title:
Open Packet Processor: a programmable architecture for wire speed
  platform-independent stateful in-network processing

abstract:
  This paper aims at contributing to the ongoing debate on how to bring
programmability of stateful packet processing tasks inside the network
switches, while retaining platform independency. Our proposed approach, named
"Open Packet Processor" (OPP), shows the viability (via an hardware prototype
relying on commodity HW technologies and operating in a strictly bounded number
of clock cycles) of eXtended Finite State Machines (XFSM) as low-level data
plane programming abstraction. With the help of examples, including a token
bucket and a C4.5 traffic classifier based on a binary tree, we show the
ability of OPP to support stateful operation and flow-level feature tracking.
Platform independence is accomplished by decoupling the implementation of
hardware primitives (registries, conditions, update instructions, forwarding
actions, matching facilities) from their usage by an application formally
described via an abstract XFSM. We finally discuss limitations and extensions.


title: An inertial lower bound for the chromatic number of a graph

abstract:
  Let $\chi(G$) and $\chi_f(G)$ denote the chromatic and fractional chromatic
numbers of a graph $G$, and let $(n^+ , n^0 , n^-)$ denote the inertia of $G$.
We prove that:
  \[ 1 + \max\left(\frac{n^+}{n^-} , \frac{n^-}{n^+}\right) \le \chi(G) \mbox{
and conjecture that } 1 + \max\left(\frac{n^+}{n^-} , \frac{n^-}{n^+}\right)
\le \chi_f(G) \]
  We investigate extremal graphs for these bounds and demonstrate that this
inertial bound is not a lower bound for the vector chromatic number. We
conclude with a discussion of asymmetry between $n^+$ and $n^-$, including some
Nordhaus-Gaddum bounds for inertia.


title:
Quantum Cosmology in $(1+1)$-dimensional Ho\v{r}ava-Lifshitz theory of
  gravity

abstract:
  In a recent paper [Phys. Rev. D 92:084012, 2015], the author studied the
classical $(1+1)$-dimensional Friedmann-Robertson-Walker (FRW) universe filled
with a perfect fluid in Ho\v{r}ava-Lifshitz (HL) theory of gravity. This theory
is dynamical due to the anisotropic scaling of space and time. It also
resembles the Jackiw-Teitelboim model, in which a dilatonic degree of freedom
is necessary for dynamics. In this paper, I will give one step further in the
understanding of (1+1)-dimensional HL cosmology by means of the quantization of
the FRW universe filled with a perfect fluid with equation of state (EoS)
$p=w\rho$. The fluid will be introduced in the model via Schutz formalism and
Dirac's algorithm will be used for quantization. It will be shown that the
Schr\"odinger equation for the wave function of the universe has the following
properties: for $w=1$ (radiation fluid), the characteristic potential will be
exponential, resembling Liouville quantum mechanics; for $w\neq 1$, a
characteristic inverse square potential appears in addition to a regular
polynomial which depends on the EoS. Explict solutions for a few cases of
interesting will be found and the expectation value of the scale factor will be
calculated. As in usual quantum cosmology, it will be shown that the quantum
theory smooth out the big-bang singularity, but the classical behavior of the
universe is recovered in the low-energy limit.


title:
Low temperature-semiconductor band gap thermal shifts: T^4 shifts from
  ordinary acoustic and T^2 from piezoacoustic coupling

abstract:
  At low temperature T, the experimental gap of silicon decreases as
E_g(T)=E_g(0)-AT^4. The main reason is electron-phonon renormalization. The
physics behind the T^4-power law is more complex than has been realized.
Renormalization by intraband scattering requires a careful non-adiabatic
treatment in order to correctly include acoustic phonons and avoid divergences
from piezoacoustic phonon interactions. The result is an unexpected low T term
E_g(0)+A' T^p with positive coefficient A', and power p=4 for non-piezoelectric
materials, and power p=2 for piezoelectric materials. The acoustic phonons in
piezoelectric semiconductors generate a piezoelectric field, modifying the
electron-phonon coupling. However, at higher T, when thermal acoustic phonons
of energy hbar v_s q acquire energies comparable to the electronic intermediate
state (higher than the band-edge state by hbar^2 q^2 /2m*), the low q and
higher q intraband contributions to T^p rapidly cancel, giving little thermal
effect. But there is an additional T-dependence from interband effects of
acoustic phonons. This turns out to have power law T^4 for both
non-piezoelectric and piezoelectric semiconductors. This term can have either
sign, but usually reduces the size of gaps as T increases. It arises after
cancellation of the T^2 terms that appear separately in Debye-Waller and Fan
parts of the acoustic phonon interband renormalization. The cancellation occurs
because of the acoustic sum rule.


title:
Probability distribution built by Prabhakar function. Related Tur\'an
  and Laguerre inequalities

abstract:
  Introducing the discrete probability distribution by means of the Prabhakar
(or the three--parameter Mittag--Leffler) function, we establish explicit
expressions for raw and factorial moments and also general fractional order
moments. Applying an elementary moment inequality we obtain functional upper
bounds for the Tur\'anian difference for Prabhakar function. Finally, a
Laguerre inequality is proved and functional upper bound has been given for
Laguerreian difference for Prabhakar function.


title: On a conjecture of Stein

abstract:
  Stein proposed the following conjecture: if the edge set of $K_{n,n}$ is
partitioned into $n$ sets, each of size $n$, then there is a partial rainbow
matching of size $n-1$. He proved that there is a partial rainbow matching of
size $n(1-\frac{D_n}{n!})$, where $D_n$ is the number of derangements of $[n]$.
This means that there is a partial rainbow matching of size about $(1-
\frac{1}{e})n$. Using a topological version of Hall's theorem we improve this
bound to $\frac{2}{3}n$.


title:
Toward the detection of gravitational waves under non-Gaussian noises
  II. Independent Component Analysis

abstract:
  We introduce a new analysis method to deal with stationary non-Gaussian
noises in gravitational wave detectors in terms of the independent component
analysis. First, we consider the simplest case where the detector outputs are
linear combinations of the inputs, consisting of signals and various noises,
and show that this method may be helpful to increase the signal-to-noise ratio.
Next, we take into account the time delay between the inputs and the outputs.
Finally, we extend our method to nonlinearly correlated noises and show that
our method can identify the coupling coefficients and remove non-Gaussian
noises. Although we focus on gravitational wave data analysis, our methods are
applicable to the detection of any signals under non-Gaussian noises.


title:
Exploring the Dark Universe: constraints on dynamical Dark Energy models
  from CMB, BAO and growth rate measurements

abstract:
  In order to explain the current acceleration of the Universe, the fine tuning
problem of the cosmological constant $\Lambda$ and the cosmic coincidence
problem, different alternative models have been proposed in the literature. We
use the most recent observational data from CMB (Planck 2018 final data
release) and LSS (SDSS, WiggleZ, VIPERS) to constrain dynamical dark energy
(DE) models. The CMB shift parameter, which traditionally has been used to
determine the main cosmological parameters of the standard model $\Lambda CDM$
is employed in addition to data from redshift-space distortions through the
growth parameter $A(z)=f(z)\sigma_{8}(z)$ to constrain the mass variance
$\sigma_{8}$. BAO data is also used to study the history of the cosmological
expansion and the main properties of DE. From the evolution of $q(z)$ we found
a slowdown of acceleration behaviour at low redshifts, and by using the Akaike
and Bayesian Information Criterion (AIC, BIC) we discriminate different models
those that are better suited to the observational data, finding that the
interactive dark energy (IDE) model is the most favoured by observational data,
including information from SNIa and Hz. The analysis shows that the IDE model
is followed closely by EDE and $\Lambda CDM$ models, which in some cases fit
better the observational data with individual probes.


title: CW-resolutions of monomial ideals that are supported on face posets

abstract:
  Given a monomial ideal $I$ with minimal free resolution $\mathcal{F}$
supported in characteristic $p>0$ on a CW-complex $X$ with regular
$2$-skeleton, we construct a CW-complex $Y$ that also supports~$\mathcal{F}$
and such that the face poset $P(Y)$ also supports $\mathcal{F}$ in the sense of
Clark and Tchernev.


title: New Primal-Dual Proximal Algorithm for Distributed Optimization

abstract:
  We consider a network of agents, each with its own private cost consisting of
the sum of two possibly nonsmooth convex functions, one of which is composed
with a linear operator. At every iteration each agent performs local
calculations and can only communicate with its neighbors. The goal is to
minimize the aggregate of the private cost functions and reach a consensus over
a graph. We propose a primal-dual algorithm based on \emph{Asymmetric
Forward-Backward-Adjoint} (AFBA), a new operator splitting technique introduced
recently by two of the authors. Our algorithm includes the method of Chambolle
and Pock as a special case and has linear convergence rate when the cost
functions are piecewise linear-quadratic. We show that our distributed
algorithm is easy to implement without the need to perform matrix inversions or
inner loops. We demonstrate through computational experiments how selecting the
parameter of our algorithm can lead to larger step sizes and yield better
performance.


title: TCPTuner: Congestion Control Your Way

abstract:
  TCPTuner is a TCP (transmission control protocol) congestion control kernel
module and GUI (graphical user interface) for Linux that allows real-time
modification of the congestion control parameters of TCP CUBIC, the current
default algorithm in Linux. Specifically, the tool provides access to alpha,
the rate at which a sender's congestion window grows; beta, the multiplicative
factor to decrease the congestion window on a loss event; as well as CUBIC's
fast convergence and tcp friendliness parameters. Additionally, the interface
provides access to ip-route parameters for the minimum retransmission time and
initial congestion window size. In this paper, we describe the implementation
of TCPTuner and show experimental data of the effects of adjusting congestion
control parameters.


title: LSTM with Working Memory

abstract:
  Previous RNN architectures have largely been superseded by LSTM, or "Long
Short-Term Memory". Since its introduction, there have been many variations on
this simple design. However, it is still widely used and we are not aware of a
gated-RNN architecture that outperforms LSTM in a broad sense while still being
as simple and efficient. In this paper we propose a modified LSTM-like
architecture. Our architecture is still simple and achieves better performance
on the tasks that we tested on. We also introduce a new RNN performance
benchmark that uses the handwritten digits and stresses several important
network capabilities.


title:
Asymptotic cosmological regimes in scalar-torsion gravity with a perfect
  fluid

abstract:
  We consider cosmological dynamics of nonminimally coupled scalar field in the
scalar-torsion gravity in the presence of a hydrodynamical matter. Potential of
the scalar field have been chosen as power-law with negative index, this type
of potentials is usually used in quintessence scenarios. We identify several
asymptotic regimes, including de Sitter, kinetic dominance, kinetic tracker and
tracker solution and study conditions for their existence and stability. We
show that for each combination of coupling constant and potential power index
one of regimes studied in the present paper is stable to the future.


title: Searches for Sterile Neutrinos with the IceCube Detector

abstract:
  The IceCube neutrino telescope at the South Pole has measured the atmospheric
muon neutrino spectrum as a function of zenith angle and energy in the
approximate 320 GeV to 20 TeV range, to search for the oscillation signatures
of light sterile neutrinos. No evidence for anomalous $\nu_\mu$ or
$\bar{\nu}_\mu$ disappearance is observed in either of two independently
developed analyses, each using one year of atmospheric neutrino data. New
exclusion limits are placed on the parameter space of the 3+1 model, in which
muon antineutrinos would experience a strong MSW-resonant oscillation. The
exclusion limits extend to $\mathrm{sin}^2 2\theta_{24} \leq$ 0.02 at $\Delta
m^2 \sim$ 0.3 $\mathrm{eV}^2$ at the 90\% confidence level. The allowed region
from global analysis of appearance experiments, including LSND and MiniBooNE,
is excluded at approximately the 99\% confidence level for the global best fit
value of $|$U$_{e4}|^2$.


title:
Spin orbit alignment for KELT-7b and HAT-P-56b via Doppler tomography
  with TRES

abstract:
  We present Doppler tomographic analyses for the spectroscopic transits of
KELT-7b and HAT-P-56b, two hot-Jupiters orbiting rapidly rotating F-dwarf host
stars. These include analyses of archival TRES observations for KELT-7b, and a
new TRES transit observation of HAT-P-56b. We report spin-orbit aligned
geometries for KELT-7b (2.7 +/- 0.6 deg) and HAT-P-56b (8 +/- 2 deg). The host
stars KELT-7 and HAT-P-56 are among some of the most rapidly rotating
planet-hosting stars known. We examine the tidal re-alignment model for the
evolution of the spin-orbit angle in the context of the spin rates of these
stars. We find no evidence that the rotation rates of KELT-7 and HAT-P-56 have
been modified by star-planet tidal interactions, suggesting that the spin-orbit
angle of systems around these hot stars may represent their primordial
configuration. In fact, KELT-7 and HAT-P-56 are two of three systems in
super-synchronous, spin-orbit aligned states, where the rotation periods of the
host stars are faster than the orbital periods of the planets.


title: Fast Radio Bursts counterparts in the scenario of supergiant pulses

abstract:
  We discuss identification of possible counterparts and persistent sources
related to Fast Radio Bursts (FRBs) in the framework of the model of supergiant
pulses from young neutron stars with large spin-down luminosities. In
particular, we demonstrate that at least some of sources of FRBs can be
observed as ultraluminous X-ray sources (ULXs). At the moment no ULXs are known
to be coincident with localization areas of FRBs. We searched for a correlation
of FRB positions with galaxies in the 2MASS Redshift survey catalogue. Our
analysis produced statistically insignificant overabundance ($p$-value $\approx
4\%$) of galaxies in error boxes of FRBs. In the very near future with even
modestly increased statistics of FRBs and with the help of dedicated X-ray
observations and all-sky X-ray surveys it will be possible to decisively prove
or falsify the supergiant pulses model.


title: Coded Caching for a Large Number Of Users

abstract:
  Information theoretic analysis of a coded caching system is considered, in
which a server with a database of N equal-size files, each F bits long, serves
K users. Each user is assumed to have a local cache that can store M files,
i.e., capacity of MF bits. Proactive caching to user terminals is considered,
in which the caches are filled by the server in advance during the placement
phase, without knowing the user requests. Each user requests a single file, and
all the requests are satisfied simultaneously through a shared error-free link
during the delivery phase.
  First, centralized coded caching is studied assuming both the number and the
identity of the active users in the delivery phase are known by the server
during the placement phase. A novel group-based centralized coded caching (GBC)
scheme is proposed for a cache capacity of M = N/K. It is shown that this
scheme achieves a smaller delivery rate than all the known schemes in the
literature. The improvement is then extended to a wider range of cache
capacities through memory-sharing between the proposed scheme and other known
schemes in the literature. Next, the proposed centralized coded caching idea is
exploited in the decentralized setting, in which the identities of the users
that participate in the delivery phase are assumed to be unknown during the
placement phase. It is shown that the proposed decentralized caching scheme
also achieves a delivery rate smaller than the state-of-the-art. Numerical
simulations are also presented to corroborate our theoretical results.


title: Rolex: Resilience-Oriented Language Extensions for Extreme-Scale Systems

abstract:
  Future exascale high-performance computing (HPC) systems will be constructed
from VLSI devices that will be less reliable than those used today, and faults
will become the norm, not the exception. This will pose significant problems
for system designers and programmers, who for half-a-century have enjoyed an
execution model that assumed correct behavior by the underlying computing
system. The mean time to failure (MTTF) of the system scales inversely to the
number of components in the system and therefore faults and resultant system
level failures will increase, as systems scale in terms of the number of
processor cores and memory modules used. However every error detected need not
cause catastrophic failure. Many HPC applications are inherently fault
resilient. Yet it is the application programmers who have this knowledge but
lack mechanisms to convey it to the system.
  In this paper, we present new Resilience Oriented Language Extensions (Rolex)
which facilitate the incorporation of fault resilience as an intrinsic property
of the application code. We describe the syntax and semantics of the language
extensions as well as the implementation of the supporting compiler
infrastructure and runtime system. Our experiments show that an approach that
leverages the programmer's insight to reason about the context and significance
of faults to the application outcome significantly improves the probability
that an application runs to a successful conclusion.


title: Beyond knowing that: a new generation of epistemic logics

abstract:
  Epistemic logic has become a major field of philosophical logic ever since
the groundbreaking work by Hintikka (1962). Despite its various successful
applications in theoretical computer science, AI, and game theory, the
technical development of the field has been mainly focusing on the
propositional part, i.e., the propositional modal logics of "knowing that".
However, knowledge is expressed in everyday life by using various other
locutions such as "knowing whether", "knowing what", "knowing how" and so on
(knowing-wh hereafter). Such knowledge expressions are better captured in
quantified epistemic logic, as was already discussed by Hintikka (1962) and his
sequel works at length. This paper aims to draw the attention back again to
such a fascinating but largely neglected topic. We first survey what Hintikka
and others did in the literature of quantified epistemic logic, and then
advocate a new quantifier-free approach to study the epistemic logics of
knowing-wh, which we believe can balance expressivity and complexity, and
capture the essential reasoning patterns about knowing-wh. We survey our recent
line of work on the epistemic logics of "knowing whether", "knowing what" and
"knowing how" to demonstrate the use of this new approach.


title:
Optimized Coplanar Waveguide Resonators for a Superconductor-Atom
  Interface

abstract:
  We describe the design and characterization of superconducting coplanar
waveguide cavities tailored to facilitate strong coupling between
superconducting quantum circuits and single trapped Rydberg atoms. For initial
superconductor-atom experiments at 4.2 K, we show that resonator quality
factors above $10^4$ can be readily achieved. Furthermore, we demonstrate that
the incorporation of thick-film copper electrodes at a voltage antinode of the
resonator provides a route to enhance the zero-point electric fields of the
resonator in a trapping region that is 40 $\mu$m above the chip surface,
thereby minimizing chip heating from scattered trap light. The combination of
high resonator quality factor and strong electric dipole coupling between the
resonator and the atom should make it possible to achieve the strong coupling
limit of cavity quantum electrodynamics with this system.


title: Near-Optimal Finite-Length Scaling for Polar Codes over Large Alphabets

abstract:
  For any prime power $q$, Mori and Tanaka introduced a family of $q$-ary polar
codes based on $q$~by~$q$ Reed-Solomon polarization kernels. For transmission
over a $q$-ary erasure channel, they also derived a closed-form recursion for
the erasure probability of each effective channel. In this paper, we use that
expression to analyze the finite-length scaling of these codes on the $q$-ary
erasure channel with erasure probability $\epsilon\in(0,1)$. Our primary result
is that, for any $\gamma>0$ and $\delta>0$, there is a $q_{0}$ such that, for
all $q\geq q_{0}$, the fraction of effective channels with erasure rate at most
$N^{-\gamma}$ is at least $1-\epsilon-O(N^{-1/2+\delta})$, where $N=q^{n}$ is
the blocklength. Since this fraction cannot be larger than
$1-\epsilon-O(N^{-1/2})$, this establishes near-optimal finite-length scaling
for this family of codes. Our approach can be seen as an extension of a similar
analysis for binary polar codes by Hassani, Alishahi, and Urbanke.
  A similar analysis is also considered for $q$-ary polar codes with $m$ by $m$
polarizing matrices. This separates the effect of the alphabet size from the
effect of the matrix size. If the polarizing matrix at each stage is drawn
independently and uniformly from the set of invertible $m$ by $m$ matrices,
then the linear operator associated with the Lyapunov function analysis can be
written in closed form. To prove near-optimal scaling for polar codes with
fixed $q$ as $m$ increases, however, two technical obstacles remain. Thus, we
conclude by stating two concrete mathematical conjectures that, if proven,
would imply near-optimal scaling for fixed~$q$.


title: Unbiased Monte Carlo Simulation of Diffusion Processes

abstract:
  Monte Carlo simulations of diffusion processes often introduce bias in the
final result, due to time discretization. Using an auxiliary Poisson process,
it is possible to run simulations which are unbiased. In this article, we
propose such a Monte Carlo scheme which converges to the exact value. We manage
to keep the simulation variance finite in all cases, so that the strong law of
large numbers guarantees the convergence. Moreover, the simulation noise is a
decreasing function of the Poisson process intensity. Our method handles
multidimensional processes with nonconstant drifts and nonconstant
variance-covariance matrices. It also encompasses stochastic interest rates.


title: Visual Saliency Based on Scale-Space Analysis in the Frequency Domain

abstract:
  We address the issue of visual saliency from three perspectives. First, we
consider saliency detection as a frequency domain analysis problem. Second, we
achieve this by employing the concept of {\it non-saliency}. Third, we
simultaneously consider the detection of salient regions of different size. The
paper proposes a new bottom-up paradigm for detecting visual saliency,
characterized by a scale-space analysis of the amplitude spectrum of natural
images. We show that the convolution of the {\it image amplitude spectrum} with
a low-pass Gaussian kernel of an appropriate scale is equivalent to such an
image saliency detector. The saliency map is obtained by reconstructing the 2-D
signal using the original phase and the amplitude spectrum, filtered at a scale
selected by minimizing saliency map entropy. A Hypercomplex Fourier Transform
performs the analysis in the frequency domain. Using available databases, we
demonstrate experimentally that the proposed model can predict human fixation
data. We also introduce a new image database and use it to show that the
saliency detector can highlight both small and large salient regions, as well
as inhibit repeated distractors in cluttered images. In addition, we show that
it is able to predict salient regions on which people focus their attention.


title:
Poroelastic toughening in polymer gels: A theoretical and numerical
  study

abstract:
  We explore the Mode I fracture toughness of a polymer gel containing a
semi-infinite, growing crack. First, an expression is derived for the energy
release rate within the linearized, small-strain setting. This expression
reveals a crack tip velocity-independent toughening that stems from the
poroelastic nature of polymer gels. Then, we establish a poroelastic cohesive
zone model that allows us to describe the micromechanics of fracture in gels by
identifying the role of solvent pressure in promoting poroelastic toughening.
We evaluate the enhancement in the effective fracture toughness through
asymptotic analysis. We confirm our theoretical findings by means of numerical
simulations concerning the case of a steadily propagating crack. In broad
terms, our results explain the role of poroelasticity and of the processes
occurring in the fracturing region in promoting toughening of polymer gels.


title: Veldkamp Spaces: From (Dynkin) Diagrams to (Pauli) Groups

abstract:
  Regarding a Dynkin diagram as a specific point-line incidence structure
(where each line has just two points), one can associate with it a Veldkamp
space. Focusing on extended Dynkin diagrams of type $\widetilde{D}_n$, $4 \leq
n \leq 8$, it is shown that the corresponding Veldkamp space always contains a
distinguished copy of the projective space PG$(3,2)$. Proper labelling of the
vertices of the diagram (for $4 \leq n \leq 7$) by particular elements of the
two-qubit Pauli group establishes a bijection between the 15 elements of the
group and the 15 points of the PG$(3,2)$. The bijection is such that the
product of three elements lying on the same line is the identity and one also
readily singles out that particular copy of the symplectic polar space $W(3,2)$
of the PG$(3,2)$ whose lines correspond to triples of mutually commuting
elements of the group; in the latter case, in addition, we arrive at a unique
copy of the Mermin-Peres magic square. In the case of $n=8$, a more natural
labeling is that in terms of elements of the three-qubit Pauli group,
furnishing a bijection between the 63 elements of the group and the 63 points
of PG$(5,2)$, the latter being the maximum projective subspace of the
corresponding Veldkamp space; here, the points of the distinguished PG$(3,2)$
are in a bijection with the elements of a two-qubit subgroup of the three-qubit
Pauli group, yielding a three-qubit version of the Mermin-Peres square.
Moreover, save for $n=4$, each Veldkamp space is also endowed with some
`exceptional' point(s). Interestingly, two such points in the $n=8$ case define
a unique Fano plane whose inherited three-qubit labels feature solely the Pauli
matrix $Y$.


title: The Variable Coefficient Thin Obstacle Problem: Higher Regularity

abstract:
  In this article we continue our investigation of the thin obstacle problem
with variable coefficients which was initiated in \cite{KRS14}, \cite{KRSI}.
Using a partial Hodograph-Legendre transform and the implicit function theorem,
we prove higher order H\"older regularity for the regular free boundary, if the
associated coefficients are of the corresponding regularity. For the zero
obstacle this yields an improvement of a \emph{full derivative} for the free
boundary regularity compared to the regularity of the metric. In the presence
of non-zero obstacles or inhomogeneities, we gain \emph{three halves of a
derivative} for the free boundary regularity with respect to the regularity of
the inhomogeneity. Further we show analyticity of the regular free boundary for
analytic metrics. We also discuss the low regularity set-up of $W^{1,p}$
metrics with $p>n+1$ with and without ($L^p$) inhomogeneities. Key new
ingredients in our analysis are the introduction of generalized H\"older
spaces, which allow to interpret the transformed fully nonlinear, degenerate
(sub)elliptic equation as a perturbation of the Baouendi-Grushin operator,
various uses of intrinsic geometries associated with appropriate operators, the
application of the implicit function theorem to deduce (higher) regularity and
the splitting technique from \cite{KRSI}.


title: Framed cobordism and flow category moves

abstract:
  Framed flow categories were introduced by Cohen-Jones-Segal as a way of
encoding the flow data associated to a Floer functional. A framed flow category
gives rise to a CW-complex with one cell for each object of the category. The
idea is that the Floer invariant should take the form of the stable homotopy
type of the resulting complex, recovering the Floer cohomology as its singular
cohomology. Such a framed flow category was produced, for example, by
Lipshitz-Sarkar from the input of a knot diagram, resulting in a stable
homotopy type generalizing Khovanov cohomology.
  In this paper we give moves that change a framed flow category without
changing the associated stable homotopy type. These are inspired by moves that
can be performed in the Morse-Smale case without altering the underlying smooth
manifold. We posit that if two framed flow categories represent the same stable
homotopy type then a finite sequence of these moves is sufficient to connect
the two categories. This is directed towards the goal of reducing the study of
framed flow categories to a combinatorial calculus.
  We provide examples of calculations performed with these moves (related to
the Khovanov framed flow category), and prove some general results about the
simplification of framed flow categories via these moves.


title:
Collinear antiferromagnetism in trigonal SrMn$_{2}$As$_{2}$ revealed by
  single-crystal neutron diffraction

abstract:
  Fe pnictides and related materials have been a topic of intense research for
understanding the complex interplay between magnetism and superconductivity.
Here we report on the magnetic structure of SrMn$_{2}$As$_{2}$ that
crystallizes in a trigonal structure ($P\bar{3}m1$) and undergoes an
antiferromagnetic (AFM) transition at $T_{\textrm c}$ $= 118(2)$ K. The
magnetic susceptibility remains nearly constant at temperatures $T \le
T_{\textrm N}$ with $\textbf{H}\parallel \textbf{c}$ whereas it decreases
significantly with $\textbf{H}\parallel \textbf{ab}$. This shows that the
ordered Mn moments lie in the $\textbf{ab}$-plane instead of aligning along the
$\textbf{c}$-axis as in tetragonal BaMn$_{2}$As$_{2}$. Single-crystal neutron
diffraction measurements on SrMn$_{2}$As$_{2}$ demonstrate that the Mn moments
are ordered in a collinear N\'{e}el AFM phase with $180^\circ$ AFM alignment
between a moment and all nearest neighbor moments in the basal plane and also
perpendicular to it. Moreover, quasi-two-dimensional AFM order is manifested in
SrMn$_{2}$As$_{2}$ as evident from the temperature dependence of the order
parameter.


title: Frame-Dragging from Charged Rotating Body

abstract:
  In the present paper, we have considered the three parameters: mass, charge
and rotation to discuss their combined effect on frame dragging for a charged
rotating body. If we consider the ray of light which is emitted radially
outward from a rotating body then the frame dragging shows a periodic nature
with respect to coordinate $\phi$ (azimuthal angle). It has been found that the
value of frame dragging obtains a maximum at, $ \phi =\frac{\pi}{2}$ and a
minimum at $ \phi =\frac{3 \pi}{2}$.


title:
GMRT observation of neutral atomic hydrogen gas in the COSMOS field at
  $z \sim 0.37$

abstract:
  We present the results of HI spectral stacking analysis of Giant Metrewave
Radio Telescope (GMRT) observations targeting the COSMOS field. The GMRT data
cube contains 474 field galaxies with redshifts known from the zCOSMOS-bright
10k catalogue. Spectra for the galaxies are co-added and the stacked spectrum
allows us to make a $\sim 3\sigma$ measurement of the average HI mass. Using
this average HI mass along with the integral optical $B$-band luminosity of the
galaxies and the luminosity density of the COSMOS field, a volume normalisation
is applied to obtain the cosmic HI mass density ($\Omega_{\rm HI}$). We find a
cosmic HI mass density of $\Omega_{\rm HI}$ = (0.42 $\pm$ 0.16) $\times$
10$^{-3}$ at $z \sim 0.37$, which is the highest-redshift measurement of
$\Omega_{\rm HI}$ ever made using HI spectral stacking. The value we obtained
for $\Omega_{\rm HI}$ at $z \sim 0.37$ is consistent with that measured from
large blind 21-cm surveys at $z = 0$ as well as measurements from other HI
stacking experiments at lower redshifts. Our measurement in conjunction with
earlier measurements indicates that there has been no significant evolution of
HI gas abundance over the last 4 Gyr. A weighted mean of $\Omega_{\rm HI}$ from
all 21-cm measurements at redshifts $z \lesssim 0.4$ gives $\Omega_{\rm HI}$ =
(0.35 $\pm$ 0.01) $\times$ 10$^{-3}$. The $\Omega_{\rm HI}$ measured (from HI
21-cm emission measurements) at $z \lesssim 0.4$ is however approximately half
that measured from Damped Lyman-$\alpha$ Absorption (DLA) systems at $z \gtrsim
2$. Deeper surveys with existing and upcoming instruments will be critical to
understand the evolution of $\Omega_{\rm HI}$ in the redshift range
intermediate between $z \sim 0.4$ and the range probed by DLA observations.


title: Taut foliations

abstract:
  We describe notions of tautness that arise in the study of $C^0$ foliations,
$C^{1,0}$ or smoother foliations, and in geometry. We give examples to show
that these notions are different, and discuss how these differences impact some
classical foliation results.
  We construct examples of smoothly taut $C^{\infty,0}$ foliations that can be
$C^0$ approximated by both weakly symplectically fillable, universally tight
contact structures and by overtwisted contact structures.


title:
Spatial averaging of a dissipative particle dynamics model for active
  suspensions

abstract:
  Starting from a fine-scale dissipative particle dynamics (DPD) model of
self-motile point particles, we derive meso-scale continuum equations by
applying a spatial averaging version of the Irving--Kirkwood--Noll procedure.
Since the method does not rely on kinetic theory, the derivation is valid for
highly concentrated particle systems. Spatial averaging yields a stochastic
continuum equations similar to those of Toner and Tu. However, our theory also
involves a constitutive equation for the average fluctuation force. According
to this equation, both the strength and the probability distribution vary with
time and position through the effective mass density. The statistics of the
fluctuation force also depend on the fine scale dissipative force equation, the
physical temperature, and two additional parameters which characterize
fluctuation strengths. Although the self-propulsion force entering our DPD
model contains no explicit mechanism for aligning the velocities of neighboring
particles, our averaged coarse-scale equations include the commonly encountered
cubically nonlinear (internal) body force density.

categories: nlin.AO cond-mat.dis-nn cond-mat.mes-hall cond-mat.soft


title:
On the disorder-driven quantum transition in three-dimensional
  relativistic metals

abstract:
  The Weyl semimetals are topologically protected from a gap opening against
weak disorder in three dimensions. However, a strong disorder drives this
relativistic semimetal through a quantum transition towards a diffusive
metallic phase characterized by a finite density of states at the band
crossing. This transition is usually described by a perturbative
renormalization group in $d=2+\varepsilon$ of a $U(N)$ Gross-Neveu model in the
limit $N \to 0$. Unfortunately, this model is not multiplicatively
renormalizable in $2+\varepsilon$ dimensions: An infinite number of relevant
operators are required to describe the critical behavior. Hence its use in a
quantitative description of the transition beyond one-loop is at least
questionable. We propose an alternative route, building on the correspondence
between the Gross-Neveu and Gross-Neveu-Yukawa models developed in the context
of high energy physics. It results in a model of Weyl fermions with a random
non-Gaussian imaginary potential which allows one to study the critical
properties of the transition within a $d=4-\varepsilon$ expansion. We also
discuss the characterization of the transition by the multifractal spectrum of
wave functions.


title:
Hilbert schemes of lines and conics and automorphism groups of Fano
  threefolds

abstract:
  We discuss various results on Hilbert schemes of lines and conics and
automorphism groups of smooth Fano threefolds with Picard rank 1. Besides a
general review of facts well known to experts, the paper contains some new
results, for instance, we give a description of the Hilbert scheme of conics on
any smooth Fano threefold of index 1 and genus 10. We also show that the action
of the automorphism group of a Fano threefold $X$ of index 2 (respectively, 1)
on an irreducible component of its Hilbert scheme of lines (respectively,
conics) is faithful if the anticanonical class of $X$ is very ample with a
possible exception of several explicit cases. We use these faithfulness results
to prove finiteness of the automorphism groups of most Fano threefolds and
classify explicitly all Fano threefolds with infinite automorphism group. We
also discuss a derived category point of view on the Hilbert schemes of lines
and conics, and use this approach to identify some of them.


title: Role of the total isospin 3/2 component in three-nucleon reactions

abstract:
  We discuss the role of the three-nucleon isospin T=3/2 amplitude in elastic
neutron-deuteron scattering and in the deuteron breakup reaction. The
contribution of this amplitude originates from charge-independence breaking of
the nucleon-nucleon potential and is driven by the difference between
neutron-neutron (proton-proton) and neutron-proton forces. We study the
magnitude of that contribution to the elastic scattering and breakup
observables, taking the locally regularized chiral N4LO nucleon-nucleon
potential supplemented by the chiral N2LO three-nucleon force. For comparison
we employ also the Av18 nucleon-nucleon potential combined with the Urbana IX
three-nucleon force. We find that the isospin T=3/2 component is important for
the breakup reaction and the proper treatment of charge-independence breaking
in this case requires the inclusion of the 1S0 state with isospin T=3/2. For
neutron-deuteron elastic scattering the T=3/2 contributions are insignificant
and charge-independence breaking can be accounted for by using the effective
t-matrix generated with the so-called "2/3-1/3" rule.


title:
On the rigidity of geometric and spectral properties of Grassmannian
  frames

abstract:
  We study the rigidity properties of Grassmannian frames: basis-like sets of
unit vectors that correspond to optimal Grassmannian line packings. It is known
that Grassmannian frames characterized by the Welch bound must satisfy the
restrictive geometric and spectral conditions of being both equiangular and
tight; however, less is known about the necessary properties of other types of
Grassmannian frames. We examine explicit low-dimensional examples of
orthoplectic Grassmannian frames and conclude that, in general, the necessary
conditions for the existence of Grassmannian frames can be much less
restrictive. In particular, we exhibit a pair of $5$-element Grassmannian
frames in $\mathbb C^2$ manifesting with differently sized angle sets and
different reconstructive properties (ie, only one of them is a tight frame).
This illustrates the complexity of the line packing problem, as there are cases
where a solution may coexist with another solution of a different geometric and
spectral character. Nevertheless, we find that these "twin" instances still
respect a certain rigidity, as there is a necessary trade-off between their
tightness properties and the cardinalities of their angle sets. The proof of
this depends on the observation that the traceless embedding of Conway, Hardin
and Sloane sends the vectors of a unit-norm, tight frame to a zero-summing set
on a higher dimensional sphere. In addition, we review some of the known bounds
for characterizing optimal line packings in $\mathbb C^2$ and discuss several
examples of Grassmannian frames achieving them.


title: Flavor Mixing Phenomenology in Supersymmetric Models

abstract:
  This dissertation investigates the flavor mixing effects in supersymmetric
models on electroweak precision observables, Higgs boson mass predictions,
B-physics observables, quark flavor violating Higgs decays, lepton flavor
violating charged lepton decays and lepton flavor violating Higgs decays. The
flavor mixing effects are studied in model independent way i.e. by putting
off-diagonal entries in the sfermion mass matrix by hand as well as in the
minimal flavor violating constrained MSSM, where mixing can originate from CKM
matrix in the case of squarks and from PMNS matrix in the case of sleptons. We
found that flavor mixing can have large impact to some observables, enabling us
to put new constraints on parameter space in supersymmetric models.


title:
Existence of invariant measures for the stochastic damped Schr\"odinger
  equation

abstract:
  In this paper, we address the long time behaviour of solutions of the
stochastic Schrodinger equation in $\mathbb{R}^d$. We prove the existence of an
invariant measure and establish asymptotic compactness of solutions, implying
in particular the existence of an ergodic measure.


title: Origin of the Metal-Insulator Transition of Indium Atom Wires on Si(111)

abstract:
  As a prototypical one-dimensional electron system, self-assembled indium (In)
nanowires on the Si(111) surface have been believed to drive a metal-insulator
transition by a charge-density-wave (CDW) formation due to electron-phonon
coupling. Here, our first-principles calculations demonstrate that the
structural phase transition from the high-temperature 4x1 phase to the
low-temperature 8x2 phase occurs through an exothermic reaction with the
consecutive bond-breaking and bond-making processes, giving rise to an energy
barrier between the two phases as well as a gap opening. This atomistic picture
for the phase transition not only identifies its first-order nature but also
solves a long-standing puzzle of the origin of the metal-insulator transition
in terms of the x2 periodic lattice reconstruction of In hexagons via bond
breakage and new bond formation, not by the Peierls instability-driven CDW
formation.


title:
Sensitivity Projections for Dark Matter Searches with the Fermi Large
  Area Telescope

abstract:
  The nature of dark matter is a longstanding enigma of physics; it may consist
of particles beyond the Standard Model that are still elusive to experiments.
Among indirect search techniques, which look for stable products from the
annihilation or decay of dark matter particles, or from axions coupling to
high-energy photons, observations of the $\gamma$-ray sky have come to
prominence over the last few years, because of the excellent sensitivity of the
Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope mission. The
LAT energy range from 20 MeV to above 300 GeV is particularly well suited for
searching for products of the interactions of dark matter particles. In this
report we describe methods used to search for evidence of dark matter with the
LAT, and review the status of searches performed with up to six years of LAT
data. We also discuss the factors that determine the sensitivities of these
searches, including the magnitudes of the signals and the relevant backgrounds,
considering both statistical and systematic uncertainties. We project the
expected sensitivities of each search method for 10 and 15 years of LAT data
taking. In particular, we find that the sensitivity of searches targeting dwarf
galaxies, which provide the best limits currently, will improve faster than the
square root of observing time. Current LAT limits for dwarf galaxies using six
years of data reach the thermal relic level for masses up to 120 GeV for the
$b\bar{b}$ annihilation channel for reasonable dark matter density profiles.
With projected discoveries of additional dwarfs, these limits could extend to
about 250 GeV. With as much as 15 years of LAT data these searches would be
sensitive to dark matter annihilations at the thermal relic cross section for
masses to greater than 400 GeV (200 GeV) in the $b\bar{b}$ ($\tau^+ \tau^-$)
annihilation channels.


title: A simple proof of the non-rationality of a general quartic double solid

abstract:
  The aim of this short note is to give a simple proof of the non-rationality
of the double cover of the three-dimensional projective space branched over a
sufficiently general quartic.


title:
A spatio-temporal stochastic pattern generator for simulation of
  uncertainties in geophysical ensemble prediction and ensemble data
  assimilation

abstract:
  A generator of spatio-temporal pseudo-random Gaussian fields that satisfy the
"proportionality of scales" property (Tsyroulnikov, 2001) is presented. The
generator is based on a third-order in time stochastic differential equation
with a pseudo-differential spatial operator defined on a limited area 2D or 3D
domain in the Cartesian coordinate system. The generated pseudo-random fields
are homogeneous and isotropic in spacetime (with the scaled vertical and
temporal coordinates). The correlation functions in any spatio-temporal
direction belong to the Mat\'ern class. The spatio-temporal correlations are
non-separable. A spectral-space numerical solver is implemented and accelerated
exploiting properties of real-world geophysical fields, in particular,
smoothness of their spatial spectra. The generator is designed to create
additive or multiplicative, or other spatio-temporal perturbations that
represent uncertainties in numerical prediction models in geophysics. The
program code of the generator is publicly available.


title: Mixing Dirichlet Topic Models and Word Embeddings to Make lda2vec

abstract:
  Distributed dense word vectors have been shown to be effective at capturing
token-level semantic and syntactic regularities in language, while topic models
can form interpretable representations over documents. In this work, we
describe lda2vec, a model that learns dense word vectors jointly with
Dirichlet-distributed latent document-level mixtures of topic vectors. In
contrast to continuous dense document representations, this formulation
produces sparse, interpretable document mixtures through a non-negative simplex
constraint. Our method is simple to incorporate into existing automatic
differentiation frameworks and allows for unsupervised document representations
geared for use by scientists while simultaneously learning word vectors and the
linear relationships between them.


title: A Dirichlet Process Characterization of RBM in a Wedge

abstract:
  Reflected Brownian motion (RBM) in a wedge is a 2-dimensional stochastic
process Z whose state space in R^2 is given in polar coordinates by
S={(r,theta): r >= 0, 0 <= theta <= xi} for some 0 < xi < 2 pi. Let alpha=
(theta_1+theta_2)/xi, where -pi/2 < theta_1,theta_2 < pi/2 are the directions
of reflection of Z off each of the two edges of the wedge as measured from the
corresponding inward facing normal. We prove that in the case of 1 < alpha < 2,
RBM in a wedge is a Dirichlet process. Specifically, its unique Doob-Meyer type
decomposition is given by Z=X+Y, where X is a two-dimensional Brownian motion
and Y is a continuous process of zero energy. Furthermore, we show that for p >
alpha , the strong p-variation of the sample paths of Y is finite on compact
intervals, and, for 0 < p <= alpha, the strong p-variation of Y is infinite on
[0,T] whenever Z has been started from the origin. We also show that on
excursion intervals of Z away from the origin, (Z,Y) satisfies the standard
Skorokhod problem for X. However, on the entire time horizon (Z,Y) does not
satisfy the standard Skorokhod problem for X, but nevertheless we show that it
satisfies the extended Skorkohod problem.


title: Window functions and sigmoidal behaviour of memristive systems

abstract:
  A common approach to model memristive systems is to include empirical window
functions to describe edge effects and non-linearities in the change of the
memristance. We demonstrate that under quite general conditions, each window
function can be associated with a sigmoidal curve relating the normalised
time-dependent memristance to the time integral of the input. Conversely, this
explicit relation allows us to derive window functions suitable for the
mesoscopic modelling of memristive systems from a variety of well-known
sigmoidals. Such sigmoidal curves are defined in terms of measured variables
and can thus be extracted from input and output signals of a device and then
transformed to its corresponding window. We also introduce a new generalised
window function that allows the flexible modelling of asymmetric edge effects
in a simple manner.


title: Deterministic MST Sparsification in the Congested Clique

abstract:
  We give a simple deterministic constant-round algorithm in the congested
clique model for reducing the number of edges in a graph to $n^{1+\varepsilon}$
while preserving the minimum spanning forest, where $\varepsilon > 0$ is any
constant. This implies that in the congested clique model, it is sufficient to
improve MST and other connectivity algorithms on graphs with slightly
superlinear number of edges to obtain a general improvement. As a byproduct, we
also obtain a simple alternative proof showing that MST can be computed
deterministically in $O(\log \log n)$ rounds.


title:
Electrostatic control of quantum Hall ferromagnetic transition, a step
  toward reconfigurable network of helical channels

abstract:
  Ferromagnetic transitions between quantum Hall states with different
polarization at a fixed filling factor can be studied by varying the ratio of
cyclotron and Zeeman energies in tilted magnetic field experiments. However, an
ability to locally control such transitions at a fixed magnetic field would
open a range of attractive applications, e.g. formation of a reconfigurable
network of one-dimensional helical domain walls in a two-dimensional plane.
Coupled to a superconductor, such domain walls can support non-Abelian
excitation. In this article we report development of heterostructures where
quantum Hall ferromagnetic (QHFm) transition can be controlled locally by
electrostatic gating. A high mobility two-dimensional electron gas is formed in
CdTe quantum wells with engineered placement of paramagnetic Mn impurities.
Gate-induced electrostatic field shifts electron wavefunction in the growth
direction and changes overlap between electrons in the quantum well and d-shell
electrons on Mn, thus controlling the s-d exchange interaction and the field of
the QHFm transition. The demonstrated shift of the QHFm transition at a filling
factor $\nu=2$ is large enough to allow full control of spin polarization at a
fixed magnetic field.


title:
DEMNUni: ISW, Rees-Sciama, and weak-lensing in the presence of massive
  neutrinos

abstract:
  We present, for the first time in the literature, a full reconstruction of
the total (linear and non-linear) ISW/Rees-Sciama effect in the presence of
massive neutrinos, together with its cross-correlations with CMB-lensing and
weak-lensing signals. The present analyses make use of all-sky maps extracted
via ray-tracing across the gravitational potential distribution provided by the
"Dark Energy and Massive Neutrino Universe" (DEMNUni) project, a set of
large-volume, high-resolution cosmological N-body simulations, where neutrinos
are treated as separate collisionless particles. We correctly recover, at
$1-2\%$ accuracy, the linear predictions from CAMB. Concerning the CMB-lensing
and weak-lensing signals, we also recover, with similar accuracy, the signal
predicted by Boltzmann codes, once non-linear neutrino corrections to Halofit
are accounted for. Interestingly, in the ISW/Rees-Sciama signal, and its cross
correlation with lensing, we find an excess of power with respect to the
massless case, due to free streaming neutrinos, roughly at the transition scale
between the linear and non-linear regimes. The excess is $\sim 5-10\%$ at
$l\sim 100$ for the ISW/Rees-Sciama auto power spectrum, depending on the total
neutrino mass $M_\nu$, and becomes a factor of $\sim 4$ for $M_\nu=0.3$ eV, at
$l\sim 600$, for the ISW/Rees-Sciama cross power with CMB-lensing. This effect
should be taken into account for the correct estimation of the CMB temperature
bispectrum in the presence of massive neutrinos.


title: Electron and phonon properties and gas storage in carbon honeycomb

abstract:
  A new kind of three-dimensional carbon allotropes, termed carbon honeycomb
(CHC), has recently been synthesized [PRL 116, 055501 (2016)]. Based on the
experimental results, a family of graphene networks are constructed, and their
electronic and phonon properties are calculated by using first principles
methods. All networks are porous metal with two types of electron transport
channels along the honeycomb axis and they are isolated from each other: one
type of channels is originated from the orbital interactions of the carbon
zigzag chains and is topologically protected, while the other type of channels
is from the straight lines of the carbon atoms that link the zigzag chains and
is topologically trivial. The velocity of the electrons can reach ~10^6 m/s.
Phonon transport in these allotropes is strongly anisotropic, and the thermal
conductivities can be very low when compared with graphite by at least a factor
of 15. Our calculations further indicate that these porous carbon networks
possess high storage capacity for gaseous atoms and molecules in agreement with
experiment.


title: Training Neural Networks Without Gradients: A Scalable ADMM Approach

abstract:
  With the growing importance of large network models and enormous training
datasets, GPUs have become increasingly necessary to train neural networks.
This is largely because conventional optimization algorithms rely on stochastic
gradient methods that don't scale well to large numbers of cores in a cluster
setting. Furthermore, the convergence of all gradient methods, including batch
methods, suffers from common problems like saturation effects, poor
conditioning, and saddle points. This paper explores an unconventional training
method that uses alternating direction methods and Bregman iteration to train
networks without gradient descent steps. The proposed method reduces the
network training problem to a sequence of minimization sub-steps that can each
be solved globally in closed form. The proposed method is advantageous because
it avoids many of the caveats that make gradient methods slow on highly
non-convex problems. The method exhibits strong scaling in the distributed
setting, yielding linear speedups even when split over thousands of cores.


title:
Stochastic population growth in spatially heterogeneous environments:
  The density-dependent case

abstract:
  This work is devoted to studying the dynamics of a structured population that
is subject to the combined effects of environmental stochasticity, competition
for resources, spatio-temporal heterogeneity and dispersal. The population is
spread throughout $n$ patches whose population abundances are modelled as the
solutions of a system of nonlinear stochastic differential equations living on
$[0,\infty)^n$.
  We prove that $r$, the stochastic growth rate of the total population in the
absence of competition, determines the long-term behaviour of the population.
The parameter $r$ can be expressed as the Lyapunov exponent of an associated
linearized system of stochastic differential equations. Detailed analysis shows
that if $r>0$, the population abundances converge polynomially fast to a unique
invariant probability measure on $(0,\infty)^n$, while when $r<0$, the
population abundances of the patches converge almost surely to $0$
exponentially fast. This generalizes and extends the results of Evans et al
(2014 J. Math. Biol.) and proves one of their conjectures.
  Compared to recent developments, our model incorporates very general
density-dependent growth rates and competition terms. Furthermore, we prove
that persistence is robust to small, possibly density dependent, perturbations
of the growth rates, dispersal matrix and covariance matrix of the
environmental noise. Our work allows the environmental noise driving our system
to be degenerate. This is relevant from a biological point of view since, for
example, the environments of the different patches can be perfectly correlated.
As an example we fully analyze the two-patch case, $n=2$, and show that the
stochastic growth rate is a decreasing function of the dispersion rate. In
particular, coupling two sink patches can never yield persistence, in contrast
to the results from the non-degenerate setting treated by Evans et al.


title:
A theoretical approach to understand spatial organization in complex
  ecologies

abstract:
  Predicting the fate of ecologies is a daunting, albeit extremely important,
task. As part of this task one needs to develop an understanding of the
organization, hierarchies, and correlations among the species forming the
ecology. Focusing on complex food networks we present a theoretical method that
allows to achieve this understanding. Starting from the adjacency matrix the
method derives specific matrices that encode the various inter-species
relationships. The full potential of the method is achieved in a spatial
setting where one obtains detailed predictions for the emerging space-time
patterns. For a variety of cases these theoretical predictions are verified
through numerical simulations.


title:
Shaping the Future through Innovations: From Medical Imaging to
  Precision Medicine

abstract:
  Medical images constitute a source of information essential for disease
diagnosis, treatment and follow-up. In addition, due to its patient-specific
nature, imaging information represents a critical component required for
advancing precision medicine into clinical practice. This manuscript describes
recently developed technologies for better handling of image information:
photorealistic visualization of medical images with Cinematic Rendering,
artificial agents for in-depth image understanding, support for minimally
invasive procedures, and patient-specific computational models with enhanced
predictive power. Throughout the manuscript we will analyze the capabilities of
such technologies and extrapolate on their potential impact to advance the
quality of medical care, while reducing its cost.


title: Unitarity and microscopic acausality in a nonlocal theory

abstract:
  We consider unitarity and causality in a higher-derivative theory of infinite
order, where propagators fall off more quickly in the ultraviolet due to the
presence of a transcendental entire function of the momentum. Like Lee-Wick
theories, these field theories might provide new avenues for addressing the
hierarchy problem; unlike Lee-Wick theories, tree-level propagators do not have
additional poles corresponding to unobserved particles with unusual properties.
We consider microscopic acausality in these nonlocal theories. The acausal
ordering of production and decay vertices for ordinary resonant particles may
provide a phenomenologically distinct signature for these models.


title: Extended Kalman Filter on SE(3) for Geometric Control of a Quadrotor UAV

abstract:
  An extended Kalman filter (EKF) is developed on the special Euclidean group,
SE(3) for geometric control of a quadrotor UAV. It is obtained by performing an
extensive linearization on SE(3) to estimate the state of the quadrotor from
noisy measurements. Proposed estimator considers all the coupling effects
between rotational and translational dynamics, and it is developed in a
coordinate-free fashion. The desirable features of the proposed EKF are
illustrated by numerical examples and experimental results for several
scenarios. The proposed estimation scheme on SE(3) has been unprecedented and
these results can be particularly useful for aggressive maneuvers in GPS denied
environments or in situations where parts of onboard sensors fail.


title:
Testing lowered isothermal models with direct N-body simulations of
  globular clusters

abstract:
  Several self-consistent models have been proposed, aiming at describing the
phase space distribution of stars in globular clusters. This study explores the
ability of the recently proposed LIMEPY models (Gieles & Zocchi) to reproduce
the dynamical properties of direct N-body models of a cluster in a tidal field,
during its entire evolution. These dynamical models include prescriptions for
the truncation and the degree of radially-biased anisotropy contained in the
system, allowing us to explore the interplay between the role of anisotropy and
tides in various stages of the life of star clusters. We show that the amount
of anisotropy in an initially tidally underfilling cluster increases in the
pre-collapse phase, and then decreases with time, due to the effect of the
external tidal field on its spatial truncation. This is reflected in the
correspondent model parameters, and the best-fit models reproduce the main
properties of the cluster at all stages of its evolution, except for the phases
immediately preceding and following core collapse. We also notice that the
best-fit LIMEPY models are significantly different from isotropic King models,
especially in the first part of the evolution of the cluster. Our results put
limits on the amount of radial anisotropy that can be expected for clusters
evolving in a tidal field, which is important to understand other factors that
could give rise to similar observational signatures, such as the presence of an
intermediate-mass black hole.


title: A Study on Features and Limitations of On-line C Compilers

abstract:
  Compilers are used to run programs that are written in a range of designs
from text to executable formats. With the advent of the internet, studies
related to the development of cloud based compilers are being carried out.
There is a considerable increase of on-line compilers enabling on-line
compilation of user programs without any mandate to. This study is specific to
on-line C compilers to investigate the correctness, issues and limitations.


title:
Searching for the 3.5 keV Line in the Stacked Suzaku Observations of
  Galaxy Clusters

abstract:
  We perform a detailed study of the stacked Suzaku observations of 47 galaxy
clusters, spanning a redshift range of 0.01-0.45, to search for the
unidentified 3.5 keV line. This sample provides an independent test for the
previously detected line. We detect only a 2sigma-significant spectral feature
at 3.5 keV in the spectrum of the full sample. When the sample is divided into
two subsamples (cool-core and non-cool core clusters), cool-core subsample
shows no statistically significant positive residuals at the line energy. A
very weak (2sigma-confidence) spectral feature at 3.5 keV is permitted by the
data from the non-cool core clusters sample. The upper limit on a neutrino
decay mixing angle from the full Suzaku sample is consistent with the previous
detections in the stacked XMM-Newton sample of galaxy clusters (which had a
higher statistical sensitivity to faint lines), M31, and Galactic Center at a
90% confidence level. However, the constraint from the present sample, which
does not include the Perseus cluster, is in tension with previously reported
line flux observed in the core of the Perseus cluster with XMM-Newton and
Suzaku.


title:
Pseudorapidity dependence of the anisotropic flow of charged particles
  in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=2.76$ TeV

abstract:
  We present measurements of the elliptic ($\mathrm{v}_2$), triangular
($\mathrm{v}_3$) and quadrangular ($\mathrm{v}_4$) anisotropic azimuthal flow
over a wide range of pseudorapidities ($-3.5< \eta < 5$). The measurements are
performed with Pb-Pb collisions at $\sqrt{s_{\text{NN}}} = 2.76$ TeV using the
ALICE detector at the Large Hadron Collider (LHC). The flow harmonics are
obtained using two- and four-particle correlations from nine different
centrality intervals covering central to peripheral collisions. We find that
the shape of $\mathrm{v}_n(\eta)$ is largely independent of centrality for the
flow harmonics $n=2-4$, however the higher harmonics fall off more steeply with
increasing $|\eta|$. We assess the validity of extended longitudinal scaling of
$\mathrm{v}_2$ by comparing to lower energy measurements, and find that the
higher harmonic flow coefficients are proportional to the charged particle
densities at larger pseudorapidities. Finally, we compare our measurements to
both hydrodynamical and transport models, and find they both have challenges
when it comes to describing our data.


title:
Testing the lognormality of the galaxy and weak lensing convergence
  distributions from Dark Energy Survey maps

abstract:
  It is well known that the probability distribution function (PDF) of galaxy
density contrast is approximately lognormal; whether the PDF of mass
fluctuations derived from weak lensing convergence (kappa_WL) is lognormal is
less well established. We derive PDFs of the galaxy and projected matter
density distributions via the Counts in Cells (CiC) method. We use maps of
galaxies and weak lensing convergence produced from the Dark Energy Survey
(DES) Science Verification data over 139 deg^2. We test whether the underlying
density contrast is well described by a lognormal distribution for the
galaxies, the convergence and their joint PDF. We confirm that the galaxy
density contrast distribution is well modeled by a lognormal PDF convolved with
Poisson noise at angular scales from 10-40 arcmin (corresponding to physical
scales of 3-10 Mpc). We note that as kappa_WL is a weighted sum of the mass
fluctuations along the line of sight, its PDF is expected to be only
approximately lognormal. We find that the kappa_WL distribution is well modeled
by a lognormal PDF convolved with Gaussian shape noise at scales between 10 and
20 arcmin, with a best-fit chi^2/DOF of 1.11 compared to 1.84 for a Gaussian
model, corresponding to p-values 0.35 and 0.07 respectively, at a scale of 10
arcmin. Above 20 arcmin a simple Gaussian model is sufficient. The joint PDF is
also reasonably fitted by a bivariate lognormal. As a consistency check we
compare the variances derived from the lognormal modelling with those directly
measured via CiC. Our methods are validated against maps from the MICE Grand
Challenge N-body simulation.


title: Blink Rate Variability during resting and reading sessions

abstract:
  It has been shown that blinks occur not only to moisturize eyes and as a
defensive response to the environment, but are also caused by mental processes.
In this paper, we investigate statistical characteristics of blinks and blink
rate variability of 11 subjects. The subjects are presented with a
reading/memorization session preceded and followed by a resting session. EEG
signals were recorded during these sessions. The signals from the two front
electrodes were then analyzed, and times of the blinks were detected. We
discovered that compared to the resting sessions, reading session is
characterized by a lower number of blinks. However, there was no significant
difference in standard deviation in the blink rate variability. We also noticed
that in terms of complexity measures, the blink rate variability is located
somewhere in between white and pink noises, being closer to the white noise
during reading. We also found that the average of inter-blink intervals
increases during reading/memorization, thus longer inter-blink intervals could
be associated with a mental workload.


title:
Markov Chain methods for the bipartite Boolean quadratic programming
  problem

abstract:
  We study the Bipartite Boolean Quadratic Programming Problem (BBQP) which is
an extension of the well known Boolean Quadratic Programming Problem (BQP).
Applications of the BBQP include mining discrete patterns from binary data,
approximating matrices by rank-one binary matrices, computing the cut-norm of a
matrix, and solving optimisation problems such as maximum weight biclique,
bipartite maximum weight cut, maximum weight induced sub-graph of a bipartite
graph, etc. For the BBQP, we first present several algorithmic components,
specifically, hill climbers and mutations, and then show how to combine them in
a high-performance metaheuristic. Instead of hand-tuning a standard
metaheuristic to test the efficiency of the hybrid of the components, we chose
to use an automated generation of a multi-component metaheuristic to save human
time, and also improve objectivity in the analysis and comparisons of
components. For this we designed a new metaheuristic schema which we call
Conditional Markov Chain Search (CMCS). We show that CMCS is flexible enough to
model several standard metaheuristics; this flexibility is controlled by
multiple numeric parameters, and so is convenient for automated generation. We
study the configurations revealed by our approach and show that the best of
them outperforms the previous state-of-the-art BBQP algorithm by several orders
of magnitude. In our experiments we use benchmark instances introduced in the
preliminary version of this paper and described here, which have already become
the de facto standard in the BBQP literature.


title:
Reconstruction of spectral solar irradiance since 1700 from simulated
  magnetograms

abstract:
  We present a reconstruction of the spectral solar irradiance since 1700 using
the SATIRE-T2 (Spectral And Total Irradiance REconstructions for the Telescope
era version 2) model. This model uses as input magnetograms simulated with a
surface flux transport model fed with semi-synthetic records of emerging
sunspot groups. We used statistical relationships between the properties of
sunspot group emergence, such as the latitude, area, and tilt angle, and the
sunspot cycle strength and phase to produce semi-synthetic sunspot group
records starting in the year 1700. The semisynthetic records are fed into a
surface flux transport model to obtain daily simulated magnetograms that map
the distribution of the magnetic flux in active regions (sunspots and faculae)
and their decay products on the solar surface. The magnetic flux emerging in
ephemeral regions is accounted for separately based on the concept of extended
cycles whose length and amplitude are linked to those of the sunspot cycles
through the sunspot number. The magnetic flux in each surface component
(sunspots, faculae and network, and ephemeral regions) was used to compute the
spectral and total solar irradiance between the years 1700 and 2009. This
reconstruction is aimed at timescales of months or longer although the model
returns daily values. We found that SATIRE-T2, besides reproducing other
relevant observations such as the total magnetic flux, reconstructs the total
solar irradiance (TSI) on timescales of months or longer in good agreement with
the PMOD composite of observations, as well as with the reconstruction starting
in 1878 based on the RGO-SOON data. The model predicts an increase in the TSI
of 1.2[+0.2, -0.3] Wm-2 between 1700 and the present. The spectral irradiance
reconstruction is in good agreement with the UARS/SUSIM measurements as well as
the Lyman-alpha composite.


title: Software Assumptions Failure Tolerance: Role, Strategies, and Visions

abstract:
  At our behest or otherwise, while our software is being executed, a huge
variety of design assumptions is continuously matched with the truth of the
current condition. While standards and tools exist to express and verify some
of these assumptions, in practice most of them end up being either sifted off
or hidden between the lines of our codes. Across the system layers, a complex
and at times obscure web of assumptions determines the quality of the match of
our software with its deployment platforms and run-time environments. Our
position is that it becomes increasingly important being able to design
software systems with architectural and structuring techniques that allow
software to be decomposed to reduce its complexity, but without hiding in the
process vital hypotheses and assumptions. In this paper we discuss this
problem, introduce three potentially dangerous consequences of its denial, and
propose three strategies to facilitate their treatment. Finally we propose our
vision towards a new holistic approach to software development to overcome the
shortcomings offered by fragmented views to the problem of assumption failures.


title:
Mapping knowledge translation and innovation processes in Cancer Drug
  Development: the case of liposomal doxorubicin

abstract:
  We explored how the knowledge translation and innovation processes are
structured when they result in innovations, as in the case of liposomal
doxorubicin research. In order to map the processes, a literature network
analysis was made through Cytoscape and semantic analysis was performed by
GOPubmed which is based in the controlled vocabularies MeSH (Medical Subject
Headings) and GO (Gene Ontology). We found clusters related to different stages
of the technological development (invention, innovation and imitation) and the
knowledge translation process (preclinical, translational and clinical
research), and we were able to map the historic emergence of Doxil as a
paradigmatic nanodrug. This research could be a powerful methodological tool
for decision-making and innovation management in drug delivery research.


title: A Jordan-like decomposition theorem for valuations on star bodies

abstract:
  We show that every radial continuous valuation $V:\mathcal S_0^n\rightarrow
\mathbb R$ defined on the $n$-dimensional star bodies $\mathcal S_0^n$, and
verifying $V(\{0\})=0$, can be decomposed as a sum $V=V^+-V^-$, where both
$V^+$ and $V^-$ are positive radial continuous valuations on $\mathcal S_0^n$
with $V^+(\{0\})=V^-(\{0\})=0$.
  As an application, we show that radial continuous rotationally invariant
valuations $V$ on $\mathcal S_0^n$ can be characterized as the applications on
star bodies which can be written as $$V(K)=\int_{S^{n-1}}\theta(\rho_K)dm,$$
where $\theta:[0,\infty)\rightarrow \mathbb R$ is a continuous function,
$\rho_K$ is the radial function associated to $K$ and $m$ is the Lebesgue
measure on $S^{n-1}$.
  This completes recent work of the second named author, where an analogous
result is proved for the case of {\em positive} radial continuous rotationally
invariant valuations.


title: A Graph-based Model for GPU Caching Problems

abstract:
  Modeling data sharing in GPU programs is a challenging task because of the
massive parallelism and complex data sharing patterns provided by GPU
architectures. Better GPU caching efficiency can be achieved through careful
task scheduling among different threads. Traditionally, in the field of
parallel computing, graph partition models are used to model data communication
and guide task scheduling. However, we discover that the previous methods are
either inaccurate or expensive when applied to GPU programs. In this paper, we
propose a novel task partition model that is accurate and gives rise to the
development of fast and high quality task/data reorganization algorithms. We
demonstrate the effectiveness of the proposed model by rigorous theoretical
analysis of the algorithm bounds and extensive experimental analysis. The
experimental results show that it achieves significant performance improvement
across a representative set of GPU applications.


title:
Perfect control of reflection and refraction using spatially dispersive
  metasurfaces

abstract:
  Non-uniform metasurfaces (electrically thin composite layers) can be used for
shaping refracted and reflected electromagnetic waves. However, known design
approaches based on the generalized refraction and reflection laws do not allow
realization of perfectly performing devices: there are always some parasitic
reflections into undesired directions. In this paper we introduce and discuss a
general approach to the synthesis of metasurfaces for full control of
transmitted and reflected plane waves and show that perfect performance can be
realized. The method is based on the use of an equivalent impedance matrix
model which connects the tangential field components at the two sides on the
metasurface. With this approach we are able to understand what physical
properties of the metasurface are needed in order to perfectly realize the
desired response. Furthermore, we determine the required polarizabilities of
the metasurface unit cells and discuss suitable cell structures. It appears
that only spatially dispersive metasurfaces allow realization of perfect
refraction and reflection of incident plane waves into arbitrary directions. In
particular, ideal refraction is possible only if the metasurface is
bianisotropic (weak spatial dispersion), and ideal reflection without
polarization transformation requires spatial dispersion with a specific,
strongly non-local response to the fields.


title: Fast Compatibility Testing for Phylogenies with Nested Taxa

abstract:
  Semi-labeled trees are phylogenies whose internal nodes may be labeled by
higher-order taxa. Thus, a leaf labeled Mus musculus could nest within a
subtree whose root node is labeled Rodentia, which itself could nest within a
subtree whose root is labeled Mammalia. Suppose we are given collection
$\mathcal P$ of semi-labeled trees over various subsets of a set of taxa. The
ancestral compatibility problem asks whether there is a semi-labeled tree
$\mathcal T$ that respects the clusterings and the ancestor/descendant
relationships implied by the trees in $\mathcal P$. We give a
$\tilde{O}(M_{\mathcal{P}})$ algorithm for the ancestral compatibility problem,
where $M_{\mathcal{P}}$ is the total number of nodes and edges in the trees in
$\mathcal P$. Unlike the best previous algorithm, the running time of our
method does not depend on the degrees of the nodes in the input trees.


title: Low-Complexity Stochastic Generalized Belief Propagation

abstract:
  The generalized belief propagation (GBP), introduced by Yedidia et al., is an
extension of the belief propagation (BP) algorithm, which is widely used in
different problems involved in calculating exact or approximate marginals of
probability distributions. In many problems, it has been observed that the
accuracy of GBP considerably outperforms that of BP. However, because in
general the computational complexity of GBP is higher than BP, its application
is limited in practice.
  In this paper, we introduce a stochastic version of GBP called stochastic
generalized belief propagation (SGBP) that can be considered as an extension to
the stochastic BP (SBP) algorithm introduced by Noorshams et al. They have
shown that SBP reduces the complexity per iteration of BP by an order of
magnitude in alphabet size. In contrast to SBP, SGBP can reduce the computation
complexity if certain topological conditions are met by the region graph
associated to a graphical model. However, this reduction can be larger than
only one order of magnitude in alphabet size. In this paper, we characterize
these conditions and the amount of computation gain that we can obtain by using
SGBP. Finally, using similar proof techniques employed by Noorshams et al., for
general graphical models satisfy contraction conditions, we prove the
asymptotic convergence of SGBP to the unique GBP fixed point, as well as
providing non-asymptotic upper bounds on the mean square error and on the high
probability error.


title: Reactor Neutrino Spectra

abstract:
  We present a review of the antineutrino spectra emitted from reactors.
Knowledge of these and their associated uncertainties are crucial for neutrino
oscillation studies. The spectra used to-date have been determined by either
conversion of measured electron spectra to antineutrino spectra or by summing
over all of the thousands of transitions that makeup the spectra using modern
databases as input. The uncertainties in the subdominant corrections to
beta-decay plague both methods, and we provide estimates of these
uncertainties. Improving on current knowledge of the antineutrino spectra from
reactors will require new experiments. Such experiments would also address the
so-called reactor neutrino anomaly and the possible origin of the shoulder
observed in the antineutrino spectra measured in recent high-statistics reactor
neutrino experiments.


title: Differential equations defined on algebraic curves

abstract:
  The class of ordinary linear constant coefficient differential equations is
naturally embedded into a wider class by associating differential equations to
algebraic curves.


title:
Multidimensional Thermoelasticity for Nonsimple Materials --
  Well-Posedness and Long-Time Behavior

abstract:
  An initial-boundary value problem for the multidimensional type III
thermoelaticity for a nonsimple material with a center of symmetry is
considered. In the linear case, the well-posedness with and without
Kelvin-Voigt and/or frictional damping in the elastic part as well as the lack
of exponential stability in the elastically undamped case is proved. Further, a
frictional damping for the elastic component is shown to lead to the
exponential stability. A Cattaneo-type hyperbolic relaxation for the thermal
part is introduced and the well-posedness and uniform stability under a
nonlinear frictional damping are obtained using a compactness-uniqueness-type
argument. Additionally, a connection between the exponential stability and
exact observability for unitary $C_{0}$-groups is established.


title:
An elementary purely algebraic approach to generalized functions and
  operational calculus

abstract:
  The space of Schwartz distributions of finite order is represented as a
factor space of the space of, what we call, Mikusinski functions. The point of
Mikusinski functions is that they admit a multiplication by convergent Laurent
series. It is shown that this multiplication provides a natural simple basis
for Heaviside's operational calculus.


title:
On the hardness of the Learning with Errors problem with a discrete
  reproducible error distribution

abstract:
  In this work we show that the hardness of the Learning with Errors problem
with errors taken from the discrete Gaussian distribution implies the hardness
of the Learning with Errors problem with errors taken from the symmetric
Skellam distribution. Due to the sample preserving search-to-decision reduction
by Micciancio and Mol the same result applies to the decisional version of the
problem. Thus, we provide a variant of the Learning with Errors problem that is
hard based on conjecturally hard lattice problems and uses a discrete error
distribution that is similar to the continuous Gaussian distribution in that it
is closed under convolution. As an application of this result we construct a
post-quantum cryptographic protocol for differentially private data anlysis in
the distributed model. The security of this protocol is based on the hardness
of the new variant of the Decisional Learning with Errors problem. A feature of
this protocol is the use of the same noise for security and for differential
privacy resulting in an efficiency boost.


title: Antiferromagnetism in trigonal SrMn2As2 and CaMn2As2 single crystals

abstract:
  Crystallographic, electronic transport, thermal and magnetic properties are
reported for SrMn2As2 and CaMn2As2 single crystals grown using Sn flux.
Rietveld refinements of powder x-ray diffraction data show that the two
compounds are isostructural and crystallize in the trigonal CaAl2Si2-type
structure (space group P-3m1), in agreement with the literature. Electrical
resistivity rho versus temperature T measurements demonstrate insulating ground
states for both compounds with activation energies of 85 meV for SrMn2As2 and
61 meV for CaMn2As2. In a local-moment picture, the Mn^{+2} 3d^5 ions are
expected to have high-spin S = 5/2 with spectroscopic splitting factor g = 2.
Magnetic susceptibility chi and heat capacity measurements versus T reveal
antiferromagnetic (AFM) transitions at TN = 120(2) K and 62(3) K for SrMn2As2
and CaMn2As2, respectively. The anisotropic chi(T < TN) data indicate that the
hexagonal c axis is the hard axis and hence that the ordered Mn moments are
aligned in the ab plane. The chi(T) for both compounds and Cp(T) data for
SrMn2As2 show strong dynamic short-range AFM correlations from TN up to at
least 900 K, likely associated with quasi-two-dimensional connectivity of
strong AFM exchange interactions between the Mn spins within the corrugated
honeycomb Mn layers parallel to the ab plane.


title: Topological Protection of Photonic Path Entanglement

abstract:
  The recent advent of photonic topological insulators has opened the door to
using the robustness of topologically protected transport (originated in the
domain of condensed matter physics) in optical devices and in quantum
simulation. Concurrently, quantum walks in photonic networks have been shown to
yield exponential speedup for certain algorithms, such as Boson sampling. Here
we theoretically demonstrate that photonic topological insulators can robustly
protect the transport of quantum information through photonic networks, despite
the presence of disorder.


title: Revenue Maximization and Ex-Post Budget Constraints

abstract:
  We consider the problem of a revenue-maximizing seller with m items for sale
to n additive bidders with hard budget constraints, assuming that the seller
has some prior distribution over bidder values and budgets. The prior may be
correlated across items and budgets of the same bidder, but is assumed
independent across bidders. We target mechanisms that are Bayesian Incentive
Compatible, but that are ex-post Individually Rational and ex-post budget
respecting. Virtually no such mechanisms are known that satisfy all these
conditions and guarantee any revenue approximation, even with just a single
item. We provide a computationally efficient mechanism that is a
$3$-approximation with respect to all BIC, ex-post IR, and ex-post budget
respecting mechanisms. Note that the problem is NP-hard to approximate better
than a factor of 16/15, even in the case where the prior is a point mass
\cite{ChakrabartyGoel}. We further characterize the optimal mechanism in this
setting, showing that it can be interpreted as a distribution over virtual
welfare maximizers.
  We prove our results by making use of a black-box reduction from mechanism to
algorithm design developed by \cite{CaiDW13b}. Our main technical contribution
is a computationally efficient $3$-approximation algorithm for the algorithmic
problem that results by an application of their framework to this problem. The
algorithmic problem has a mixed-sign objective and is NP-hard to optimize
exactly, so it is surprising that a computationally efficient approximation is
possible at all. In the case of a single item ($m=1$), the algorithmic problem
can be solved exactly via exhaustive search, leading to a computationally
efficient exact algorithm and a stronger characterization of the optimal
mechanism as a distribution over virtual value maximizers.


title:
Secrecy Rate Maximization for MISO Multicasting SWIPT System with Power
  Splitting Scheme

abstract:
  This paper considers transmit covariance matrix design for secrecy rate
maximization problem in a multiple-input single-output (MISO) multicasting
simultaneous wireless information and power transfer (SWIPT) system. In order
to enhance the performance of the system, artificial noise (AN) is added to the
transmit signal in the design for the following purposes: to reduce the
received signal-to-noise ratio (SNR) at the eavesdroppers and increase the
harvested energy. We assume that all the channel-state-information (CSI) is
perfectly known at the transmitter and all legitimate users are capable of
simultaneously receiving information and harvesting energy. In addition, all
the eavesdroppers are passive and they can harvest energy only when they are
not intercepting or eavesdropping the messages intended for the legitimate
users. The original secrecy rate maximization problem is not convex in terms of
transmit and artificial covariance matrices as well as the power splitting (PS)
ratio. In order to circumvent this non-convexity issue, we exploit the
\emph{Charnes-Cooper} Transformation and semidefinite relaxation (SDR) to
convert this original problem into a convex one. However, this convex problem
does not always yield the rank-one transmit and AN covariance matrices to
obtain the solution of the original problem. Therefore, we analyze the optimal
conditions and utilize a Gaussian randomization (GR) method to construct the
rank-one solutions from the non-rank one results. Simulation results have been
provided to demonstrate the performance of the proposed transmit covariance
matrices design for MISO multicasting SWIPT system.


title: Q-balls in the Wick-Cutkosky model

abstract:
  In the present paper Q-ball solutions in the Wick--Cutkosky model are
examined in detail. A remarkable feature of the Wick--Cutkosky model is that it
admits analytical treatment for the most part of the analysis of Q-balls, which
allows one to use this simple model to demonstrate some peculiar properties of
Q-balls. In particular, a method for estimating the binding energy of a Q-ball
is proposed. This method is tested on the Wick--Cutkosky model taking into
account the well-known results obtained for this model earlier.


title:
Robust Bayesian Method for Simultaneous Block Sparse Signal Recovery
  with Applications to Face Recognition

abstract:
  In this paper, we present a novel Bayesian approach to recover simultaneously
block sparse signals in the presence of outliers. The key advantage of our
proposed method is the ability to handle non-stationary outliers, i.e. outliers
which have time varying support. We validate our approach with empirical
results showing the superiority of the proposed method over competing
approaches in synthetic data experiments as well as the multiple measurement
face recognition problem.


title: Quasinormal frequencies of black hole in the braneworld

abstract:
  We have studied scalar, electromagnetic and gravitational perturbations of
the four-dimensional Reissner-Nordstr\"{o}m-like black holes with a
\textit{tidal charge} in the Randall-Sundrum braneworld. The quasinormal modes
of these scalar, electromagnetic, as well as axial and polar gravitational
perturbations, have been studied in both normal and eikonal regimes.
Calculations have shown that the black holes on the Randall-Sundrum brane are
stable against scalar, electromagnetic and gravitational perturbations.
Moreover, we determine the grey body factor, giving transmission and reflection
of the scattered waves through the scalar, electromagnetic and gravitational
effective potentials. It has been shown that the scalar perturbative fields are
the most favorite to the reflected as compared to the latter. With increasing
value of the tidal charge ability of the all perturbative potentials to reflect
the waves decreases. Our calculations in low- and high-frequency regimes have
shown that black holes on the braneworld always have a bigger absorption cross
section of massless scalar waves than the Schwarzschild and standard
Reissner-Nordstr\"{o}m black holes.


title:
Resummation of Goldstone boson contributions to the MSSM effective
  potential

abstract:
  We discuss the resummation of the Goldstone boson contributions to the
effective potential of the Minimal Supersymmetric Standard Model (MSSM). This
eliminates the formal problems of spurious imaginary parts and logarithmic
singularities in the minimization conditions when the tree-level Goldstone
boson squared masses are negative or approach zero. The numerical impact of the
resummation is shown to be almost always very small. We also show how to write
the two-loop minimization conditions so that Goldstone boson squared masses do
not appear at all, and so that they can be solved without iteration.


title:
Deformably Registering and Annotating Whole CLARITY Brains to an Atlas
  via Masked LDDMM

abstract:
  The CLARITY method renders brains optically transparent to enable
high-resolution imaging in the structurally intact brain. Anatomically
annotating CLARITY brains is necessary for discovering which regions contain
signals of interest. Manually annotating whole-brain, terabyte CLARITY images
is difficult, time-consuming, subjective, and error-prone. Automatically
registering CLARITY images to a pre-annotated brain atlas offers a solution,
but is difficult for several reasons. Removal of the brain from the skull and
subsequent storage and processing cause variable non-rigid deformations, thus
compounding inter-subject anatomical variability. Additionally, the signal in
CLARITY images arises from various biochemical contrast agents which only
sparsely label brain structures. This sparse labeling challenges the most
commonly used registration algorithms that need to match image histogram
statistics to the more densely labeled histological brain atlases. The standard
method is a multiscale Mutual Information B-spline algorithm that dynamically
generates an average template as an intermediate registration target. We
determined that this method performs poorly when registering CLARITY brains to
the Allen Institute's Mouse Reference Atlas (ARA), because the image histogram
statistics are poorly matched. Therefore, we developed a method (Mask-LDDMM)
for registering CLARITY images, that automatically find the brain boundary and
learns the optimal deformation between the brain and atlas masks. Using
Mask-LDDMM without an average template provided better results than the
standard approach when registering CLARITY brains to the ARA. The LDDMM
pipelines developed here provide a fast automated way to anatomically annotate
CLARITY images. Our code is available as open source software at
http://NeuroData.io.


title: A holographic model for black hole complementarity

abstract:
  We explore a version of black hole complementarity, where an approximate
semiclassical effective field theory for interior infalling degrees of freedom
emerges holographically from an exact evolution of exterior degrees of freedom.
The infalling degrees of freedom have a complementary description in terms of
outgoing Hawking radiation and must eventually decohere with respect to the
exterior Hamiltonian, leading to a breakdown of the semiclassical description
for an infaller. Trace distance is used to quantify the difference between the
complementary time evolutions, and to define a decoherence time. We propose a
dictionary where the evolution with respect to the bulk effective Hamiltonian
corresponds to mean field evolution in the holographic theory. In a particular
model for the holographic theory, which exhibits fast scrambling, the
decoherence time coincides with the scrambling time. The results support the
hypothesis that decoherence of the infalling holographic state and disruptive
bulk effects near the curvature singularity are complementary descriptions of
the same physics, which is an important step toward resolving the black hole
information paradox.


title:
Attack Resilience and Recovery using Physical Challenge Response
  Authentication for Active Sensors Under Integrity Attacks

abstract:
  Embedded sensing systems are pervasively used in life- and security-critical
systems such as those found in airplanes, automobiles, and healthcare.
Traditional security mechanisms for these sensors focus on data encryption and
other post-processing techniques, but the sensors themselves often remain
vulnerable to attacks in the physical/analog domain. If an adversary
manipulates a physical/analog signal prior to digitization, no amount of
digital security mechanisms after the fact can help. Fortunately, nature
imposes fundamental constraints on how these analog signals can behave. This
work presents PyCRA, a physical challenge-response authentication scheme
designed to protect active sensing systems against physical attacks occurring
in the analog domain. PyCRA provides security for active sensors by continually
challenging the surrounding environment via random but deliberate physical
probes. By analyzing the responses to these probes, and by using the fact that
the adversary cannot change the underlying laws of physics, we provide an
authentication mechanism that not only detects malicious attacks but provides
resilience against them. We demonstrate the effectiveness of PyCRA through
several case studies using two sensing systems: (1) magnetic sensors like those
found wheel speed sensors in robotics and automotive, and (2) commercial RFID
tags used in many security-critical applications. Finally, we outline methods
and theoretical proofs for further enhancing the resilience of PyCRA to active
attacks by means of a confusion phase---a period of low signal to noise ratio
that makes it more difficult for an attacker to correctly identify and respond
to PyCRA's physical challenges. In doing so, we evaluate both the robustness
and the limitations of PyCRA, concluding by outlining practical considerations
as well as further applications for the proposed authentication mechanism.