title: Can DMD obtain a Scene Background in Color?

abstract:
  A background model describes a scene without any foreground objects and has a
number of applications, ranging from video surveillance to computational
photography. Recent studies have introduced the method of Dynamic Mode
Decomposition (DMD) for robustly separating video frames into a background
model and foreground components. While the method introduced operates by
converting color images to grayscale, we in this study propose a technique to
obtain the background model in the color domain. The effectiveness of our
technique is demonstrated using a publicly available Scene Background
Initialisation (SBI) dataset. Our results both qualitatively and quantitatively
show that DMD can successfully obtain a colored background model.


title: Embedding of groups and quadratic equations over groups

abstract:
  We prove that, for every integer $n \ge 2$, a finite or infinite countable
group $G$ can be embedded into a 2-generated group $H$ in such a way that the
solvability of quadratic equations of length at most $n$ is preserved, i.e.,
every quadratic equation over $G$ of length at most $n$ has a solution in $G$
if and only if this equation, considered as an equation over $H$, has a
solution in $H$.


title: Linearly Embeddable Designs

abstract:
  A residual design ${\cal{D}}_B$ with respect to a block $B$ of a given design
$\cal{D}$ is defined to be linearly embeddable over $GF(p)$ if the $p$-ranks of
the incidence matrices of ${\cal{D}}_B$ and $\cal{D}$ differ by one. A
sufficient condition for a residual design to be linearly embeddable is proved
in terms of the minimum distance of the linear code spanned by the incidence
matrix, and this condition is used to show that the residual designs of several
known infinite classes of designs are linearly embeddable. A necessary
condition for linear embeddability is proved for affine resolvable designs and
their residual designs. As an application, it is shown that a residual design
of the classical affine design of the planes in $AG(3,2^2)$ admits two
nonisomorphic embeddings over $GF(2)$ that give rise to the only known
counter-examples of Hamada's conjecture over a field of non-prime order.


title: Prospects for Testing Lorentz and CPT Invariance in the Top-Quark Sector

abstract:
  We present how to further the search for Lorentz and CPT violation in the
top-quark sector after the first measurement in this sector by D0. We compute
the Lorentz-violating matrix element for top pair production via gluon fusion,
which allows a similar but more precise measurement at the LHC. For CPT
violation, we analyze single-top production, derive the modified matrix
elements, and predict possible signals.


title: Prior-based Coregistration and Cosegmentation

abstract:
  We propose a modular and scalable framework for dense coregistration and
cosegmentation with two key characteristics: first, we substitute ground truth
data with the semantic map output of a classifier; second, we combine this
output with population deformable registration to improve both alignment and
segmentation. Our approach deforms all volumes towards consensus, taking into
account image similarities and label consistency. Our pipeline can incorporate
any classifier and similarity metric. Results on two datasets, containing
annotations of challenging brain structures, demonstrate the potential of our
method.


title: Boltzmannian Equilibrium in Stochastic Systems

abstract:
  Equilibrium is a central concept of statistical mechanics. In previous work
we introduced the notions of a Boltzmannian alpha-epsilon-equilibrium and a
Boltzmannian gamma-varepsilon-equilibrium (Werndl and Frigg 2015a, 2015b). This
was done in a deterministic context. We now consider systems with a stochastic
micro-dynamics and transfer these notions from the deterministic to the
stochastic context. We then prove stochastic equivalents of the Dominance
Theorem and the Prevalence Theorem. This establishes that also in stochastic
systems equilibrium macro-regions are large in requisite sense.


title:
Using machine learning to identify factors that govern amorphization of
  irradiated pyrochlores

abstract:
  Structure-property relationships is a key materials science concept that
enables the design of new materials. In the case of materials for application
in radiation environments, correlating radiation tolerance with fundamental
structural features of a material enables materials discovery. Here, we use a
machine learning model to examine the factors that govern amorphization
resistance in the complex oxide pyrochlore ($A_2B_2$O$_7$). We examine the
fidelity of predictions based on cation radii and electronegativities, the
oxygen positional parameter, and the energetics of disordering and amorphizing
the material. No one factor alone adequately predicts amorphization resistance.
We find that, when multiple families of pyrochlores (with different B cations)
are considered, radii and electronegativities provide the best prediction but
when the machine learning model is restricted to only the $B$=Ti pyrochlores,
the energetics of disordering and amorphization are optimal. This work provides
new insight into the factors that govern the amorphization susceptibility and
highlights the ability of machine learning approaches to generate that insight.


title:
Magnon-induced long-range correlations and their neutron-scattering
  signature in quantum magnets

abstract:
  We consider the coupling of the magnons in both quantum ferromagnets and
antiferromagnets to the longitudinal order-parameter fluctuations, and the
resulting nonanalytic behavior of the longitudinal susceptibility. In classical
magnets it is well known that long-range correlations induced by the magnons
lead to a singular wave-number dependence of the form $1/k^{4-d}$ in all
dimensions 2<d<4, for both ferromagnets and antiferromagnets. At zero
temperature we find a profound difference between the two cases. Consistent
with naive power counting, the longitudinal susceptibility in a quantum
antiferromagnet scales as $k^{d-3}$ for 1<d<3, whereas in a quantum ferromagnet
the analogous result, $k^{d-2}$, is absent due to a zero scaling function. This
absence of a nonanalyticity in the longitudinal susceptibility is due to the
lack of magnon number fluctuations in the ground state of a quantum
ferromagnet; correlation functions that are sensitive to other fluctuations do
exhibit the behavior predicted by simple power counting. Also of interest is
the dynamical behavior as expressed in the longitudinal part of the dynamical
structure factor, which is directly measurable via neutron scattering. For both
ferromagnets and antiferromagnets there is a logarithmic singularity at the
magnon frequency with a prefactor that vanishes as $T\to 0$. In the
antiferromagnetic case there also is a nonzero contribution at T=0 that is
missing for ferromagnets. Magnon damping due to quenched disorder restores the
expected scaling behavior of the longitudinal susceptibility in the
ferromagnetic case; it scales as $k^{d-2}$ if the order parameter is not
conserved, or as $k^d$ if it is. Detailed predictions are made for both two-
and three-dimensional systems at both T=0 and in the limit of low temperatures,
and the physics behind the various nonanalytic behaviors is discussed.


title: From the Coulomb breakup of halo nuclei to neutron radiative capture

abstract:
  Coulomb breakup is used to infer radiative-capture cross sections at
astrophysical energies. We test theoretically the accuracy of this indirect
technique in the particular case of 15C, for which both the Coulomb breakup to
^{14}C+n and the radiative capture 14C(n,{\gamma})15C have been measured. We
analyse the dependance of Coulomb-breakup calculations on the projectile
description in both its initial bound state and its continuum. Our calculations
depend not only on the Asymptotic Normalisation Coefficient (ANC) of the 15C
ground state, but also on the 14C-n continuum. This questions the method
proposed by Summers and Nunes [Phys. Rev. C 78, 011601 (2008), ibid. 78, 069908
(2008)], which assumes that an ANC can be directly extracted from the
comparison of calculations to breakup data. Fortunately, the sensitivity to the
continuum description can be absorbed in a normalisation constant obtained by a
simple {\chi}2 fit of our calculations to the measurements. By restricting this
fit to low 14C-n energy in the continuum, we can achieve a better agreement
between the radiative-capture cross sections inferred from the Coulomb-breakup
method and the exact ones. This result revives the Coulomb-breakup technique to
infer neutron radiative-capture capture to loosely-bound states, which would be
very useful for r- and s-process modelling in explosive stellar environments.


title: Rate-Distortion Dimension of Stochastic Processes

abstract:
  The rate-distortion dimension (RDD) of an analog stationary process is
studied as a measure of complexity that captures the amount of information
contained in the process. It is shown that the RDD of a process, defined as two
times the asymptotic ratio of its rate-distortion function $R(D)$ to $\log
{1\over D}$ as the distortion $D$ approaches zero, is equal to its information
dimension (ID). This generalizes an earlier result by Kawabata and Dembo and
provides an operational approach to evaluate the ID of a process, which
previously was shown to be closely related to the effective dimension of the
underlying process and also to the fundamental limits of compressed sensing.
The relation between RDD and ID is illustrated for a piecewise constant
process.


title: On the Impact of a Single Edge on the Network Coding Capacity

abstract:
  In this paper, we study the effect of a single link on the capacity of a
network of error-free bit pipes. More precisely, we study the change in network
capacity that results when we remove a single link of capacity $\delta$. In a
recent result, we proved that if all the sources are directly available to a
single super-source node, then removing a link of capacity $\delta$ cannot
change the capacity region of the network by more than $\delta$ in each
dimension. In this paper, we extend this result to the case of multi-source,
multi-sink networks for some special network topologies.


title:
An ensemble learning method for scene classification based on Hidden
  Markov Model image representation

abstract:
  Low level images representation in feature space performs poorly for
classification with high accuracy since this level of representation is not
able to project images into the discriminative feature space. In this work, we
propose an efficient image representation model for classification. First we
apply Hidden Markov Model (HMM) on ordered grids represented by different type
of image descriptors in order to include causality of local properties existing
in image for feature extraction and then we train up a separate classifier for
each of these features sets. Finally we ensemble these classifiers efficiently
in a way that they can cancel out each other errors for obtaining higher
accuracy. This method is evaluated on 15 natural scene dataset. Experimental
results show the superiority of the proposed method in comparison to some
current existing methods


title: Network structure and patterns of information diversity on Twitter

abstract:
  Social media have great potential to support diverse information sharing, but
there is widespread concern that platforms like Twitter do not result in
communication between those who hold contradictory viewpoints. Because users
can choose whom to follow, prior research suggests that social media users
exist in 'echo chambers' or become polarized. We seek evidence of this in a
complete cross section of hyperlinks posted on Twitter, using previously
validated measures of the political slant of news sources to study information
diversity. Contrary to prediction, we find that the average account posts links
to more politically moderate news sources than the ones they receive in their
own feed. However, members of a tiny network core do exhibit cross-sectional
evidence of polarization and are responsible for the majority of tweets
received overall due to their popularity and activity, which could explain the
widespread perception of polarization on social media.


title: Metastable dynamics for hyperbolic variations of the Allen-Cahn equation

abstract:
  Metastable dynamics of a hyperbolic variation of the Allen-Cahn equation with
homogeneous Neumann boundary conditions are considered. Using the "dynamical
approach" proposed by Carr-Pego [10] and Fusco-Hale [19] to study
slow-evolution of solutions in the classic parabolic case, we prove existence
and persistence of metastable patterns for an exponentially long time. In
particular, we show the existence of an "approximately invariant"
$N$-dimensional manifold $\mathcal{M}_0$ for the hyperbolic Allen-Cahn
equation: if the initial datum is in a tubular neighborhood of $\mathcal{M}_0$,
the solution remains in such neighborhood for an exponentially long time.
Moreover, the solution has $N$ transition layers and the transition points move
with exponentially small velocity. In addition, we determine the explicit form
of a system of ordinary differential equations describing the motion of the
transition layers and we analyze the differences with the corresponding motion
valid for the parabolic case.


title:
A probabilistic patch based image representation using Conditional
  Random Field model for image classification

abstract:
  In this paper we proposed an ordered patch based method using Conditional
Random Field (CRF) in order to encode local properties and their spatial
relationship in images to address texture classification, face recognition, and
scene classification problems. Typical image classification approaches work
without considering spatial causality among distinctive properties of an image
for image representation in feature space. In this method first, each image is
encoded as a sequence of ordered patches, including local properties. Second,
the sequence of these ordered patches is modeled as a probabilistic feature
vector by CRF to model spatial relationship of these local properties. And
finally, image classification is performed on such probabilistic image
representation. Experimental results on several standard image datasets
indicate that proposed method outperforms some of existing image classification
methods.


title:
Apocenter glow in eccentric debris disks: implications for Fomalhaut and
  epsilon Eridani

abstract:
  Debris disks often take the form of eccentric rings with azimuthal
asymmetries in surface brightness. Such disks are often described as showing
"pericenter glow", an enhancement of the disk brightness in regions nearest the
central star. At long wavelengths, however, the disk apocenters should appear
brighter than their pericenters: in the long wavelength limit, we find the
apocenter/pericenter flux ratio scales as 1+e for disk eccentricity e. We
produce new models of this "apocenter glow" to explore its causes and
wavelength dependence and study its potential as a probe of dust grain
properties. Based on our models, we argue that several far-infrared and
(sub)millimeter images of the Fomalhaut and epsilon Eridani debris rings
obtained with Herschel, JCMT, SHARC II, ALMA, and ATCA should be reinterpreted
as suggestions or examples of apocenter glow. This reinterpretation yields new
constraints on the disks' dust grain properties and size distributions.


title:
Monte Carlo simulations of Higgs-boson production at the LHC with the
  KrkNLO method

abstract:
  We present numerical tests and predictions of the KrkNLO method for matching
of NLO QCD corrections to hard processes with LO parton shower Monte Carlo
generators (NLO+PS). This method was described in detail in our previous
publications, where it was also compared with other NLO+PS matching approaches
(MC@NLO and POWHEG) as well as fixed-order NLO and NNLO calculations. Here we
concentrate on presenting some numerical results (cross sections and
distributions) for $Z/\gamma^*$ (Drell-Yan) and Higgs-boson production
processes at the LHC. The Drell--Yan process is used mainly to validate the
KrkNLO implementation in the Herwig 7 program with respect to the previous
implementation in Sherpa. We also show predictions for this process with the
new, complete, MC-scheme parton distribution functions and compare them with
our previously published results. Then, we present the first results of the
KrkNLO method for Higgs production in gluon-gluon fusion at the LHC and compare
them with MC@NLO and POWHEG predictions from Herwig 7 fixed-order results from
HNNLO and a resummed calculation from HqT, as well as with experimental data
from the ATLAS collaboration.


title: Dynamical Transitions in a Dragged Growing Polymer Chain

abstract:
  We extend the Rouse model of polymer dynamics to situations of non-stationary
chain growth. For a dragged polymer chain of length $N(t) = t^\alpha$, we find
two transitions in conformational dynamics. At $\alpha= 1/2$, the propagation
of tension and the average shape of the chain change qualitatively, while at
$\alpha = 1 $ the average center-of-mass motion stops. These transitions are
due to a simple physical mechanism: a race duel between tension propagation and
polymer growth. Therefore they should also appear for growing semi-flexible or
stiff polymers. The generalized Rouse model inherits much of the versatility of
the original Rouse model: it can be efficiently simulated and it is amenable to
analytical treatment.


title: High-dimensional regression adjustments in randomized experiments

abstract:
  We study the problem of treatment effect estimation in randomized experiments
with high-dimensional covariate information, and show that essentially any
risk-consistent regression adjustment can be used to obtain efficient estimates
of the average treatment effect. Our results considerably extend the range of
settings where high-dimensional regression adjustments are guaranteed to
provide valid inference about the population average treatment effect. We then
propose cross-estimation, a simple method for obtaining finite-sample-unbiased
treatment effect estimates that leverages high-dimensional regression
adjustments. Our method can be used when the regression model is estimated
using the lasso, the elastic net, subset selection, etc. Finally, we extend our
analysis to allow for adaptive specification search via cross-validation, and
flexible non-parametric regression adjustments with machine learning methods
such as random forests or neural networks.


title: Trimmed L-moments For Estimation Multi-parameter Archimedean Copulas

abstract:
  Trimmed L-moments, were introduced by Elamir and Seheult(2003) to proposed a
new estimation method for multi-parameter distributions when the mean doesn't
exist or for heavy tailed distribution where the L-moments method which
proposed by Hosking (1990) is not valid because the absence of theoretical
L-moments. In this paper a new estimation method based on trimmed L-moments of
multi-parameter copulas is proposed with a simulation study. The consistency
and the asymptotic normality of the new estimator also established.


title:
Restoring highly corrupted images by impulse noise using radial basis
  functions interpolation

abstract:
  Preserving details in restoring images highly corrupted by impulse noise
remains a challenging problem. We proposed an algorithm based on radial basis
functions (RBF) interpolation which estimates the intensities of corrupted
pixels by their neighbors. In this algorithm, first intensity values of noisy
pixels in the corrupted image are estimated using RBFs. Next, the image is
smoothed. The proposed algorithm can effectively remove the highly dense
impulse noise. Experimental results show the superiority of the proposed
algorithm in comparison to the recent similar methods both in noise suppression
and detail preservation. Extensive simulations show better results in measure
of peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM),
especially when the image is corrupted by very highly dense impulse noise.


title: Active phases and flickering of a symbiotic recurrent nova T CrB

abstract:
  T CrB is a symbiotic recurrent nova known to exhibit active phases,
characterised by apparent increases in the hot component temperature and the
appearance of flickering, i.e. changes in the observed flux on the time-scale
of minutes. Historical UV observations have ruled out orbital variability as an
explanation for flickering and instead suggest flickering is caused by variable
mass transfer. We have analysed optical and X-ray observations to investigate
the nature of the flickering as well as the active phases in T CrB. The
spectroscopic and photometric observations confirm that the active phases
follow two periods of ~1000d and ~5000d. Flickering in the X-rays is detected
and follows an amplitude-flux relationship similar to that observed in the
optical. The flickering is most prominent at harder X-ray energies, suggesting
that it originates in the boundary layer between the accretion disc and the
white dwarf. The X-ray radiation from the boundary layer is then reprocessed by
a thick accretion disc or a nebula into UV radiation. A more detailed
understanding of flickering would benefit from long-term simultaneous X-ray and
optical monitoring of the phenomena in symbiotic recurrent novae and related
systems such as Z And type symbiotic stars.


title:
Background constraints in the infinite tension limit of the heterotic
  string

abstract:
  In this work we investigate the classical constraints imposed on the
supergravity and super Yang-Mills backgrounds in the $\alpha'\to 0$ limit of
the heterotic string using the pure spinor formalism. Guided by the recently
observed sectorization of the model, we show that all the ten-dimensional
constraints are elegantly obtained from the single condition of nilpotency of
the BRST charge.


title:
An energy-based interaction model for population opinion dynamics with
  topic coupling

abstract:
  We introduce a new, and quite general variational model for opinion dynamics
based on pairwise interaction potentials and a range of opinion evolution
protocols ranging from random interactions to global synchronous flows in the
opinion state space. The model supports the concept of topic "coupling",
allowing opinions held by individuals to be changed via indirect interaction
with others on different subjects. Interaction topology is governed by a graph
that determines interactions. Our model, which is really a family of
variational models, has, as special cases, many of the previously established
models for the opinion dynamics. After introducing the model, we study the
dynamics of the special case in which the potential is either a tent function
or a constructed bell-like curve. We find that even in these relatively simple
potential function examples there emerges interesting behavior. We also present
results of preliminary numerical explorations of the behavior of the model to
motivate questions that can be explored analytically.


title:
Accounting for the Role of Long Walks on Networks via a New Matrix
  Function

abstract:
  We introduce a new matrix function for studying graphs and real-world
networks based on a double-factorial penalization of walks between nodes in a
graph. This new matrix function is based on the matrix error function. We find
a very good approximation of this function using a matrix hyperbolic tangent
function. We derive a communicability function, a subgraph centrality and a
double-factorial Estrada index based on this new matrix function. We obtain
upper and lower bounds for the double-factorial Estrada index of graphs,
showing that they are similar to those of the single-factorial Estrada index.
We then compare these indices with the single-factorial one for simple graphs
and real-world networks. We conclude that for networks containing chordless
cycles---holes---the two penalization schemes produce significantly different
results. In particular, we study two series of real-world networks representing
urban street networks, and protein residue networks. We observe that the
subgraph centrality based on both indices produce significantly different
ranking of the nodes. The use of the double factorial penalization of walks
opens new possibilities for studying important structural properties of
real-world networks where long-walks play a fundamental role, such as the cases
of networks containing chordless cycles.


title: Kronecker Product Graphs and Counting Walks in Restricted Lattices

abstract:
  Formulas are derived for counting walks in the Kronecker product of graphs,
and the associated spectral distributions are obtained by the Mellin
convolution of probability distributions. Two-dimensional restricted lattices
admitting the Kronecker product structure are listed, and their spectral
distributions are calculated in terms of elliptic integrals.


title:
Swing lattice game and a short proof of the swing lemma for planar
  semimodular lattices

abstract:
  The swing lemma, due to G. Gr\"atzer for slim semimodular lattices and
extended by G. Cz\'edli and G. Gr\"atzer for all planar semimodular lattices,
describes the congruence generated by a prime interval in an efficient way.
Here we present a new proof for this lemma, which is shorter than the earlier
two. Also, motivated by the swing lemma and mechanical pinball games with
flippers, we construct an online game called Swing lattice game. A computer
program realizing this game is available from the authors' websites.


title:
Another one grinds the dust: Variability of the planetary debris disc at
  the white dwarf SDSS J104341.53+085558.2

abstract:
  We report nine years of optical spectroscopy of the metal-polluted white
dwarf SDSS J104341.53+085558.2, which presents morphological variations of the
line profiles of the 8600 \AA\ Ca II triplet emission from the gaseous
component of its debris disc. Similar changes in the shape of the Ca II triplet
have also been observed in two other systems that host a gaseous disc, and are
likely related to the same mechanism. We report the Mg, Si, and Ca abundances
of the debris detected in the photosphere of SDSS J1043+0855, place upper
limits on O and Fe, and derive an accretion rate of (2.5 - 12)x$10^8$ g/s,
consistent with those found in other systems with detected debris discs. The
Mg/Si ratio and the upper limit on the Fe/Si ratio of the accreted material
broadly agree with those found for the crust of the Earth. We also review the
range of variability observed among white dwarfs with planetary debris discs.


title:
Infrared High-Resolution Integrated Light Spectral Analyses of M31
  Globular Clusters from APOGEE

abstract:
  Chemical abundances are presented for 25 M31 globular clusters (GCs), based
on moderately high resolution (R = 22, 500) H-band integrated light spectra
from the Apache Point Observatory Galactic Evolution Experiment (APOGEE).
Infrared spectra offer lines from new elements, of different strengths, and at
higher excitation potentials compared to the optical. Integrated abundances of
C, N, and O are derived from CO, CN, and OH molecular features, while Fe, Na,
Mg, Al, Si, K, Ca, and Ti abundances are derived from atomic features. These
abundances are compared to previous results from the optical, demonstrating the
validity and value of infrared integrated light analyses. The CNO abundances
are consistent with typical tip of the red giant branch stellar abundances, but
are systematically offset from optical, Lick index abundances. With a few
exceptions, the other abundances agree between the optical and the infrared
within the 1{\sigma} uncertainties. The first integrated K abundances are also
presented, and demonstrate that K tracks the alpha-elements. The combination of
infrared and optical abundances allows better determinations of GC properties,
and enables probes of the multiple populations in extragalactic GCs. In
particular, the integrated effects of the Na/O anticorrelation can be directly
examined for the first time.


title: Delta(54) flavor phenomenology and strings

abstract:
  Delta(54) can serve as a flavor symmetry in particle physics, but remains
almost unexplored. We show that in a classification of semi-realistic Z3xZ3
heterotic string orbifolds, Delta(54) turns out to be the most natural flavor
symmetry, providing additional motivation for its study. We revisit its
phenomenological potential from a low-energy perspective and subject to the
constraints of string models. We find a model with Delta(54) arising from
heterotic orbifolds that leads to the Gatto-Sartori-Tonin relation for quarks
and charged-leptons. Additionally, in the neutrino sector, it leads to a normal
hierarchy for neutrino masses and a correlation between the reactor and the
atmospheric mixing angles, the latter taking values in the second octant and
being compatible at three sigmas with experimental data.


title: The String Soundscape at Gravitational Wave Detectors

abstract:
  We argue that gravitational wave (GW) signals due to collisions of
ultra-relativistic bubble walls may be common in string theory. This occurs due
to a process of post-inflationary vacuum decay via quantum tunnelling within
(Randall-Sundrum-like) warped throats. Though a specific example is studied in
the context of type IIB string theory, we argue that our conclusions are likely
more general. Many such transitions could have occurred in the
post-inflationary Universe, as a large number of throats with exponentially
different IR scales can be present in the string landscape, potentially leading
to several signals of widely different frequencies -- a soundscape connected to
the landscape of vacua. Detectors such as eLISA and AEGIS, and observations
with BBO, SKA and EPTA (pulsar timing) have the sensitivity to detect such
signals, while at higher frequency aLIGO is not yet at the required
sensitivity. A distribution of primordial black holes is also a likely
consequence, though reliable estimates of masses and $\Omega_{\rm pBH} h^2$
require dedicated numerical simulations, as do the fine details of the GW
spectrum due to the unusual nature of both the bubble walls and transition.


title: Can Gravitational Instantons Really Constrain Axion Inflation?

abstract:
  Axions play a central role in inflationary model building and other
cosmological applications. This is mainly due to their flat potential, which is
protected by a global shift symmetry. However, quantum gravity is known to
break global symmetries, the crucial effect in the present context being
gravitational instantons or Giddings-Strominger wormholes. We attempt to
quantify, as model-independently as possible, how large a scalar potential is
induced by this general quantum gravity effect. We pay particular attention to
the crucial issue which solutions can or cannot be trusted in the presence of a
moduli-stabilisation and a Kaluza-Klein scale. An important conclusion is that,
due to specific numerical prefactors, the effect is surprisingly small even in
UV-completions with the highest possible scale offered by string theory.
  As we go along, we discuss in detail Euclidean wormholes, cored and extremal
instantons, and how the latter arise from 5d Reissner-Nordstrom black holes. We
attempt to dispel possible doubts that wormholes contribute to the scalar
potential by an explicit calculation. We analyse the role of stabilised
dilaton-like moduli. Finally, we argue that Euclidean wormholes may be the
objects satisfying the Weak Gravity Conjecture extended to instantons.


title: Light dark matter scattering in outer neutron star crusts

abstract:
  We calculate for the first time the phonon excitation rate in the outer crust
of a neutron star due to scattering from light dark matter (LDM) particles
gravitationally boosted into the star. We consider dark matter particles in the
sub-GeV mass range scattering off a periodic array of nuclei through an
effective scalar-vector interaction with nucleons. We find that LDM effects
cause a modification of the net number of phonons in the lattice as compared to
the standard thermal result. In addition, we estimate the contribution of LDM
to the ion-ion thermal conductivity in the outer crust and find that it can be
significantly enhanced at large densities. Our results imply that for
magnetized neutron stars the LDM-enhanced global conductivity in the outer
crust will tend to reduce the anisotropic heat conduction between perpendicular
and parallel directions to the magnetic field.


title: Chemical enrichment of the pre-solar cloud by supernova dust grains

abstract:
  The presence of short-lived radioisotopes (SLRs) in solar system meteorites
has been interpreted as evidence that the solar system was exposed to a
supernova shortly before or during its formation. Yet results from
hydrodynamical models of SLR injection into the proto-solar cloud or disc
suggest that gas-phase mixing may not be efficient enough to reproduce the
observed abundances. As an alternative, we explore the injection of SLRs via
dust grains as a way to overcome the mixing barrier. We numerically model the
interaction of a supernova remnant containing SLR-rich dust grains with a
nearby molecular cloud. The dust grains are subject to drag forces and both
thermal and non-thermal sputtering. We confirm that the expanding gas shell
stalls upon impact with the dense cloud and that gas-phase SLR injection occurs
slowly due to hydrodynamical instabilities at the cloud surface. In contrast,
dust grains of sufficient size (> 1 micron) decouple from the gas and penetrate
into the cloud within 0.1 Myr. Once inside the cloud, the dust grains are
destroyed by sputtering, releasing SLRs and rapidly enriching the dense
(potentially star-forming) regions. Our results suggest that SLR transport on
dust grains is a viable mechanism to explain SLR enrichment.


title: Holographic quenches and anomalous transport

abstract:
  We study the response of the chiral magnetic effect due to continuous
quenches induced by time dependent electric fields within holography.
Concretely, we consider a holographic model with dual chiral anomaly and
compute the electric current parallel to a constant, homogeneous magnetic field
and a time dependent electric field in the probe approximation. We explicitly
solve the PDEs by means of pseudospectral methods in spatial and time
directions and study the transition to an universal "fast" quench response.
Moreover, we compute the amplitudes, i.e.,~residues of the quasi normal modes,
by solving the (ODE) Laplace transformed equations. We investigate the
possibility of considering the asymptotic growth rate of the amplitudes as a
well defined notion of initial time scale for linearized systems. Finally, we
highlight the existence of Landau level resonances in the electrical
conductivity parallel to a magnetic field at finite frequency and show
explicitly that these only appear in presence of the anomaly. We show that the
existence of these resonances induces, among others, a long-lived AC electric
current once the electric field is switched off.


title:
A synthetic model of the gravitational wave background from evolving
  binary compact objects

abstract:
  Modeling the stochastic gravitational wave background from various
astrophysical sources is a key objective in view of upcoming observations with
ground- and space-based gravitational wave observatories such as Advanced LIGO,
VIRGO, eLISA and PTA. We develop a synthetic model framework that follows the
evolution of single and binary compact objects in an astrophysical context. We
describe the formation and merger rates of binaries, the evolution of their
orbital parameters with time and the spectrum of emitted gravitational waves at
different stages of binary evolution. Our approach is modular and allows us to
test and constrain different ingredients of the model, including stellar
evolution, black hole formation scenarios and the properties of binary systems.
We use this framework in the context of a particularly well-motivated
astrophysical setup to calculate the gravitational wave background from several
types of sources, including inspiraling stellar-mass binary black holes that
have not merged during a Hubble time. We find that this signal, albeit weak,
has a characteristic shape that can help constrain the properties of binary
black holes in a way complementary to observations of the background from
merger events. We discuss possible applications of our framework in the context
of other gravitational wave sources, such as supermassive black holes.


title:
Social Politics: Agenda Setting and Political Communication on Social
  Media

abstract:
  Social media play an increasingly important role in political communication.
Various studies investigated how individuals adopt social media for political
discussion, to share their views about politics and policy, or to mobilize and
protest against social issues. Yet, little attention has been devoted to the
main actors of political discussions: the politicians. In this paper, we
explore the topics of discussion of U.S. President Obama and the 50 U.S. State
Governors using Twitter data and agenda-setting theory as a tool to describe
the patterns of daily political discussion, uncovering the main topics of
attention and interest of these actors. We examine over one hundred thousand
tweets produced by these politicians and identify seven macro-topics of
conversation, finding that Twitter represents a particularly appealing vehicle
of conversation for American opposition politicians. We highlight the main
motifs of political conversation of the two parties, discovering that
Republican and Democrat Governors are more or less similarly active on Twitter
but exhibit different styles of communication. Finally, by reconstructing the
networks of occurrences of Governors' hashtags and keywords related to
political issues, we observe that Republicans form a tight core, with a
stronger shared agenda on many issues of discussion.


title:
A Direct Measurement of the High-Mass End of the Velocity Dispersion
  Function at $z\sim0.55$ from SDSS-III/BOSS

abstract:
  We report the first direct spectroscopic measurement of the velocity
dispersion function (VDF) for the high-mass red sequence (RS) galaxy population
at redshift $z\sim0.55$. We achieve high precision by using a sample of 600,000
massive galaxies with spectra from the Baryon Oscillation Spectroscopic Survey
(BOSS) of the third Sloan Digital Sky Survey (SDSS-III), covering stellar
masses $M_*\gtrsim10^{11}~M_{\odot}$. We determine the VDF by projecting the
joint probability-density function (PDF) of luminosity $L$ and velocity
dispersion $\sigma$, i.e. $p(L,\sigma)$, defined by our previous measurements
of the RS luminosity function and $L-\sigma$ relation for this sample. These
measurements were corrected from red--blue galaxy population confusion,
photometric blurring, incompleteness and selection effects within a
forward-modeling framework that furthermore correctly accommodates the low
spectroscopic signal-to-noise ratio of individual BOSS spectra. Our $z\sim0.55$
RS VDF is in overall agreement with the $z\sim0$ early-type galaxy (ETG) VDF at
$\log_{10}\sigma\gtrsim2.47$, however the number density of $z=0.55$ RS
galaxies that we report is larger than that of $z=0$ ETG galaxies at
$2.35\gtrsim\log_{10}\sigma\gtrsim 2.47$. The extrapolation of an
intermediate-mass L-$\sigma$ relation towards the high-mass end in previous
low-z works may be responsible for this disagreement. Evolutionary
interpretation of this comparison is also subject to differences in the way the
respective samples are selected; these differences can be mitigated in future
work by analyzing $z=0$ SDSS data using the same framework presented in this
paper. We also provide the sample PDF for the RS population (i.e. uncorrected
for incompleteness), which is a key ingredient for gravitational lensing
analyses using BOSS.


title: Nnaturalness

abstract:
  We present a new solution to the electroweak hierarchy problem. We introduce
$N$ copies of the Standard Model with varying values of the Higgs mass
parameter. This generically yields a sector whose weak scale is parametrically
removed from the cutoff by a factor of $1/\sqrt{N}$. Ensuring that reheating
deposits a majority of the total energy density into this lightest sector
requires a modification of the standard cosmological history, providing a
powerful probe of the mechanism. Current and near-future experiments will
explore much of the natural parameter space. Furthermore, supersymmetric
completions which preserve grand unification predict superpartners with mass
below $m_W \times M_{\text{pl}} / M_{\text{GUT}} \sim 10$ TeV.


title: Minimal models for nonreciprocal amplification using biharmonic drives

abstract:
  We present a generic system of three harmonic modes coupled parametrically
with a time-varying coupling modulated by a combination of two pump harmonics,
and show how this system provides the minimal platform to realize nonreciprocal
couplings that can lead to gainless photon circulation, and phase-preserving or
phase-sensitive directional amplification. Explicit frequency-dependent
calculations within this minimal paradigm highlight the separation of
amplification and directionality bandwidths, universal in such schemes. We also
study the influence of counter-rotating interactions that can adversely affect
directionality and associated bandwidth; we find that these effects can be
mitigated by suitably designing the properties of the auxiliary mode that plays
the role of an engineered reservoir to the amplification mode space.


title:
Measurement of the ratio of branching fractions $\mathcal{B}(B_{c}^{+}
  \to J/\psi K^{+})/\mathcal{B}(B_{c}^{+} \to J/\psi\pi^{+})$

abstract:
  The ratio of branching fractions $R_{K/\pi} \equiv \mathcal{B}(B_{c}^{+} \to
J/\psi K^{+})/\mathcal{B}(B_{c}^{+} \to J/\psi\pi^{+})$ is measured with $pp$
collision data collected by the LHCb experiment at centre-of-mass energies of 7
TeV and 8 TeV, corresponding to an integrated luminosity of
3${\mbox{fb}^{-1}}$. It is found to be $ R_{K/\pi} = 0.079\pm0.007\pm0.003$,
where the first uncertainty is statistical and the second is systematic. This
measurement is consistent with the previous LHCb result, while the
uncertainties are significantly reduced.


title:
Permutation, Multiscale and Modified Multiscale Entropies a Natural
  Complexity for Low-High Infection Level Intracellular Viral Reaction Kinetics

abstract:
  Viral infectious diseases, such as HIV virus growth, cause an important
health concern. Study of intracellular viral processes can provide us to
develop drug and understanding the drug dose to decrease the HIV virus in
during growth. Kinetics Monte Carlo simulation has been done for solving Master
equation about dynamics of intracellular viral reaction kinetics. Scaling
relationship between equilibrium time and initial population of template has
been found as power low, , where N , are the number of initial population of
template species , equilibrium time, a = 163.1 , b = -0.1429 respectively.
Stochastic dynamics shows that increasing initial population of template
decreases the time of equilibrium. Entropy generation has been considered in
low, intermediate and high infection level of intracellular viral kinetics
reaction in during dynamical process. Permutation, multi scaling and modified
multiscaling entropies have been calculated for three kinds of species in
intracellular reaction dynamics, genome, structural protein, and template. Our
result shows that presence of noise in dynamical process of intracellular
reaction will change order of permutation entropy for the mentioned of three
species. In addition to multiscaling entropy is computed for mentioned model
and it has the following order: template > structural protein> genome.
Dependency of permutation entropy result to permutation order becomes small in
high infection level in intracellular viral kinetics dynamics. At short time
scale in intracellular reaction dynamics, convergency of permutation entropy
occurs with medium permutation order value. In the big time scale of
intracellular dynamics, permutation entropy scale with permutation order n as a
scaling relation .


title: High sensitivity to mass-ratio variation in deep molecular potentials

abstract:
  Molecular vibrational transitions are prime candidates for model-independent
searches for variation of the proton-to-electron mass ratio. Searches for
present-day variation achieve highest sensitivity with deep molecular
potentials. We identify several high-sensitivity transitions in the deeply
bound ${\rm O}_2^+$ molecular ion. These transitions are electric-dipole
forbidden and thus have narrow linewidths. The most sensitive transitions take
advantage of an accidental degeneracy between vibrational states in different
electronic potentials. We suggest experimentally feasible routes to a
measurement with uncertainty exceeding current limits on present-day variation
in $m_p/m_e$.


title: Hadron Correlations at Energies from GeV to TeV

abstract:
  One of the central issues in High Energy Physics is the close interchange
between Theory and Experiment. Ever since I know Andrzej Bia{\l}as, I know him
as one of the theorists most interested in experimental data. This has
naturally led to continuous fruitful contacts. Even though we have been working
somehow together since about 1968, we so far have only one single publication
in common. This was back in 1969 and it was on means to efficiently study what
we then called (exclusive) Multihadron Final States. At that time this meant 3-
or at best 4-particle final states of two-hadron collisions at cms energies of
some 4 GeV (not TeV!). The field of multiparticle dynamics was in fact the
domain of Polish high-energy physicists. The first of a very successful (and
still lasting) series of annual International Symposia on Multiparticle
Dynamics was organized in Paris in 1970, but essentially by Polish physicists.
Andrzej himself was not attending, but it was he who organized the third in
these series in (of course) Zakopane. Since heavy ion-collisions, another field
of major interest for Andrzej, will be covered by others, I here will restrict
myself mainly to the collisions of two elementary particles.


title: Effective Theories of Flavor and the Non-Universal MSSM

abstract:
  Flavor symmetries \`{a} la Froggatt-Nielsen~(FN) provide a compelling way to
explain the hierarchies of fermionic masses and mixing angles in the Yukawa
sector. In Supersymmetric~(SUSY) extensions of the Standard Model where the
mediation of SUSY breaking occurs at scales larger than the breaking of flavor,
this symmetry must be respected not only by the Yukawas of the superpotential,
but by the soft-breaking masses and trilinear terms as well. In this work we
show that contrary to naive expectations, even starting with completely flavor
blind soft-breaking in the full theory at high scales, the low-energy sfermion
mass matrices and trilinear terms of the effective theory, obtained upon
integrating out the heavy mediator fields, are strongly non-universal. We
explore the phenomenology of these SUSY flavor models after the latest LHC
searches for new physics.


title: Instability of supersymmetric microstate geometries

abstract:
  We investigate the classical stability of supersymmetric, asymptotically
flat, microstate geometries with five non-compact dimensions. Such geometries
admit an "evanescent ergosurface": a timelike hypersurface of infinite
redshift. On such a surface, there are null geodesics with zero energy relative
to infinity. These geodesics are stably trapped in the potential well near the
ergosurface. We present a heuristic argument indicating that this feature is
likely to lead to a nonlinear instability of these solutions. We argue that the
precursor of such an instability can be seen in the behaviour of linear
perturbations: nonlinear stability would require that all linear perturbations
decay sufficiently rapidly but the stable trapping implies that some linear
perturbation decay very slowly. We study this in detail for the most symmetric
microstate geometries. By constructing quasinormal modes of these geometries we
show that generic linear perturbations decay slower than any inverse power of
time.


title:
A perturbation study of axisymmetric strongly magnetic degenerate stars
  : the case of super-Chandrasekhar white dwarfs

abstract:
  In the presence of a strong magnetic field a stellar equilibrium
configuration, aided by the Lorentz force, can support a larger mass than a
non-magnetic one. This has been considered a possible explanation of the
super-Chandrasekhar mass white dwarfs giving rise to over-luminous Type-Ia
supernovae. We present here linear and non-linear perturbation studies of such
strongly magetised configurations and show that axisymmetric configurations
with poloidal or toroidal fields are unstable. The numerical evolution of the
perturbations shows instability after about an Alfv\'en crossing time. This
time scale is very short for the magnetically supported super-Chandrasekhar
mass white dwarfs. Uniform rotation about the symmetry axis can reduce the
growth rate but can not stabilize the super-massive configurations. It is
concluded that long-lived super-Chandrasekhar mass white dwarfs supported by
magnetic field are unlikely to occur in Nature.


title:
iDRM: Humanoid Motion Planning with Real-Time End-Pose Selection in
  Complex Environments

abstract:
  In this paper, we propose a novel inverse Dynamic Reachability Map (iDRM)
that allows a floating base system to find valid end-poses in complex and
dynamically changing environments in real-time. End-pose planning for valid
stance pose and collision-free configuration is an essential problem for
humanoid applications, such as providing goal states for walking and motion
planners. However, this is non-trivial in complex environments, where standing
locations and reaching postures are restricted by obstacles. Our proposed iDRM
customizes the robot-to-workspace occupation list and uses an online update
algorithm to enable efficient reconstruction of the reachability map to
guarantee that the selected end-poses are always collision-free. The iDRM was
evaluated in a variety of reaching tasks using the 38 degree-of-freedom (DoF)
humanoid robot Valkyrie. Our results show that the approach is capable of
finding valid end-poses in a fraction of a second. Significantly, we also
demonstrate that motion planning algorithms integrating our end-pose planning
method are more efficient than those not utilizing this technique.


title: Improving broadband displacement detection with quantum correlations

abstract:
  Interferometers enable ultrasensitive measurement in a wide array of
applications from gravitational wave searches to force microscopes. The role of
quantum mechanics in the metrological limits of interferometers has a rich
history, and a large number of techniques to surpass conventional limits have
been proposed. In a typical measurement configuration, the tradeoff between the
probe's shot noise (imprecision) and its quantum backaction results in what is
known as the standard quantum limit (SQL). In this work we investigate how
quantum correlations accessed by modifying the readout of the interferometer
can access physics beyond the SQL and improve displacement sensitivity.
Specifically, we use an optical cavity to probe the motion of a silicon nitride
membrane off mechanical resonance, as one would do in a broadband displacement
or force measurement, and observe sensitivity better than the SQL dictates for
our quantum efficiency. Our measurement illustrates the core idea behind a
technique known as \textit{variational readout}, in which the optical readout
quadrature is changed as a function of frequency to improve broadband
displacement detection. And more generally our result is a salient example of
how correlations can aid sensing in the presence of backaction.


title:
Lepton flavor violating Z' explanation of the muon anomalous magnetic
  moment

abstract:
  We discuss a minimal solution to the long-standing $(g-2)_\mu$ anomaly in a
simple extension of the Standard Model with an extra $Z'$ vector boson that has
only flavor off-diagonal couplings to the second and third generation of
leptons, i.e. $\mu, \tau, \nu_\mu, \nu_\tau$ and their antiparticles. A
simplified model realization, as well as various collider and low-energy
constraints on this model, are discussed. We find that the $(g-2)_\mu$-favored
region for a $Z'$ lighter than the tau lepton is totally excluded, while a
heavier $Z'$ solution is still allowed. Some testable implications of this
scenario in future experiments, such as lepton-flavor universality-violating
tau decays at Belle 2, and a new four-lepton signature involving same-sign
di-muons and di-taus at HL-LHC and FCC-ee, are pointed out. A characteristic
resonant absorption feature in the high-energy neutrino spectrum might also be
observed by neutrino telescopes like IceCube and KM3NeT.


title:
Explicit Polyhedral Bounds on Network Coding Rate Regions via Entropy
  Function Region: Algorithms, Symmetry, and Computation

abstract:
  Automating the solutions of multiple network information theory problems,
stretching from fundamental concerns such as determining all information
inequalities and the limitations of linear codes, to applied ones such as
designing coded networks, distributed storage systems, and caching systems, can
be posed as polyhedral projections. These problems are demonstrated to exhibit
multiple types of polyhedral symmetries. It is shown how these symmetries can
be exploited to reduce the complexity of solving these problems through
polyhedral projection.


title:
A Numerical Investigation of Matrix-Free Implicit Time-Stepping Methods
  for Large CFD Simulations

abstract:
  This paper is concerned with the development and testing of advanced
time-stepping methods suited for the integration of time-accurate, real-world
applications of computational fluid dynamics (CFD). The performance of several
time discretization methods is studied numerically with regards to
computational efficiency, order of accuracy, and stability, as well as the
ability to treat effectively stiff problems. We consider matrix-free
implementations, a popular approach for time-stepping methods applied to large
CFD applications due to its adherence to scalable matrix-vector operations and
a small memory footprint. We compare explicit methods with matrix-free
implementations of implicit, linearly-implicit, as well as Rosenbrock-Krylov
methods. We show that Rosenbrock-Krylov methods are competitive with existing
techniques excelling for a number of problem types and settings.


title: Minimal Immunogenic Epitopes Have Nine Amino Acids

abstract:
  To be cost-effective, biomedical proteins must be optimized with regard to
many factors. Road maps are customary for large-scale projects, and here
descriptive methods based on bioinformatic fractal thermodynamic scales are
tested against an important example, HPV vaccine. Older scales from before 2000
are found to yield inconclusive results, but modern bioinformatic scales are
amazingly accurate, with a high level of internal consistency, and little
ambiguity.


title: Allosteric Regulation by a Critical Membrane

abstract:
  Many of the processes that underly neural computation are carried out by ion
channels embedded in the plasma membrane, a two-dimensional liquid that
surrounds all cells. Recent experiments have demonstrated that this membrane is
poised close to a liquid-liquid critical point in the Ising universality class.
Here we use both exact and stochastic techniques on the lattice Ising model to
explore the ramifications of proximity to criticality for proteins that are
allosterically coupled to Ising composition modes. Owing to diverging
generalized susceptibilities, such a protein's activity becomes strongly
influenced by perturbations that influence the two relevant parameters of the
critical point, especially the critical temperature. In addition, the protein's
kinetics acquire a range of time scales from its surrounding membrane,
naturally leading to non-Markovian dynamics.

categories: physics.bio-ph cond-mat.soft cond-mat.stat-mech q-bio.SC


title:
Nonasymptotic coding-rate bounds for binary erasure channels with
  feedback

abstract:
  We present nonasymptotic achievability and converse bounds on the maximum
coding rate (for a fixed average error probability and a fixed average
blocklength) of variable-length full-feedback (VLF) and variable-length
stop-feedback (VLSF) codes operating over a binary erasure channel (BEC). For
the VLF setup, the achievability bound relies on a scheme that maps each
message onto a variable-length Huffman codeword and then repeats each bit of
the codeword until it is received correctly. The converse bound is inspired by
the meta-converse framework by Polyanskiy, Poor, and Verd\'u (2010) and relies
on binary sequential hypothesis testing. For the case of zero error
probability, our achievability and converse bounds match. For the VLSF case, we
provide achievability bounds that exploit the following feature of BEC: the
decoder can assess the correctness of its estimate by verifying whether the
chosen codeword is the only one that is compatible with the erasure pattern.
One of these bounds is obtained by analyzing the performance of a
variable-length extension of random linear fountain codes. The gap between the
VLSF achievability and the VLF converse bound, when number of messages is
small, is significant: $23\%$ for 8 messages on a BEC with erasure probability
$0.5.$ The absence of a tight VLSF converse bound does not allow us to assess
whether this gap is fundamental.


title: Transport-induced inversion of screening ionic charges in nanochannels

abstract:
  This work reveals a counter-intuitive but basic process of ionic screening in
nano-fluidic channels. Steady-state numerical simulations and mathematical
analysis show that, under significant longitudinal ionic transport, the
screening ionic charges can be locally inverted in the channels: their charge
sign becomes the same as that of the channel surface charges. The process is
identified to originate from the coupling of ionic electro-diffusion transport
and junction 2-D electrostatics. This finding may expand our understanding on
ionic screening and electrical double layers in nano-channels. Furthermore, the
charge inversion process results in a body-force torque on channel fluids,
which is a possible mechanism for vortex generation in the channels and their
nonlinear current-voltage characteristics.


title: How to Succeed in Crowdfunding: a Long-Term Study in Kickstarter

abstract:
  Crowdfunding platforms have become important sites where people can create
projects to seek funds toward turning their ideas into products, and back
someone else's projects. As news media have reported successfully funded
projects (e.g., Pebble Time, Coolest Cooler), more people have joined
crowdfunding platforms and launched projects. But in spite of rapid growth of
the number of users and projects, a project success rate at large has been
decreasing because of launching projects without enough preparation and
experience. Little is known about what reactions project creators made (e.g.,
giving up or making the failed projects better) when projects failed, and what
types of successful projects we can find. To solve these problems, in this
manuscript we (i) collect the largest datasets from Kickstarter, consisting of
all project profiles, corresponding user profiles, projects' temporal data and
users' social media information; (ii) analyze characteristics of successful
projects, behaviors of users and understand dynamics of the crowdfunding
platform; (iii) propose novel statistical approaches to predict whether a
project will be successful and a range of expected pledged money of the
project; (iv) develop predictive models and evaluate performance of the models;
(v) analyze what reactions project creators had when project failed, and if
they did not give up, how they made the failed projects successful; and (vi)
cluster successful projects by their evolutional patterns of pledged money
toward understanding what efforts project creators should make in order to get
more pledged money. Our experimental results show that the predictive models
can effectively predict project success and a range of expected pledged money.


title:
Young stars and ionized nebulae in M83: comparing chemical abundances at
  high metallicity

abstract:
  We present spectra of 14 A-type supergiants in the metal-rich spiral galaxy
M83. We derive stellar parameters and metallicities, and measure a
spectroscopic distance modulus m-M = 28.47 +\- 0.10 (4.9 +\- 0.2 Mpc), in
agreement with other methods. We use the stellar characteristic metallicity of
M83 and other systems to discuss a version of the galaxy mass-metallicity
relation that is independent of the analysis of nebular emission lines and the
associated systematic uncertainties. We reproduce the radial metallicity
gradient of M83, which flattens at large radii, with a chemical evolution
model, constraining gas inflow and outflow processes. We carry out a
comparative analysis of the metallicities we derive from the stellar spectra
and published HII region line fluxes, utilizing both the direct, Te-based
method and different strong-line abundance diagnostics. The direct abundances
are in relatively good agreement with the stellar metallicities, once we apply
a modest correction to the nebular oxygen abundance due to depletion onto dust.
Popular empirically calibrated strong-line diagnostics tend to provide nebular
abundances that underestimate the stellar metallicities above the solar value
by ~0.2 dex. This result could be related to difficulties in selecting
calibration samples at high metallicity. The O3N2 method calibrated by Pettini
and Pagel gives the best agreement with our stellar metallicities. We confirm
that metal recombination lines yield nebular abundances that agree with the
stellar abundances for high metallicity systems, but find evidence that in more
metal-poor environments they tend to underestimate the stellar metallicities by
a significant amount, opposite to the behavior of the direct method.


title:
Time-series Doppler imaging of the red giant HD 208472. Active
  longitudes and differential rotation

abstract:
  HD 208472 is among the most active RS~CVn binaries with cool starspots.
Decade-long photometry has shown that the spots seem to change their
longitudinal appearance with a period of about six years, coherent with
brightness variations. Our aim is to spatially resolve the stellar surface of
HD 208472 and relate the photometric results to the true longitudinal and
latitudinal spot appearance. Furthermore, we investigate the surface
differential rotation pattern of the star. We employed three years of
high-resolution spectroscopic data with a high signal-to-noise ratio (S/N) from
the STELLA robotic observatory and determined new and more precise stellar
physical parameters. Precalculated synthetic spectra were fit to each of these
spectra, and we provide new spot-corrected orbital elements. A sample of 34
absorption lines per spectrum was used to calculate mean line profiles with a
S/N of several hundred. A total of 13 temperature Doppler images were
reconstructed from these line profiles with the inversion code iMap.
Differential rotation was investigated by cross-correlating successive Doppler
images in each observing season. Spots on HD 208472 are distributed preferably
at high latitudes and less frequently around mid-to-low latitudes. No polar-cap
like structure is seen at any epoch. We observed a flip-flop event between 2009
and 2010, manifested as a flip of the spot activity from phase 0.0 to phase
0.5, while the overall brightness of the star continued to increase and reached
an all-time maximum in 2014. Cross-correlation of successive Doppler images
suggests a solar-like differential rotation that is ~15 times weaker than that
of the Sun.


title: Rare-Region Onset of Superconductivity in Granular Systems

abstract:
  The critical behavior of disordered systems-from metals (1) to magnets (2)
and superconductors (3)-is often dominated by the behavior of rare regions of a
correlated phase, which control the inception and dynamics of the phase
transition. Yet, despite significant theoretical (3,4,5) and experimental
(6,7,8,9) interest, there has been little direct evidence of the presence of
these regions, or of their role in initiating transitions. Here, we provide
direct evidence for rare-region effects at the onset of superconductivity in
granular superconducting islands. By considering the strong diameter-dependence
of the transition, as well as observations of large fluctuations in the
transition temperature as island diameters decrease, we are able to show that
superconducting order first appears in unusually large grains- i.e. rare
regions- within each island and, due to proximity coupling, spreads to other
grains. This work thus provides a quantitative, local understanding of the
onset of correlated order in strongly disordered systems.


title: High dimension and symmetries in quantum information theory

abstract:
  If a one-phrase summary of the subject of this thesis were required, it would
be something like: miscellaneous large (but finite) dimensional phenomena in
quantum information theory. That said, it could nonetheless be helpful to
briefly elaborate. Starting from the observation that quantum physics
unavoidably has to deal with high dimensional objects, basically two routes can
be taken: either try and reduce their study to that of lower dimensional ones,
or try and understand what kind of universal properties might precisely emerge
in this regime. We actually do not choose which of these two attitudes to
follow here, and rather oscillate between one and the other. In the first part
of this manuscript, our aim is to reduce as much as possible the complexity of
certain quantum processes, while of course still preserving their essential
characteristics. The two types of processes we are interested in are quantum
channels and quantum measurements. Oppositely, the second part of this
manuscript is specifically dedicated to the analysis of high dimensional
quantum systems and some of their typical features. Stress is put on
multipartite systems and on entanglement-related properties of theirs. In the
third part of this manuscript we eventually come back to a more dimensionality
reduction state of mind. This time though, the strategy is to make use of the
symmetries inherent to each particular situation we are looking at in order to
derive a problem-dependent simplification.


title:
From the Komar Mass and Entropic Force Scenarios to the Einstein Field
  Equations on the Ads Brane

abstract:
  By bearing the Komar's definition for the mass, together with the entropic
origin of gravity in mind, we find the Einstein field equations in
$(n+1$)-dimensional spacetime. Then, by reflecting the ($4+1$)-dimensional
Einstein equations on the ($3+1$)-hypersurface, we get the Einstein equations
onto the $3$-brane. The corresponding energy conditions are also addressed.
Since the higher dimensional considerations modify the Einstein field equations
in the ($3+1$)-dimensions and thus the energy-momentum tensor, we get a
relation for the Komar mass on the brane. In addition, the strongness of this
relation compared with existing definition for the Komar mass on the brane is
addressed.


title: A statistical mechanics approach to mixing in stratified fluids

abstract:
  Predicting how much mixing occurs when a given amount of energy is injected
into a Boussinesq fluid is a longstanding problem in stratified turbulence. The
huge number of degrees of freedom involved in those processes renders extremely
difficult a deterministic approach to the problem. Here we present a
statistical mechanics approach yielding prediction for a cumulative, global
mixing efficiency as a function of a global Richardson number and the
background buoyancy profile.


title:
Singularities of axially symmetric time-like minimal submanifolds in
  Minkowski space

abstract:
  We prove that there does not exist global-in-time axisymmetric solutions to
the time-like minimal submanifold system in Minkowski space. We further analyze
the limiting geometry as the maximal time of existence is approached.


title:
Decentralized Bayesian learning in dynamic games: A framework for
  studying informational cascades

abstract:
  We study the problem of Bayesian learning in a dynamical system involving
strategic agents with asymmetric information. In a series of seminal papers in
the literature, this problem has been investigated under a simplifying model
where myopically selfish players appear sequentially and act once in the game,
based on private noisy observations of the system state and public observation
of past players' actions. It has been shown that there exist information
cascades where users discard their private information and mimic the action of
their predecessor. In this paper, we provide a framework for studying Bayesian
learning dynamics in a more general setting than the one described above. In
particular, our model incorporates cases where players are non-myopic and
strategically participate for the whole duration of the game, and cases where
an endogenous process selects which subset of players will act at each time
instance. The proposed framework hinges on a sequential decomposition
methodology for finding structured perfect Bayesian equilibria (PBE) of a
general class of dynamic games with asymmetric information, where user-specific
states evolve as conditionally independent Markov processes and users make
independent noisy observations of their states. Using this methodology, we
study a specific dynamic learning model where players make decisions about
public investment based on their estimates of everyone's types. We characterize
a set of informational cascades for this problem where learning stops for the
team as a whole. We show that in such cascades, all players' estimates of other
players' types freeze even though each individual player asymptotically learns
its own true type.


title: Eigenvalues of Robin Laplacians in infinite sectors

abstract:
  For $\alpha\in(0,\pi)$, let $U_\alpha$ denote the infinite planar sector of
opening $2\alpha$, \[ U_\alpha=\big\{ (x_1,x_2)\in\mathbb R^2:
\big|\arg(x_1+ix_2) \big|<\alpha \big\}, \] and $T^\gamma_\alpha$ be the
Laplacian in $L^2(U_\alpha)$, $T^\gamma_\alpha u= -\Delta u$, with the Robin
boundary condition $\partial_\nu u=\gamma u$, where $\partial_\nu$ stands for
the outer normal derivative and $\gamma>0$. The essential spectrum of
$T^\gamma_\alpha$ does not depend on the angle $\alpha$ and equals
$[-\gamma^2,+\infty)$, and the discrete spectrum is non-empty iff
$\alpha<\frac\pi 2$. In this case we show that the discrete spectrum is always
finite and that each individual eigenvalue is a continous strictly increasing
function of the angle $\alpha$. In particular, there is just one discrete
eigenvalue for $\alpha \ge \frac{\pi}{6}$. As $\alpha$ approaches $0$, the
number of discrete eigenvalues becomes arbitrary large and is minorated by
$\kappa/\alpha$ with a suitable $\kappa>0$, and the $n$th eigenvalue
$E_n(T^\gamma_\alpha)$ of $T^\gamma_\alpha$ behaves as \[
E_n(T^\gamma_\alpha)=-\dfrac{\gamma^2}{(2n-1)^2 \alpha^2}+O(1) \] and admits a
full asymptotic expansion in powers of $\alpha^2$. The eigenfunctions are
exponentially localized near the origin. The results are also applied to
$\delta$-interactions on star graphs.


title:
Reciprocal Graphical Models for Integrative Gene Regulatory Network
  Analysis

abstract:
  Constructing gene regulatory networks is a fundamental task in systems
biology. We introduce a Gaussian reciprocal graphical model for inference about
gene regulatory relationships by integrating mRNA gene expression and DNA level
information including copy number and methylation. Data integration allows for
inference on the directionality of certain regulatory relationships, which
would be otherwise indistinguishable due to Markov equivalence. Efficient
inference is developed based on simultaneous equation models. Bayesian model
selection techniques are adopted to estimate the graph structure. We illustrate
our approach by simulations and two applications in ZODIAC pairwise gene
interaction analysis and colon adenocarcinoma pathway analysis.


title:
Thermodynamic Limit of Crystal Defects with Finite Temperature Tight
  Binding

abstract:
  We consider a tight binding model for localised crystalline defects with
electrons in the canonical ensemble (finite electronic temperature) and nuclei
positions relaxed according to the Born--Oppenheimer approximation. We prove
that the limit model as the computational domain size grows to infinity is
formulated in the grand-canonical ensemble for the electrons. The Fermi-level
for the limit model is fixed at a homogeneous crystal level, independent of the
defect or electron number in the sequence of finite-domain approximations. We
quantify the rates of convergence for the nuclei configuration and for the
Fermi-level.


title:
Biaxial nematic phase stability and demixing behaviour in monolayers of
  rod-plate mixtures

abstract:
  We theoretically study the phase behaviour of monolayers of hard rod-plate
mixtures using a fundamental-measure density functional in the
restricted-orientation (Zwanzig) approximation. We consider both species to be
subject to an attractive potential proportional to the particle contact area on
the surface and with adsorption strengths that depend on the species type.
Particles have board-like shape, with sizes chosen using a symmetry criterion:
same volume and same aspect ratio $\kappa$. Phase diagrams were calculated for
$\kappa=10$, 20 and 40 and different values of adsorption strengths. For small
adsorption strengths the mixtures exhibit a second-order uniaxial
nematic-biaxial nematic transition for molar fraction of rods $0\leq x\lesssim
0.9$. In the uniaxial nematic phase the particle axes of rods and plates are
aligned perpendicular and parallel to the monolayer, respectively. At the
transition, the orientational symmetry of the plate axes is broken, and they
orient parallel to a director lying on the surface. For large and equal
adsorption strengths the mixture demixes at low pressures into a uniaxial
nematic phase, rich in plates, and a biaxial nematic phase, rich in rods. This
demixing is located between two tricritical points. Also, at higher pressures
and in the plate-rich part of the phase diagram, the system exhibits a strong
first-order uniaxial nematic-biaxial nematic phase transition with a large
density coexistence gap. When rod adsorption is considerably large while that
of plates is small, the transition to the biaxial nematic phase is always of
second order. At very high pressures the mixture can effectively be identified
as a two-dimensional mixture of squares and rectangles which again demixes
above a certain critical point. We also studied the relative stability of
uniform phases with respect to density modulations of smectic, columnar and
crystalline symmetry.


title:
CFGs-2-NLU: Sequence-to-Sequence Learning for Mapping Utterances to
  Semantics and Pragmatics

abstract:
  In this paper, we present a novel approach to natural language understanding
that utilizes context-free grammars (CFGs) in conjunction with
sequence-to-sequence (seq2seq) deep learning. Specifically, we take a CFG
authored to generate dialogue for our target application for NLU, a videogame,
and train a long short-term memory (LSTM) recurrent neural network (RNN) to map
the surface utterances that it produces to traces of the grammatical expansions
that yielded them. Critically, this CFG was authored using a tool we have
developed that supports arbitrary annotation of the nonterminal symbols in the
grammar. Because we already annotated the symbols in this grammar for the
semantic and pragmatic considerations that our game's dialogue manager operates
over, we can use the grammatical trace associated with any surface utterance to
infer such information. During gameplay, we translate player utterances into
grammatical traces (using our RNN), collect the mark-up attributed to the
symbols included in that trace, and pass this information to the dialogue
manager, which updates the conversation state accordingly. From an offline
evaluation task, we demonstrate that our trained RNN translates surface
utterances to grammatical traces with great accuracy. To our knowledge, this is
the first usage of seq2seq learning for conversational agents (our game's
characters) who explicitly reason over semantic and pragmatic considerations.


title:
Constraining Anomalous Forces with Pseudoscalar and Axial Couplings
  Employing a Spin-Independent Analysis

abstract:
  Present laboratory limits on the coupling strength of anomalous pseudoscalar
and axial interactions are many orders of magnitude weaker than their scalar
and vector analogs. Here we investigate two mechanisms which can circumvent
this suppression and thereby lead to improved limits.


title:
Unsupervised Learning from Continuous Video in a Scalable Predictive
  Recurrent Network

abstract:
  Understanding visual reality involves acquiring common-sense knowledge about
countless regularities in the visual world, e.g., how illumination alters the
appearance of objects in a scene, and how motion changes their apparent spatial
relationship. These regularities are hard to label for training supervised
machine learning algorithms; consequently, algorithms need to learn these
regularities from the real world in an unsupervised way. We present a novel
network meta-architecture that can learn world dynamics from raw, continuous
video. The components of this network can be implemented using any algorithm
that possesses three key capabilities: prediction of a signal over time,
reduction of signal dimensionality (compression), and the ability to use
supplementary contextual information to inform the prediction. The presented
architecture is highly-parallelized and scalable, and is implemented using
localized connectivity, processing, and learning. We demonstrate an
implementation of this architecture where the components are built from
multi-layer perceptrons. We apply the implementation to create a system capable
of stable and robust visual tracking of objects as seen by a moving camera.
Results show performance on par with or exceeding state-of-the-art tracking
algorithms. The tracker can be trained in either fully supervised or
unsupervised-then-briefly-supervised regimes. Success of the briefly-supervised
regime suggests that the unsupervised portion of the model extracts useful
information about visual reality. The results suggest a new class of AI
algorithms that uniquely combine prediction and scalability in a way that makes
them suitable for learning from and --- and eventually acting within --- the
real world.


title:
Uncovering edge states and electrical inhomogeneity in MoS2 field-effect
  transistors

abstract:
  The understanding of various types of disorders in atomically thin transition
metal dichalcogenides (TMDs), including dangling bonds at the edges, chalcogen
deficiencies in the bulk, and charges in the substrate, is of fundamental
importance for their applications in electronics and photonics. Because of the
imperfections, electrons moving on these two-dimensional (2D) crystals
experience a spatially non-uniform Coulomb environment, whose effect on the
charge transport has not been microscopically studied. Here, we report the
mesoscopic conductance mapping in monolayer and few-layer MoS2 field-effect
transistors (FETs) by microwave impedance microscopy (MIM). The spatial
evolution of the insulator-to-metal transition is clearly resolved.
Interestingly, as the transistors are gradually turned on, electrical
conduction emerges initially at the edges before appearing in the bulk of MoS2
flakes, which can be explained by our first-principles calculations. The
results unambiguously confirm that the contribution of edge states to the
channel conductance is significant under the threshold voltage but negligible
once the bulk of the TMD device becomes conductive. Strong conductance
inhomogeneity, which is associated with the fluctuations of disorder potential
in the 2D sheets, is also observed in the MIM images, providing a guideline for
future improvement of the device performance.


title:
Interaction of Molecular Oxygen with Hexagonally Reconstructed Au (001)
  Surface

abstract:
  Kinetics of molecular oxygen / Au (001) surface interaction has been studied
at high temperature and near atmospheric pressures of O2 gas with in situ x-ray
scattering measurements. We find that the hexagonal reconstruction (hex) of Au
(001) surface lifts to (1x1) in the presence of O2 gas, indicating that the
(1x1) is more favored when some oxygen atoms present on the surface. The
measured lifting rate constant vs. temperature is found to be highest at
intermediate temperature exhibiting a 'volcano'-type behavior. At low
temperature, the hex-to-(1x1) activation barrier (Eact = 1.3(3) eV) limits the
lifting. At high temperature, oxygen adsorption energy (Eads = 1.6(2) eV)
limits the lifting. The (1x1)-to-hex activation barrier (Ehex = 0.41(14) eV) is
also obtained from hex recovery kinetics. The pressure-temperature (PT) surface
phase diagram obtained in this study shows three regions: hex at low P and T,
(1x1) at high P and T, and coexistence of the hex and (1x1) at the intermediate
P and T.


title: Model Checker Execution Reports

abstract:
  Software model checking constitutes an undecidable problem and, as such, even
an ideal tool will in some cases fail to give a conclusive answer. In practice,
software model checkers fail often and usually do not provide any information
on what was effectively checked. The purpose of this work is to provide a
conceptual framing to extend software model checkers in a way that allows users
to access information about incomplete checks. We characterize the information
that model checkers themselves can provide, in terms of analyzed traces, i.e.
sequences of statements, and safe cones, and present the notion of execution
reports, which we also formalize. We instantiate these concepts for a family of
techniques based on Abstract Reachability Trees and implement the approach
using the software model checker CPAchecker. We evaluate our approach
empirically and provide examples to illustrate the execution reports produced
and the information that can be extracted.


title: New observational limits on dark radiation in brane-world cosmology

abstract:
  A dark radiation term arises as a correction to the energy momentum tensor in
the simplest five-dimensional RS-II brane-world cosmology. In this paper we
revisit the constraints on dark radiation based upon the newest results for
light-element nuclear reaction rates, observed light-element abundances and the
power spectrum of the Cosmic Microwave Background (CMB). Adding dark radiation
during big bang nucleosynthesis alters the Friedmann expansion rate causing the
nuclear reactions to freeze out at a different temperature. This changes the
final light element abundances at the end of BBN. Its influence on the CMB is
to change the effective expansion rate at the surface of last scattering. We
find that our adopted BBN constraints reduce the allowed range for dark
radiation to between $-12.1\%$ and $+6.2\%$ of the ambient background energy
density. Combining this result with fits to the CMB power spectrum, the range
decreases to $-6.0\%$ to $+6.2\%$. Thus, we find, that the ratio of dark
radiation to the background total relativistic mass energy density $\rho_{\rm
DR}/\rho$ is consistent with zero although in the BBN analysis there could be a
slight preference for a negative contribution. However, the BBN constraint
depends strongly upon the adopted primordial helium abundance.


title:
Wavelength extension beyond 1.5 micrometer in symmetric InAs quantum
  dots on InP(111)A using droplet epitaxy

abstract:
  By using a C3v symmetric (111) surface as a growth substrate, we are able to
achieve high structural symmetry in self-assembled quantum dots, which are
suitable for use as quantum-entangled photon emitters. Here we report on the
wavelength controllability of InAs dots on InP(111)A, which we realized by
tuning the ternary alloy composition of In(Al,Ga)As barriers that were
lattice-matched to InP. We changed the peak emission wavelength systematically
from 1.3 to 1.7 micrometer by barrier band gap tuning. The observed spectral
shift agreed with the result of numerical simulations that assumed a measured
shape distribution independent of barrier choice.


title:
Multicellular self-organization of P. aeruginosa due to interactions
  with secreted trails

abstract:
  Guided movement in response to slowly diffusing polymeric trails provides a
unique mechanism for self-organization of some microorganisms. To elucidate how
this signaling route leads to microcolony formation, we experimentally probe
the trajectory and orientation of Pseudomonas aeruginosa that propel themselves
on a surface using type IV pili motility appendages, which preferentially
attach to deposited exopolysaccharides. We construct a stochastic model by
analyzing single-bacterium trajectories, and show that the resulting
theoretical prediction for the many-body behavior of the bacteria is in
quantitative agreement with our experimental characterization of how cells
explore the surface via a power law strategy.

categories: q-bio.CB cond-mat.soft physics.bio-ph q-bio.PE


title: BICEP3 focal plane design and detector performance

abstract:
  BICEP3, the latest telescope in the BICEP/Keck program, started science
observations in March 2016. It is a 550mm aperture refractive telescope
observing the polarization of the cosmic microwave background at 95 GHz. We
show the focal plane design and detector performance, including spectral
response, optical efficiency and preliminary sensitivity of the upgraded
BICEP3. We demonstrate 9.72$\mu$K$\sqrt{\textrm{s}}$ noise performance of the
BICEP3 receiver.


title:
Global Weak Rigidity of the Gauss-Codazzi-Ricci Equations and Isometric
  Immersions of Riemannian Manifolds with Lower Regularity

abstract:
  We are concerned with the global weak rigidity of the Gauss-Codazzi-Ricci
(GCR) equations on Riemannian manifolds and the corresponding isometric
immersions of Riemannian manifolds into the Euclidean spaces. We develop a
unified intrinsic approach to establish the global weak rigidity of both the
GCR equations and isometric immersions of the Riemannian manifolds, independent
of the local coordinates, and provide further insights of the previous local
results and arguments. The critical case has also been analyzed. To achieve
this, we first reformulate the GCR equations with div-curl structure
intrinsically on Riemannian manifolds and develop a global, intrinsic version
of the div-curl lemma and other nonlinear techniques to tackle the global weak
rigidity on manifolds. In particular, a general functional-analytic compensated
compactness theorem on Banach spaces has been established, which includes the
intrinsic div-curl lemma on Riemannian manifolds as a special case. The
equivalence of global isometric immersions, the Cartan formalism, and the GCR
equations on the Riemannian manifolds with lower regularity is established. We
also prove a new weak rigidity result along the way, pertaining to the Cartan
formalism, for Riemannian manifolds with lower regularity, and extend the weak
rigidity results for Riemannian manifolds with unfixed metrics.


title:
Nuclear Physics without High-Momentum Potentials: Direct Construction of
  the Effective Interaction from Scattering Observables

abstract:
  The standard approach to nuclear physics encodes phase shift information in
an NN potential, then decodes that information in forming an effective
interaction, appropriate to a low-momentum Hilbert space. Here we show that it
is instead possible to construct the effective interaction directly from
continuum phase shifts and mixing angles, eliminating all reference to a high
momentum potential. The theory is rapidly convergent and well behaved, yielding
sub-keV accuracy.


title:
Deciding whether there are infinitely many prime graphs with forbidden
  induced subgraphs

abstract:
  A homogeneous set of a graph $G$ is a set $X$ of vertices such that $2\le
\lvert X\rvert <\lvert V(G)\rvert$ and no vertex in $V(G)-X$ has both a
neighbor and a non-neighbor in $X$. A graph is prime if it has no homogeneous
set.
  We present an algorithm to decide whether a class of graphs given by a finite
set of forbidden induced subgraphs contains infinitely many non-isomorphic
prime graphs.


title: Connectivity Oracles for Graphs Subject to Vertex Failures

abstract:
  We introduce new data structures for answering connectivity queries in graphs
subject to batched vertex failures. A deterministic structure processes a batch
of $d\leq d_{\star}$ failed vertices in $\tilde{O}(d^3)$ time and thereafter
answers connectivity queries in $O(d)$ time. It occupies space $O(d_{\star}
m\log n)$. We develop a randomized Monte Carlo version of our data structure
with update time $\tilde{O}(d^2)$, query time $O(d)$, and space $\tilde{O}(m)$
for any failure bound $d\le n$. This is the first connectivity oracle for
general graphs that can efficiently deal with an unbounded number of vertex
failures.
  We also develop a more efficient Monte Carlo edge-failure connectivity
oracle. Using space $O(n\log^2 n)$, $d$ edge failures are processed in $O(d\log
d\log\log n)$ time and thereafter, connectivity queries are answered in
$O(\log\log n)$ time, which are correct w.h.p.
  Our data structures are based on a new decomposition theorem for an
undirected graph $G=(V,E)$, which is of independent interest. It states that
for any terminal set $U\subseteq V$ we can remove a set $B$ of $|U|/(s-2)$
vertices such that the remaining graph contains a Steiner forest for $U-B$ with
maximum degree $s$.


title:
Infrared Zero of $\beta$ and Value of $\gamma_m$ for an SU(3) Gauge
  Theory at the Five-Loop Level

abstract:
  We calculate the value of the coupling at the infrared zero of the beta
function of an asymptotically free SU(3) gauge theory at the five-loop level as
a function of the number of fermions. Both a direct analysis of the beta
function and analyses of Pad\'e approximants are used for this purpose. We then
calculate the value of the five-loop anomalous dimension, $\gamma_m$, of the
fermion bilinear at this IR zero of the beta function.


title: Ultra-stable optical clock with two cold-atom ensembles

abstract:
  Atomic clocks based on optical transitions are the most stable, and therefore
precise, timekeepers available. These clocks operate by alternating intervals
of atomic interrogation with dead time required for quantum state preparation
and readout. This non-continuous interrogation of the atom system results in
the Dick effect, an aliasing of frequency noise of the laser interrogating the
atomic transition. Despite recent advances in optical clock stability achieved
by improving laser coherence, the Dick effect has continually limited optical
clock performance. Here we implement a robust solution to overcome this
limitation: a zero-dead-time optical clock based on the interleaved
interrogation of two cold-atom ensembles. This clock exhibits vanishingly small
Dick noise, thereby achieving an unprecedented fractional frequency instability
of $6 \times 10^{-17} / \sqrt{\tau}$ for an averaging time $\tau$ in seconds.
We also consider alternate dual-atom-ensemble schemes to extend laser coherence
and reduce the standard quantum limit of clock stability, achieving a
spectroscopy line quality factor $Q> 4 \times 10^{15}$.


title:
Formation and evolution of blue compact dwarfs: The origin of their
  steep rotation curves

abstract:
  The origin of the observed steep rotation curves of blue compact dwarf
galaxies (BCDs) remains largely unexplained by theoretical models of BCD
formation. We therefore investigate the rotation curves in BCDs formed from
mergers between gas-rich dwarf irregular galaxies based on the results of
numerical simulations for BCD formation. The principal results are as follows.
The dark matter of merging dwarf irregulars undergoes a central concentration
so that the central density can become up to six times higher than those of the
initial dwarf irregulars. However, the more compact dark matter halo alone can
not reproduce the gradient differences observed between dwarf irregulars and
BCDs. We provide further support that the central concentration of gas due to
rapid gas-transfer to the central regions of dwarf--dwarf mergers is
responsible for the observed difference in rotation curve gradients. The BCDs
with central gas concentration formed from merging can thus show steeply rising
rotation curves in their central regions. Such gas concentration is also
responsible for central starbursts of BCDs and the high central surface
brightness and is consistent with previous BCD studies. We discuss the
relationship between rotational velocity gradient and surface brightness, the
dependence of BCD rotation curves on star formation threshold density,
progenitor initial profile, interaction type and merger mass ratio, as well as
potential evolutionary links between dwarf irregulars, BCDs and compact dwarf
irregulars.


title: Fragmentation of protoplanetary disks around M-dwarfs

abstract:
  We investigate the conditions required for planet formation via gravitational
instability (GI) and protoplanetary disk (PPD) fragmentation around M-dwarfs.
Using a suite of 64 SPH simulations with $10^6$ particles, the parameter space
of disk mass, temperature, and radius is explored, bracketing reasonable values
based on theory and observation. Our model consists of an equilibrium, gaseous,
and locally isothermal disk orbiting a central star of mass $M_*=M_{sol}/3$.
Disks with a minimum Toomre $Q$ of $Q_{min} \lesssim 0.9$ will fragment and
form gravitationally bound clumps. Some previous literature has found $Q_{min}
< 1.3-1.5$ to be sufficient for fragmentation. Increasing disk height tends to
stabilize disks, and when incorporated into $Q$ as $Q_{eff}\propto
Q(H/R)^\alpha$ for $\alpha=0.18$ is sufficient to predict fragmentation. Some
discrepancies in the literature regarding $Q_{crit}$ may be due to different
methods of generating initial conditions (ICs). A series of 15 simulations
demonstrates that perturbing ICs slightly out of equilibrium can cause disks to
fragment for higher $Q$. Our method for generating ICs is presented in detail.
We argue that GI likely plays a role in PPDs around M-dwarfs and that disk
fragmentation at large radii is a plausible outcome for these disks.


title:
The weighted Fourier inequality, polarity, and reverse H\"older
  inequality

abstract:
  We examine the problem of the Fourier transform mapping one weighted Lebesgue
space into another, by studying necessary conditions and sufficient conditions
which expose an underlying geometry. In the necessary conditions, this geometry
is connected to an old result of Mahler concerning the the measure of a convex
set and its geometric polar being essentially reciprocal. An additional
assumption, that the weights must belong to a reverse H\"older class, is used
to formulate the sufficient condition.


title:
Deep Appearance Models: A Deep Boltzmann Machine Approach for Face
  Modeling

abstract:
  The "interpretation through synthesis" approach to analyze face images,
particularly Active Appearance Models (AAMs) method, has become one of the most
successful face modeling approaches over the last two decades. AAM models have
ability to represent face images through synthesis using a controllable
parameterized Principal Component Analysis (PCA) model. However, the accuracy
and robustness of the synthesized faces of AAM are highly depended on the
training sets and inherently on the generalizability of PCA subspaces. This
paper presents a novel Deep Appearance Models (DAMs) approach, an efficient
replacement for AAMs, to accurately capture both shape and texture of face
images under large variations. In this approach, three crucial components
represented in hierarchical layers are modeled using the Deep Boltzmann
Machines (DBM) to robustly capture the variations of facial shapes and
appearances. DAMs are therefore superior to AAMs in inferencing a
representation for new face images under various challenging conditions. The
proposed approach is evaluated in various applications to demonstrate its
robustness and capabilities, i.e. facial super-resolution reconstruction,
facial off-angle reconstruction or face frontalization, facial occlusion
removal and age estimation using challenging face databases, i.e. Labeled Face
Parts in the Wild (LFPW), Helen and FG-NET. Comparing to AAMs and other deep
learning based approaches, the proposed DAMs achieve competitive results in
those applications, thus this showed their advantages in handling occlusions,
facial representation, and reconstruction.


title:
Nonlocal minimal surfaces: interior regularity, quantitative estimates
  and boundary stickiness

abstract:
  We consider surfaces which minimize a nonlocal perimeter functional and we
discuss their interior regularity and rigidity properties, in a quantitative
and qualitative way, and their (perhaps rather surprising) boundary behavior.
We present at least a sketch of the proofs of these results, in a way that aims
to be as elementary and self contained as possible.


title:
A necessary and sufficient condition for edge universality at the
  largest singular values of covariance matrices

abstract:
  In this paper, we prove a necessary and sufficient condition for the edge
universality of sample covariance matrices with general population. We consider
sample covariance matrices of the form $\mathcal Q = TX(TX)^{*}$, where the
sample $X$ is an $M_2\times N$ random matrix with $i.i.d.$ entries with mean
zero and variance $N^{-1}$, and $T$ is an $M_1 \times M_2$ deterministic matrix
satisfying $T^* T$ is diagonal. We study the asymptotic behavior of the largest
eigenvalues of $\mathcal Q$ when $M:=\min\{M_1,M_2\}$ and $N$ tends to infinity
with $\lim_{N \to \infty} {N}/{M}=d \in (0, \infty)$. Under mild assumptions of
$T$, we prove that the Tracy-Widom law holds for the largest eigenvalue of
$\mathcal Q$ if and only if $\lim_{s \rightarrow \infty}s^4 \mathbb{P}(|
\sqrt{N} x_{ij}| \geq s)=0$. This condition was first proposed for Wigner
matrices by Lee and Yin.