title: Optical manipulation of a magnon-photon hybrid system

abstract:
  We demonstrate an all-optical method for manipulating the magnetization in a
1-mm YIG (yttrium-iron-garnet) sphere placed in a $\sim0.17\,$T uniform
magnetic field. An harmonic of the frequency comb delivered by a multi-GHz
infrared laser source is tuned to the Larmor frequency of the YIG sphere to
drive magnetization oscillations, which in turn give rise to a radiation field
used to thoroughly investigate the phenomenon. The radiation damping issue that
occurs at high frequency and in the presence of highly magnetizated materials,
has been overcome by exploiting magnon-photon strong coupling regime in
microwave cavities. Our findings demonstrate an effective technique for
ultrafast control of the magnetization vector in optomagnetic materials via
polarization rotation and intensity modulation of an incident laser beam. We
eventually get a second-order susceptibility value of $\sim10^{-7}$ cm$^2$/MW
for single crystal YIG.


title:
$p$-adic Distance, Finite Precision and Emergent Superdeterminism: A
  Number-Theoretic Consistent-Histories Approach to Local Quantum Realism

abstract:
  Although the notion of superdeterminism can, in principle, account for the
violation of the Bell inequalities, this potential explanation has been roundly
rejected by the quantum foundations community. The arguments for rejection, one
of the most substantive coming from Bell himself, are critically reviewed. In
particular, analysis of Bell's argument reveals an implicit unwarranted
assumption: that the Euclidean metric is the appropriate yardstick for
measuring distances in state space. Bell's argument is largely negated if this
yardstick is instead based on the alternative $p$-adic metric. Such a metric,
common in number theory, arises naturally when describing chaotic systems which
evolve precisely on self-similar invariant sets in their state space. A
locally-causal realistic model of quantum entanglement is developed, based on
the premise that the laws of physics ultimately derive from an invariant-set
geometry in the state space of a deterministic quasi-cyclic mono-universe.
Based on this, the notion of a complex Hilbert vector is reinterpreted in terms
of an uncertain selection from a finite sample space of states, leading to a
novel form of `consistent histories' based on number-theoretic properties of
the transcendental cosine function. This leads to novel realistic
interpretations of position/momentum non-commutativity, EPR, the Bell Theorem
and the Tsirelson bound. In this inherently holistic theory - neither
conspiratorial, retrocausal, fine tuned nor nonlocal - superdeterminism is not
invoked by fiat but is emergent from these `consistent histories'
number-theoretic constraints. Invariant set theory provides new perspectives on
many of the contemporary problems at the interface of quantum and gravitational
physics, and, if correct, may signal the end of particle physics beyond the
Standard Model.


title: The Helmholtz theorem and retarded fields

abstract:
  Textbooks frequently use the Helmholtz theorem to derive expressions for the
electrostatic and magnetostatic fields but they do not usually apply this
theorem to derive expressions for the time-dependent electric and magnetic
fields, even when there is no formal objection to doing so because the proof of
the theorem does not involve time derivatives but only spatial derivatives.
Here we address the question as to whether the Helmholtz theorem is useful to
derive expressions for the fields of Maxwell's equations. We show that when
this theorem is applied to Maxwell's equations we obtain instantaneous
expressions of the electric and magnetic fields, which are formally correct but
of little practical usefulness. We then discuss two generalizations of the
theorem which are shown to be useful to derive the retarded fields.


title:
N-P-N Bipolar Action in Junctionless Nanowire TFET: Physical Operation
  of a Modified Current Mechanism for Low Power Applications

abstract:
  In this paper we study the device physics of a technique for realizing an
n-p-n bipolar transistor action in the source side of a junctionless nanowire
tunneling FET (BJN-TFET). In the on-state, tunneling of electrons from valence
band of the source to conduction band of the channel enhances the hole
concentration as well as the potential in the source region which drives a
built-in BJT transistor by forward biasing the base-emitter junction, with the
source acting as a p-type region. Owing to the sharp switching of the JN-TFET
and high BJT current gain, the overall performance is improved, including
favorable high on-state current (2.17*10-6 A/um), and sub 60 mV/dec
subthreshold swing (~ 50 mV/dec) at low supply voltages. This approach modifies
the current mechanism owning to the triggered BJT and makes the proposed
structure more attractive for scaling requirements in future low power
application.


title: Nonnegative autoencoder with simplified random neural network

abstract:
  This paper proposes new nonnegative (shallow and multi-layer) autoencoders by
combining the spiking Random Neural Network (RNN) model, the network
architecture typical used in deep-learning area and the training technique
inspired from nonnegative matrix factorization (NMF). The shallow autoencoder
is a simplified RNN model, which is then stacked into a multi-layer
architecture. The learning algorithm is based on the weight update rules in
NMF, subject to the nonnegative probability constraints of the RNN. The
autoencoders equipped with this learning algorithm are tested on typical image
datasets including the MNIST, Yale face and CIFAR-10 datasets, and also using
16 real-world datasets from different areas. The results obtained through these
tests yield the desired high learning and recognition accuracy. Also, numerical
simulations of the stochastic spiking behavior of this RNN auto encoder, show
that it can be implemented in a highly-distributed manner.


title: Laser fields and proxy fields

abstract:
  The convention in Atomic, Molecular, and Optical (AMO) physics of employing
the dipole approximation to describe laser-induced processes replaces four
source-free Maxwell equations governing laser fields with a single Maxwell
equation for a "proxy" field that requires a virtual source current for its
existence. Laser fields are transverse, but proxy fields are longitudinal;
there can be no gauge equivalence. The proxy field is sometimes serviceable,
but its limitations are severe. One example is the "above-threshold ionization"
(ATI) phenomenon; surprising by proxy-field understanding, but natural and
predicted in advance of observation with a laser-field method. An
often-overlooked limitation is that numerical solution of the time-dependent
Schr\"odinger equation (TDSE) is exact for proxy fields, but not for laser
fields. Acceptance of proxy-field concepts has been costly in terms of
inefficiently deployed research resources. Calculations with a nearly-40-year
old transverse-field method remain unmatched with proxy fields. The
transverse-field method is applicable in the "tunneling" domain, the
"multiphoton" domain, and, as shown here, in the low-frequency "magnetic"
domain. Attempts to introduce low-frequency magnetic field corrections into
TDSE cannot be expected to produce meaningful results. They would be based on
inappropriate Maxwell equations, a non-existent virtual source, and would
approach constant electric field properties as the field frequency declines.
Laser fields propagate at the speed of light for all frequencies; they cannot
approach a constant-field limit. Extremely strong laser fields are
unambiguously relativistic; a nonrelativistic limit that connects continuously
to the relativistic domain is simpler conceptually and mathematically than is a
theory constructed with a proxy field that is certain to fail as intensities
increase.


title: Full-Spectrum Flexible Color Printing at the Diffraction Limit

abstract:
  Color printing at the diffraction limit has been recently explored by
fabricating nanoscale plasmonic structures with electron beam lithography.
However, only a limited color range and constant intensity throughout the
structure have been demonstrated. Here we show an alternative, facile approach
relying on the direct, open-atmosphere electrohydrodynamic rapid nanodrip
printing of controlled amounts of red, green and blue (RGB) quantum dots at a
resolution of 250 nm. The narrow emission spectrum of the dots allows the
coverage of a very broad color space, exceeding standard RGB (sRGB) of modern
display devices. We print color gradients of variable intensity, which to date
could not be achieved with diffraction-limited resolution. Showcasing the
capabilities of the technology, we present a photo-realistic printed image of a
colorful parrot with a pixel size of 250 nm.


title: Implementing RBAC model in An Operating System Kernel

abstract:
  In this paper, the implementation of an operating system oriented RBAC model
is discussed. Firstly, on the basis of RBAC96 model, a new RBAC model named OSR
is presented. Secondly, the OSR model is enforced in RFSOS kernel by the way of
integrating GFAC method and Capability mechanism together. All parts of the OSR
implementation are described in detail.


title:
On the use of applying Lie-group symmetry analysis to turbulent channel
  flow with streamwise rotation

abstract:
  The study by Oberlack et al. (2006) consists of two main parts: a direct
numerical simulation (DNS) of a turbulent plane channel flow with streamwise
rotation and a preceding Lie-group symmetry analysis on the two-point
correlation equation (TPC) to analytically predict the scaling of the mean
velocity profiles for different rotation rates. We will only comment on the
latter part, since the DNS result obtained in the former part has already been
commented on by Recktenwald et al. (2009), stating that the observed mismatch
between DNS and their performed experiment is possibly due to the prescription
of periodic boundary conditions on a too small computational domain in the
spanwise direction. By revisiting the group analysis part in Oberlack et al.
(2006), we will generate more natural scaling laws describing better the mean
velocity profiles than the ones proposed. However, due to the statistical
closure problem of turbulence, this improvement is illusive. As we will
demonstrate, any arbitrary invariant scaling law for the mean velocity profiles
can be generated consistent to any higher order in the velocity correlations.
This problem of arbitrariness in invariant scaling persists even if we would
formally consider the infinite statistical hierarchy of all multi-point
correlation equations. The closure problem of turbulence simply cannot be
circumvented by just employing the method of Lie-group symmetry analysis alone:
as the statistical equations are unclosed, so are their symmetries! Hence, an a
priori prediction as how turbulence scales is thus not possible. Only a
posteriori by anticipating what to expect from numerical or experimental data
the adequate invariant scaling law can be generated through an iterative
trial-and-error process. Finally, apart from this issue, also several
inconsistencies and incorrect statements to be found in Oberlack et al. (2006)
will be pointed out.


title: $\mathcal{N} = 1$ superconformal theories with $D_N$ blocks

abstract:
  We study the chiral ring of four-dimensional superconformal field theories
obtained by wrapping M5-branes on a complex curve inside a Calabi-Yau
three-fold. We propose a field theoretic construction of all the theories found
by Bah, Beem, Bobev and Wecht by introducing new building blocks, and prove
several $\mathcal{N} = 1$ dualities featuring the latter. We match the central
charges with those computed from the M5-brane anomaly polynomial, perform the
counting of relevant operators and analyze unitarity bound violations. As a
byproduct, we compute the exact dimension of "heavy operators" obtained by
wrapping an M2-brane on the complex curve.


title: Energy helps accuracy: electroweak precision tests at hadron colliders

abstract:
  We show that high energy measurements of Drell-Yan at the LHC can serve as
electroweak precision tests. Dimension-6 operators, from the Standard Model
Effective Field Theory, modify the high energy behavior of electroweak gauge
boson propagators. Existing measurements of the dilepton invariant mass
spectrum, from neutral current Drell-Yan at 8 TeV, have comparable sensitivity
to LEP. We propose measuring the transverse mass spectrum of charged current
Drell-Yan, which can surpass LEP already with 8 TeV data. The 13 TeV LHC will
elevate electroweak tests to a new precision frontier.


title:
Towards a multi-scale understanding of the gas-star formation cycle in
  the Central Molecular Zone

abstract:
  The Central Molecular Zone (CMZ, the central 500 pc of the Milky Way)
contains the largest reservoir of high-density molecular gas in the Galaxy, but
forms stars at a rate 10-100 times below commonly-used star formation
relations. We discuss recent efforts in understanding how the nearest galactic
nucleus forms its stars. The latest models of the gas inflow, star formation,
and feedback duty cycle reproduce the main observable features of the CMZ,
showing that star formation is episodic and that the CMZ currently resides at a
star formation minimum. Using orbital modelling, we derive the
three-dimensional geometry of the CMZ and show how the orbital dynamics and the
star formation potential of the gas are closely coupled. We discuss how this
coupling reveals the physics of star formation and feedback under the
conditions seen in high-redshift galaxies, and promotes the formation of the
densest stellar clusters in the Galaxy.


title: On the origin of horseshoes in transitional discs

abstract:
  We investigate whether the rings, lopsided features and horseshoes observed
at millimetre wavelengths in transitional discs can be explained by the
dynamics of gas and dust at the edge of the cavity in circumbinary discs. We
use 3D dusty smoothed particle hydrodynamics calculations to show that binaries
with mass ratio $q \gtrsim 0.04$ drive eccentricity in the central cavity,
naturally leading to a crescent-like feature in the gas density, which is
accentuated in the mm dust grain population with intensity contrasts in
mm-continuum emission of 10 or higher. We perform mock observations to
demonstrate that these features closely match those observed by ALMA,
suggesting that the origin of rings, dust horseshoes and other non-axisymmetric
structures in transition discs can be explained by the presence of massive
companions.


title: Simulations of Magnetic Fields in Tidally-Disrupted Stars

abstract:
  We perform the first magnetohydrodynamical simulations of tidal disruptions
of stars by supermassive black holes. We consider stars with both tangled and
ordered magnetic fields, for both grazing and deeply disruptive encounters.
When the star survives disruption, we find its magnetic field amplifies by a
factor of up to twenty, but see no evidence for the a self-sustaining dynamo
that would yield arbitrary field growth. For stars that do not survive, and
within the tidal debris streams produced in partial disruptions, we find that
the component of the magnetic field parallel to the direction of stretching
along the debris stream only decreases slightly with time, eventually resulting
in a stream where the magnetic pressure is in equipartition with the gas. Our
results suggest that the returning gas in most (if not all) stellar tidal
disruptions is already highly magnetized by the time it returns to the black
hole.


title: Libration of strongly-oriented polar molecules inside a superfluid

abstract:
  We study a polar molecule immersed into a superfluid environment, such as a
helium nanodroplet or a Bose-Einstein condensate, in the presence of an intense
electrostatic field. We show that coupling of the molecular pendular motion,
induced by the field, to the fluctuating bath leads to formation of pendulons
-- spherical harmonic librators dressed by a field of many-particle
excitations. We study the behavior of the pendulon in a broad range of
molecule-bath and molecule-field interaction strengths, and reveal that its
spectrum features series of instabilities which are absent in the field-free
case of the angulon quasiparticle. Furthermore, we show that an external field
allows to finetune the positions of these instabilities in the molecular
rotational spectrum. This opens the door to detailed experimental studies of
redistribution of orbital angular momentum in many-particle systems.

categories: physics.atom-ph cond-mat.mes-hall cond-mat.quant-gas physics.atm-clus physics.chem-ph


title: Strong cycles and intersection products on good moduli spaces

abstract:
  We introduce conjectures relating the Chow ring of a smooth Artin stack
$\mathcal{X}$ to the Chow groups of its possibly singular good moduli space
$X$. In particular, we conjecture the existence of an intersection product on a
subgroup of the full Chow group $A^*(X)$ coming from strong cycles on
$\mathcal{X}$.


title:
Van't Hoff's law for active suspensions: the role of the solvent
  chemical potential

abstract:
  We extend Van't Hoff's law for the osmotic pressure to a suspension of active
Brownian particles. The propelled particles exert a net reaction force on the
solvent, and thereby either drive a measurable solvent flow from the connecting
solvent reservoir through the semipermeable membrane, or increase the osmotic
pressure and cause the suspension to rise to heights as large as micrometers
for experimentally realized microswimmers described in the literature. The
increase in osmotic pressure is caused by the background solvent being, in
contrast to passive suspensions, no longer at the chemical potential of the
solvent reservoir. The difference in solvent chemical potentials depends on the
colloid-membrane interaction potential, which implies that the osmotic pressure
is a state function of a state that itself is influenced by the membrane
potential.


title: Instanton corrections to twist-two operators

abstract:
  We present the calculation of the leading instanton contribution to the
scaling dimensions of twist-two operators with arbitrary spin and to their
structure constants in the OPE of two half-BPS operators in $\mathcal N=4$ SYM.
For spin-two operators we verify that, in agreement with $\mathcal N=4$
superconformal Ward identities, the obtained expressions coincide with those
for the Konishi operator. For operators with high spin we find that the leading
instanton correction vanishes. This arises as the result of a rather involved
calculation and requires a better understanding.


title: Higher Rank ABJM Wilson Loops from Matrix Models

abstract:
  We compute the vacuum expectation values of $1/6$ supersymmetric Wilson loops
in higher dimensional representations of the gauge group in ABJM theory. We
present results for the $m$-symmetric and $m$-antisymmetric representations by
exploiting standard matrix model techniques. At leading order, in the saddle
point approximation, our expressions reproduce holographic results from both D6
and D2 branes corresponding to the antisymmetric and symmetric representations,
respectively. We also compute 1/N corrections to the leading saddle point
results.


title: A Mode-Sum Prescription for Vacuum Polarization in Odd Dimensions

abstract:
  We present a new mode-sum regularization prescription for computing the
vacuum polarization of a scalar field in static spherically-symmetric black
hole spacetimes in odd dimensions. This is the first general and systematic
approach to regularized vacuum polarization in higher dimensions. Remarkably,
the regularization parameters can be computed in closed form in arbitrary
dimensions and for arbitrary metric function $f(r)$. In fact, we show that in
spite of the increasing severity and number of the divergences to be
regularized, the method presented is mostly agnostic to the number of
dimensions. Finally, as an explicit example of our method, we show plots for
vacuum polarization in the Schwarzschild-Tangherlini spacetime for odd
$d=5,...,11$.


title:
Galaxy bias from galaxy-galaxy lensing in the DES Science Verification
  Data

abstract:
  We present a measurement of galaxy-galaxy lensing around a magnitude-limited
($i_{AB} < 22.5$) sample of galaxies from the Dark Energy Survey Science
Verification (DES-SV) data. We split these lenses into three
photometric-redshift bins from 0.2 to 0.8, and determine the product of the
galaxy bias $b$ and cross-correlation coefficient between the galaxy and dark
matter overdensity fields $r$ in each bin, using scales above 4 Mpc/$h$
comoving, where we find the linear bias model to be valid given our current
uncertainties. We compare our galaxy bias results from galaxy-galaxy lensing
with those obtained from galaxy clustering (Crocce et al. 2016) and CMB lensing
(Giannantonio et al. 2016) for the same sample of galaxies, and find our
measurements to be in good agreement with those in Crocce et al. (2016), while,
in the lowest redshift bin ($z\sim0.3$), they show some tension with the
findings in Giannantonio et al. (2016). We measure $b\cdot r$ to be $0.87\pm
0.11$, $1.12 \pm 0.16$ and $1.24\pm 0.23$, respectively for the three redshift
bins of width $\Delta z = 0.2$ in the range $0.2<z <0.8$, defined with the
photometric-redshift algorithm BPZ. Using a different code to split the lens
sample, TPZ, leads to changes in the measured biases at the 10-20\% level, but
it does not alter the main conclusion of this work: when comparing with Crocce
et al. (2016) we do not find strong evidence for a cross-correlation parameter
significantly below one in this galaxy sample, except possibly at the lowest
redshift bin ($z\sim 0.3$), where we find $r = 0.71 \pm 0.11$ when using TPZ,
and $0.83 \pm 0.12$ with BPZ.


title: Anisotropies of Gravitational Wave Backgrounds: A Line Of Sight Approach

abstract:
  In the weak field regime, gravitational waves can be considered as being made
up of collisionless, relativistic tensor modes that travel along null geodesics
of the perturbed background metric. We work in this geometric optics picture to
calculate the anisotropies in gravitational wave backgrounds resulting from
astrophysical and cosmological sources. Our formalism yields expressions for
the angular power spectrum of the anisotropies. We show how the anisotropies
are sourced by intrinsic, Doppler, Sachs-Wolfe, and Integrated Sachs-Wolfe
terms in analogy with Cosmic Microwave Background photons.


title:
Clues to the nature of ultra diffuse galaxies from estimated galaxy
  velocity dispersions

abstract:
  We describe how to estimate the velocity dispersions of ultra diffuse
galaxies, UDGs, using a previously defined galaxy scaling relationship. The
method is accurate for the two UDGs with spectroscopically measured
dispersions, as well as for ultra compact galaxies, ultra faint galaxies, and
stellar systems with little or no dark matter. This universality means that the
relationship can be applied without further knowledge or prejudice regarding
the structure of a galaxy. We then estimate the velocity dispersions of UDGs
drawn from two published samples and examine the distribution of total masses.
We find, in agreement with the previous studies of two individual UDGs, that
these systems are dark matter dominated systems, and that they span a range of
at least $10^{10} < M_{200}/M_\odot < 10^{12} $. These galaxies are not, as an
entire class, either all dwarfs or all failed $L_*$ galaxies. Estimates of the
velocity dispersions can also help identify interesting subsets of UDGs, such
as those that are likely to have the largest mass-to-light ratios, for
subsequent spectroscopic study.


title: An efficient quantum algorithm for spectral estimation

abstract:
  We develop an efficient quantum implementation of an important signal
processing algorithm for line spectral estimation: the matrix pencil method,
which determines the frequencies and damping factors of signals consisting of
finite sums of exponentially damped sinusoids. Our algorithm provides a quantum
speedup in a natural regime where the sampling rate is much higher than the
number of sinusoid components. Along the way, we develop techniques that are
expected to be useful for other quantum algorithms as well - consecutive phase
estimations to efficiently make products of asymmetric low rank matrices
classically accessible and an alternative method to efficiently exponentiate
non-Hermitian matrices. Our algorithm features an efficient quantum-classical
division of labor: The time-critical steps are implemented in quantum
superposition, while an interjacent step, requiring only exponentially few
parameters, can operate classically. We show that frequencies and damping
factors can be obtained in time logarithmic in the number of sampling points,
exponentially faster than known classical algorithms.


title: Energy Dependence of SEP Electron and Proton Onset Times

abstract:
  We study the large solar energetic particle (SEP) events that were detected
by GOES in the $>$ 10 MeV energy channel during December 2006 to March 2014. We
derive and compare solar particle release (SPR) times for the 0.25--10.4 MeV
electrons and 10--100 MeV protons for the 28 SEP events. In the study, the
electron SPR times are derived with the time-shifting analysis (TSA) and the
proton SPR times are derived using both the TSA and the velocity dispersion
analysis (VDA). Electron anisotropies are computed to evaluate the amount of
scattering for the events under study. Our main results include:
1)near-relativistic electrons and high-energy protons are released at the same
time within 8 min for most (16 of 23) SEP events. 2)There exists a good
correlation between electron and proton acceleration, peak intensity and
intensity time profiles. 3) The TSA SPR times for 90.5 MeV and 57.4 MeV protons
have maximum errors of 6 min and 10 min compared to the proton VDA release
times, respectively, while the maximum error for 15.4 MeV protons can reach to
32 min. 4) For 7 low-intensity events of the 23, large delays occurred between
6.5 MeV electrons and 90.5 MeV protons relative to 0.5 MeV electrons. Whether
these delays are due to times needed for the evolving shock to be strengthened
or due to particle transport effects remains unresolved.


title: The Clifford group fails gracefully to be a unitary 4-design

abstract:
  A unitary t-design is a set of unitaries that is "evenly distributed" in the
sense that the average of any t-th order polynomial over the design equals the
average over the entire unitary group. In various fields -- e.g. quantum
information theory -- one frequently encounters constructions that rely on
matrices drawn uniformly at random from the unitary group. Often, it suffices
to sample these matrices from a unitary t-design, for sufficiently high t. This
results in more explicit, derandomized constructions. The most prominent
unitary t-design considered in quantum information is the multi-qubit Clifford
group. It is known to be a unitary 3-design, but, unfortunately, not a
4-design. Here, we give a simple, explicit characterization of the way in which
the Clifford group fails to constitute a 4-design. Our results show that for
various applications in quantum information theory and in the theory of convex
signal recovery, Clifford orbits perform almost as well as those of true
4-designs. Technically, it turns out that in a precise sense, the 4th tensor
power of the Clifford group affords only one more invariant subspace than the
4th tensor power of the unitary group. That additional subspace is a stabilizer
code -- a structure extensively studied in the field of quantum error
correction codes. The action of the Clifford group on this stabilizer code can
be decomposed explicitly into previously known irreps of the discrete
symplectic group. We give various constructions of exact complex projective
4-designs or approximate 4-designs of arbitrarily high precision from Clifford
orbits. Building on results from coding theory, we give strong evidence
suggesting that these orbits actually constitute complex projective 5-designs.


title:
Investigation of Dephasing In an Open Quantum System under Chaotic
  Influence via a Fractional Kohn-Sham Scheme

abstract:
  In this work, the dynamics of dephasing (without relaxation) in the presence
of a chaotic oscillator is theoretically investigated. The time-dependent
density functional theory (TDDFT) framework was employed in tandem with the
Lindblad master equation approach for modeling the dissipation dynamics. By
employing the Kohn-Sham (K-S) scheme under certain approximations, the exact
model system for the potentials was acquired. In addition, a space-fractional
K-S scheme is developed (using the modified Riemann-Liouville operator) for
modeling the dephasing phenomenon. Extensive analyses and comparative studies
were then done on the results obtained using the space-fractional K-S system
and the conventional K-S system.


title:
Reversed radial distribution trend of subpopulations in the globular
  clusters NGC 362 and NGC 6723

abstract:
  Most globular clusters (GCs) are now known to host multiple stellar
populations with different light element abundances. Here we use narrow-band
photometry and low-resolution spectroscopy for NGC 362 and NGC 6723 to
investigate their chemical properties and radial distributions of
subpopulations. We confirm that NGC 362 and NGC 6723 are among the GCs with
multiple populations showing bimodal CN distribution and CN-CH anti-correlation
without a significant spread in calcium abundance. These two GCs show more
centrally concentrated CN-weak earlier generation stars compared to the later
generation CN-strong stars. These trends are reversed with respect to those
found in previous studies for many other GCs. Our findings, therefore, seem
contradictory to the current scenario for the formation of multiple stellar
populations, but mass segregation acting on the two subpopulations might be a
possible solution to explain this reversed radial trend.


title:
OGLE Collection of Star Clusters. New Objects in the Outskirts of the
  Large Magellanic Cloud

abstract:
  The Magellanic System (MS), consisting of the Large Magellanic Cloud (LMC),
the Small Magellanic Cloud (SMC) and the Magellanic Bridge (MBR), contains
diverse sample of star clusters. Their spatial distribution, ages and chemical
abundances may provide important information about the history of formation of
the whole System. We use deep photometric maps derived from the images
collected during the fourth phase of The Optical Gravitational Lensing
Experiment (OGLE-IV) to construct the most complete catalog of star clusters in
the Large Magellanic Cloud using the homogeneous photometric data. In this
paper we present the collection of star clusters found in the area of about 225
square degrees in the outer regions of the LMC. Our sample contains 679
visually identified star cluster candidates, 226 of which were not listed in
any of the previously published catalogs. The new clusters are mainly young
small open clusters or clusters similar to associations.


title: Wall-Crossing in Genus Zero K-theoretic Landau-Ginzburg Theory

abstract:
  For a Fermat quasi-homogeneous polynomial $W$, we study a family of
K-theoretic quantum invariants parametrized by a positive rational number
$\epsilon$. We prove a wall-crossing formula by showing the generating
functions lie on the Lagrangian cone of the permutation-equivariant K-theoretic
FJRW theory of $W$.


title: Extragradient Method in Optimization: Convergence and Complexity

abstract:
  We consider the extragradient method to minimize the sum of two functions,
the first one being smooth and the second being convex. Under the
Kurdyka-Lojasiewicz assumption, we prove that the sequence produced by the
extragradient method converges to a critical point of the problem and has
finite length. The analysis is extended to the case when both functions are
convex. We provide, in this case, a sublinear convergence rate, as for
gradient-based methods. Furthermore, we show that the recent small-prox
complexity result can be applied to this method. Considering the extragradient
method is an occasion to describe an exact line search scheme for proximal
decomposition methods. We provide details for the implementation of this scheme
for the one norm regularized least squares problem and demonstrate numerical
results which suggest that combining nonaccelerated methods with exact line
search can be a competitive choice.


title:
Quantum Statistical Mechanics as an Exact Classical Expansion with
  Results for Lennard-Jones Helium

abstract:
  The quantum states representing classical phase space are given, and these
are used to formulate quantum statistical mechanics as a formally exact double
perturbation expansion about classical statistical mechanics. One series of
quantum contributions arises from the non-commutativity of the position and
momentum operators. Although the formulation of the quantum states differs, the
present results for separate averages of position operators and of momentum
operators agree with Wigner (1932) and Kirkwood (1933). The second series
arises from wave function symmetrization, and is given in terms of $l$-particle
permutation loops in an infinite order re-summation. The series gives
analytically the known exact result for the quantum ideal gas to all orders.
The leading correction corrects a correction given by Kirkwood.
  The first four quantum corrections to the grand potential are calculated for
a Lennard-Jones fluid using the hypernetted chain closure. For helium on liquid
branch isotherms, the corrections range from several times to 1\% of the total
classical pressure, with the effects of non-commutativity being significantly
larger in magnitude than those of wave function symmetrization. All corrections
are found to be negligible for argon at the densities and temperatures studied.
The calculations are computationally trivial as the method avoids having to
compute eigenfunctions, eigenvalues, and numerical symmetrization.


title:
Quantifying and controlling biases in dark matter halo concentration
  estimates

abstract:
  We use bootstrapping to estimate the bias of concentration estimates on
N-body dark matter halos as a function of particle number. We find that
algorithms based on the maximum radial velocity and radial particle binning
tend to overestimate the concentration by 15%-20% for halos sampled with 200
particles and by 7% - 10% for halos sampled with 500 particles. To control this
bias at low particle numbers we propose a new algorithm that estimates halo
concentrations based on the integrated mass profile. The method uses the full
particle information without any binning, making it reliable in cases when low
numerical resolution becomes a limitation for other methods. This method
reduces the bias to less than 3% for halos sampled with 200-500 particles. The
velocity and density methods have to use halos with at least 4000 particles in
order to keep the biases down to the same low level. We also show that the
mass-concentration relationship could be shallower than expected once the
biases of the different concentration measurements are taken into account.
These results show that bootstrapping and the concentration estimates based on
the integrated mass profile are valuable tools to probe the internal structure
of dark matter halos in numerical simulations.


title:
Coupled variational formulations of linear elasticity and the DPG
  methodology

abstract:
  This article presents a general approach akin to domain-decomposition methods
to solve a single linear PDE, but where each subdomain of a partitioned domain
is associated to a distinct variational formulation coming from a mutually
well-posed family of broken variational formulations of the original PDE. It
can be exploited to solve challenging problems in a variety of physical
scenarios where stability or a particular mode of convergence is desired in a
part of the domain. The linear elasticity equations are solved in this work,
but the approach can be applied to other equations as well. The broken
variational formulations, which are essentially extensions of more standard
formulations, are characterized by the presence of mesh-dependent broken test
spaces and interface trial variables at the boundaries of the elements of the
mesh. This allows necessary information to be naturally transmitted between
adjacent subdomains, resulting in coupled variational formulations which are
then proved to be globally well-posed. They are solved numerically using the
DPG methodology, which is especially crafted to produce stable discretizations
of broken formulations. Finally, expected convergence rates are verified in two
different and illustrative examples.


title: Effect of Negative Pressure on the Prototypical Itinerant Magnet MnSi

abstract:
  The evolution of the magnetic and charge transport properties of itinerant
magnetic metal MnSi with the substitution of Al and Ga on the Si site is
investigated. We observe an increase in unit cell volume indicating that both
Al and Ga substitutions create negative chemical pressure. There are
substantial increases in the Curie temperature and the ordered moment
demonstrating that the substitutions give the magnetism a more local character.
The substitutions also increase the range of temperature and field where the
skyrmion phase is stable due to a change in the character of the magnetism. In
contrast to the behavior of pure MnSi and expectations for the intrinsic
anomalous Hall effect, we find a significant temperature dependence to the
magnitude and sign of anomalous Hall conductivity constant in Al or Ga
substituted samples. This temperature dependence likely reflects changes in the
spin-orbit coupling strength with temperature, which may have significant
consequences on the helical and skyrmion states. Overall, we observe a
continuous evolution of magnetic and charge transport properties through
positive to negative pressure


title:
Availability-Aware Cell Association for Hybrid Power Supply Networks
  with Adaptive Bias

abstract:
  New challenges have emerged from the integration of renewable energy sources
within the conventional electrical grid which powers base stations (BS).
Energy-aware traffic offloading brings a promising solution to maintain the
user performance while reducing the carbon footprint. Focusing on downlink
cellular networks consisting of on-grid, off-grid and hybrid BSs, we propose a
novel power-aware biased cell association where each user independently
partitions BSs into two sets and applies different association biases for each,
depending on the type of power, renewable or not, that can be requested for
service. The gain provided by such strategy regarding the probability of power
outage and the average grid power consumption is investigated. To capture their
dual nature, the bias applied for association with a hybrid BS is not constant
among users nor over time, and is dynamically tailored to the fluctuations of
the BS battery level, the user power requirement and the estimated power
consumed to serve other users potentially associated with the same BS. Such
approach allows to efficiently share the available energy among BSs and turns
high heterogeneity in the BS powering into advantage.


title:
The asymptotic behavior of limit-periodic functions on primes and an
  application to k-free numbers

abstract:
  We use the circle method to evaluate the behavior of limit-periodic functions
on primes. For those limit-periodic functions that satisfy a kind of
Barban-Davenport-Halberstam condition and whose singular series converge fast
enough, we can evaluate their average value on primes. As an application, this
result is used to show how tuples of different k-free numbers behave when
linear shifts are applied.


title: Families of elliptic curves in $\mathbb{P}^3$ and Bridgeland Stability

abstract:
  We study wall crossings in Bridgeland stability for the Hilbert scheme of
elliptic quartic curves in three dimensional projective space. We provide a
geometric description of each of the moduli spaces we encounter, including when
the second component of this Hilbert scheme appears. Along the way, we prove
that the principal component of this Hilbert scheme is a double blow up with
smooth centers of a Grassmannian, exhibiting a completely different proof of
this known result by Avritzer and Vainsencher. This description allows us to
compute the cone of effective divisors of this component.


title:
The Abundance of Atmospheric CO2 in Ocean Exoplanets: A Novel CO2
  Deposition Mechanism

abstract:
  We consider super-Earth sized planets which have a water mass fraction that
is large enough to form an external mantle composed of high pressure water ice
polymorphs and that lack a substantial H/He atmosphere. We consider such
planets in their habitable zone so that their outermost condensed mantle is a
global deep liquid ocean. For these ocean planets we investigate potential
internal reservoirs of CO2; the amount of CO2 dissolved in the ocean for the
various saturation conditions encountered, and the ocean-atmosphere exchange
flux of CO2. We find that in steady state the abundance of CO2 in the
atmosphere has two possible states. When the wind-driven circulation is the
dominant CO2 exchange mechanism, an atmosphere of tens of bars of CO2 results,
where the exact value depends on the subtropical ocean surface temperature and
the deep ocean temperature. When sea-ice formation, acting on these planets as
a CO2 deposition mechanism, is the dominant exchange mechanism, an atmosphere
of a few bars of CO2 is established. The exact value depends on the subpolar
surface temperature. Our results suggest the possibility of a negative feedback
mechanism, unique to water planets, where a reduction in the subpolar
temperature drives more CO2 into the atmosphere to increase the greenhouse
effect.


title: Extremal functions for Morrey's inequality in convex domains

abstract:
  For a bounded domain $\Omega\subset \mathbb{R}^n$ and $p>n$, Morrey's
inequality implies that there is $c>0$ such that $$ c\|u\|^p_{\infty}\le
\int_\Omega|Du|^pdx $$ for each $u$ belonging to the Sobolev space
$W^{1,p}_0(\Omega)$. We show that the ratio of any two extremal functions is
constant provided that $\Omega$ is convex. We also explain why this property
fails to hold in general and verify that convexity is not a necessary condition
for a domain to have this property. As a by product, we obtain the uniqueness
of an optimization problem involving the Green's function for the
$p$-Laplacian.


title: The Effect of DNS on Tor's Anonymity

abstract:
  Previous attacks that link the sender and receiver of traffic in the Tor
network ("correlation attacks") have generally relied on analyzing traffic from
TCP connections. The TCP connections of a typical client application, however,
are often accompanied by DNS requests and responses. This additional traffic
presents more opportunities for correlation attacks. This paper quantifies how
DNS traffic can make Tor users more vulnerable to correlation attacks. We
investigate how incorporating DNS traffic can make existing correlation attacks
more powerful and how DNS lookups can leak information to third parties about
anonymous communication. We (i) develop a method to identify the DNS resolvers
of Tor exit relays; (ii) develop a new set of correlation attacks (DefecTor
attacks) that incorporate DNS traffic to improve precision; (iii) analyze the
Internet-scale effects of these new attacks on Tor users; and (iv) develop
improved methods to evaluate correlation attacks. First, we find that there
exist adversaries who can mount DefecTor attacks: for example, Google's DNS
resolver observes almost 40% of all DNS requests exiting the Tor network. We
also find that DNS requests often traverse ASes that the corresponding TCP
connections do not transit, enabling additional ASes to gain information about
Tor users' traffic. We then show that an adversary who can mount a DefecTor
attack can often determine the website that a Tor user is visiting with perfect
precision, particularly for less popular websites where the set of DNS names
associated with that website may be unique to the site. We also use the Tor
Path Simulator (TorPS) in combination with traceroute data from vantage points
co-located with Tor exit relays to estimate the power of AS-level adversaries
who might mount DefecTor attacks in practice.


title: Representations of the multi-qubit Clifford group

abstract:
  The Clifford group is a fundamental structure in quantum information with a
wide variety of applications. We discuss the tensor representations of the
$q$-qubit Clifford group, which is defined as the normalizer of the $q$-qubit
Pauli group in $U(2^q)$. In particular, we characterize all irreducible
subrepresentations of the two-copy representation $\varphi^{\otimes2}$ of the
Clifford group on the matrix space $\mathbb{C}^{d\times d}\otimes
\mathbb{C}^{d\times d}$ with $d=2^q$. In an upcoming companion paper we applied
this result to cut down the number of samples necessary to perform randomised
benchmarking, a method for characterising quantum systems.


title:
Ricci curvature non-minimal derivative coupling cosmology with field
  re-scaling

abstract:
  In this letter, cosmology of a simple NMDC gravity with $\xi R
\phi_{,\mu}\phi^{,\mu}$ term and a free kinetic term is considered in flat
geometry and in presence of dust matter. A logarithm field transformation
$\phi' = \mu \ln \phi$ is proposed phenomenologically. Assuming slow-roll
approximation, equation of motion, scalar field solution and potential are
derived as function of kinematic variables. The field solution and potential
are found straightforwardly for power-law, de-Sitter and super-acceleration
expansions. Slow-roll parameters and slow-roll condition are found to depend on
more than one variable. At large field the re-scaling effect can enhance the
acceleration. For slow-rolling field, the negative coupling $\xi$ could enhance
the effect of acceleration.


title: Bead-rod-spring models in random flows

abstract:
  Bead-rod-spring models are the foundation of the kinetic theory of polymer
solutions. We derive the diffusion equation for the probability density
function of the configuration of a general bead-rod-spring model in
short-correlated Gaussian random flows. Under isotropic conditions, we solve
this equation analytically for the elastic rhombus model introduced by Curtiss,
Bird, and Hassager [Adv. Chem. Phys. 35 (1976), pp. 31-117].


title:
Modeling the thermo-mechanical behavior of a woven ceramic matrix
  composite at high temperatures

abstract:
  This paper aimed at extending a model developed by Ladeveze to capture
thermal expansion and coupled thermo-mechanical phenomena, as such as those
encountered at elevated and extreme temperatures. In the new model a linear
thermal expansion coefficient is added to equation of state to account for the
thermal to mechanical coupling effects. The mechanical to thermal effects are
introduced by assuming an internal heat generation due to residual strain
effects. The constitutive relations of the coupled thermo-mechanical behaviors
of ceramic matrix composite material model were incorporated into Abaqus finite
element code as user defined material software. An extension of the methodology
presented by Letombes to calibrate the ceramic matrix composite damage model
parameters based on a woven silicon-carbide silicon-carbide material developed
by Safran Group. Feasibility tests (tension-compression, tension-tension
cyclic, simple tension tests) based on a dog bone and open hole specimen tests
demonstrated a good capturing of nonlinear as well as coupled
thermos-mechanical behaviors in the silicon-carbide silicon-carbide material.


title:
FPGA Implementation of High Speed Reconfigurable Filter Bank for
  Multi-standard Wireless Communication Receivers

abstract:
  In next generation wireless communication system, wireless transceivers
should be able to handle wideband input signals compromising of multiple
communication standards.Such multi-standard wireless communication receivers
(MWCRs) need filter bank to extract the desired signal of interest from
wideband input spectrum and bring it to the baseband for further signal
processing tasks such as spectrum sensing, modulation
classification,demodulation etc.In MWCRs,rather any wireless receivers,
modulated filter banks, such as Discrete Fourier Transform Filter Banks
(DFTFB), are preferred due to their advantages such as lower area, delay and
power requirements. To support multi-standard operation, reconfigurable DFTFB
(RDFTFB) was proposed by integrating DFTFB with the coefficient decimation
method. In this paper, an efficient high speed implementation of RDFTFB on
Virtex-7 field programmable gate arrays (FPGA) has been proposed.The proposed
approach minimizes the critical path delay between clocked registers thereby
leading to significant improvement in the maximum operating frequency of the
RDFTFB. Numerically, the proposed implementation leads to 89.7% improvement in
the maximum frequency at which RDFTFB can be clocked.Furthermore,proposed
implementation leads to 18.5% reduction in the dynamic power consumption.


title: Asymptotic behavior of the curves in the Fu{\v{c}}{\'{\i}}k spectrum

abstract:
  In this work we study the asymptotic behavior of the curves of the
Fu{\v{c}}{\'{\i}}k spectrum for weighted second order linear ordinary
differential equations. We prove a Weyl type asymptotic behavior of the
hyperbolic type curves in the spectrum in terms of some integrals of the
weights. We present an algorithm which computes the intersection of the
Fu{\v{c}}{\'{\i}}k spectrum with rays through the origin, and we compare their
values with the asymptotic ones.


title: Online Segment to Segment Neural Transduction

abstract:
  We introduce an online neural sequence to sequence model that learns to
alternate between encoding and decoding segments of the input as it is read. By
independently tracking the encoding and decoding representations our algorithm
permits exact polynomial marginalization of the latent segmentation during
training, and during decoding beam search is employed to find the best
alignment path together with the predicted output sequence. Our model tackles
the bottleneck of vanilla encoder-decoders that have to read and memorize the
entire input sequence in their fixed-length hidden states before producing any
output. It is different from previous attentive models in that, instead of
treating the attention weights as output of a deterministic function, our model
assigns attention weights to a sequential latent variable which can be
marginalized out and permits online generation. Experiments on abstractive
sentence summarization and morphological inflection show significant
performance gains over the baseline encoder-decoders.


title: The Newtonian mechanics of a Vibrot

abstract:
  A mechanical model was developed to describe the behaviour of a device able
to transform vibrations into rotations, named Vibrot. The theoretical model,
developed in the newtonian formulation of mechanics, was able to reproduce
qualitatively all the experimental results existing in the literature, and
quantitatively some of them.


title:
Far-infrared quantum cascade lasers operating in AlAs phonon
  Reststrahlen band

abstract:
  We report on the operation of a double metal waveguide far-infrared quantum
cascade laser emitting at 28 $\mu$m, corresponding to the AlAs-like phonon
Reststrahlen band. To avoid absorption by AlAs-like optical phonons, the
Al-free group-V alloy GaAs$_{0.51}$Sb$_{0.49}$ is used as a barrier layer in
the bound-to-continuum based active region. Lasing occurs at a wavelength of
28.3 $\mu$m, which is the longest wavelength among the quantum cascade lasers
operating from mid-infrared to far-infrared. The threshold current density at
50 K is 5.5 kA/cm$^{2}$ and maximum operation temperature is 175 K. We also
discuss the feasibility that operation wavelength cover the whole spectral
range bridging between mid-infrared and terahertz by choosing suited group
III-V materials.


title:
Homogeneous solutions of stationary Navier-Stokes equations with
  isolated singularities on the unit sphere. I. One singularity

abstract:
  We classify all $(-1)-$homogeneous axisymmetric no swirl solutions of
incompressible stationary Navier-Stokes equations in three dimension which are
smooth on the unit sphere minus the south pole, parameterize them as a two
dimensional surface with boundary, and analyze their pressure profiles near the
north pole. Then we prove that there is a curve of $(-1)-$homogeneous
axisymmetric solutions with nonzero swirl, having the same smoothness property,
emanating from every point of the interior and one part of the boundary of the
solution surface. Moreover we prove that there is no such curve of solutions
for any point on the other part of the boundary. We also establish asymptotic
expansions for every (-1)-homogeneous axisymmetric solutions in a neighborhood
of the singular point on the unit sphere.


title: Generalized Line Spectral Estimation via Convex Optimization

abstract:
  Line spectral estimation is the problem of recovering the frequencies and
amplitudes of a mixture of a few sinusoids from equispaced samples. However, in
a variety of signal processing problems arising in imaging, radar, and
localization we do not have access directly to such equispaced samples. Rather
we only observe a severely undersampled version of these observations through
linear measurements. This paper is about such generalized line spectral
estimation problems. We reformulate these problems as sparse signal recovery
problems over a continuously indexed dictionary which can be solved via a
convex program. We prove that the frequencies and amplitudes of the components
of the mixture can be recovered perfectly from a near-minimal number of
observations via this convex program. This result holds provided the
frequencies are sufficiently separated, and the linear measurements obey
natural conditions that are satisfied in a variety of applications.


title:
Least squares estimator of fractional Ornstein Uhlenbeck processes with
  periodic mean

abstract:
  We first study the drift parameter estimation of the fractional
Ornstein-Uhlenbeck process (fOU) with periodic mean for every
$\frac{1}{2}<H<1$. More precisely, we extend the consistency proved in
\cite{DFW} for $\frac{1}{2}<H<\frac{3}{4}$ to the strong consistency for any
$\frac{1}{2}<H<1$ on the one hand, and on the other, we also discuss the
asymptotic normality given in \cite{DFW}. In the second main part of the paper,
we study the strong consistency and the asymptotic normality of the fOU of the
second kind with periodic mean for any $\frac{1}{2}<H<1$.


title:
On Green functions of second-order elliptic operators on Riemannian
  manifolds: The critical case

abstract:
  Let P be a second-order, linear, elliptic operator with real coefficients
which is defined on a noncompact and connected Riemannian manifold M. It is
well known that the equation Pu = 0 in M admits a positive supersolution which
is not a solution if and only if P admits a unique positive minimal Green
function on M, and in this case, P is said to be subcritical in M. If P does
not admit a positive Green function but admits a global positive solution, then
such a solution is called a ground state of P in M, and P is said to be
critical in M. We prove for a critical operator P in M, the existence of a
Green function which is dominated above by the ground state of P away from the
singularity. Moreover, in a certain class of Green functions, such a Green
function is unique, up to an addition of a product of the ground states of P
and P^{\star}. Under some further assumptions, we describe the behaviour at
infinity of such a Green function. This result extends and sharpens the
celebrated result of P. Li and L.-F. Tam concerning the existence of a
symmetric Green function for the Laplace-Beltrami operator on a smooth and
complete Riemannian manifold M.


title:
Robust Time-Series Retrieval Using Probabilistic Adaptive Segmental
  Alignment

abstract:
  Traditional pairwise sequence alignment is based on matching individual
samples from two sequences, under time monotonicity constraints. However, in
many application settings matching subsequences (segments) instead of
individual samples may bring in additional robustness to noise or local
non-causal perturbations. This paper presents an approach to segmental sequence
alignment that jointly segments and aligns two sequences, generalizing the
traditional per-sample alignment. To accomplish this task, we introduce a
distance metric between segments based on average pairwise distances and then
present a modified pair-HMM (PHMM) that incorporates the proposed distance
metric to solve the joint segmentation and alignment task. We also propose a
relaxation to our model that improves the computational efficiency of the
generic segmental PHMM. Our results demonstrate that this new measure of
sequence similarity can lead to improved classification performance, while
being resilient to noise, on a variety of sequence retrieval problems, from EEG
to motion sequence classification.


title:
Sub-molecular modulation of a 4f driven Kondo resonance by
  surface-induced asymmetry

abstract:
  Coupling between a magnetic impurity and an external bath can give rise to
many-body quantum phenomena, including Kondo and Hund's impurity states in
metals, and Yu-Shiba-Rusinov states in superconductors. While advances have
been made in probing the magnetic properties of d-shell impurities on surfaces,
the confinement of f orbitals makes them difficult to access directly. Here we
show that a 4f driven Kondo resonance can be modulated spatially by asymmetric
coupling between a metallic surface and a molecule containing a 4f-like moment.
Strong hybridisation of dysprosium double-decker phthalocyanine with Cu(001)
induces Kondo screening of the central magnetic moment. Misalignment between
the symmetry axes of the molecule and the surface induces asymmetry in the
molecule's electronic structure, spatially mediating electronic access to the
magnetic moment through the Kondo resonance. This work demonstrates the
important role that molecular ligands play in mediating electronic and magnetic
coupling and in accessing many-body quantum states.


title: Variational Inference with Hamiltonian Monte Carlo

abstract:
  Variational inference lies at the core of many state-of-the-art algorithms.
To improve the approximation of the posterior beyond parametric families, it
was proposed to include MCMC steps into the variational lower bound. In this
work we explore this idea using steps of the Hamiltonian Monte Carlo (HMC)
algorithm, an efficient MCMC method. In particular, we incorporate the
acceptance step of the HMC algorithm, guaranteeing asymptotic convergence to
the true posterior. Additionally, we introduce some extensions to the HMC
algorithm geared towards faster convergence. The theoretical advantages of
these modifications are reflected by performance improvements in our
experimental results.


title:
Circularly invariant uniformizable probability measures for linear
  transformations

abstract:
  In this paper, we prove a threshold result on the existence of a circularly
invariant uniformizable probability measure (CIUPM) for linear transformations
with non-zero slope on the line. We show that there is a threshold constant $c$
depending only on the slope of the linear transformation such that there exists
a CIUPM if and only if its support has a diameter at least as large as $c.$
Moreover, the CIUPM is unique up to translation if the diameter of the support
equals $c.$


title:
Random-phase-approximation theory for sequence-dependent, biologically
  functional liquid-liquid phase separation of intrinsically disordered
  proteins

abstract:
  Intrinsically disordered proteins (IDPs) are typically low in
nonpolar/hydrophobic but relatively high in polar, charged, and aromatic amino
acid compositions. Some IDPs undergo liquid-liquid phase separation in the
aqueous milieu of the living cell. The resulting phase with enhanced IDP
concentration can function as a major component of membraneless organelles
that, by creating their own IDP-rich microenvironments, stimulate critical
biological functions. IDP phase behaviors are governed by their amino acid
sequences. To make progress in understanding this sequence-phase relationship,
we report further advances in a recently introduced application of
random-phase-approximation (RPA) heteropolymer theory to account for
sequence-specific electrostatics in IDP phase separation. Here we examine
computed variations in phase behavior with respect to block length and charge
density of model polyampholytes of alternating equal-length charge blocks to
gain insight into trends observed in IDP phase separation. As a real-life
example, the theory is applied to rationalize/predict binodal and spinodal
phase behaviors of the 236-residue N-terminal disordered region of RNA helicase
Ddx4 and its charge-scrambled mutant for which experimental data are available.
Fundamental differences are noted between the phase diagrams predicted by RPA
and those predicted by mean-field Flory-Huggins and
Overbeek-Voorn/Debye-H\"uckel theories. In the RPA context, a physically
plausible dependence of relative permittivity on protein concentration can
produce a cooperative effect in favor of IDP-IDP attraction and thus a
significant increased tendency to phase separate. Ramifications of these
findings for future development of IDP phase separation theory are discussed.


title: Reversible Vector Ratchets for Skyrmion Systems

abstract:
  We show that ac driven skyrmions interacting with an asymmetric substrate
provide a realization of a new class of ratchet system which we call a vector
ratchet that arises due to the effect of the Magnus term on the skyrmion
dynamics. In a vector ratchet, the dc motion induced by the ac drive can be
described as a vector that can be rotated clockwise or counterclockwise
relative to the substrate asymmetry direction. Up to a full $360^{\circ}$
rotation is possible for varied ac amplitudes or skyrmion densities. In
contrast to overdamped systems, in which ratchet motion is always parallel to
the substrate asymmetry direction, vector ratchets allow the ratchet motion to
be in any direction relative to the substrate asymmetry. It is also possible to
obtain a reversal in the direction of rotation of the vector ratchet,
permitting the creation of a reversible vector ratchet. We examine vector
ratchets for ac drives applied parallel or perpendicular to the substrate
asymmetry direction, and show that reverse ratchet motion can be produced by
collective effects. No reversals occur for an isolated skyrmion on an
asymmetric substrate. Since a vector ratchet can produce motion in any
direction, it could represent a new method for controlling skyrmion motion for
spintronic applications.


title: Distributional asymptotics mod 1 of $(\log_bn)$

abstract:
  This paper studies the distributional asymptotics of the slowly changing
sequence of logarithms $(\log_bn)$ with $b\in\mathbb{N}\setminus\{1\}.$ It is
known that $(\log_bn)$ is not uniformly distributed modulo one, and its omega
limit set is composed of a family of translated exponential distributions with
constant $\log b.$ An improved upper estimate $\left(\sqrt{\log N}/N\right)$ is
obtained for the rate of convergence with respect to (w.r.t.) the Kantorovich
metric on the circle, compared to the general results on rates of convergence
for a class of slowly changing sequences in the author's companion in-progress
work. Moreover, a sharp rate of convergence $\left(\log N/N\right)$ w.r.t. the
Kantorovich metric on the interval $[0,1]$, is derived. As a byproduct, the
rate of convergence w.r.t. the discrepancy metric (or the Kolmogorov metric)
turns out to be $\left(\log N/N\right)$ as well, which verifies that an upper
bound for this rate derived in [Y. Ohkubo and O. Strauch, Distribution of
leading digits of numbers, Unif. Distrib. Theory, $\textbf{11}$ (2016), no.1,
23--45.] is sharp.


title: Detecting Aortic Valve Opening and Closing from Distal Body Vibrations

abstract:
  Objective: Proximal and whole-body vibrations are well studied in
seismocardiography and ballistocardiography, yet distal vibrations are still
poorly understood. In this paper we develop two methods to measure aortic valve
opening (AVO) and closing (AVC) from distal vibrations. Methods: AVO and AVC
were detected for each heartbeat with accelerometers on the upper arm (A),
wrist (W), and knee (K) of 22 consenting adults following isometric exercise.
Exercise-induced changes were recorded with impedance cardiography, and
nine-beat ensemble averaging was applied. Our first method, FilterBCG, detects
peaks in distal vibrations after filtering with individually-tuned bandpass
filters while RidgeBCG uses ridge regression to estimate AVO and AVC without
peaks. Pseudocode is provided. Results: In agreement with recent studies, we
did not find peaks at AVO and AVC in distal vibrations, and the conventional
R-J interval method from the literature also correlated poorly with AVO (r2 =
0.22 A, 0.14 W, 0.12 K). Interestingly, distal vibrations filtered with
FilterBCG resembled seismocardiogram signals and yielded reliable peaks at AVO
(r2 = 0.95 A, 0.94 W, 0.77 K) and AVC (r2 = 0.92 A, 0.89 W, 0.68 K).
Conclusion: FilterBCG measures AVO and AVC accurately from arm, wrist, and knee
vibrations, and it outperforms R-J intervals and RidgeBCG. Significance: To our
knowledge, this study is the first to measure AVC accurately from distal
vibrations. Finally, AVO timing is needed to assess cardiovascular disease risk
with pulse wave velocity (PWV) and for cuff-less diastolic blood pressure
measurement via aortic pulse-transit time (PTT).


title:
Automatic Construction of a Recurrent Neural Network based Classifier
  for Vehicle Passage Detection

abstract:
  Recurrent Neural Networks (RNNs) are extensively used for time-series
modeling and prediction. We propose an approach for automatic construction of a
binary classifier based on Long Short-Term Memory RNNs (LSTM-RNNs) for
detection of a vehicle passage through a checkpoint. As an input to the
classifier we use multidimensional signals of various sensors that are
installed on the checkpoint. Obtained results demonstrate that the previous
approach to handcrafting a classifier, consisting of a set of deterministic
rules, can be successfully replaced by an automatic RNN training on an
appropriately labelled data.


title: Learning to Translate for Multilingual Question Answering

abstract:
  In multilingual question answering, either the question needs to be
translated into the document language, or vice versa. In addition to direction,
there are multiple methods to perform the translation, four of which we explore
in this paper: word-based, 10-best, context-based, and grammar-based. We build
a feature for each combination of translation direction and method, and train a
model that learns optimal feature weights. On a large forum dataset consisting
of posts in English, Arabic, and Chinese, our novel learn-to-translate approach
was more effective than a strong baseline (p<0.05): translating all text into
English, then training a classifier based only on English (original or
translated) text.


title:
A Robust Diarization System for Measuring Dominance in Peer-Led Team
  Learning Groups

abstract:
  Peer-Led Team Learning (PLTL) is a structured learning model where a team
leader is appointed to facilitate collaborative problem solving among students
for Science, Technology, Engineering and Mathematics (STEM) courses. This paper
presents an informed HMM-based speaker diarization system. The minimum duration
of short conversationalturns and number of participating students were fed as
side information to the HMM system. A modified form of Bayesian Information
Criterion (BIC) was used for iterative merging and re-segmentation. Finally, we
used the diarization output to compute a novel dominance score based on
unsupervised acoustic analysis.


title: Cycles of given lengths in hypergraphs

abstract:
  In this paper, we develop a method for studying cycle lengths in hypergraphs.
Our method is built on earlier ones used in [21,22,18]. However, instead of
utilizing the well-known lemma of Bondy and Simonovits [4] that most existing
methods do, we develop a new and very simple lemma in its place. One useful
feature of the new lemma is its adaptiveness for the hypergraph setting.
  Using this new method, we prove a conjecture of Verstra\"ete [37] that for
$r\ge 3$, every $r$-uniform hypergraph with average degree $\Omega(k^{r-1})$
contains Berge cycles of $k$ consecutive lengths. This is sharp up to the
constant factor. As a key step and a result of independent interest, we prove
that every $r$-uniform linear hypergraph with average degree at least $7r(k+1)$
contains Berge cycles of $k$ consecutive lengths.
  In both of these results, we have additional control on the lengths of the
cycles, which therefore also gives us bounds on the Tur\'an numbers of Berge
cycles (for even and odd cycles simultaneously). In relation to our main
results, we obtain further improvements on the Tur\'an numbers of Berge cycles
and the Zarankiewicz numbers of even cycles. We will also discuss some
potential further applications of our method.


title:
Complexity Leads to Simplicity: A Consensus Layer V Pyramidal Neuron Can
  Sustain Interpulse-Interval Coding

abstract:
  In terms of the long-distance communication of a single neuron, interpulse
intervals (IPIs) are a possible alternative to rate and binary codes. As a
proxy for IPI, the time-to-spike (TTS) for a neuron can be found in the
biophysical and experimental literature. Using the current, consensus layer V
pyramidal neuron, the present study examines the feasibility of IPI-coding and
examines the noise sources that limit the information rate of such an encoding.
In descending order of noise intensity, the noise sources are (i) synaptic
variability, (ii) sodium channel shot-noise, followed by (iii) thermal noise
with synaptic noise much greater than the sodium channel-noise. More
importantly, the biophysical model demonstrates a linear relationship between
input intensity and inverse TTS. This linear observation contradicts the
assumption that a neuron should be treated as a passive, electronic circuit (an
RC circuit, as in the Stein model). Finally, the biophysical simulations allow
the calculation of mutual information, which is about 3.0 bits/spike.


title:
Entropy Bumps and Another Sufficient Condition for the Two--Weight
  Boundedness of Sparse Operators

abstract:
  In this short note, we give a very efficient proof of a recent result of
Treil-Volberg and Lacey--Spencer giving sufficient conditions for the
two-weight boundedness of a sparse operator. We also give a new sufficient
condition for the two-weight boundedness of a sparse operator. We make critical
use of a formula of Hyt\"onen


title: Probing for Evidence of Plumes on Europa with HST/STIS

abstract:
  Roth et al (2014a) reported evidence for plumes of water venting from a
southern high latitude region on Europa - spectroscopic detection of off-limb
line emission from the dissociation products of water. Here, we present Hubble
Space Telescope (HST) direct images of Europa in the far ultraviolet (FUV) as
it transited the smooth face of Jupiter, in order to measure absorption from
gas or aerosols beyond the Europa limb. Out of ten observations we found three
in which plume activity could be implicated. Two show statistically significant
features at latitudes similar to Roth et al, and the third, at a more
equatorial location. We consider potential systematic effects that might
influence the statistical analysis and create artifacts, and are unable to find
any that can definitively explain the features, although there are reasons to
be cautious. If the apparent absorption features are real, the magnitude of
implied outgassing is similar to that of the Roth et al feature, however the
apparent activity appears more frequently in our data.


title: Critical thermalization of a disordered dipolar spin system in diamond

abstract:
  Statistical mechanics underlies our understanding of macroscopic quantum
systems. It is based on the assumption that out-of-equilibrium systems rapidly
approach their equilibrium states, forgetting any information about their
microscopic initial conditions. This fundamental paradigm is challenged by
disordered systems, in which a slowdown or even absence of thermalization is
expected. We report the observation of critical thermalization in a three
dimensional ensemble of $\sim 10^6$ electronic spins coupled via dipolar
interactions. By controlling the spin states of nitrogen vacancy color centers
in diamond, we observe slow, sub-exponential relaxation dynamics and identify a
regime of power-law decay with disorder-dependent exponents; this behavior is
modified at late times owing to many-body interactions. These observations are
quantitatively explained by a resonance counting theory that incorporates the
effects of both disorder and interactions.


title: Earthquake Number Forecasts Testing

abstract:
  We study the distributions of earthquake numbers in two global catalogs:
Global Centroid-Moment Tensor and Preliminary Determinations of Epicenters.
These distributions are required to develop the number test for forecasts of
future seismic activity rate. A common assumption is that the numbers are
described by the Poisson distribution. In contrast to the one-parameter Poisson
distribution, the negative-binomial distribution (NBD) has two parameters. The
second parameter characterizes the clustering or over-dispersion of a process.
We investigate the dependence of parameters for both distributions on the
catalog magnitude threshold and on temporal subdivision of catalog duration. We
find that for most cases of interest the Poisson distribution can be rejected
statistically at a high significance level in favor of the NBD. Therefore we
investigate whether these distributions fit the observed distributions of
seismicity. For this purpose we study upper statistical moments of earthquake
numbers (skewness and kurtosis) and compare them to the theoretical values for
both distributions. Empirical values for the skewness and the kurtosis increase
for the smaller magnitude threshold and increase with even greater intensity
for small temporal subdivision of catalogs. A calculation of the NBD skewness
and kurtosis levels shows rapid increase of these upper moments levels.
However, the observed catalog values of skewness and kurtosis are rising even
faster. This means that for small time intervals the earthquake number
distribution is even more heavy-tailed than the NBD predicts. Therefore for
small time intervals we propose using empirical number distributions
appropriately smoothed for testing forecasted earthquake numbers.


title:
Formulation of the twisted-light--matter interaction at the phase
  singularity: beams with strong magnetic fields

abstract:
  The formulation of the interaction of matter with singular light fields needs
special care. In a recent article [Phys.~Rev.~A {\bf 91}, 033808 (2015)] we
have shown that the Hamiltonian describing the interaction of a twisted light
beam having parallel orbital and spin angular momenta with a small object
located close to the phase singularity can be expressed only in terms of the
electric field of the beam. Here, we complement our studies by providing an
interaction Hamiltonian for beams having antiparallel orbital and spin angular
momenta. Such beams may exhibit unusually strong magnetic effects. We further
extend our formulation to radially and azimuthally polarized beams. The
advantages of our formulation are that for all beams the Hamiltonian is written
solely in terms of the electric and magnetic fields of the beam and as such it
is manifestly gauge-invariant. Furthermore it is intuitive by resembling the
well-known expressions in the dipole-electric and dipole-magnetic moment
approximations.


title: On Weakly Almost Periodic Measures

abstract:
  We study the diffraction and dynamical properties of translation bounded
weakly almost periodic measures. We prove that the dynamical hull of a weakly
almost periodic measure is a weakly almost periodic dynamical system with
unique minimal component given by the hull of the strongly almost periodic
component of the measure. In particular the hull is minimal if and only if the
measure is strongly almost periodic and the hull is always measurably conjugate
to a torus and has pure point spectrum with continuous eigenfunctions. As an
application we show the stability of the class of weighted Dirac combs with
Meyer set or FLC support and deduce that such measures have either trivial or
large pure point respectively continuous spectrum. We complement these results
by investigating the Eberlein convolution of two weakly almost periodic
measures. Here, we show that it is unique and a strongly almost periodic
measure. We conclude by studying the Fourier-Bohr coefficients of weakly almost
periodic measures.


title:
Probing dark energy with braneworld cosmology in the light of recent
  cosmological data

abstract:
  We investigate a brane model based on Randall-Sundrum scenarios with a
generic dark energy component. The latter drives the accelerated expansion at
late times of the Universe. In this scheme, extra terms are added into Einstein
Field equations that are propagated to the Friedmann equations. To constrain
the dark energy equation of state (EoS) and the brane tension we use
observational data with different energy levels (Supernovae type Ia, $H(z)$,
baryon acoustic oscillations, and cosmic microwave background radiation
distance, and a joint analysis) in a background cosmology. Beside EoS being
consistent with a cosmological constant at the $3\sigma$ confidence level for
each dataset, the baryon acoustic oscillations probe favors an EoS consistent
with a quintessence dark energy. Although we found different lower limit bounds
on the brane tension for each data sets, being the most restricted for CMB,
there is not enough evidence of modifications in the cosmological evolution of
the Universe by the existence of an extra dimension within observational
uncertainties. Nevertheless, these new bounds are complementary to those
obtained by other probes like table-top experiments, Big Bang Nucleosynthesis,
and stellar dynamics. Our results show that a further test of the braneworld
model with appropriate correction terms or a profound analysis with
perturbations, may be needed to improve the constraints provided by the current
data.


title:
Simultaneous Low-rank Component and Graph Estimation for
  High-dimensional Graph Signals: Application to Brain Imaging

abstract:
  We propose an algorithm to uncover the intrinsic low-rank component of a
high-dimensional, graph-smooth and grossly-corrupted dataset, under the
situations that the underlying graph is unknown. Based on a model with a
low-rank component plus a sparse perturbation, and an initial graph estimation,
our proposed algorithm simultaneously learns the low-rank component and refines
the graph. Our evaluations using synthetic and real brain imaging data in
unsupervised and supervised classification tasks demonstrate encouraging
performance.


title:
Transport gap engineering by contact geometry in graphene nanoribbons:
  Experimental and theoretical studies on artificial materials

abstract:
  Electron transport in small graphene nanoribbons is studied by microwave
emulation experiments and tight-binding calculations. In particular, it is
investigated under which conditions a transport gap can be observed. Our
experiments provide evidence that armchair ribbons of width $3m+2$ with integer
$m$ are metallic and otherwise semiconducting, whereas zigzag ribbons are
metallic independent of their width. The contact geometry, defining to which
atoms at the ribbon edges the source and drain leads are attached, has strong
effects on the transport. If leads are attached only to the inner atoms of
zigzag edges, broad transport gaps can be observed in all armchair ribbons as
well as in rhomboid-shaped zigzag ribbons. All experimental results agree
qualitatively with tight-binding calculations using the nonequilibrium Green's
function method.


title: Chemical Abundance Analysis of Moving Group W11450 (Latham 1)

abstract:
  We present elemental abundances for all seven stars in Moving Group W11450
(Latham 1) to determine if they may be chemically related. These stars appear
to be both spatially and kinematically related, but no spectroscopic abundance
analysis exists in literature. Abundances for eight elements were derived via
equivalent width analyses of high resolution (R $\sim$60,000), high
signal-to-noise ratio ($\langle$SNR$\rangle\sim$100) spectra obtained with the
Otto Struve 2.1m telescope and Sandiford Echelle Spectrograph at McDonald
Observatory. The large star-to-star scatter in metallicity, -0.55 $\leq$ [Fe/H]
$\leq$ 0.06 dex ($\sigma$= 0.25), implies these stars were not produced from
the same chemically homogeneous molecular cloud, and are therefore not part of
a remnant or open cluster as previously proposed. Prior to this analysis, it
was suggested that two stars in the group, W11449 & W11450, are possible wide
binaries. The candidate wide binary pair show similar chemical abundance
patterns with not only iron, but with other elements analyzed in this study,
suggesting the proposed connection between these two stars may be real.


title:
${\mathbb Z}_2\times {\mathbb Z}_2$-graded Lie Symmetries of the
  L\'evy-Leblond Equations

abstract:
  The first-order differential L\'evy-Leblond equations (LLE's) are the
non-relativistic analogs of the Dirac equation, being square roots of
($1+d$)-dimensional Schr\"odinger or heat equations. Just like the Dirac
equation, the LLE's possess a natural supersymmetry. In previous works it was
shown that non supersymmetric PDE's (notably, the Schr\"odinger equations for
free particles or in the presence of a harmonic potential), admit a natural
${\mathbb Z}_2$-graded Lie symmetry. In this paper we show that, for a certain
class of supersymmetric PDE's, a natural ${\mathbb Z}_2\times{\mathbb
Z}_2$-graded Lie symmetry appears. In particular, we exhaustively investigate
the symmetries of the $(1+1)$-dimensional L\'evy-Leblond Equations, both in the
free case and for the harmonic potential. In the free case a ${\mathbb
Z}_2\times{\mathbb Z}_2$-graded Lie superalgebra, realized by first and
second-order differential symmetry operators, is found. In the presence of a
non-vanishing quadratic potential, the Schr\"odinger invariance is maintained,
while the ${\mathbb Z}_2$- and ${\mathbb Z}_2\times{\mathbb Z}_2$- graded
extensions are no longer allowed. The construction of the ${\mathbb Z}_2\times
{\mathbb Z}_2$-graded Lie symmetry of the ($1+2$)-dimensional free heat LLE
introduces a new feature, explaining the existence of first-order differential
symmetry operators not entering the super Schr\"odinger algebra.


title: The Haar system as a Schauder basis in spaces of Hardy-Sobolev type

abstract:
  We show that, for suitable enumerations, the multivariate Haar system is a
Schauder basis in the classical Sobolev spaces on $\mathbb R^d$ with
integrability $1<p<\infty$ and smoothness $1/p-1<s<1/p$. This complements
earlier work by the last two authors on the unconditionality of the Haar system
and implies that it is a {conditional} Schauder basis for a nonempty open
subset of the $(1/p,s)$-diagram. The results extend to (quasi-)Banach spaces of
Hardy-Sobolev and Triebel-Lizorkin type in the range of parameters
$\frac{d}{d+1}<p<\infty$ and $\max\{d(1/p-1),1/p-1\}<s<\min\{1,1/p\}$, which is
optimal except perhaps at the end-points.


title: The quiver at the bottom of the twisted nilpotent cone on $\mathbb P^1$

abstract:
  For the moduli space of Higgs bundles on a Riemann surface of positive genus,
critical points of the natural Morse-Bott function lie along the nilpotent cone
of the Hitchin fibration and are representations of $\mbox{A}$-type quivers in
a twisted category of holomorphic bundles. The critical points that globally
minimize the function are representations of $\mbox{A}_1$. For twisted Higgs
bundles on the projective line, the quiver describing the bottom of the cone is
more complicated. We determine it here. We show that the moduli space is
topologically connected whenever the rank and degree are coprime, thereby
verifying conjectural lowest Betti numbers coming from high-energy physics.


title: Topological Data Analysis

abstract:
  Topological Data Analysis (TDA) can broadly be described as a collection of
data analysis methods that find structure in data. This includes: clustering,
manifold estimation, nonlinear dimension reduction, mode estimation, ridge
estimation and persistent homology. This paper reviews some of these methods.


title: Towards Scalable Network Delay Minimization

abstract:
  Reduction of end-to-end network delays is an optimization task with
applications in multiple domains. Low delays enable improved information flow
in social networks, quick spread of ideas in collaboration networks, low travel
times for vehicles on road networks and increased rate of packets in the case
of communication networks. Delay reduction can be achieved by both improving
the propagation capabilities of individual nodes and adding additional edges in
the network. One of the main challenges in such design problems is that the
effects of local changes are not independent, and as a consequence, there is a
combinatorial search-space of possible improvements. Thus, minimizing the
cumulative propagation delay requires novel scalable and data-driven
approaches.
  In this paper, we consider the problem of network delay minimization via node
upgrades. Although the problem is NP-hard, we show that probabilistic
approximation for a restricted version can be obtained. We design scalable and
high-quality techniques for the general setting based on sampling and targeted
to different models of delay distribution. Our methods scale almost linearly
with the graph size and consistently outperform competitors in quality.


title:
Spectral Properties of Harmonic Toeplitz Operators and Applications to
  the Perturbed Krein Laplacian

abstract:
  We consider harmonic Toeplitz operators $T_V = PV:{\mathcal H}(\Omega) \to
{\mathcal H}(\Omega)$ where $P: L^2(\Omega) \to {\mathcal H}(\Omega)$ is the
orthogonal projection onto ${\mathcal H}(\Omega) = \left\{u \in
L^2(\Omega)\,|\,\Delta u = 0 \; \mbox{in}\;\Omega\right\}$, $\Omega \subset
{\mathbb R}^d$, $d \geq 2$, is a bounded domain with $\partial \Omega \in
C^\infty$, and $V: \Omega \to {\mathbb C}$ is a suitable multiplier. First, we
complement the known criteria which guarantee that $T_V$ is in the $p$th
Schatten-von Neumann class $S_p$, by sufficient conditions which imply $T_V \in
S_{p, {\rm w}}$, the weak counterpart of $S_p$. Next, we assume that $\Omega$
is the unit ball in ${\mathbb R}^d$, and $V = \overline{V}$ is radially
symmetric, and investigate the eigenvalue asymptotics of $T_V$ if $V$ has a
power-like decay at $\partial \Omega$ or $V$ is compactly supported in
$\Omega$. Further, we consider general $\Omega$ and $V \geq 0$ which is regular
in $\Omega$, and admits a power-like decay of rate $\gamma > 0$ at $\partial
\Omega$, and we show that in this case $T_V$ is unitarily equivalent to a
pseudo-differential operator of order $-\gamma$, self-adjoint in $L^2(\partial
\Omega)$. Using this unitary equivalence, we obtain the main asymptotic term of
the eigenvalue counting function for the operator $T_V$. Finally, we introduce
the Krein Laplacian $K \geq 0$, self-adjoint in $L^2(\Omega)$; it is known that
${\rm Ker}\,K = {\mathcal H}(\Omega)$, and the zero eigenvalue of $K$ is
isolated. We perturb $K$ by $V \in C(\overline{\Omega};{\mathbb R})$, and show
that $\sigma_{\rm ess}(K+V) = V(\partial \Omega)$. Assuming that $V \geq 0$ and
$V{|\partial \Omega} = 0$, we study the asymptotic distribution of the
eigenvalues of $K \pm V$ near the origin, and find that the effective
Hamiltonian which governs this distribution is the Toeplitz operator $T_V$.


title: Proof of the HRT conjecture for almost every (1,3) configuration

abstract:
  Based on the proof of Demeter \We prove that for almost every (1,3)
configuration, there is no linear dependence between the associated
time-frequency translates of any $f\in L^2(\R)\backslash \{0\}$.cite{Dem10}, we
establish the HRT conjecture for almost every (1,3) configuration.


title: New properties for certain positive semidefinite matrices

abstract:
  We bring in some new notions associated with $2\times 2$ block positive
semidefinite matrices. These notions concern the inequalities between the
singular values of the off diagonal blocks and the eigenvalues of the
arithmetic mean or geometric mean of the diagonal blocks. We investigate some
relations between them. Many examples are included to illustrate these
relations.


title: Quantum Vacua of 2d Maximally Supersymmetric Yang-Mills Theory

abstract:
  We analyze the classical and quantum vacua of 2d $\mathcal{N}=(8,8)$
supersymmetric Yang-Mills theory with $SU(N)$ and $U(N)$ gauge group,
describing the worldvolume interactions of $N$ parallel D1-branes with flat
transverse directions $\mathbb{R}^8$. We claim that the IR limit of the $SU(N)$
theory in the superselection sector labeled $M \pmod{N}$ --- identified with
the internal dynamics of $(M,N)$-string bound states of Type IIB string theory
--- is described by the symmetric orbifold $\mathcal{N}=(8,8)$ sigma model into
$(\mathbb{R}^8)^{D-1}/\mathbb{S}_D$ when $D=\gcd(M,N)>1$, and by a single
massive vacuum when $D=1$, generalizing the conjectures of E. Witten and
others. The full worldvolume theory of the D1-branes is the $U(N)$ theory with
an additional $U(1)$ 2-form gauge field $B$ coming from the string theory
Kalb-Ramond field. This $U(N)+B$ theory has generalized field configurations,
labeled by the $\mathbb{Z}$-valued generalized electric flux and an independent
$\mathbb{Z}_N$-valued 't Hooft flux. We argue that in the quantum mechanical
theory, the $(M,N)$-string sector with $M$ units of electric flux has a
$\mathbb{Z}_N$-valued discrete $\theta$ angle specified by $M \pmod{N}$ dual to
the 't Hooft flux. Adding the brane center-of-mass degrees of freedom to the
$SU(N)$ theory, we claim that the IR limit of the $U(N) + B$ theory in the
sector with $M$ bound F-strings is described by the $\mathcal{N}=(8,8)$ sigma
model into ${\rm Sym}^{D} ( \mathbb{R}^8)$. We provide strong evidence for
these claims by computing an $\mathcal{N}=(8,8)$ analog of the elliptic genus
of the UV gauge theories and of their conjectured IR limit sigma models, and
showing they agree. Agreement is established by noting that the elliptic genera
are modular-invariant Abelian (multi-periodic and meromorphic) functions, which
turns out to be very restrictive.


title:
The M\"{o}bius transformation of continued fractions with bounded upper
  and lower partial quotients

abstract:
  Let $h$: $x\mapsto \frac{ax+b}{cx+d} $ be the nondegenerate M\"{o}bius
transformation with integer entries. We get a bound of the continued fraction
of $h(x)$ by the upper and lower bound of continued fraction of $x$, which
extends a result of Stambul \cite{S2}.


title:
Generation of concatenated Greenberger-Horne-Zeilinger-type entangled
  coherent state based on linear optics

abstract:
  The concatenated Greenberger-Horne-Zeilinger (C-GHZ) state is a new type of
multipartite entangled state, which has potential application in future quantum
information. In this paper, we propose a protocol of constructing arbitrary
C-GHZ entangled state approximatively. Different from the previous protocols,
each logic is encoded in the coherent state. This protocol is based on the
linear optics, which is feasible in experimental technology. This protocol may
be useful in quantum information based on the C-GHZ state.


title: Online Categorical Subspace Learning for Sketching Big Data with Misses

abstract:
  With the scale of data growing every day, reducing the dimensionality (a.k.a.
sketching) of high-dimensional data has emerged as a task of paramount
importance. Relevant issues to address in this context include the sheer volume
of data that may consist of categorical samples, the typically streaming format
of acquisition, and the possibly missing entries. To cope with these
challenges, the present paper develops a novel categorical subspace learning
approach to unravel the latent structure for three prominent categorical
(bilinear) models, namely, Probit, Tobit, and Logit. The deterministic Probit
and Tobit models treat data as quantized values of an analog-valued process
lying in a low-dimensional subspace, while the probabilistic Logit model relies
on low dimensionality of the data log-likelihood ratios. Leveraging the low
intrinsic dimensionality of the sought models, a rank regularized
maximum-likelihood estimator is devised, which is then solved recursively via
alternating majorization-minimization to sketch high-dimensional categorical
data `on the fly.' The resultant procedure alternates between sketching the new
incomplete datum and refining the latent subspace, leading to lightweight
first-order algorithms with highly parallelizable tasks per iteration. As an
extra degree of freedom, the quantization thresholds are also learned jointly
along with the subspace to enhance the predictive power of the sought models.
Performance of the subspace iterates is analyzed for both infinite and finite
data streams, where for the former asymptotic convergence to the stationary
point set of the batch estimator is established, while for the latter sublinear
regret bounds are derived for the empirical cost. Simulated tests with both
synthetic and real-world datasets corroborate the merits of the novel schemes
for real-time movie recommendation and chess-game classification.


title: Resonant transfer of large momenta from finite duration pulse sequences

abstract:
  We experimentally investigate the atom optics kicked particle at quantum
resonance using finite duration kicks. Even though the underlying process is
quantum interference it can be well described by an $\epsilon$-pseudoclassical
model. The $\epsilon$-pseudoclassical model agrees well with our experiments
for a wide range of parameters. We investigate the parameters yielding maximal
momentum transfer to the atoms and find that this occurs in the regime where
neither the short pulse approximation nor the Bragg condition is valid.
Nonetheless, the momentum transferred to the atoms can be predicted using a
simple scaling law, which provides a powerful tool for choosing optimal
experimental parameters. We demonstrate this in a measurement of the Talbot
time (from which $h/M$ can be deduced), in which we coherently split atomic
wave-functions into superpositions of momentum states that differ by 200 photon
recoils. Our work may provide a convenient way to implement large momentum
difference beam splitters in atom interferometers.


title:
Aligning Coordinated Text Streams through Burst Information Network
  Construction and Decipherment

abstract:
  Aligning coordinated text streams from multiple sources and multiple
languages has opened many new research venues on cross-lingual knowledge
discovery. In this paper we aim to advance state-of-the-art by: (1). extending
coarse-grained topic-level knowledge mining to fine-grained information units
such as entities and events; (2). following a novel
Data-to-Network-to-Knowledge (D2N2K) paradigm to construct and utilize network
structures to capture and propagate reliable evidence. We introduce a novel
Burst Information Network (BINet) representation that can display the most
important information and illustrate the connections among bursty entities,
events and keywords in the corpus. We propose an effective approach to
construct and decipher BINets, incorporating novel criteria based on
multi-dimensional clues from pronunciation, translation, burst, neighbor and
graph topological structure. The experimental results on Chinese and English
coordinated text streams show that our approach can accurately decipher the
nodes with high confidence in the BINets and that the algorithm can be
efficiently run in parallel, which makes it possible to apply it to huge
amounts of streaming data for never-ending language and information
decipherment.


title:
A volume preserving flow and the isoperimetric problem in warped product
  spaces

abstract:
  In this article, we continue the work in \cite{GL} and study a normalized
hypersurface flow in the more general ambient setting of warped product spaces.
This flow preserves the volume of the bounded domain enclosed by a graphical
hypersurface, and monotonically decreases the hypersurface area. As an
application, the isoperimetric problem in warped product spaces is solved for
such domains.


title:
On the influence of social bots in online protests. Preliminary findings
  of a Mexican case study

abstract:
  Social bots can affect online communication among humans. We study this
phenomenon by focusing on #YaMeCanse, the most active protest hashtag in the
history of Twitter in Mexico. Accounts using the hashtag are classified using
the BotOrNot bot detection tool. Our preliminary analysis suggests that bots
played a critical role in disrupting online communication about the protest
movement.