title: Moments of L-functions and Liouville-Green method

abstract:
  We show that the percentage of primitive forms of level one and weight
$4k\rightarrow \infty$ for which the associated $L$-function at the central
point is no less than $(\log{k})^{-2}$ is at least 20%. The key ingredients of
our proof are the Kuznetsov convolution formula and the Liouville-Green method.


title:
Fused DNN: A deep neural network fusion approach to fast and robust
  pedestrian detection

abstract:
  We propose a deep neural network fusion architecture for fast and robust
pedestrian detection. The proposed network fusion architecture allows for
parallel processing of multiple networks for speed. A single shot deep
convolutional network is trained as a object detector to generate all possible
pedestrian candidates of different sizes and occlusions. This network outputs a
large variety of pedestrian candidates to cover the majority of ground-truth
pedestrians while also introducing a large number of false positives. Next,
multiple deep neural networks are used in parallel for further refinement of
these pedestrian candidates. We introduce a soft-rejection based network fusion
method to fuse the soft metrics from all networks together to generate the
final confidence scores. Our method performs better than existing
state-of-the-arts, especially when detecting small-size and occluded
pedestrians. Furthermore, we propose a method for integrating pixel-wise
semantic segmentation network into the network fusion architecture as a
reinforcement to the pedestrian detector. The approach outperforms
state-of-the-art methods on most protocols on Caltech Pedestrian dataset, with
significant boosts on several protocols. It is also faster than all other
methods.


title:
Deep Learning Assessment of Tumor Proliferation in Breast Cancer
  Histological Images

abstract:
  Current analysis of tumor proliferation, the most salient prognostic
biomarker for invasive breast cancer, is limited to subjective mitosis counting
by pathologists in localized regions of tissue images. This study presents the
first data-driven integrative approach to characterize the severity of tumor
growth and spread on a categorical and molecular level, utilizing multiple
biologically salient deep learning classifiers to develop a comprehensive
prognostic model. Our approach achieves pathologist-level performance on
three-class categorical tumor severity prediction. It additionally pioneers
prediction of molecular expression data from a tissue image, obtaining a
Spearman's rank correlation coefficient of 0.60 with ex vivo mean calculated
RNA expression. Furthermore, our framework is applied to identify over two
hundred unprecedented biomarkers critical to the accurate assessment of tumor
proliferation, validating our proposed integrative pipeline as the first to
holistically and objectively analyze histopathological images.


title: Algebraic proof and application of Lumley's realizability triangle

abstract:
  Lumley [Lumley J.L.: Adv. Appl. Mech. 18 (1978) 123--176] provided a
geometrical proof that any Reynolds-stress tensor $\overline{u_i'u_j'}$ (indeed
any tensor whose eigenvalues are invariably nonnegative) should remain inside
the so-called Lumley's realizability triangle. An alternative formal algebraic
proof is given that the anisotropy invariants of any positive-definite
symmetric Cartesian rank-2 tensor in the 3-D Euclidian space $\mathbb{E}^3$
define a point which lies within the realizability triangle. This general
result applies therefore not only to $\overline{u_i'u_j'}$ but also to many
other tensors that appear in the analysis and modeling of turbulent flows.
Typical examples are presented based on DNS data for plane channel flow.


title: Inclination dependence of QPO phase lags in black hole X-ray binaries

abstract:
  Quasi-periodic oscillations (QPOs) with frequencies from $\sim0.05$-$30$ Hz
are a common feature in the X-ray emission of accreting black hole binaries. As
the QPOs originate from the innermost accretion flow, they provide the
opportunity to probe the behaviour of matter in extreme gravity. In this paper,
we present a systematic analysis of the inclination dependence of phase lags
associated with both Type-B and Type-C QPOs in a sample of 15 Galactic black
hole binaries. We find that the phase lag at the Type-C QPO frequency strongly
depends on inclination, both in evolution with QPO frequency and sign. Although
we find that the Type-B QPO soft lags are associated with high inclination
sources, the source sample is too small to confirm this as a significant
inclination dependence. These results are consistent with a geometrical origin
of Type-C QPOs and a different origin for Type-B and Type-C QPOs. We discuss
the possibility that the phase lags originate from a pivoting spectral power
law during each QPO cycle, while the inclination dependence arises from
differences in dominant relativistic effects. We also search for energy
dependences in the Type-C QPO frequency. We confirm this effect in the three
known sources (GRS 1915+105, H1743-322 and XTE J1550-564) and newly detect it
in XTE J1859+226. Lastly, our results indicate that the unknown inclination
sources XTE J1859+226 and MAXI J1543-564 are most consistent with a high
inclination.


title:
MHD blood flow and heat transfer through an inclined porous stenosed
  artery with variable viscosity

abstract:
  In this article, effects of heat transfer on MHD blood flow through a
stenosed inclined porous artery with heat source have been investigated. The
viscosity of the blood is assumed to be varying radially with hematocrit
throughout the region of the artery. Governing equations have been derived by
treating blood as incompressible magnetohydrodynamic (MHD) Newtonian fluid.
Momentum and energy equations of the fluid flow are simplified under the
assumption of mild stenosis. Homotopy perturbation method (HPM) is used to
solve nonlinear differential equations for velocity and temperature profiles of
the blood flow. Variation of flow rate and shear stress for different values of
inclination angle and hematocrit parameter along the diseased part of artery
have been plotted graphically. For having the adequate insight of the flow
pattern in the diseased artery, velocity contours have been plotted for
different values of the height of the stenosis and for different inclination
angles of the artery.


title:
Automated cantilever exchange and optical alignment for High-throughput,
  parallel atomic force microscopy

abstract:
  In atomic force microscopy (AFM), the exchange and alignment of the AFM
cantilever with respect to the optical beam and position-sensitive detector
(PSD) are often performed manually. This process is tedious and time-consuming
and sometimes damages the cantilever or tip. To increase the throughput of AFM
in industrial applications, the ability to automatically exchange and align the
cantilever in a very short time with sufficient accuracy is required. In this
paper, we present the development of an automated cantilever exchange and
optical alignment instrument. We present an experimental proof of principle by
exchanging various types of AFM cantilevers in 6 seconds with an accuracy
better than 2 um. The exchange and alignment unit is miniaturized to allow for
integration in a parallel AFM. The reliability of the demonstrator has also
been evaluated. Ten thousand continuous exchange and alignment cycles were
performed without failure. The automated exchange and alignment of the AFM
cantilever overcome a large hurdle toward bringing AFM into high-volume
manufacturing and industrial applications.


title:
Computation of forward stochastic reach sets: Application to stochastic,
  dynamic obstacle avoidance

abstract:
  We propose a method to efficiently compute the forward stochastic reach (FSR)
set and its probability measure for nonlinear systems with an affine
disturbance input, that is stochastic and bounded. This method is applicable to
systems with an a priori known controller, or to uncontrolled systems, and
often arises in problems in obstacle avoidance in mobile robotics. When used as
a constraint in finite horizon controller synthesis, the FSR set, and its
probability measure facilitates probabilistic collision avoidance, in contrast
to methods which presume the obstacles act in a worst-case fashion and generate
hard constraints that cannot be violated. We tailor our approach to accommodate
rigid body constraints, and show convexity is assured so long as the rigid body
shape of each obstacle is also convex. We extend methods for multi-obstacle
avoidance through mixed integer linear programming (with linear robot and
obstacle dynamics) to accommodate chance constraints that represent the FSR set
probability measure. We demonstrate our method on a rigid-body obstacle
avoidance scenario, in which a receding horizon controller is designed to avoid
several stochastically moving obstacles while reaching the desired goal. Our
approach can provide solutions when approaches that presume a worst-case action
from the obstacle fail.


title:
Electrical spin orientation, spin-galvanic and spin-Hall effects in
  disordered two-dimensional systems

abstract:
  In disordered systems, the hopping conductivity regime is usually realized at
low temperatures where spin-related phenomena differ strongly from the case of
delocalized carriers. We develop the unified microscopic theory of current
induced spin orientation, spin-galvanic and spin-Hall effects for the
two-dimensional hopping regime. We show that the corresponding susceptibilities
are proportional to each other and determined by the interplay between the
drift and the diffusion spin currents. Estimations are made for realistic
semiconductor heterostructures using the percolation theory. We show that the
electrical spin polarization in the hopping regime increases exponentially with
increase of the concentration of localization sites and may reach a few
percents at the crossover from the hopping to the diffusion conductivity
regime.


title: The Core of the Participatory Budgeting Problem

abstract:
  In participatory budgeting, communities collectively decide on the allocation
of public tax dollars for local public projects. In this work, we consider the
question of fairly aggregating the preferences of community members to
determine an allocation of funds to projects. This problem is different from
standard fair resource allocation because of public goods: The allocated goods
benefit all users simultaneously. Fairness is crucial in participatory decision
making, since generating equitable outcomes is an important goal of these
processes. We argue that the classic game theoretic notion of core captures
fairness in the setting. To compute the core, we first develop a novel
characterization of a public goods market equilibrium called the Lindahl
equilibrium, which is always a core solution. We then provide the first (to our
knowledge) polynomial time algorithm for computing such an equilibrium for a
broad set of utility functions; our algorithm also generalizes (in a
non-trivial way) the well-known concept of proportional fairness. We use our
theoretical insights to perform experiments on real participatory budgeting
voting data. We empirically show that the core can be efficiently computed for
utility functions that naturally model our practical setting, and examine the
relation of the core with the familiar welfare objective. Finally, we address
concerns of incentives and mechanism design by developing a randomized
approximately dominant-strategy truthful mechanism building on the exponential
mechanism from differential privacy.


title: Secrecy in MIMO Networks with No Eavesdropper CSIT

abstract:
  We consider two fundamental multi-user channel models: the multiple-input
multiple-output (MIMO) wiretap channel with one helper (WTH) and the MIMO
multiple access wiretap channel (MAC-WT). In each case, the eavesdropper has
$K$ antennas while the remaining terminals have $N$ antennas each. We consider
a fast fading channel where the channel state information (CSI) of the
legitimate receiver is available at the transmitters but no channel state
information at the transmitters (CSIT) is available for the eavesdropper's
channel. We determine the optimal sum secure degrees of freedom (s.d.o.f.) for
each channel model for the regime $K\leq N$, and show that in this regime, the
MAC-WT channel reduces to the WTH in the absence of eavesdropper CSIT. For the
regime $N\leq K\leq 2N$, we obtain the optimal linear s.d.o.f., and show that
the MAC-WT channel and the WTH have the same optimal s.d.o.f. when restricted
to linear encoding strategies. In the absence of any such restrictions, we
provide an upper bound for the sum s.d.o.f. of the MAC-WT chanel in the regime
$N\leq K\leq 2N$. Our results show that unlike in the single-input
single-output (SISO) case, there is loss of s.d.o.f. for even the WTH due to
lack of eavesdropper CSIT when $K\geq N$.


title: On the number of cycles in a graph with restricted cycle lengths

abstract:
  Let $L$ be a set of positive integers. We call a (directed) graph $G$ an
$L$\emph{-cycle graph} if all cycle lengths in $G$ belong to $L$. Let $c(L,n)$
be the maximum number of cycles possible in an $n$-vertex $L$-cycle graph (we
use $\vec{c}(L,n)$ for the number of cycles in directed graphs). In the
undirected case we show that for any fixed set $L$, we have
$c(L,n)=\Theta_L(n^{\lfloor k/\ell \rfloor})$ where $k$ is the largest element
of $L$ and $2\ell$ is the smallest even element of $L$ (if $L$ contains only
odd elements, then $c(L,n)=\Theta_L(n)$ holds.) We also give a characterization
of $L$-cycle graphs when $L$ is a single element.
  In the directed case we prove that for any fixed set $L$ we have
$\vec{c}(L,n)=(1+o(1))(\frac{n-1}{k-1})^{k-1}$, where $k$ is the largest
element of $L$. We determine the exact value of $\vec{c}(\{k\},n)$ for every
$k$ and characterize all graphs attaining this maximum.


title:
Complexity and Stop Conditions for NP as General Assignment Problems,
  the Travel Salesman Problem in $\mathbb{R}^2$, Knight Tour Problem and
  Boolean Satisfiability Problem

abstract:
  This paper presents stop conditions for solving General Assignment Problems
(GAP), in particular for Travel Salesman Problem in an Euclidian 2D space the
well known condition Jordan's simple curve and opposite condition for the
Knight Tour Problem. The Jordan's simple curve condition means that a optimal
trajectory must be simple curve, i.e., without crossing but for Knight Tour
Problem we use the contrary, the feasible trajectory must have crossing in all
cities of the tour. The paper presents the algorithms, examples and some
results come from Concorde's Home page. Several problem are studied to depict
their properties. A classical decision problem SAT is studied in detail.


title: Whitham modulation theory for the Kadomtsev-Petviashvili equation

abstract:
  The genus-1 KP-Whitham system is derived for both variants of the
Kadomtsev-Petviashvili (KP) equation (namely, the KPI and KPII equations). The
basic properties of the KP-Whitham system, including symmetries, exact
reductions, and its possible complete integrability, together with the
appropriate generalization of the one-dimensional Riemann problem for the
Korteweg-deVries equation are discussed. Finally, the KP-Whitham system is used
to study the linear stability properties of the genus-1 solutions of the KPI
and KPII equations; it is shown that all genus-1 solutions of KPI are linearly
unstable while all genus-1 solutions of KPII {are linearly stable within the
context of Whitham theory.


title: On the Global Stability of a Beta-Plane Equation

abstract:
  We study the motion of an incompressible, inviscid two-dimensional fluid in a
rotating frame of reference. There the fluid experiences a Coriolis force,
which we assume to be linearly dependent on one of the coordinates. This is a
common approximation in geophysical fluid dynamics and is referred to as
beta-plane. In vorticity formulation the model we consider is then given by the
Euler equation with the addition of a linear anisotropic, non-degenerate,
dispersive term. This allows us to treat the problem as a quasilinear
dispersive equation whose linear solutions exhibit decay in time at a critical
rate.
  Our main result is the global stability and decay to equilibrium of
sufficiently small and localized solutions. Key aspects of the proof are the
exploitation of a "double null form" that annihilates interactions between
spatially coherent waves and a lemma for Fourier integral operators which
allows us to control a strong weighted norm.


title:
Attribution of Responsibility and Blame Regarding a Man-made Disaster:
  #FlintWaterCrisis

abstract:
  Attribution of responsibility and blame are important topics in political
science especially as individuals tend to think of political issues in terms of
questions of responsibility, and as blame carries far more weight in voting
behavior than that of credit. However, surprisingly, there is a paucity of
studies on the attribution of responsibility and blame in the field of disaster
research.
  The Flint water crisis is a story of government failure at all levels. By
studying microblog posts about it, we understand how citizens assign
responsibility and blame regarding such a man-made disaster online. We form
hypotheses based on social scientific theories in disaster research and then
operationalize them on unobtrusive, observational social media data. In
particular, we investigate the following phenomena: the source for blame; the
partisan predisposition; the concerned geographies; and the contagion of
complaining.
  This paper adds to the sociology of disasters research by exploiting a new,
rarely used data source (the social web), and by employing new computational
methods (such as sentiment analysis and retrospective cohort study design) on
this new form of data. In this regard, this work should be seen as the first
step toward drawing more challenging inferences on the sociology of disasters
from "big social data".


title:
Soft behavior of a closed massless state in superstring and universality
  in the soft behavior of the dilaton

abstract:
  We consider the tree-level scattering amplitudes in the NS-NS (Neveu-Schwarz)
massless sector of closed superstrings in the case where one external state
becomes soft. We compute the amplitudes generically for any number of
dimensions and any number and kind of the massless closed states through the
subsubleading order in the soft expansion. We show that, when the soft state is
a graviton or a dilaton, the full result can be expressed as a soft theorem
factorizing the amplitude in a soft and a hard part. This behavior is similar
to what has previously been observed in field theory and in the bosonic string.
Differently from the bosonic string, the supersymmetric soft theorem for the
graviton has no string corrections at subsubleading order. The dilaton soft
theorem, on the other hand, is found to be universally free of string
corrections in any string theory.


title: Rapid Black Hole Growth under Anisotropic Radiation Feedback

abstract:
  Discovery of high-redshift (z > 6) supermassive black holes (BHs) may
indicate that the rapid (or super-Eddington) gas accretion has aided their
quick growth. Here, we study such rapid accretion of the primordial gas on to
intermediate-mass (10^2 - 10^5 M_sun) BHs under anisotropic radiation feedback.
We perform two-dimensional radiation hydrodynamics simulations that solve the
flow structure across the Bondi radius, from far outside of the Bondi radius
down to a central part which is larger than a circum-BH accretion disc. The
radiation from the unresolved circum-BH disc is analytically modeled
considering self-shadowing effect. We show that the flow settles into a steady
state, where the flow structure consists of two distinct parts: (1) bipolar
ionized outflowing regions, where the gas is pushed outward by thermal gas
pressure and super-Eddington radiation pressure, and (2) an equatorial neutral
inflowing region, where the gas falls toward the central BH without affected by
radiation feedback. The resulting accretion rate is much higher than that in
the case of isotropic radiation, far exceeding the Eddington-limited rate to
reach a value slightly lower than the Bondi one. The opening angle of the
equatorial inflowing region is determined by the luminosity and directional
dependence of the central radiation. We find that photoevaporation from its
surfaces set the critical opening angle of about ten degrees below which the
accretion to the BH is quenched. We suggest that the shadowing effect allows
even stellar-remnant BHs to grow rapidly enough to become high-redshift
supermassive BHs.


title: Learning in Implicit Generative Models

abstract:
  Generative adversarial networks (GANs) provide an algorithmic framework for
constructing generative models with several appealing properties: they do not
require a likelihood function to be specified, only a generating procedure;
they provide samples that are sharp and compelling; and they allow us to
harness our knowledge of building highly accurate neural network classifiers.
Here, we develop our understanding of GANs with the aim of forming a rich view
of this growing area of machine learning---to build connections to the diverse
set of statistical thinking on this topic, of which much can be gained by a
mutual exchange of ideas. We frame GANs within the wider landscape of
algorithms for learning in implicit generative models--models that only specify
a stochastic procedure with which to generate data--and relate these ideas to
modelling problems in related fields, such as econometrics and approximate
Bayesian computation. We develop likelihood-free inference methods and
highlight hypothesis testing as a principle for learning in implicit generative
models, using which we are able to derive the objective function used by GANs,
and many other related objectives. The testing viewpoint directs our focus to
the general problem of density ratio estimation. There are four approaches for
density ratio estimation, one of which is a solution using classifiers to
distinguish real from generated data. Other approaches such as divergence
minimisation and moment matching have also been explored in the GAN literature,
and we synthesise these views to form an understanding in terms of the
relationships between them and the wider literature, highlighting avenues for
future exploration and cross-pollination.


title:
Multi-scale computational homogenisation to predict the long-term
  durability of composite structures

abstract:
  A coupled hygro-thermo-mechanical computational model is proposed for fibre
reinforced polymers, formulated within the framework of Computational
Homogenisation (CH). At each macrostructure Gauss point, constitutive matrices
for thermal, moisture transport and mechanical responses are calculated from CH
of the underlying representative volume element (RVE). A degradation model,
developed from experimental data relating evolution of mechanical properties
over time for a given exposure temperature and moisture concentration is also
developed and incorporated in the proposed computational model. A unified
approach is used to impose the RVE boundary conditions, which allows convenient
switching between linear Dirichlet, uniform Neumann and periodic boundary
conditions. A plain weave textile composite RVE consisting of yarns embedded in
a matrix is considered in this case. Matrix and yarns are considered as
isotropic and transversely isotropic materials respectively. Furthermore, the
computational framework utilises hierarchic basis functions and designed to
take advantage of distributed memory high-performance computing.


title:
Dynamically enriched topological orders in driven two-dimensional
  systems

abstract:
  Time-periodic driving of a quantum system can enable new dynamical
topological phases of matter that could not exist in thermal equilibrium. We
investigate two related classes of dynamical topological phenomena in 2D
systems: Floquet symmetry protected topological phases (FSPTs), and Floquet
enriched topological orders (FETs). By constructing solvable lattice models for
a complete set of 2D bosonic FSPT phases, we show that bosonic FSPTs can be
understood as topological pumps which deposit loops of 1D SPT chains onto the
boundary during each driving cycle, which protects a non-trivial edge state by
dynamically tuning the edge to a self-dual point poised between the 1D SPT and
trivial phases of the edge. By coupling these FSPT models to dynamical gauge
fields, we construct solvable models of FET orders in which anyon excitations
are dynamically transmuted into topologically distinct anyon types during each
driving period. These bosonic FSPT and gauged FSPT models are classified by
group cohomology methods. In addition, we also construct examples of "beyond
cohomology" FET orders, which can be viewed as topological pumps of 1D
topological chains formed of emergent anyonic quasi-particles.


title: Boosted Dark Matter at Neutrino Experiments

abstract:
  Current and future neutrino experiments can be used to discover dark matter,
not only in searches for dark matter annihilating to neutrinos, but also in
scenarios where dark matter itself scatters off Standard Model particles in the
detector. In this work, we study the sensitivity of different neutrino
detectors to a class of models called boosted dark matter, in which a
subdominant component of a dark sector acquires a large Lorentz boost today
through annihilation of a dominant component in a dark matter-dense region,
such as the galactic center or dwarf spheroidal galaxies. This analysis focuses
on the sensitivity of different neutrino detectors, specifically the
Cherenkov-based Super-K and the future argon-based DUNE to boosted dark matter
that scatters off electrons. We study the dependence of the expected limits on
the experimental features, such as energy threshold, volume and exposure in the
limit of constant scattering amplitude. We highlight experiment-specific
features that enable current and future neutrino experiments to be a powerful
tool in finding signatures of boosted dark matter.


title:
A systematic search for X-ray cavities in galaxy clusters, groups, and
  elliptical galaxies

abstract:
  We perform a comprehensive study of X-ray cavities using a large sample of
X-ray targets selected from the Chandra archive. The sample is selected to
cover a large dynamic range including galaxy clusters, groups, and individual
galaxies. Using $\beta$-modeling and unsharp masking techniques, we investigate
the presence of X-ray cavities for 133 targets that have sufficient X-ray
photons for analysis. We detect 148 X-ray cavities from 69 targets and measure
their properties, including cavity size, angle, and distance from the center of
the diffuse X-ray gas. We confirm the strong correlation between cavity size
and distance from the X-ray center similar to previous studies (i.e., Birzan et
al. 2004; Diehl et al. 2008; Dong et al. 2010). We find that the detection
rates of X-ray cavities are similar among galaxy clusters, groups and
individual galaxies, suggesting that the formation mechanism of X-ray cavities
is independent of environment.


title:
Information Content of the Angular Multipoles of Redshift-Space Galaxy
  Bispectrum

abstract:
  The redshift-space bispectrum (three point statistics) of galaxies depends on
the expansion rate, the growth rate, and geometry of the Universe, and hence
can be used to measure key cosmological parameters. In a homogeneous Universe
the bispectrum is a function of five variables and unlike its two point
statistics counterpart -- the power spectrum, which is a function of only two
variables -- is difficult to analyse unless the information is somehow reduced.
The most commonly considered reduction schemes rely on computing angular
integrals over possible orientations of the bispectrum triangle, thus reducing
it to sets of function of only three variables describing the triangle shape.
We use Fisher information formalism to study the information loss associated
with this angular integration. Without any reduction, the bispectrum alone can
deliver constraints on the growth rate parameter $f$ that are better by a
factor of $2.5$ compared to the power spectrum, for a sample of luminous red
galaxies expected from near future galaxy surveys at a redshift of $z\sim0.65$.
At lower redshifts the improvement could be up to a factor of $3$. We find that
most of the information is in the azimuthal averages of the first three even
multipoles. This suggests that the bispectrum of every configuration can be
reduced to just three numbers (instead of a 2D function) without significant
loss of cosmologically relevant information.


title:
GeMS/GSAOI photometric and astrometric performance in dense stellar
  fields

abstract:
  Ground-based imagers at 8m class telescopes assisted by Multi conjugate
Adaptive Optics are primary facilities to obtain accurate photometry and proper
motions in dense stellar fields. We observed the central region of the globular
clusters Liller 1 and NGC 6624 with the Gemini Multi-conjugate adaptive optics
System (GeMS) feeding the Gemini South Adaptive Optics Imager (GSAOI) currently
available at the Gemini South telescope, under different observing conditions.
We characterized the stellar Point Spread Function (PSF) in terms of Full Width
at Half Maximum (FWHM), Strehl Ratio (SR) and Encircled Energy (EE), over the
field of view. We found that, for sub-arcsec seeing at the observed airmass,
diffraction limit PSF FWHM ($\approx$ 80 mas), SR $\sim40\%$ and EE $\ge50\%$
with a dispersion around $10\%$ over the 85" x 85" field of view, can be
obtained in the $K_s$ band. In the $J$ band the best images provide FWHMs
between 60 and 80 mas, SR $>10\%$ and EE $>40\%$. For seeing at the observed
airmass exceeding 1", the performance worsen but it is still possible to
perform PSF fitting photometry with $25\%$ EE in $J$ and $40\%$ in $K_s$. We
also computed the geometric distortions of GeMS/GSAOI and we obtained corrected
images with an astrometric accuracy of $\sim$1 mas in a stellar field with high
crowding.


title:
Novel calibrations of virial black hole mass estimators in active
  galaxies based on X-ray luminosity and optical/NIR emission lines

abstract:
  Accurately weigh the masses of SMBH in AGN is currently possible for only a
small group of local and bright broad-line AGN through reverberation mapping
(RM). Statistical demographic studies can be carried out considering the
empirical scaling relation between the size of the BLR and the AGN optical
continuum luminosity. However, there are still biases against low-luminosity or
reddened AGN, in which the rest-frame optical radiation can be severely
absorbed/diluted by the host and the BLR emission lines could be hard to
detect. Our purpose is to widen the applicability of virial-based SE relations
to reliably measure the BH masses also for low-luminosity or intermediate/type
2 AGN that are missed by current methodology. We achieve this goal by
calibrating virial relations based on unbiased quantities: the hard X-ray
luminosities, in the 2-10 keV and 14-195 keV bands, that are less sensitive to
galaxy contamination, and the FWHM of the most important rest-frame NIR and
optical BLR emission lines. We built a sample of RM AGN having both X-ray
luminosity and broad optical/NIR FWHM measurements available in order to
calibrate new virial BH mass estimators. We found that the FWHM of the
H$\alpha$, H$\beta$ and NIR lines (i.e. Pa$\alpha$, Pa$\beta$ and
HeI$\lambda$10830) all correlate each other having negligible or small offsets.
This result allowed us to derive virial BH mass estimators based on either the
2-10 keV or 14-195 keV luminosity. We took also into account the recent
determination of the different virial coefficients $f$ for pseudo and classical
bulges. By splitting the sample according to the bulge type and adopting
separate $f$ factors we found that our virial relations predict BH masses of
AGN hosted in pseudobulges $\sim$0.5 dex smaller than in classical bulges.
Assuming the same average $f$ factor for both populations, a difference of
$\sim$0.2 dex is still found.


title:
Damping of hard excitations in strongly coupled $\mathcal N\,{=}\,4$
  plasma

abstract:
  The damping of high momentum excitations in strongly coupled maximally
supersymmetric Yang-Mills plasma is studied. Previous calculations of the
asymptotic behavior of the quasinormal mode spectrum are extended and
clarified. We confirm that subleading corrections to the lightlike dispersion
relation $\omega({\bf q}) = |{\bf q}|$ have a universal $|{\bf q}|^{-1/3}$
form. Sufficiently narrow, weak planar shocks may be viewed as coherent
superpositions of short wavelength quasinormal modes. The attenuation and
evolution in profile of narrow planar shocks are examined as an application of
our results.


title: Galaxy-galaxy and galaxy-cluster lensing with the SDSS and FIRST surveys

abstract:
  We perform a galaxy-galaxy lensing study by correlating the shapes of
$\sim$2.7 $\times$ 10$^5$ galaxies selected from the VLA FIRST radio survey
with the positions of $\sim$38.5 million SDSS galaxies, $\sim$132000 BCGs and
$\sim$78000 SDSS galaxies that are also detected in the VLA FIRST survey. The
measurements are conducted on angular scales ${\theta}$ $\lesssim$ 1200 arcsec.
On scales ${\theta}$ $\lesssim$ 200 arcsec we find that the measurements are
corrupted by residual systematic effects associated with the instrumental beam
of the VLA data. Using simulations we show that we can successfully apply a
correction for these effects. Using the three lens samples (the SDSS DR10
sample, the BCG sample and the SDSS-FIRST matched object sample) we measure a
tangential shear signal that is inconsistent with zero at the 10${\sigma}$,
3.8${\sigma}$ and 9${\sigma}$ level respectively. Fitting an NFW model to the
detected signals we find that the ensemble mass profile of the BCG sample
agrees with the values in the literature. However, the mass profiles of the
SDSS DR10 and the SDSS-FIRST matched object samples are found to be shallower
and steeper than results in the literature respectively. The best-fitting
Virial masses for the SDSS DR10, BCG and SDSS-FIRST matched samples, derived
using an NFW model and allowing for a varying concentration factor, are
M$^{SDSS-DR10}_{200}$ = (1.2 $\pm$ 0.4) $\times$ 10$^{12}$M$_{\odot}$,
M$^{BCG}_{200}$ = (1.4 $\pm$ 1.3) $\times$ 10$^{13}$M$_{\odot}$ and
M$^{SDSS-FIRST}_{200}$ = 8.0 $\pm$ 4.2 $\times$ 10$^{13}$M$_{\odot}$
respectively. These results are in good agreement (within $\sim$2${\sigma}$)
with values in the literature. Our findings suggest that for galaxies to be
both bright in the radio and in the optical they must be embedded in very dense
environment on scales R $\lesssim$ 1Mpc.


title:
A unifying evolutionary framework for infrared-selected obscured and
  unobscured quasar host haloes

abstract:
  Recent measurements of the dark matter halo masses of infrared-selected
obscured quasars are in tension --- some indicate that obscured quasars have
higher halo mass compared to their unobscured counterparts, while others find
no difference. The former result is inconsistent with the simplest models of
quasar unification that rely solely on viewing angle, while the latter may
support such models. Here, using empirical relationships between dark matter
halo and supermassive black hole masses, we provide a simple evolutionary
picture that naturally explains these findings and is motivated by more
sophisticated merger-driven quasar fueling models. The model tracks the growth
rate of haloes, with the black hole growing in spurts of quasar activity in
order to "catch-up" with the $M_{\textrm{BH}}$ - $M_{\textrm{star}}$ -
$M_{\textrm{halo}}$ relationship. The first part of the quasar phase is
obscured and is followed by an unobscured phase. Depending on the luminosity
limit of the sample, driven by observational selection effects, a difference in
halo masses may or may not be significant. For high luminosity samples, the
difference can be large (a few to 10 times higher masses in obscured quasars),
while for lower luminosity samples the halo mass difference is very small, much
smaller than current observational constraints. Such a simple model provides a
qualitative explanation for the higher mass haloes of obscured quasars, as well
as rough quantitative agreement with seemingly disparate results.


title:
The decay $\eta \to 3 \pi$: study of the Dalitz plot and extraction of
  the quark mass ratio $Q$

abstract:
  The $\eta \to 3 \pi$ amplitude is sensitive to the quark mass difference
$m_u-m_d$ and offers a unique way to determine the quark mass ratio $Q^2 \equiv
(m_s^2-m_{ud}^2)/(m_d^2-m_u^2)$ from experiment. We calculate the amplitude
dispersively and fit the KLOE data on the charged mode, varying the subtraction
constants in the range allowed by chiral perturbation theory. The
parameter-free predictions obtained for the neutral Dalitz plot and the
neutral-to-charged branching ratio are in excellent agreement with experiment.
Our representation of the transition amplitude implies $Q = 22.0 \pm 0.7$.


title:
A New Diagnostic Diagram of Ionization Source for High Redshift Emission
  Line Galaxies

abstract:
  We propose a new diagram, the Kinematic-Excitation diagram (KEx diagram),
which uses the [OIII]/H\beta\ line ratio and the [OIII]5007 emission line width
(\sigma_{[OIII]}) to diagnose the ionization source and physical properties of
the Active Galactic Nuclei (AGNs) and the star-forming galaxies (SFGs). The KEx
diagram is a suitable tool to classify emission-line galaxies (ELGs) at
intermediate redshift because it uses only the [OIII]5007 and H\beta\ emission
lines. We use the SDSS DR7 main galaxy sample and the
Baldwin-Phillips-Terlevich (BPT) diagnostic to calibrate the diagram at low
redshift. We find that the diagram can be divided into 3 regions: one occupied
mainly by the pure AGNs (KEx-AGN region), one dominated by composite galaxies
(KEx-composite region), and one contains mostly SFGs (KEx-SFG region). AGNs are
separated from SFGs in this diagram mainly because they preferentially reside
in luminous and massive galaxies and have high [OIII]/H\beta. The separation of
AGN from star-forming galaxies is even cleaner thanks to the additional
0.15/0.12 dex offset in [OIII] line width at fixed luminosity/stellar mass. We
apply the KEx diagram to 7,866 galaxies at 0.3 < z < 1 in the DEEP2 Galaxy
Redshift Survey, and compare it to an independent X-ray classification scheme
using Chandra observation. X-ray AGNs are mostly located in the KEx-AGN region
while X-ray SFGs are mostly located in the KEx-SFG region. Almost all of Type1
AGNs lie in the KEx-AGN region. These confirm the reliability of this
classification diagram for emission line galaxies at intermediate redshift. At
z~2, the demarcation line between star-forming galaxies and AGNs should shift
0.3 dex higher in \sigma_{[OIII]} to account for evolution.


title: Hairy black holes and the endpoint of AdS$_4$ charged superradiance

abstract:
  We construct hairy black hole solutions that merge with the anti-de Sitter
(AdS$_4$) Reissner-Nordstr\"om black hole at the onset of superradiance. These
hairy black holes have, for a given mass and charge, higher entropy than the
corresponding AdS$_4$-Reissner-Nordstr\"om black hole. Therefore, they are
natural candidates for the endpoint of the charged superradiant instability. On
the other hand, hairy black holes never dominate the canonical and
grand-canonical ensembles. The zero-horizon radius of the hairy black holes is
a soliton (i.e. a boson star under a gauge transformation). We construct our
solutions perturbatively, for small mass and charge, so that the properties of
hairy black holes can be used to testify and compare with the endpoint of
initial value simulations. We further discuss the near-horizon scalar
condensation instability which is also present in global
AdS$_4$-Reissner-Nordstr\"om black holes. We highlight the different nature of
the near-horizon and superradiant instabilities and that hairy black holes
ultimately exist because of the non-linear instability of AdS.


title:
Self-force corrections to the periapsis advance around a spinning black
  hole

abstract:
  The linear in mass ratio correction to the periapsis advance of equatorial
orbits around a spinning black hole is calculated for the first time and to
very high precision, providing a key benchmark for different approaches
modelling spinning binaries. The high precision of the calculation is leveraged
to discriminate between two recent incompatible derivations of the 4PN
equations of motion. Finally, the limit of the periapsis advance near the
innermost stable orbit (ISCO) allows determination of the ISCO shift,
validating previous calculations using the first law of binary mechanics.
Calculation of the ISCO shift is further extended into the near extremal regime
(with spins up to $1-a=10^{-20}$), revealing new unexpected phenomenology. In
particular, we find that the shift of the ISCO does not have a well defined
extremal limit, but instead continues to oscillate.


title:
Why do high-redshift galaxies show diverse gas-phase metallicity
  gradients?

abstract:
  Recent spatially resolved observations of galaxies at z=0.6-3 reveal that
high-redshift galaxies show complex kinematics and a broad distribution of
gas-phase metallicity gradients. To understand these results, we use a suite of
high-resolution cosmological zoom-in simulations from the Feedback in Realistic
Environments (FIRE) project, which include physically motivated models of the
multi-phase ISM, star formation, and stellar feedback. Our simulations
reproduce the observed diversity of kinematic properties and metallicity
gradients, broadly consistent with observations at z=0-3. Strong negative
metallicity gradients only appear in galaxies with a rotating disk, but not all
rotationally supported galaxies have significant gradients. Strongly perturbed
galaxies with little rotation always have flat gradients. The kinematic
properties and metallicity gradient of a high-redshift galaxy can vary
significantly on short time-scales, associated with starburst episodes.
Feedback from a starburst can destroy the gas disk, drive strong outflows, and
flatten a pre-existing negative metallicity gradient. The time variability of a
single galaxy is statistically similar to the entire simulated sample,
indicating that the observed metallicity gradients in high-redshift galaxies
reflect the instantaneous state of the galaxy rather than the accretion and
growth history on cosmological time-scales. We find weak dependence of
metallicity gradient on stellar mass and specific star formation rate (sSFR).
Low-mass galaxies and galaxies with high sSFR tend to have flat gradients,
likely due to the fact that feedback is more efficient in these galaxies. We
argue that it is important to resolve feedback on small scales in order to
produce the diverse metallicity gradients observed.


title:
The Galactic Center Molecular Cloud Survey. I. A Steep Linewidth-Size
  Relation & Suppression of Star Formation

abstract:
  The Central Molecular Zone (CMZ; inner $\sim{}200~\rm{}pc$) of the Milky Way
is a star formation (SF) environment with very extreme physical properties.
Exploration of SF in this region is important because (i) this region allows us
to test models of star formation under exceptional conditions, and (ii) the CMZ
clouds might be suitable to serve as templates to understand the physics of
starburst galaxies in the nearby and the distant universe. For this reason we
launched the Galactic Center Molecular Cloud Survey (GCMS), the first
systematic study that resolves all major CMZ clouds at interferometer angular
resolution (i.e., a few arc seconds). Here we present initial results based on
observations with the Submillimeter Array (SMA) and the Atacama Pathfinder
Experiment (APEX). Our study is complemented by dust emission data from the
Herschel Space Telescope and a comprehensive literature survey of CMZ star
formation activity. Our research reveals (i) an unusually steep linewidth-size
relation, $\sigma(v)\propto{}r_{\rm{}eff}^{0.66\pm{}0.18}$, down to velocity
dispersions $\sim{}0.6~\rm{}km\,s^{-1}$ at 0.1 pc scale. This scaling law
potentially results from the decay of gas motions to transonic velocities in
strong shocks. The data also show that, relative to dense gas in the solar
neighborhood, (ii) star formation is suppressed by factors $\gtrsim{}10$ in
individual CMZ clouds. This observation encourages exploration of processes
that can suppress SF inside dense clouds for a significant period of time.


title:
The Tarantula Massive Binary Monitoring: I. Observational campaign and
  OB-type spectroscopic binaries

abstract:
  Massive binaries (MBs) play a crucial role in the Universe. Knowing the
distributions of their orbital parameters (OPs) is important for a wide range
of topics, from stellar feedback to binary evolution channels, from the
distribution of supernova types to gravitational wave progenitors, yet, no
direct measurements exist outside the Milky Way. The Tarantula Massive Binary
Monitoring was designed to help fill this gap by obtaining multi-epoch radial
velocity monitoring of 102 MBs in the 30 Dor. In this paper, we analyse 32
VLT/FLAMES observations of 93 O- and 7 B-type binaries. We performed a Fourier
analysis and obtained orbital solutions for 82 systems: 51 single- and 31
double-lined spectroscopic binaries. Overall, the OPs and binary fraction are
remarkably similar across the 30 Dor region and compared to existing Galactic
samples (GSs). This indicates that within these domains environmental effects
are of second order in shaping the properties of MBs. A small difference is
found in the distribution of orbital periods (OrbPs), which is slightly flatter
(in log space) in 30 Dor than in the Galaxy, although this may be compatible
within error estimates and differences in the fitting methodology. Also, OrbPs
in 30 Dor can be as short as 1.1 d; somewhat shorter than seen in GSs. Equal
mass binaries q>0.95 in 30 Dor are all found outside NGC 2070 the very young
and massive cluster at 30 Dor's core. One outstanding exception however is the
fact that earliest spectral types (O2-O7) tend to have shorter OrbPs than
latter (O9.2-O9.7). Our results point to a relative universality of the
incidence rate of MBs and their OPs in the metallicity range from solar
($Z_{\odot}$) to about $0.5Z_{\odot}$. This provides the first direct
constraints on MB properties in massive star-forming galaxies at the Universes
peak of star formation at redshifts z~1 to 2, which are estimated to have
$Z~0.5Z_{\odot}$.


title: Intersecting Surface Defects and Two-Dimensional CFT

abstract:
  We initiate the study of intersecting surface operators/defects in
four-dimensional quantum field theories (QFTs). We characterize these defects
by coupled 4d/2d/0d theories constructed by coupling the degrees of freedom
localized at a point and on intersecting surfaces in spacetime to each other
and to the four-dimensional QFT. We construct supersymmetric intersecting
surface defects preserving just two supercharges in N = 2 gauge theories. These
defects are amenable to exact analysis by localization of the partition
function of the underlying 4d/2d/0d QFT. We identify the 4d/2d/0d QFTs that
describe intersecting surface operators in N = 2 gauge theories realized by
intersecting M2-branes ending on N M5-branes wrapping a Riemann surface. We
conjecture and provide evidence for an explicit equivalence between the
squashed four-sphere partition function of these intersecting defects and
correlation functions in Liouville/Toda CFT with the insertion of arbitrary
degenerate vertex operators, which are labeled by representations of SU(N).


title:
The Galactic Center Molecular Cloud Survey. II. A Lack of Dense Gas &
  Cloud Evolution along Galactic Center Orbits

abstract:
  We present the first systematic study of the density structure of clouds
found in a complete sample covering all major molecular clouds in the Central
Molecular Zone (CMZ; inner $\sim{}200~\rm{}pc$) of the Milky Way. This is made
possible by using data from the Galactic Center Molecular Cloud Survey (GCMS),
the first study resolving all major molecular clouds in the CMZ at
interferometer angular resolution. We find that many CMZ molecular clouds have
unusually shallow density gradients compared to regions elsewhere in the Milky
Way. This is possibly a consequence of weak gravitational binding of the
clouds. The resulting relative absence of dense gas on spatial scales
$\sim{}0.1~\rm{}pc$ is probably one of the reasons why star formation (SF) in
dense gas of the CMZ is suppressed by a factor $\sim{}10$, compared to solar
neighborhood clouds. Another factor suppressing star formation are the high SF
density thresholds that likely result from the observed gas kinematics.
Further, it is possible but not certain that the star formation activity and
the cloud density structure evolve systematically as clouds orbit the CMZ.


title: Interacting Brownian Motion with Resetting

abstract:
  We study two Brownian particles in dimension $d=1$, diffusing under an
interacting resetting mechanism to a fixed position. The particles are subject
to a constant drift, which biases the Brownian particles toward each other. We
derive the steady-state distributions and study the late time relaxation
behavior to the stationary state.


title:
The Broadband and Spectrally-Resolved H-band Eclipse of KELT-1b and the
  Role of Surface Gravity in Stratospheric Inversions in Hot Jupiters

abstract:
  We present a high precision H-band emission spectrum of the transiting brown
dwarf KELT-1b, which we spectrophotometrically observed during a single
secondary eclipse using the LUCI1 multi-object spectrograph on the Large
Binocular Telescope. Using a Gaussian-process regression model, we are able to
clearly measure the broadband eclipse depth as Delta-H=1418+/-94ppm. We are
also able to spectrally-resolve the H-band into five separate wavechannels and
measure the eclipse spectrum of KELT-1b at R~50 with an average precision of
+/-135ppm. We find that the day side has an average brightness temperature of
3250+/-50K, with significant variation as a function of wavelength. Based on
our observations, and previous measurements of KELT-1b's eclipse at other
wavelengths, we find that KELT-1b's day side appears identical to an isolated
3200K brown dwarf, and our modeling of the atmospheric emission shows a
monotonically decreasing temperature-pressure profile. This is in contrast to
hot Jupiters with similar day side brightness temperatures near 3000K, all of
which appear to be either isothermal or posses a stratospheric temperature
inversion. We hypothesize that the lack of an inversion in KELT-1b is due to
its high surface gravity, which we argue could be caused by the increased
efficiency of cold-trap processes within its atmosphere.


title:
Variability in GRMHD simulations of Sgr A$^*$: Implications for EHT
  closure phase observations

abstract:
  The observable quantities that carry the most information regarding the
structures of the images of black holes in the interferometric observations
with the Event Horizon Telescope are the closure phases along different
baseline triangles. We use long time span, high cadence, GRMHD+radiative
transfer models of Sgr A$^*$ to investigate the expected variability of closure
phases in such observations. We find that, in general, closure phases along
small baseline triangles show little variability, except in the cases when one
of the triangle vertices crosses one of a small regions of low visibility
amplitude. The closure phase variability increases with the size of the
baseline triangle, as larger baselines probe the small-scale structures of the
images, which are highly variable. On average, the jet-dominated MAD models
show less closure phase variability than the disk-dominated SANE models, even
in the large baseline triangles, because the images from the latter are more
sensitive to the turbulence in the accretion flow. Our results suggest that
image reconstruction techniques need to explicitly take into account the
closure phase variability, especially if the quality and quantity of data allow
for a detailed characterization of the nature of variability. This also implies
that, if image reconstruction techniques that rely on the assumption of a
static image are utilized, regions of the $u-v$ space that show a high level of
variability will need to be identified and excised.


title:
The clustering of galaxies in the completed SDSS-III Baryon Oscillation
  Spectroscopic Survey: theoretical systematics and Baryon Acoustic
  Oscillations in the galaxy correlation function

abstract:
  We investigate the potential sources of theoretical systematics in the
anisotropic Baryon Acoustic Oscillation (BAO) distance scale measurements from
the clustering of galaxies in configuration space using the final Data Release
(DR12) of the Baryon Oscillation Spectroscopic Survey (BOSS). We perform a
detailed study of the impact on BAO measurements from choices in the
methodology such as fiducial cosmology, clustering estimators, random
catalogues, fitting templates, and covariance matrices.
  The theoretical systematic uncertainties in BAO parameters are found to be
0.002 in the isotropic dilation $\alpha$ and 0.003 in the quadrupolar dilation
$\epsilon$. The leading source of systematic uncertainty is related to the
reconstruction techniques. Theoretical uncertainties are sub-dominant compared
with the statistical uncertainties for BOSS survey, accounting
$0.2\sigma_{stat}$ for $\alpha$ and $0.25\sigma_{stat}$ for $\epsilon$
  ($\sigma_{\alpha,stat} \sim$0.010 and $\sigma_{\epsilon,stat}\sim$ 0.012
respectively). We also present BAO-only distance scale constraints from the
anisotropic analysis of the correlation function. Our constraints on the
angular diameter distance $D_A(z)$ and the Hubble parameter $H(z)$, including
both statistical and theoretical systematic uncertainties, are 1.5\% and 2.8\%
at $z_{\rm eff}=0.38$, 1.4\% and 2.4\% at $z_{\rm eff}=0.51$, and 1.7\% and
2.6\% at $z_{\rm eff}=0.61$. This paper is part of a set that analyzes the
final galaxy clustering dataset from BOSS. The measurements and likelihoods
presented here are cross-checked with other BAO analysis in \citet{Acacia16}.
The systematic error budget concerning the methodology on post-reconstruction
BAO analysis presented here is used in \citet{Acacia16} to produce the final
cosmological constraints from BOSS.


title: Quantum fault tolerance in small experiments

abstract:
  I discuss a variety of issues relating to near-future experiments
demonstrating fault-tolerant quantum computation. I describe a family of
fault-tolerant quantum circuits that can be performed with 5 qubits arranged on
a ring with nearest-neighbor interactions. I also present a criterion whereby
we can say that an experiment has succeeded in demonstrating fault tolerance.
Finally, I discuss the possibility of using future fault-tolerant experiments
to answer important questions about the interaction of fault-tolerant protocols
with real experimental errors.


title:
On the free-precession candidate PSR B1828-11: Evidence for increasing
  deformation

abstract:
  We observe that the periodic variations in spin-down rate and beam-width of
the radio pulsar PSR B1828-11 are getting faster. In the context of a free
precession model, this corresponds to a decrease in the precession period
$P_{\mathrm{fp}}$. We investigate how a precession model can account for such a
decrease in $P_{\mathrm{fp}}$, in terms of an increase over time in the
absolute biaxial deformation ($|\epsilon_{\mathrm{p}}|{\sim}10^{-8}$) of this
pulsar. We perform a Bayesian model comparison against the 'base' precession
model (with constant $\epsilon_{\mathrm{p}}$) developed in Ashton et al (2016),
and we obtain decisive odds in favour of a time-varying deformation. We study
two types of time-variation: (i) a linear drift with a posterior estimate of
$\dot{\epsilon}_{\mathrm{p}}{\sim}10^{-18}\,\mathrm{s}^{-1}$ and odds of
$10^{75}$ compared to the base-model, and (ii) $N$ discrete positive jumps in
$\epsilon_{\mathrm{p}}$ with very similar odds to the linear
$\epsilon_{\mathrm{p}}$-drift model. The physical mechanism explaining this
behaviour is unclear, but the observation could provide a crucial probe of the
interior physics of neutron stars. We also place an upper bound on the rate at
which the precessional motion is damped, and translate this into a bound on a
dissipative mutual friction-type coupling between the star's crust and core.


title:
Implications of the Occurrence of Glitches in Pulsar Free Precession
  Candidates

abstract:
  The timing properties of radio pulsars provide a unique probe of neutron star
interiors. Recent observations have uncovered quasiperiodicities in the timing
and pulse properties of some pulsars, a phenomenon that has often been
attributed to free precession of the neutron star, with profound implications
for the distribution of superfluidity and superconductivity in the star. We
advance this program by developing consistency relations between free
precession and pulsars glitches, and we show that there are difficulties in
reconciling the two phenomena in some precession candidates. This indicates
that the precession model used here needs to be modified or some other
phenomenon is at work in producing the quasiperiodicities, or even that there
is something missing in terms of our understanding of glitches.


title: Dual-scale turbulence in filamenting laser beams at high average power

abstract:
  We investigate the self-induced turbulence of high repetition rate laser
filaments over a wide range of average powers (1 mW to 100 W) and its
sensitivity to external atmospheric turbulence. Although both
externally-imposed and self-generated turbulences can have comparable
magnitudes, they act on different temporal and spatial scales. While the former
drives the shot-to-shot motion at the millisecond time scale, the latter acts
on the 0.5 s scale. As a consequence, their effects are decoupled, preventing
beam stabilization by the thermally-induced low-density channel produced by the
laser filaments.


title: NMR lineshape of $^{29}$Si in single-crystal silicon

abstract:
  We report measurements of the NMR lineshape of 4.685\% abundant $^{29}$Si in
single-crystal silicon for four different crystallographic orientations
relative to the applied magnetic field. To avoid significant inhomogeneous
broadening, the sample crystals are immersed in a susceptibility matched liquid
and the proton NMR lineshape in the liquid is used to measure the residual
susceptibility mismatch and to shim the applied field. The observed lineshapes
are in good agreement with disorder-averaged spin dynamics simulations
performed on a $4 \times 4 \times 4$ unit cell lattice with periodic boundary
conditions. The splitting of resolved doublet features is used to measure the
asymmetry $\Delta J$ of the nearest-neighbor indirect dipole or J-coupling
tensor, with the result $\Delta J=90\pm20$ Hz. All resolved doublets can be
identified with specific nearest and next-nearest neighbor isolated spin pairs
that occur in the disorder ensemble.


title: Characterization and control of ZnGeN2 cation lattice ordering

abstract:
  ZnGeN2 and other heterovalent ternary semiconductors have important potential
applications in optoelectronics, but ordering of the cation sublattice, which
can affect the band gap, lattice parameters, and phonons, is not yet well
understood. Here the effects of growth and processing conditions on the
ordering of the ZnGeN2 cation sublattice were investigated using x-ray
diffraction and Raman spectroscopy. Polycrystalline ZnGeN2 was grown by
exposing solid Ge to Zn and NH3 vapors at temperatures between 758 degree C and
914 degree C. Crystallites tended to be rod-shaped, with growth rates higher
along the c-axis. The degree of ordering, from disordered, wurtzite-like x-ray
diffraction spectra to orthorhombic, with space group Pna21, increased with
increasing growth temperature, as evidenced by the appearance of superstructure
peaks and peak splittings in the diffraction patterns. Annealing disordered,
low-temperature-grown ZnGeN2 at 850 degree C resulted in increased cation
ordering. Growth of ZnGeN2 on a liquid Sn-Ge-Zn alloy at 758 degree C showed an
increase in the tendency for cation ordering at a lower growth temperature, and
resulted in hexagonal platelet-shaped crystals. The trends shown here may help
to guide understanding of the synthesis and characterization of other
heterovalent ternary nitride semiconductors as well as ZnGeN2.


title:
Enriched TeO$_2$ bolometers with active particle discrimination: towards
  the CUPID experiment

abstract:
  We present the performances of two 92% enriched $^{130}$TeO$_2$ crystals
operated as thermal bolometers in view of a next generation experiment to
search for neutrinoless double beta decay of $^{130}$Te. The crystals, 435 g
each, show an energy resolution, evaluated at the 2615 keV $\gamma$-line of
$^{208}$Tl, of 6.5 and 4.3 keV FWHM. The only observable internal radioactive
contamination arises from $^{238}$U (15 and 8 $\mu$Bq/kg, respectively). The
internal activity of the most problematic nuclei for neutrinoless double beta
decay, $^{226}$Ra and $^{228}$Th, are both evaluated as $<$3.1 $\mu$Bq/kg for
one crystal and $<$2.3 $\mu$Bq/kg for the second. Thanks to the readout of the
weak Cherenkov light emitted by $\beta/\gamma$ particles by means of
Neganov-Luke bolometric light detectors we were able to perform an
event-by-event identification of $\beta/\gamma$ events with a 95% acceptance
level, while establishing a rejection factor of 98.21% and 99.99% for $\alpha$
particles.


title:
Sparse Channel Estimation for Massive MIMO with 1-bit Feedback per
  Dimension

abstract:
  In massive multiple-input multiple-output (MIMO) systems, acquisition of the
channel state information at the transmitter side (CSIT) is crucial. In this
paper, a practical CSIT estimation scheme is proposed for frequency division
duplexing (FDD) massive MIMO systems. Specifically, each received pilot symbol
is first quantized to one bit per dimension at the receiver side and then the
quantized bits are fed back to the transmitter. A joint one-bit compressed
sensing algorithm is implemented at the transmitter to recover the channel
matrices. The algorithm leverages the hidden joint sparsity structure in the
user channel matrices to minimize the training and feedback overhead, which is
considered to be a major challenge for FDD systems. Moreover, the one-bit
compressed sensing algorithm accurately recovers the channel directions for
beamforming. The one-bit feedback mechanism can be implemented in practical
systems using the uplink control channel. Simulation results show that the
proposed scheme nearly achieves the maximum output signal-to-noise-ratio for
beamforming based on the estimated CSIT.


title:
Direct and inverse scattering problem by an unbounded rough interface
  with buried obstacles

abstract:
  In this paper, we consider the direct and inverse problem of scattering of
time-harmonic waves by an unbounded rough interface with a buried impenetrable
obstacle. We first study the well-posedness of the direct problem with a local
source by the variational method; the well-posedness result is then extended to
scattering problems induced by point source waves (PSWs) and hyper-singular
point source waves (HSPSWs). For PSW or HSPSW incident waves, the induced total
field admits a uniformly bounded estimate in any compact subset far from the
source position. Moreover, we show that the scattered field due to HSPSWs can
be approximated by the scattered fields due to PSWs. With these properties and
a novel reciprocity relation of the total field, we prove that the rough
surface and the buried obstacle can be uniquely determined by the scattered
near-field data measured only on a line segment above the rough surface. The
proof substantially relies upon constructing a well-posed interior transmission
problem for the Helmholtz equation.


title: Exact Electromagnetic Response of Landau Level Electrons

abstract:
  We present a simple method that allows to calculate the electromagnetic
response of non-interacting electrons in strong magnetic field to arbitrary
order in the gradients of external electric and magnetic fields. We illustrate
the method on both non-relativistic and massless Dirac electrons filling $N$
Landau levels. First, we derive an exact relation between the electromagnetic
response of the non-relativistic and Dirac electrons in the lowest Landau
level. Next, we obtain a closed form expression for the polarization operator
in the large $N$ (or weak magnetic field) limit. We explicitly show that in the
large $N$ limit the random phase approximation (RPA) computation of the
polarization tensor agrees - in leading and sub-leading order in $N$ - with a
Fermi liquid computation to {\it all} orders in the gradient expansion and for
arbitrary value of the $\mathrm{g}$-factor. Finally, we show that in the large
$N$ limit the non-relativistic polarization tensor agrees with Dirac's in the
leading and sub-leading orders in $N$, provided that Berry phase of the Dirac
cone is taken into account via replacement $N\longrightarrow N+\frac{1}{2}$.


title:
Enhancing Secrecy with Multi-Antenna Transmission in Millimeter Wave
  Vehicular Communication Systems

abstract:
  Millimeter wave (mmWave) vehicular communication systems will provide an
abundance of bandwidth for the exchange of raw sensor data and support
driver-assisted and safety-related functionalities. Lack of secure
communication links, however, may lead to abuses and attacks that jeopardize
the efficiency of transportation systems and the physical safety of drivers. In
this paper, we propose two physical layer (PHY) security techniques for
vehicular mmWave communication systems. The first technique uses multiple
antennas with a single RF chain to transmit information symbols to a target
receiver and noise-like signals in non-receiver directions. The second
technique uses multiple antennas with a few RF chains to transmit information
symbols to a target receiver and opportunistically inject artificial noise in
controlled directions, thereby reducing interference in vehicular environments.
Theoretical and numerical results show that the proposed techniques provide
higher secrecy rate when compared to traditional PHY security techniques that
require digital or more complex antenna architectures.


title:
Transfer from Simulation to Real World through Learning Deep Inverse
  Dynamics Model

abstract:
  Developing control policies in simulation is often more practical and safer
than directly running experiments in the real world. This applies to policies
obtained from planning and optimization, and even more so to policies obtained
from reinforcement learning, which is often very data demanding. However, a
policy that succeeds in simulation often doesn't work when deployed on a real
robot. Nevertheless, often the overall gist of what the policy does in
simulation remains valid in the real world. In this paper we investigate such
settings, where the sequence of states traversed in simulation remains
reasonable for the real world, even if the details of the controls are not, as
could be the case when the key differences lie in detailed friction, contact,
mass and geometry properties. During execution, at each time step our approach
computes what the simulation-based control policy would do, but then, rather
than executing these controls on the real robot, our approach computes what the
simulation expects the resulting next state(s) will be, and then relies on a
learned deep inverse dynamics model to decide which real-world action is most
suitable to achieve those next states. Deep models are only as good as their
training data, and we also propose an approach for data collection to
(incrementally) learn the deep inverse dynamics model. Our experiments shows
our approach compares favorably with various baselines that have been developed
for dealing with simulation to real world model discrepancy, including output
error control and Gaussian dynamics adaptation.


title:
Quantization of the ${\rm AdS}_3$ Superparticle on ${\rm
  OSP}(1|2)^2/{\rm SL}(2,\mathbb{R})$

abstract:
  We analyze ${\rm AdS}_3$ superparticle dynamics on the coset ${\rm OSP}(1|2)
\times {\rm OSP}(1|2)/{\rm SL}(2,\mathbb{R})$. The system is quantized in
canonical coordinates obtained by gauge invariant Hamiltonian reduction. The
left and right Noether charges of a massive particle are parametrized by
coadjoint orbits of a timelike element of $\frak{osp}(1|2)$. Each chiral sector
is described by two bosonic and two fermionic canonical coordinates
corresponding to a superparticle with superpotential $W=q-m/q$, where $m$ is
the particle mass. Canonical quantization then provides a quantum realization
of $\frak{osp}(1|2)\oplus\frak{osp}(1|2)$. For the massless particle the chiral
charges lie on the coadjoint orbit of a nilpotent element of $\frak{osp}(1|2)$
and each of them depends only on one real fermion, which demonstrates the
underlying $\kappa$-symmetry. These remaining left and right fermionic
variables form a canonical pair and the system is described by four bosonic and
two fermionic canonical coordinates. Due to conformal invariance of the
massless particle, the $\frak{osp}(1|2)\oplus\frak{osp} (1|2)$ extends to the
corresponding superconformal algebra $\frak{osp}(2|4)$. Its 19 charges are
given by all real quadratic combinations of the canonical coordinates, which
trivializes their quantization.


title:
Periodic metallic stepped-slits for entire transmission of optical wave
  and efficient transmission of terahertz wave

abstract:
  Metallic structures with periodic array of slits are well-known to lead to
extraordinary power transmission, when slits have dimensions much less than the
wavelength of incident optical wave. Excellent power transmission originates
from surface waves excited by incident transverse magnetic wave. Here we show
that metallic structure with array of stepped-slits can transmit power of
incident wave into the substrate at desired optical frequency entirely and
simultaneously in terahertz frequency band by 70%, for In0.53Ga0.47As
substrate. Transmitted power of the proposed structure is studied both in a
closed-form by an analytical model as well as numerically by finite element
method. It is found that with the increase of field intensity in the substrate,
structure with array of stepped-slits (as opposed to uniform-slits) favorably
has no reduction of frequency range at maximum transmitted power.


title:
A Review of Mathematical Models for Muscular Dystrophy: A Systems
  Biology Approach

abstract:
  Muscular dystrophy (MD) describes generalized progressive muscular weakness
due to the wasting of muscle fibers. The progression of the disease is affected
by known immunological and mechanical factors, and possibly other unknown
mechanisms. These dynamics have begun to be elucidated in the last two decades.
This article reviews mathematical models of MD that characterize molecular and
cellular components implicated in MD progression. A biological background for
these processes is also presented. Molecular effectors that contribute to MD
include mitochondrial bioenergetics and genetic factors; both drive cellular
metabolism, communication and signaling. These molecular events leave cells
vulnerable to mechanical stress which can activate an immunological cascade
that weakens cells and surrounding tissues. This review article lays the
foundation for a systems biology approach to study MD progression.


title:
Supermarket Queueing System in the Heavy Traffic Regime. Short Queue
  Dynamics

abstract:
  We consider a queueing system with $n$ parallel queues operating according to
the so-called "supermarket model" in which arriving customers join the shortest
of $d$ randomly selected queues. Assuming rate $n\lambda_{n}$ Poisson arrivals
and rate $1$ exponentially distributed service times, we consider this model in
the heavy traffic regime, described by $\lambda_{n}\uparrow 1$ as $n\to\infty$.
We give a simple expectation argument establishing that majority of queues have
steady state length at least $\log_d(1-\lambda_{n})^{-1} - O(1)$ with
probability approaching one as $n\rightarrow\infty$, implying the same for the
steady state delay of a typical customer.
  Our main result concerns the detailed behavior of queues with length smaller
than $\log_d(1-\lambda_{n})^{-1}-O(1)$. Assuming $\lambda_{n}$ converges to $1$
at rate at most $\sqrt{n}$, we show that the dynamics of such queues does not
follow a diffusion process, as is typical for queueing systems in heavy
traffic, but is described instead by a deterministic infinite system of linear
differential equations, after an appropriate rescaling. The unique fixed point
solution of this system is shown explicitly to be of the form
$\pi_{1}(d^{i}-1)/(d-1), i\ge 1$, which we conjecture describes the steady
state behavior of the queue lengths after the same rescaling. Our result is
obtained by combination of several technical ideas including establishing the
existence and uniqueness of an associated infinite dimensional system of
non-linear integral equations and adopting an appropriate stopped process as an
intermediate step.


title: Noncommutative potential theory

abstract:
  We propose to view hermitian metrics on trivial holomorphic vector bundles
$E\to\Omega$ as noncommutative analogs of functions defined on the base
$\Omega$, and curvature as the notion corresponding to the Laplace operator or
$\partial\overline\partial$. We discuss noncommutative generalizations of basic
results of ordinary potential theory, mean value properties, maximum principle,
Harnack inequality, and the solvability of Dirichlet problems.


title:
Improved Parallel Construction of Wavelet Trees and Rank/Select
  Structures

abstract:
  Existing parallel algorithms for wavelet tree construction have a work
complexity of $O(n\log\sigma)$. This paper presents parallel algorithms for the
problem with improved work complexity. Our first algorithm is based on parallel
integer sorting and has either $O(n\log\log n\lceil\log\sigma/\sqrt{\log
n\log\log n}\rceil)$ work and polylogarithmic depth, or
$O(n\lceil\log\sigma/\sqrt{\log n}\rceil)$ work and sub-linear depth. We also
describe another algorithm that has $O(n\lceil\log\sigma/\sqrt{\log n} \rceil)$
work and $O(\sigma+\log n)$ depth. We then show how to use similar ideas to
construct variants of wavelet trees (arbitrary-shaped binary trees and multiary
trees) as well as wavelet matrices in parallel with lower work complexity than
prior algorithms. Finally, we show that the rank and select structures on
binary sequences and multiary sequences, which are stored on wavelet tree
nodes, can be constructed in parallel with improved work bounds, matching those
of the best existing sequential algorithms for constructing rank and select
structures.


title: Polynomial methods for Procedural Terrain Generation

abstract:
  A new method is presented, allowing for the generation of 3D terrain and
texture from coherent noise. The method is significantly faster than prevailing
fractal brownian motion approaches, while producing results of equivalent
quality. The algorithm is derived through a systematic approach that
generalizes to an arbitrary number of spatial dimensions and gradient
smoothness. The results are compared, in terms of performance and quality, to
fundamental and efficient gradient noise methods widely used in the domain of
fast terrain generation: Perlin noise and OpenSimplex noise. Finally, to
objectively quantify the degree of realism of the results, a fractal analysis
of the generated landscapes is performed and compared to real terrain data.


title: Nucleon parton distributions in a light-front quark model

abstract:
  Continuing with our analysis of parton distributions in the nucleon, we
extend our light-front quark model in order to obtain both the helicity
independent and helicity dependent parton distributions, analytically matching
the results of global fits at the initial scale $\mu \sim 1$ GeV, and which
also contain the correct Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution.
We also calculate the transverse parton, Wigner and Husimi distributions from a
unified point of view, using our light-front wave functions and expressing them
in terms of the parton distributions $q_v(x)$ and $\delta q_v(x)$. Our results
are very relevant for the current and future program of the COMPASS experiment
at SPS (CERN).


title: Cooperative Strategies for Wireless-Powered Communications: An Overview

abstract:
  Radio frequency (RF) energy transfer and harvesting has been intensively
studied recently as a promising approach to significantly extend the lifetime
of energy-constrained wireless networks. This technique has a great potential
to provide relatively stable and continuous RF energy to devices wirelessly; it
thus opened a new research paradigm, termed wireless-powered communication
(WPC), which has raised many new research opportunities with wide applications.
Among these, the design and analysis of cooperative schemes towards efficient
WPC have attracted tremendous research interests nowadays. This article
provides an overview of various cooperative strategies for WPC, with particular
emphasis on relaying protocols for wireless-powered cooperative communications,
cooperative spectrum sharing schemes for cognitive wireless-powered networks,
and cooperative jamming strategies towards wireless-powered secure
communications. We also identify several interesting research directions in
this area before concluding this article.


title: Explicit Hilbert Irreducibility

abstract:
  Let $P(T,X)$ be an irreducible polynomial in two variables with rational
coefficients. It follows from Hilbert's Irreducibility Theorem that for most
rational numbers $t$ the specialized polynomial $P(t,X)$ is irreducible and has
the same Galois group as $P$. We discuss here a method for obtaining an
explicit description of the set of exceptional numbers $t$, i.e., those for
which $P(t,X)$ is either reducible or has a different Galois group than $P$. To
illustrate the method we determine the exceptional specializations of two
polynomials of degrees four and six.


title: Tracing the origin of the AGN fuelling reservoir in MCG--6-30-15

abstract:
  The active galaxy MCG--6-30-15 has a 400 pc diameter stellar kinematically
distinct core, counter-rotating with respect to the main body of the galaxy.
Our previous high spatial resolution (0".1) H-band observations of this galaxy
mapped the stellar kinematics and [Fe II] 1.64 {\mu}m gas dynamics though
mainly restricted to the spatial region of the counter-rotating core. In this
work we probe the stellar kinematics on a larger field-of-view and determine
the ionised and molecular gas dynamics to study the formation of the
counter-rotating core and the implications for AGN fuelling. We present
integral field spectroscopy observations with SINFONI in the H and K-bands in
the central 1.2 kpc and with VIMOS HR-blue in the central 4 kpc of the galaxy.
Ionised gas outflows of v ~ 100 km/s are traced by the [Ca VIII] 2.32 {\mu}m
coronal line and extend out to at least a radius of r ~ 140 pc. The molecular
gas, traced by the H2 2.12 {\mu}m emission is also counter rotating with
respect to the main body of the galaxy, indicating that the formation of the
distinct core was associated with inflow of external gas into the centre of
MCG--6-30-15. The molecular gas traces the available gas reservoir for AGN
fuelling and is detected as close as r ~ 50 - 100 pc. External gas accretion is
able to significantly replenish the fuelling reservoir suggesting that the
event that formed the counter-rotating core was also the main mechanism
providing gas for AGN fuelling.


title: Gamma-ray emission from galaxy cluster outskirts versus radio relics

abstract:
  Galaxy cluster peripheries provide important information on the nature of
ICM/IGM linkage. In this paper we consider potential future observations in the
gamma-ray domain at cluster edges involving the radio relic phenomenon.
  We focus on the spectral signature of gamma radiation that should be evident
in the energy range of Fermi--LAT, i.e. $\gtrsim 10^{-1}$ GeV and the CTA
energy range $\sim$ $ 10^{2}$ GeV. The spectral signature results from a
comparable gamma-ray flux due to the IC and $ \pi ^{0} $ decay on the edge of
the cluster, and its spectral position is a function of the magnetic field and
relative efficiency of the acceleration of protons and electrons. We aim to
draw attention to the dependence of the gamma-ray structure on the magnetic
field value.
  As an example, we carried out analyses of two types of non-thermal diffuse
radio emission: the radio relic of A 2256 and the radio halo of Coma cluster.
We suggest that in both cases the expected spatially correlated gamma-ray
spectrum should have a characteristic structure that depends on the strength of
the local magnetic field. In both of the clusters we calculated the combined
flux of gamma radiation from the actual observational values of the used
observables.
  The revealed spectral dependence on the magnetic field would allow us to
relate the future spectral observations, in particular the position of the
gamma-ray signature, to the value of the magnetic field in the border area
between galaxy clusters and their connecting filaments, possibly constraining
the estimated relative efficiency of particle acceleration at the edge of the
cluster.


title:
A Tale of Two Emergences: Sunrise II Observations of Emergence Sites in
  a Solar Active Region

abstract:
  In June 2013, the two scientific instruments onboard the second Sunrise
mission witnessed, in detail, a small-scale magnetic flux emergence event as
part of the birth of an active region. The Imaging Magnetograph Experiment
(IMaX) recorded two small (~5 arcsec) emerging flux patches in the polarized
filtergrams of a photospheric Fe I spectral line. Meanwhile, the Sunrise Filter
Imager (SuFI) captured the highly dynamic chromospheric response to the
magnetic fields pushing their way through the lower solar atmosphere. The
serendipitous capture of this event offers a closer look at the inner workings
of active region emergence sites. In particular, it reveals in meticulous
detail how the rising magnetic fields interact with the granulation as they
push through the Sun's surface, dragging photospheric plasma in their upward
travel. The plasma that is burdening the rising field slides along the field
lines, creating fast downflowing channels at the footpoints. The weight of this
material anchors this field to the surface at semi-regular spatial intervals,
shaping it in an undulatory fashion. Finally, magnetic reconnection enables the
field to release itself from its photospheric anchors, allowing it to continue
its voyage up to higher layers. This process releases energy that lights up the
arch-filament systems and heats the surrounding chromosphere.


title:
On the uniqueness of $L$-fuzzy sets in the representation of families of
  sets

abstract:
  This paper deals with the uniqueness of $L$-fuzzy sets in the representation
of a given family of subsets of nonempty set. It first shows a formula of the
number of $L$-fuzzy sets whose collection of cuts coincides with a given family
of subsets of a nonempty set, and then provides a necessary and sufficient
condition under which such $L$-fuzzy sets are unique.


title:
Stable Band-Gaps in Phononic Crystals by Harnessing Hyperelastic
  Transformation Media

abstract:
  The band structure in phononic crystals (PCs) is usually affected by the
deformations of their soft components. In this work, hyperelastic
transformation media is proposed to be integrated in the PCs'design, to achieve
stable elastic band-gaps which is independent with finite mechanical
deformations. For a one-dimensional (1D) PC, we demonstrate the semi-linear
soft component can keep all elastic wave bands unchanged with the external
deformation field. While for neo-Hookean soft component, only S-wave bands can
be precisely retained. The change of the P-wave bands can be predicted by using
a lumped mass method. Numerical simulations are performed to validate our
theory predictions and the robustness of the proposed PCs.


title:
Comparative study of High-speed Linux TCP Variants over High-BDP
  Networks

abstract:
  Transmission Control Protocol (TCP) has been profusely used by most of
internet applications. Since 1970s, several TCP variants have been developed in
order to cope with the fast increasing of network capacities especially in high
Bandwidth Delay Product (high-BDP) networks. In these TCP variants, several
approaches have been used, some of these approaches have the ability to
estimate available bandwidths and some react based on network loss and/or delay
changes. This variety of the used approaches arises many consequent problems
with different levels of dependability and accuracy. Indeed, a particular TCP
variant which is proper for wireless networks, may not fit for high-BDP wired
networks and vice versa. Therefore, it is necessary to conduct a comparison
between the high-speed TCP variants that have a high level of importance
especially after the fast growth of networks bandwidths. In this paper,
high-speed TCP variants, that are implemented in Linux and available for
research, have been evaluated using NS2 network simulator. This performance
evaluation presents the advantages and disadvantages of these TCP variants in
terms of throughput, loss-ratio and fairness over high-BDP networks. The
results reveal that, CUBIC and YeAH overcome the other highspeed TCP variants
in different cases of buffer size. However, they still require more improvement
to extend their ability to fully utilize the high-speed bandwidths, especially
when the applied buffer is near-zero or less than the BDP of the link.


title: Pattern avoidance and fiber bundle structures on Schubert varieties

abstract:
  We give a permutation pattern avoidance criteria for determining when the
projection map from the flag variety to a Grassmannian induces a fiber bundle
structure on a Schubert variety. In particular, we introduce the notion of a
split pattern and show that a Schubert variety has such a fiber bundle
structure if and only if the corresponding permutation avoids the split
patterns 3|12 and 23|1. Continuing, we show that a Schubert variety is an
iterated fiber bundle of Grassmannian Schubert varieties if and only if the
corresponding permutation avoids (non-split) patterns 3412, 52341, and 635241.
This extends a combined result of Lakshmibai-Sandhya, Ryan, and Wolper who
prove that Schubert varieties whose permutation avoids the "smooth" patterns
3412 and 4231 are iterated fiber bundles of smooth Grassmannian Schubert
varieties.


title: Thin-sheet creation and threshold pressures in drop splashing

abstract:
  A liquid drop impacting a smooth solid substrate splashes by emitting a thin
liquid sheet from near the contact line of the spreading liquid. This sheet is
lifted from the substrate and ultimately breaks apart. Surprisingly, the splash
is caused by the ambient gas, whose properties dictate when and if the sheet is
created. Here I focus on two aspects of this process. Using high-speed imaging
I find that the time of thin-sheet creation displays a different quantitative
dependence on air pressure if the sheet is created during the early stages of
spreading, rather than when the liquid has already spread to a large radius.
This result sheds light on previously observed impact velocity regimes.
Additionally, by measuring impacts of drops on surfaces comprised of both rough
and smooth regions, I identify a new threshold velocity that limits the times
at which the thin sheet can be created. This velocity determines the threshold
pressure below which splashing is suppressed.


title: Bounded Topological Speedups

abstract:
  This paper explores the range of bounded speedups in the topological
category. Bounded speedups represent both a strengthening of topological
speedups as defined in [A 16] and a generalization of powers of a
transformation. Here we show that bounded speedups preserve the structure of
two classical minimal Cantor systems. Specifically, a minimal bounded speedup
of an odometer is a conjugate odometer, and a minimal bounded speedup of a
primitive substitution is again a primitive substitution, though it is never
conjugate to the original substitution system. Further, we give bounds on the
topological entropy of bounded speedups, and in special cases we compute the
topological entropy of bounded speedups.


title: Gaussian quantum metrology and space-time probes

abstract:
  In this thesis we focus on Gaussian quantum metrology in the phase-space
formalism and its applications in quantum sensing and the estimation of
space-time parameters. We derive new formulae for the optimal estimation of
multiple parameters encoded into Gaussian states. We discuss the discontinuous
behavior of the figure of merit - the quantum Fisher information. Using derived
expressions we devise a practical method of finding optimal probe states for
the estimation of Gaussian channels and we illustrate this method on several
examples. We show that the temperature of a probe state affects the estimation
generically and always appears in the form of four multiplicative factors. We
also discuss how well squeezed thermal states perform in the estimation of
space-time parameters. Finally we study how the estimation precision changes
when two parties exchanging a quantum state with the encoded parameter do not
share a reference frame. We show that using a quantum reference frame could
counter this effect.


title: Weyl Gravity Revisited

abstract:
  The on shell equivalence of first order and second order formalisms for the
Einstein-Hilbert action does not hold for those actions quadratic in curvature.
It would seem that by considering the connection and the metric as independent
dynamical variables, there are no quartic propagators for any dynamical
variable. This suggests that it is possible to get both renormalizability and
unitarity along these lines. We have studied a particular instance of those
theories, namely Weyl gravity. Although the ground state of this system is
difficult to analyze, we have been able to study the physical effects of some
external sources.


title: Geometry of black hole spacetimes

abstract:
  These notes, based on lectures given at the summer school on Asymptotic
Analysis in General Relativity, collect material on the Einstein equations, the
geometry of black hole spacetimes, and the analysis of fields on black hole
backgrounds. The Kerr model of a rotating black hole in vacuum is expected to
be unique and stable. The problem of proving these fundamental facts provides
the background for the material presented in these notes.
  Among the many topics which are relevant for the uniqueness and stability
problems are the theory of fields on black hole spacetimes, in particular for
gravitational perturbations of the Kerr black hole, and more generally, the
study of nonlinear field equations in the presence of trapping. The study of
these questions requires tools from several different fields, including
Lorentzian geometry, hyperbolic differential equations and spin geometry, which
are all relevant to the black hole stability problem.


title: Capacity bounds for distributed storage

abstract:
  One of the primary objectives of a distributed storage system is to reliably
store large amounts of source data for long durations using a large number $N$
of unreliable storage nodes, each with $c$ bits of storage capacity. Storage
nodes fail randomly over time and are replaced with nodes of equal capacity
initialized to zeroes, and thus bits are erased at some rate $E$. To maintain
recoverability of the source data, a repairer continually reads data over a
network from nodes at a rate $R$, and generates and writes data to nodes based
on the read data.
  The distributed storage source data capacity is the maximum amount of source
data that can be reliably stored for long periods of time. We prove the
distributed storage source data capacity asymptotically approaches
$\left(1-\frac{E}{2 \cdot R}\right) \cdot N \cdot c$ as $N$ and $R$ grow. This
equation expresses a fundamental trade-off between network traffic and storage
overhead to reliably store source data.


title:
Clinical and Educational Applications of LIVEIA: An Immersive
  Visualization Environment

abstract:
  The association between light and psychological states has a long history and
permeates our language. LIVEIA (Light-based Immersive Visualization Environment
for Imaginative Actualization) is a new immersive, interactive technology that
uses physical light as a metaphor for visualizing peoples' inner lives and
relationships. This paper outlines its educational value, as a tool for
understanding and explaining aspects of how people think and interact, and its
potential therapeutic value as a form of art therapy in which the artwork has
straightforwardly interpretable symbolic meanings.


title: Quantum automata cannot detect biased coins, even in the limit

abstract:
  Aaronson and Drucker (2011) asked whether there exists a quantum finite
automaton that can distinguish fair coin tosses from biased ones by spending
significantly more time in accepting states, on average, given an infinite
sequence of tosses. We answer this question negatively.


title:
Large magnetic anisotropy predicted for rare-earth free Fe16-xCoxN2
  alloys

abstract:
  Structures and magnetic properties of Fe16-xCoxN2 are studied using adaptive
genetic algorithm and first-principles calculations. We show that substituting
Fe by Co in Fe16N2 with Co/Fe ratio smaller than 1 can greatly improve the
magnetic anisotropy of the material. The magnetocrystalline anisotropy energy
from first-principles calculations reaches 3.18 MJ/m3 (245.6 {\mu}eV per metal
atom) for Fe12Co4N2, much larger than that of Fe16N2 and is one of the largest
among the reported rare-earth free magnets. From our systematic crystal
structure searches, we show that there is a structure transition from
tetragonal Fe16N2 to cubic Co16N2 in Fe16-xCoxN2 as the Co concentration
increases, which can be well explained by electron counting analysis. Different
magnetic properties between the Fe-rich (x < 8) and Co-rich (x > 8) Fe16-xCoxN2
is closely related to the structural transition.


title:
Search for anomalous Wtb couplings and flavour-changing neutral currents
  in t-channel single top quark production in pp collisions at sqrt(s) = 7 and
  8 TeV

abstract:
  Single top quark events produced in the t channel are used to set limits on
anomalous Wtb couplings and to search for top quark flavour-changing neutral
current (FCNC) interactions. The data taken with the CMS detector at the LHC in
proton-proton collisions at sqrt(s) = 7 and 8 TeV correspond to integrated
luminosities of 5.0 and 19.7 inverse femtobarns, respectively. The analysis is
performed using events with one muon and two or three jets. A Bayesian neural
network technique is used to discriminate between the signal and backgrounds,
which are observed to be consistent with the standard model prediction. The 95%
confidence level (CL) exclusion limits on anomalous right-handed vector, and
left- and right-handed tensor Wtb couplings are measured to be |f[V]^R| < 0.16,
|f[T]^L| < 0.057, and -0.049 < f[T]^R < 0.048, respectively. For the FCNC
couplings kappa[tug] and kappa[tcg], the 95% CL upper limits on coupling
strengths are |kappa[tug]|/Lambda < 4.1E-3 TeV-1 and |kappa[tcg]|/Lambda <
1.8E-2 TeV-1, where Lambda is the scale for new physics, and correspond to
upper limits on the branching fractions of 2.0E-5 and 4.1E-4 for the decays t
to ug and t to cg, respectively.


title:
Classical and \textcolor{blue}{Quantum} Field-Theoretical approach to
  the non-linear q-Klein-Gordon Equation

abstract:
  \color{blue}{In the wake of efforts made in [EPL {\bf 97}, 41001 (2012)] and
[J. Math. Phys. {\bf 54}, 103302 (2913)], we extend them here by developing the
conventional Lagrangian treatment of a classical field theory (FT) to the
q-Klein-Gordon equation advanced in [Phys. Rev. Lett. {\bf 106}, 140601 (2011)]
and [J. Math. Phys. {\bf 54}, 103302 (2913)], and the quantum theory
corresponding to $q=\frac {3} {2}$. This makes it possible to generate a
putative conjecture regarding black matter. Our theory reduces to the usual FT
for $q\rightarrow 1$.}

categories: hep-th cond-mat.stat-mech math-ph math.MP


title: The Multivariable moment problems and recursive relations

abstract:
  Let $\beta \equiv \{ \beta_\mathbf{i} \}_{\mathbf{i} \in \mathbb{Z}_+^d}$ be
a $d$-dimensional multisequence. Curto and Fialkow, have shown that if the
infinite moment matrix $M(\beta)$ is finite-rank positive semidefinite, then
$\beta$ has a unique representing measure, which is $rank M(\beta)$-atomic.
Further, let $\beta^{(2n)} \equiv \{ \beta_\mathbf{i} \}_{\mathbf{i} \in
\mathbb{Z}_+^d, \mid \mathbf{i} \mid \leq 2n}$ be a given truncated
multisequence, with associated moment matrix $M(n)$ and $rank M(n)=r$, then
$\beta^{(2n)}$ has an $r$-atomic representing measure $\mu$ supported in the
semi-algebraic set $K=\{ (t_1, \ldots, t_d) \in \mathbb{R}^d : q_j(t_1, \ldots,
t_d) \geq 0, 1\leq j\leq m \}$, where $q_j \in \mathbb{R}[t_1, \ldots, t_d]$,
if $M(n)$ admits a positive rank-preserving extension $M(n+1)$ and the
localizing matrices $M_{q_j}(n +[\frac{\deg q_j +1}{2}])$ are positive
semidefinite; moreover, $\mu$ has precisely $rank M(n) - rank M_{q_j}(n
+[\frac{\deg q_j +1}{2}])$ atoms in $\mathcal{Z}(q_j) \equiv \{ t\in
\mathbb{R}^d: q_j(t)=0 \}$. In this paper, we show that every truncated moment
sequence $\beta^{(2n)}$ is a subsequence of an infinite recursively generated
multisequence, we investigate such sequences to give an alternative proof of
Curto-Fialkow's results and also to obtain a new interesting results.