\oplus}$ and $\sim2\times 10^{-3}~\rm
M_{\oplus}$, respectively. If the millimeter grains are part of a collisional
cascade, then we infer that the inner disk ($<50$ au) has $\sim 160~\rm
M_{\oplus}$ contained within objects less than 50 km in radius, depending on
the planetesimal size distribution and density assumptions. MCMC modeling of
the system reveals a disk morphology with an inclination of $53.4^{\circ}$
centered around a $\rm M=2.39~ M_{\odot}$ host star ($\rm Msin(i)=1.92~
M_{\odot}$). We discuss whether the gas in HD141569's disk may be second
generation. If it is, the system can be used to study the clearing stages of
planet formation.


title: Q1549-C25: A Clean Source of Lyman-Continuum Emission at $z=3.15$

abstract:
  We present observations of Q1549-C25, an ~L* star-forming galaxy at z=3.15
for which Lyman-continuum (LyC) radiation is significantly detected in deep
Keck/LRIS spectroscopy. We find no evidence for contamination from a
lower-redshift interloper close to the line of sight in the high
signal-to-noise spectrum of Q1549-C25. Furthermore, the morphology of Q1549-C25
in V_606, J_125, and H_160 Hubble Space Telescope (HST) imaging reveals that
the object consists of a single, isolated component within 1". In combination,
these data indicate Q1549-C25 as a clean spectroscopic detection of LyC
radiation, only the second such object discovered to date at z~3. We model the
spectral energy distribution (SED) of Q1549-C25, finding evidence for
negligible dust extinction, an age (assuming continuous star formation) of ~1
Gyr, and a stellar mass of M_*=7.9x10^9 M_sun. Although it is not possible to
derive strong constraints on the absolute escape fraction of LyC emission,
f_esc(LyC), from a single object, we use simulations of intergalactic and
circumgalactic absorption to infer f_esc(LyC)>=0.51 at 95% confidence. The
combination of deep Keck/LRIS spectroscopy and HST imaging is required to
assemble a larger sample of objects like Q1549-C25, and obtain robust
constraints on the average f_esc(LyC) at z~3 and beyond.


title:
The charged black-hole bomb: A lower bound on the charge-to-mass ratio
  of the explosive scalar field

abstract:
  The well-known superradiant amplification mechanism allows a charged scalar
field of proper mass $\mu$ and electric charge $q$ to extract the Coulomb
energy of a charged Reissner-Nordstr\"om black hole. The rate of energy
extraction can grow exponentially in time if the system is placed inside a
reflecting cavity which prevents the charged scalar field from escaping to
infinity. This composed black-hole-charged-scalar-field-mirror system is known
as the {\it charged black-hole bomb}. Previous numerical studies of this
composed physical system have shown that, in the linearized regime, the
inequality $q/\mu>1$ provides a necessary condition for the development of the
superradiant instability. In the present paper we use analytical techniques to
study the instability properties of the charged black-hole bomb in the regime
of linearized scalar fields. In particular, we prove that the lower bound
${{q}\over{\mu}}>\sqrt{{{r_{\text{m}}/r_--1}\over{r_{\text{m}}/r_+-1}}}$
provides a necessary condition for the development of the superradiant
instability in this composed physical system (here $r_{\pm}$ are the horizon
radii of the charged Reissner-Nordstr\"om black hole and $r_{\text{m}}$ is the
radius of the confining mirror). This {\it analytically} derived lower bound on
the superradiant instability regime of the composed
black-hole-charged-scalar-field-mirror system is shown to agree with direct
{\it numerical} computations of the instability spectrum.


title: Ab initio materials physics and microscopic electrodynamics of media

abstract:
  We argue that the amazing progress of first-principles materials physics
necessitates a revision of the Standard Approach to electrodynamics of media.
We hence subject this Standard Approach to a thorough critique, which shows
both its inherent conceptual problems and its practical inapplicability to
modern ab initio calculations. We then go on to show that the common practice
in ab initio materials physics has overcome these difficulties by taking a
different, microscopic approach to electrodynamics of media, only superficially
resembling the Standard Approach whose validity is restricted to the
macroscopic domain. As this paradigm shift went largely unnoticed outside and
partly even within the ab initio community, the present article aims at a
systematic development and paradigmatic discussion of this new, microscopic
first-principles approach to electrodynamics of media, for which we propose the
name "Functional Approach".


title: Measurement-Based Linear Optics

abstract:
  A major challenge in optical quantum processing is implementing large, stable
interferometers. Here we propose a virtual, measurement-based interferometer
that is programmed on the fly solely by the choice of homodyne measurement
angles. The effects of finite squeezing are captured as uniform amplitude
damping. We compare our proposal to existing (physical) interferometers and
consider its performance for BosonSampling, which could demonstrate
post-classical computational power in the near future. We prove its efficiency
in time and squeezing (energy) in this setting.


title: Classical topological paramagnetism

abstract:
  Topological phases of matter are one of the hallmarks of quantum condensed
matter physics. One of their striking features is a bulk-boundary
correspondence wherein the topological nature of the bulk manifests itself on
boundaries via exotic massless phases. In classical wave phenomena analogous
effects may arise; however, these cannot be viewed as equilibrium phases of
matter. Here we identify a set of rules under which robust equilibrium
classical topological phenomena exist. We write down simple and analytically
tractable classical lattice models of spins and rotors in two and three
dimensions which, at suitable parameter ranges, are paramagnetic in the bulk
but nonetheless exhibit some unusual long-range or critical order on their
boundaries. We point out the role of simplicial cohomology as a means of
classifying, writing-down, and analyzing such models. This opens a new
experimental route for studying strongly interacting topological phases of
spins.


title:
Type-II surface brightness profiles in edge-on galaxies produced by
  flares

abstract:
  Previous numerical studies had apparently ruled out the possibility that
flares in galaxy discs could give rise to the apparent breaks in their
luminosity profiles when observed edge-on. However the studies have not, until
now, analyzed this hypothesis systematically using realistic models for the
disc, the flare, and the bulge. We revisit this theme by analyzing a series of
models which sample a wide range of observationally based structural parameters
for these three components. We have considered realistic distributions of bulge
to disc ratios, morphological parameters of bulges and discs, vertical scale
heights of discs and their radial gradients defining the flare for different
morphological types and stellar mass bins, based on observations. The surface
brightness profiles for the face-on and edge-on views of each model were
simulated to find out whether the flared disc produces a Type-II break in the
disc profile when observed edge-on, and if so under what conditions. Contrary
to previous claims, we find that discs with realistic flares can produce
significant breaks in discs when observed edge-on. Specifically a flare with
the parameters of that of the Milky Way would produce a significant break of
the disc at a Rbreak of ~8.6 kpc if observed edge-on. Central bulges have no
significant effects on the results. These simulations show that flared discs
can explain the existence of many Type-II breaks observed in edge-on galaxies,
in a range of galaxies with low-to-intermediate break strength values of
-0.25<S<-0.1.


title: Known Pulsars Identified in the GMRT 150 MHz All-Sky Survey

abstract:
  We have used the 150 MHz radio continuum survey (TGSS ADR) from the Giant
Metrewave Radio Telescope (GMRT) to search for phase-averaged emission toward
all well-localized radio pulsars north of -53deg Declination. We detect
emission toward 200 pulsars with high confidence (>=5-sigma) and another 88
pulsars at fainter levels. We show that most of our identifications are likely
from pulsars, except for a small number where the measured flux density is
confused by an associated supernova or pulsar-wind nebula, or a globular
cluster. We investigate the radio properties of the 150 MHz sample and we find
an unusually high number of gamma-ray binary millisecond pulsars with very
steep spectral indices. We also note a discrepancy in the measured flux
densities between GMRT and LOFAR pulsar samples, suggesting that the flux
density scale for the LOFAR pulsar sample may be in error by approximately a
factor two. We carry out a separate search of 30 well-localized gamma-ray,
radio-quiet pulsars in an effort to detect a widening of the radio beam into
the line-of-sight at lower frequencies. No steep spectrum emission was detected
either toward individual pulsars or in a weighted stack of all 30 images.


title: Dynamical dark energy versus $\Lambda=$const. in light of observations

abstract:
  After about two decades of the first observational papers confirming the
accelerated expansion of the universe, we are still facing the question whether
the cause of it is a rigid cosmological constant $\Lambda$-term or a mildly
evolving dynamical dark energy (DDE). While studies focusing mainly on CMB
measurements do not perceive signs of physics beyond the $\Lambda$CDM, in this
work we show that if we take a large string $SNIa+BAO+H(z)+LSS+CMB$ of modern
cosmological observations, in which not only the CMB but also a rich sample of
large scale structure formation data are included, one can extract $\sim
3.3\sigma$ signs of DDE using a simple XCDM parameterization. These signs can
be enhanced up to near $3.8\sigma$ in the context of the running vacuum model
(RVM), in which the vacuum energy density is in interaction with dark matter.
Recently the RVM has been shown to provide an efficient and economical solution
to the $\sigma_8$-tension, which is one of the intriguing phenomenological
problems that has not been possible to solve within the $\Lambda$CDM so far.
This fact contributes to strengthen the possibility that dynamical vacuum
energy, or in general DDE, could be presently favored by the observations.


title: Graph-Guided Banding of the Covariance Matrix

abstract:
  Regularization has become a primary tool for developing reliable estimators
of the covariance matrix in high-dimensional settings. To curb the curse of
dimensionality, numerous methods assume that the population covariance (or
inverse covariance) matrix is sparse, while making no particular structural
assumptions on the desired pattern of sparsity. A highly-related, yet
complementary, literature studies the specific setting in which the measured
variables have a known ordering, in which case a banded population matrix is
often assumed. While the banded approach is conceptually and computationally
easier than asking for "patternless sparsity," it is only applicable in very
specific situations (such as when data are measured over time or
one-dimensional space). This work proposes a generalization of the notion of
bandedness that greatly expands the range of problems in which banded
estimators apply.
  We develop convex regularizers occupying the broad middle ground between the
former approach of "patternless sparsity" and the latter reliance on having a
known ordering. Our framework defines bandedness with respect to a known graph
on the measured variables. Such a graph is available in diverse situations, and
we provide a theoretical, computational, and applied treatment of two new
estimators. An R package, called ggb, implements these new methods.


title:
Quantum dynamical field theory for non-equilibrium phase transitions in
  driven open systems

abstract:
  We develop a quantum dynamical field theory for studying phase transitions in
driven open systems coupled to Markovian noise, where non-linear noise effects
and fluctuations beyond semiclassical approximations influence the critical
behaviour. We systematically compare the diagrammatics, the properties of the
renormalization group flow and the structure of the fixed points, of the novel
quantum dynamical field theory and of its semi-classical counterpart, which is
employed to characterise dynamical criticality in three dimensional
driven-dissipative condensates. As an application, we perform the Keldysh
Functional Renormalization of a one dimensional driven open Bose gas, where a
tailored diffusion Markov noise realises an analog of quantum criticality for
driven-dissipative condensation. We find that the associated non-equilibrium
quantum phase transition does not map into the critical behaviour of its three
dimensional classical driven counterpart.


title:
On Homeomorphism Type of Symmetric Products of Compact Riemann Surfaces
  with Punctures

abstract:
  Let $M^2_{g,k}$ and $M^2_{g',k'}$ be compact Riemann surfaces with punctures
($g,g'\ge 0$ - genuses, $k,k'\ge 1$ - number of punctures). For any Hausdorff
space $X$ the quotient space $\mathrm{Sym}^nX := X^n/S_n$ is the $n$-th
symmetric product of $X, \ n\ge 2$. It is well known, that $\mathrm{Sym}^n
M^2_{g,k}$ is a smooth quasi-projective variety. Open manifolds $\mathrm{Sym}^n
M^2_{g,k}$ and $\mathrm{Sym}^n M^2_{g',k'}$ are homotopy equivalent iff $\
2g+k=2g'+k'$.
  Blagojevi\'{c}-Gruji\'{c}-\v{Z}ivaljevi\'{c} Conjecture (2003). Fix any $n\ge
2$, and two pairs $(g,k)$ and $(g',k')$ with the condition $2g+k=2g'+k'$. If
$g\ne g'$, then open manifolds $\mathrm{Sym}^n M^2_{g,k}$ and $\mathrm{Sym}^n
M^2_{g',k'}$ are not continuously homeomorphic.
  The conjecture was proved in 2003 in the paper by P.Blagojevi\'{c},
V.Gruji\'{c} and R.\v{Z}ivaljevi\'{c} for the case $\mathrm{max}(g,g') \ge
\frac{n}{2}$ (this implies the case $n=2$). As far as the author knows, up to
this moment there were no results if $\mathrm{max}(g,g') < \frac{n}{2}$.
  The aim of this paper is to prove the conjecture in full generality.


title:
Gravitational waves within the magnetar model of superluminous
  supernovae and gamma-ray bursts

abstract:
  The light curve of many supernovae (SNe) and gamma-ray bursts (GRBs) can be
explained by a sustained injection of extra energy from its possible central
engine, a rapidly rotating strongly magnetic neutron star (i.e. magnetar). The
magnetic dipole radiation power that the magnetar supplies comes at the expense
of the star's rotational energy. However, radiation by gravitational waves
(GWs) can be more efficient than magnetic dipole radiation because of its
stronger dependence on neutron star spin rate Omega, i.e. Omega^6 (for a static
'mountain') or Omega^8 (for a r-mode fluid oscillation) versus Omega^4 for
magnetic dipole radiation. Here, we use the magnetic field B and initial spin
period P_0 inferred from SN and GRB observations to obtain simple constraints
on the dimensionless amplitude of the mountain of epsilon < 0.01 and r-mode
oscillation of alpha < 1, the former being similar to that obtained by recent
works. We then include GW emission within the magnetar model. We show that when
epsilon > 10^-4 (B/10^14 G) (P_0/1 ms) or alpha > 0.01 (B/10^14 G) (P_0/1
ms)^2, light curves are strongly affected, with significant decrease in peak
luminosity and increase in time to peak luminosity. Thus the GW effects studied
here are more pronounced for low B and short P_0 but are unlikely to be
important in modelling SN and GRB light curves since the amplitudes needed for
noticeable changes are quite large.


title: The correlation matrix of Higgs rates at the LHC

abstract:
  The imperfect knowledge of the Higgs boson decay rates and cross sections at
the LHC constitutes a critical systematic uncertainty in the study of the Higgs
boson properties. We show that the full covariance matrix between the Higgs
rates can be determined from the most elementary sources of uncertainty by a
direct application of probability theory. We evaluate the error magnitudes and
full correlation matrix on the set of Higgs cross sections and branching ratios
at $\sqrt{s}=7$, $8$, $13$ and $14$ TeV, which are provided in ancillary files.
The impact of this correlation matrix on the global fits is illustrated with
the latest $7$+$8$ TeV Higgs dataset.


title: 2015 Update of the Discoveries of Isotopes

abstract:
  The 2015 update of the discovery of nuclide project is presented. Twenty new
nuclides were observed for the first time in 2015. An overall review of all
previous assignments was made in order to apply the discovery criteria
consistently to all elements. In addition, a list of isotopes published so far
only in conference proceedings or internal reports is included.


title:
The Generation of Gravity-Capillary Solitary Waves by a Pressure Source
  Moving at a Trans-critical Speed

abstract:
  The unsteady response of a water free surface to a localized pressure source
moving at constant speed $U$ in the range $0.95c_\mathrm{min} \lesssim U \leq
1.02 c_\mathrm{min}$, where $c_\mathrm{min}$ is the minimum phase speed of
linear gravity-capillary waves in deep water, is investigated through
experiments and numerical simulations. This unsteady response state, which
consists of a V-shaped pattern behind the source and features periodic shedding
of pairs of depressions from the tips of the V, was first observed
qualitatively by Diorio et al. (Phys. Rev. Let., 103, 214502, 2009) and called
state III. In the present investigation, cinematic shadowgraph and
refraction-based techniques are utilized to measure the temporal evolution of
the free surface deformation pattern downstream of the source as it moves along
a towing tank, while numerical simulations of the model equation described by
Cho et al. (J. Fluid Mech., 672, 288-306, 2011) are used to extend the
experimental results over longer times than are possible in the experiments.
From the experiments, it is found that the speed-amplitude characteristics and
the shape of the depressions are nearly the same as those of the freely
propagating gravity-capillary lumps of inviscid potential theory. The decay
rate of the depressions is measured from their height-time characteristics,
which are well fitted by an exponential decay law with an order 1 decay
constant. It is found that the shedding period of the depression pairs
decreases with increasing source strength and speed. As the source speed
approaches $c_\mathrm{min}$, this period tends to about 1~s for all source
magnitudes. At the low-speed boundary of state III, a new response with
unsteady asymmetric shedding of depressions is found. This response is also
predicted by the model equation.