title: Single-shot security for one-time memories in the isolated qubits model

abstract:
  One-time memories (OTM's) are simple, tamper-resistant cryptographic devices,
which can be used to implement sophisticated functionalities such as one-time
programs. Can one construct OTM's whose security follows from some physical
principle? This is not possible in a fully-classical world, or in a
fully-quantum world, but there is evidence that OTM's can be built using
"isolated qubits" -- qubits that cannot be entangled, but can be accessed using
adaptive sequences of single-qubit measurements.
  Here we present new constructions for OTM's using isolated qubits, which
improve on previous work in several respects: they achieve a stronger
"single-shot" security guarantee, which is stated in terms of the (smoothed)
min-entropy; they are proven secure against adversaries who can perform
arbitrary local operations and classical communication (LOCC); and they are
efficiently implementable.
  These results use Wiesner's idea of conjugate coding, combined with
error-correcting codes that approach the capacity of the q-ary symmetric
channel, and a high-order entropic uncertainty relation, which was originally
developed for cryptography in the bounded quantum storage model.


title: Branching Bisimilarity Checking for PRS

abstract:
  Recent studies reveal that branching bisimilarity is decidable for both nBPP
(normed Basic Parallel Process) and nBPA (normed Basic Process Algebra). These
results lead to the question if there are any other models in the hierarchy of
PRS (Process Rewrite System) whose branching bisimilarity is decidable. It is
shown in this paper that the branching bisimilarity for both nOCN (normed One
Counter Net) and nPA (normed Process Algebra) is undecidable. These results
essentially imply that the question has a negative answer.


title:
Distributed Algorithms for Stochastic Source Seeking with Mobile Robot
  Networks: Technical Report

abstract:
  Autonomous robot networks are an effective tool for monitoring large-scale
environmental fields. This paper proposes distributed control strategies for
localizing the source of a noisy signal, which could represent a physical
quantity of interest such as magnetic force, heat, radio signal, or chemical
concentration. We develop algorithms specific to two scenarios: one in which
the sensors have a precise model of the signal formation process and one in
which a signal model is not available. In the model-free scenario, a team of
sensors is used to follow a stochastic gradient of the signal field. Our
approach is distributed, robust to deformations in the group geometry, does not
necessitate global localization, and is guaranteed to lead the sensors to a
neighborhood of a local maximum of the field. In the model-based scenario, the
sensors follow the stochastic gradient of the mutual information between their
expected measurements and the location of the source in a distributed manner.
The performance is demonstrated in simulation using a robot sensor network to
localize the source of a wireless radio signal.


title:
Performance of the Survey Propagation-guided decimation algorithm for
  the random NAE-K-SAT problem

abstract:
  We show that the Survey Propagation-guided decimation algorithm fails to find
satisfying assignments on random instances of the "Not-All-Equal-$K$-SAT"
problem if the number of message passing iterations is bounded by a constant
independent of the size of the instance and the clause-to-variable ratio is
above $(1+o_K(1)){2^{K-1}\over K}\log^2 K$ for sufficiently large $K$. Our
analysis in fact applies to a broad class of algorithms described as
"sequential local algorithms". Such algorithms iteratively set variables based
on some local information and then recurse on the reduced instance. Survey
Propagation-guided as well as Belief Propagation-guided decimation algorithms -
two widely studied message passing based algorithms, fall under this category
of algorithms provided the number of message passing iterations is bounded by a
constant. Another well-known algorithm falling into this category is the Unit
Clause algorithm. Our work constitutes the first rigorous analysis of the
performance of the SP-guided decimation algorithm.
  The approach underlying our paper is based on an intricate geometry of the
solution space of random NAE-$K$-SAT problem. We show that above the
$(1+o_K(1)){2^{K-1}\over K}\log^2 K$ threshold, the overlap structure of
$m$-tuples of satisfying assignments exhibit a certain clustering behavior
expressed in the form of constraints on distances between the $m$ assignments,
for appropriately chosen $m$. We further show that if a sequential local
algorithm succeeds in finding a satisfying assignment with probability bounded
away from zero, then one can construct an $m$-tuple of solutions violating
these constraints, thus leading to a contradiction. Along with (citation), this
result is the first work which directly links the clustering property of random
constraint satisfaction problems to the computational hardness of finding
satisfying assignments.

categories: math.PR cond-mat.stat-mech cs.AI cs.CC cs.DS math.CO


title:
Physically motivated exploration of the extrinsic parameter space in
  ground-based gravitational-wave astronomy

abstract:
  Efficient parameter estimation is critical for Gravitational-Wave astronomy.
In the case of compact binary coalescence, the high dimensional parameter space
demands efficient sampling techniques - such as Markov chain Monte Carlo
(MCMC). A number of degeneracies effectively reduce the dimensionality of the
parameter space and, when known, can render sampling algorithms more efficient
with problem-specific improvements. We present in this paper an analytical
description of a degeneracy involving the extrinsic parameters of a compact
binary coalescence gravitational-wave signal, when data from a three detector
network (such as Advanced LIGO/Virgo) is available. We use this new formula to
construct a jump proposal, a framework for a generic sampler to take advantage
of the degeneracy. We show the gain in efficiency for a MCMC sampler in the
analysis of the gravitational-wave signal from a compact binary coalescence.


title: Popular conjectures imply strong lower bounds for dynamic problems

abstract:
  We consider several well-studied problems in dynamic algorithms and prove
that sufficient progress on any of them would imply a breakthrough on one of
five major open problems in the theory of algorithms:
  1. Is the 3SUM problem on $n$ numbers in $O(n^{2-\epsilon})$ time for some
$\epsilon>0$?
  2. Can one determine the satisfiability of a CNF formula on $n$ variables in
$O((2-\epsilon)^n poly n)$ time for some $\epsilon>0$?
  3. Is the All Pairs Shortest Paths problem for graphs on $n$ vertices in
$O(n^{3-\epsilon})$ time for some $\epsilon>0$?
  4. Is there a linear time algorithm that detects whether a given graph
contains a triangle?
  5. Is there an $O(n^{3-\epsilon})$ time combinatorial algorithm for $n\times
n$ Boolean matrix multiplication?
  The problems we consider include dynamic versions of bipartite perfect
matching, bipartite maximum weight matching, single source reachability, single
source shortest paths, strong connectivity, subgraph connectivity, diameter
approximation and some nongraph problems such as Pagh's problem defined in a
recent paper by Patrascu [STOC 2010].


title: On the Ground State Wave Function of Matrix Theory

abstract:
  We propose an explicit construction of the leading terms in the asymptotic
expansion of the ground state wave function of BFSS SU(N) matrix quantum
mechanics. Our proposal is consistent with the expected factorization property
in various limits of the Coulomb branch, and involves a different scaling
behavior from previous suggestions. We comment on some possible physical
implications.


title: Structural defects induced by Fe-ion implantation in TiO2

abstract:
  X-ray photoelectron spectroscopy (XPS) and resonant x-ray emission
spectroscopy (RXES) measurements of pellet and thin film forms of TiO$_2$ with
implanted Fe ions are presented and discussed. The findings indicate that
Fe-implantation in a TiO$_2$ pellet sample induces heterovalent cation
substitution (Fe$^{2+}\rightarrow$ Ti$^{4+}$) beneath the surface region. But
in thin film samples, the clustering of Fe atoms is primarily detected. In
addition to this, significant amounts of secondary phases of Fe$^{3+}$ are
detected on the surface of all doped samples due to oxygen exposure. These
experimental findings are compared with density functional theory (DFT)
calculations of formation energies for different configurations of structural
defects in the implanted TiO$_2$:Fe system. According to our calculations, the
clustering of Fe-atoms in TiO$_2$:Fe thin films can be attributed to the
formation of combined substitutional and interstitial defects. Further, the
differences due to Fe doping in pellet and thin film samples can ultimately be
attributed to different surface to volume ratios.


title: Bosonic (p - 1)-forms in Einstein-Cartan theory of gravity

abstract:
  We introduce bosonic (p - 1)-form fields that couple to the spin connection
of the Einstein-Cartan theory of gravity thus becoming a non-trivial source of
space-time torsion. We analyze all the general features of both the matter and
the gravitational sectors of the theory. Finally we briefly consider the
implications of the existence of such fields in different physical settings.


title:
Water Purification by Shock Electrodialysis: Deionization, Filtration,
  Separation, and Disinfection

abstract:
  The development of energy and infrastructure efficient water purification
systems are among the most critical engineering challenges facing our society.
Water purification is often a multi-step process involving filtration,
desalination, and disinfection of a feedstream. Shock electrodialysis (shock
ED) is a newly developed technique for water desalination, leveraging the
formation of ion concentration polarization (ICP) zones and deionization shock
waves in microscale pores near to an ion selective element. While shock ED has
been demonstrated as an effective water desalination tool, we here present
evidence of other simultaneous functionalities. We show that, unlike
electrodialysis, shock ED can thoroughly filter micron-scale particles and
aggregates of nanoparticles present in the feedwater. We also demonstrate that
shock ED can enable disinfection of feedwaters, as approximately $99\%$ of
viable bacteria (here \textit{E. coli}) in the inflow were killed or removed by
our prototype. Shock ED also separates positive from negative particles,
contrary to claims that ICP acts as a virtual barrier for all charged
particles. By combining these functionalities (filtration, separation and
disinfection) with deionization, shock ED has the potential to enable more
compact and efficient water purification systems.


title: Lie, symplectic and Poisson groupoids and their Lie algebroids

abstract:
  Groupoids are mathematical structures able to describe symmetry properties
more general than those described by groups. They were introduced (and named)
by H. Brandt in 1926. Around 1950, Charles Ehresmann used groupoids with
additional structures (topological and differentiable) as essential tools in
topology and differential geometry. In recent years, Mickael Karasev, Alan
Weinstein and Stanis{\l}aw Zakrzewski independently discovered that symplectic
groupoids can be used for the construction of noncommutative deformations of
the algebra of smooth functions on a manifold, with potential applications to
quantization. Poisson groupoids were introduced by Alan Weinstein as
generalizations of both Poisson Lie groups and symplectic groupoids. We present
here the main definitions and first properties relative to groupoids, Lie
groupoids, Lie algebroids, symplectic and Poisson groupoids and their Lie
algebroids.


title: On Classification of Toric Surface Codes of Low Dimension

abstract:
  This work is a natural continuation of our previous work \cite{yz}. In this
paper, we give a complete classification of toric surface codes of dimension
less than or equal to 6, except a special pair, $C_{P_6^{(4)}}$ and
$C_{P_6^{(5)}}$ over $\mathbb{F}_8$. Also, we give an example, $C_{P_6^{(5)}}$
and $C_{P_6^{(6)}}$ over $\mathbb{F}_7$, to illustrate that two monomially
equivalent toric codes can be constructed from two lattice non-equivalent
polygons.


title: Parafermions in the tau-2 model

abstract:
  It has been shown recently by Baxter that the $\tau_2(t_q)$ model with open
boundary conditions can be solved by the "parafermionic" method of Fendley. In
Baxter's paper there are several conjectures, which were formulated based on
numerical short-chain calculations. Here we present the proof of two of them.


title: Exact Common Information

abstract:
  This paper introduces the notion of exact common information, which is the
minimum description length of the common randomness needed for the exact
distributed generation of two correlated random variables $(X,Y)$. We introduce
the quantity $G(X;Y)=\min_{X\to W \to Y} H(W)$ as a natural bound on the exact
common information and study its properties and computation. We then introduce
the exact common information rate, which is the minimum description rate of the
common randomness for the exact generation of a 2-DMS $(X,Y)$. We give a
multiletter characterization for it as the limit $\bar{G}(X;Y)=\lim_{n\to
\infty}(1/n)G(X^n;Y^n)$. While in general $\bar{G}(X;Y)$ is greater than or
equal to the Wyner common information, we show that they are equal for the
Symmetric Binary Erasure Source. We do not know, however, if the exact common
information rate has a single letter characterization in general.


title: Phase Shift Analysis of Elastic n3He Scattering

abstract:
  Basing on the kwon experimental measurements of differential cross sections
on n3He elastic scattering in the angular energy range 200 - 1600 the standard
phase shifts analysis was performed at the energies from 1 MeV up to 5 MeV.


title: High order schemes for the tempered fractional diffusion equations

abstract:
  L\'{e}vy flight models whose jumps have infinite moments are mathematically
used to describe the superdiffusion in complex systems. Exponentially tempering
the Levy measure of L\'{e}vy flights leads to the tempered stable L\'{e}vy
processes which combine both the $\alpha$-stable and Gaussian trends; and the
very large jumps are unlikely and all their moments exist. The probability
density functions of the tempered stable L\'{e}vy processes solve the tempered
fractional diffusion equation. This paper focuses on designing the high order
difference schemes for the tempered fractional diffusion equation on bounded
domain. The high order difference approximations, called the tempered and
weighted and shifted Gr\"{u}nwald difference (tempered-WSGD) operators, in
space are obtained by using the properties of the tempered fractional calculus
and weighting and shifting their first order Gr\"{u}nwald type difference
approximations. And the Crank-Nicolson discretization is used in the time
direction. The stability and convergence of the presented numerical schemes are
established; and the numerical experiments are performed to confirm the
theoretical results and testify the effectiveness of the schemes.


title: On an arithmetic convolution

abstract:
  The Cauchy-type product of two arithmetic functions $f$ and $g$ on
nonnegative integers is defined as $(f\bullet g)(k):=\sum_{m=0}^{k} {k\choose
m}f(m)g(k-m)$. We explore some algebraic properties of the aforementioned
convolution, which is a fundamental-characteristic of the identities involving
the Bernoulli numbers, the Bernoulli polynomials, the power sums, the sums of
products, henceforth.


title: On the quenching behavior of the MEMS with fringing field

abstract:
  The singular parabolic problem $u_t-\triangle u=\lambda{\frac{1+\delta|\nabla
u|^2}{(1-u)^2}}$ on a bounded domain $\Omega$ of $\mathbb{R}^n$ with Dirichlet
boundary condition, models the Microelectromechanical systems (MEMS) device
with fringing field. In this paper, we focus on the quenching behavior of the
solution to this equation. We first show that there exists a critical value
$\lambda_\delta^*>0$ such that if $0<\lambda<\lambda_\delta^*$, all solutions
exist globally; while for $\lambda>\lambda_\delta^*$, all the solution will
quench in finite time. The estimate of the quenching time in terms of large
voltage $\lambda$ is investigated. Furthermore, the quenching set is a compact
subset of $\Omega$, provided $\Omega$ is a convex bounded domain in
$\mathbb{R}^n$. In particular, if the domain $\Omega$ is radially symmetric,
then the origin is the only quenching point. We not only derive the one-side
estimate of the quenching rate, but also further study the refined asymptotic
behavior of the finite quenching solution.


title: Unfriendly or weakly unfriendly partitions of graphs

abstract:
  For each infinite cardinal $\kappa $ and each graph $G=(V,E)$, we say that a
partition $\pi :V\rightarrow \left\{ 0,1\right\} $ is $\kappa $-unfriendly if,
for each $x\in V$, $\left| \left\{ y\in V\mid \left\{ x,y\right\} \in E\text{
and }\pi (y)\neq \pi (x)\right\} \right| $ is $\geq \left| \left\{ y\in V\mid
\left\{ x,y\right\} \in E\text{ and }\pi (y)=\pi (x)\right\} \right| $ or $\geq
\kappa $; $\pi $ is unfriendly if the first property is true for each $x\in V$.
Some uncountable graphs of infinite minimum degree without unfriendly partition
have been constructed by S. Shelah and E.C. Milner, but it is not presently
known if countable graphs without unfriendly partition exist. We show that, for
each integer $n$, each graph of infinite minimum degree has an $\omega
_{n}$-unfriendly partition. We also prove that the following properties are
equivalent: (i) each graph has an $\omega $-unfriendly partition; (ii) each
countable graph has an unfriendly partition; (iii) each countable graph without
nonempty induced subgraph of infinite minimum degree has an unfriendly
partition (actually it is enough to consider a smaller class of graphs).


title: Radiation Pattern of Patch Antenna with Slits

abstract:
  The Microstrip antenna has been commercially used in many applications, such
as direct broadcast satellite service, mobile satellite communications, global
positioning system, medical hyperthermia usage, etc. The patch antenna of the
size reduction at a given operating frequency is obtained. Mobile personal
communication systems and wireless computer networks are most commonly used
nowadays and they are in need of antennas in different frequency bands. In
regulate to without difficulty incorporate these antennas into individual
systems, a micro strip scrap transmitter have been preferred and intended for a
convinced divergence. There is also an analysis of radiation pattern, Gain of
the antenna, Directivity of the antenna, Electric Far Field. The simulations
results are obtained by using electromagnetic simulation software called feko
software are presented and discussed


title:
Multivariate Spectral Estimation based on the concept of Optimal
  Prediction

abstract:
  In this technical note, we deal with a spectrum approximation problem arising
in THREE-like multivariate spectral estimation approaches. The solution to the
problem minimizes a suitable divergence index with respect to an a priori
spectral density. We derive a new divergence family between multivariate
spectral densities which takes root in the prediction theory. Under mild
assumptions on the a priori spectral density, the approximation problem, based
on this new divergence family, admits a family of solutions. Moreover, an upper
bound on the complexity degree of these solutions is provided.


title: Generic area-preserving reversible diffeomorphisms

abstract:
  Let M be a surface and R an involution in M whose set of fixed points is a
submanifold with dimension 1 and such that R is an isometry. We will show that
there is a residual subset of C1 area-preserving R-reversible diffeomorphisms
which are either Anosov or have zero Lyapunov exponents at almost every point.


title:
Local measurement of the Eliashberg function of Pb islands: enhancement
  of electron-phonon coupling by quantum well states

abstract:
  Inelastic tunneling spectroscopy of Pb islands on Cu(111) obtained by
scanning tunneling microscopy below 1K provides a direct access to the local
Eliashberg function of the islands with high energy resolution. The Eliashberg
function describes the electron-phonon interaction causing conventional
superconductivity. The measured Eliashberg function strongly depends on the
local thickness of the Pb nanostructures and shows a sharp maximum when quantum
well states of the Pb islands come close to the Fermi energy. Ab initio
calculations reveal that this is related to enhanced electron-phonon coupling
at these thicknesses.


title: Induced Representations and Hypergroupoids

abstract:
  We review various notions of correspondences for locally compact groupoids
with Haar systems, in particular a recent definition due to R.D. Holkar. We
give the construction of the representations induced by such a correspondence.
Finally, we extend the construction of induced representations to
hypergroupoids.


title:
Fluctuations and Flares in the Ultraviolet Line Emission of Cool Stars:
  Implications for Exoplanet Transit Observations

abstract:
  Variations in stellar flux can potentially overwhelm the photometric signal
of a transiting planet. Such variability has not previously been
well-characterized in the ultraviolet lines used to probe the inflated
atmospheres surrounding hot Jupiters. Therefore, we surveyed 38 F-M stars for
intensity variations in four narrow spectroscopic bands: two enclosing strong
lines from species known to inhabit hot Jupiter atmospheres, CII
$\lambda\lambda$1334,1335 and SiIII $\lambda$1206; one enclosing SiIV
$\lambda\lambda$1393,1402; and 36.5 angstroms of interspersed continuum. For
each star/band combination, we generated 60 s cadence lightcurves from archival
HST COS and STIS time-tagged photon data. Within these lightcurves, we
characterized flares and stochastic fluctuations as separate forms of
variability. Flares: We used a cross-correlation approach to detect 116 flares.
These events occur in the time-series an average of once per 2.5 h, over 50%
last 4 min or less, and most produce the strongest response in SiIV. If the
flare occurred during a transit measurement integrated for 60 min, 90/116 would
destroy the signal of an Earth, 27/116 Neptune, and 7/116 Jupiter, with the
upward bias in flux ranging from 1-109% of quiescent levels. Fluctuations:
Photon noise and underlying stellar fluctuations produce scatter in the
quiescent data. We model the stellar fluctuations as Gaussian white noise with
standard deviation $\sigma_x$. Maximum likelihood values of $\sigma_x$ range
from 1-41% for 60 s measurements. These values suggest that many cool stars
will only permit a transit detection to high confidence in ultraviolet
resonance lines if the radius of the occulting disk is $\gtrsim$ 1 R$_J$.
However, for some M dwarfs this limit can be as low as several $R_{Earth}$.


title:
A simple construction of indecomposable higher Chow cycles in elliptic
  surfaces

abstract:
  I construct regulator indecomposable higher Chow cycles in elliptic surfaces
satisfying certain conditions. As an application I give an alternative proof of
a theorem of Gordon and Lewis, which asserts that there is a real regulator
indecomposable cycles in a product of general elliptic curves.


title:
Galaxy luminosity function and its cosmological evolution: Testing a new
  feedback model depending on galaxy-scale dust opacity

abstract:
  We present a new version of a semi-analytic model of cosmological galaxy
formation, incorporating a star formation law with a feedback depending on the
galaxy-scale mean dust opacity and metallicity, motivated by recent
observations of star formation in nearby galaxies and theoretical
considerations. This new model is used to investigate the effect of such a
feedback on shaping the galaxy luminosity function and its evolution. Star
formation activity is significantly suppressed in dwarf galaxies by the new
feedback effect, and the faint-end slope of local luminosity functions can be
reproduced with a reasonable strength of supernova feedback, which is in
contrast to the previous models that require a rather extreme strength of
supernova feedback. Our model can also reproduce the early appearance of
massive galaxies manifested in the bright-end of high redshift K-band
luminosity functions. Though some of the previous models also succeeded in
reproducing this, they assumed a star formation law depending on the
galaxy-scale dynamical time, which is not supported by observations. We argue
that the feedback depending on dust opacity (or metal column density) is
essential, rather than that simply depending on gas column density, to get
these results.


title:
Normal Form and Energy Conservation of High Frequency Subsystems Without
  Nonresonance Conditions

abstract:
  We consider a system in which some high frequency harmonic oscillators are
coupled with a slow system. We prove that up to very long times the energy of
the high frequency system changes only by a small amount. The result we obtain
is completely independent of the resonance relations among the frequencies of
the fast system. More in detail, denote by $\epsilon^{-1}$ the smallest high
frequency. In the first part of the paper we apply the main result of [BG93] to
prove almost conservation of the energy of the high frequency system over times
exponentially long with $ {\epsilon^{-1/n}} $ ($n$ being the number of fast
oscillators). In the second part of the paper we give e new self-contained
proof of a similar result which however is valid only over times of order
$\epsilon^{-N}$ with an arbitrary $N$. Such a second result is very similar to
the main result of the paper [GHL13], which actually was the paper which
stimulated our work.


title:
Effects of stellar flybys on planetary systems: 3D modeling of the
  circumstellar disks damping effects

abstract:
  Stellar flybys in star clusters are suspected to affect the orbital
architecture of planetary systems causing eccentricity excitation and orbital
misalignment between the planet orbit and the equatorial plane of the star. We
explore whether the impulsive changes in the orbital elements of planets,
caused by an hyperbolic stellar flyby, can be fully damped by the circumstellar
disk surrounding the star. The time required to disperse stellar clusters is in
fact comparable to circumstellar disk's lifetime. We have modelled in 3D a
system made of a solar type star surrounded by a low density disk with a giant
planet embedded in it approached on a hyperbolic encounter trajectory by a
second star, of similar mass and with its own disk. We focus on extreme
configurations where a very deep stellar flyby perturbs a Jovian planet on an
external orbit. This allows to test in full the ability of the disk to erase
the effects of the stellar encounter. We find that the amount of mass lost by
the disk during the stellar flyby is less than in 2D models where a single disk
was considered due to the mass exchange between the two disks at the encounter.
The damping in eccentricity is slightly faster than in 2D models and it occurs
on timescales of the order of a few kyr. The only trace of the flyby left in
the planet system, after about 10^4 yr, is a small misalignment, lower than 9
degrees, between the star equatorial plane and the planet orbit. In a realistic
model based on 3D simulations of star--planet--disk interactions, we find that
stellar flybys cannot excite significant eccentricities and inclinations of
planets in stellar clusters. The circumstellar disks hosting the planets damp
on a short timescale all the step changes in the two orbital parameters
produced during any stellar encounter. All records of past encounters are
erased.


title:
The Complex Distribution of Recently Formed Stars. Bimodal Stellar
  Clustering in the Star-Forming Region NGC 346

abstract:
  We present a detailed stellar clustering analysis with the application of the
two-point correlation function on distinct young stellar ensembles. Our aim is
to understand how stellar systems are assembled at the earliest stages of their
formation. Our object of interest is the star-forming region NGC 346 in the
Small Magellanic Cloud. It is a young stellar system well-revealed from its
natal environment, comprising complete samples of pre--main-sequence and upper
main-sequence stars, very close to their formation. We apply a comprehensive
characterization of the autocorrelation function for both centrally condensed
stellar clusters and self-similar stellar distributions through numerical
simulations of stellar ensembles. We interpret the observed autocorrelation
function of NGC 346 on the basis of these simulations. We find that it can be
best explained as the combination of two distinct stellar clustering designs, a
centrally concentrated, dominant at the central part of the star-forming
region, and an extended self-similar distribution of stars across the complete
observed field. The cluster component, similar to non-truncated young star
clusters, is determined to have a core radius of ~2.5 pc and a density profile
index of ~2.3. The extended fractal component is found with our simulations to
have a fractal dimension of ~2.3, identical to that found for the interstellar
medium, in agreement to hierarchy induced by turbulence. This suggests that the
stellar clustering at a time very near to birth behaves in a complex manner. It
is the combined result of the star formation process regulated by turbulence
and the early dynamical evolution induced by the gravitational potential of
condensed stellar clusters.


title:
Study of Coherent Perfect Absorption Using Gaussian Beam in a Composite
  Medium

abstract:
  There is a study of coherent perfect absorption (CPA) in composite medium
(CM) which is made of metal-dielectric composition. The CM, an orthorhombic
shaped slab, is illuminated by two identical Gaussian beams (GB) incident at
equal angle of incidence and focused on the two interfaces between wall of slab
and air from opposite side. It has determine the necessary conditions required
for CPA and shows that perfect CPA is possible with GBs. Author also shows
broader beams exhibit more absorption than comparatively tightly focused beams.


title: Bilipschitz embedding of homogeneous fractals

abstract:
  In this paper, we introduce a class of fractals named homogeneous sets based
on some measure versions of homogeneity, uniform perfectness and doubling. This
fractal class includes all Ahlfors-David regular sets, but most of them are
irregular in the sense that they may have different Hausdorff dimensions and
packing dimensions. Using Moran sets as main tool, we study the dimensions,
bilipschitz embedding and quasi-Lipschitz equivalence of homogeneous fractals.


title: Proof Pattern Search in Coq/SSReflect

abstract:
  ML4PG is an extension of the Proof General interface, allowing the user to
invoke machine-learning algorithms and find proof similarities in Coq/SSReect
libraries. In this paper, we present three new improvements to ML4PG. First, a
new method of "recurrent clustering" is introduced to collect statistical
features from Coq terms. Now the user can receive suggestions about similar
definitions, types and lemma statements, in addition to proof strategies.
Second, Coq proofs are split into patches to capture proof strategies that
could arise at different stages of a proof. Finally, we improve ML4PG's output
introducing an automaton-shape representation for proof patterns.


title:
Electromagnetic Energy Conversion in Downstream Fronts from 3D Kinetic
  Reconnection

abstract:
  The electromagnetic energy equation is analyzed term by term in a 3D
simulation of kinetic reconnection previously reported by
\citet{vapirev2013formation}. The evolution presents the usual 2D-like
topological structures caused by an initial perturbation independent of the
third dimension. However, downstream of the reconnection site, where the
jetting plasma encounters the yet unperturbed pre-existing plasma, a downstream
front (DF) is formed and made unstable by the strong density gradient and the
unfavorable local acceleration field. The energy exchange between plasma and
fields is most intense at the instability, reaching several $pW/m^3$,
alternating between load (energy going from fields to particles) and generator
(energy going from particles to fields) regions. Energy exchange is instead
purely that of a load at the reconnection site itself in a region focused
around the x-line and elongated along the separatrix surfaces.
  Poynting fluxes are generated at all energy exchange regions and travel away
from the reconnection site transporting an energy signal of the order of about
$\mathbf S \approx 10^{-3} W/m^2$.

categories: physics.plasm-ph astro-ph.EP astro-ph.SR physics.space-ph


title: Infrared extinction in the Inner Milky Way through the red clump giants

abstract:
  While the shape of the extinction curve on the infrared is considered to be
set and the extinction ratios between infrared bands are usually taken to be
approximately constant, a recent number of studies point either to a spatially
variable behavior on the exponent of the power law or to a different extinction
law altogether. In this paper, we propose a method to analyze the overall
behavior of the interstellar extinction by means of the red-clump population,
and we apply it to those areas of the Milky Way where the presence of
interstellar matter is heavily felt: areas located in 5 deg<l<30 deg and b=0
deg. We show that the extinction ratios traditionally used for the near
infrared could be inappropriate for the inner Galaxy and we analyze the
behavior of the extinction law from 1 to 8 microns.


title:
Remarks on non-linear noise excitability of some stochastic heat
  equations

abstract:
  We consider nonlinear parabolic SPDEs of the form $\partial_t u=\Delta u +
\lambda \sigma(u)\dot w$ on the interval $(0, L)$, where $\dot w$ denotes
space-time white noise, $\sigma$ is Lipschitz continuous. Under Dirichlet
boundary conditions and a linear growth condition on $\sigma$, we show that the
expected $L^2$-energy is of order $\exp[\text{const}\times\lambda^4]$ as
$\lambda\rightarrow \infty$. This significantly improves a recent result of
Khoshnevisan and Kim. Our method is very different from theirs and it allows us
to arrive at the same conclusion for the same equation but with Neumann
boundary condition. This improves over another result of Khoshnevisan and Kim.


title: The Mass of the Black Hole in LMC X-3

abstract:
  We analyze a large set of new and archival photometric and spectroscopic
observations of LMC X-3 to arrive at a self-consistent dynamical model for the
system. Using echelle spectra obtained with the MIKE instrument on the 6.5m
Magellan Clay telescope and the UVES instrument on the second 8.2m Very Large
Telescope we find a velocity semiamplitude for the secondary star of
$K_2=241.1\pm 6.2$ km s$^{-1}$, where the uncertainty includes an estimate of
the systematic error caused by X-ray heating. Using the spectra, we also find a
projected rotational velocity of $V_{\rm rot}\sin i=118.5\pm 6.6$ km s$^{-1}$.
From an analysis of archival $B$ and $V$ light curves as well as new $B$ and
$V$ light curves from the SMARTS 1.3m telescope, we find an inclination of
$i=69.84\pm 0.37^{\circ}$ for models that do not include X-ray heating and an
inclination of $i=69.24\pm 0.72^{\circ}$ for models that incorporate X-ray
heating. Adopting the latter inclination measurement, we find masses of
$3.63\pm 0.57\,M_{\odot}$ and $6.98\pm 0.56\,M_{\odot}$ for the companion star
and the black hole, respectively. We briefly compare our results with earlier
work and discuss some of their implications.


title: A jetlet hierarchy for ideal fluid dynamics

abstract:
  Truncated Taylor expansions of smooth flow maps are used in Hamilton's
principle to derive a multiscale Lagrangian particle representation of ideal
fluid dynamics. Numerical simulations for scattering of solutions at one level
of truncation are found to produce solutions at higher levels. These scattering
events to higher levels in the Taylor expansion are interpreted as modeling a
cascade to smaller scales.


title: A novel datatype architecture support for programming languages

abstract:
  In programmers point of view, Datatypes in programming language level have a
simple description but inside hardware, huge machine codes are responsible to
describe type features. Datatype architecture design is a novel approach to
match programming features along with hardware design. In this paper a novel
Data type-Based Code Reducer (TYPELINE) architecture is proposed and
implemented according to significant data types (SDT) of programming languages.
TYPELINE uses TEUs for processing various SDT operations. This architecture
design leads to reducing the number of machine codes, and increases execution
speed, and also improves some parallelism level. This is because this
architecture supports some operation for the execution of Abstract Data Types
in parallel. Also it ensures to maintain data type features and entire
application level specifications using the proposed type conversion unit. This
framework includes compiler level identifying execution modes and memory
management unit for decreasing object read/write in heap memory by ISA support.
This energy-efficient architecture is completely compatible with object
oriented programming languages and in combination mode it can process complex
C++ data structures with respect to parallel TYPELINE architecture support.


title: New comments on "Possible divergences in Tsallis' thermostatistics''

abstract:
  In a recent letter ({\it{EPL}}, {\bf{104}} (2013) 60003; see also {\it
{arXiv:1309.5645}}), Plastino and Rocca suggest that the divergences inherent
to the formulation of nonextensive statistical mechanics can be eliminated {\it
{via}} the use of $q$-Laplace transformation which is illustrated for the case
of a kinetic Hamiltonian system, the harmonic oscillator. The suggested new
formulation raises questions which are discussed in the present comment.


title: Circular Geodesics in the Kerr-Newman-Taub-NUT Space-time

abstract:
  In this paper we investigate the equatorial causal (time-like and null)
circular geodesics of the Kerr-Newman-Taub-NUT(Newman-Unti-Tamburino) black
hole in four dimensional Lorentzian geometry. The special characteristics of
this black hole is that it is of \emph{Petrov-Pirani type D} and the photon
trajectories are \emph{doubly degenerate principal null congruence}. We derive
the conditions for existence of innermost stable circular orbit, marginally
bound circular orbit and circular photon orbit in the background of
Kerr-Newman-Taub-NUT(KNTN) space-time. The effective potential for both
time-like case and null cases have been studied. It is shown that the
\emph{presence of the NUT parameter deforms the shape of the effective
potential in contrast with the zero NUT parameter}. We further investigate the
energy extraction by the Penrose process for this space-time. It is shown that
the efficiency of this black hole depends on both the charge and NUT parameter.
It is observed that the energy gain is maximum when NUT parameter goes to zero
value and for the maximum spin value. When the value of NUT parameter is
increasing the energy-gain is decreasing.


title: The martingale approach after Varadhan and Dolgopyat

abstract:
  We present, in the simplest possible form, the so called martingale problem
strategy to establish limit theorems. The presentation is specially adapted to
problems arising in partially hyperbolic dynamical systems. We will discuss a
simple partially hyperbolic example with fast-slow variables and use the
martingale method to prove an averaging theorem and study fluctuations from the
average. The emphasis is on ideas rather than on results. Also, no effort
whatsoever is done to review the vast literature of the field.


title:
Some remarks on the staircasing phenomenon in total-variation based
  image denoising

abstract:
  This paper deals with the so-called staircasing phenomenon, which frequently
arises in total variation based denoising models in image analysis. We prove in
particular that staircasing always occurs at global extrema of the datum and at
all extrema of the minimizer. It is also shown that, for radial images, the
staircasing always appears at the extrema and at the boundary of the image. We
also prove the equivalence between the denoising model and the total variation
flow, in the radial case, thus extending a previous result in dimension one.
This equivalence cannot hold in the nonradial case, as it is shown with a
counterexample. This connection allows us to understand how the staircase zones
and the discontinuities of the denoising problem evolve with the regularization
parameter.


title: Mutual information of Contingency Tables and Related Inequalities

abstract:
  For testing independence it is very popular to use either the
$\chi^{2}$-statistic or $G^{2}$-statistics (mutual information). Asymptotically
both are $\chi^{2}$-distributed so an obvious question is which of the two
statistics that has a distribution that is closest to the
$\chi^{2}$-distribution. Surprisingly the distribution of mutual information is
much better approximated by a $\chi^{2}$-distribution than the
$\chi^{2}$-statistic. For technical reasons we shall focus on the simplest case
with one degree of freedom. We introduce the signed log-likelihood and
demonstrate that its distribution function can be related to the distribution
function of a standard Gaussian by inequalities. For the hypergeometric
distribution we formulate a general conjecture about how close the signed
log-likelihood is to a standard Gaussian, and this conjecture gives much more
accurate estimates of the tail probabilities of this type of distribution than
previously published results. The conjecture has been proved numerically in all
cases relevant for testing independence and further evidence of its validity is
given.


title: Stray capacitances in the watt balance operation: electrostatic forces

abstract:
  In a watt balance, stray capacitances exist between the coil and the magnet.
Since the electric current flowing in the coil originates a difference between
the coil and magnet electric-potentials, their electrostatic interactions must
be taken into account. This paper reports the results of a finite element
analysis of the forces acting on the coil.


title: EuNiGe3, an equal moment anisotropic antiferromagnet

abstract:
  Single crystals of EuNiGe$_3$ crystallizing in the non-centrosymmetric
BaNiSn$_3$-type structure have been grown using In flux, enabling us to explore
the anisotropic magnetic properties which was not possible with previously
reported polycrystalline samples. The EuNiGe$_3$ single crystalline sample is
found to order antiferromagnetically at 13.2 K as revealed from the magnetic
susceptibility, heat capacity and electrical resistivity data. The low
temperature magnetization M(H) is distinctly different for field parallel to
${ab}$-plane and $c$-axis; the ${ab}$-plane magnetization varies nearly
linearly with field before the occurrence of an induced ferromagnetic phase
(spin-flip) at 6.2 Tesla; on the other hand M(H) along the $c$-axis is
accompanied by two metamagnetic transitions followed by a spin-flip at 4.1 T. A
model including anisotropic exchange and dipole-dipole interactions reproduces
the main features of magnetization plots but falls short of full
representation. (H,T) phase diagrams have been constructed for the field
applied along the principal directions. From the $^{151}$Eu M\"{o}ssbauer
spectra, we determine that the 13.2 K transition leads to an incommensurate
antiferromagnetic intermediate phase followed by a transition near 10.5 K to a
commensurate antiferromagnetic configuration.


title:
Anisotropic magnetic properties and giant magnetocaloric effect of PrSi
  single crystal

abstract:
  Single crystal of PrSi was grown by Czochralski method in a tetra-arc
furnace. Powder x-ray diffraction of the as grown crystal revealed that PrSi
crystallizes in FeB$-$type structure with space group $Pnma$ (no. 62). PrSi
undergoes a ferromagnetic transition at 52 K with [010] direction as the easy
axis of magnetization. Heat capacity data confirm the bulk nature of the
transition at 52 K and exhibit a huge anomaly at the transition. A sharp rise
in the low temperature heat capacity has been observed (below 5 K) which is
attributed to the $^{141}$Pr nuclear Schottky heat capacity arising from the
hyperfine field of the Pr moment. The estimated Pr magnetic moment 2.88
$\mu_{\rm B}$/Pr from the hyperfine splitting is in agreement with the
saturation magnetization value obtained from the magnetization data measured at
2 K. From the crystal electric field (CEF) analysis of the magnetic
susceptibility, magnetization and the heat capacity data it is found that the
degenerate $J = 4$ Hund's rule derived state of Pr$^{3+}$-ion splits into nine
singlets with an overall splitting of 284 K, the first excited singlet state
separated by just 9 K from the ground state. The magnetic ordering in PrGe
appears to be due to the exchange generated admixture of low lying crystal
field levels. Magnetocaloric effect (MCE) has been investigated from
magnetization data along all the three principal crystallographic directions.
Large magnetic entropy change, $-\Delta S_M = $22.2 J/kg K, and the relative
cooling power, RCP = $460$ J/kg, characteristic of giant magneto caloric effect
are achieved near the transition temperature ($T_{\rm C}$ = 52 K) for $H =$~70
kOe along $[010]$. Furthermore, the PrSi single crystal exhibits a giant MCE
anisotropy.


title: Adapted Basis for Non-Local Reconstruction of Missing Spectrum

abstract:
  The object of this work is to design an adequate regularization for the
problem of recovering missing Fourier coefficients, particularly in some non
standard situations were low frequency coefficients are lost. In the framework
of non-local regularization, we propose a technique to build an original
patchwise similarity measure that is adapted to the missing spectrum. Then, a
simple Non-Local quadratic energy is minimized. By construction, the similarity
criterion is invariant under the corruption process so that the distance
between two patches of the corrupted image is almost exactly equal to the one
computed on the clean image. We illustrate our method with experiments which
show its efficiency, both in terms of speed and quality of the results, with
respect to other common approaches. We show that the method is practical on
synthetic examples which are built upon models of inverse scattering problems,
synthetic aperture mirrors for spatial imaging or also medical imaging.


title:
Interlayer coupling enhancement in graphene/hexagonal boron nitride
  heterostructures by intercalated defects and vacancies

abstract:
  Among two-dimensional atomic crystals, hexagonal boron nitride (hBN) is one
of the most remarkable materials to fabricate heterostructures revealing
unusual properties. We perform first-principles calculations to determine
whether intercalated metal atoms and vacancies can mediate interfacial coupling
and influence the structural and electronic properties of the graphene/hBN
heterostructure. Metal impurity atoms (Li, K, Cr, Mn, Co, and Cu) as extrinsic
defects between the graphene and hBN sheets produce $n$-doped graphene. We also
consider intrinsic vacancy defects and find that a boron monovacancy in hBN act
as a magnetic dopant for graphene whereas a nitrogen monovacancy in hBN serves
as a nonmagnetic dopant for graphene. In contrast, smallest triangular vacancy
defects in hBN are unlikely to result in significant changes in the electronic
transport of graphene. Our findings reveal that the hBN layer with some
vacancies or metal impurities enhance the interlayer coupling in the
graphene/hBN heterostructure with respect to charge doping and electron
scattering.


title: L^2-Cohomology and complete Hamiltonian manifolds

abstract:
  A classical theorem of Frankel for compact K\"ahler manifolds states that a
K\"ahler S^1-action is Hamiltonian if and only if it has fixed points. We prove
a metatheorem which says that when Hodge theory holds on non-compact manifolds,
then Frankel's theorem still holds. Finally, we present several concrete
situations in which the assumptions of the metatheorem hold.


title: Dual-to-kernel learning with ideals

abstract:
  In this paper, we propose a theory which unifies kernel learning and symbolic
algebraic methods. We show that both worlds are inherently dual to each other,
and we use this duality to combine the structure-awareness of algebraic methods
with the efficiency and generality of kernels. The main idea lies in relating
polynomial rings to feature space, and ideals to manifolds, then exploiting
this generative-discriminative duality on kernel matrices. We illustrate this
by proposing two algorithms, IPCA and AVICA, for simultaneous manifold and
feature learning, and test their accuracy on synthetic and real world data.

categories: stat.ML cs.LG math.AC math.AG math.ST stat.TH


title: Ionized gas rotation curves in nearby dwarf galaxies

abstract:
  We present the results of study of the ionized gas velocity fields in 28
nearby (systemic velocity below 1000 km/s) dwarf galaxies. The observations
were made at the 6-m BTA telescope of the SAO RAS with the scanning Fabry-Perot
interferometer in the H-alpha emission line. We were able to measure regular
circular rotation parameters in 25 galaxies. As a rule, rotation velocities
measured in HII are in a good agreement with the data on the HI kinematics at
the same radii. Three galaxies reveal position angles of the kinematic axis in
the HII velocity fields that strongly (tens of degrees) differ from the
measurements in neutral hydrogen at large distances from the center or from the
orientation of the major axis of optical isophotes. The planes of the gaseous
and stellar disks in these galaxies most likely do not coincide. Namely, in DDO
99 the gaseous disk is warped beyond the optical radius, and in UGC 3672 and
UGC 8508 the inclination of orbits of gas clouds varies in the inner regions of
galaxies. It is possible that the entire ionized gas in UGC 8508 rotates in the
plane polar to the stellar disk.


title: String theory and primordial cosmology

abstract:
  String cosmology aims at providing a reliable description of the very early
Universe in the regime where standard-model physics is no longer appropriate,
and where we can safely apply the basic ingredients of superstring models such
as dilatonic and axionic forces, duality symmetries, winding modes, limiting
sizes and curvatures, higher-dimensional interactions among elementary extended
object. The sought target is that of resolving (or at least alleviating) the
big problems of standard and inflationary cosmology like the spacetime
singularity, the physics of the trans-Planckian regime, the initial condition
for inflation, and so on.


title: Sums of Squares Bijective Parameter Representation

abstract:
  We give a bijective parameter representation for a sum of squares of numbers
being equal to another sum of squares of numbers.


title:
On an equivalence of the topology of algebraic cone metric spaces and
  metric spaces

abstract:
  In this paper, we prove that the topology induced by algebraic cone metric
coincides with the topology induced by the metric obtained via a nonlinear
scalarization function, i.e. any algebraic cone metric space is metrizable.
Furthermore, the notion of algebraic cone normed space is introduced and also
normability of the topology of this space is proved.


title: The Combinatorics of Tandem Duplication

abstract:
  Tandem duplication is an evolutionary process whereby a segment of DNA is
replicated and proximally inserted. The different configurations that can arise
from this process give rise to some interesting combinatorial questions.
Firstly, we introduce an algebraic formalism to represent this process as a
word producing automaton. The number of words arising from n tandem
duplications can then be recursively derived. Secondly, each single word
accounts for multiple evolutions. With the aid of a bi-coloured 2d- tree, a
Hasse diagram corresponding to a partially ordered set is constructed, from
which we can count the number of evolutions corresponding to a given word.
Thirdly, we implement some subtree prune and graft operations on this structure
to show that the total number of possible evolutions arising from n tandem
duplications is $\prod_{k=1}^n(4^k - (2k + 1))$. The space of structures
arising from tandem duplication thus grows at a super-exponential rate with
leading order term $\mathcal{O}(4^{\frac{1}{2}n^2})$.


title: Wind Mass Loss Estimates in QSOs

abstract:
  We derive here a relatively simple expression for the total wind mass loss
rates in QSOs within the accretion disk wind scenario. We show that the simple
expression derived here for QSO disk wind mass loss rate is in very good
agreement with the more "exact" values obtained through significantly more
complex and detailed numerically intensive 2.5D time-dependent simulations.
Additionally we show that for typical QSO parameters, the disk itself will be
emitting mostly in the UV/Optical spectrum, in turn implying that the X-ray
emission from QSOs likely is produced through some physical mechanism acting at
radii smaller than the inner disk radius (for a standard accretion disk, half
of the initially gravitational potential energy of the accreting disk mass is
emitted directly by the disk, while the other half "falls" closer towards the
black hole than the inner disk radius). We also show that for typical QSO
parameters, the disk itself is dominated by continuum radiation pressure
(rather than thermal pressure), resulting in a "flat disk" (except for the
innermost disk regions).


title: Properties of gravity near the Schwarzschild radius

abstract:
  The radius of the observable region of the Universe is of the order of its
Schwarzschild radius. Due to the spherical symmetry, this allows to check the
properties of the gravitational force in the vicinity of the Schwarzschild
radius by comparing the theoretical and observed Hubble diagram at high
redshifts. This can be done in a simple model that fellows from
projective-invariant equations of gravitation.This paper shows that the Hubble
diagram up to $z=8$ testifies in favor of the specific properties of gravity
near and inside of the Schwarzschild radius.


title: Few-body aspects of the near threshold pseudoscalar meson production

abstract:
  During last decade large samples of data have been collected on the
production of the ground-state pseudoscalar mesons in collisions of proton or
deuteron beam with hydrogen or deuterium target. These measurements have been
performed in the vicinity of the kinematical threshold for meson production
where only a few partial waves in both initial and final state are expected to
contribute to the production process. This simplifies significantly the
interpretation of the data, yet still appears to be challenging due to the
three or four particle final state systems with a complex hadronic potential.
We review experiments and phenomenology of the near threshold production of the
ground-state mesons in the few-body final states as for example: nucleus-meson
and nucleon-nucleon-meson, and report on the status of the search of the
mesic-nuclei (a meson-nucleus bound states). Experimental advantages of
measurements close to the kinematical threshold are discussed, and general
features of the production mechanism of the eta and eta prime mesons in the
nucleon-nucleon collisions are presented emphasising results of measurements of
spin and izospin dependence of the production cross sections.


title:
Markov Blanket Ranking using Kernel-based Conditional Dependence
  Measures

abstract:
  Developing feature selection algorithms that move beyond a pure correlational
to a more causal analysis of observational data is an important problem in the
sciences. Several algorithms attempt to do so by discovering the Markov blanket
of a target, but they all contain a forward selection step which variables must
pass in order to be included in the conditioning set. As a result, these
algorithms may not consider all possible conditional multivariate combinations.
We improve on this limitation by proposing a backward elimination method that
uses a kernel-based conditional dependence measure to identify the Markov
blanket in a fully multivariate fashion. The algorithm is easy to implement and
compares favorably to other methods on synthetic and real datasets.


title:
Microscopic and Macroscopic Entropy of Extremal Black Holes in String
  Theory

abstract:
  This is a short review summarizing the current status of the comparison
between microscopic and macroscopic entropy of extremal BPS black holes in
string theory.


title: A partitioned scheme for fluid-composite structure interaction problems

abstract:
  We present a loosely-coupled partitioned scheme for a benchmark problem in
fluid-composite structure interaction. The benchmark problem proposed here
consists of an incompressible, viscous fluid interacting with a composite
structure that consists of two layers: a thin elastic layer which is in contact
with the fluid, and a thick elastic layer which sits on top of the thin layer.
The motivation comes from fluid-structure interaction (FSI) in hemodyam- ics.
The equations of linear elasticity are used to model the thick structural
layer, while the Koiter member/shell equations are used to model the thin
structural layer which serves as fluid-structure interface with mass. An effi-
cient, modular, operator-splitting scheme is proposed to simulate solutions to
the coupled, nonlinear FSI problem. The operator splitting scheme sepa- rates
the elastodynamics structure problem, from a fluid problem in which the thin
structure inertia is included as a Robin-type boundary condition to achieve
unconditional stability, without requiring any sub-iterations within
time-steps. An energy estimate associated with unconditional stability is
derived for the fully nonlinear FSI problem defined on moving domains. Two
instructive numerical examples are presented to test the performance of the
scheme, where it is shown numerically, that the scheme is at least first-order
accurate in time. The second example reveals a new phenomenon in FSI problems:
the presence of a thin fluid-structure interface with mass regularizes
solutions to the full FSI problem.


title: Confined quantum Zeno dynamics of a watched atomic arrow

abstract:
  In a quantum world, a watched arrow never moves. This is the Quantum Zeno
Effect (QZE). Repeatedly asking a quantum system "are you still in your initial
state?" blocks its coherent evolution through measurement back-action. Quantum
Zeno Dynamics (QZD) leaves more freedom to the system. Instead of pinning it to
a single state, it sets a border in its evolution space. Repeatedly asking the
system "did you cross the border?" makes it impenetrable. Since the border can
be designed at will by choosing the measured observable, QZD allows one to
tailor the system's evolution space. Recent proposals, particularly in the
Cavity Quantum Electrodynamics (CQED) context, highlight the interest of QZD
for quantum state engineering tasks, which are the key to quantumenabled
technologies and quantum information processing. We report the observation of
QZD in the 51-dimension Hilbert space of a large angular momentum J = 25.
Continuous selective interrogation limits the evolution of this angular
momentum to an adjustable multi-dimensional subspace. This confined dynamics
leads to the production of non-classical "Schr\"odinger cat" states, quantum
superpositions of angular momentums pointing in different directions. These
states are promising for sensitive metrology of electric and magnetic fields.
This QZD approach could be generalized to other systems, opening novel
perspectives for quantum information processing.


title:
Two-colour QCD at non-zero temperature in the presence of a strong
  magnetic field

abstract:
  In this talk we report on our study of two-colour lattice QCD with N_f=4
staggered fermion degrees of freedom with equal electric charge q in a
homogeneous magnetic field B at non-zero temperature T. We find indications for
a non-monotonic behaviour of the critical temperature as a function of the
magnetic field strength and, as a consequence, for the occurence of `inverse
magnetic catalysis' within the transition region for magnetic fields in the
range 0 < qB < 0.7 GeV^2.


title:
Pointwise Bounds and Blow-up for Systems of Semilinear Elliptic
  Inequalities at an Isolated Singularity via Nonlinear Potential Estimates

abstract:
  We study the behavior near the origin of $C^2$ positive solutions $u(x)$ and
$v(x)$ of the system
  $0\leq -\Delta u\leq f(v)$
  $0\leq -\Delta v\leq g(u)$ in $B_1(0)\backslash\{0\}$ where
$f,g:(0,\infty)\to (0,\infty)$ are continuous functions. We provide optimal
conditions on $f$ and $g$ at $\infty$ such that solutions of this system
satisfy pointwise bounds near the origin. In dimension $n=2$ we show that this
property holds if $\log^+ f$ or $\log^+g$ grow at most linearly at infinity. In
dimension $n\geq 3$ and under the assumption $f(t)=O(t^\lambda)$,
$g(t)=O(t^\sigma)$ as $t\to \infty$, ($\lambda, \sigma\geq 0$), we obtain a new
critical curve that optimally describes the existence of such pointwise bounds.
Our approach relies in part on sharp estimates of nonlinear potentials which
appear naturally in this context.


title: Relaxation of the single-slip condition in strain-gradient plasticity

abstract:
  We consider the variational formulation of both geometrically linear and
geometrically nonlinear elasto-plasticity subject to a class of hard
single-slip conditions. Such side conditions typically render the associated
boundary-value problems non-convex. We show that, for a large class of
non-smooth plastic distortions, a given single-slip condition (specification of
Burgers vectors) can be relaxed by introducing a microstructure through a
two-stage process of mollification and lamination. The relaxed model can be
thought of as an aid to simulating macroscopic plastic behaviour without the
need to resolve arbitrarily fine spatial scales.


title: Non-renormalizability of the classical statistical approximation

abstract:
  In this paper, we discuss questions related to the renormalizability of the
classical statistical approximation, an approximation scheme that has been used
recently in several studies of out-of-equilibrium problems in Quantum Field
Theory. Although the ultraviolet power counting in this approximation scheme is
identical to that of the unapproximated quantum field theory, this
approximation is not renormalizable. The leading cause of this
non-renormalizability is the breakdown of Weinberg's theorem in this
approximation. We also discuss some practical implications of this negative
result for simulations that employ this approximation scheme, and we speculate
about a possible modification of the classical statistical approximation in
order to systematically subtract the leading residual divergences.


title: A Conceptual Framework for ERP Evaluation in Universities of Pakistan

abstract:
  The higher education has been greatly impacted by worldwide trends. In a
result, the universities throughout the world are focusing to enhance
performance and efficiency in their workings. Therefore, the higher education
has moved their systems to Enterprise Resource Planning (ERP) systems to cope
with the needs of changing environment. However, the literature review
indicates that there is void on the evaluation of success or failure of ERP
systems in higher education Institutes in Pakistan. In overall, ERP systems
implementation in higher education of Pakistan has not been given appropriate
research focus. Thus, in this paper the authors have attempted to develop a
conceptual framework for ERP evaluation in Universities of Pakistan. This seeks
to expand the knowledge on ERP in higher educational institutes of Pakistan and
focuses on understanding the ERP related critical success factors.


title: The Supernova-ISM/Star formation Interplay

abstract:
  Supernovae are the most energetic stellar events and influence the
interstellar medium by their gasdynamics and energetics. By this, both also
affect the star formation positively and negatively. In this paper, we review
the complexity of investigations aiming at understanding the interchange
between supernova explosions with the star-forming molecular clouds. Commencing
from analytical studies the paper advances to numerical models of supernova
feedback from superbubble scales to galaxy structure. We also discuss
parametrizations of star-formation and supernova-energy transfer efficiencies.
Since evolutionary models from the interstellar medium to galaxies are numerous
and are applying multiple recipes of these parameters, only a representative
selection of studies can be discussed here.


title: Quintessence Cosmology with an Effective $\Lambda$-Term in Lyra Manifold

abstract:
  In this paper, we study quintessence cosmology with an effective
$\Lambda$-term in Lyra manifold. We consider three different models by choosing
variable $\Lambda$ depend on time, the Hubble parameter and the energy density
of dark matter and dark energy. Dark energy assumed as quintessence which
interacts with the dark matter. By using numerical analysis we investigate
behavior of cosmological parameters in three different models and compare our
results with observational data. Statefinder diagnostic is also performed for
all models.


title: Randomized Nonlinear Component Analysis

abstract:
  Classical methods such as Principal Component Analysis (PCA) and Canonical
Correlation Analysis (CCA) are ubiquitous in statistics. However, these
techniques are only able to reveal linear relationships in data. Although
nonlinear variants of PCA and CCA have been proposed, these are computationally
prohibitive in the large scale.
  In a separate strand of recent research, randomized methods have been
proposed to construct features that help reveal nonlinear patterns in data. For
basic tasks such as regression or classification, random features exhibit
little or no loss in performance, while achieving drastic savings in
computational requirements.
  In this paper we leverage randomness to design scalable new variants of
nonlinear PCA and CCA; our ideas extend to key multivariate analysis tools such
as spectral clustering or LDA. We demonstrate our algorithms through
experiments on real-world data, on which we compare against the
state-of-the-art. A simple R implementation of the presented algorithms is
provided.


title: Arithmetic of positive characteristic L-series values in Tate algebras

abstract:
  The second author has recently introduced a new class of L-series in the
arithmetic theory of function fields over finite fields. We show that the value
at one of these L-series encode arithmetic informations of certain Drinfeld
modules defined over Tate algebras. This enables us to generalize Anderson's
log-algebraicity Theorem and Taelman's Herbrand-Ribet Theorem.


title:
Reliable Communication in a Dynamic Network in the Presence of Byzantine
  Faults

abstract:
  We consider the following problem: two nodes want to reliably communicate in
a dynamic multihop network where some nodes have been compromised, and may have
a totally arbitrary and unpredictable behavior. These nodes are called
Byzantine. We consider the two cases where cryptography is available and not
available. We prove the necessary and sufficient condition (that is, the
weakest possible condition) to ensure reliable communication in this context.
Our proof is constructive, as we provide Byzantine-resilient algorithms for
reliable communication that are optimal with respect to our impossibility
results. In a second part, we investigate the impact of our conditions in three
case studies: participants interacting in a conference, robots moving on a grid
and agents in the subway. Our simulations indicate a clear benefit of using our
algorithms for reliable communication in those contexts.


title: Band gap tunning in BN-doped graphene systems with high carrier mobility

abstract:
  Using density functional theory, we present a comparative study of the
electronic properties of BN-doped graphene monolayer, bilayer, trilayer, and
multilayer systems. In addition, we address a superlattice of pristine and
BN-doped graphene. Five doping concentrations between 12.5% and 75% are
considered, for which we obtain band gaps from 0.02 eV to 2.43 eV. We show that
the effective mass varies between 0.007 and 0.209 free electron masses,
resembling a high mobility of the charge carriers.


title: Rotational State Analysis of AlH+ by Two-Photon Dissociation

abstract:
  We perform ab-initio calculations needed to predict the cross-section of an
experimentally accessible (1+1') resonance-enhanced multiphoton dissociation
(REMPD) pathway in AlH+. Experimenting on AlH+ ions held in a radiofrequency
Paul trap, we confirm dissociation via this channel with analysis performed
using time-of-flight mass spectrometry. We demonstrate the use of REMPD for
rotational state analysis, and we measure the rotational distribution of
trapped AlH+ to be consistent with the expected thermal distribution. AlH+ is a
particularly interesting species for ion trap work because of its electronic
level structure, which makes it amenable to proposals for rotational optical
pumping, direct Doppler cooling, and single-molecule fluorescence detection.
Potential applications of trapped AlH+ include searches for time-varying
constants, quantum information processing, and ultracold chemistry studies.


title:
Free and properly discontinuous actions of groups on homotopy
  $2n$-spheres

abstract:
  Let $G$ be a group acting freely, properly discontinuously and cellularly on
a finite dimensional $C$W-complex $\Sigma(2n)$ which has the homotopy type of
the $2n$- sphere $\mathbb{S}^{2n}$. Then, this action induces an action of the
group $G$ on the top cohomology of $\Sigma(2n)$. For the family of virtually
cyclic groups, we classify all groups which act on $\Sigma(2n)$, the homotopy
type of all possible orbit spaces and all actions on the top cohomology as
well. \par Under the hypothesis that $\mbox{dim}\,\Sigma(2n)\leq 2n+1$, we
study the groups with the virtual cohomological dimension
$\mbox{vcd}\,G<\infty$ which act as above on $\Sigma(2n)$. It turns out that
they consist of free groups and certain semi-direct products $F\rtimes
\mathbb{Z}_2$ with $F$ a free group. For those groups $G$ and a given action of
$G$ on $\mbox{Aut}(\mathbb{Z})$, we present an algebraic criterion equivalent
to the realizability of an action $G$ on $\Sigma(2n)$ which induces the given
action on its top cohomology. Then, we obtain a classification of those groups
together with actions on the top cohomology of $\Sigma(2n)$.


title:
Automated Classification of Periodic Variable Stars detected by the
  Wide-field Infrared Survey Explorer

abstract:
  We describe a methodology to classify periodic variable stars identified
using photometric time-series measurements constructed from the Wide-field
Infrared Survey Explorer (WISE) full-mission single-exposure Source Databases.
This will assist in the future construction of a WISE Variable Source Database
that assigns variables to specific science classes as constrained by the WISE
observing cadence with statistically meaningful classification probabilities.
We have analyzed the WISE light curves of 8273 variable stars identified in
previous optical variability surveys (MACHO, GCVS, and ASAS) and show that
Fourier decomposition techniques can be extended into the mid-IR to assist with
their classification. Combined with other periodic light-curve features, this
sample is then used to train a machine-learned classifier based on the random
forest (RF) method. Consistent with previous classification studies of variable
stars in general, the RF machine-learned classifier is superior to other
methods in terms of accuracy, robustness against outliers, and relative
immunity to features that carry little or redundant class information. For the
three most common classes identified by WISE: Algols, RR Lyrae, and W Ursae
Majoris type variables, we obtain classification efficiencies of 80.7%, 82.7%,
and 84.5% respectively using cross-validation analyses, with 95% confidence
intervals of approximately +/-2%. These accuracies are achieved at purity (or
reliability) levels of 88.5%, 96.2%, and 87.8% respectively, similar to that
achieved in previous automated classification studies of periodic variable
stars.


title:
Kantian fractionalization predicts the conflict propensity of the
  international system

abstract:
  The study of complex social and political phenomena with the perspective and
methods of network science has proven fruitful in a variety of areas, including
applications in political science and more narrowly the field of international
relations. We propose a new line of research in the study of international
conflict by showing that the multiplex fractionalization of the international
system (which we label Kantian fractionalization) is a powerful predictor of
the propensity for violent interstate conflict, a key indicator of the system's
stability. In so doing, we also demonstrate the first use of multislice
modularity for community detection in a multiplex network application. Even
after controlling for established system-level conflict indicators, we find
that Kantian fractionalization contributes more to model fit for violent
interstate conflict than previously established measures. Moreover, evaluating
the influence of each of the constituent networks shows that joint democracy
plays little, if any, role in predicting system stability, thus challenging a
major empirical finding of the international relations literature. Lastly, a
series of Granger causal tests shows that the temporal variability of Kantian
fractionalization is consistent with a causal relationship with the prevalence
of conflict in the international system. This causal relationship has
real-world policy implications as changes in Kantian fractionalization could
serve as an early warning sign of international instability.


title: A note on Lax pairs of the Sawada-Kotera equation

abstract:
  We prove that the new Lax pair of the Sawada-Kotera equation, discovered
recently by Hickman, Hereman, Larue, and Goktas, and the well-known old Lax
pair of this equation, considered in the form of zero-curvature
representations, are gauge equivalent to each other if and only if the spectral
parameter is nonzero, while for zero spectral parameter a non-gauge
transformation is required.


title:
Hubble Space Telescope Far Ultraviolet Spectroscopy of the Recurrent
  Nova T Pyxidis

abstract:
  With six recorded nova outbursts, the prototypical recurrent nova T Pyxidis
is the ideal cataclysmic variable system to assess the net change of the white
dwarf mass within a nova cycle. Recent estimates of the mass ejected in the
2011 outburst ranged from a few 1.E-5 sollar mass to 3.3E-4 sollar mass, and
assuming a mass accretion rate of 1.E-8 to 1.E-7 Sollar mass/yr for 44yrs, it
has been concluded that the white dwaf in T Pyx is actually losing mass. Using
NLTE disk modeling spectra to fit our recently obtained Hubble Space Telescope
(HST) COS and STIS spectra, we find a mass accretion rate of up to two orders
of magnitude larger than previously estimated. Our larger mass accretion rate
is due mainly to the newly derived distance of T Pyx (4.8kpc; Sokoloski et al.
2013, larger than the previous 3.5kpc estimate), our derived reddening of
E(B-V)=0.35 (based on combined IUE and GALEX spectra) and NLTE disk modeling
(compared to black body and raw flux estimates in earlier works). We find that
for most values of the reddening (0.25 < E(B-V) < 0.50) and white dwaf mass
(0.70 to 1.35 Sollar mass) the accreted mass is larger than the ejected mass.
Only for a low reddening (0.25 and smaller) combined with a large white dwaf
mass (0.9 sollar mass and larger) is the ejected mass larger than the accreted
one. However, the best spectral fitting results are obtained for a larger value
of the reddening.


title: Strong Majorization Entropic Uncertainty Relations

abstract:
  We analyze entropic uncertainty relations in a finite dimensional Hilbert
space and derive several strong bounds for the sum of two entropies obtained in
projective measurements with respect to any two orthogonal bases. We improve
the recent bounds by Coles and Piani, which are known to be stronger than the
well known result of Maassen and Uffink. Furthermore, we find a novel bound
based on majorization techniques, which also happens to be stronger than the
recent results involving largest singular values of submatrices of the unitary
matrix connecting both bases. The first set of new bounds give better results
for unitary matrices close to the Fourier matrix, while the second one provides
a significant improvement in the opposite sectors. Some results derived admit
generalization to arbitrary mixed states, so that corresponding bounds are
increased by the von Neumann entropy of the measured state. The majorization
approach is finally extended to the case of several measurements.


title: Dynamical Properties of a Two-gene Network with Hysteresis

abstract:
  A mathematical model for a two-gene regulatory network is derived and several
of their properties analyzed. Due to the presence of mixed continuous/discrete
dynamics and hysteresis, we employ a hybrid systems model to capture the
dynamics of the system. The proposed model incorporates binary hysteresis with
different thresholds capturing the interaction between the genes. We analyze
properties of the solutions and asymptotic stability of equilibria in the
system as a function of its parameters. Our analysis reveals the presence of
limit cycles for a certain range of parameters, behavior that is associated
with hysteresis. The set of points defining the limit cycle is characterized
and its asymptotic stability properties are studied. Furthermore, the stability
property of the limit cycle is robust to small perturbations. Numerical
simulations are presented to illustrate the results.


title:
The controversial early brightening in the first half of 20th century: a
  contribution from pyrheliometer measurements in Madrid (Spain)

abstract:
  A long-term decrease in downward surface solar radiation from the 1950s to
the 1980s ("global dimming") followed by a multi-decadal increase up to the
present ("brightening") have been detected in many regions worldwide. In
addition, some researchers have suggested the existence of an "early
brightening" period in the first half of 20th century. However, this latter
phenomenon is an open issue due to the opposite results found in literature and
the scarcity of solar radiation data during this period. This paper contributes
to this relevant discussion analyzing, for the first time in Southern Europe,
the atmospheric column transparency derived from pyrheliometer measurements in
Madrid (Spain) for the period 1911-1928. This time series is one of the three
longest dataset during the first quarter of the 20th century in Europe. The
results showed the great effects of the Katmai eruption (June 1912, Alaska) on
transparency values during 1912-1913 with maximum relative anomalies around 8%.
Outside the period affected by this volcano, the atmospheric transparency
exhibited a stable behavior with a slight negative trend without any
statistical significance on an annual and seasonal basis. Overall, there is no
evidence of a possible early brightening period in direct solar radiation in
Madrid. This phenomenon is currently an open issue and further research is
needed using the few sites with available experimental records during the first
half of the 20th century.


title: Einstein's steady-state theory: an abandoned model of the cosmos

abstract:
  We present a translation and analysis of an unpublished manuscript by Albert
Einstein in which he attempted to construct a 'steady-state' model of the
universe. The manuscript, which appears to have been written in early 1931,
demonstrates that Einstein once explored a cosmic model in which the mean
density of matter in an expanding universe is maintained constant by the
continuous formation of matter from empty space. This model is very different
to previously known Einsteinian models of the cosmos (both static and dynamic)
but anticipates the later steady-state cosmology of Hoyle, Bondi and Gold in
some ways. We find that Einstein's steady-state model contains a fundamental
flaw and suggest that it was abandoned for this reason. We also suggest that he
declined to explore a more sophisticated version because he found such theories
rather contrived. The manuscript is of historical interest because it reveals
that Einstein debated between steady-state and evolving models of the cosmos
decades before a similar debate took place in the cosmological community.


title: Evaluation of one exotic Furdui type series

abstract:
  This is a closed form evaluation of one interesting alternating series whose
value is a combination of three mathematical constants, Pi, log 2, and Zeta
(3).


title: On the Decision Number of Graphs

abstract:
  Let $G$ be a graph. A good function is a function $f:V(G)\rightarrow
\{-1,1\}$, satisfying $f(N(v))\geq 1$, for each $v\in V(G)$, where $
N(v)=\{u\in V(G)\, |\, uv\in E(G) \} $ and $f(S) = \sum_{u\in S} f(u)$ for
every $S \subseteq V(G) $. For every cubic graph $G$ of order $ n, $ we prove
that $ \gamma(G) \leq \frac{5n}{7} $ and show that this inequality is sharp. A
function $f:V(G)\rightarrow \{-1,1\}$ is called a nice function, if
$f(N[v])\le1$, for each $v\in V(G)$, where $ N[v]=\{v\} \cup N(v) $. Define
$\overline{\beta}(G)=max\{f(V(G))\}$, where $f$ is a nice function for $G$. We
show that $\overline\beta(G)\ge -\frac{3n}{7}$ for every cubic graph $G$ of
order $n$, which improves the best known bound $-\frac{n}{2}$.


title:
Property RD and the Classification of Traces on Reduced Group
  $C^*$-algebras of Hyperbolic Groups

abstract:
  In this paper, we show that if $G$ by a non-elementary word hyperbolic group
and $a \in G$ an element, if the conjugacy class of $a$ is infinite, then all
traces $\tau:C^*_{\text{red}}(G) \to \mathbb{C}$ vanish on $a$. We show that
all traces $\theta:C^*_{\text{red}}(G) \to \mathbb{C}$ are linear combinations
of traces $\chi_g:C^*_{\text{red}}(G) \to \mathbb{C}$ given by
\[\chi_{g}=\begin{cases} 1 & g \in C(g) \\ 0 & \text{else}\end{cases}\] where
$C(g)$ is the conjugacy class of $g$. To do this, we introduce a new method to
study traces, using Sobolev norms and property RD.


title:
IsoDOT Detects Differential RNA-isoform Expression/Usage with respect to
  a Categorical or Continuous Covariate with High Sensitivity and Specificity

abstract:
  We have developed a statistical method named IsoDOT to assess differential
isoform expression (DIE) and differential isoform usage (DIU) using RNA-seq
data. Here isoform usage refers to relative isoform expression given the total
expression of the corresponding gene. IsoDOT performs two tasks that cannot be
accomplished by existing methods: to test DIE/DIU with respect to a continuous
covariate, and to test DIE/DIU for one case versus one control. The latter task
is not an uncommon situation in practice, e.g., comparing paternal and maternal
allele of one individual or comparing tumor and normal sample of one cancer
patient. Simulation studies demonstrate the high sensitivity and specificity of
IsoDOT. We apply IsoDOT to study the effects of haloperidol treatment on mouse
transcriptome and identify a group of genes whose isoform usages respond to
haloperidol treatment.


title:
On the Longest Common Pattern Contained in Two or More Random
  Permutations

abstract:
  We provide upper and lower bounds for the expected length $\mathbb
E(L_{n,m})$ of the longest common pattern contained in $m$ random permutations
of length $n$. We also address the tightness of the concentration of $L_{n,m}$
around $\mathbb E(L_{n,m})$.


title:
Phase stability and Nucleation effect upon Iron addition to SmCo5 bulk
  magnets

abstract:
  Change in structure and magnetic properties of SmCo5-xFex permanent magnets
for different values of x ranging from 0 to 2 have been studied. Structural
investigation from X-ray diffraction (XRD) patterns confirms the hexagonal
CaCu5-type structure of the SmCo5-xFex ribbons for 0<x<2. The decrease in
angular position of the diffraction peaks points to the lattice expansion due
to the substitution of Co atoms by larger Fe atoms. Mixture of phases occurs
for x>2 and has been confirmed by both XRD studies and magnetic measurements.
Nucleation effect induced by the additive Fe enhances the coercivity (Hc)up to
27 kOe which is much larger than 4.5 kOe obtained for pure SmCo5.


title:
The Political Economy of FDI flows into Developing Countries: Does the
  depth of International Trade Agreements Matter?

abstract:
  There is considerable debate whether the domestic political institutions
(specifically, the country s level of democracy) of the host developing country
toward foreign investors are effective in establishing the credibility of
commitments are still underway, researchers have also analyzed the effect of
international institutions such as (GATT-WTO) membership and Bilateral
Investment treaties (BIT) in their role of establishing the credibility of
commitment to attract foreign investments. We argue that there are qualitative
differences among various types of trade agreements and full-fledged trade
agreements (FTA-CU) provide credibility to foreign investors and democracy
level in the host country conditions this effect whereas the partial scope
agreements (PSA) are not sufficient in providing credibility of commitments and
not moderated by democracy. This paper analyses the impact of heterogeneous
TAs, and their interaction with domestic institutions, on FDI inflows.
Statistical analyses for 122 developing countries from 1970 to 2005 support
this argument. The method adopted relies on fixed effects estimator which is
robust to control endogeneity on a large panel dataset. The strict erogeneity
of results by using a method suggested by Baier and Bergstrand (2007) and no
feedback effect found in sample. The results state that (1) More the FTA-CU
concluded, larger the amount of FDI inflows are attracted into the developing
countries and PSA are insignificant in determining the FDI inflow; (2) FTA CU
are complementary to democratic regime whereas the conditional effect of PSA
with democracy on levels of FDI inflows is insignificant.


title: Probabilistic Model Validation for Uncertain Nonlinear Systems

abstract:
  This paper presents a probabilistic model validation methodology for
nonlinear systems in time-domain. The proposed formulation is simple,
intuitive, and accounts both deterministic and stochastic nonlinear systems
with parametric and nonparametric uncertainties. Instead of hard invalidation
methods available in the literature, a relaxed notion of validation in
probability is introduced. To guarantee provably correct inference, algorithm
for constructing probabilistically robust validation certificate is given along
with computational complexities. Several examples are worked out to illustrate
its use.


title: Diagonal Differential Operators

abstract:
  We explore differential operators, $T$, that diagonalize on a simple basis,
$\{B_n(x)\}_{n=0}^\infty$, with respect to some sequence of real numbers,
$\{a_n\}_{n=0}^\infty$, and sequence of polynomials, $\{Q_k(x)\}_{k=0}^\infty$,
as in $ T[B_n(x)]:=\left(\sum_{k=0}^\infty Q_k(x) D^k\right)B_n(x)=a_n B_n(x)$
for every $n\in\mathbb{N}_0$. We discover new relationships between the
sequence, $\{Q_k(x)\}_{k=0}^\infty$, and the sequence, $\{a_n\}_{n=0}^\infty$.
We find new relationships between polynomial interpolated eigenvalues and the
sequence, $\{\deg(Q_k(x))\}_{k=0}^\infty$.


title: A paradox from randomization-based causal inference

abstract:
  Under the potential outcomes framework, causal effects are defined as
comparisons between potential outcomes under treatment and control. To infer
causal effects from randomized experiments, Neyman proposed to test the null
hypothesis of zero average causal effect (Neyman's null), and Fisher proposed
to test the null hypothesis of zero individual causal effect (Fisher's null).
Although the subtle difference between Neyman's null and Fisher's null has
caused lots of controversies and confusions for both theoretical and practical
statisticians, a careful comparison between the two approaches has been lacking
in the literature for more than eighty years. We fill in this historical gap by
making a theoretical comparison between them and highlighting an intriguing
paradox that has not been recognized by previous researchers. Logically,
Fisher's null implies Neyman's null. It is therefore surprising that, in actual
completely randomized experiments, rejection of Neyman's null does not imply
rejection of Fisher's null for many realistic situations, including the case
with constant causal effect. Furthermore, we show that this paradox also exists
in other commonly-used experiments, such as stratified experiments,
matched-pair experiments, and factorial experiments. Asymptotic analyses,
numerical examples, and real data examples all support this surprising
phenomenon. Besides its historical and theoretical importance, this paradox
also leads to useful practical implications for modern researchers.


title:
Automorphisms of Niemeier lattices for Miyamoto's
  $\mathbb{Z}_3$-orbifold construction

abstract:
  We classify, up to conjugation, all automorphisms of Niemeier lattices to
which we can apply Miyamoto's orbifold construction. Using this classification,
we prove that the VOAs obtained in [M] and [SS] are all of holomorphic
non-lattice VOAs which we can obtain by applying the $\mathbb{Z}_3$-orbifold
construction to a Niemeier lattice and its automorphism.


title: Strongly Homotopy Lie Algebras from Multisymplectic Geometry

abstract:
  This Master Thesis is devoted to the study of $n$-plectic manifolds and the
Strongly Homotopy Lie algebras, also called $L_{\infty}$-algebras, that can be
associated to them. Since multisymplectic geometry and $L_{\infty}$-algebras
are relevant in Theoretical Physics, and in particular in String Theory, we
introduce the relevant background material in order to make the exposition
accessible to non-experts, perhaps interested physicists. The background
material includes graded and homological algebra theory, fibre bundles, basics
of group actions on manifolds and symplectic geometry. We give an introduction
to $L_{\infty}$-algebras and define $L_{\infty}$-morphisms in an independent
way, not yet related to multisymplectic geometry, giving explicit formulae
relating $L_{\infty}[1]$-algebras and $L_{\infty}$-algebras. We give also an
account of multisymplectic geometry and $n$-plectic manifolds, connecting them
to $L_{\infty}$-algebras. We then introduce, closely following the work
{1304.2051} of Yael Fregier, Christopher L. Rogers and Marco Zambon, the
concept of homotopy moment map. The new results presented here are the
following: we obtain specific conditions under which two $n$-plectic manifolds
with strictly isomorphic Lie-$n$ algebras are symplectomorphic, and we study
the construction of an homotopy moment map for a product manifold, assuming
that the factors are $n$-plectic manifolds equipped with the corresponding
homotopy moment maps.


title:
Absolute measurement of thermal noise in a resonant short-range force
  experiment

abstract:
  Planar, double-torsional oscillators are especially suitable for short-range
macroscopic force search experiments, since they can be operated at the limit
of instrumental thermal noise. As a study of this limit, we report a
measurement of the noise kinetic energy of a polycrystalline tungsten
oscillator in thermal equilibrium at room temperature. The fluctuations of the
oscillator in a high-Q torsional mode with a resonance frequency near 1 kHz are
detected with capacitive transducers coupled to a sensitive differential
amplifier. The electronic processing is calibrated by means of a known
electrostatic force and input from a finite element model. The measured average
kinetic energy is in agreement with the expected value of 1/2 kT.

categories: cond-mat.stat-mech gr-qc hep-ph physics.ins-det


title:
Remarks on AKS Primality Testing Algorithm and A Flaw in the Definition
  of P

abstract:
  We remark that the AKS primality testing algorithm [Annals of Mathematics 160
(2), 2004] needs about 1,000,000,000 G (gigabyte) storage space for a number of
1024 bits. The requirement is very hard to meet. The complexity class P which
contains all decision problems that can be solved by a deterministic Turing
machine using a polynomial amount of computation time, is generally believed to
be ``easy". We point out that the time is estimated only in terms of the amount
of arithmetic operations. It does not comprise the time for reading and writing
data on the tape in a Turing machine. The flaw makes some deterministic
polynomial time algorithms impractical, and humbles the importance of P=NP
question.


title:
A Probabilistic Method for Nonlinear Robustness Analysis of F-16
  Controllers

abstract:
  This paper presents a new framework for controller robustness verification
with respect to F-16 aircraft's closed-loop performance in longitudinal flight.
We compare the state regulation performance of a linear quadratic regulator
(LQR) and a gain-scheduled linear quadratic regulator (gsLQR), applied to
nonlinear open-loop dynamics of F-16, in presence of stochastic initial
condition and parametric uncertainties, as well as actuator disturbance. We
show that, in presence of initial condition uncertainties alone, both LQR and
gsLQR have comparable immediate and asymptotic performances, but the gsLQR
exhibits better transient performance at intermediate times. This remains true
in the presence of additional actuator disturbance. Also, gsLQR is shown to be
more robust than LQR, against parametric uncertainties. The probabilistic
framework proposed here, leverages transfer operator based density computation
in exact arithmetic and introduces optimal transport theoretic performance
validation and verification (V&V) for nonlinear dynamical systems. Numerical
results from our proposed method, are in unison with Monte Carlo simulations.


title: The Low-Spin Black Hole in LMC X-3

abstract:
  Building upon a new dynamical model for the X-ray binary LMC X-3, we measure
the spin of its black hole primary via the continuum-fitting method. We
consider over one thousand thermal-state RXTE X-ray spectra of LMC X-3. Using a
large subset of these spectra, we constrain the spin parameter of the black
hole to be spin = 0.21(+0.18,-0.22), 90% confidence. Our estimate of the
uncertainty in spin takes into account a wide range of systematic errors. We
discuss evidence for a correlation between a black hole's spin and the
complexity of its X-ray spectrum.


title: Multi-scale Modeling for Piezoelectric Composite Materials

abstract:
  In this paper, we focus on multi-scale modeling and simulation of
piezoelectric composite materials. A multi-scale model for piezoelectric
composite materials under the framework of Heterogeneous Multi-scale
Method(HMM) is proposed. For materials with periodic microstructure,
macroscopic model is derived from microscopic model of piezoelectric composite
material by asymptotic expansion. Convergence analysis under the framework of
homogenization theory is carried out. Moreover, error estimate between HMM
solutions and homogenization solutions is derived. A 3-D numerical example of
1-3 type piezoelectric composite materials is employed to verify the error
estimate.


title:
Towards a realistic model of quarks and leptons, leptonic CP violation
  and neutrinoless $\beta\beta$-decay

abstract:
  In order to explain the fermion masses and mixings naturally, we introduce a
specific flavor symmetry and mass suppression pattern that constrain the flavor
structure of the fermion Yukawa couplings. Our model describes why the
hierarchy of neutrino masses is milder than the hierarchy of charged fermion
masses in terms of successive powers of flavon fields. We investigate CP
violation and neutrinoless double beta ($0\nu\beta\beta$) decay, and show how
they can be predicted and constrained in our model by present and upcoming
experimental data. Our model predicts that the atmospheric neutrino mixing
angle $\theta_{23}$ should be within $\sim1^{\circ}$ of $45^\circ$ for the
normal neutrino mass ordering (NO), and between $\sim4^\circ$ and $\sim8^\circ$
degrees away from $45^\circ$ (in either direction) for the inverted neutrino
mass ordering (IO). For both NO and IO, our model predicts that a
$0\nu\beta\beta$ Majorana mass in the limited range $0.035
\text{eV}<|m_{ee}|\lesssim0.15$ eV, which can be tested in current experiments.
Moreover, our model can successfully accommodate flavorless leptogenesis as the
mechanism to generate the baryon asymmetry in the Universe, provided the
neutrino mass ordering is normal, $|m_{ee}|\simeq0.072\pm0.012$ eV, and either
$\theta_{23}\simeq44^{\circ}$ and the Dirac CP-violating phase
$\delta_{CP}\simeq20^{\circ}$ or $60^{\circ}$, or $\theta_{23}\simeq46^{\circ}$
and $\delta_{CP} \simeq205^{\circ}$ or $245^{\circ}$.


title: New narrow N*(1685) resonance: review of observations

abstract:
  The recent Review of Particle Physics [1] includes a new narrow N*(1685)
resonance. Its properties, the narrow width and the strong photoexcitation on
the neutron, are unusual. The paper reviews experimental data which have led to
the evidence for this resonance. Alternative explanations of the phenomenon at
W ~ 1.685 GeV, namely the interference of well-known resonances and the
sub-threshold meson-baryon production, are discussed as well.