title: Dictionary Learning for Massive Matrix Factorization

abstract:
  Sparse matrix factorization is a popular tool to obtain interpretable data
decompositions, which are also effective to perform data completion or
denoising. Its applicability to large datasets has been addressed with online
and randomized methods, that reduce the complexity in one of the matrix
dimension, but not in both of them. In this paper, we tackle very large
matrices in both dimensions. We propose a new factoriza-tion method that scales
gracefully to terabyte-scale datasets, that could not be processed by previous
algorithms in a reasonable amount of time. We demonstrate the efficiency of our
approach on massive functional Magnetic Resonance Imaging (fMRI) data, and on
matrix completion problems for recommender systems, where we obtain significant
speed-ups compared to state-of-the art coordinate descent methods.


title:
Consequences of tidal interaction between disks and orbiting
  protoplanets for the evolution of multi-planet systems with architecture
  resembling that of Kepler 444

abstract:
  We study orbital evolution of multi-planet systems with masses in the
terrestrial planet regime induced through tidal interaction with a
protoplanetary disk assuming that this is the dominant mechanism for producing
orbital migration and circularization. We develop a simple analytic model for a
system that maintains consecutive pairs in resonance while undergoing orbital
circularization and migration. Migration times for each planet may be estimated
once planet masses, circularization times and the migration time for the
innermost planet are given. We applied it to a model system with the current
architecture of Kepler 444 interacting with a protoplanetary disk, the
evolution time for the system as a whole being comparable to current
protoplanetary disk lifetimes.
  In addition we performed numerical simulations with input data obtained from
this model. These indicate that although the analytic model is inexact,
relatively small corrections to estimated migration rates yield systems for
which period ratios vary by a minimal extent. Because of relatively large
deviations from exact resonance in the observed system of up to $2\%,$ the
migration times obtained in this way indicate only weak convergent migration
such that a system for which the planets did not interact would contract by
only $\sim 1\%$ although undergoing significant inward migration as a whole. We
performed additional simulations to investigate how the system could undergo
significant convergent migration before reaching its final state. These
indicate migration times have to be significantly shorter and resonances
significantly closer. Relative migration rates would then have to decrease
allowing period ratios to increase to become more distant from resonances as
the system approached its final state in the inner regions of the
protoplanetary disk (abridged).


title: Estimating discrete curvatures in terms of beta numbers

abstract:
  For an arbitrary Radon measure $\mu$ we estimate the integrated discrete
curvature of $\mu$ in terms of its centred variant of Jones' beta numbers. We
farther relate integrals of centred and non-centred beta numbers. As a
corollary, employing the recent result of Tolsa [Calc. Var. PDE, 2015], we
obtain a partial converse of the theorem of Meurer [arXiv:1510.04523].


title: An efficient perturbation theory of density matrix renormalization group

abstract:
  Density matrix renormalization group (DMRG) is one of the most powerful
numerical methods available for many-body systems. In this work, we develop a
perturbation theory of DMRG (PT-DMRG) to largely increase its accuracy in an
extremely simple and efficient way. By using the canonical matrix product state
(MPS) representation for the ground state of the considered system, a set of
orthogonal basis functions $\left\lbrace | \psi_i \rangle \right\rbrace$ is
introduced to describe the perturbations to the ground state obtained by the
conventional DMRG. The Schmidt numbers of the MPS that are beyond the bond
dimension cut-off are used to define such perturbation terms. The perturbed
Hamiltonian is then defined as $\tilde{H}_{ij}= \langle \psi_i | \hat{H} |
\psi_j \rangle$; its ground state permits to calculate physical observables
with a considerably improved accuracy as compared to the original DMRG results.
We benchmark the second-order perturbation theory with the help of
one-dimensional Ising chain in a transverse field and the Heisenberg chain,
where the precision of DMRG is shown to be improved $\rm O(10)$ times.
Furthermore, for moderate length $L$ the errors of DMRG and PT-DMRG both scale
linearly with $L^{-1}$. The linear relation between the dimension cut-off of
DMRG and that of PT-DMRG with the same precision shows a considerable
improvement of efficiency, especially for large dimension cut-off's. In
thermodynamic limit we show that the errors of PT-DMRG scale with
$\sqrt{L^{-1}}$. Our work suggests an effective way to define the tangent space
of the ground state MPS, which may shed lights on the properties beyond the
ground state. Such second-order PT-DMRG can be readily generalized to higher
orders, as well as applied to the models in higher dimensions.


title:
e$^{+}$/e$^{-}$ Discrimination in Liquid Scintillator and Its Usage to
  Suppress $^{8}$He/$^{9}$Li Backgrounds

abstract:
  Reactor neutrino experiments build large-scale detector systems to detect
neutrinos. In liquid scintillator, a neutral bound state of a positron and an
electron, named positronium, can be formed. The spin triplet state is called
ortho-positronium (o-Ps). In this article, an experiment is designed to measure
the lifetime of o-Ps, giving a result of 3.1 ns. A PSD parameter based on
photon emission time distribution (PETD) was constructed to discriminate
e$^+$/e$^-$. Finally, the application of e$^+$/e$^-$ discrimination in the JUNO
experiment is shown. It helps suppress $^{8}$He/$^{9}$Li backgrounds and
improves the sensitivity by 0.6 in $\chi^2$ analysis with an assumption of
$\sigma$=1 ns PMT Transit Time Spread, which will bring a smearing effect to
the PETD.


title: TheanoLM - An Extensible Toolkit for Neural Network Language Modeling

abstract:
  We present a new tool for training neural network language models (NNLMs),
scoring sentences, and generating text. The tool has been written using Python
library Theano, which allows researcher to easily extend it and tune any aspect
of the training process. Regardless of the flexibility, Theano is able to
generate extremely fast native code that can utilize a GPU or multiple CPU
cores in order to parallelize the heavy numerical computations. The tool has
been evaluated in difficult Finnish and English conversational speech
recognition tasks, and significant improvement was obtained over our best
back-off n-gram models. The results that we obtained in the Finnish task were
compared to those from existing RNNLM and RWTHLM toolkits, and found to be as
good or better, while training times were an order of magnitude shorter.


title:
Switching dynamics of morphology-structure in chemically deposited
  carbon films -a new insight

abstract:
  Carbon is one of the most investigated materials and shows chaotic behavior
in terms of evolving structure. Synthesizing carbon materials largely depend on
the deposition technique, process parameters, condition of substrate surface
and ratios of the gaseous chemistry. A variety of techniques have been employed
to depositing carbon films from various gaseous mixtures to different substrate
materials. In this study, carbon thin and thick films are discussed for
different techniques known as hot filament chemical vapor deposition and
microwave plasma chemical vapor deposition where their synthesis process has
been explained in a new context. Here, we discuss attained dynamics of atoms or
tiny grains amalgamating into a particular phase of grain or crystallite and
electron-dynamics responsible for binding atoms in the formation of all sorts
of tiny grains, grains and crystallites controlling overall
morphology-structure of films thickness at few nanometers to several microns.
Carbon atoms when in solid state, on amalgamation at flat surface result into
bind under uniform electron-dynamics and when the amalgamation is at uneven
surface, they result into bind under non-uniform electron-dynamics. Substrates
under appropriate surface defects or abrasion result into an improved rate of
nucleation of tiny grains, hence, their increased rate of growth. This study
embarks on unexplored science of carbon films where in addition to localized
process parameters nature of substrate also influence dynamics of formation of
tiny clusters, grains and crystallites at their initial stage of formation. Our
results and discussions enlighten us to revisit the nucleation and growth
mechanisms of different sorts of films deposit at any scale and at any
substrate surface constituting different composition.


title: On the ergodicity of perpendicular cosmic ray transport

abstract:
  Aims. The random walk of energetic charged particles in turbulent magnetic
fields is investigated. Special focus is placed on transport across the mean
magnetic field, which had been found to be subdiffusive on many occasions.
Therefore, a characterization using the concept of ergodicity is attempted by
noting the connection to the time evolution of the mean-square displacement.
Methods. Based on the test-particle approach, a numerical Monte-Carlo
simulation code is used to integrate the equation of motion for particles that
are scattered by magnetic turbulence. The turbulent fields are generated by
superposing plane waves with a Kolmogorov-type power spectrum. The individual
particle trajectories are then used to calculate a variety of statistical
quantities. Results. The simulation results clearly demonstrate how the
heterogeneity of the particle ensemble causes the system to be weakly
non-ergodic. In addition, it is shown how the step length distribution varies
with the particle energy. In conclusion, cross-field transport is non-Gaussian
but still almost diffusive.


title: An example of a $P$-minimal structure without definable Skolem functions

abstract:
  We show there are intermediate $P$-minimal structures between the
semi-algebraic and sub-analytic languages which do not have definable Skolem
functions. As a consequence, by a result of Mourgues, this shows there are
$P$-minimal structures which do not admit classical cell decomposition.


title: Families of $2$-weights of some particular graphs

abstract:
  Let ${\cal G}=(G,w) $ be a positive-weighted graph, that is a graph $G$
endowed with a function $w$ from the edge set of $G$ to the set of positive
real numbers; for any distinct vertices $i,j $, we define $D_{i,j}({\cal G})$
to be the weight of the path in $G$ joining $i$ and $j$ with minimum weight. In
this paper we fix a particular class of graphs and we give a criterion to
establish whether, given a family of positive real numbers $\{D_I\}_{I \in {
\{1,...., n\} \choose 2}}$, there exists a positive-weighted graph ${\cal G}
=(G,w) $ in the class we have fixed, with vertex set equal to $\{1,....,n\}$
and such that $D_I ({\cal G}) =D_I$ for any $I \in { \{1,...., n\} \choose 2}$.
In particular, the classes of graphs we consider are the following: snakes,
caterpillars, polygons, bipartite graphs, complete graphs, planar graphs.


title: Distributed Frequency Control in Power Grids Under Limited Communication

abstract:
  In this paper, we analyze the impact of communication failures on the
performance of optimal distributed frequency control. We consider a
consensus-based control scheme, and show that it does not converge to the
optimal solution when the communication network is disconnected. We propose a
new control scheme that uses the dynamics of power grid to replicate the
information not received from the communication network, and prove that it
achieves the optimal solution under any single communication link failure. In
addition, we show that this control improves cost under multiple communication
link failures. Next, we analyze the impact of discrete-time communication on
the performance of distributed frequency control. In particular, we will show
that the convergence time increases as the time interval between two messages
increases. We propose a new algorithm that uses the dynamics of the power grid,
and show through simulation that it improves the convergence time of the
control scheme significantly.


title:
Narrowband Gyrosynchrotron Bursts: Probing Electron Acceleration in
  Solar Flares

abstract:
  Recently, in a few case studies we demonstrated that gyrosynchrotron
microwave emission can be detected directly from the acceleration region when
the trapped electron component is insignificant. For the statistical study
reported here, we have identified events with steep (narrowband) microwave
spectra that do not show a significant trapped component and at the same time
show evidence of source uniformity, which simplifies the data analysis greatly.
Initially, we identified a subset of more than 20 radio bursts with such narrow
spectra, having low- and high-frequency spectral indices larger than 3 in
absolute value. A steep low-frequency spectrum implies that the emission is
nonthermal (for optically-thick thermal emission, the spectral index cannot be
steeper than 2), and the source is reasonably dense and uniform. A steep
high-frequency spectrum implies that no significant electron trapping occurs;
otherwise a progressive spectral flattening would be observed. Roughly half of
these radio bursts have RHESSI data, which allows for detailed, joint
diagnostics of the source parameters and evolution. Based on an analysis of
radio-to-X-ray spatial relationships, timing, and spectral fits, we conclude
that the microwave emission in these narrowband bursts originates directly from
the acceleration regions, which have relatively strong magnetic field, high
density, and low temperature. In contrast, the thermal X-ray emission comes
from a distinct loop with smaller magnetic field, lower density, but higher
temperature. Therefore, these flares occurred likely due to interaction between
two (or more) magnetic loops.


title:
Modelling the Nonlinear Response of Fibre-reinforced Bending Fluidic
  Actuators

abstract:
  Soft actuators are receiving increasing attention from the engineering
community, not only in research but even for industrial applications. Among
soft actuators, fibre-reinforced Bending Fluidic Actuators (BFAs) became very
popular thanks to features such as robustness and easy design and fabrication.
However, an accurate modelling of these smart structures, taking into account
all the nonlinearities involved, is a challenging task. In this effort, we
propose an analytical mechanical model to capture the quasi-static response of
fibre-reinforced BFAs. The model is fully 3D and for the first time includes
the effect of the pressure on the lateral surface of the chamber as well as the
non-constant torque produced by the pressure at the tip. The presented model
can be used for design and control, while providing information about the
mechanics of these complex actuators.


title: Markov Chains and Unambiguous Automata

abstract:
  Unambiguous automata are nondeterministic automata in which every word has at
most one accepting run. In this paper we give a polynomial-time algorithm for
model checking discrete-time Markov chains against $\omega$-regular
specifications represented as unambiguous automata. We furthermore show that
the complexity of this model checking problem lies in NC: the subclass of P
comprising those problems solvable in poly-logarithmic parallel time. These
complexity bounds match the known bounds for model checking Markov chains
against specifications given as deterministic automata, notwithstanding the
fact that unambiguous automata can be exponentially more succinct than
deterministic automata. We report on an implementation of our procedure,
including an experiment in which the implementation is used to model check LTL
formulas on Markov chains.


title:
Measurement of forward $W$ and $Z$ boson production in association with
  jets in proton-proton collisions at $\sqrt{s}=8$ TeV

abstract:
  The production of $W$ and $Z$ bosons in association with jets is studied in
the forward region of proton-proton collisions collected at a centre-of-mass
energy of 8 TeV by the LHCb experiment, corresponding to an integrated
luminosity of 1.98 $\pm$ 0.02 fb$^{-1}$. The $W$ boson is identified using its
decay to a muon and a neutrino, while the $Z$ boson is identified through its
decay to a muon pair. Total cross-sections are measured and combined into
charge ratios, asymmetries, and ratios of $W+$jet and $Z$+jet production
cross-sections. Differential measurements are also performed as a function of
both boson and jet kinematic variables. All results are in agreement with
Standard Model predictions.


title:
The variable metric forward-backward splitting algorithm under mild
  differentiability assumptions

abstract:
  We study the variable metric forward-backward splitting algorithm for convex
minimization problems without the standard assumption of the Lipschitz
continuity of the gradient. In this setting, we prove that, by requiring only
mild assumptions on the smooth part of the objective function and using several
types of line search procedures for determining either the gradient descent
stepsizes, or the relaxation parameters, one still obtains weak convergence of
the iterates and convergence in the objective function values. Moreover, the
$o(1/k)$ convergence rate in the function values is obtained if slightly
stronger differentiability assumptions are added. We also illustrate several
applications including problems that involve Banach spaces and functions of
divergence type.


title: A Non-associative Baker-Campbell-Hausdorff formula

abstract:
  We address the problem of constructing the non-associative version of the
Dynkin form of the Baker-Campbell-Hausdorff formula; that is, expressing $\log
(\exp (x)\exp(y))$, where $x$ and $y$ are non-associative variables, in terms
of the Shestakov-Umirbaev primitive operations. In particular, we obtain a
recursive expression for the Magnus expansion of the Baker-Campbell-Hausdorff
series and an explicit formula in degrees smaller than 5. Our main tool is a
non-associative version of the Dynkin-Specht-Wever Lemma. A construction of
Bernouilli numbers in terms of binary trees is also recovered.


title: ${\rm SO}(n)$ covariant local tensor valuations on polytopes

abstract:
  The Minkowski tensors are valuations on the space of convex bodies in
${\mathbb R}^n$ with values in a space of symmetric tensors, having additional
covariance and continuity properties. They are extensions of the intrinsic
volumes, and as these, they are the subject of classification theorems, and
they admit localizations in the form of measure-valued valuations. For these
local tensor valuations, restricted to convex polytopes, a classification
theorem has been proved recently, under the assumption of isometry covariance,
but without any continuity assumption. This characterization result is extended
here, replacing the covariance under orthogonal transformations by invariance
under proper rotations only. This yields additional local tensor valuations on
polytopes in dimensions two and three, but not in higher dimensions. They are
completely classified in this paper.


title: High-Performance Complementary III-V Tunnel FETs with Strain Engineering

abstract:
  Strain engineering has recently been explored to improve tunnel field-effect
transistors (TFETs). Here, we report design and performance of strained
ultra-thin-body (UTB) III-V TFETs by quantum transport simulations. It is found
that for an InAs UTB confined in [001] orientation, uniaxial compressive strain
in [100] or [110] orientation shrinks the band gap meanwhile reduces
(increases) transport (transverse) effective masses. Thus it improves the ON
state current of both n-type and p-type UTB InAs TFETs without lowering the
source density of states. Applying the strain locally in the source region
makes further improvements by suppressing the OFF state leakage. For p-type
TFETs, the locally strained area can be extended into the channel to form a
quantum well, giving rise to even larger ON state current that is comparable to
the n-type ones. Therefore strain engineering is a promising option for
improving complementary circuits based on UTB III-V TFETs.


title:
Multidimensionally-constrained covariant density functional theories ---
  nuclear shapes and potential energy surfaces

abstract:
  The intrinsic nuclear shapes deviating from a sphere not only manifest
themselves in nuclear collective states but also play important roles in
determining nuclear potential energy surfaces (PES's) and fission barriers. In
order to describe microscopically and self-consistently nuclear shapes and
PES's with as many shape degrees of freedom as possible included, we developed
multidimensionally-constrained covariant density functional theories
(MDC-CDFTs). In MDC-CDFTs, the axial symmetry and the reflection symmetry are
both broken and all deformations characterized by $\beta_{\lambda\mu}$ with
even $\mu$ are considered. We have used the MDC-CDFTs to study PES's and
fission barriers of actinides, the non-axial octupole $Y_{32}$ correlations in
$N = 150$ isotones and shapes of hypernuclei. In this Review we will give
briefly the formalism of MDC-CDFTs and present the applications to normal
nuclei.


title:
Bloom Filters and Compact Hash Codes for Efficient and Distributed Image
  Retrieval

abstract:
  This paper presents a novel method for efficient image retrieval, based on a
simple and effective hashing of CNN features and the use of an indexing
structure based on Bloom filters. These filters are used as gatekeepers for the
database of image features, allowing to avoid to perform a query if the query
features are not stored in the database and speeding up the query process,
without affecting retrieval performance. Thanks to the limited memory
requirements the system is suitable for mobile applications and distributed
databases, associating each filter to a distributed portion of the database.
Experimental validation has been performed on three standard image retrieval
datasets, outperforming state-of-the-art hashing methods in terms of precision,
while the proposed indexing method obtains a $2\times$ speedup.


title:
Negative dynamic conductivity of a current driven array of graphene
  nanoribbons

abstract:
  We consider a periodic array of graphene nanoribbons under the action of a
strong dc electric field $E_0$ and an external electromagnetic excitation with
the frequency $\omega$ and the lateral wave vector $q$. Solving the
quasi-classical Boltzmann kinetic equation and calculating the surface dynamic
conductivity $\sigma_{2D}(q,\omega,E_0)$ and the absorption coefficient of such
a system we show that the real part of the conductivity and the absorption
coefficient may become negative under certain conditions. Physically this
corresponds to the amplification of the electromagnetic waves at the expense of
the energy of the direct current source. The results are discussed in
connection with experiments on the surface acoustic waves and on the
Smith-Purcell-type graphene-based terahertz emitter.


title:
Personalized Risk Scoring for Critical Care Patients using Mixtures of
  Gaussian Process Experts

abstract:
  We develop a personalized real time risk scoring algorithm that provides
timely and granular assessments for the clinical acuity of ward patients based
on their (temporal) lab tests and vital signs. Heterogeneity of the patients
population is captured via a hierarchical latent class model. The proposed
algorithm aims to discover the number of latent classes in the patients
population, and train a mixture of Gaussian Process (GP) experts, where each
expert models the physiological data streams associated with a specific class.
Self-taught transfer learning is used to transfer the knowledge of latent
classes learned from the domain of clinically stable patients to the domain of
clinically deteriorating patients. For new patients, the posterior beliefs of
all GP experts about the patient's clinical status given her physiological data
stream are computed, and a personalized risk score is evaluated as a weighted
average of those beliefs, where the weights are learned from the patient's
hospital admission information. Experiments on a heterogeneous cohort of 6,313
patients admitted to Ronald Regan UCLA medical center show that our risk score
outperforms the currently deployed risk scores, such as MEWS and Rothman
scores.


title: Chiral spin-3/2 particles in a medium

abstract:
  We consider the propagation of a chiral spin-3/2 particle in a background
medium using the Thermal Field Theory (TFT) method, in analogy to the cases of
a spin-1/2 fermion (e.g., a neutrino) and the photon. We present a systematic
decomposition of the thermal self-energy, from which the dispersion relation of
the modes that propagate in the medium are obtained. We find that there are
several modes and in each case we obtain the equation for the dispersion
relation as well as the corresponding spin-3/2 spinor. As an example of the
general procedure and results, we consider a model in which the chiral spin-3/2
particle couples to a spin-1/2 fermion and a scalar particle, and propagates in
a thermal background composed of such particles. The dispersion relations and
corresponding spinors are detemined explcitly in this case from the 1-loop TFT
expression for the self-energy. The results in this case share some resemblance
and analogies with the photon and the chiral fermion cases but, as already
noted, there are also differences. The present work provides the groundwork for
considering problems related to the properties of chiral spin-3/2 particles in
a medium, in analogy to the case of neutrinos for example, which can be
relevant in physical contexts of current interest.


title:
Hierarchical Modeling of Multidimensional Data in Regularly Decomposed
  Spaces: Main Principles

abstract:
  The described works have been carried out in the framework of a mid-term
study initiated by the Centre Electronique de l'Armement and led by ADERSA, a
French company of research under contract. The aim was to study the techniques
of regular dividing of numerical data sets so as to provide tools for problem
solving enabling to model multidimensional numerical objects and to be used in
computer-aided design and manufacturing, in robotics, in image analysis and
synthesis, in pattern recognition, in decision making, in cartography and
numerical data base management. These tools are relying on the principle of
regular hierarchical decomposition and led to the implementation of a
multidimensional generalization of quaternary and octernary trees: the trees of
order 2**k or 2**k-trees mapped in binary trees. This first tome, dedicated to
the hierarchical modeling of multidimensional numerical data, describes the
principles used for building, transforming, analyzing and recognizing patterns
on which is relying the development of the associated algorithms. The whole so
developed algorithms are detailed in pseudo-code at the end of this document.
The present publication especially describes: - a building method adapted
disordered and overcrowded data streams ; - its extension in inductive limits ;
- the computation of the homographic transformation of a tree ; - the attribute
calculus based on generalized moments and the provision of Eigen trees ; -
perception procedures of objects without any covering in affine geometry ; -
several supervised and unsupervised pattern recognition methods.


title:
Does disaggregated electricity feedback reduce domestic electricity
  consumption? A systematic review of the literature

abstract:
  We examine 12 studies on the efficacy of disaggregated energy feedback. The
average electricity reduction across these studies is 4.5%. However, 4.5% may
be a positively-biased estimate of the savings achievable across the entire
population because all 12 studies are likely to be prone to opt-in bias hence
none test the effect of disaggregated feedback on the general population.
Disaggregation may not be required to achieve these savings: Aggregate feedback
alone drives 3% reductions; and the 4 studies which directly compared aggregate
feedback against disaggregated feedback found that aggregate feedback is at
least as effective as disaggregated feedback, possibly because web apps are
viewed less often than in-home-displays (in the short-term, at least) and
because some users do not trust fine-grained disaggregation (although this may
be an issue with the specific user interface studied). Disaggregated
electricity feedback may help a motivated sub-group of the population to save
more energy but fine-grained disaggregation may not be necessary to achieve
these energy savings. Disaggregation has many uses beyond those discussed in
this paper but, on the specific question of promoting energy reduction in the
general population, there is no robust evidence that current forms of
disaggregated energy feedback are more effective than aggregate energy
feedback. The effectiveness of disaggregated feedback may increase if the
general population become more energy-conscious (e.g. if energy prices rise or
concern about climate change deepens); or if users' trust in fine-grained
disaggregation improves; or if innovative new approaches or alternative
disaggregation strategies (e.g. disaggregating by behaviour rather than by
appliance) out-perform existing feedback. We also discuss opportunities for new
research into the effectiveness of disaggregated feedback.


title: Blob dynamics in TORPEX poloidal null configurations

abstract:
  Three dimensional blob dynamics are simulated in X-point magnetic
configurations in the TORPEX device via a non-field-aligned coordinate system,
using an isothermal model which evolves density, vorticity, parallel velocity
and parallel current density. By modifying the parallel gradient operator to
include perpendicular perturbations from poloidal field coils, numerical
singularities associated with field aligned coordinates are avoided. A
comparison with a previously developed analytical model is performed and an
agreement is found with minimal modification. Experimental comparison
determines that the null region can cause an acceleration of filaments due to
increasing connection length, but this acceleration is small relative to other
effects, which we quantify. Experimental measurements are reproduced, and the
dominant acceleration mechanism is identified as that of a developing dipole in
a moving background. Contributions from increasing connection length close to
the null point are a small correction.


title: Anyons in quantum mechanics with a minimal length

abstract:
  The existence of anyons, \textit{i.e.} quantum states with an arbitrary spin,
is a generic feature of standard quantum mechanics in $(2+1)-$dimensional
Minkowski spacetime. Here it is shown that relativistic anyons may exist also
in quantum theories where a minimal length is present. The interplay between
minimal length and arbitrary spin effects are discussed.


title: Exotic $\mathbb{R}^4$'s and positive isotropic curvature

abstract:
  We show that no exotic $\mathbb{R}^4$ admits a complete Riemannian metric
with uniformly positive isotropic curvature and with bounded geometry. This is
essentially a corollary of the main result in [Hu1], and was stated in [Hu2]
without proof. In the process of the proof we also show that the diffeomorphism
type of an infinite connected sum of some connected smooth $n$-manifolds
($n\geq 2$) according to a locally finite graph does not depend on the gluing
maps used.


title:
Maps of the Magellanic Clouds from Combined South Pole Telescope and
  Planck Data

abstract:
  We present maps of the Large and Small Magellanic Clouds from combined South
Pole Telescope (SPT) and Planck data. The Planck satellite observes in nine
bands, while the SPT data used in this work were taken with the three-band
SPT-SZ camera, The SPT-SZ bands correspond closely to three of the nine Planck
bands, namely those centered at 1.4, 2.1, and 3.0 mm. The angular resolution of
the Planck data ranges from 5 to 10 arcmin, while the SPT resolution ranges
from 1.0 to 1.7 arcmin. The combined maps take advantage of the high resolution
of the SPT data and the long-timescale stability of the space-based Planck
observations to deliver robust brightness measurements on scales from the size
of the maps down to ~1 arcmin. In each band, we first calibrate and
color-correct the SPT data to match the Planck data, then we use noise
estimates from each instrument and knowledge of each instrument's beam to make
the inverse-variance-weighted combination of the two instruments' data as a
function of angular scale. We create maps assuming a range of underlying
emission spectra and at a range of final resolutions. We perform several
consistency tests on the combined maps and estimate the expected noise in
measurements of features in the maps. We compare maps from this work to maps
from the Herschel HERITAGE survey, finding general consistency between the
datasets. All data products described in this paper are available for download
from the NASA Legacy Archive for Microwave Background Data Analysis server.


title:
Hierarchical Modeling of Multidimensional Data in Regularly Decomposed
  Spaces: Implementation on Computer

abstract:
  The described works have been carried out in the framework of a mid-term
study initiated by the Centre Electronique de l'Armement, then by an advanced
study launched by the Direction de la Recherche et des Etudes Technologiques in
France in the aim to develop new techniques for multidimensional hierarchical
modeling and to port them on parallel architecture computers for satisfying the
future needs in processing huge numerical data bases. Following the first tome
describing the modeling principles, the second tome details the way used for
developing the modeling software and for porting it on different computers,
especially on parallel architecture computers. In addition to these works, it
is gone through new algorithms that have been developed after those that have
been presented in the former tome and that are described in pseudo-code in
annex of the present document: - operators for constructive geometry (building
simple shapes, Boolean operators, slice handling); - integral transformations
(epigraph, hypograph, convex hull) ; - homotopic transformations (boundary,
erosion, dilation, opening, closing) ; - median transformations (median
filtering, thinning, median set, intrinsic dimension) ; - transformations of
(hyper-)surface manifolds (median filtering, extension, polynomial fitting of a
simple function). The present publication is ending with the software porting
on two distributed memory parallel computers: - a thin-grained synchronous
computer ; - a coarse-grained asynchronous computer.


title:
Tracking Dengue Epidemics using Twitter Content Classification and Topic
  Modelling

abstract:
  Detecting and preventing outbreaks of mosquito-borne diseases such as Dengue
and Zika in Brasil and other tropical regions has long been a priority for
governments in affected areas. Streaming social media content, such as Twitter,
is increasingly being used for health vigilance applications such as flu
detection. However, previous work has not addressed the complexity of drastic
seasonal changes on Twitter content across multiple epidemic outbreaks. In
order to address this gap, this paper contrasts two complementary approaches to
detecting Twitter content that is relevant for Dengue outbreak detection,
namely supervised classification and unsupervised clustering using topic
modelling. Each approach has benefits and shortcomings. Our classifier achieves
a prediction accuracy of about 80\% based on a small training set of about
1,000 instances, but the need for manual annotation makes it hard to track
seasonal changes in the nature of the epidemics, such as the emergence of new
types of virus in certain geographical locations. In contrast, LDA-based topic
modelling scales well, generating cohesive and well-separated clusters from
larger samples. While clusters can be easily re-generated following changes in
epidemics, however, this approach makes it hard to clearly segregate relevant
tweets into well-defined clusters.


title: Schr\"odinger-like quantum dynamics in loop quantized black holes

abstract:
  We show, following a previous quantization of a vacuum spherically symmetric
spacetime carried out in Ref. \cite{gop}, that this setting admits a
Schr\"odinger-like picture. More precisely, the technique adopted there for the
definition of parametrized Dirac observables (that codify local information of
the quantum theory) can be extended in order to accommodate different pictures.
In this new picture, the quantum states are parametrized in terms of suitable
gauge parameters and the observables constructed out of the kinematical ones on
this space of parametrized states.


title:
Arbitrary-dimensional teleportation of optical number states with linear
  optics

abstract:
  Quantum state teleportation of optical number states is conspicuously absent
from the list of experimental milestones achieved to date. Here we demonstrate
analytically a teleportation scheme with fidelity $100\%$ for optical number
states of arbitrary dimension using linear optical elements only. To this end,
we develop an EPR source to supply Bell-type states for the teleportation, and
show how the same set-up can also be used as a Bell-state analyser (BSA) when
implemented in a time-reversal manner. These two aspects are then brought
together to complete the teleportation protocol in a scheme that can deliver
perfect fidelity, albeit with an efficiency that decays exponentially as the
occupation of the number states increases stepwise. The EPR source and BSA
schemes both consist of two optical axes in a symmetrical V-shape experimental
layout, along which beam-splitters are placed cross-beam fashion at regular
intervals, with their transmittivities treated as variables for which the
values are calculated ad hoc. In particular, we show the full treatment for the
case of qutrit teleportation, and calculate the transmittivity values of the
beam splitters required for teleporting qubits, qutrits, qupentits, quheptits
and qunits. The general case for arbitrary-dimensional number state
teleportation is demonstrated through a counting argument.


title:
Phase 1: DCL System Research Using Advanced Approaches for Land-based or
  Ship-based Real-Time Recognition and Localization of Marine Mammals - HPC
  System Implementation

abstract:
  We aim to investigate advancing the state of the art of detection,
classification and localization (DCL) in the field of bioacoustics. The two
primary goals are to develop transferable technologies for detection and
classification in: (1) the area of advanced algorithms, such as deep learning
and other methods; and (2) advanced systems, capable of real-time and archival
and processing. This project will focus on long-term, continuous datasets to
provide automatic recognition, minimizing human time to annotate the signals.
Effort will begin by focusing on several years of multi-channel acoustic data
collected in the Stellwagen Bank National Marine Sanctuary (SBNMS) between 2006
and 2010. Our efforts will incorporate existing technologies in the
bioacoustics signal processing community, advanced high performance computing
(HPC) systems, and new approaches aimed at automatically detecting-classifying
and measuring features for species-specific marine mammal sounds within passive
acoustic data.


title:
Phase 2: DCL System Using Deep Learning Approaches for Land-based or
  Ship-based Real-Time Recognition and Localization of Marine Mammals - Machine
  Learning Detection Algorithms

abstract:
  Overarching goals for this work aim to advance the state of the art for
detection, classification and localization (DCL) in the field of bioacoustics.
This goal is primarily achieved by building a generic framework for
detection-classification (DC) using a fast, efficient and scalable
architecture, demonstrating the capabilities of this system using on a variety
of low-frequency mid-frequency cetacean sounds. Two primary goals are to
develop transferable technologies for detection and classification in, one: the
area of advanced algorithms, such as deep learning and other methods; and two:
advanced systems, capable of real-time and archival processing. For each key
area, we will focus on producing publications from this work and providing
tools and software to the community where/when possible. Currently massive
amounts of acoustic data are being collected by various institutions,
corporations and national defense agencies. The long-term goal is to provide
technical capability to analyze the data using automatic algorithms for (DC)
based on machine intelligence. The goal of the automation is to provide
effective and efficient mechanisms by which to process large acoustic datasets
for understanding the bioacoustic behaviors of marine mammals. This capability
will provide insights into the potential ecological impacts and influences of
anthropogenic ocean sounds. This work focuses on building technologies using a
maturity model based on DARPA 6.1 and 6.2 processes, for basic and applied
research, respectively.


title:
Inexact Alternating Optimization for Phase Retrieval In the Presence of
  Outliers

abstract:
  Phase retrieval has been mainly considered in the presence of Gaussian noise.
However, the performance of the algorithms proposed under the Gaussian noise
model severely degrades when grossly corrupted data, i.e., outliers, exist.
This paper investigates techniques for phase retrieval in the presence of
heavy-tailed noise -- which is considered a better model for situations where
outliers exist. An $\ell_p$-norm ($0<p<2$) based estimator is proposed for
fending against such noise, and two-block inexact alternating optimization is
proposed as the algorithmic framework to tackle the resulting optimization
problem. Two specific algorithms are devised by exploring different local
approximations within this framework. Interestingly, the core conditional
minimization steps can be interpreted as iteratively reweighted least squares
and gradient descent. Convergence properties of the algorithms are discussed,
and the Cram\'er-Rao bound (CRB) is derived. Simulations demonstrate that the
proposed algorithms approach the CRB and outperform state-of-the-art algorithms
in heavy-tailed noise.


title: From the Newton equation to the wave equation : the case of shock waves

abstract:
  We study the macroscopic limit of a chain of atoms governed by the Newton
equation. It is known from the work of Blanc, Le Bris, Lions, that this limit
is the solution of a nonlinear wave equation, as long as this solution remains
smooth. We show, numerically and mathematically that, if the distances between
particles remain bounded, it is not the case any more when there are shocks -at
least for a convex nearest-neighbour interaction potential with convex
derivative.


title: Breaking the Limits -- Redefining the Instantaneous Frequency

abstract:
  The Carson and Fry (1937) introduced the concept of variable frequency as a
generalization of the constant frequency. The instantaneous frequency (IF) is
the time derivative of the instantaneous phase and it is well-defined only when
this derivative is positive. If this derivative is negative, the IF creates
problem because it does not provide any physical significance. This study
proposes a mathematical solution and eliminate this problem by redefining the
IF such that it is valid for all monocomponent and multicomponent signals which
can be nonlinear and nonstationary in nature. This is achieved by using the
property of the multivalued inverse tangent function. The efforts and
understanding of all the methods based on the IF would improve significantly by
using this proposed definition of the IF. We also demonstrate that the
decomposition of a signal, using zero-phase filtering based on the well
established Fourier and filter theory, into a set of desired frequency bands
with proposed IF produces accurate time-frequency-energy (TFE) distribution
that reveals true nature of signal. Simulation results demonstrate the efficacy
of the proposed IF that makes zero-phase filter based decomposition most
powerful, for the TFE analysis of a signal, as compared to other existing
methods in the literature.


title: Isoparametric hypersurfaces with four principal curvatures, IV

abstract:
  We prove that an isoparametric hypersurface with four principal curvatures
and multiplicity pair $(7,8)$ is either the one constructed by Ozeki and
Takeuchi, or one of the two constructed by Ferus, Karcher, and M\"{u}nzner.
This completes the classification of isoparametric hypersurfaces in spheres
that \'{E}. Cartan initiated in the late 1930s.


title:
Blackwell-Nash Equilibrium for Discrete and Continuous Time Stochastic
  Games

abstract:
  We consider both discrete and continuous time finite state-action stochastic
games. In discrete time stochastic games, it is known that a stationary
Blackwell-Nash equilibrium (BNE) exists for a single controller additive reward
(SC-AR) stochastic game which is a special case of a general stochastic game.
We show that, in general, the additive reward condition is needed for the
existence of a BNE. We give an example of a single controller stochastic game
which does not satisfy additive reward condition. We show that this example
does not have a stationary BNE. For a general discrete time discounted
stochastic game we give two different sets of conditions and show that a
stationary Nash equilibrium that satisfies any set of conditions is a BNE. One
of these sets of conditions weakens a set of conditions available in the
literature. For continuous time stochastic games, we give an example that does
not have a stationary BNE. In fact, this example is a single controller
continuous time stochastic game. Then, we introduce a continuous time SC-AR
stochastic game. We show that there always exists a stationary deterministic
BNE for continuous time SC-AR stochastic game. For a general continuous time
discounted stochastic game we give two different sets of conditions and show
that a Nash equilibrium that satisfies any set of conditions is a BNE.


title: DAHA and plane curve singularities

abstract:
  We suggest a relatively simple and totally geometric conjectural description
of uncolored DAHA superpolynomials of arbitrary algebraic knots (conjecturally
coinciding with the reduced stable Khovanov-Rozansky polynomials) via the
flagged Jacobian factors (new objects) of the corresponding unibranch plane
curve singularities. This generalizes the Cherednik-Danilenko conjecture on the
Betti numbers of Jacobian factors, the Gorsky combinatorial conjectural
interpretation of superpolynomials of torus knots and that by Gorsky-Mazin for
their constant term. The paper mainly focuses on non-torus algebraic knots. A
connection with the conjecture due to Oblomkov-Rasmussen-Shende is possible,
but our approach is different. A motivic version of our conjecture is related
to p-adic orbital A-type integrals for anisotropic centralizers.


title: Gaussian Two-Way Channels With Discrete Inputs and Quantized Outputs

abstract:
  In this paper, Gaussian two-way channel with uniform output quantization is
studied. For Gaussian inputs, the optimum uniform finite-level quantizer is
determined numerically for different values of Signal-to-Noise Ratio (SNR). The
two-way channel with constellation-based transmitters is then investigated. A
formulation for the so-called Shannon achievable region of this channel is
developed and numerical computations of this region are presented for
particular constellations. It is shown that if one transmitter utilizes a
rotated version of the constellation used at the other transmitter, the Shannon
achievable region can be enlarged


title: Riemann-Roch for homotopy invariant K-theory and Gysin morphisms

abstract:
  We prove the Riemann-Roch theorem for homotopy invariant $K$-theory and
projective local complete intersection morphisms between finite dimensional
noetherian schemes, without smoothness assumptions. We also prove a new
Riemann-Roch theorem for the relative cohomology of a morphism.
  In order to do so, we construct and characterize Gysin morphisms for regular
immersions between cohomologies represented by spectra (examples include
homotopy invariant $K$-theory, motivic cohomology, their arithmetic
counterparts, real absolute Hodge and Deligne-Beilinson cohomology, rigid
syntomic cohomology, mixed Weil cohomologies) and use this construction to
prove a motivic version of the Riemann-Roch.


title: Asymmetric exchange in flocks

abstract:
  As the constituents of a flock are polar, one expects a fore-aft asymmetry in
their interactions. We show here that the resulting antisymmetric part of the
"exchange coupling" between a bird and its neighbours, if large enough,
destabilizes the flock through spontaneous turning of the birds. The same
asymmetry also yields a natural mechanism for a difference between the speed of
advection of information along the flock and the speed of the flock itself. We
show that the absence of detailed balance, and not merely the breaking of
Galilean invariance, is responsible for this difference. We delineate the
conditions on parameters and wavenumber for the existence of the turning
instability. Lastly we present an alternative perspective based on
flow-alignment effects in an active liquid crystal with turning inertia in
contact with a momentum sink.

categories: cond-mat.stat-mech cond-mat.soft physics.bio-ph physics.flu-dyn


title:
Phase 4: DCL System Using Deep Learning Approaches for Land-Based or
  Ship-Based Real-Time Recognition and Localization of Marine Mammals -
  Distributed Processing and Big Data Applications

abstract:
  While the animal bioacoustics community at large is collecting huge amounts
of acoustic data at an unprecedented pace, processing these data is
problematic. Currently in bioacoustics, there is no effective way to achieve
high performance computing using commericial off the shelf (COTS) or government
off the shelf (GOTS) tools. Although several advances have been made in the
open source and commercial software community, these offerings either support
specific applications that do not integrate well with data formats in
bioacoustics or they are too general. Furthermore, complex algorithms that use
deep learning strategies require special considerations, such as very large
libraiers of exemplars (whale sounds) readily available for algorithm training
and testing. Detection-classification for passive acoustics is a data-mining
strategy and our goals are aligned with best practices that appeal to the
general data mining and machine learning communities where the problem of
processing large data is common. Therefore, the objective of this work is to
advance the state-of-the art for data-mining large passive acoustic datasets as
they pertain to bioacoustics. With this basic deficiency recognized at the
forefront, portions of the grant were dedicated to fostering deep-learning by
way of international competitions (kaggle.com) meant to attract deep-learning
solutions. The focus of this early work was targeted to make significant
progress in addressing big data systems and advanced algorithms over the
duration of the grant from 2012 to 2015. This early work provided simulataneous
advances in systems-algorithms research while supporting various collaborations
and projects.


title:
Phase 3: DCL System Using Deep Learning Approaches for Land-based or
  Ship-based Real-Time Recognition and Localization of Marine Mammals -
  Bioacoustic Applicaitons

abstract:
  Goals of this research phase is to investigate advanced detection and
classification pardims useful for data-mining passive large passive acoustic
archives. Technical objectives are to develop and refine a High Performance
Computing, Acoustic Data Accelerator (HPC-ADA) along with MATLAB based software
based on time series acoustic signal Detection cLassification using Machine
learning Algorithms, called DeLMA. Data scientists and biologists integrate to
use the HPC-ADA and DeLMA technologies to explore data using newly developed
techniques aimed at inspection of data extracted at large spatial and temporal
scales.


title: Understanding the Onset of Oscillatory Swimming in Microchannels

abstract:
  Self-propelled colloids (swimmers) in confining geometries follow
trajectories determined by hydrodynamic interactions with the bounding
surfaces. However, typically these interactions are ignored or truncated to
lowest order. We demonstrate that higher-order hydrodynamic moments cause
rod-like swimmers to follow oscillatory trajectories in quiescent fluid between
two parallel plates, using a combination of lattice-Boltzmann simulations and
far-field calculations. This behavior occurs even far from the confining walls
and does not require lubrication results. We show that a swimmer's hydrodynamic
quadrupole moment is crucial to the onset of the oscillatory trajectories. This
insight allows us to develop a simple model for the dynamics near the channel
center based on these higher hydrodynamic moments, and suggests opportunities
for trajectory-based experimental characterization of swimmers' hydrodynamic
properties.


title: Alternating Arm Exponents for the Critical Planar Ising Model

abstract:
  We derive the alternating arm exponents of critical Ising model. We obtain
six different patterns of alternating boundary arm exponents which correspond
to the boundary conditions $(\ominus\oplus)$, $(\ominus\text{free})$ and
$(\text{free}\text{free})$, and the alternating interior arm exponents.


title:
Non-symmetric interactions trigger collective swings in globally ordered
  systems

abstract:
  Many systems in nature, from ferromagnets to flocks of birds, exhibit
ordering phenomena on the large scale. In physical systems order is
statistically robust for large enough dimensions, with relative fluctuations
due to noise vanishing with system size. Several biological systems, however,
are less stable than their physical analogues and spontaneously change their
global state on relatively short timescales. In this paper we show that there
are two crucial ingredients in these systems that enhance the effect of noise,
leading to collective changes of state: the non-symmetric nature of
interactions between individuals, and the presence of local heterogeneities in
the topology of the network. The consequences of these features can be larger
the larger the system size leading to a localization of the fluctuation modes
and a relaxation time that remains finite in the thermodynamic limit. The
system keeps changing its global state in time, being constantly driven out of
equilibrium by spontaneous fluctuations. Our results explain what is observed
in several living and social systems and are consistent with recent
experimental data on bird flocks and other animal groups.

categories: cond-mat.stat-mech cond-mat.dis-nn cond-mat.soft physics.bio-ph q-bio.PE


title: A practical attack to Bouftass's cryptosystem

abstract:
  Recently, a new fast public key exchange protocol was presented by S.
Bouftass. The protocol is based on the difficulty of inverting the function
$F(x)=\lfloor (zx \mod 2^p)/ 2^q \rfloor$. In this paper, we describe a
practical attack against this protocol based on Closest Vector Problem (CVP)
and Gaussian lattice reduction.


title: Matrices with high completely positive semidefinite rank

abstract:
  A real symmetric matrix $M$ is completely positive semidefinite if it admits
a Gram representation by (Hermitian) positive semidefinite matrices of any size
$d$. The smallest such $d$ is called the (complex) completely positive
semidefinite rank of $M$, and it is an open question whether there exists an
upper bound on this number as a function of the matrix size. We construct
completely positive semidefinite matrices of size $4k^2+2k+2$ with complex
completely positive semidefinite rank $2^k$ for any positive integer $k$. This
shows that if such an upper bound exists, it has to be at least exponential in
the matrix size. For this we exploit connections to quantum information theory
and we construct extremal bipartite correlation matrices of large rank. We also
exhibit a class of completely positive matrices with quadratic (in terms of the
matrix size) completely positive rank, but with linear completely positive
semidefinite rank, and we make a connection to the existence of Hadamard
matrices.


title:
Did high-energy astrophysical sources contribute to Martian atmospheric
  loss?

abstract:
  Mars is believed to have had a substantial atmosphere in the past.
Atmospheric loss led to depressurization and cooling, and is thought to be the
primary driving force responsible for the loss of liquid water from its
surface. Recently, MAVEN observations have provided new insight into the
physics of atmospheric loss induced by ICMEs and solar wind interacting with
the Martian atmosphere. In addition to solar radiation, it is likely that its
atmosphere has been exposed to radiation bursts from high-energy astrophysical
sources which become highly probable on timescales of ~Gy and beyond. These
sources are capable of significantly enhancing the rates of photoionization and
charged particle-induced ionization in the upper atmosphere. We use Monte Carlo
simulations to model the interaction of charged particles and photons from
astrophysical sources in the upper Martian atmosphere and discuss its
implications on atmospheric loss. Our calculations suggest that the passage of
the solar system though dense interstellar clouds is the most significant
contributor to atmospheric loss among the sources considered here.


title: Search for $XYZ$ states in $\Upsilon(1S)$ inclusive decays

abstract:
  The branching fractions of the $\Upsilon(1S)$ inclusive decays into final
states with a $J/\psi$ or a $\psi(2S)$ are measured with improved precision to
be $\BR(\Upsilon(1S)\to J/\psi + {\rm anything})=(5.25\pm
0.13(\mathrm{stat.})\pm 0.25(\mathrm{syst.}))\times 10^{-4}$ and
$\BR(\Upsilon(1S)\to \psi(2S) + {\rm anything})=(1.23\pm
0.17(\mathrm{stat.})\pm 0.11(\mathrm{syst.}))\times 10^{-4}$. The first search
for $\Upsilon(1S)$ decays into $XYZ$ states that decay into a $J/\psi$ or a
$\psi(2S)$ plus one or two charged tracks yields no significant signals for
$XYZ$ states in any of the examined decay modes, and upper limits on their
production rates in $\Upsilon(1S)$ inclusive decays are determined.


title:
Gauge $B-L$ Model of Radiative Neutrino Mass with Multipartite Dark
  Matter

abstract:
  We propose an extension of the standard model of quarks and leptons to
include gauge $B-L$ symmetry with an exotic array of neutral fermion singlets
for anomaly cancellation. With the addition of suitable scalars also
transforming under $U(1)_{B-L}$, this becomes a model of radiative seesaw
neutrino mass with possible multipartite dark matter. If leptoquark fermions
are added, necessarily also transforming under $B-L$, the diphoton excess at
750 GeV, recently observed at the Large Hadron Collider, may also be explained.


title: The Quantum Computer Puzzle (Expanded Version)

abstract:
  Quantum computers are hypothetical devices, based on quantum physics, that
would enable us to perform certain computations hundreds of orders of magnitude
faster than digital computers. This feature is coined as "quantum supremacy"
and one aspect or another of such quantum computational supremacy might be
brought about in experiments in the near future: by implementing quantum
error-correction, systems of non-interacting bosons, exotic new phases of
matter called anyons, quantum annealing, or in various other ways.
  A main concern regarding the feasibility of quantum computers is that quantum
systems are inherently noisy: we cannot accurately control them, and we cannot
accurately describe them. We will describe an optimistic hypothesis of quantum
noise that would allow quantum computing and a pessimistic hypothesis that
wouldn't. The quantum computer puzzle is deciding between these two hypotheses.
  Here is a brief summary of the author's pessimistic point of view as
explained in the paper: understanding quantum computers in the presence of
noise requires consideration of behavior at different scales. In the small
scale, standard models of noise from the mid-90s are suitable, and quantum
evolutions and states described by them manifest a very low-level computational
power. This small-scale behavior has far-reaching consequences for the behavior
of noisy quantum systems at larger scales. On the one hand, it does not allow
reaching the starting points for quantum fault tolerance and quantum supremacy,
making them both impossible at all scales. On the other hand, it leads to novel
implicit ways for modeling noise at larger scales and to various predictions on
the behavior of noisy quantum systems.


title: Newton law in covariant unimodular $F(R)$ gravity

abstract:
  We propose a covariant ghost-free unimodular $F(R)$ gravity theory, which
contains a three-form field and study its structure using the analogy of the
proposed theory with a quantum system which describes a charged particle in
uniform magnetic field. Newton's law in non-covariant unimodular $F(R)$ gravity
as well as in unimodular Einstein gravity is derived and it is shown to be just
the same as in General Relativity. The derivation of Newton's law in covariant
unimodular $F(R)$ gravity shows that it is modified precisely in the same way
as in the ordinary $F(R)$ theory. We also demonstrate that the cosmology of a
Friedmann-Robertson-Walker background, is equivalent in the non-covariant and
covariant formulations of unimodular $F(R)$ theory.


title:
Magnetic-field-induced relativistic properties in type-I and type-II
  Weyl semimetals

abstract:
  We investigate Weyl semimetals with tilted conical bands in a magnetic field.
Even when the cones are overtilted (type-II Weyl semimetal), Landau-level
quantization can be possible as long as the magnetic field is oriented close to
the tilt direction. Most saliently, the tilt can be described within the
relativistic framework of Lorentz transformations that give rise to a rich
spectrum, displaying new transitions beyond the usual dipolar ones in the
optical conductivity. We identify particular features in the latter that allow
one to distinguish between semimetals of different types.


title:
On a family of KP multi-line solitons associated to rational
  degenerations of real hyperelliptic curves and to the finite non-periodic
  Toda hierarchy

abstract:
  We classify the soliton data in the totally non--negative part of Gr(k,n)
which may be associated to algebraic-geometric data on certain rational
degenerations of regular hyperelliptic M-curves. Such degenerate rational curve
G is a desingularization of that constructed in Abenda-Grinevich
(arXiv:1506.00563) for soliton data in the totally positive part of Gr(n-1,n)
and the KP wavefunctions are the same in such case. G is also the curve
constructed in the paper for soliton data in the totally positive part of
Gr(1,n). For any such G and for any fixed k between 2 and (n-2), we show that
k-compatible soliton data correspond to a family of KP multi-line solitons
(T-hyperelliptic) which parametrize soliton data in an (n-1)--dimensional
variety of the totally positive part of the Grassmannian Gr(k,n). We explicitly
characterize T-hyperelliptic solitons from the algebraic-point of view.
T-hyperelliptic solitons are also connected to the solutions of the finite
non-periodic Toda hierarchy because the tau function is the same for both
systems. We investigate such relation from the algebraic point of view and
compare the two spectral problems. In particular, the vacuum KP divisor and the
Toda divisor coincide, while k--compatible divisors may be recursively
constructed using known recursions for the Toda system. Finally, we also
explain how KP divisors change under the space--time transformation which
induces a duality tranformation from soliton data in Gr(k,n) to soliton data in
Gr(n-k,n) and compare the action of such transformation both for the KP and the
Toda systems.


title:
Quantum Field Theory of Interacting Dark Matter/Dark Energy: Dark
  Monodromies

abstract:
  We discuss how to formulate a quantum field theory of dark energy interacting
with dark matter. We show that the proposals based on the assumption that dark
matter is made up of heavy particles with masses which are very sensitive to
the value of dark energy are strongly constrained. Quintessence-generated long
range forces and radiative stability of the quintessence potential require that
such dark matter and dark energy are completely decoupled. However, if dark
energy and a fraction of dark matter are very light axions, they can have
significant mixings which are radiatively stable and perfectly consistent with
quantum field theory. Such models can naturally occur in multi-axion
realizations of monodromies. The mixings yield interesting signatures which are
observable and are within current cosmological limits but could be constrained
further by future observations.


title:
Nucleon to $\Delta$ transition form factors and empirical transverse
  charge densities

abstract:
  We investigate the nucleon to $\Delta$ transition form factors in a soft-wall
AdS/QCD model and a light-front quark-diquark model inspired by AdS/QCD. From
the transition form factors we evaluate the transition charge densities which
influences the nucleon to $\Delta$ excitation. Here we consider both the
unpolarized and the transversely polarized cases. The AdS/QCD predictions are
compared with available experimental data and with the results of the global
parameterization, MAID2007.


title:
Blackbox: A procedure for parallel optimization of expensive black-box
  functions

abstract:
  This note provides a description of a procedure that is designed to
efficiently optimize expensive black-box functions. It uses the response
surface methodology by incorporating radial basis functions as the response
model. A simple method based on a Latin hypercube is used for initial sampling.
A modified version of CORS algorithm with space rescaling is used for the
subsequent sampling. The procedure is able to scale on multicore processors by
performing multiple function evaluations in parallel. The source code of the
procedure is written in Python.


title:
Time evolution of decay for purely absorptive potentials: The effect of
  spectral singularities

abstract:
  We consider an analytical approach that involves the complex poles of the
propagator to investigate the effect due to the lack of time reversal
invariance on the time evolution of decay for purely absorptive potentials. We
find that the choice of the initial state may change the exponential decaying
regime into a nonexponential oscillatory behavior at time scales of the order
of a lifetime of the system. We illustrate this effect for a spectral
singularity corresponding to a purely imaginary delta-shell potential.


title:
Stationary and moving breathers in (2+1)-dimensional O(3) nonlinear
  $\sigma$-model

abstract:
  The formation and evolution of stationary and moving breather solutions in
(2+1)-dimensional O(3) nonlinear $\sigma$-model are investigated. The
analytical form of oscillating solutions for (2+1)-dimensional sine-Gordon
equation, which evolve to periodic (breather) radially symmetric solutions is
determined. On the basis of the found solutions by adding the rotations to the
A3-field vector in isotopic space of S^2, the solutions for the O(3) nonlinear
$\sigma$-model are obtained. By numerical study of the solutions dynamics their
stability in a stationary and a moving state for quite a long time (45000
cycles), although in the presence of weak radiation is shown.


title:
The effect of detector nonlinearity on WFIRST PSF profiles for weak
  gravitational lensing measurements

abstract:
  Weak gravitational lensing (WL) is one of the most powerful techniques to
learn about the dark sector of the universe. To extract the WL signal from
astronomical observations, galaxy shapes must be measured and corrected for the
point spread function (PSF) of the imaging system with extreme accuracy. Future
WL missions (such as the Wide-Field Infrared Survey Telescope, WFIRST) will use
a family of hybrid nearinfrared CMOS detectors (HAWAII-4RG) that are untested
for accurate WL measurements. Like all image sensors, these devices are subject
to conversion gain nonlinearities (voltage response to collected photo-charge)
that bias the shape and size of bright objects such as reference stars that are
used in PSF determination. We study this type of detector nonlinearity (NL) and
show how to derive requirements on it from WFIRST PSF size and ellipticity
requirements. We simulate the PSF optical profiles expected for WFIRST and
measure the fractional error in the PSF size and the absolute error in the PSF
ellipticity as a function of star magnitude and the NL model. For our nominal
NL model (a quadratic correction), we find that, uncalibrated, NL can induce an
error of 0.01 (fractional size) and 0.00175 (absolute ellipticity error) in the
H158 bandpass for the brightest unsaturated stars in WFIRST. In addition, our
simulations show that to limit the bias of the size and ellipticity errors in
the H158 band to approximately 10% of the estimated WFIRST error budget, the
parameter of our quadratic NL model must be calibrated to about 1% and 2.4%,
respectively. We present a fitting formula that can be used to estimate WFIRST
detector NL requirements once a true PSF error budget is established.


title:
A solution with free boundary for non-Newtonian fluids with
  Drucker-Prager plasticity criterion

abstract:
  We study a free boundary problem which is motivated by a particular case of
the flow of a non-Newtonian fluid, with a pressure depending yield stress given
by a Drucker-Prager plasticity criterion. We focus on the steady case and
reformulate the equation as a variational problem. The resulting energy has a
term with linear growth while we study the problem in an unbounded domain. We
derive an Euler-Lagrange equation and prove a comparison principle. We are then
able to construct a subsolution and a supersolution which quantify the natural
and expected properties of the solution; in particular they show that the
solution has in fact compact support, the boundary of which is the free
boundary.
  The model describes the flow of a non-Newtonian material on an inclined plane
with walls, driven by gravity. We show that there is a critical angle for a
non-zero solution to exist. Finally, using the sub/supersolutions we give
estimates of the free boundary.


title: Monadic second order logic as the model companion of temporal logic

abstract:
  The main focus of this paper is on bisimulation-invariant MSO, and more
particularly on giving a novel model-theoretic approach to it. In model theory,
a model companion of a theory is a first-order description of the class of
models in which all potentially solvable systems of equations and non-equations
have solutions. We show that bisimulation-invariant MSO on trees gives the
model companion for a new temporal logic, "fair CTL", an enrichment of CTL with
local fairness constraints. To achieve this, we give a completeness proof for
the logic fair CTL which combines tableaux and Stone duality, and a fair CTL
encoding of the automata for the modal {\mu}-calculus. Moreover, we also show
that MSO on binary trees is the model companion of binary deterministic fair
CTL.


title: The Completeness Problem for Modal Logic

abstract:
  We introduce the completeness problem for Modal Logic and examine its
complexity. For a definition of completeness for formulas, given a formula of a
modal logic, the completeness problem asks whether the formula is complete for
that logic. We discover that completeness and validity have the same complexity
--- with certain exceptions for which there are, in general, no complete
formulas. To prove upper bounds, we present a non-deterministic polynomial-time
procedure with an oracle from PSPACE that combines tableaux and a test for
bisimulation, and determines whether a formula is complete.


title: Quantum melting of two-component Rydberg crystals

abstract:
  We investigate the quantum melting of one dimensional crystals that are
realized in an atomic lattice in which ground state atoms are laser excited to
two Rydberg states. We focus on a regime where both, intra- and inter-state
density-density interactions as well as coherent exchange interactions
contribute. We determine stable crystalline phases in the classical limit and
explore their melting under quantum fluctuations introduced by the excitation
laser as well as two-body exchange. We find that within a specific parameter
range quantum fluctuations introduced by the laser can give rise to a devil's
staircase structure which one might associate with transitions in the classical
limit. The melting through exchange interactions is shown to also proceed in a
step-like fashion, in case of small crystals, due to the proliferation of
Rydberg spinwaves.


title: Trace-free Korn inequalities in Orlicz spaces

abstract:
  Necessary and sufficient conditions are exhibited for a Korn type inequality
to hold between (possibly different) Orlicz norms of the gradient of
vector-valued functions and of the deviatoric part of their symmetric
gradients. As a byproduct of our approach, a positive answer is given to the
question of the necessity of the same sufficient conditions in related Korn
type inequalities for the full symmetric gradient, for negative Orlicz-Sobolev
norms, and for the gradient of the Bogovskii operator.


title:
Hybridization of photon-plasmon modes in metal-coated microtubular
  cavities

abstract:
  The coupling of resonant light and surface plasmons in metal layer coated
optical microcavities results in the formation of hybrid photon-plasmon modes.
Here, we comprehensively investigate the hybridization mechanism of
photon-plasmon modes based on opto-plasmonic microtubular cavities. By changing
the cavity structure and the metal layer thickness, weakly, moderately and
strongly hybridized resonant modes are demonstrated depending on the
photon-plasmon coupling strength. An effective potential approach is applied to
illustrate the hybridization of photon-plasmon modes relying on the competition
between light confinement by the cavity wall and the potential barrier
introduced by the metal layer. Our work reveals the basic physical mechanisms
for the generation of hybrid modes in metal-coated whispering-gallery-mode
microcavities, and is of importance for the study of enhanced light-matter
interactions and potential sensing applications.


title:
Modifications to Cosmological Power Spectra from Scalar-Tensor
  Entanglement and their Observational Consequences

abstract:
  We consider the effects of entanglement in the initial quantum state of
scalar and tensor fluctuations during inflation. We allow the gauge-invariant
scalar and tensor fluctuations to be entangled in the initial state and compute
modifications to the various cosmological power spectra. We compute the angular
power spectra ($C_l$'s) for some specific cases of our entangled state and
discuss what signals one might expect to find in CMB data. This entanglement
also can break rotational invariance, allowing for the possibility that some of
the large scale anomalies in the CMB power spectrum might be explained by this
mechanism.


title:
Metastability of non-reversible random walks in a potential field, the
  Eyring-Kramers transition rate formula

abstract:
  We consider non-reversible random walks evolving on a potential field in a
bounded domain of $\mathbb{R}^d$. We describe the complete metastable behavior
of the random walk among the landscape of valleys, and we derive the
Eyring-Kramers formula for the mean transition time from a metastable set to a
stable set.


title:
A Novel Approach for Imputation of Missing Attribute Values for
  Efficient Mining of Medical Datasets - Class Based Cluster Approach

abstract:
  Missing attribute values are quite common in the datasets available in the
literature. Missing values are also possible because all attributes values may
not be recorded and hence unavailable due to several practical reasons. For all
these one must fix missing attribute vales if the analysis has to be done.
Imputation is the first step in analyzing medical datasets. Hence this has
achieved significant contribution from several medical domain researchers.
Several data mining researchers have proposed various methods and approaches to
impute missing values. However very few of them concentrate on dimensionality
reduction. In this paper, we discuss a novel imputation framework for missing
values imputation. Our approach of filling missing values is rooted on class
based clustering approach and essentially aims at medical records
dimensionality reduction. We use these dimensionality records for carrying
prediction and classification analysis. A case study is discussed which shows
how imputation is performed using proposed method.


title: Minimax Rates for Estimating the Dimension of a Manifold

abstract:
  Many algorithms in machine learning and computational geometry require, as
input, the intrinsic dimension of the manifold that supports the probability
distribution of the data. This parameter is rarely known and therefore has to
be estimated. We characterize the statistical difficulty of this problem by
deriving upper and lower bounds on the minimax rate for estimating the
dimension. First, we consider the problem of testing the hypothesis that the
support of the data-generating probability distribution is a well-behaved
manifold of intrinsic dimension $d_1$ versus the alternative that it is of
dimension $d_2$, with $d_{1}<d_{2}$. With an i.i.d. sample of size $n$, we
provide an upper bound on the probability of choosing the wrong dimension of
$O\left( n^{-\left(d_{2}/d_{1}-1-\epsilon\right)n} \right)$, where $\epsilon$
is an arbitrarily small positive number. The proof is based on bounding the
length of the traveling salesman path through the data points. We also
demonstrate a lower bound of $\Omega \left( n^{-(2d_{2}-2d_{1}+\epsilon)n}
\right)$, by applying Le Cam's lemma with a specific set of $d_{1}$-dimensional
probability distributions. We then extend these results to get minimax rates
for estimating the dimension of well-behaved manifolds. We obtain an upper
bound of order $O \left( n^{-(\frac{1}{m-1}-\epsilon)n} \right)$ and a lower
bound of order $\Omega \left( n^{-(2+\epsilon)n} \right)$, where $m$ is the
embedding dimension.


title:
Covalent Functionalization and Passivation of Exfoliated Black
  Phosphorus via Aryl Diazonium Chemistry

abstract:
  Functionalization of atomically thin nanomaterials enables the tailoring of
their chemical, optical, and electronic properties. Exfoliated black
phosphorus, a layered two-dimensional semiconductor exhibiting favorable charge
carrier mobility, tunable bandgap, and highly anisotropic properties, is
chemically reactive and degrades rapidly in ambient conditions. In contrast,
here we show that covalent aryl diazonium functionalization suppresses the
chemical degradation of exfoliated black phosphorus even following weeks of
ambient exposure. This chemical modification scheme spontaneously forms
phosphorus-carbon bonds, has a reaction rate sensitive to the aryl diazonium
substituent, and alters the electronic properties of exfoliated black
phosphorus, ultimately yielding a strong, tunable p-type doping that
simultaneously improves field-effect transistor mobility and on/off current
ratio. This chemical functionalization pathway controllably modifies the
properties of exfoliated black phosphorus, thus improving its prospects for
nanoelectronic applications.


title:
Transition from direct to sequential two-proton decay in $s$-$d$ shell
  nuclei

abstract:
  Transitions among different mechanisms of two-proton decay are studied in
general. The introduced improved direct-decay model generalizes the
semi-analytical models used before and provides flawless phenomenological
description of three-body correlations in $2p$ decays. This is demonstrated by
examples of the low-lying $^{16}$Ne state decays. Different forms of transition
dynamic are shown to be highly probable beyond the proton dripline for the
$s$-$d$ shell nuclei. It is demonstrated that transition dynamic of $2p$
emitters can provide means for extraction of a width of the ground-state
resonance of a core+$p$ subsystem of the core+$2p$ system. Practical
applicability of the method is demonstrated by properties of the $^{14}$F
ground state derived from the $^{15}\mbox{Ne}\rightarrow
^{\,13\!\!}\mbox{O}+2p$ decay data and of the $^{29}$Cl ground state derived
from the $^{30}\mbox{Ar}\rightarrow ^{\,28\!\!}\mbox{S}+2p$ decay data.


title: Deep Deformation Network for Object Landmark Localization

abstract:
  We propose a novel cascaded framework, namely deep deformation network (DDN),
for localizing landmarks in non-rigid objects. The hallmarks of DDN are its
incorporation of geometric constraints within a convolutional neural network
(CNN) framework, ease and efficiency of training, as well as generality of
application. A novel shape basis network (SBN) forms the first stage of the
cascade, whereby landmarks are initialized by combining the benefits of CNN
features and a learned shape basis to reduce the complexity of the highly
nonlinear pose manifold. In the second stage, a point transformer network (PTN)
estimates local deformation parameterized as thin-plate spline transformation
for a finer refinement. Our framework does not incorporate either handcrafted
features or part connectivity, which enables an end-to-end shape prediction
pipeline during both training and testing. In contrast to prior cascaded
networks for landmark localization that learn a mapping from feature space to
landmark locations, we demonstrate that the regularization induced through
geometric priors in the DDN makes it easier to train, yet produces superior
results. The efficacy and generality of the architecture is demonstrated
through state-of-the-art performances on several benchmarks for multiple tasks
such as facial landmark localization, human body pose estimation and bird part
localization.


title:
Anisotropic transport at the LaAlO3/SrTiO3 interface explained by
  microscopic imaging of channel-flow over SrTiO3 domains

abstract:
  Oxide interfaces, including the LaAlO3/SrTiO3 interface, have been a subject
of intense interest for over a decade due to their rich physics and potential
as low dimensional nanoelectronic systems. The field has reached the stage
where efforts are invested in developing devices. It is critical now to
understand the functionalities and limitations of such devices. Recent scanning
probe measurements of the LaAlO3/SrTiO3 interface have revealed locally
enhanced current flow and accumulation of charge along channels related to
SrTiO3 structural domains. These observations raised a key question regarding
the role these modulations play in the macroscopic properties of devices. Here
we show that the microscopic picture, mapped by scanning superconducting
quantum interference device, accounts for a substantial part of the
macroscopically measured transport anisotropy. We compared local flux data with
transport values, measured simultaneously, over various SrTiO3 domain
configurations. We show a clear relation between maps of local current density
over specific domain configurations and the measured anisotropy for the same
device. The domains divert the direction of current flow, resulting in a
direction dependent resistance. We also show that the modulation can be
significant and that in some cases up to 95% of the current is modulated over
the channels. The orientation and distribution of the SrTiO3 structural domains
change between different cooldowns of the same device or when electric fields
are applied, affecting the device behavior. Our results, highlight the
importance of substrate physics, and in particular, the role of structural
domains, in controlling electronic properties of LaAlO3/SrTiO3 devices.
Further, these results point to new research directions, exploiting the STO
domains ability to divert or even carry current.


title:
Klein-four connections and the Casson invariant for non-trivial
  admissible $U(2)$ bundles

abstract:
  Given a rank 2 hermitian bundle over a 3-manifold that is non-trivial
admissible in the sense of Floer, one defines its Casson invariant as half the
signed count of its projectively flat connections, suitably perturbed. We show
that the 2-divisibility of this integer invariant is controlled in part by a
formula involving the mod 2 cohomology ring of the 3-manifold. This formula
counts flat connections on the induced adjoint bundle with Klein-four holonomy.


title: Permanence and Stability of a Kill the Winner Model in Marine Ecology

abstract:
  We focus on the long term dynamics of "killing the winner" Lotka-Volterra
models of marine communities consisting of bacteria, virus, and zooplankton.
Under suitable conditions, it is shown that there is a unique equilibrium with
all populations present which is stable, the system is permanent, and the
limiting behavior of its solutions is strongly constrained.


title: A Solution to Time-Varying Markov Decision Processes

abstract:
  We consider a decision-making problem where the environment varies both in
space and time. Such problems arise naturally when considering e.g., the
navigation of an underwater robot amidst ocean currents or the navigation of an
aerial vehicle in wind. To model such spatiotemporal variation, we extend the
standard Markov Decision Process (MDP) to a new framework called the
Time-Varying Markov Decision Process (TVMDP). The TVMDP has a time-varying
state transition model and transforms the standard MDP that considers only
immediate and static uncertainty descriptions of state transitions, to a
framework that is able to adapt to future time-varying transition dynamics over
some horizon. We show how to solve a TVMDP via a redesign of the MDP value
propagation mechanisms by incorporating the introduced dynamics along the
temporal dimension. We validate our framework in a marine robotics navigation
setting using spatiotemporal ocean data and show that it outperforms prior
efforts.


title: Estimating an Inverse Gamma distribution

abstract:
  In this paper we introduce five different algorithms based on method of
moments, maximum likelihood and full Bayesian estimation for learning the
parameters of the Inverse Gamma distribution. We also provide an expression for
the KL divergence for Inverse Gamma distributions which allows us to quantify
the estimation accuracy of each of the algorithms. All the presented algorithms
are novel. The most relevant novelties include the first conjugate prior for
the Inverse Gamma shape parameter which allows analytical Bayesian inference,
and two very fast algorithms, a maximum likelihood and a Bayesian one, both
based on likelihood approximation. In order to compute expectations under the
proposed distributions we use the Laplace approximation. The introduction of
these novel Bayesian estimators opens the possibility of including Inverse
Gamma distributions into more complex Bayesian structures, e.g. variational
Bayesian mixture models. The algorithms introduced in this paper are
computationally compared using synthetic data and interesting relationships
between the maximum likelihood and the Bayesian approaches are derived.


title:
Implicit large-eddy simulation of compressible flows using the Interior
  Embedded Discontinuous Galerkin method

abstract:
  We present a high-order implicit large-eddy simulation (ILES) approach for
simulating transitional turbulent flows. The approach consists of an Interior
Embedded Discontinuous Galerkin (IEDG) method for the discretization of the
compressible Navier-Stokes equations and a parallel preconditioned Newton-GMRES
solver for the resulting nonlinear system of equations. The IEDG method arises
from the marriage of the Embedded Discontinuous Galerkin (EDG) method and the
Hybridizable Discontinuous Galerkin (HDG) method. As such, the IEDG method
inherits the advantages of both the EDG method and the HDG method to make
itself well-suited for turbulence simulations. We propose a minimal residual
Newton algorithm for solving the nonlinear system arising from the IEDG
discretization of the Navier-Stokes equations. The preconditioned GMRES
algorithm is based on a restricted additive Schwarz (RAS) preconditioner in
conjunction with a block incomplete LU factorization at the subdomain level.
The proposed approach is applied to the ILES of transitional turbulent flows
over a NACA 65-(18)10 compressor cascade at Reynolds number 250,000 in both
design and off-design conditions. The high-order ILES results show good
agreement with a subgrid-scale LES model discretized with a second-order finite
volume code while using significantly less degrees of freedom. This work shows
that high-order accuracy is key for predicting transitional turbulent flows
without a SGS model.

categories: physics.flu-dyn cs.CE math.NA physics.comp-ph


title:
An Information Theoretic Framework For Designing Information Elicitation
  Mechanisms That Reward Truth-telling

abstract:
  In the setting where information cannot be verified, we propose a simple yet
powerful information theoretical framework---the Mutual Information
Paradigm---for information elicitation mechanisms. Our framework pays every
agent a measure of mutual information between her signal and a peer's signal.
We require that the mutual information measurement has the key property that
any "data processing" on the two random variables will decrease the mutual
information between them. We identify such information measures that generalize
Shannon mutual information.
  Our Mutual Information Paradigm overcomes the two main challenges in
information elicitation without verification: (1) how to incentivize effort and
avoid agents colluding to report random or identical responses (2) how to
motivate agents who believe they are in the minority to report truthfully.
  Aided by the information measures we found, (1) we use the paradigm to design
a family of novel mechanisms where truth-telling is a dominant strategy and any
other strategy will decrease every agent's expected payment (in the
multi-question, detail free, minimal setting where the number of questions is
large); (2) we show the versatility of our framework by providing a unified
theoretical understanding of existing mechanisms---Peer Prediction [Miller
2005], Bayesian Truth Serum [Prelec 2004], and Dasgupta and Ghosh [2013]---by
mapping them into our framework such that theoretical results of those existing
mechanisms can be reconstructed easily.
  We also give an impossibility result which illustrates, in a certain sense,
the the optimality of our framework.


title:
Photophoresis on particles hotter/colder than the ambient gas in the
  free molecular flow

abstract:
  Aerosol particles experience significant photophoretic forces at low
pressure. Previous work assumed the average particle temperature to be very
close to the gas temperature. This might not always be the case. If the
particle temperature or the thermal radiation field differs significantly from
the gas temperature (optically thin gases), given approximations overestimate
the photophoretic force by an order of magnitude on average with maximum errors
up to more than three magnitudes. We therefore developed a new general
approximation which on average only differs by 1 % from the true value.


title:
Universal space-time scaling symmetry in the dynamics of bosons across a
  quantum phase transition

abstract:
  The dynamics of many-body systems spanning condensed matter, cosmology, and
beyond is hypothesized to be universal when the systems cross continuous phase
transitions. The universal dynamics is expected to satisfy a scaling symmetry
of space and time with the crossing rate, inspired by the Kibble-Zurek
mechanism. We test this symmetry based on Bose condensates in a shaken optical
lattice. Shaking the lattice drives condensates across an effectively
ferromagnetic quantum phase transition. After crossing the critical point, the
condensates manifest delayed growth of spin fluctuations and develop
anti-ferromagnetic spatial correlations resulting from sub-Poisson generation
of topological defects. The characteristic times and lengths scale as
power-laws of the crossing rate, yielding the temporal exponent 0.50(2) and the
spatial exponent 0.26(2), consistent with theory. Furthermore, the fluctuations
and correlations are invariant in scaled space-time coordinates, in support of
the scaling symmetry of quantum critical dynamics.


title: On Borel semifilters

abstract:
  Building on work of van Engelen and van Mill, we show that a zero-dimensional
Borel space is homeomorphic to a semifilter if and only if it is homogeneous
and not locally compact. Under $\mathbf{\Sigma}^1_1$-Determinacy, this result
extends to all analytic and coanalytic spaces.


title: A note on multiply wound BPS Wilson loops in ABJM

abstract:
  We consider BPS Wilson loops in planar ABJM theory, wound multiple times
around the great circle. We compute the expectation value of the 1/6-BPS and
1/2-BPS Wilson loops to three- and two-loop order in perturbation theory,
respectively, dealing with the combinatorics of multiple winding via recursive
relations. For the 1/6-BPS Wilson loop we perform the computation at generic
framing and at framing 1 we find agreement with the localization result. For
the 1/2-BPS Wilson loop we compute the expectation value at trivial framing and
by comparison with the matrix model expression we extract the framing
dependence of the fermion diagrams.


title: On Selmer groups and factoring $p$-adic $L$-functions

abstract:
  Samit Dasgupta has proved a formula factoring a certain restriction of a
3-variable Rankin-Selberg $p$-adic $L$-function as a product of a 2-variable
$p$-adic $L$-function related to the adjoint representation of a Hida family
and a Kubota-Leopoldt $p$-adic $L$-function. We prove a result involving Selmer
groups that along with Dasgupta's result is consistent with the main
conjectures associated to the 4-dimensional representation (to which the
3-variable $p$-adic $L$-function is associated), the $3$-dimensional
representation (to which the $2$-variable $p$-adic $L$-function is associated)
and the $1$-dimensional representation (to which the Kubota-Leopoldt $p$-adic
$L$-function is associated). Under certain additional hypotheses, we indicate
how one can use work of Urban to deduce main conjectures for the
$3$-dimensional representation and the $4$-dimensional representation. One key
technical input to our methods is studying the behavior of Selmer groups under
specialization.


title:
Mechanism of stimulated Hawking radiation in a laboratory Bose-Einstein
  condensate

abstract:
  We model a sonic black hole analog in a quasi one-dimensional Bose-Einstein
condensate, using a Gross-Pitaevskii equation matching the configuration of a
recent experiment by Steinhauer [Nat. Phys. 10, 864 (2014)]. The model agrees
well with important features of the experimental observations, demonstrating
their hydrodynamic nature. We find that a zero-frequency bow wave is generated
at the inner (white hole) horizon, which grows in proportion to the square of
the background condensate density. The relative motion of the black and white
hole horizons produces a Doppler shift of the bow wave at the black hole, where
it stimulates the emission of monochromatic Hawking radiation. The mechanism is
confirmed using temporal and spatial windowed Fourier spectra of the
condensate. Mean field behavior similar to that in the experiment can thus be
fully explained without the presence of self-amplifying Hawking radiation.


title: On Optimal Retirement (How to Retire Early)

abstract:
  We pose an optimal control problem arising in a perhaps new model for
retirement investing. Given a control function $f$ and our current net worth as
$X(t)$ for any $t$, we invest an amount $f(X(t))$ in the market. We need a
fortune of $M$ "superdollars" to retire and want to retire as early as
possible. We model our change in net worth over each infinitesimal time
interval by the Ito process $dX(t)= (1+f(X(t))dt+ f(X(t))dW(t)$. We show how to
choose the optimal $f=f_0$ and show that the choice of $f_0$ is optimal among
all nonanticipative investment strategies, not just among Markovian ones.


title: Online Machine Learning Techniques for Predicting Operator Performance

abstract:
  This thesis explores a number of online machine learning algorithms. From a
theoret- ical perspective, it assesses their employability for a particular
function approximation problem where the analytical models fall short.
Furthermore, it discusses the applica- tion of theoretically suitable learning
algorithms to the function approximation problem at hand through an efficient
implementation that exploits various computational and mathematical shortcuts.
Finally, this thesis work evaluates the implemented learning algorithms
according to various evaluation criteria through rigorous testing.


title:
Comparing Kalman Filters and Observers for Power System Dynamic State
  Estimation with Model Uncertainty and Malicious Cyber Attacks

abstract:
  Kalman filters and observers are two main classes of dynamic state estimation
(DSE) routines. Power system DSE has been implemented by various Kalman
filters, such as the extended Kalman filter (EKF) and the unscented Kalman
filter (UKF). In this paper, we discuss two challenges for an effective power
system DSE: (a) model uncertainty and (b) potential cyber attacks. To address
this, the cubature Kalman filter (CKF) and a nonlinear observer are introduced
and implemented. Various Kalman filters and the observer are then tested on the
16-machine, 68-bus system given realistic scenarios under model uncertainty and
different types of cyber attacks against synchrophasor measurements. It is
shown that CKF and the observer are more robust to model uncertainty and cyber
attacks than their counterparts. Based on the tests, a thorough qualitative
comparison is also performed for Kalman filter routines and observers.