title: Improving FPGA resilience through Partial Dynamic Reconfiguration

abstract:
  This paper explores advances in reconfiguration properties of SRAM-based
FPGAs, namely Partial Dynamic Reconfiguration, to improve the resilience of
critical systems that take advantage of this technology. Commercial
of-the-shelf state-of-the-art FPGA devices use SRAM cells for the configuration
memory, which allow an increase in both performance and capacity. The fast
access times and unlimited number of writes of this technology, reduces
reconfiguration delays and extends the device lifetime but, at the same time,
makes them more sensitive to radiation effects, in the form of Single Event
Upsets. To overcome this limitation, manufacturers have proposed a few fault
tolerant approaches, which rely on space/time redundancy and configuration
memory content recovery - scrubbing. In this paper, we first present radiation
effects on these devices and investigate the applicability of the most commonly
used fault tolerant approaches, and then propose an approach to improve FPGA
resilience, through the use of a less intrusive failure prediction scrubbing.
It is expected that this approach relieves the system designer from
dependability concerns and reduces both time intrusiveness and overall power
consumption.


title:
Evolution of states and mesoscopic scaling for two-component
  birth-and-death dynamics in continuum

abstract:
  Two coupled spatial birth-and-death Markov evolutions on $\mathbb{R}^d$ are
obtained as unique weak solutions to the associated Fokker-Planck equations.
Such solutions are constructed by its associated sequence of correlation
functions satisfying the so-called Ruelle-bound. Using the general scheme of
Vlasov scaling we are able to derive a system of non-linear, non-local
mesoscopic equations describing the effective density of the particle system.
The results are applied to several models of ecology and biology.


title: Extension of Friedel's law to Vortex Beam Diffraction

abstract:
  Friedel's law states that the modulus of the Fourier transform of real
functions is centrosymmetric, while the phase is antisymmetric. As a
consequence of this, elastic scattering of plane wave photons or electrons
within the first-order Born-approximation as well as Fraunhofer diffraction on
any aperture, is bound to result in centrosymmetric diffraction patterns.
Friedel's law, however, does not apply for vortex beams, and centrosymmetry in
general is not present in their diffraction patterns. In this work we extend
Friedel's law for vortex beams by showing that the diffraction patterns of
vortex beams with opposite topological charge, scattered on the same two
dimensional potential, always are centrosymmetric to one another, regardless of
the symmetry of the scattering object. We verify our statement by means of
numerical simulations and experimental data. Our research provides deeper
understanding in vortex beam diffraction and can be used to design new
experiments to measure the topological charge of vortex beams with diffraction
gratings, or study general vortex beam diffraction.


title:
Statistical Mechanics of On-line Ensemble Teacher Learning through a
  Novel Perceptron Learning Rule

abstract:
  In ensemble teacher learning, ensemble teachers have only uncertain
information about the true teacher, and this information is given by an
ensemble consisting of an infinite number of ensemble teachers whose variety is
sufficiently rich. In this learning, a student learns from an ensemble teacher
that is iteratively selected randomly from a pool of many ensemble teachers. An
interesting point of ensemble teacher learning is the asymptotic behavior of
the student to approach the true teacher by learning from ensemble teachers.
The student performance is improved by using the Hebbian learning rule in the
learning. However, the perceptron learning rule cannot improve the student
performance. On the other hand, we proposed a perceptron learning rule with a
margin. This learning rule is identical to the perceptron learning rule when
the margin is zero and identical to the Hebbian learning rule when the margin
is infinity. Thus, this rule connects the perceptron learning rule and the
Hebbian learning rule continuously through the size of the margin. Using this
rule, we study changes in the learning behavior from the perceptron learning
rule to the Hebbian learning rule by considering several margin sizes. From the
results, we show that by setting a margin of kappa > 0, the effect of an
ensemble appears and becomes significant when a larger margin kappa is used.


title:
Algorithms for the Iterative Estimation of Discrete-Valued Sparse
  Vectors

abstract:
  In Compressed Sensing, a real-valued sparse vector has to be estimated from
an underdetermined system of linear equations. In many applications, however,
the elements of the sparse vector are drawn from a finite set. For the
estimation of these discrete-valued vectors, matched algorithms are required
which take the additional knowledge of the discrete nature into account. In
this paper, the estimation problem is treated from a communications engineering
point of view. A powerful new algorithm incorporating techniques known from
digital communications and information theory is derived. For comparison, Turbo
Compressed Sensing is adapted to the discrete setup and a simplified and
generalized notation is presented. The performance of the algorithms is covered
by numerical simulations.


title:
On Densities of the Product, Quotient and Power of Independent
  Subordinators

abstract:
  We obtain the closed form expressions for the densities of the product,
quotient, power and scalar multiple of independent stable subordinators.
Similar results for the independent inverse stable subordinators are discussed.
This is achieved by expressing the densities of stable and inverse stable
subordinators in terms of the Fox's $H$-function.


title:
Pulsed Cathodoluminescence Spectra of Solid Oxides with Low
  Concentrations of Optically-Active Impurities

abstract:
  Pulsed cathodoluminescence (PCL) spectra of ultra-pure SiO2, GeO2, SnO2,
TiO2, La2O3, Y2O3, Sc2O3, CaCO3 powders and {\alpha}-quartz, Ca:YVO4, LiNbO3
and Sc:LiNbO3 crystals were studied under the same experimental conditions. It
was found that PCL spectra of SiO2, SnO2, GeO2, TiO2, La2O3 and CaCO3 powders
contain a common band with maximum intensity at 500 nm, PCL spectra of samples
Y2O3, Sc2O3, PbWO4 and Ca:YVO4 contain a common band at 490 nm and PCL spectra
of LiNbO3 and Sc:LiNbO3 crystals contain a common band at 507 nm. It was found
that the average intensity of the PCL spectra and position of the maximum
intensity of these common bands depend on the type of a band gap transition of
the material. We suppose that these common bands have the same origin in PCL
spectra of all the materials studied and are related to recombination of
O2--O-oxygen complexes. These complexes appear in the vicinities of anionic and
cationic vacancies, where the geometry and orientation of coordination
polyhedrons are violated due to the stress in the lattice.


title:
Orbiter-to-orbiter tomography: a potential approach for small planetary
  objects

abstract:
  The goal of this paper is to advance mathematical and computational
methodology for orbiter-to-orbiter radio tomography of small planetary objects.
In this study, an advanced full waveform forward model is coupled with a total
variation based inversion technique. We use a satellite formation model in
which a single unit receives a signal that is transmitted by one or more
transponder satellites. Numerical results for a 2D domain are presented.


title: High-Quality Synthesis Against Stochastic Environments

abstract:
  In the classical synthesis problem, we are given an LTL formula psi over sets
of input and output signals, and we synthesize a transducer that realizes psi.
One weakness of automated synthesis in practice is that it pays no attention to
the quality of the synthesized system. Indeed, the classical setting is
Boolean: a computation satisfies a specification or does not satisfy it.
Accordingly, while the synthesized system is correct, there is no guarantee
about its quality. In recent years, researchers have considered extensions of
the classical Boolean setting to a quantitative one. The logic LTL[F] is a
multi-valued logic that augments LTL with quality operators. The satisfaction
value of an LTL[F] formula is a real value in [0,1], where the higher the value
is, the higher is the quality in which the computation satisfies the
specification.
  Decision problems for LTL become search or optimization problems for LFL[F].
In particular, in the synthesis problem, the goal is to generate a transducer
that satisfies the specification in the highest possible quality.
  Previous work considered the worst-case setting, where the goal is to
maximize the quality of the computation with the minimal quality. We introduce
and solve the stochastic setting, where the goal is to generate a transducer
that maximizes the expected quality of a computation, subject to a given
distribution of the input signals. Thus, rather than being hostile, the
environment is assumed to be probabilistic, which corresponds to many realistic
settings. We show that the problem is 2EXPTIME-complete, like classical LTL
synthesis, and remains so in two extensions we consider: one that maximizes the
expected quality while guaranteeing that the minimal quality is, with
probability $1$, above a given threshold, and one that allows assumptions on
the environment.


title: Cluster algebras and continued fractions

abstract:
  We establish a combinatorial realization of continued fractions as quotients
of cardinalities of sets. These sets are sets of perfect matchings of certain
graphs, the snake graphs, that appear naturally in the theory of cluster
algebras. To a continued fraction $[a_1,a_2,\ldots,a_n]$, we associate a snake
graph $\mathcal{G}[a_1,a_2,\ldots,a_n]$ such that the continued fraction is the
quotient of the number of perfect matchings of
$\mathcal{G}[a_1,a_2,\ldots,a_n]$ and $\mathcal{G}[a_2,\ldots,a_n]$. We also
show that snake graphs are in bijection with continued fractions.
  We then apply this connection between cluster algebras and continued
fractions in two directions. First, we use results from snake graph calculus to
obtain new identities for the continuants of continued fractions. Then, we
apply the machinery of continued fractions to cluster algebras and obtain
explicit direct formulas for quotients of elements of the cluster algebra as
continued fractions of Laurent polynomials in the initial variables. Building
on this formula, and using classical methods for infinite periodic continued
fractions, we also study the asymptotic behavior of quotients of elements of
the cluster algebra.


title:
Dynamical generation of hadronic resonances in effective models with
  derivative interactions

abstract:
  Light scalar mesons can be understood as dynamically generated resonances.
They arise as 'companion poles' in the propagators of quark-antiquark seed
states when accounting for hadronic loop contributions to the self-energies of
the latter. Such a mechanism may explain the overpopulation in the scalar
sector - there exist more resonances with total spin $J=0$ than can be
described within a quark model.
  Along this line, we study an effective Lagrangian approach where the
isovector state $a_{0}(1450)$ couples via both non-derivative and derivative
interactions to pseudoscalar mesons. It is demonstrated that the propagator has
two poles: a companion pole corresponding to $a_{0}(980)$ and a pole of the
seed state $a_{0}(1450)$. The positions of these poles are in quantitative
agreement with experimental data. Besides that, we investigate similar models
for the isodoublet state $K_{0}^{\ast}(1430)$ by performing a fit to $\pi K$
phase shift data in the $I=1/2,$ $J=0$ channel. We show that, in order to fit
the data accurately, a companion pole for the $K_{0}^{\ast}(800)$, that is, the
light $\kappa$, is required. A large-$N_{c}$ study confirms that both
resonances below $1$ GeV are predominantly four-quark states, while the heavy
states are quarkonia.


title: Serre weights and Breuil's lattice conjecture in dimension three

abstract:
  We prove in generic situations that the lattice in a tame type induced by the
completed cohomology of a $U(3)$-arithmetic manifold is purely local, i.e.,
only depends on the Galois representation at places above $p$. This is a
generalization to $\mathrm{GL}_3$ of the lattice conjecture of Breuil. In the
process, we also prove the geometric Breuil-M\'ezard conjecture for (tamely)
potentially crystalline deformation rings with Hodge-Tate weights $(0,1,2)$ as
well as the Serre weight conjectures over an unramified field extending our
previous results. We also prove results in modular representation theory about
lattices in Deligne-Luzstig representations for the group
$\mathrm{GL}_3(\mathbb{F}_q)$.


title:
Control of pseudodifferential operators by maximal functions via
  weighted inequalities

abstract:
  We establish general weighted $L^2$ inequalities for pseudodifferential
operators associated to the H\"ormander symbol classes $S^m_{\rho,\delta}$.
Such inequalities allow to control these operators by fractional
"non-tangential" maximal functions, and subsume the optimal range of Lebesgue
space bounds for pseudodifferential operators. As a corollary, several known
Muckenhoupt type bounds are recovered, and new bounds for weights lying in the
intersection of the Muckenhoupt and reverse H\"older classes are obtained. The
proof relies on a subdyadic decomposition of the frequency space, together with
applications of the Cotlar-Stein almost orthogonality principle and a
quantitative version of the symbolic calculus.


title: Do electromagnetic waves always propagate along null geodesics?

abstract:
  We find exact solutions to Maxwell equations written in terms of four-vector
potentials in non--rotating, as well as in G\"odel and Kerr spacetimes. We show
that Maxwell equations can be reduced to two uncoupled second-order
differential equations for combinations of the components of the four-vector
potential. Exact electromagnetic waves solutions are written on given
gravitational field backgrounds where they evolve. We find that in
non--rotating spherical symmetric spacetimes, electromagnetic waves travel
along null geodesics. However, electromagnetic waves on G\"odel and Kerr
spacetimes do not exhibit that behavior.


title:
Standard transmutation operators for the one dimensional Schr\"odinger
  operator with a locally integrable potential

abstract:
  We study a special class of operators T satisfying the transmutation relation
(Tu)"-qTu=Tu" in the sense of distributions, where q is a locally integrable
function, and u belongs to a suitable space of distributions depending on the
smoothness properties of q. A method which allows one to construct a
fundamental set of transmutation operators of this class in terms of a single
particular transmutation operator is presented. Moreover, following [27], we
show that a particular transmutation operator can be realized as a Volterra
integral operator of the second kind. We study the boundedness and
invertibility properties of the transmutation operators, and used it to obtain
a representation for the general distributional solution of the equation
u"-qu=zu, in terms of the general solution of the same equation with z=0.


title:
Towards Designing PLC Networks for Ubiquitous Connectivity in
  Enterprises

abstract:
  Powerline communication (PLC) provides inexpensive, secure and high speed
network connectivity, by leveraging the existing power distribution networks
inside the buildings. While PLC technology has the potential to improve
connectivity and is considered a key enabler for sensing, control, and
automation applications in enterprises, it has been mainly deployed for
improving connectivity in homes. Deploying PLCs in enterprises is more
challenging since the power distribution network is more complex as compared to
homes. Moreover, existing PLC technologies such as HomePlug AV have not been
designed for and evaluated in enterprise deployments. In this paper, we first
present a comprehensive measurement study of PLC performance in enterprise
settings, by analyzing PLC channel characteristics across space, time, and
spectral dimensions, using commodity HomePlug AV PLC devices. Our results
uncover the impact of distribution lines, circuit breakers, AC phases and
electrical interference on PLC performance. Based on our findings, we show that
careful planning of PLC network topology, routing and spectrum sharing can
significantly boost performance of enterprise PLC networks. Our experimental
results show that multi-hop routing can increase throughput performance by 5x
in scenarios where direct PLC links perform poorly. Moreover, our trace driven
simulations for multiple deployments, show that our proposed fine-grained
spectrum sharing design can boost the aggregated and per-link PLC throughput by
more than 20% and 100% respectively, in enterprise PLC networks.


title: The Allen-Cahn equation on closed manifolds

abstract:
  We study global variational properties of the space of solutions to
$-\varepsilon^2\Delta u + W'(u)=0$ on any closed Riemannian manifold $M$. Our
techniques are inspired by recent advances in the variational theory of minimal
hypersurfaces and extend a well-known analogy with the theory of phase
transitions. First, we show that solutions at the lowest positive energy level
are either stable or obtained by min-max and have index 1. We show that if
$\varepsilon$ is not small enough, in terms of the Cheeger constant of $M$,
then there are no interesting solutions. However, we show that the number of
min-max solutions to the equation above goes to infinity as $\varepsilon\to 0$
and their energies have sublinear growth. This result is sharp in the sense
that for generic metrics the number of solutions is finite, for fixed
$\varepsilon$, as shown recently by G. Smith. We also show that the energy of
the min-max solutions accumulate, as $\varepsilon \to 0$, around
limit-interfaces which are smooth embedded minimal hypersurfaces whose area
with multiplicity grows sublinearly. For generic metrics with ${\rm Ric}_M>0$,
the limit-interface of the solutions at the lowest positive energy level is an
embedded minimal hypersurface of least area in the sense of Mazet-Rosenberg.
Finally, we prove that the min-max energy values are bounded from below by the
widths of the area functional as defined by Marques-Neves.


title: From topological field theory to deformation quantization and reduction

abstract:
  This note describes the functional-integral quantization of two-dimensional
topological field theories together with applications to problems in
deformation quantization of Poisson manifolds and reduction of certain
submanifolds. A brief introduction to smooth graded manifolds and to the
Batalin-Vilkovisky formalism is included.


title:
Massively parallel simulations of relativistic fluid dynamics on
  graphics processing units with CUDA

abstract:
  Relativistic fluid dynamics is a major component in dynamical simulations of
the quark-gluon plasma created in relativistic heavy-ion collisions.
Simulations of the full three-dimensional dissipative dynamics of the
quark-gluon plasma with fluctuating initial conditions are computationally
expensive and typically require some degree of parallelization. In this paper,
we present a GPU implementation of the Kurganov-Tadmor algorithm which solves
the 3+1d relativistic viscous hydrodynamics equations including the effects of
both bulk and shear viscosities. We demonstrate that the resulting CUDA-based
GPU code is approximately two orders of magnitude faster than the corresponding
serial implementation of the Kurganov-Tadmor algorithm. We validate the code
using (semi-)analytic tests such as the relativistic shock-tube and Gubser
flow.


title:
Analytical parametrization and shape classification of anomalous HH
  production in the EFT approach

abstract:
  In this document we study the effect of anomalous Higgs boson couplings on
non-resonant pair production of Higgs bosons ($HH$) at the LHC. We explore the
space of the five parameters $\kappa_{\lambda}$, $\kappa_{t}$, $c_2$, $c_g$,
and $c_{2g}$ in terms of the corresponding kinematics of the final state, and
describe a partition of the space into a limited number of regions featuring
similar phenomenology in the kinematics of $HH$ final state. We call clusters
the sets of points belonging to the same region; to each cluster corresponds a
representative point which we call a benchmark. We discuss a possible technique
to estimate the sensitivity of an experimental search to the kinematical
differences between the phenomenology of the benchmark points and the rest of
the parameter space contained in the corresponding cluster. We also provide an
analytical parametrization of the cross-section modifications that the
variation of anomalous couplings produces with respect to standard model $HH$
production along with a recipe to translate the results into other
parameter-space bases. Finally, we provide a preliminary analysis of variations
in the topology of the final state within each region based on recent LHC
results.


title: Quantum Correlations in NMR systems

abstract:
  In conventional NMR experiments, the Zeeman energy gaps of the nuclear spin
ensembles are much lower than their thermal energies, and accordingly exhibit
tiny polarizations. Generally such low-purity quantum states are devoid of
quantum entanglement. However, there exist certain nonclassical correlations
which can be observed even in such systems. In this chapter, we discuss three
such quantum correlations, namely, quantum contextuality, Leggett-Garg temporal
correlations, and quantum discord. In each case, we provide a brief theoretical
background and then describe some results from NMR experiments.


title: Communication complexity of approximate Nash equilibria

abstract:
  For a constant $\epsilon$, we prove a poly(N) lower bound on the (randomized)
communication complexity of $\epsilon$-Nash equilibrium in two-player NxN
games. For n-player binary-action games we prove an exp(n) lower bound for the
(randomized) communication complexity of $(\epsilon,\epsilon)$-weak approximate
Nash equilibrium, which is a profile of mixed actions such that at least
$(1-\epsilon)$-fraction of the players are $\epsilon$-best replying.


title: Fathom: Reference Workloads for Modern Deep Learning Methods

abstract:
  Deep learning has been popularized by its recent successes on challenging
artificial intelligence problems. One of the reasons for its dominance is also
an ongoing challenge: the need for immense amounts of computational power.
Hardware architects have responded by proposing a wide array of promising
ideas, but to date, the majority of the work has focused on specific algorithms
in somewhat narrow application domains. While their specificity does not
diminish these approaches, there is a clear need for more flexible solutions.
We believe the first step is to examine the characteristics of cutting edge
models from across the deep learning community.
  Consequently, we have assembled Fathom: a collection of eight archetypal deep
learning workloads for study. Each of these models comes from a seminal work in
the deep learning community, ranging from the familiar deep convolutional
neural network of Krizhevsky et al., to the more exotic memory networks from
Facebook's AI research group. Fathom has been released online, and this paper
focuses on understanding the fundamental performance characteristics of each
model. We use a set of application-level modeling tools built around the
TensorFlow deep learning framework in order to analyze the behavior of the
Fathom workloads. We present a breakdown of where time is spent, the
similarities between the performance profiles of our models, an analysis of
behavior in inference and training, and the effects of parallelism on scaling.


title:
Approximation and inference methods for stochastic biochemical kinetics
  - a tutorial review

abstract:
  Stochastic fluctuations of molecule numbers are ubiquitous in biological
systems. Important examples include gene expression and enzymatic processes in
living cells. Such systems are typically modelled as chemical reaction networks
whose dynamics are governed by the Chemical Master Equation. Despite its simple
structure, no analytic solutions to the Chemical Master Equation are known for
most systems. Moreover, stochastic simulations are computationally expensive,
making systematic analysis and statistical inference a challenging task.
Consequently, significant effort has been spent in recent decades on the
development of efficient approximation and inference methods. This article
gives an introduction to basic modelling concepts as well as an overview of
state of the art methods. First, we motivate and introduce deterministic and
stochastic methods for modelling chemical networks, and give an overview of
simulation and exact solution methods. Next, we discuss several approximation
methods, including the chemical Langevin equation, the system size expansion,
moment closure approximations, time-scale separation approximations and hybrid
methods. We discuss their various properties and review recent advances and
remaining challenges for these methods. We present a comparison of several of
these methods by means of a numerical case study and highlight some of their
respective advantages and disadvantages. Finally, we discuss the problem of
inference from experimental data in the Bayesian framework and review recent
methods developed the literature. In summary, this review gives a
self-contained introduction to modelling, approximations and inference methods
for stochastic chemical kinetics.

categories: q-bio.QM cond-mat.stat-mech physics.bio-ph q-bio.MN stat.ML


title: Syntax and analytic semantics of LISA

abstract:
  We provide the syntax and semantics of the LISA (for "Litmus Instruction Set
Architecture") language. The parallel assembly language LISA is implemented in
the herd7 tool (http://virginia.cs.ucl.ac.uk/herd/) for simulating weak
consistency models.


title: Hamilton-Jacobi approach to Potential Functions in Information Geometry

abstract:
  The search for a potential function $S$ allowing to reconstruct a given
metric tensor $g$ and a given symmetric covariant tensor $T$ on a manifold
$\mathcal{M}$ is formulated as the Hamilton-Jacobi problem associated with a
canonically defined Lagrangian on $T\mathcal{M}$. The connection between this
problem, the geometric structure of the space of pure states of quantum
mechanics, and the theory of contrast functions of classical information
geometry is outlined.


title:
HIFLUGCS: X-ray luminosity -- dynamical mass relation and its
  implications for mass calibrations with the SPIDERS and 4MOST surveys

abstract:
  We present the X-ray luminosity (L) versus dynamical mass (M) relation for 63
nearby clusters in the HIFLUGCS. The luminosity measurements are obtained based
on ~1.3 Ms of clean XMM data and ROSAT pointed observations. The masses are
estimated using optical spectroscopic redshifts of 13647 cluster galaxies in
total. Given sufficient numbers of member galaxies in computing the dynamical
masses, the L-M relations agree between the disturbed and undisturbed clusters.
The cool-core clusters still dominate the scatter in the L-M relation even when
a core corrected X-ray luminosity is used, which indicates that the scatter
mainly reflects the structure formation history of the clusters. As shown by
the clusters with a small number of redshifts, the dynamical masses can be
underestimated leading to a biased scaling relation. To investigate the
potential of spectroscopic surveys to follow up high-redshift galaxy
clusters/groups observed in X-ray surveys for the identifications and mass
calibrations, we carried out Monte-Carlo re-sampling of the cluster galaxy
redshifts and calibrated the uncertainties of the redshift and dynamical mass
estimates when only reduced numbers of galaxy redshifts per cluster are
available. The re-sampling considers the SPIDERS and 4MOST configurations,
designed for the follow-up of the eROSITA clusters, and was carried out for
each cluster at the actual cluster redshift as well as at z=0.2, 0.4, 0.6, and
0.8. For following up very distant cluster/groups, we carried out the mass
calibration based on the re-sampling with only 10zs/cluster, and redshift
calibration based on the re-sampling with only 5zs/cluster and 10zs/cluster,
respectively. Our results demonstrate the power of combining upcoming X-ray and
optical spectroscopic surveys for mass calibration. The scatter in the
dynamical mass estimates for the clusters with at least ten members is within
50%.


title: Speckle interferometry of secondary components in nearby visual binaries

abstract:
  Statistical characterization of secondary subsystems in binaries helps to
distinguish between various scenarios of multiple-star formation. The DSSI
speckle instrument was used at the Gemini-N telescope for several hours in 2015
July to probe binarity of 25 secondary components in nearby solar-type
binaries. Six new subsystems were resolved, with meaningful detection limits
for the remaining targets. The large incidence of secondary subsystems agrees
with other similar studies. The newly resolved subsystem HIP 115417 Ba,Bb
causes deviations in the observed motion of the outer binary from which an
astrometric orbit of Ba,Bb with a period of 117 years is deduced.


title:
Evidence for trivial Berry phase and absence of chiral anomaly in
  semimetal NbP

abstract:
  We report a detailed magneto-transport study in single crystals of NbP. High
quality crystals were grown by vapour transport method. An exceptionally large
magnetoresistance is confirmed at low temperature which is non-saturating and
is linear at high fields. Models explaining the linear magnetoresistance are
discussed and it is argued that in NbP this is linked to charge carrier
mobility fluctuations. Negative longitudinal magnetoresistance is not seen,
unlike several other Weyl monopnictides, suggesting lack of well defined chiral
anomaly in NbP. Unambiguous Shubnikov-de-Haas oscillations are observed at low
temperatures that are correlated to Berry phases. The Landau fan diagram
indicates trivial Berry phase in NbP crystals corresponding to Fermi surface
extrema at 30.5 Tesla.


title:
Tuning Edge States in Strained-Layer InAs/GaInSb Quantum Spin Hall
  Insulators

abstract:
  We report on a class of quantum spin Hall insulators (QSHIs) in
strained-layer InAs/GaInSb quantum wells, in which the bulk gaps are enhanced
by up to five folds as compared to the binary InAs/GaSb QSHI. Remarkably, with
consequently increasing edge velocity, the edge conductance at zero and applied
magnetic fields manifests time reversal symmetry (TRS) -protected properties
consistent with Z2 topological insulator. The InAs/GaInSb bilayers offer a much
sought-after platform for future studies and applications of the QSHI.


title:
Relating Mass to Angular Momentum and Charge in 5-Dimensional Minimal
  Supergravity

abstract:
  We prove a mass-angular momentum-charge inequality for a broad class of
maximal, asymptotically flat, bi-axisymmetric initial data within the context
of five-dimensional minimal supergravity. We further show that the charged
Myers-Perry black hole initial data are the unique minimizers. In addition, we
establish a rigidity statement for the relevant BPS bound, and give a
variational characterization of BMPV black holes.


title:
Identification of Bifurcations from Observations of Noisy Biological
  Oscillators

abstract:
  Hair bundles are biological oscillators that actively transduce mechanical
stimuli into electrical signals in the auditory, vestibular, and lateral-line
systems of vertebrates. A bundle's function can be explained in part by its
operation near a particular type of bifurcation, a qualitative change in
behavior. By operating near different varieties of bifurcation, the bundle
responds best to disparate classes of stimuli. We show how to determine the
identity of and proximity to distinct bifurcations despite the presence of
substantial environmental noise.


title:
Determination of contrast factors for cubic slip-systems and their
  application in the microstructural characterization of binary Fm$\bar{3}$m
  materials

abstract:
  The stress-strain anisotropy -including both elastic properties and
dislocation distributions- of crystalline systems can be studied using a
dislocation model proposed by Ung\'ar and Borb\'ely. However this model
requires fundamental parameters (i.e., contrast factors), which take into
account both the elastic properties and symmetry for each system. In this
study, such contrast factors were calculated from first principles for cubic
slip-systems through the evaluation of the distortion tensor in a
dislocation-dependent coordinate set. Moreover, a straightforward expression
for the computation of contrast factors is provided. Further analysis of the
microstructural parameters was carried out using the modified Williamson-Hall
method to characterize rock-salt materials.


title:
Application of Public Ledgers to Revocation in Distributed Access
  Control

abstract:
  There has recently been a flood of interest in potential new applications of
blockchains, as well as proposals for more generic designs called public
ledgers. Most of the novel proposals have been in the financial sector.
However, the public ledger is an abstraction that solves several of the
fundamental problems in the design of secure distributed systems: global time
in the form of a strict linear order of past events, globally consistent and
immutable view of the history, and enforcement of some application-specific
safety properties. This paper investigates the applications of public ledgers
to access control and, more specifically, to group management in distributed
systems where entities are represented by their public keys and authorization
is encoded into signed certificates. It is particularly difficult to handle
negative information, such as revocation of certificates or group membership,
in the distributed setting. The linear order of events and global consistency
simplify these problems, but the enforcement of internal constraints in the
ledger implementation often presents problems. We show that different types of
revocation require slightly different properties from the ledger. We compare
the requirements with Bitcoin, the best known blockchain, and describe an
efficient ledger design for membership revocation that combines ideas from
blockchains and from web-PKI monitoring. While we use certificate-based
group-membership management as the case study, the same ideas can be applied
more widely to rights revocation in distributed systems.


title: An iteration based on prime and composite factors

abstract:
  A discrete map based on the sum of an integer's distinct primes factors and
the sum of its other factors is defined and its iteration is studied.


title:
Spatio-temporal dynamics of sources of hard X-ray pulsations in solar
  flares

abstract:
  We present systematic analysis of spatio-temporal evolution of sources of
hard X-ray (HXR) pulsations in solar flares. We concentrate on disk flares
whose impulsive phase are accompanied by a series of more than three peaks
(pulsations) of HXR emission detected in the RHESSI 50-100 keV channel with
4-second cadence. 29 such flares observed from February 2002 to June 2015 with
time differences between successive peaks of 8-270 s are studied. The main
observational result is that sources of HXR pulsations in all flares are not
stationary, they demonstrate apparent displacements from pulsation to
pulsation. The flares can be subdivided into two groups depending on character
of dynamics of HXR sources. The group-1 consists of 16 flares (55%) with
systematic dynamics of HXR sources from pulsation to pulsation with respect to
a magnetic polarity inversion line (MPIL), which has simple extended trace on
the photosphere. The group-2 consists of 13 flares (45%) with more chaotic
displacements of HXR sources with respect to an MPIL having more complicated
structure. Based on the observations we conclude that the mechanism of flare
HXR pulsations is related to successive triggering of energy release in
different magnetic loops. Group-1 flare regions consist of loops stacked into
magnetic arcades extended along MPILs. Group-2 flare regions have more
complicated magnetic structures and loops are arranged more chaotically. We
also found that at least 14 (88%) group-1 flares and 11 (85%) group-2 flares
are accompanied by coronal mass ejections, i.e. the majority of flares studied
are eruptive events. This gives an indication that eruptive processes play
important role in generation of HXR pulsations. We suggest that an erupting
flux rope can act as a trigger of energy release. Its successive interaction
with different loops can lead to apparent motion of HXR sources and to a series
of HXR pulsations.


title: Local freeness in frame bundle prolongations of $C^\infty$ actions

abstract:
  Let $G$~be a real Lie group and let $G^\circ$ be the identity component
of~$G$. Let $G$~act on a $C^\infty$ real manifold~$M$. Assume the action is
$C^\infty$. Assume that the fixpoint set of any nontrivial element of~$G^\circ$
has empty interior in~$M$. Let $n:=\dim G$. Assume $n\ge1$. Let $F$ be the
frame bundle of~$M$ of order $n-1$. We prove: there exists a $G$-invariant
dense open subset~$Q$ of~$F$ such that the $G$-action on $Q$ has discrete
stabilizers.


title: Diagonal gates in the Clifford hierarchy

abstract:
  The Clifford hierarchy is a set of gates that appears in the theory of
fault-tolerant quantum computation, but its precise structure remains elusive.
We give a complete characterization of the diagonal gates in the Clifford
hierarchy for prime-dimensional qudits. They turn out to be $p^{m}$-th roots of
unity raised to polynomial functions of the basis state to which they are
applied, and we determine which level of the Clifford hierarchy a given gate
sits in based on $m$ and the degree of the polynomial.


title:
Matter neutrino oscillations, an approximation in a parametrization-free
  framework

abstract:
  Neutrino oscillations are one of the most studied and successful phenomena
since the establishment of the solar neutrino problem in late 1960's. In this
work we discuss the exact expressions for the probability P_{\alpha\beta} in a
constant density medium, in terms of the standard vacuum parameters and the
medium density. Besides of being compact, these expressions are independent of
any particular parametrization, which could be helpful in the application of
unitary tests of the mixing matrix. In addition, we introduce a new
approximation on P_{\alpha\beta} and compare it with the most commonly used,
discussing their main differences.


title: Comment concerning Leonardo's rule

abstract:
  In this comment we propose a novel explanation for the Leonardo's rule
concerning the tree branching. According to Leonardo's notebooks he observed
that if one observes the branches of a tree, the squared radius of the
principal branch is equal to the sum of the squared radius of the branch
daughters.


title:
Long Time Existence of the Cross Curvature Flow in 3-Manifolds with
  Negative Sectional Curvature

abstract:
  Given a closed 3-manifold with an initial Riemannian metric of negative sec-
tional curvature, we consider the cross curvature flow an evolution equation of
metric on M3. We prove long-time existence of a solution to the cross curvature
flow via the maximum principle theorem. Besides, we demonstrate the solution
exists for all time and converges pointwisely to a hyperbolic metric


title: BPS counting for knots and combinatorics on words

abstract:
  We discuss relations between quantum BPS invariants defined in terms of a
product decomposition of certain series, and difference equations (quantum
A-polynomials) that annihilate such series. We construct combinatorial models
whose structure is encoded in the form of such difference equations, and whose
generating functions (Hilbert-Poincar\'e series) are solutions to those
equations and reproduce generating series that encode BPS invariants.
Furthermore, BPS invariants in question are expressed in terms of Lyndon words
in an appropriate language, thereby relating counting of BPS states to the
branch of mathematics referred to as combinatorics on words. We illustrate
these results in the framework of colored extremal knot polynomials: among
others we determine dual quantum extremal A-polynomials for various knots,
present associated combinatorial models, find corresponding BPS invariants
(extremal Labastida-Mari\~no-Ooguri-Vafa invariants) and discuss their
integrality.


title: An explanation of trans-ionospheric pulse pairs

abstract:
  Trans-ionospheric pulse pairs are the most powerful natural radio signals on
the Earth and associated with lightning. They have been discovered for two
decades by satellites, but their origin still remains elusive. Here we
attribute these radio signals to relativistic electrons produced by
cloud-to-ground lightning. When these electrons strike the ground, radio bursts
are emitted towards space in a narrow cone. This model naturally explains the
interval, duration, polarization, coherence and bimodal feature of the pulse
pairs. Based on electron parameters inferred from x-ray observation of
lightning, the calculated signal intensity agrees with the measurement of
satellites. Our results are useful to develop global warning system of storms
and hurricane based on GPS satellites.

categories: physics.plasm-ph physics.ao-ph physics.geo-ph physics.space-ph


title: Self-Averaging Expectation Propagation

abstract:
  We investigate the problem of approximate Bayesian inference for a general
class of observation models by means of the expectation propagation (EP)
framework for large systems under some statistical assumptions. Our approach
tries to overcome the numerical bottleneck of EP caused by the inversion of
large matrices. Assuming that the measurement matrices are realizations of
specific types of ensembles we use the concept of freeness from random matrix
theory to show that the EP cavity variances exhibit an asymptotic
self-averaging property. They can be pre-computed using specific generating
functions, i.e. the R- and/or S-transforms in free probability, which do not
require matrix inversions. Our approach extends the framework of (generalized)
approximate message passing -- assumes zero-mean iid entries of the measurement
matrix -- to a general class of random matrix ensembles. The generalization is
via a simple formulation of the R- and/or S-transforms of the limiting
eigenvalue distribution of the Gramian of the measurement matrix. We
demonstrate the performance of our approach on a signal recovery problem of
nonlinear compressed sensing and compare it with that of EP.


title: Arbitrary optical wavefront shaping via spin-to-orbit coupling

abstract:
  Converting spin angular momentum to orbital angular momentum has been shown
to be a practical and efficient method for generating optical beams carrying
orbital angular momentum and possessing a space-varying polarized field. Here,
we present novel liquid crystal devices for tailoring the wavefront of optical
beams through the Pancharatnam-Berry phase concept. We demonstrate the
versatility of these devices by generating an extensive range of optical beams
such as beams carrying $\pm200$ units of orbital angular momentum along with
Bessel, Airy and Ince-Gauss beams. We characterize both the phase and the
polarization properties of the generated beams, confirming our devices'
performance.


title: On the location of maximal of solutions of Schr\"odinger's equation

abstract:
  We prove an inequality with applications to solutions of the Schr\"odinger
equation. There is a universal constant $c>0$, such that if $\Omega \subset
\mathbb{R}^2$ is simply connected, $u:\Omega \rightarrow \mathbb{R}$ vanishes
on the boundary $\partial \Omega$, and $|u|$ assumes a maximum in $x_0 \in
\Omega$, then $$ \inf_{y \in \partial \Omega}{ \| x_0 - y\|} \geq c \left\|
\frac{\Delta u}{u} \right\|^{-1/2}_{L^{\infty}(\Omega)}.$$ It was conjectured
by P\'olya \& Szeg\H{o} (and proven, independently, by Makai and Hayman) that a
membrane vibrating at frequency $\lambda$ contains a disk of size $\sim
\lambda^{-1/2}$. Our inequality implies a refined result: the point on the
membrane that achieves the maximal amplitude is at distance $\sim
\lambda^{-1/2}$ from the boundary. We also give an extension to higher
dimensions (generalizing results of Lieb and Georgiev \& Mukherjee): if $u$
solves $-\Delta u = Vu$ on $\Omega \subset \mathbb{R}^n$ with Dirichlet
boundary conditions, then the ball $B$ with radius $\sim
\|V\|_{L^{\infty}(\Omega)}^{-1/2}$ centered at the point in which $|u|$ assumes
a maximum is almost fully contained in $\Omega$ in the sense that $|B \cap
\Omega| \geq 0.99 |B|.$


title:
On the Odd Primary Homology of Free Algebras over the Spectral Lie
  Operad

abstract:
  The derivatives of the identity functor on spaces in Goodwillie calculus
forms an operad in spectra. Antolin-Camarena computed the mod 2 homology of
free algebras over this operad for 1-connected spectra. In this present paper
we carry out similar computations for mod p homology for odd primes p.


title: Mobile and Residential INEA Wi-Fi Hotspot Network

abstract:
  Since 2012 INEA has been developing and expanding the network of IEEE 802.11
compliant Wi-Fi hotspots (access points) located across the Greater Poland
region. This network consists of 330 mobile (vehicular) access points carried
by public buses and trams and over 20,000 fixed residential hotspots
distributed throughout the homes of INEA customers to provide Internet access
via the "community Wi-Fi" service. Therefore, this paper is aimed at sharing
the insights gathered by INEA throughout 4 years of experience in providing
hotspot-based Internet access. The emphasis is put on daily and hourly trends
in order to evaluate user experience, to determine key patterns, and to
investigate the influences such as public transportation trends, user location
and mobility, as well as, radio frequency noise and interference.


title: Coupling ideality of integrated planar high-Q microresonators

abstract:
  Chipscale microresonators with integrated planar optical waveguides are
useful building blocks for linear, nonlinear and quantum optical devices. Loss
reduction through improving fabrication processes has resulted in several
integrated micro resonator platforms attaining quality (Q) factors of several
millions. However only few studies have investigated design-dependent losses,
especially with regard to the resonator coupling section. Here we investigate
design-dependent parasitic losses, described by the coupling ideality, of the
commonly employed microresonator design consisting of a microring resonator
waveguide side-coupled to a straight bus waveguide. By systematic
characterization of multi-mode high-Q silicon nitride microresonator devices,
we show that this design can suffer from low coupling ideality. By performing
full 3D simulations to numerically investigate the resonator to bus waveguide
coupling, we identify the coupling to higher-order bus waveguide modes as the
dominant origin of parasitic losses which lead to the low coupling ideality.
Using suitably designed bus waveguides, parasitic losses are mitigated, and a
nearly unity ideality and strong overcoupling (i.e. a ratio of external
coupling to internal resonator loss rate > 9) are demonstrated. Moreover we
find that different resonator modes can exchange power through the coupler,
which therefore constitutes a mechanism that induces modal coupling, a
phenomenon known to distort resonator dispersion properties. Our results
demonstrate the potential for significant performance improvements of
integrated planar microresonators, achievable by optimized coupler designs.


title: Infinite-Label Learning with Semantic Output Codes

abstract:
  We develop a new statistical machine learning paradigm, named infinite-label
learning, to annotate a data point with more than one relevant labels from a
candidate set, which pools both the finite labels observed at training and a
potentially infinite number of previously unseen labels. The infinite-label
learning fundamentally expands the scope of conventional multi-label learning,
and better models the practical requirements in various real-world
applications, such as image tagging, ads-query association, and article
categorization. However, how can we learn a labeling function that is capable
of assigning to a data point the labels omitted from the training set? To
answer the question, we seek some clues from the recent work on zero-shot
learning, where the key is to represent a class/label by a vector of semantic
codes, as opposed to treating them as atomic labels. We validate the
infinite-label learning by a PAC bound in theory and some empirical studies on
both synthetic and real data.


title: On the Spectral Gap of Spherical Spin Glass Dynamics

abstract:
  We consider the time to equilibrium for the Langevin dynamics of the
spherical $p$-spin glass model of system size $N$. We show that the log-Sobolev
constant and spectral gap are order $1$ in $N$ at sufficiently high temperature
whereas the spectral gap decays exponentially in $N$ at sufficiently low
temperatures. These verify the existence of a dynamical high temperature phase
and a dynamical glass phase at the level of the spectral gap. Key to these
results are the understanding of the extremal process and restricted free
energy of Subag--Zeitouni and Subag.


title:
Challenges in flow background removal in search for the chiral magnetic
  effect

abstract:
  We investigate the effect of resonance decays on the three-particle
correlator charge separation observable in search for the chiral magnetic
effect, using a simple simulation with realistic inputs. We find that resonance
decays can largely account for the measured signal. We suppress the elliptic
flow ($v_2$) background by using zero event-by-event $v_2$ (or via the
mixed-event technique). We find that the background is suppressed, but not
eliminated as naively anticipated. We identify the reason to be the
non-identicalness of the resonance and final-state particle's $v_2$ and the
induced correlation between the transverse momentum dependent resonance $v_2$
and decay angle. We make predictions for the charge separation signal due to
resonance decays in 200~GeV Au+Au collisions.


title:
Fundamental group of finite von Neumann algebras with finite dimensional
  normal trace space

abstract:
  We introduce the fundamental group $F(\mathcal{M})$ of a finite von Neumann
algebra $\mathcal{M}$ with finite dimensional normal trace space. The form of
$F(\mathcal{M})$ is completely determined. Moreover, there exists a finite von
Neumann algebra $\mathcal{M}$ with finite dimensional normal trace space such
that $F(\mathcal{M})=G$ for any conceivable groups $G$ as fundamental group.


title: Restricting cohomology classes to disk and segment configuration spaces

abstract:
  The configuration space of n labeled disks of radius r inside the unit disk
is denoted Conf_{n, r}(D^2). We study how the cohomology of this space depends
on r. In particular, given a cohomology class of Conf_{n, 0}(D^2), for which r
does its restriction to Conf_{n, r}(D^2) vanish? A related question: given the
configuration space Seg_{n, r}(D^2) of n labeled, oriented segments of length
r, it has a map to (S^1)^n that records the direction of each segment. For
which r does this angle map have a continuous section? The paper consists of a
collection of partial results, and it contains many questions and conjectures.


title:
Diagonality Measures of Hermitian Positive-Definite Matrices with
  Application to the Approximate Joint Diagonalization Problem

abstract:
  In this paper, we introduce properly-invariant diagonality measures of
Hermitian positive-definite matrices. These diagonality measures are defined as
distances or divergences between a given positive-definite matrix and its
diagonal part. We then give closed-form expressions of these diagonality
measures and discuss their invariance properties. The diagonality measure based
on the log-determinant $\alpha$-divergence is general enough as it includes a
diagonality criterion used by the signal processing community as a special
case. These diagonality measures are then used to formulate minimization
problems for finding the approximate joint diagonalizer of a given set of
Hermitian positive-definite matrices. Numerical computations based on a
modified Newton method are presented and commented.


title:
A fast amortized algorithm for computing quadratic Dirichlet
  $L$-functions

abstract:
  An algorithm to compute Dirichlet $L$-functions for many quadratic characters
is derived. The algorithm is optimal (up to logarithmic factors) provided that
the conductors of the characters under consideration span a dyadic window.


title:
Comparison of the real and the complex Green functions, and sharp
  estimates of the Kobayashi distance

abstract:
  We extend the upper estimates obtained by M. Carlehed and B.-Y. Chen about
the ratio of the classical and pluricomplex Green functions to the case of
$\mathcal C^2$-smooth locally $\mathbb C$-convexifiable domains of finite type.
We also give some lower estimates. In order to obtain those results, and
because it is of independent interest, we refine and unify some classical
estimates about the Kobayashi distance and the Lempert function in such
domains.


title: Dipolar condensates with tilted dipoles in a pancake-shaped confinement

abstract:
  The effect of dipolar orientation with respect to the condensate plane on the
mean-field dynamics of dipolar Bose-Einstein condensates in a pancake-shaped
confinement is discussed. The stability of a quasi-two-dimensional condensate,
with respect to the tilting angle, is found to be different from a
two-dimensional layer of dipoles, indicating the relevance of the transverse
extension while characterizing two-dimensional dipolar systems. An anisotropic
excitation spectrum exhibiting a highly tunable, rotonlike minimum can arise
entirely from the dipole-dipole interactions, by tilting the dipoles. At the
magic angle and in the absence of contact interactions, the long-wavelength
excitations are not phononlike and always unstable. The post-roton-instability
dynamics, in contrast to phonon instability, in a uniform condensate, is
featured by a transient, defect-free, stripe pattern, which eventually
undergoes local collapses, and driving the condensate back into the stable
regime can make them sustained for longer. Hopping between stripes has been
observed before it melts into a uniform state in the presence of dissipation.
Finally, we discuss a class of solutions, in which a quasi-two-dimensional
condensate is self-trapped in one direction, as well as a regime of interaction
parameters, including attractive short-range interactions, at which a
two-dimensional anisotropic soliton can be stabilized, and we show that a
chromium condensate with a relatively small number of atoms is well suited for
this.


title: Quantum Communication Complexity of Distributed Set Joins

abstract:
  Computing set joins of two inputs is a common task in database theory.
Recently, Van Gucht, Williams, Woodruff and Zhang [PODS 2015] considered the
complexity of such problems in the natural model of (classical) two-party
communication complexity and obtained tight bounds for the complexity of
several important distributed set joins.
  In this paper we initiate the study of the *quantum* communication complexity
of distributed set joins. We design a quantum protocol for distributed Boolean
matrix multiplication, which corresponds to computing the composition join of
two databases, showing that the product of two $n\times n$ Boolean matrices,
each owned by one of two respective parties, can be computed with
$\widetilde{O}(\sqrt{n}\ell^{3/4})$ qubits of communication, where $\ell$
denotes the number of non-zero entries of the product. Since Van Gucht et al.
showed that the classical communication complexity of this problem is
$\widetilde{\Theta}(n\sqrt{\ell})$, our quantum algorithm outperforms classical
protocols whenever the output matrix is sparse. We also show a quantum lower
bound and a matching classical upper bound on the communication complexity of
distributed matrix multiplication over $\mathbb{F}_2$.
  Besides their applications to database theory, the communication complexity
of set joins is interesting due to its connections to direct product theorems
in communication complexity. In this work we also introduce a notion of
*all-pairs* product theorem, and relate this notion to standard direct product
theorems in communication complexity.


title:
Nambu-Goldstone Boson Hypothesis for Squarks and Sleptons in Pure
  Gravity Mediation

abstract:
  We point out that a hypothesis of squarks and sleptons being Nambu-Goldstone
(NG) bosons is consistent with pure gravity mediation or minimal split
supersymmetry (SUSY). As a concrete example, we consider a SUSY $E_7/SU(5)
\times U(1)^3$ non-linear sigma model in the framework of pure gravity
mediation. The model accommodates three families of the quark and lepton chiral
multiplets as (pseudo) NG multiplets of the Kahler manifold, which may enable
us to understand the origin and number of the families. We point out that
squarks in the first and second generations are likely to be as light as a few
TeV if the observed baryon asymmetry is explained by the thermal leptogenesis;
therefore, these colored particles can be discovered at the LHC Run-2 or at the
high luminosity LHC.


title:
Probing the Electroweak Phase Transition with Higgs Factories and
  Gravitational Waves

abstract:
  After the discovery of the Higgs boson, understanding the nature of
electroweak symmetry breaking and the associated electroweak phase transition
has become the most pressing question in particle physics. Answering this
question is a priority for experimental studies. Data from the LHC and future
lepton collider-based Higgs factories may uncover new physics coupled to the
Higgs boson, which can induce the electroweak phase transition to become first
order. Such a phase transition generates a stochastic background of
gravitational waves, which could potentially be detected by a space-based
gravitational wave interferometer. In this paper, we survey a few classes of
models in which the electroweak phase transition is strongly first order. We
identify the observables that would provide evidence of these models at the LHC
and next-generation lepton colliders, and we assess whether the corresponding
gravitational wave signal could be detected by eLISA. We find that most of the
models with first order electroweak phase transition can be covered by the
precise measurements of Higgs couplings at the proposed Higgs factories. We
also map out the model space that can be probed with gravitational wave
detection by eLISA.


title: Measurement of $CP$ violation in $B^0 \!\rightarrow D^+ D^-$ decays

abstract:
  The $CP$ violation observables $S$ and $C$ in the decay channel $B^0
\!\rightarrow D^+ D^-$ are determined from a sample of proton-proton collisions
at center-of-mass energies of 7 and 8 TeV, collected by the LHCb experiment and
corresponding to an integrated luminosity of 3 fb$^{-1}$. The observable $S$
describes $CP$ violation in the interference between mixing and the decay
amplitude, and $C$ parametrizes direct $CP$ violation in the decay. The
following values are obtained from a flavor-tagged, decay-time-dependent
analysis: \begin{align*}
  S &= -0.54 \, ^{+0.17}_{-0.16} \, \text{(stat)} \pm 0.05 \,
\text{(syst)}\,,\newline
  C &= \phantom{-}0.26 \, ^{+0.18}_{-0.17} \, \text{(stat)} \pm 0.02 \,
\text{(syst)}\,. \end{align*} These values provide evidence for $CP$ violation
at a significance level of 4.0 standard deviations. The phase shift due to
higher-order Standard Model corrections is constrained to a small value of
\begin{align*}
  \Delta\phi = -0.16\,^{+0.19}_{-0.21}\,\text{rad}\,. \end{align*}


title: The Minimum Number of Edges in Uniform Hypergraphs with Property O

abstract:
  An oriented k-uniform hypergraph (a family of ordered k-sets) has the
ordering property (or Property O) if for every linear order of the vertex set,
there is some edge oriented consistently with the linear order. We find bounds
on the minimum number of edges in a hypergraph with Property O.


title:
The discriminative Kalman filter for nonlinear and non-Gaussian
  sequential Bayesian filtering

abstract:
  The Kalman filter (KF) is used in a variety of applications for computing the
posterior distribution of latent states in a state space model. The model
requires a linear relationship between states and observations. Extensions to
the Kalman filter have been proposed that incorporate linear approximations to
nonlinear models, such as the extended Kalman filter (EKF) and the unscented
Kalman filter (UKF). However, we argue that in cases where the dimensionality
of observed variables greatly exceeds the dimensionality of state variables, a
model for $p(\text{state}|\text{observation})$ proves both easier to learn and
more accurate for latent space estimation. We derive and validate what we call
the discriminative Kalman filter (DKF): a closed-form discriminative version of
Bayesian filtering that readily incorporates off-the-shelf discriminative
learning techniques. Further, we demonstrate that given mild assumptions,
highly non-linear models for $p(\text{state}|\text{observation})$ can be
specified. We motivate and validate on synthetic datasets and in neural
decoding from non-human primates, showing substantial increases in decoding
performance versus the standard Kalman filter.


title:
Near-Field studies of anisotropic variations and temperature induced
  structural changes in a supported single lipid bilayer

abstract:
  Temperature controlled Polarization Modulation Near-Field Scanning Optical
Microscopy (PM-NSOM) measurements of a single supported $L_{\beta^{\prime}}$
1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipid bilayer are presented.
The effective retardance ($\Delta S = \frac{2 \pi (n_e-n_o)t}{\lambda}$), where
$t$ is the thickness of the bilayer and $\lambda$ is the wavelength of light
used and the direction of the projection of the acyl chains ($\theta $) were
measured simultaneously. From $\Delta S$ the birefringence ($n_e-n_o$) of the
bilayer was determined. A change of $\Delta S$ $\sim$ (3.8 $\pm$ 0.3)~mrad at
the transition temperature $T_m \sim$ 41$^{\circ}$C between the gel
$L_{\beta^{\prime}}$ to liquid disorder $L_{\alpha}$ was observed in a single
planar bilayer. This agrees well with previous values of ($n_e-n_o$) in the
$L_{\beta^{\prime}}$ phase and translates to an assumed $\langle \phi \rangle $
$\sim$ 32$^{\circ}$ when T $<T_m$ and 0$^{\circ}$ when T $>T_m$. Evidence of
supper heating and supper cooling are presented, along with a discussion of the
behavior that occurs around $T_m$.


title: Mellin amplitudes for $AdS_5\times S^5$

abstract:
  We revisit the calculation of holographic correlation functions in IIB
supergravity on $AdS_5\times S^5$. Results for four-point functions simplify
drastically when expressed in Mellin space. We conjecture a compact formula for
the four-point functions of one-half BPS single-trace operators of arbitrary
weight. Our methods rely on general consistency conditions and eschew detailed
knowledge of the supergravity effective action.


title:
Chiral anomaly and longitudinal magnetotransport in type-II Weyl
  semimetals

abstract:
  In the presence of parallel electric and magnetic fields, the violation of
separate number conservation laws for the three dimensional left and right
handed Weyl fermions is known as the chiral anomaly. The recent discovery of
Weyl and Dirac semimetals has paved the way for experimentally testing the
effects of chiral anomaly via longitudinal magneto-transport measurements. More
recently, a type-II Weyl semimetal (WSM) phase has been proposed, where the
nodal points possess a finite density of states due to the touching between
electron- and hole- pockets. It has been suggested that the main difference
between the two types of WSMs (type-I and type-II) is that in the latter,
chiral anomaly and the associated longitudinal magneto-resistance are strongly
anisotropic, vanishing when the applied magnetic field is perpendicular to the
direction of tilt of Weyl fermion cones in a type-II WSM. We analyze chiral
anomaly in a type-II WSM in quasiclassical Boltzmann framework, and find that
the chiral anomaly induced positive longitudinal magneto-conductivity is
present along any arbitrary direction.


title:
Galaxy Secular Mass Flow Rate Determination Using the Potential-Density
  Phase Shift Approach: Application to Six Nearby Spiral Galaxies

abstract:
  Using the potential-density phase shift approach developed by the present
authors in earlier publications, we estimate the magnitude of radial mass
accretion/excretion rates across the disks of six nearby spiral galaxies having
a range of Hubble types. Our goal is to examine these rates in the context of
bulge building and secular morphological evolution along the Hubble sequence.
Stellar surface density maps of the sample galaxies are derived from SINGS
3.6um and SDSS i-band images. Corresponding molecular and atomic gas surface
densities are derived from published CO(1-0) and HI interferometric
observations of the BIMA SONG, THINGS, and VIVA surveys. The mass flow rate
calculations utilize a volume-type torque integral to calculate the angular
momentum exchange rate between the basic state disk matter and density wave
modes. The potential-density phase shift approach yields angular momentum
transport rates several times higher than those estimated using the Lynden-Bell
and Kalnajs (1972) approach. The current approach leads to predictions of
significant mass redistribution induced by the quasi-steady density wave modes,
enough for the morphological types of disks to evolve substantially within its
lifetime. This difference with the earlier conclusions of Lynden-Bell and
Kalnajs reflects the dominant role played by collisionless shocks in the
secular evolution of galaxies containing extremely non-linear, quasi-steady
density wave modes, thus enabling significant morphological transformation
along the Hubble sequence during a Hubble time. We show for the first time
also, using observational data, that STELLAR mass accretion/excretion is just
as important, and oftentimes much more important, than the corresponding
accretion/excretion processes in the GASEOUS component, with the latter being
what had been emphasized in most of the previous secular evolution studies.


title: Artificial Neural Networks for Detection of Malaria in RBCs

abstract:
  Malaria is one of the most common diseases caused by mosquitoes and is a
great public health problem worldwide. Currently, for malaria diagnosis the
standard technique is microscopic examination of a stained blood film. We
propose use of Artificial Neural Networks (ANN) for the diagnosis of the
disease in the red blood cell. For this purpose features / parameters are
computed from the data obtained by the digital holographic images of the blood
cells and is given as input to ANN which classifies the cell as the infected
one or otherwise.


title: On the mechanism of hydrophilicity of graphene

abstract:
  It is generally accepted that the hydrophilic property of graphene can be
affected by the underlying substrate. However, the role of intrinsic vs.
substrate contributions and the related mechanisms are vividly debated. Here we
show that the intrinsic hydrophilicity of graphene can be intimately connected
to the position of its Fermi level, which affects the interaction between
graphene and water molecules. The underlying substrate, or dopants, can tune
hydrophilicity by modulating the Fermi level of graphene. By shifting the Fermi
level of graphene away from its Dirac point, via either chemical or electrical
voltage doping, we show enhanced hydrophilicity with experiments and first
principle simulations. Increased vapor condensation on graphene, induced by a
simple shifting of its Fermi level, exemplifies applications in the area of
interfacial transport phenomena.


title:
Resonant Response in Mechanically Tunable Metasurface based on Crossed
  Metallic Gratings with Controllable Crossing Angle

abstract:
  We report on a new class of mechanically tunable planar metamaterials
comprising resonating units formed by crossed metallic strip gratings. We
observe a resonant response in transmission spectra of a linearly polarized
wave passing through the system of crossed gratings. Each grating consists of
an array of parallel metallic strips located on the top of a dielectric
substrate. It is revealed that the resonant position appears to be dependent on
the angle of gratings crossing. It is found out both theoretically and
experimentally that the resonant shift on the frequency scale appears as a
result of increasing in the length of the resonating portion of the
parallelogram periodic cell formed by the crossed metallic strips with
decreasing crossing angle and the proposed design can be used in new types of
planar metamaterials and filters.


title: Unitary subgroups and orbits of compact self-adjoint operators

abstract:
  Let H be a separable Hilbert space, and D(B(H))^ah the anti-Hermitian bounded
diagonals in some fixed orthonormal basis and K(H) the compact operators. We
study the group of unitary operators
  U_kd = {u in U(H): such that u-e^D in K(H) for D in D(B(H))^ah}
  in order to obtain a concrete description of short curves in unitary Fredholm
orbits Ob={ e^K b e^{-K} : K in K(H)^ah } of a compact self-adjoint operator b
with spectral multiplicity one. We consider the rectifiable distance on Ob
defined as the infimum of curve lengths measured with the Finsler metric
defined by means of the quotient space K(H)^ah / D(K(H)^ah). Then for every c
in Ob and x in T(\ob)_c there exist a minimal lifting Z_0 in B(H)^ah (in the
quotient norm, not necessarily compact) such that g(t)=e^{t Z_0} c e^{-t Z_0}
is a short curve on Ob in a certain interval.


title: Three-dimensional topological solitons in PT-symmetric optical lattices

abstract:
  We address the properties of fully three-dimensional solitons in complex
parity-time (PT)-symmetric periodic lattices with focusing Kerr nonlinearity,
and uncover that such lattices can stabilize both, fundamental and
vortex-carrying soliton states. The imaginary part of the lattice induces
internal currents in the solitons that strongly affect their domains of
existence and stability. The domain of stability for fundamental solitons can
extend nearly up to the PT-symmetry breaking point, where the linear lattice
spectrum becomes complex. Vortex solitons feature spatially asymmetric profiles
in the PT-symmetric lattices, but they are found to still exist as stable
states within narrow regions. Our results provide the first example of
continuous families of stable three-dimensional propagating solitons supported
by complex potentials.


title:
Weyl fermions with arbitrary monopole in magnetic fields: Landau levels,
  longitudinal magnetotransport, and density-wave ordering

abstract:
  We theoretically address the effects of strong magnetic fields in
three-dimensional Weyl semimetals (WSMs) built out of Weyl nodes with a
monopole charge $n$. For $n=1$, $2$, and $3$ we realize single, double, and
triple WSM, respectively, and the monopole charge $n$ determines the integer
topological invariant of the WSM. Within the linearized continuum description,
the quasiparticle spectrum is then composed of Landau levels (LLs), containing
exactly $n$ number of chiral zeroth Landau levels (ZLLs), irrespective of the
orientation of the magnetic field. In the presence of strong backscattering,
for example, (due to quenched disorder associated with random impurities),
these systems generically give rise to longitudinal magnetotransport.
Restricting ourselves to the quantum limit (and assuming only the subspace of
the ZLLs to be partially filled) and mainly accounting for Gaussian impurities,
we show that the longitudinal magnetoconductivity (LMC) in all members of the
Weyl family displays a positive linear-$B$ scaling, when the field is applied
along the axis that separates the Weyl nodes. But, in double and triple WSM,
LMC displays a smooth crossover to a nonlinear $B$-dependence as the field is
tilted away from such a high-symmetry direction. In addition, due to the
enhanced density of states, the LL quantization can trigger instabilities
toward the formation of translational symmetry breaking density-wave orderings
for sufficiently weak interaction (BCS instability), which gaps out the ZLLs.
Concomitantly as the temperature (magnetic field) is gradually decreased
(increased) the LMC becomes negative. Thus WSMs with arbitrary monopole charge
($n$) can host an intriguing interplay of LL quantization, longitudinal
magnetotransport (a possible manifestation of one-dimensional chiral or axial
anomaly), and density-wave ordering, when placed in a strong magnetic field.


title:
Disorder effect on the anisotropic resistivity of phosphorene determined
  by a tight-binding model

abstract:
  In this work we develop a compact multi-orbital tight-binding model for
phosphorene that accurately describes states near the main band gap. The model
parameters are adjusted using as reference the band structure obtained by a
density-functional theory calculation with the hybrid HSE06 functional. We use
the optimized tight-binding model to study the effects of disorder on the
anisotropic transport properties of phosphorene. In particular, we evaluate how
the longitudinal resistivity depends on the lattice orientation for two typical
disorder models: dilute scatterers with high potential fluctuation amplitudes,
mimicking screened charges in the substrate, and dense scatterers with lower
amplitudes, simulating weakly bounded adsorbates. We show that the intrinsic
anisotropy associated to the band structure of this material, although
sensitive to the type and intensity of the disorder, is robust.


title: Disorder effects in correlated topological insulators

abstract:
  Using exact diagonalization and quantum Monte Carlo calculations we
investigate the effects of disorder on the phase diagram of both
non-interacting and interacting models of two-dimensional topological
insulators. In the fermion sign problem-free interacting models we study,
electron-electron interactions are described by an on-site repulsive Hubbard
interaction and disorder is included via the one-body hopping operators. In
both the non-interacting and interacting models we make use of recent advances
in highly accurate real-space numerical evaluation of topological invariants to
compute phase boundaries, and in the non-interacting models determine critical
exponents of the transitions. We find different models exhibit distinct
stability conditions of the topological phase with respect to interactions and
disorder. We provide a general analytical theory that accurately predicts these
trends.


title: Kinetic Mixing at Strong Coupling

abstract:
  A common feature of many string-motivated particle physics models is
additional strongly coupled U(1)'s. In such sectors, electric and magnetic
states have comparable mass, and integrating out modes also charged under U(1)
hypercharge generically yields CP preserving electric kinetic mixing and CP
violating magnetic kinetic mixing terms. Even though these extra sectors are
strongly coupled, we show that in the limit where the extra sector has
approximate N = 2 supersymmetry, we can use formal methods from Seiberg-Witten
theory to compute these couplings. We also calculate various quantities of
phenomenological interest such as the cross section for scattering between
visible sector states and heavy extra sector states, as well as the effects of
supersymmetry breaking induced from coupling to the MSSM.


title:
Realistic many-body quantum systems vs full random matrices: static and
  dynamical properties

abstract:
  We study the static and dynamical properties of isolated many-body quantum
systems and compare them with the results for full random matrices. In doing
so, we link concepts from quantum information theory with those from quantum
chaos. In particular, we relate the von Neumann entanglement entropy with the
Shannon information entropy and discuss their relevance for the analysis of the
degree of complexity of the eigenstates, the behavior of the system at
different time scales and the conditions for thermalization. A main advantage
of full random matrices is that they enable the derivation of analytical
expressions that agree extremely well with the numerics and provide bounds for
realistic many-body quantum systems.


title:
Realizing infrared power-law liquids in the cuprates from unparticle
  interactions

abstract:
  Recent photoemission experiments \cite{dessau} reveal that the excitations
along the nodal region in the strange metal of the cuprates, rather than
corresponding to poles in the single-particle Green function, exhibit power-law
scaling as a function of frequency and temperature. Because such power-law
scaling is indicative of a scale-invariant sector, as a first step, we
perturbatively evaluate the electron self-energy due to interactions with
scale-invariant unparticles. We focus on a $G_0W$ type diagram with an
interaction $W$ mediated by a bosonic scalar unparticle. We find that, in the
high-temperature limit, the imaginary part of the self-energy
$\mathrm{Im}\Sigma$ is linear in temperature. In the low-temperature limit,
$\mathrm{Im}\Sigma$ exhibits the same power law in both temperature and
frequency, with an exponent that depends on the scaling dimension of an
unparticle operator. Such behavior is qualitatively consistent with the
experimental observations. We then expand the unparticle propagator into
coherent and incoherent contributions, and study how the incoherent part
violates the density of states (DOS) and density-density correlation function
sum rules (f-sum rule). Such violations can, in principle, be observed
experimentally. Our work indicates that the physical mechanism for the origin
of the power-law scaling is the incoherent background, which is generated from
the Mott-scale physics.


title: RG Flows and Bifurcations

abstract:
  Interpreting RG flows as dynamical systems in the space of couplings we
produce a variety of constraints, global (topological) as well as local. These
constraints, in turn, rule out some of the proposed RG flows and also predict
new phases and fixed points, surprisingly, even in familiar theories such as
O(N) model, QED-3, or QCD-4.


title:
Entanglement of Exact Excited Eigenstates of the Hubbard Model in
  Arbitrary Dimension

abstract:
  We compute exactly the von Neumann entanglement entropy of the eta-pairing
states - a large set of exact excited eigenstates of the Hubbard Hamiltonian.
For the singlet eta-pairing states the entropy scales with the logarithm of the
spatial dimension of the (smaller) partition. For the eta-pairing states with
finite spin magnetization density, the leading term can scale as the volume or
as the area-times-log, depending on the momentum space occupation of the
Fermions with flipped spins. We also compute the corrections to the leading
scaling. In order to study the eigenstate thermalization hypothesis (ETH), we
also compute the entanglement Renyi entropies of such states and compare them
with the corresponding entropies of thermal density matrix in various
ensembles. Such states, which we find violate strong ETH, may provide a useful
platform for a detailed study of the time-dependence of the onset of
thermalization due to perturbations which violate the total pseudospin
conservation.


title: Mott transition and magnetism on the anisotropic triangular lattice

abstract:
  Spin-liquid behavior was recently suggested experimentally in the moderately
one-dimensional organic compound $\kappa$-H$_3$(Cat-EDT-TTF)$_2$. This compound
can be modeled by the one-band Hubbard model on the anisotropic triangular
lattice with $t^\prime/t \simeq 1.5$, where $t'$ is the minority hopping. It
thus becomes important to extend previous studies, that were performed in the
range $0 \leq t'/t \leq 1.2$, to find out whether there is a regime where Mott
insulating behavior can be found without long-range magnetic order. To this
end, we study the above model in the range $1.2 \leq t'/t \leq 2$ using cluster
dynamical mean-field theory (CDMFT). We argue that it is important to choose a
symmetry-preserving cluster rather than a quasi one-dimensional cluster. We
find that, upon increasing $t'/t$ beyond $t^\prime/t \approx 1.3$, the Mott
transition at zero-temperature is replaced by a first-order transition
separating a metallic state from a collinear magnetic insulating state.
Nevertheless, at the physically relevant value $t^\prime/t \simeq 1.5$, the
transitions toward the magnetic and the Mott insulating phases are very close.
The phase diagram obtained in this study can provide a working basis for
moderately one-dimensional compounds on the anisotropic triangular lattice.


title: Generalized $\lambda$-deformations of AdS_p x S^p

abstract:
  We study analytical properties of the generalized $\lambda$-deformation,
which modifies string theories while preserving integrability, and construct
the explicit backgrounds corresponding to AdS_p x S^p, including the
Ramond-Ramond fluxes. For an arbitrary coset, we find the general form of the
R-matrix underlying the deformation, and prove that the dilaton is not modified
by the deformation, while the frames are multiplied by a constant matrix. Our
explicit solutions describe families of integrable string theories depending on
several continuous parameters.


title:
UV/IR Mixing In Non-Fermi Liquids: Higher-Loop Corrections In Different
  Energy Ranges

abstract:
  We revisit the Ising-nematic quantum critical point with an $m$-dimensional
Fermi surface by applying a dimensional regularization scheme, introduced in
Phys. Rev. B 92, 035141 (2015). We compute the contribution from two-loop and
three-loop diagrams in the intermediate energy range controlled by a crossover
scale. We find that for $m=2 $, the corrections continue to be one-loop exact
for both the infrared and intermediate energy regimes.


title: On scale-free extensions of massive (bi-)gravity

abstract:
  We discuss a scale-free model of bigravity, in which the mass parameter of
the standard bigravity potential is promoted to a dynamical scalar field. This
modification retains the ghost-free bigravity structure, in particular it
remains free of the Boulware-Deser ghost. We investigate the theory's
interaction structure, focusing on its consistent scaling limits and strong
coupling scales. Furthermore we explore the model's quadratic action, both
around generic background configurations and paying special attention to
cosmological backgrounds and to the associated background evolution. Finally we
consider the possibility of realizing a phase of late-time acceleration as well
as a quasi-de Sitter inflationary stage at early times, when the promoted "mass
scalar" becomes the inflaton.


title: Uniformisation of higher-dimensional minimal varieties

abstract:
  After a historical discussion of classical uniformisation results for Riemann
surfaces, of problems appearing in higher dimensions, and of uniformisation
results for projective manifolds with trivial or ample canonical bundle, we
introduce the basic technical concepts and sketch the ideas of the proofs for
recent uniformisation theorems for singular varieties obtained by the authors
in collaboration with Thomas Peternell.


title:
FemtoDAQ: A Low-Cost Digitizer for SiPM-Based Detector Studies and its
  Application to the HAWC Detector Upgrade

abstract:
  The FemtoDAQ is a low-cost two channel data acquisition system which we have
used to investigate the signal characteristics of silicon photomultipliers
(SiPMs) coupled to fast scintillators. The FemtoDAQ system can also be used to
instrument low cost moderate performance passive detectors, and is suitable for
use in harsh environments (e.g., high altitude). The FemtoDAQ is being used as
a SiPM test bench for the High Altitude Water Cherenkov (HAWC) Observatory, a
TeV gamma ray detector located 4100 m above sea level. Planned upgrades to the
HAWC array can benefit greatly from SiPMs, a robust, low-voltage, low-cost
alternative to traditional vacuum photomultipliers. The FemtoDAQ is used to
power the SiPM detector front end, bias the SiPM, and digitize the photosensor
output in a single compact unit.


title: Forbidden subposet problems with size restrictions

abstract:
  Upper bounds to the size of a family of subsets of an n-element set that
avoids certain configurations are proved. These forbidden configurations can be
described by inclusion patterns and some sets having the same size. Our results
are closely related to the forbidden subposet problems, where the avoided
configurations are described solely by inclusions.


title: A Luminous Gamma-ray Binary in the Large Magellanic Cloud

abstract:
  Gamma-ray binaries consist of a neutron star or a black hole interacting with
a normal star to produce gamma-ray emission that dominates the radiative output
of the system. Only a handful of such systems have been previously discovered,
all within our Galaxy. Here we report the discovery with the Fermi Large Area
Telescope (LAT) of a luminous gamma-ray binary in the Large Magellanic Cloud
from a search for periodic modulation in all sources in the third Fermi LAT
catalog. This is the first such system to be found outside the Milky Way. The
system has an orbital period of 10.3 days and is associated with a massive
O5III star located in the supernova remnant DEM L241, previously identified as
the candidate high-mass X-ray binary (HMXB) CXOU J053600.0-673507. X-ray and
radio emission are also modulated on the 10.3 day period, but are in anti-phase
with the gamma-ray modulation. Optical radial velocity measurements suggest
that the system contains a neutron star. The source is significantly more
luminous than similar sources in the Milky Way at radio, optical, X-ray and
gamma-ray wavelengths. The detection of this extra-galactic system, but no new
Galactic systems raises the possibility that the predicted number of gamma-ray
binaries in our Galaxy has been overestimated, and that HMXBs may be born
containing relatively slowly rotating neutron stars.


title: Short-range Photoassociation of LiRb

abstract:
  We have observed short-range photoassociation of LiRb to the two lowest
vibrational states of the $d\,^3\Pi$ potential. These $d\,^3\Pi$ molecules then
spontaneously decay to vibrational levels of the $a^3\,\Sigma^+$ state with
generation rates of $\sim10^3$ molecules per second. This is the first
observation of many of these $a\,^3\Sigma^+$ levels. We observe an alternation
of the peak heights in the rotational photoassociation spectrum that suggests a
$p$-wave shape resonance in the scattering state. Franck-Condon overlap
calculations predict that photoassociation to higher vibrational levels of the
$d\,^3\Pi$, in particular the sixth vibrational level, should populate the
lowest vibrational level of the $a\,^3\Sigma^+$ state with a rate as high as
$10^4$ molecules per second. These results encourage further work to explain
our observed LiRb collisional physics using PECs. This work also motivates an
experimental search for short-range photoassociation to other bound molecules,
such as the $c\,^3\Sigma^+$ or $b\,^3\Pi$, as prospects for preparing
ground-state molecules.


title:
Expectation values of single-particle operators in the random phase
  approximation ground state

abstract:
  We developed a method for computing matrix elements of single-particle
operators in the correlated random phase approximation ground state. Working
with the explicit random phase approximation ground state wavefunction, we
derived practically useful and simple expression for a molecular property in
terms of random phase approximation amplitudes. The theory is illustrated by
the calculation of molecular dipole moments for a set of representative
molecules.


title:
Anisotropy-Induced Quantum Interference and Population Trapping Between
  Orthogonal Quantum Dot Exciton States in Semiconductor Cavity Systems

abstract:
  We describe how quantum dot semiconductor cavity systems can be engineered to
realize anisotropy-induced dipole-dipole coupling between orthogonal dipole
states in a single quantum dot. Quantum dots in single-mode cavity structures
as well as photonic crystal waveguides coupled to spin states or linearly
polarized excitons are considered. We demonstrate pronounced dipole-dipole
coupling to control the radiative decay rate of excitons and form pure
entangled states in the long time limit. We investigate both field-free
entanglement evolution and coherently pumped exciton regimes, and show how a
double pumping scenario can completely eliminate the decay of coherent Rabi
oscillations and lead to population trapping. In the Mollow regime, we explore
the emitted spectra from the driven dipoles and show how a non-pumped dipole
can take on the form of a spectral triplet, quintuplet, or a singlet, which has
applications for producing subnatural linewidth single photons and more easily
accessing regimes of high-field quantum optics and cavity-QED.


title: Unsupervised, Efficient and Semantic Expertise Retrieval

abstract:
  We introduce an unsupervised discriminative model for the task of retrieving
experts in online document collections. We exclusively employ textual evidence
and avoid explicit feature engineering by learning distributed word
representations in an unsupervised way. We compare our model to
state-of-the-art unsupervised statistical vector space and probabilistic
generative approaches. Our proposed log-linear model achieves the retrieval
performance levels of state-of-the-art document-centric methods with the low
inference cost of so-called profile-centric approaches. It yields a
statistically significant improved ranking over vector space and generative
models in most cases, matching the performance of supervised methods on various
benchmarks. That is, by using solely text we can do as well as methods that
work with external evidence and/or relevance feedback. A contrastive analysis
of rankings produced by discriminative and generative approaches shows that
they have complementary strengths due to the ability of the unsupervised
discriminative model to perform semantic matching.


title: Dynamics of simultaneously measured non-commuting observables

abstract:
  In quantum mechanics, measurements cause wavefunction collapse that yields
precise outcomes, for non-commuting observables such as position and momentum
Heisenberg's uncertainty principle limits the intrinsic precision of a state.
Although theoretical work has demonstrated the possibility to perform
simultaneous non-commuting measurements and has revealed the limits on
measurement outcomes, only recently has the dynamics of the quantum state been
discussed. To realize this unexplored regime, we simultaneously apply two
continuous quantum non-demolition probes of non-commuting observables to a
superconducting qubit. We implement multiple readout channels by coupling the
qubit to multiple modes of a cavity. To control the measurement observables, we
implement a 'single quadrature' measurement by driving the qubit and applying
cavity sidebands with a relative phase that sets the observable. Here, we show
that the uncertainty principle governs the dynamics of the wavefunction by
enforcing a lower bound on the measurement-induced disturbance. Consequently,
as we transition from measuring identical to measuring non-commuting
observables, the dynamics make a smooth transition from standard wavefunction
collapse to persistent diffusion. Although the evolution of the state differs
from that of a conventional measurement, information about both observables is
extracted by keeping track of the time ordering of the measurement record,
enabling quantum state tomography without alternating measurements. Our work
creates novel capabilities for quantum control, including rapid state
purification, adaptive measurement, measurement-based state steering and
continuous quantum error correction. As physical systems often interact
continuously with their environment via non-commuting degrees of freedom, our
work offers a way to study how notions of contemporary quantum foundations
arise in such settings.


title: A characteristic function approach to the Jaynes-Cummings model revivals

abstract:
  A two-level atom interacting with an electromagnetic mode in a cavity
experiences population collapses and revivals. They are an indirect signature
of the field quantization, and also hold information about the mode. Thus, they
may be harnessed for quantum-state reconstruction. In this work, we study the
revival structures with the characteristic function approach. The
characteristic function is essentially a spectral decomposition of the
photon-number probability distribution. Exploiting the characteristic function
periodicity, we find that the atomic population inversion can be understood as
the result of interference between a set of structures akin to a free
quantum-mechanical wave packet, each structure corresponding to snapshots of
this packet for different degrees of dispersion. When these structures do not
overlap, each of which can be identified to one of the inversion revivals, in
which case we may also retrieve the photon-number distribution.


title:
Stress-constrained continuum topology optimization: a new approach based
  on elasto-plasticity

abstract:
  A new approach for generating stress-constrained topological designs in
continua is presented. The main novelty is in the use of elasto-plastic
modeling and in optimizing the design such that it will exhibit a
linear-elastic response. This is achieved by imposing a single global
constraint on the total sum of equivalent plastic strains, providing accurate
control over all local stress violations. The single constraint essentially
replaces a large number of local stress constraints or an approximate
aggregation of them--two common approaches in the literature. A classical
rate-independent plasticity model is utilized, for which analytical adjoint
sensitivity analysis is derived and verified. Several examples demonstrate the
capability of the computational procedure to generate designs that challenge
results from the literature, in terms of the obtained stiffness-strength-weight
trade-offs. A full elasto-plastic analysis of the optimized designs shows that
prior to the initial yielding, these designs can sustain significantly higher
loads than minimum compliance topological layouts, with only a minor compromise
on stiffness.


title:
Wave formation process upon explosive welding: electron microscopic
  observations and imitating experiments

abstract:
  A sequence of the interface transition states was investigated. A transition
state has been found, during which cusps look like splashes. Images of the
splashes for different joints have been obtained. The processes of
self-organization of the splashes into a quasi-wave surface and a perfect wavy
surface have been revealed. Simulations experiments have been conducted.
Heterogeneity and the interface bending of one of the contacting materials have
been detected. They imitate the heterogeneity on the interface arising upon
explosive welding.


title: Lexical Query Modeling in Session Search

abstract:
  Lexical query modeling has been the leading paradigm for session search. In
this paper, we analyze TREC session query logs and compare the performance of
different lexical matching approaches for session search. Naive methods based
on term frequency weighing perform on par with specialized session models. In
addition, we investigate the viability of lexical query models in the setting
of session search. We give important insights into the potential and
limitations of lexical query modeling for session search and propose future
directions for the field of session search.


title: Affine invariant points and new constructions

abstract:
  In \cite{branko} Gr{\"u}nbaum asked if the set of all affine invariant points
of a given convex body is equal to the set of all points invariant under every
affine automorphism of the body. In \cite{ivan} we have proven the case of a
body with no nontrivial affine automorphisms. After some partial results
(\cite{aip},\cite{newaip}) the problem was solved in positive by Mordhorst
\cite{Olaf}. In this note we provide an alternative proof of the affirmative
answer, developing the ideas of \cite{ivan}. Moreover, our approach allows us
to construct a new large class of affine invariant points.


title:
Metric and classical fidelity uncertainty relations for random unitary
  matrices

abstract:
  We analyze uncertainty relations on finite dimensional Hilbert spaces
expressed in terms of classical fidelity, which are stronger then metric
uncertainty relations introduced by Fawzi, Hayden and Sen. We establish
validity of fidelity uncertainty relations for random unitary matrices with
optimal parameters (up to universal constants) which improves upon known
results for the weaker notion of metric uncertainty. This result is then
applied to locking classical information in quantum states and allows to obtain
optimal locking in Hellinger distance, improving upon previous results on
locking in the total variation distance, both by strengthening the metric used
and by improving the dependence on parameters. We also show that general
probabilistic estimates behind the main theorem can be used to prove existence
of data hiding schemes with Bayesian type guarantees. As a byproduct of our
approach we obtain existence of almost Euclidean subspaces of the matrix spaces
$\ell_1^n(\ell_2^m)$ with a better dimension/distortion dependence than allowed
in previously known constructions.

categories: quant-ph cs.IT math-ph math.IT math.MG math.MP math.PR