title: Quantum gravitational corrections for spinning particles

abstract:
  We calculate the quantum corrections to the gauge-invariant gravitational
potentials of spinning particles in flat space, induced by loops of both
massive and massless matter fields of various types. While the corrections to
the Newtonian potential induced by massless conformal matter for spinless
particles are well-known, and the same corrections due to massless minimally
coupled scalars [Class. Quant. Grav. 27 (2010) 245008], massless non-conformal
scalars [Phys. Rev. D 87 (2013) 104027] and massive scalars, fermions and
vector bosons [Phys. Rev. D 91 (2015) 064047] have been recently derived,
spinning particles receive additional corrections which are the subject of the
present work. We give both fully analytic results valid for all distances from
the particle, and present numerical results as well as asymptotic expansions.
At large distances from the particle, the corrections due to massive fields are
exponentially suppressed in comparison to the corrections from massless fields,
as one would expect. However, a surprising result of our analysis is that close
to the particle itself, on distances comparable to the Compton wavelength of
the massive fields running in the loops, these corrections can be enhanced with
respect to the massless case.


title: A Comparison of Stellar Elemental Abundance Techniques and Measurements

abstract:
  Stellar elemental abundances are important for understanding the fundamental
properties of a star or stellar group, such as age and evolutionary history, as
well as the composition of an orbiting planet. However, as abundance
measurement techniques have progressed, there has been little standardization
between individual methods and their comparisons. As a result, different
stellar abundance procedures determine measurements that vary beyond quoted
error for the same elements within the same stars (Hinkel et al. 2014). The
purpose of this paper is to better understand the systematic variations between
methods and offer recommendations for producing more accurate results in the
future. We have invited a number of participants from around the world
(Australia, Portugal, Sweden, Switzerland, and USA) to calculate ten element
abundances (C, O, Na, Mg, Al, Si, Fe, Ni, Ba, and Eu) using the same stellar
spectra for four stars (HD361, HD10700, HD121504, HD202206). Each group
produced measurements for each of the stars using: 1) their own autonomous
techniques, 2) standardized stellar parameters, 3) standardized line list, and
4) both standardized parameters and line list. We present the resulting stellar
parameters, absolute abundances, and a metric of data similarity that
quantifies homogeneity of the data. We conclude that standardization of some
kind, particularly stellar parameters, improves the consistency between
methods. However, because results did not converge as more free parameters were
standardized, it is clear there are inherent issues within the techniques that
need to be reconciled. Therefore, we encourage more conversation and
transparency within the community such that stellar abundance determinations
can be reproducible as well as accurate and precise.


title: Table-Top Milliwatt-Class Extreme Ultraviolet High Harmonic Light Source

abstract:
  Extreme ultraviolet (XUV) lasers are essential for the investigation of
fundamental physics. Especially high repetition rate, high photon flux sources
are of major interest for reducing acquisition times and improving signal to
noise ratios in a plethora of applications. Here, an XUV source based on
cascaded frequency conversion is presented, which delivers due to the drastic
better single atom response for short wavelength drivers, an average output
power of (832 +- 204) {\mu}W at 21.7 eV. This is the highest average power
produced by any HHG source in this spectral range surpassing precious
demonstrations by more than a factor of four. Furthermore, a narrow-band
harmonic at 26.6 eV with a relative energy bandwidth of only {\Delta}E/E= 1.8 x
10E-3 has been generated, which is of high interest for high precision
spectroscopy experiments.


title: Density of Spherically-Embedded Stiefel and Grassmann Codes

abstract:
  The density of a code is the fraction of the coding space covered by packing
balls centered around the codewords. This paper investigates the density of
codes in the complex Stiefel and Grassmann manifolds equipped with the chordal
distance. The choice of distance enables the treatment of the manifolds as
subspaces of Euclidean hyperspheres. In this geometry, the densest packings are
not necessarily equivalent to maximum-minimum-distance codes. Computing a
code's density follows from computing: i) the normalized volume of a metric
ball and ii) the kissing radius, the radius of the largest balls one can pack
around the codewords without overlapping. First, the normalized volume of a
metric ball is evaluated by asymptotic approximations. The volume of a small
ball can be well-approximated by the volume of a locally-equivalent tangential
ball. In order to properly normalize this approximation, the precise volumes of
the manifolds induced by their spherical embedding are computed. For larger
balls, a hyperspherical cap approximation is used, which is justified by a
volume comparison theorem showing that the normalized volume of a ball in the
Stiefel or Grassmann manifold is asymptotically equal to the normalized volume
of a ball in its embedding sphere as the dimension grows to infinity. Then,
bounds on the kissing radius are derived alongside corresponding bounds on the
density. Unlike spherical codes or codes in flat spaces, the kissing radius of
Grassmann or Stiefel codes cannot be exactly determined from its minimum
distance. It is nonetheless possible to derive bounds on density as functions
of the minimum distance. Stiefel and Grassmann codes have larger density than
their image spherical codes when dimensions tend to infinity. Finally, the
bounds on density lead to refinements of the standard Hamming bounds for
Stiefel and Grassmann codes.


title: Testing the black hole "no-hair" hypothesis

abstract:
  Black holes in General Relativity are very simple objects. This property,
that goes under the name of "no-hair," has been refined in the last few decades
and admits several versions. The simplicity of black holes makes them ideal
testbeds of fundamental physics and of General Relativity itself. Here we
discuss the no-hair property of black holes, how it can be measured in the
electromagnetic or gravitational window, and what it can possibly tell us about
our universe.

categories: gr-qc astro-ph.HE hep-th physics.class-ph


title: Can stellar activity make a planet seem misaligned?

abstract:
  Several studies have shown that the occultation of stellar active regions by
the transiting planet can generate anomalies in the high-precision transit
light curves, and these anomalies may lead to an inaccurate estimate of the
planetary parameters (e.g., the planet radius). Since the physics and geometry
behind the transit light curve and the Rossiter- McLaughlin effect
(spectroscopic transit) are the same, the Rossiter-McLaughlin observations are
expected to be affected by the occultation of stellar active regions in a
similar way. In this paper we perform a fundamental test on the spin-orbit
angles as derived by Rossiter-McLaughlin measurements, and we examine the
impact of the occultation of stellar active regions by the transiting planet on
the spin-orbit angle estimations. Our results show that the inaccurate
estimation on the spin-orbit angle due to stellar activity can be quite
significant (up to 30 degrees), particularly for the edge-on, aligned, and
small transiting planets. Therefore, our results suggest that the aligned
transiting planets are the ones that can be easily misinterpreted as misaligned
owing to the stellar activity. In other words, the biases introduced by
ignoring stellar activity are unlikely to be the culprit for the highly
misaligned systems.


title:
$C^0$-characterization of symplectic and contact embeddings and
  Lagrangian rigidity

abstract:
  We present a novel $C^0$-characterization of symplectic embeddings and
diffeomorphisms in terms of Lagrangian embeddings. Our approach is based on the
shape invariant, which was discovered by J.-C. Sikorav and Y. Eliashberg,
intersection theory and the displacement energy of Lagrangian submanifolds, and
the fact that non-Lagrangian submanifolds can be displaced immediately. This
characterization gives rise to a new proof of $C^0$-rigidity of symplectic
embeddings and diffeomorphisms. The various manifestations of Lagrangian
rigidity that are used in our arguments come from $J$-holomorphic curve
methods. An advantage of our techniques is that they can be adapted to a
$C^0$-characterization of contact embeddings and diffeomorphisms in terms of
coisotropic (or pre-Lagrangian) embeddings, which in turn leads to a proof of
$C^0$-rigidity of contact embeddings and diffeomorphisms. We give a detailed
treatment of the shape invariants of symplectic and contact manifolds, and
demonstrate that shape is often a natural language in symplectic and contact
topology. We consider homeomorphisms that preserve shape, and propose a
hierarchy of notions of Lagrangian topological submanifold. Moreover, we
discuss shape related necessary and sufficient conditions for symplectic and
contact embeddings, and define a symplectic capacity from the shape.


title:
Variations of cosmic large-scale structure covariance matrices across
  parameter space

abstract:
  The likelihood function for cosmological parameters, given by e.g. weak
lensing shear measurements, depends on contributions to the covariance induced
by the nonlinear evolution of the cosmic web. As nonlinear clustering to date
has only been described by numerical $N$-body simulations in a reliable and
sufficiently precise way, the necessary computational costs for estimating
those covariances at different points in parameter space are tremendous. In
this work we describe the change of the matter covariance and of the weak
lensing covariance matrix as a function of cosmological parameters by
constructing a suitable basis, where we model the contribution to the
covariance from nonlinear structure formation using Eulerian perturbation
theory at third order. We show that our formalism is capable of dealing with
large matrices and reproduces expected degeneracies and scaling with
cosmological parameters in a reliable way. Comparing our analytical results to
numerical simulations we find that the method describes the variation of the
covariance matrix found in the SUNGLASS weak lensing simulation pipeline within
the errors at one-loop and tree-level for the spectrum and the trispectrum,
respectively, for multipoles up to $\ell\leq 1300$. We show that it is possible
to optimize the sampling of parameter space where numerical simulations should
be carried out by minimising interpolation errors and propose a corresponding
method to distribute points in parameter space in an economical way.


title: Magnetic Catalysis in Graphene Effective Field Theory

abstract:
  We report on the first observation of magnetic catalysis at zero temperature
in a fully nonperturbative simulation of the graphene effective field theory.
Using lattice gauge theory, a nonperturbative analysis of the theory of
strongly-interacting, massless, (2+1)-dimensional Dirac fermions in the
presence of an external magnetic field is performed. We show that in the
zero-temperature limit, a nonzero value for the chiral condensate is obtained
which signals the spontaneous breaking of chiral symmetry. This result implies
a nonzero value for the dynamical mass of the Dirac quasiparticle. This in turn
has been posited to account for the quantum-Hall plateaus that are observed at
large magnetic fields.


title: What does a group algebra of a free group know about the group?

abstract:
  We describe solutions to the problem of elementary classification in the
class of group algebras of free groups. We will show that unlike free groups,
two group algebras of free groups over infinite fields are elementarily
equivalent if and only if the groups are isomorphic and the fields are
equivalent in the weak second order logic. We will show that the set of all
free bases of a free group $F$ is 0-definable in the group algebra $K(F)$ when
$K$ is an infinite field, the set of geodesics is definable, and many geometric
properties of $F$ are definable in $K(F)$. Therefore $K(F)$ knows some very
important information about $F$. We will show that similar results hold for
group algebras of limit groups.


title: Epic substructures and primitive positive functions

abstract:
  For $\mathbf{A}\leq\mathbf{B}$ first order structures in a class
$\mathcal{K}$, say that $\mathbf{A}$ is an epic substructure of $\mathbf{B}$ in
$\mathcal{K}$ if for every $\mathbf{C}\in\mathcal{K}$ and all homomorphisms
$g,g^{\prime}:\mathbf{B}\rightarrow\mathbf{C}$, if $g$ and $g'$ agree on $A$,
then $g=g'$. We prove that $\mathbf{A}$ is an epic substructure of $\mathbf{B}$
in a class $\mathcal{K}$ closed under ultraproducts if and only if $A$
generates $\mathbf{B}$ via operations definable in $\mathcal{K}$ with primitive
positive formulas. Applying this result we show that a quasivariety of algebras
$\mathcal{Q}$ with an $n$-ary near-unanimity term has surjective epimorphisms
if and only if $\mathbb{SP}_{n}\mathbb{P}_{u}(\mathcal{Q}_{RSI})$ has
surjective epimorphisms. It follows that if $\mathcal{F}$ is a finite set of
finite algebras with a common near-unanimity term, then it is decidable whether
the (quasi)variety generated by $\mathcal{F}$ has surjective epimorphisms.


title: Privacy-Enhanced Architecture for Occupancy-based HVAC Control

abstract:
  Large-scale sensing and actuation infrastructures have allowed buildings to
achieve significant energy savings; at the same time, these technologies
introduce significant privacy risks that must be addressed. In this paper, we
present a framework for modeling the trade-off between improved control
performance and increased privacy risks due to occupancy sensing. More
specifically, we consider occupancy-based HVAC control as the control objective
and the location traces of individual occupants as the private variables.
Previous studies have shown that individual location information can be
inferred from occupancy measurements. To ensure privacy, we design an
architecture that distorts the occupancy data in order to hide individual
occupant location information while maintaining HVAC performance. Using mutual
information between the individual's location trace and the reported occupancy
measurement as a privacy metric, we are able to optimally design a scheme to
minimize privacy risk subject to a control performance guarantee. We evaluate
our framework using real-world occupancy data: first, we verify that our
privacy metric accurately assesses the adversary's ability to infer private
variables from the distorted sensor measurements; then, we show that control
performance is maintained through simulations of building operations using
these distorted occupancy readings.


title:
Competing Mechanisms between Dislocation and Phase Transformation in
  Plastic Deformation of Single Crystalline Yttria-Stabilized Tetragonal
  Zirconia Nanopillars

abstract:
  Molecular dynamics (MD) is employed to investigate the plastic deformation
mechanisms of single crystalline yttria-stabilized tetragonal zirconia (YSTZ)
nanopillars under uniaxial compression. Simulation results show that the
nanoscale plastic deformation of YSTZ is strongly dependent on the
crystallographic orientation of zirconia nanopillars. For the first time, the
experimental explored tetragonal to monoclinic phase transformation is
reproduced by MD simulations in some particular loading directions. Three
distinct mechanisms of dislocation, phase transformation, and a combination of
dislocation and phase transformation are identified when applying compressive
loading along different directions. The strength of zirconia nanopillars
exhibits a sensitive behavior depending on the failure mechanisms, such that
the dislocation-mediated deformation leads to the lowest strength, while the
phase transformation-dominated deformation results in the highest strength.


title: Searching equillibriums in large transport networks

abstract:
  In this Doctoral Dissertation we propose new variational principles for
traffic assignment problems. So to find equillibrium we have to solve
large-scale convex optimization problem of special (multilevel) type. We
propose different numerical approaches for this problem.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: Cosmological implications of the Fourier space wedges
  of the final sample

abstract:
  We extract cosmological information from the anisotropic power spectrum
measurements from the recently completed Baryon Oscillation Spectroscopic
Survey (BOSS), extending the concept of clustering wedges to Fourier space.
Making use of new FFT-based estimators, we measure the power spectrum
clustering wedges of the BOSS sample by filtering out the information of
Legendre multipoles l > 4. Our modelling of these measurements is based on
novel approaches to describe non-linear evolution, bias, and redshift-space
distortions, which we test using synthetic catalogues based on large-volume
N-body simulations. We are able to include smaller scales than in previous
analyses, resulting in tighter cosmological constraints. Using three
overlapping redshift bins, we measure the angular diameter distance, the Hubble
parameter, and the cosmic growth rate, and explore the cosmological
implications of our full shape clustering measurements in combination with CMB
and SN Ia data. Assuming a {\Lambda}CDM cosmology, we constrain the matter
density to {\Omega}_m = 0.311 -0.010 +0.009 and the Hubble parameter to H_0 =
67.6 -0.6 +0.7 km s^-1 Mpc^-1, at a confidence level (CL) of 68 per cent. We
also allow for non-standard dark energy models and modifications of the growth
rate, finding good agreement with the {\Lambda}CDM paradigm. For example, we
constrain the equation-of-state parameter to w = -1.019 -0.039 +0.048. This
paper is part of a set that analyses the final galaxy clustering dataset from
BOSS. The measurements and likelihoods presented here are combined with others
in Alam et al. 2016 to produce the final cosmological constraints from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: Angular clustering tomography and its cosmological
  implications

abstract:
  We investigate the cosmological implications of studying galaxy clustering
using a tomographic approach applied to the final BOSS DR12 galaxy sample,
including both auto- and cross-correlation functions between redshift shells.
We model the signal of the full shape of the angular correlation function,
$\omega(\theta)$, in redshift bins using state-of-the-art modelling of
non-linearities, bias and redshift-space distortions. We present results on the
redshift evolution of the linear bias of BOSS galaxies, which cannot be
obtained with traditional methods for galaxy-clustering analysis. We also
obtain constraints on cosmological parameters, combining this tomographic
analysis with measurements of the cosmic microwave background (CMB) and type Ia
supernova (SNIa). We explore a number of cosmological models, including the
standard $\Lambda$CDM model and its most interesting extensions, such as
deviations from $w_\rm{DE} = -1$, non-minimal neutrino masses, spatial
curvature and deviations from general relativity using the growth-index
$\gamma$ parametrisation. These results are, in general, comparable to the most
precise present-day constraints on cosmological parameters, and show very good
agreement with the standard model. In particular, combining CMB,
$\omega(\theta)$ and SNIa, we find a value of $w_\rm{DE}$ consistent with $-1$
to a precision better than 5\% when it is assumed to be constant in time, and
better than 6\% when we also allow for a spatially-curved Universe.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: Observational systematics and baryon acoustic
  oscillations in the correlation function

abstract:
  We present baryon acoustic oscillation (BAO) scale measurements determined
from the clustering of 1.2 million massive galaxies with redshifts 0.2 < z <
0.75 distributed over 9300 square degrees, as quantified by their
redshift-space correlation function. In order to facilitate these measurements,
we define, describe, and motivate the selection function for galaxies in the
final data release (DR12) of the SDSS III Baryon Oscillation Spectroscopic
Survey (BOSS). This includes the observational footprint, masks for image
quality and Galactic extinction, and weights to account for density
relationships intrinsic to the imaging and spectroscopic portions of the
survey. We simulate the observed systematic trends in mock galaxy samples and
demonstrate that they impart no bias on baryon acoustic oscillation (BAO) scale
measurements and have a minor impact on the recovered statistical uncertainty.
We measure transverse and radial BAO distance measurements in 0.2 < z < 0.5,
0.5 < z < 0.75, and (overlapping) 0.4 < z < 0.6 redshift bins. In each redshift
bin, we obtain a precision that is 2.7 per cent or better on the radial
distance and 1.6 per cent or better on the transverse distance. The combination
of the redshift bins represents 1.8 per cent precision on the radial distance
and 1.1 per cent precision on the transverse distance. This paper is part of a
set that analyses the final galaxy clustering dataset from BOSS. The
measurements and likelihoods presented here are combined with others in Alam et
al. (2016) to produce the final cosmological constraints from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: combining correlated Gaussian posterior distributions

abstract:
  The cosmological information contained in anisotropic galaxy clustering
measurements can often be compressed into a small number of parameters whose
posterior distribution is well described by a Gaussian. We present a general
methodology to combine these estimates into a single set of consensus
constraints that encode the total information of the individual measurements,
taking into account the full covariance between the different methods. We
illustrate this technique by applying it to combine the results obtained from
different clustering analyses, including measurements of the signature of
baryon acoustic oscillations (BAO) and redshift-space distortions (RSD), based
on a set of mock catalogues of the final SDSS-III Baryon Oscillation
Spectroscopic Survey (BOSS). Our results show that the region of the parameter
space allowed by the consensus constraints is smaller than that of the
individual methods, highlighting the importance of performing multiple analyses
on galaxy surveys even when the measurements are highly correlated. This paper
is part of a set that analyses the final galaxy clustering dataset from BOSS.
The methodology presented here is used in Alam et al. (2016) to produce the
final cosmological constraints from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: cosmological implications of the configuration-space
  clustering wedges

abstract:
  We explore the cosmological implications of anisotropic clustering
measurements in configuration space of the final galaxy samples from Data
Release 12 of the SDSS-III Baryon Oscillation Spectroscopic Survey. We
implement a new detailed modelling of the effects of non-linearities, galaxy
bias and redshift-space distortions that can be used to extract unbiased
cosmological information from our measurements for scales $s \gtrsim
20\,h^{-1}{\rm Mpc}$. We combined the galaxy clustering information from BOSS
with the latest cosmic microwave background (CMB) observations and Type Ia
supernovae samples and found no significant evidence for a deviation from the
$\Lambda$CDM cosmological model. In particular, these data sets can constrain
the dark energy equation of state parameter to $w_{\rm DE}=-0.996\pm0.042$ when
assumed time-independent, the curvature of the Universe to
$\Omega_{k}=-0.0007\pm 0.0030$ and the sum of the neutrino masses to $\sum
m_{\nu} < 0.25\,{\rm eV}$ at 95 per cent CL. We explore the constraints on the
growth rate of cosmic structures assuming $f(z)=\Omega_{\rm m}(z)^\gamma$ and
obtain $\gamma = 0.609\pm 0.079$, in good agreement with the predictions of
general relativity of $\gamma=0.55$. We compress the information of our
clustering measurements into constraints on the parameter combinations $D_{\rm
V}(z)/r_{\rm d}$, $F_{\rm AP}(z)$ and $f\sigma_8(z)$ at the effective redshifts
of $z=0.38$, $0.51$ and $0.61$ with their respective covariance matrices and
find good agreement with the predictions for these parameters obtained from the
best-fitting $\Lambda$CDM model to the CMB data from the Planck satellite. This
paper is part of a set that analyses the final galaxy clustering dataset from
BOSS. The measurements and likelihoods presented here are combined with others
in Alam et al. (2016) to produce the final cosmological constraints from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: On the measurement of growth rate using galaxy
  correlation functions

abstract:
  We present a measurement of the linear growth rate of structure, \textit{f}
from the Sloan Digital Sky Survey III (SDSS III) Baryon Oscillation
Spectroscopic Survey (BOSS) Data Release 12 (DR12) using Convolution Lagrangian
Perturbation Theory (CLPT) with Gaussian Streaming Redshift-Space Distortions
(GSRSD) to model the two point statistics of BOSS galaxies in DR12. The
BOSS-DR12 dataset includes 1,198,006 massive galaxies spread over the redshift
range $0.2 < z < 0.75$. These galaxy samples are categorized in three redshift
bins. Using CLPT-GSRSD in our analysis of the combined sample of the three
redshift bins, we report measurements of $f \sigma_8$ for the three redshift
bins. We find $f \sigma_8 = 0.430 \pm 0.054$ at $z_{\rm eff} = 0.38$, $f
\sigma_8 = 0.452 \pm 0.057$ at $z_{\rm eff} = 0.51$ and $f \sigma_8 = 0.457 \pm
0.052$ at $z_{\rm eff} = 0.61$. Our results are consistent with the predictions
of Planck $\Lambda$CDM-GR. Our constraints on the growth rates of structure in
the Universe at different redshifts serve as a useful probe, which can help
distinguish between a model of the Universe based on dark energy and models
based on modified theories of gravity. This paper is part of a set that
analyses the final galaxy clustering dataset from BOSS. The measurements and
likelihoods presented here are combined with others in Alam et al. 2016 to
produce the final cosmological constraints from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: Baryon Acoustic Oscillations in Fourier-space

abstract:
  We analyse the Baryon Acoustic Oscillation (BAO) signal of the final Baryon
Oscillation Spectroscopic Survey (BOSS) data release (DR12). Our analysis is
performed in Fourier-space, using the power spectrum monopole and quadrupole.
The dataset includes $1\,198\,006$ galaxies over the redshift range $0.2 < z <
0.75$. We divide this dataset into three (overlapping) redshift bins with the
effective redshifts $\zeff = 0.38$, $0.51$ and $0.61$. We demonstrate the
reliability of our analysis pipeline using N-body simulations as well as $\sim
1000$ MultiDark-Patchy mock catalogues, which mimic the BOSS-DR12 target
selection. We apply density field reconstruction to enhance the BAO
signal-to-noise ratio. By including the power spectrum quadrupole we can
separate the line-of-sight and angular modes, which allows us to constrain the
angular diameter distance $D_A(z)$ and the Hubble parameter $H(z)$ separately.
We obtain two independent $1.6\%$ and $1.5\%$ constraints on $D_A(z)$ and
$2.9\%$ and $2.3\%$ constraints on $H(z)$ for the low ($\zeff=0.38$) and high
($\zeff=0.61$) redshift bin, respectively. We obtain two independent $1\%$ and
$0.9\%$ constraints on the angular averaged distance $D_V(z)$, when ignoring
the Alcock-Paczynski effect. The detection significance of the BAO signal is of
the order of $8\sigma$ (post-reconstruction) for each of the three redshift
bins. Our results are in good agreement with the Planck prediction within
$\Lambda$CDM. This paper is part of a set that analyses the final galaxy
clustering dataset from BOSS. The measurements and likelihoods presented here
are combined with others in~\citet{Alam2016} to produce the final cosmological
constraints from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: Anisotropic galaxy clustering in Fourier-space

abstract:
  We investigate the anisotropic clustering of the Baryon Oscillation
Spectroscopic Survey (BOSS) Data Release 12 (DR12) sample, which consists of
$1\,198\,006$ galaxies in the redshift range $0.2 < z < 0.75$ and a sky
coverage of $10\,252\,$deg$^2$. We analyse this dataset in Fourier space, using
the power spectrum multipoles to measure Redshift-Space Distortions (RSD)
simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic
Oscillation (BAO) scale. We include the power spectrum monopole, quadrupole and
hexadecapole in our analysis and compare our measurements with a perturbation
theory based model, while properly accounting for the survey window function.
To evaluate the reliability of our analysis pipeline we participate in a mock
challenge, which resulted in systematic uncertainties significantly smaller
than the statistical uncertainties. While the high-redshift constraint on
$f\sigma_8$ at $z_{\rm eff}=0.61$ indicates a small ($\sim 1.4\sigma$)
deviation from the prediction of the Planck $\Lambda$CDM model, the
low-redshift constraint is in good agreement with Planck $\Lambda$CDM. This
paper is part of a set that analyses the final galaxy clustering dataset from
BOSS. The measurements and likelihoods presented here are combined with others
in~\citet{Alam2016} to produce the final cosmological constraints from BOSS.


title:
The Clustering of Galaxies in the Completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: single-probe measurements from DR12 galaxy clustering
  -- towards an accurate model

abstract:
  We analyse the broad-range shape of the monopole and quadrupole correlation
functions of the BOSS Data Release 12 (DR12) CMASS and LOWZ galaxy sample to
obtain constraints on the Hubble expansion rate $H(z)$, the angular-diameter
distance $D_A(z)$, the normalised growth rate $f(z)\sigma_8(z)$, and the
physical matter density $\Omega_mh^2$. We adopt wide and flat priors on all
model parameters in order to ensure the results are those of a `single-probe'
galaxy clustering analysis. We also marginalise over three nuisance terms that
account for potential observational systematics affecting the measured
monopole. However, such Monte Carlo Markov Chain analysis is computationally
expensive for advanced theoretical models, thus we develop a new methodology to
speed up our analysis. We obtain $\{D_A(z)r_{s,fid}/r_s$Mpc,
$H(z)r_s/r_{s,fid}$kms$^{-1}$Mpc$^{-1}$, $f(z)\sigma_8(z)$, $\Omega_m h^2\}$ =
$\{956\pm28$ , $75.0\pm4.0$ , $0.397 \pm 0.073$, $0.143\pm0.017\}$ at $z=0.32$
and $\{1421\pm23$, $96.7\pm2.7$ , $0.497 \pm 0.058$, $0.137\pm0.015\}$ at
$z=0.59$ where $r_s$ is the comoving sound horizon at the drag epoch and
$r_{s,fid}=147.66$Mpc for the fiducial cosmology in this study. In addition, we
divide the galaxy sample into four redshift bins to increase the sensitivity of
redshift evolution. However, we do not find improvements in terms of
constraining dark energy model parameters. Combining our measurements with
Planck data, we obtain $\Omega_m=0.306\pm0.009$,
$H_0=67.9\pm0.7$kms$^{-1}$Mpc$^{-1}$, and $\sigma_8=0.815\pm0.009$ assuming
$\Lambda$CDM; $\Omega_k=0.000\pm0.003$ assuming oCDM; $w=-1.01\pm0.06$ assuming
$w$CDM; and $w_0=-0.95\pm0.22$ and $w_a=-0.22\pm0.63$ assuming $w_0w_a$CDM. Our
results show no tension with the flat $\Lambda$CDM cosmological paradigm. This
paper is part of a set that analyses the final galaxy clustering dataset from
BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: double-probe measurements from BOSS galaxy clustering
  \& Planck data -- towards an analysis without informative priors

abstract:
  We develop a new methodology called double-probe analysis with the aim of
minimizing informative priors in the estimation of cosmological parameters. We
extract the dark-energy-model-independent cosmological constraints from the
joint data sets of Baryon Oscillation Spectroscopic Survey (BOSS) galaxy sample
and Planck cosmic microwave background (CMB) measurement. We measure the mean
values and covariance matrix of $\{R$, $l_a$, $\Omega_b h^2$, $n_s$,
$log(A_s)$, $\Omega_k$, $H(z)$, $D_A(z)$, $f(z)\sigma_8(z)\}$, which give an
efficient summary of Planck data and 2-point statistics from BOSS galaxy
sample, where $R=\sqrt{\Omega_m H_0^2}\,r(z_*)$, and $l_a=\pi r(z_*)/r_s(z_*)$,
$z_*$ is the redshift at the last scattering surface, and $r(z_*)$ and
$r_s(z_*)$ denote our comoving distance to $z_*$ and sound horizon at $z_*$
respectively. The advantage of this method is that we do not need to put
informative priors on the cosmological parameters that galaxy clustering is not
able to constrain well, i.e. $\Omega_b h^2$ and $n_s$. Using our double-probe
results, we obtain $\Omega_m=0.304\pm0.009$, $H_0=68.2\pm0.7$, and
$\sigma_8=0.806\pm0.014$ assuming $\Lambda$CDM; and $\Omega_k=0.002\pm0.003$
and $w=-1.00\pm0.07$ assuming o$w$CDM. The results show no tension with the
flat $\Lambda$CDM cosmological paradigm. By comparing with the full-likelihood
analyses with fixed dark energy models, we demonstrate that the double-probe
method provides robust cosmological parameter constraints which can be
conveniently used to study dark energy models. We extend our study to measure
the sum of neutrino mass and obtain $\Sigma m_\nu<0.10/0.22$ (68\%/95\%)
assuming $\Lambda$CDM and $\Sigma m_\nu<0.26/0.52$ (68\%/95\%) assuming $w$CDM.
This paper is part of a set that analyses the final galaxy clustering dataset
from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: tomographic BAO analysis of DR12 combined sample in
  Fourier space

abstract:
  We perform a tomographic baryon acoustic oscillations (BAO) analysis using
the monopole, quadrupole and hexadecapole of the redshift-space galaxy power
spectrum measured from the pre-reconstructed combined galaxy sample of the
completed Sloan Digital Sky Survey (SDSS-III) Baryon Oscillation Spectroscopic
Survey (BOSS) Data Release (DR)12 covering the redshift range of $0.20<z<0.75$.
By allowing for overlap between neighbouring redshift slices, we successfully
obtained the isotropic and anisotropic BAO distance measurements within nine
redshift slices to a precision of $1.5\%-3.4\%$ for $D_V/r_d$, $1.8\% -4.2\%$
for $D_A/r_d$ and $3.7\% - 7.5\%$ for $H \ r_d$, depending on effective
redshifts. We provide our BAO measurement of $D_A/r_d$ and $H \ r_d$ with the
full covariance matrix, which can be used for cosmological implications. Our
measurements are consistent with those presented in \citet{Acacia}, in which
the BAO distances are measured at three effective redshifts. We constrain dark
energy parameters using our measurements, and find an improvement of the
Figure-of-Merit of dark energy in general due to the temporal BAO information
resolved. This paper is part of a set that analyses the final galaxy clustering
dataset from BOSS.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: tomographic BAO analysis of DR12 combined sample in
  configuration space

abstract:
  We perform a tomographic baryon acoustic oscillations analysis using the
two-point galaxy correlation function measured from the combined sample of BOSS
DR12, which covers the redshift range of $0.2<z<0.75$. Splitting the sample
into multiple overlapping redshift slices to extract the redshift information
of galaxy clustering, we obtain a measurement of $D_A(z)/r_d$ and $H(z)r_d$ at
nine effective redshifts with the full covariance matrix calibrated using
MultiDark-Patchy mock catalogues. Using the reconstructed galaxy catalogues, we
obtain the precision of $1.3\%-2.2\%$ for $D_A(z)/r_d$ and $2.1\%-6.0\%$ for
$H(z)r_d$. To quantify the gain from the tomographic information, we compare
the constraints on the cosmological parameters using our 9-bin BAO
measurements, the consensus 3-bin BAO and RSD measurements at three effective
redshifts in \citet{Alam2016}, and the non-tomographic (1-bin) BAO measurement
at a single effective redshift. Comparing the 9-bin with 1-bin constraint
result, it can improve the dark energy Figure of Merit by a factor of 1.24 for
the Chevallier-Polarski-Linder parametrisation for equation of state parameter
$w_{\rm DE}$. The errors of $w_0$ and $w_a$ from 9-bin constraints are slightly
improved when compared to the 3-bin constraint result.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample

abstract:
  We present cosmological results from the final galaxy clustering data set of
the Baryon Oscillation Spectroscopic Survey, part of the Sloan Digital Sky
Survey III. Our combined galaxy sample comprises 1.2 million massive galaxies
over an effective area of 9329 deg^2 and volume of 18.7 Gpc^3, divided into
three partially overlapping redshift slices centred at effective redshifts
0.38, 0.51, and 0.61. We measure the angular diameter distance DM and Hubble
parameter H from the baryon acoustic oscillation (BAO) method after applying
reconstruction to reduce non-linear effects on the BAO feature. Using the
anisotropic clustering of the pre-reconstruction density field, we measure the
product DM*H from the Alcock-Paczynski (AP) effect and the growth of structure,
quantified by f{\sigma}8(z), from redshift-space distortions (RSD). We combine
measurements presented in seven companion papers into a set of consensus values
and likelihoods, obtaining constraints that are tighter and more robust than
those from any one method. Combined with Planck 2015 cosmic microwave
background measurements, our distance scale measurements simultaneously imply
curvature {\Omega}_K =0.0003+/-0.0026 and a dark energy equation of state
parameter w = -1.01+/-0.06, in strong affirmation of the spatially flat cold
dark matter model with a cosmological constant ({\Lambda}CDM). Our RSD
measurements of f{\sigma}_8, at 6 per cent precision, are similarly consistent
with this model. When combined with supernova Ia data, we find H0 = 67.3+/-1.0
km/s/Mpc even for our most general dark energy model, in tension with some
direct measurements. Adding extra relativistic species as a degree of freedom
loosens the constraint only slightly, to H0 = 67.8+/-1.2 km/s/Mpc. Assuming
flat {\Lambda}CDM we find {\Omega}_m = 0.310+/-0.005 and H0 = 67.6+/-0.5
km/s/Mpc, and we find a 95% upper limit of 0.16 eV/c^2 on the neutrino mass
sum.


title:
On the proper push-forward of the characteristic cycle of a
  constructible sheaf

abstract:
  We study the compatibility with proper push-forward of the characteristic
cycles of a constructible complex on a smooth variety over a perfect field.


title: Characteristic cycle of the exterior product of constructible sheaves

abstract:
  We show that the characteristic cycle of the exterior product of
constructible complexes is the exterior product of the characteristic cycles of
factors. This implies the compatibility of characteristic cycles with smooth
pull-back which is a first step in the proof of the index formula.


title:
Fine-structure electron-impact excitation of Ne$^{+}$ and Ne$^{2+}$ for
  low temperature astrophysical plasmas

abstract:
  Collision strengths for electron-impact of fine-structure level excitation
within the ground term of Ne$^{+}$ and Ne$^{2+}$ are calculated using the
Breit-Pauli, Intermediate Coupling Frame Transformation, and DARC $R$-matrix
methods. Maxwellian-averaged effective collision strengths and excitation rate
coefficient qij are presented for each. The application of the current
calculations is to very low temperature astrophysical plasmas, thus we examine
the sensitivity of the effective collision strengths down to 10 K. The use of
the various theoretical methods allows us to place estimated uncertainties on
the recommended effective collision strengths. We also investigate the
sensitivity of the collision strengths to the resonance positions and
underlying atomic structure. Good agreement is found with previous R-matrix
calculations at higher temperature.


title: Entanglement of self interacting scalar fields in an expanding spacetime

abstract:
  We evaluate self-interaction effects on the quantum correlations of field
modes of opposite momenta for scalar $\lambda \phi^4$ theory in a
two-dimensional asymptotically flat Robertson-Walker spacetime. Such
correlations are encoded both in the von-Neumann entropy defined through the
reduced density matrix in one of the modes and in the covariance expressed in
terms of the expectation value of the number operators for each mode in the
evolved state. The entanglement between field modes carries information about
the underlying spacetime evolution.


title:
Compact Coding Using Multi-Photon Tolerant Quantum Protocols for Quantum
  Communication

abstract:
  This paper presents a new encryption scheme called Compact Coding that
encodes information in time, phase, and intensity domains, simultaneously.
While these approaches have previously been used one at a time, the proposed
scheme brings to bear for the first time their strengths simultaneously leading
to an increase in the secure information transfer rate. The proposed scheme is
applicable to both optical fibers and free space optics, and can be considered
as an alternative to polarization coding. This paper applies the proposed
compact coding scheme to multi-photon tolerant quantum protocols in order to
produce quantum-level security during information transfer. We present the
structure of the proposed coding scheme in a multi-photon environment and
address its operation.


title: A mathematical model for a gaming community

abstract:
  We consider a large community of individuals who mix strongly and meet in
pairs to bet on a coin toss. We investigate the asset distribution of the
players involved in this zero-sum repeated game. Our main result is that the
asset distribution converges to the exponential distribution, irrespective of
the size of the bet, as long as players can never go bankrupt. Analytical
results suggests that the exponential distribution is a stable fixed point for
this zero-sum repreated game. This is confirmed in numerical experiments.


title:
Nonlinear Stabilization of High-Energy and Ultrashort Pulses in
  Passively Modelocked Lasers with Fast Saturable Absorption

abstract:
  The two most commonly used models for passively modelocked lasers with fast
saturable absorbers are the Haus modelocking equation (HME) and the
cubic-quintic modelocking equation (CQME). The HME corresponds to a special
limit of the CQME in which only a cubic nonlinearity in the fast saturable
absorber is kept in the model. Here, we use singular perturbation theory to
demonstrate that the CQME has a stable high-energy solution for an arbitrarily
small but non-zero quintic contribution to the fast saturable absorber. As a
consequence, we find that the CQME predicts the existence of stable modelocked
pulses when the cubic nonlinearity is orders of magnitude larger than the value
at which the HME predicts that modelocked pulses become unstable. This
intrinsically larger stability range is consistent with experiments. Our
results suggest a possible path to obtain high-energy and ultrashort pulses by
fine tuning the higher-order nonlinear terms in the fast saturable absorber.


title: Secure quantum routing

abstract:
  We show that a quantum network can protect the identity of a sender and
receiver from an external wiretapper. This new quantum communication protocol,
which we call secure quantum routing, requires only single photons routed by
linear optical elements and photon counters, and does not require distributing
entanglement over multiple nodes or active feedforward. We prove that secure
quantum routing protects both the contents of the message and the identity of
the sender and receiver, and creates only a negligible reduction in the network
channel capacity.


title:
Fast Cosine Transform to increase speed-up and efficiency of
  Karhunen-Loeve Transform for lossy image compression

abstract:
  In this work, we present a comparison between two techniques of image
compression. In the first case, the image is divided in blocks which are
collected according to zig-zag scan. In the second one, we apply the Fast
Cosine Transform to the image, and then the transformed image is divided in
blocks which are collected according to zig-zag scan too. Later, in both cases,
the Karhunen-Loeve transform is applied to mentioned blocks. On the other hand,
we present three new metrics based on eigenvalues for a better comparative
evaluation of the techniques. Simulations show that the combined version is the
best, with minor Mean Absolute Error (MAE) and Mean Squared Error (MSE), higher
Peak Signal to Noise Ratio (PSNR) and better image quality. Finally, new
technique was far superior to JPEG and JPEG2000.


title:
Deuteron charge radius and Rydberg constant from spectroscopy data in
  atomic deuterium

abstract:
  We give a pedagogical description of the method to extract the charge radii
and Rydberg constant from laser spectroscopy in regular hydrogen (H) and
deuterium (D) atoms, that is part of the CODATA least-squares adjustment (LSA)
of the fundamental physical constants. We give a deuteron charge radius Rd from
D spectroscopy alone of 2.1415(45) fm. This value is independent of the
measurements that lead to the proton charge radius, and five times more
accurate than the value found in the CODATA Adjustment 10. The improvement is
due to the use of a value for the 1S->2S transition in atomic deuterium which
can be inferred from published data or found in a PhD thesis.


title:
On comparison of the estimators of the Hurst index and the diffusion
  coefficient of the fractional Gompertz diffusion process

abstract:
  We study some estimators of the Hurst index and the diffusion coefficient of
the fractional Gompertz diffusion process and prove that they are strongly
consistent and most of them are asymptotically normal. Moreover, we compare the
asymptotic behavior of these estimators with the aid of computer simulations.


title: Exact Lagrangian Fillings of Legendrian $(2,n)$ torus links

abstract:
  For a Legendrian $(2,n)$ torus knot or link with maximal Thurston-Bennequin
number, Ekholm, Honda, and K\'alm\'an constructed $C_n$ exact Lagrangian
fillings, where $C_n$ is the $n$-th Catalan number. We show that these exact
Lagrangian fillings are pairwise non-isotopic through exact Lagrangian isotopy.
To do that, we compute the augmentations induced by the exact Lagrangian
fillings $L$ to $\mathbb{Z}_2[H_1(L)]$ and distinguish the resulting
augmentations.


title: Energy-dependent correlations in the $S$-matrix of chaotic systems

abstract:
  The $M$-dimensional unitary matrix $S(E)$, which describes scattering of
waves, is a strongly fluctuating function of the energy for complex systems
such as ballistic cavities, whose geometry induces chaotic ray dynamics. Its
statistical behaviour can be expressed by means of correlation functions of the
kind $\left \langle S_{ij}(E+\epsilon)S^\dag_{pq}(E-\epsilon)\right\rangle$,
which have been much studied within the random matrix approach. In this work,
we consider correlations involving an arbitrary number of matrix elements and
express them as infinite series in $1/M$, whose coefficients are rational
functions of $\epsilon$. From a mathematical point of view, this may be seen as
a generalization of the Weingarten functions of circular ensembles.


title: Arbitrary Dicke-State Control of Symmetric Rydberg Ensembles

abstract:
  Symmetric ensembles of neutral atoms interacting via the Rydberg blockade are
well-described by the Jaynes-Cummings Hamiltonian. We use this framework to
study the problem of generating arbitrary superpositions of Dicke states of
hyperfine qubits in such ensembles. The combination of the symmetric Rydberg
blockade and microwaves that drive the qubits with a time-dependent phase is
sufficient to make these ensembles completely controllable, in the sense that
one can generate an arbitrary unitary transformation on the system. We apply
this to the problem of state mapping. With currently feasible parameters, it is
possible to generate arbitrary symmetric states of ~ 10 hypefine qubits with
high fidelity in ~ 1 microsecond, assuming fast microwave phase switching
times. To reduce the requirements on phase switching, we propose a "dressed
ground control" scheme, in which the control task is simplified by restricting
the system's dynamics to the dressed ground subspace.


title: Structural Diversity in Lithium Carbides

abstract:
  The lithium-carbon binary system possesses a broad range of chemical
compounds, which exhibit fascinating chemical bonding characteristics that give
rise diverse and technologically important properties. While lithium carbides
with various compositions have been studied or suggested previously, the
crystal structures of these compounds are far from well understood. In this
work we present the first comprehensive survey of all ground state (GS)
structures of lithium carbides over a broad range of thermodynamic conditions,
using \textit{ab initio} density functional theory (DFT) crystal structure
searching methods. Thorough searches were performed for 29 stoichiometries
ranging from Li$_{12}$C to LiC$_{12}$ at 0 GPa as well as 40 GPa. Based on
formation enthalpies from optimized van der Waals density functional
calculations, three thermodynamically stable phases (Li$_4$C$_3$, Li$_2$C$_2$
and LiC$_{12}$) were identified at 0 GPa, and seven thermodynamically stable
phases (Li$_8$C, Li$_6$C, Li$_4$C, Li$_8$C$_3$, Li$_2$C, Li$_3$C$_4$, and
Li$_2$C$_3$) were predicted at 40 GPa. A rich diversity of carbon bonding,
including monomers, dimers, trimers, nanoribbons, sheets and frameworks, was
found within these structures, and the dimensionality of carbon connectivity
existing within each phase was observed to increase with increasing carbon
concentration. Of particular interest, we find that the well-known composition
LiC$_6$ is actually a metastable one. We also find a unique coexistence of
carbon monomers and dimers within the predicted thermodynamically stable phase
Li$_8$C$_3$, and different widths of carbon nanoribbons coexist in a metastable
phase of Li$_2$C$_2$ (\textit{Imm}2). Interesting mixed
\textit{sp}$^2$-\textit{sp}$^3$ carbon frameworks are predicted in metastable
phases with composition LiC$_6$.


title: On the Pin(2)-equivariant monopole Floer homology of plumbed 3-manifolds

abstract:
  We compute the Pin(2)-equivariant monopole Floer homology for the class of
plumbed 3-manifolds with at most one "bad" vertex (in the sense of Ozsvath and
Szabo). We show that for these manifolds, the Pin(2)-equivariant monopole Floer
homology can be calculated in terms of the Heegaard Floer/monopole Floer
lattice complex defined by Nemethi. Moreover, we prove that in such cases the
ranks of the usual monopole Floer homology groups suffice to determine both the
Manolescu correction terms and the Pin(2)-homology as an abelian group. As an
application of this, we show that $\beta(-Y, s) = \bar{\mu}(Y, s)$ for all
plumbed 3-manifolds with at most one bad vertex, proving a conjecture posed by
Manolescu. Our proof also generalizes results by Stipsicz and Ue relating the
Neumann-Siebenmann invariant with the Ozsvath-Szabo $d$-invariant.


title: Asymptotic Lyapunov exponents for large random matrices

abstract:
  Suppose that A_1,\dots, A_N are independent random matrices whose atoms are
iid copies of a random variable \xi of mean zero and variance one. It is known
from the works of Newman et. al. in the late 80s that when \xi is gaussian then
N^{-1} \log ||A_N \dots A_1|| converges to a non-random limit. We extend this
result to more general matrices with explicit rate of convergence. Our method
relies on a simple connection between structures and dynamics.


title: A note on R\'enyi's "record" problem and Engel's series

abstract:
  In 1973, Williams introduced two interesting discrete Markov processes,
namely $C$-processes and $A$-processes, which are related to record times in
statistics and Engel's series in number theory respectively. Moreover, he
showed that these two processes share the same classical limit theorems, such
as the law of large numbers, central limit theorem and law of the iterated
logarithm. In this paper, we consider the large deviations for these two Markov
processes, which indicate that there is a difference between $C$-processes and
$A$-processes in the context of large deviations.


title:
On logarithmic improvements of critical geodesic restriction bounds in
  the presence of nonpositive curvature

abstract:
  We consider upper bounds on the growth of $L^p$ norms of restrictions of
eigenfunctions and quasimodes to geodesic segments in a nonpositively curved
manifold in the high frequency limit. This sharpens results of Chen and Sogge
as well as Xi and Zhang, which showed that the crux of the problem is to
establish bounds on the mixed partials of the distance function on the covering
manifold restricted to geodesic segments. The innovation in this work is the
development of a formula for the third variation of arc length on the covering
manifold, which allows for a coordinate free expressions of these mixed
partials.


title: Anisotropic cosmological solutions in massive vector theories

abstract:
  In beyond-generalized Proca theories including the extension to theories
higher than second order, we study the role of a spatial component $v$ of a
massive vector field on the anisotropic cosmological background. We show that,
as in the case of the isotropic cosmological background, there is no additional
ghostly degrees of freedom associated with the Ostrogradski instability. In
second-order generalized Proca theories we find the existence of anisotropic
solutions on which the ratio between the anisotropic expansion rate $\Sigma$
and the isotropic expansion rate $H$ remains nearly constant in the
radiation-dominated epoch. In the regime where $\Sigma/H$ is constant, the
spatial vector component $v$ works as a dark radiation with the equation of
state close to $1/3$. During the matter era, the ratio $\Sigma/H$ decreases
with the decrease of $v$. As long as the conditions $|\Sigma| \ll H$ and $v^2
\ll \phi^2$ are satisfied around the onset of late-time cosmic acceleration,
where $\phi$ is the temporal vector component, we find that the solutions
approach the isotropic de Sitter fixed point ($\Sigma=0=v$) in accordance with
the cosmic no-hair conjecture. In the presence of $v$ and $\Sigma$ the early
evolution of the dark energy equation of state $w_{\rm DE}$ in the radiation
era is different from that in the isotropic case, but the approach to the
isotropic value $w_{\rm DE}^{{\rm (iso)}}$ typically occurs at redshifts $z$
much larger than 1. Thus, apart from the existence of dark radiation, the
anisotropic cosmological dynamics at low redshifts is similar to that in
isotropic generalized Proca theories. In beyond-generalized Proca theories the
only consistent solution to avoid the divergence of a determinant of the
dynamical system corresponds to $v=0$, so $\Sigma$ always decreases in time.


title: Discrete Symmetries in Heterotic/F-theory Duality and Mirror Symmetry

abstract:
  We study aspects of Heterotic/F-theory duality for compactifications with
Abelian discrete gauge symmetries. We consider F-theory compactifications on
genus-one fibered Calabi-Yau manifolds with n-sections, associated with the
Tate-Shafarevich group Z_n. Such models are obtained by studying first a
specific toric set-up whose associated Heterotic vector bundle has structure
group Z_n. By employing a conjectured Heterotic/F-theory mirror symmetry we
construct dual geometries of these original toric models, where in the stable
degeneration limit we obtain a discrete gauge symmetry of order two and three,
for compactifications to six dimensions. We provide explicit constructions of
mirror-pairs for symmetric examples with Z_2 and Z_3, in six dimensions. The
Heterotic models with symmetric discrete symmetries are related in field theory
to a Higgsing of Heterotic models with two symmetric abelian U(1) gauge
factors, where due to the Stuckelberg mechanism only a diagonal U(1) factor
remains massless, and thus after Higgsing only a diagonal discrete symmetry of
order n is present in the Heterotic models and detected via Heterotic/F-theory
duality. These constructions also provide further evidence for the conjectured
mirror symmetry in Heterotic/F-theory at the level of fibrations with torsional
sections and those with multi-sections.


title: Charge of dust particles in a particle chain

abstract:
  Charged dust particles form structures which are extended in the vertical
direction in the electrode sheath of a rf discharge when confined within a
glass box. The charge on each particle as a function of height varies due to
the changing plasma conditions and the wakefield of upstream particles. Here an
analysis of the equilibrium state of chains of varying number of particles is
analyzed to determine the charge on each particle within a vertically extended
chain as well as the magnitude of the positive wakefield charge.


title: Quasi-duo differential polynomial rings

abstract:
  In this article we give a characterization of left (right) quasi-duo
differential polynomial rings. In particular, we show that a differential
polynomial ring is left quasi-duo if and only if it is right quasi-duo. This
yields a partial answer to a question posed by Lam and Dugas in 2005. We
provide non-trivial examples of such rings and give a complete description of
the maximal ideals of an arbitrary quasi-duo differential polynomial ring.
Moreover, we show that there is no left (right) quasi-duo differential
polynomial ring in several indeterminates.


title:
Citation success index - An intuitive pair-wise journal comparison
  metric

abstract:
  In this paper we present "citation success index", a metric for comparing the
citation capacity of pairs of journals. Citation success index is the
probability that a random paper in one journal has more citations than a random
paper in another journal (50% means the two journals do equally well). Unlike
the journal impact factor (IF), the citation success index depends on the
broadness and the shape of citation distributions. Also, it is insensitive to
sporadic highly-cited papers that skew the IF. Nevertheless, we show, based on
16,000 journals containing ~2.4 million articles, that the citation success
index is a relatively tight function of the ratio of IFs of journals being
compared, due to the fact that journals with same IF have quite similar
citation distributions. The citation success index grows slowly as a function
of IF ratio. It is substantial (>90%) only when the ratio of IFs exceeds ~6,
whereas a factor of two difference in IF values translates into a modest
advantage for the journal with higher IF (index of ~70%). We facilitate the
wider adoption of this metric by providing an online calculator that takes as
input parameters only the IFs of the pair of journals.


title: Mass spectrometry analysis using MALDIquant

abstract:
  MALDIquant and associated R packages provide a versatile and completely free
open-source platform for analyzing 2D mass spectrometry data as generated for
instance by MALDI and SELDI instruments. We first describe the various methods
and algorithms available in MALDIquant . Subsequently, we illustrate a typical
analysis workflow using MALDIquant by investigating an experimental cancer data
set, starting from raw mass spectrometry measurements and ending at
multivariate classification.


title:
The Carina Project. X. On the kinematics of old and intermediate-age
  stellar populations

abstract:
  We present new radial velocity (RV) measurements of old (horizontal branch)
and intermediate-age (red clump) stellar tracers in the Carina dwarf
spheroidal. They are based on more than 2,200 low-resolution spectra collected
with VIMOS at VLT. The targets are faint (20<V<21.5 mag), but the accuracy at
the faintest limit is <9 kms-1. These data were complemented with RV
measurements either based on spectra collected with FORS2 and FLAMES/GIRAFFE at
VLT or available in the literature. We ended up with a sample of 2748 stars and
among them 1389 are candidate Carina stars. We found that the intermediate-age
stellar component shows a well defined rotational pattern around the minor
axis. The western and the eastern side of the galaxy differ by +5 and -4 km s-1
when compared with the main RV peak. The old stellar component is characterized
by a larger RV dispersion and does not show evidence of RV pattern. We compared
the observed RV distribution with N-body simulations for a former disky dwarf
galaxy orbiting a giant MilkyWay-like galaxy (Lokas et al. 2015). We rotated
the simulated galaxy by 60 degrees with respect to the major axis, we kept the
observer on orbital plane of the dwarf and extracted a sample of stars similar
to the observed one. Observed and predicted Vrot/{\sigma} ratios across the
central regions are in remarkable agreement. This evidence indicates that
Carina was a disky dwarf galaxy that experienced several strong tidal
interactions with the Milky Way. Owing to these interactions, Carina
transformed from a disky to a prolate spheroid and the rotational velocity
transformed into random motions.


title:
Stream-based Online Active Learning in a Contextual Multi-Armed Bandit
  Framework

abstract:
  We study the stream-based online active learning in a contextual multi-armed
bandit framework. In this framework, the reward depends on both the arm and the
context. In a stream-based active learning setting, obtaining the ground truth
of the reward is costly, and the conventional contextual multi-armed bandit
algorithm fails to achieve a sublinear regret due to this cost. Hence, the
algorithm needs to determine whether or not to request the ground truth of the
reward at current time slot. In our framework, we consider a stream-based
active learning setting in which a query request for the ground truth is sent
to the annotator, together with some prior information of the ground truth.
Depending on the accuracy of the prior information, the query cost varies. Our
algorithm mainly carries out two operations: the refinement of the context and
arm spaces and the selection of actions. In our algorithm, the partitions of
the context space and the arm space are maintained for a certain time slots,
and then become finer as more information about the rewards accumulates. We use
a strategic way to select the arms and to request the ground truth of the
reward, aiming to maximize the total reward. We analytically show that the
regret is sublinear and in the same order with that of the conventional
contextual multi-armed bandit algorithms, where no query cost


title:
How to calculate partition functions using convex programming
  hierarchies: provable bounds for variational methods

abstract:
  We consider the problem of approximating partition functions for Ising
models. We make use of recent tools in combinatorial optimization: the
Sherali-Adams and Lasserre convex programming hierarchies, in combination with
variational methods to get algorithms for calculating partition functions in
these families. These techniques give new, non-trivial approximation guarantees
for the partition function beyond the regime of correlation decay. They also
generalize some classical results from statistical physics about the
Curie-Weiss ferromagnetic Ising model, as well as provide a partition function
counterpart of classical results about max-cut on dense graphs
\cite{arora1995polynomial}. With this, we connect techniques from two
apparently disparate research areas -- optimization and counting/partition
function approximations. (i.e. \#-P type of problems).
  Furthermore, we design to the best of our knowledge the first provable,
convex variational methods. Though in the literature there are a host of convex
versions of variational methods \cite{wainwright2003tree, wainwright2005new,
heskes2006convexity, meshi2009convexifying}, they come with no guarantees
(apart from some extremely special cases, like e.g. the graph has a single
cycle \cite{weiss2000correctness}). We consider dense and low threshold rank
graphs, and interestingly, the reason our approach works on these types of
graphs is because local correlations propagate to global correlations --
completely the opposite of algorithms based on correlation decay. In the
process we design novel entropy approximations based on the low-order moments
of a distribution.
  Our proof techniques are very simple and generic, and likely to be applicable
to many other settings other than Ising models.


title:
One spatial dimensional finite volume three-body interaction for a
  short-range potential

abstract:
  In this work, we use McGuire's model to describe scattering of three spinless
identical particles in one spatial dimension, we first present analytic
solutions of Faddeev's equation for scattering of three spinless particles in
free space. The three particles interaction in finite volume is derived
subsequently, and the quantization conditions by matching wave functions in
free space and finite volume are presented in terms of two-body scattering
phase shifts. The quantization conditions obtained in this work for short range
interaction are L\"uscher's formula like and consistent with Yang's results in
\cite{Yang:1967bm}.


title: $B_s\pi^+$ scattering and search for X(5568) with lattice QCD

abstract:
  We investigate $B_s\pi^+$ scattering in s-wave using lattice QCD in order to
search for an exotic resonance X(5568) with flavor $\bar b s \bar d u$; such a
state was recently reported by D0 but was not seen by LHCb. If X(5568) with
$J^P=0^+$ exists, it can strongly decay only to $B_s\pi^+$ and lies
significantly below all other thresholds, which makes a lattice search for
X(5568) cleaner and simpler than for other exotic candidates. Both an elastic
resonance in $B_s\pi^+$ as well as a deeply bound $B^+\bar K^0$ would lead to
distinct signatures in the energies of lattice eigenstates, which are not seen
in our simulation. We therefore do not find a candidate for X(5568) with
$J^P=0^+$ in agreement with the recent LHCb result. The extracted $B_s\pi^+$
scattering length is compatible with zero within the error.


title:
Coevolution of synchronization and cooperation in costly networked
  interactions

abstract:
  Despite the large number of studies on synchronization, the hypothesis that
interactions bear a cost for involved individuals has been considered seldom.
The introduction of costly interactions leads, instead, to the formulation of a
dichotomous scenario in which an individual may decide to cooperate and pay the
cost in order to get synchronized with the rest of the population.
Alternatively, the same individual can decide to free ride, without incurring
in any cost, waiting that others get synchronized to her state. The emergence
of synchronization may thus be seen as the byproduct of an evolutionary game in
which individuals decide their behavior according to the benefit/cost ratio
they accrue in the past. We study the onset of cooperation/synchronization in
networked populations of Kuramoto oscillators and report how topology is
essential in order for cooperation to thrive. We display also how different
classes of topology foster differently synchronization both at a microscopic
and macroscopic level.


title: Arithmetic of the moduli of semistable elliptic surfaces

abstract:
  We prove a new sharp asymptotic with the lower order term of zeroth order on
$\mathcal{Z}_{\mathbb{F}_q(t)}(\mathcal{B})$ for counting the semistable
elliptic curves over $\mathbb{F}_q(t)$ by the bounded height of discriminant
$\Delta(X)$. The precise count is acquired by considering the moduli of
nonsingular semistable elliptic fibrations over $\mathbb{P}^{1}$, also known as
semistable elliptic surfaces, with $12n$ nodal singular fibers and a
distinguished section. We establish a bijection of $K$-points between the
moduli functor of semistable elliptic surfaces and the stack of morphisms
$\mathcal{L}_{1,12n} \cong \mathrm{Hom}_n(\mathbb{P}^{1},
\overline{\mathcal{M}}_{1,1})$ where $\overline{\mathcal{M}}_{1,1}$ is the
Deligne-Mumford stack of stable elliptic curves and $K$ is any field of
characteristic $\neq 2,3$. For $\mathrm{char}(K)=0$, we show that the class of
$\mathrm{Hom}_n(\mathbb{P}^1,\mathcal{P}(a,b))$ in the Grothendieck ring of
$K$-stacks, where $\mathcal{P}(a,b)$ is a 1-dimensional $(a,b)$ weighted
projective stack, is equal to $\mathbb{L}^{(a+b)n+1}-\mathbb{L}^{(a+b)n-1}$.
Consequently, we find that the motive of the moduli $\mathcal{L}_{1,12n}$ is
$\mathbb{L}^{10n + 1}-\mathbb{L}^{10n - 1}$ and the cardinality of the set of
weighted $\mathbb{F}_q$-points to be $\#_q(\mathcal{L}_{1,12n}) = q^{10n +
1}-q^{10n - 1}$. In the end, we formulate an analogous heuristic on
$\mathcal{Z}_{\mathbb{Q}}(\mathcal{B})$ for counting the semistable elliptic
curves over $\mathbb{Q}$ by the bounded height of discriminant $\Delta$ through
the global fields analogy.


title:
The Zig-Zag Process and Super-Efficient Sampling for Bayesian Analysis
  of Big Data

abstract:
  Standard MCMC methods can scale poorly to big data settings due to the need
to evaluate the likelihood at each iteration. There have been a number of
approximate MCMC algorithms that use sub-sampling ideas to reduce this
computational burden, but with the drawback that these algorithms no longer
target the true posterior distribution. We introduce a new family of Monte
Carlo methods based upon a multi-dimensional version of the Zig-Zag process of
(Bierkens, Roberts, 2017), a continuous time piecewise deterministic Markov
process. While traditional MCMC methods are reversible by construction (a
property which is known to inhibit rapid convergence) the Zig-Zag process
offers a flexible non-reversible alternative which we observe to often have
favourable convergence properties. We show how the Zig-Zag process can be
simulated without discretisation error, and give conditions for the process to
be ergodic. Most importantly, we introduce a sub-sampling version of the
Zig-Zag process that is an example of an {\em exact approximate scheme}, i.e.
the resulting approximate process still has the posterior as its stationary
distribution. Furthermore, if we use a control-variate idea to reduce the
variance of our unbiased estimator, then the Zig-Zag process can be
super-efficient: after an initial pre-processing step, essentially independent
samples from the posterior distribution are obtained at a computational cost
which does not depend on the size of the data.


title: A Framework for Estimating Long Term Driver Behavior

abstract:
  The authors present a cyber-physical systems study on the estimation of
driver behavior in autonomous vehicles and vehicle safety systems. Extending
upon previous work, the approach described is suitable for the long term
estimation and tracking of autonomous vehicle behavior. The proposed system
makes use of a previously defined Hybrid State System and Hidden Markov Model
(HSS+HMM) system which has provided good results for driver behavior
estimation. The HSS+HMM system utilizes the hybrid characteristics of
decision-behavior coupling of many systems such as the driver and the vehicle,
uses Kalman Filter estimates of observable parameters to track the
instantaneous continuous state, and estimates the most likely driver state. The
HSS+HMM system is encompassed in a HSS structure and inter-system connectivity
is determined by using Signal Processing and Pattern Recognition techniques.
The proposed method is suitable for scenarios that involve unknown decisions of
other individuals, such as lane changes or intersection precedence/access. The
long term driver behavior estimation system involves an extended HSS+HMM
structure that is capable of including external information in the estimation
process. Through the grafting and pruning of metastates, the HSS+HMM system can
be dynamically updated to best represent driver choices given external
information. Three application examples are also provided to elucidate the
theoretical system.


title:
Refractory period of an excitable semiconductor laser with optical
  injection

abstract:
  Injection-locked semiconductor lasers can be brought to a neuron-like
excitable regime when parameters are set close to the unlocking transition.
Here we study experimentally the response of this system to repeated optical
perturbations and observe the existence of a refractory period during which
perturbations are not able to elicit an excitable response. The results are
analyzed via simulations of a set of dynamical equations which reproduced
adequately the experimental results.


title: On Deterministic Conditions for Subspace Clustering under Missing Data

abstract:
  In this paper we present deterministic conditions for success of sparse
subspace clustering (SSC) under missing data, when data is assumed to come from
a Union of Subspaces (UoS) model. We consider two algorithms, which are
variants of SSC with entry-wise zero-filling that differ in terms of the
optimization problems used to find affinity matrix for spectral clustering. For
both the algorithms, we provide deterministic conditions for any pattern of
missing data such that perfect clustering can be achieved. We provide extensive
sets of simulation results for clustering as well as completion of data at
missing entries, under the UoS model. Our experimental results indicate that in
contrast to the full data case, accurate clustering does not imply accurate
subspace identification and completion, indicating the natural order of
relative hardness of these problems.


title: Impact of Iron-site defects on Superconductivity in LiFeAs

abstract:
  In conventional s-wave superconductors, only magnetic impurities exhibit
impurity bound states, whereas for an s+- order parameter they can occur for
both magnetic and non-magnetic impurities. Impurity bound states in
superconductors can thus provide important insight into the order parameter.
Here, we present a combined experimental and theoretical study of native and
engineered iron-site defects in LiFeAs. Detailed comparison of tunneling
spectra measured on impurities with spin fluctuation theory reveals a
continuous evolution from negligible impurity bound state features for weaker
scattering potential to clearly detectable states for somewhat stronger
scattering potentials. All bound states for these intermediate strength
potentials are pinned at or close to the gap edge of the smaller gap, a
phenomenon that we explain and ascribe to multi-orbital physics.


title:
Output Observability of Systems Over Finite Alphabets with Linear
  Internal Dynamics

abstract:
  We consider a class of systems over finite alphabets with linear internal
dynamics, finite-valued control inputs and finitely quantized outputs. We
motivate the need for a new notion of observability and propose three new
notions of output observability, thereby shifting our attention to the problem
of state estimation for output prediction. We derive necessary and sufficient
conditions for a system to be output observable, algorithmic procedures to
verify these conditions, and a construction of finite memory output observers
when certain conditions are met. We conclude with simple illustrative examples.


title:
Magnetotransport of multiple-band nearly-antiferromagnetic metals due to
  "hot-spot" scattering

abstract:
  Multiple-band electronic structure and proximity to antiferromagnetic (AF)
instability are the key properties of iron-based superconductors. We explore
the influence of scattering by the AF spin fluctuations on transport of
multiple-band metals above the magnetic transition. A salient feature of
scattering on the AF fluctuations is that it is strongly enhanced at the Fermi
surface locations where the nesting is perfect ("hot spots" or "hot lines"). We
review derivation of the collision integral for the Boltzmann equation due to
AF-fluctuations scattering. In the paramagnetic state, the enhanced scattering
rate near the hot lines leads to anomalous behavior of electronic transport in
magnetic field. We explore this behavior by analytically solving Boltzmann
transport equation with approximate transition rates. This approach accounts
for return scattering events and is more accurate than the relaxation-time
approximation. The magnetic-field dependences are characterized by two very
different field scales, the lower scale is set by the hot-spot width and the
higher scale is set by the total scattering amplitude. A conventional
magnetotransport behavior is limited to magnetic fields below the lower scale.
In the wide range in between these two scales the longitudinal conductivity has
linear dependence on the magnetic field and the Hall conductivity has quadratic
dependence. The linear dependence of the diagonal component reflects growth of
the Fermi-surface area affected by hot spots proportional to the magnetic
field. We discuss applicability of this theoretical framework for describing of
anomalous magnetotransport properties in different iron pnictides and selenides
in the paramagnetic state.


title:
Multi-Step Bayesian Optimization for One-Dimensional Feasibility
  Determination

abstract:
  Bayesian optimization methods allocate limited sampling budgets to maximize
expensive-to-evaluate functions. One-step-lookahead policies are often used,
but computing optimal multi-step-lookahead policies remains a challenge. We
consider a specialized Bayesian optimization problem: finding the superlevel
set of an expensive one-dimensional function, with a Markov process prior. We
compute the Bayes-optimal sampling policy efficiently, and characterize the
suboptimality of one-step lookahead. Our numerical experiments demonstrate that
the one-step lookahead policy is close to optimal in this problem, performing
within 98% of optimal in the experimental settings considered.


title:
Representations by Quaternary Quadratic Forms with Coefficients $1$,
  $2$, $5$ or $10$

abstract:
  We determine explicit formulas for the number of representations of a
positive integer $n$ by quaternary quadratic forms with coefficients $1$, $2$,
$5$ or $10$. We use a modular forms approach.


title:
Semiparametric Estimation with Data Missing Not at Random Using an
  Instrumental Variable

abstract:
  Missing data occur frequently in empirical studies in health and social
sciences, often compromising our ability to make accurate inferences. An
outcome is said to be missing not at random (MNAR) if, conditional on the
observed variables, the missing data mechanism still depends on the unobserved
outcome. In such settings, identification is generally not possible without
imposing additional assumptions. Identification is sometimes possible, however,
if an instrumental variable (IV) is observed for all subjects which satisfies
the exclusion restriction that the IV affects the missingness process without
directly influencing the outcome. In this paper, we provide necessary and
sufficient conditions for nonparametric identification of the full data
distribution under MNAR with the aid of an IV. In addition, we give sufficient
identification conditions that are more straightforward to verify in practice.
For inference, we focus on estimation of a population outcome mean, for which
we develop a suite of semiparametric estimators that extend methods previously
developed for data missing at random. Specifically, we propose inverse
probability weighted estimation, outcome regression-based estimation and doubly
robust estimation of the mean of an outcome subject to MNAR. For illustration,
the methods are used to account for selection bias induced by HIV testing
refusal in the evaluation of HIV seroprevalence in Mochudi, Botswana, using
interviewer characteristics such as gender, age and years of experience as IVs.


title:
Normal state of metal-intercalated phenacene crystals: Role of electron
  correlations

abstract:
  In this work we study the effect of long range electron-electron correlations
on the behavior of the normal state of metal-intercalated phenacene crystals.
While the individual phenacene molecules are modeled by the Pariser-Parr-Pople
Hamiltonian with long range Coulomb interactions, we derive a correlated
minimal model for describing the phenacene ionic crystals. We find that long
range electron correlations do not change the behavior of the phenacene ions
with molecular valence $-1$ (monoanion) and $-2$ (dianion), compared to that
observed for short range electron interactions. The monoanion crystal is a
single-band $\frac{1}{2}$-filled antiferromagnetic Mott-Hubbard semiconductor
while the dianion crystal is a two-band semiconductor with inter-molecular
antiferromagnetic and intra-molecular ferromagnetic spin orderings. However,
the trianion crystal is no longer a nearly degenerate $\frac{3}{4}$-filled
two-band system. We show that this occurs because the kinetic stability of the
$\frac{3}{4}$-filled two-band system with long range correlations is smaller
compared to that with short range correlations, for the lattice sizes
considered in this study. We argue that with large finite lattices, behavior of
the trianion crystal with long range correlations will be same as that with
short range correlations. We thus conclude that long range correlations fail to
alter the normal states of metal-intercalated phenacene crystals.


title:
Congruences between word length statistics for the finitary alternating
  and symmetric groups

abstract:
  In a recent paper, Bacher and de la Harpe study conjugacy growth series of
infinite permutation groups and their relationships with $p(n)$, the partition
function, and $p(n)_{\textbf{e}}$, a generalized partition function. They prove
identities for the conjugacy growth series of the finitary symmetric group and
the finitary alternating group. The group theory also motivates an
investigation into congruence relationships between the finitary symmetric
group and the finitary alternating group. Using the Ramanujan congruences for
the partition function $p(n)$ and Atkin's generalization to the $k$-colored
partition function $p_{k}(n)$, we prove the existence of congruence relations
between these two series modulo arbitrary powers of 5 and 7, which we
systematically describe. Furthermore, we prove that such relationships exist
modulo powers of all primes $\ell\geq 5$.


title:
Qualitative Judgement of Research Impact: Domain Taxonomy as a
  Fundamental Framework for Judgement of the Quality of Research

abstract:
  The appeal of metric evaluation of research impact has attracted considerable
interest in recent times. Although the public at large and administrative
bodies are much interested in the idea, scientists and other researchers are
much more cautious, insisting that metrics are but an auxiliary instrument to
the qualitative peer-based judgement. The goal of this article is to propose
availing of such a well positioned construct as domain taxonomy as a tool for
directly assessing the scope and quality of research. We first show how
taxonomies can be used to analyse the scope and perspectives of a set of
research projects or papers. Then we proceed to define a research team or
researcher's rank by those nodes in the hierarchy that have been created or
significantly transformed by the results of the researcher. An experimental
test of the approach in the data analysis domain is described. Although the
concept of taxonomy seems rather simplistic to describe all the richness of a
research domain, its changes and use can be made transparent and subject to
open discussions.


title:
The modification of the pore characteristics of activated carbon, for
  use in electrical double layer capacitors, through plasma processing

abstract:
  It was aimed to determine whether plasma processing could contribute to
enhanced capacitance and energy density of activated carbon electrode based
electrochemical capacitors, through the formation of additional surface
charges. While an increase of up to 35% of the gravimetric capacitance, along
with ~ 20% decrease in resistance, was obtained through optimal plasma
processing, increased plasma exposure yielded a drastic reduction (/increase)
in the capacitance (/resistance). It was also found that the capacitance and
resistance modulation was a sensitive function of sample processing as well as
electrochemical testing procedure. Considering the complexity of modeling
realistic porous matrices, a metric to parameterize the reach of an electrolyte
into the matrix has been posited.


title: Rapid Prediction of Player Retention in Free-to-Play Mobile Games

abstract:
  Predicting and improving player retention is crucial to the success of mobile
Free-to-Play games. This paper explores the problem of rapid retention
prediction in this context. Heuristic modeling approaches are introduced as a
way of building simple rules for predicting short-term retention. Compared to
common classification algorithms, our heuristic-based approach achieves
reasonable and comparable performance using information from the first session,
day, and week of player activity.


title: Light speed variation from gamma-ray bursts

abstract:
  The effect of quantum gravity can bring a tiny light speed variation which is
detectable through energetic photons propagating from gamma ray bursts (GRBs)
to an observer such as the space observatory. Through an analysis of the
energetic photon data of the GRBs observed by the Fermi Gamma-ray Space
Telescope (FGST), we reveal a surprising regularity of the observed time lags
between photons of different energies with respect to the Lorentz violation
factor due to the light speed energy dependence. Such regularity suggests a
linear form correction of the light speed $v(E)=c(1-E/E_{\rm LV})$, where $E$
is the photon energy and $E_{\rm LV}=(3.60 \pm 0.26) \times 10^{17}~ \rm GeV$
is the Lorentz violation scale measured by the energetic photon data of GRBs.
The results support an energy dependence of the light speed in cosmological
space.


title:
Information Projection and Approximate Inference for Structured Sparse
  Variables

abstract:
  Approximate inference via information projection has been recently introduced
as a general-purpose approach for efficient probabilistic inference given
sparse variables. This manuscript goes beyond classical sparsity by proposing
efficient algorithms for approximate inference via information projection that
are applicable to any structure on the set of variables that admits enumeration
using a \emph{matroid}. We show that the resulting information projection can
be reduced to combinatorial submodular optimization subject to matroid
constraints. Further, leveraging recent advances in submodular optimization, we
provide an efficient greedy algorithm with strong optimization-theoretic
guarantees. The class of probabilistic models that can be expressed in this way
is quite broad and, as we show, includes group sparse regression, group sparse
principal components analysis and sparse canonical correlation analysis, among
others. Moreover, empirical results on simulated data and high dimensional
neuroimaging data highlight the superior performance of the information
projection approach as compared to established baselines for a range of
probabilistic models.


title:
Stock Market Market Crash of 2008: an empirical study of the deviation
  of share prices from company fundamentals

abstract:
  The aim of this study is to investigate quantitatively whether share prices
deviated from company fundamentals in the stock market crash of 2008. For this
purpose, we use a large database containing the balance sheets and share prices
of 7,796 worldwide companies for the period 2004 through 2013. We develop a
panel regression model using three financial indicators--dividends per share,
cash flow per share, and book value per share--as explanatory variables for
share price. We then estimate individual company fundamentals for each year by
removing the time fixed effects from the two-way fixed effects model, which we
identified as the best of the panel regression models. One merit of our model
is that we are able to extract unobservable factors of company fundamentals by
using the individual fixed effects.
  Based on these results, we analyze the market anomaly quantitatively using
the divergence rate--the rate of the deviation of share price from a company's
fundamentals. We find that share prices on average were overvalued in the
period from 2005 to 2007, and were undervalued significantly in 2008, when the
global financial crisis occurred. Share prices were equivalent to the
fundamentals on average in the subsequent period. Our empirical results clearly
demonstrate that the worldwide stock market fluctuated excessively in the time
period before and just after the global financial crisis of 2008.


title: A calculus proof of the Cram\'er-Wold theorem

abstract:
  We present a short, elementary proof not involving Fourier transforms of the
theorem of Cram\'er and Wold that a Borel probability measure is determined by
its values on half-spaces.


title: Modular Quantum Information Processing by Dissipation

abstract:
  Dissipation can be used as a resource to control and simulate quantum
systems. We discuss a modular model based on fast dissipation capable of
performing universal quantum computation, and simulating arbitrary Lindbladian
dynamics. The model consists of a network of elementary dissipation-generated
modules and it is in principle scalable. In particular, we demonstrate the
ability to dissipatively prepare all single qubit gates, and the CNOT gate;
prerequisites for universal quantum computing. We also show a way to implement
a type of quantum memory in a dissipative environment, whereby we can
arbitrarily control the loss in both coherence, and concurrence, over the
evolution. Moreover, our dissipation-assisted modular construction exhibits a
degree of inbuilt robustness to Hamiltonian, and indeed Lindbladian errors, and
as such is of potential practical relevance.


title: Sober metric approach spaces

abstract:
  It is proved that a metric space is sober, as an approach space, if and only
if it is Smyth complete.


title:
Intervalley scattering of graphene massless Dirac fermions at 3-periodic
  grain boundaries

abstract:
  We study how low-energy charge carriers scatter off periodic and linear
graphene grain boundaries oriented along the zigzag direction with a
periodicity three times greater than that of pristine graphene. These defects
map the two Dirac points into the same position, and thus allow for intervalley
scattering to occur. Starting from graphene's first-neighbor tight-binding
model we show how can we compute the boundary condition seen by graphene's
massless Dirac fermions at such grain boundaries. We illustrate this procedure
for the 3-periodic pentagon-only grain boundary, and then work out the
low-energy electronic scattering off this linear defect. We also compute the
effective generalized potential seen by the Dirac fermions at the grain
boundary region.


title: ISR effects for resonant Higgs production at future lepton colliders

abstract:
  We study the effects of the initial state radiation on the $s$-channel Higgs
boson resonant production at $\mu^+\mu^-$ and $e^+e^-$ colliders by convoluting
with the beam energy spread profile of the collider and the Breit-Wigner
resonance profile of the signal. We assess their impact on both the Higgs
signal and SM backgrounds for the leading decay channels $h\rightarrow b\bar
b,\ WW^*$. Our study improves the existing analyses of the proposed future
resonant Higgs factories and provides further guidance for the accelerator
designs with respect to the physical goals.


title: P\'olya urns with immigration at random times

abstract:
  We study the number of white balls in a classical P\'olya urn model with the
additional feature that, at random times, a black ball is added to the urn. The
number of draws between these random times are i.i.d. and, under certain moment
conditions on the inter-arrival distribution, we characterize the limiting
distribution of the (properly scaled) number of white balls as the number of
draws goes to infinity. The possible limiting distributions obtained in this
way vary considerably depending on the inter-arrival distribution and are
difficult to describe explicitly. However, we show that the limits are fixed
points of certain probabilistic distributional transformations, and this fact
provides a proof of convergence and leads to properties of the limits. The
model can alternatively be viewed as a preferential attachment random graph
model where added vertices initially have a random number of edges, and from
this perspective, our results describe the limit of the degree of a fixed
vertex.


abstract:
  This paper studies Yoneda completeness and flat completeness of ordered fuzzy
sets valued in the quantale obtained by endowing the unit interval with a
continuous triangular norm. Both of these notions are natural extension of
directed completeness in order theory to the fuzzy setting. Yoneda completeness
requires every forward Cauchy net converges (has a Yoneda limit), while flat
completeness requires every flat weight (a counterpart of ideals in partially
ordered sets) has a supremum. It is proved that flat completeness implies
Yoneda completeness, but, the converse implication holds only in the case that
the related triangular norm is either isomorphic to the Lukasiewicz t-norm or
to the product t-norm.


title: Minimum-Time Selective Control of Homonuclear Spins

abstract:
  In NMR (Nuclear Magnetic Resonance) quantum computation, the selective
control of multiple homonuclear spins is usually slow because their resonance
frequencies are very close to each other. To quickly implement controls against
decoherence effects, this paper presents an efficient numerical algorithm
fordesigning minimum-time local transformations in two homonuclear spins. We
obtain an accurate minimum-time estimation via geometric analysis on the
two-timescale decomposition of the dynamics. Such estimation narrows down the
range of search for the minimum-time control with a gradient-type optimization
algorithm. Numerical simulations show that this method can remarkably reduce
the search efforts, especially when the frequency difference is very small and
the control field is high. Its effectiveness is further demonstrated by NMR
experiments with two homunuclear carbon spins in a trichloroethylene (C2H1Cl3)
sample system.


title: Inclusion properties of Orlicz and weak Orlicz spaces

abstract:
  In this paper we discuss the structure of Orlicz spaces and weak Orlicz
spaces on $\mathbb{R}^n$. We obtain some necessary and sufficient conditions
for the inclusion property of these spaces. One of the keys is to compute the
norm of the characteristic functions of the balls in $\mathbb{R}^n$.


title: Survey of finiteness results for hyperk\"ahler manifolds

abstract:
  This paper is a survey of finiteness results in hyperk\"ahler geometry. We
review some classical theorems by Sullivan, Koll\'ar-Matsusaka, Huybrechts, as
well as theorems in the recent literature by Charles, Sawon, and joint results
of the author with Verbitsky. We also strengthen a finiteness theorem of the
author. These are extended notes of the author's talk during the closing
conference of the Simons Semester in the Banach Center in B\c{e}dlewo, Poland.


title: Nonlinear Jaynes-Cummings model for two interacting two-level atoms

abstract:
  In this work we examine a nonlinear version of the Jaynes-Cummings model for
two identical two-level atoms allowing for Ising-like and dipole-dipole
interplays between them. The model is said to be nonlinear in the sense that it
can incorporate both a general intensity-dependent interaction between the
atomic system and the cavity field and/or the presence of a nonlinear medium
inside the cavity. As an example, we consider a particular type of atom-field
coupling based upon the so-called Buck-Sukumar model and a lossless Kerr-like
cavity. We describe the possible effects of such features on the evolution of
some quantities of current interest, such as atomic excitation, purity,
concurrence, the entropy of the field and the evolution of the latter in phase
space.


title: Gaussian curvature and gyroscopes

abstract:
  We relate Gaussian curvature to the gyroscopic force, thus giving a
mechanical interpretation of the former and a geometrical interpretation of the
latter. We do so by considering the motion of a spinning disk constrained to be
tangent to a curved surface. It is shown that the spin gives rise to a force on
the disk which is equal to the magnetic force on a point charge moving in a
magnetic field normal to the surface, of magnitude equal to the Gaussian
curvature, and of charge equal to the disk's axial spin. In a special case,
this demonstrates that the precession of Lagrange's top is due to the curvature
of a sphere determined by the parameters of the top.