title: Powers of the Phantom Ideal

abstract:
  It is proved that if G is a finite group, then the order of G is a proper
upper bound for the phantom number of G. More specifically, if k is a field
whose characteristic divides the order of G, and $\Phi$ is the ideal of phantom
morphisms in the stable category k[G]-$\underline{\rm Mod}$ of modules over the
group algebra k[G], then $\Phi^{n-1} = 0,$ where n is the nilpotency index of
the Jacobson radical J of k[G]. If $R$ is a semiprimary ring, with $J^n =0,$
and $\Phi$ denotes the phantom ideal in the module category R-Mod, then
$\Phi^n$ is the ideal of morphisms that factor through a projective module. If
R is a right coherent ring and every cotorsion left R-module has a coresolution
of length $n$ by pure injective modules, then $\Phi^{n+1}$ is the ideal of
morphisms that factor through a flat module.
  These results are obtained by introducing the mono-epi (ME) exact structure
on the morphisms of an exact category (${\mathcal A}; {\mathcal E}$), used to
prove new versions of Salce's Lemma, the Ghost Lemma of Christensen, and
Wakamatsu's Lemma. Salce's Lemma gives a bijective correspondence between
special precovering ideals and special preenveloping ideals. The exact category
(Arr (${\mathcal A}$); ME) of morphisms allows us to introduce the notion of an
extension $i \star j$ of morphisms and the notion of an extension of ideals in
(${\mathcal A}; {\mathcal E}$). The Ghost Lemma asserts that the class of
special precovering (resp., special preenveloping) ideals is closed under
products and extensions and that the bijective correspondence of Salce's Lemma
replaces multiplication with extension. Wakamatsu's Lemma is the statement that
if a covering ideal is closed under extensions of morphisms, then it is a
special precovering ideal with a syzygy ideal generated by objects.


title:
Moving-Horizon Dynamic Power System State Estimation Using Semidefinite
  Relaxation

abstract:
  Accurate power system state estimation (PSSE) is an essential prerequisite
for reliable operation of power systems. Different from static PSSE, dynamic
PSSE can exploit past measurements based on a dynamical state evolution model,
offering improved accuracy and state predictability. A key challenge is the
nonlinear measurement model, which is often tackled using linearization,
despite divergence and local optimality issues. In this work, a moving-horizon
estimation (MHE) strategy is advocated, where model nonlinearity can be
accurately captured with strong performance guarantees. To mitigate local
optimality, a semidefinite relaxation approach is adopted, which often provides
solutions close to the global optimum. Numerical tests show that the proposed
method can markedly improve upon an extended Kalman filter (EKF)-based
alternative.


title: When asymptotic LOCC offers no advantage over finite LOCC

abstract:
  We consider bipartite LOCC, the class of operations implementable by local
quantum operations and classical communication between two parties.
Surprisingly, there are operations that cannot be implemented with finitely
many messages but can be approximated to arbitrary precision with more and more
messages. This significantly complicates the analysis of what can or cannot be
approximated with LOCC. Towards alleviating this problem, we exhibit two
scenarios in which allowing vanishing error does not help. The first scenario
involves implementation of measurements with projective product measurement
operators. The second scenario is the discrimination of unextendible product
bases on two 3-dimensional systems.


title:
Volume reduction in large-N lattice gauge theories [with adjoint
  fermions]

abstract:
  This work covers volume reduction in quantum field theories on a lattice at
large $N$ (number of colors), as first described by Eguchi and Kawai in 1982.
The volume reduction (or volume independence) means that the theory defined on
an arbitrarily small lattice is equivalent in the large-$N$ limit to the theory
on an infinite lattice with the same bare parameters. We analyze the volume
reduction by means of Monte Carlo simulations using the lattice model on a
single site (or a small fixed number of sites) with Wilson fermions in the
adjoint representation, using $N$ up to 60. Most of the results focus on two
flavours of Dirac fermions and the single fermionic flavour is also discussed
where there is a significant difference of behaviour. We find that the
$(Z_N)^4$ center symmetry, necessary for the realization of volume reduction,
is unbroken in the reduced model for a large range of parameters and, in
particular, that the maximum admissible value of the adjoint fermion mass is
non-zero in the large-$N$ limit. We calculate physical quantities, such as the
plaquette, the static quark potential and the eigenvalues of the Dirac
operator. We analyze the finite-$N$ corrections and consider the practicality
of volume-reduced models in supplementing the large-volume calculations.


title:
Exciton coupling induces vibronic hyperchromism in light-harvesting
  complexes

abstract:
  The recently suggested possibility that weak vibronic transitions can be
excitonically enhanced in light-harvesting complexes is studied in detail. A
vibronic exciton dimer model which includes ground state vibrations is
investigated using multi-configuration time-dependent Hartree method with a
parameter set typical to photosynthetic light-harvesting complexes. Absorption
spectra are discussed in dependence on the Coulomb coupling, the detuning of
site energies, and the number of vibrational mode. Calculations of the
fluorescence spectra show that the spectral densities obtained from the low
temperature fluorescence line narrowing measurements of light-harvesting
systems need to be corrected for the exciton effects. For the J-aggregate
configuration, as in most of the light-harvesting complexes, the true spectral
density has larger amplitude than what is obtained from the measurement.


title:
Measurement of the properties of a Higgs boson in the four-lepton final
  state

abstract:
  The properties of a Higgs boson candidate are measured in the H to ZZ to 4l
decay channel, with l = e, mu, using data from pp collisions corresponding to
an integrated luminosity of 5.1 inverse femtobarns at the center-of-mass energy
of sqrt(s) = 7 TeV and 19.7 inverse femtobarns at sqrt(s) = 8 TeV, recorded
with the CMS detector at the LHC. The new boson is observed as a narrow
resonance with a local significance of 6.8 standard deviations, a measured mass
of 125.6 +- 0.4 (stat) +- 0.2 (syst) GeV, and a total width less than 3.4 GeV
at the 95% confidence level. The production cross section of the new boson
times its branching fraction to four leptons is measured to be 0.93 +0.26 -0.23
(stat) +0.13 -0.09 (syst) times that predicted by the standard model. Its
spin-parity properties are found to be consistent with the expectations for the
standard model Higgs boson. The hypotheses of a pseudoscalar and all tested
spin-one boson hypotheses are excluded at the 99% confidence level or higher.
All tested spin-two boson hypotheses are excluded at the 95% confidence level
or higher.


title:
Classification of Human Ventricular Arrhythmia in High Dimensional
  Representation Spaces

abstract:
  We studied classification of human ECGs labelled as normal sinus rhythm,
ventricular fibrillation and ventricular tachycardia by means of support vector
machines in different representation spaces, using different observation
lengths. ECG waveform segments of duration 0.5-4 s, their Fourier magnitude
spectra, and lower dimensional projections of Fourier magnitude spectra were
used for classification. All considered representations were of much higher
dimension than in published studies. Classification accuracy improved with
segment duration up to 2 s, with 4 s providing little improvement. We found
that it is possible to discriminate between ventricular tachycardia and
ventricular fibrillation by the present approach with much shorter runs of ECG
(2 s, minimum 86% sensitivity per class) than previously imagined. Ensembles of
classifiers acting on 1 s segments taken over 5 s observation windows gave best
results, with sensitivities of detection for all classes exceeding 93%.


title: Generative NeuroEvolution for Deep Learning

abstract:
  An important goal for the machine learning (ML) community is to create
approaches that can learn solutions with human-level capability. One domain
where humans have held a significant advantage is visual processing. A
significant approach to addressing this gap has been machine learning
approaches that are inspired from the natural systems, such as artificial
neural networks (ANNs), evolutionary computation (EC), and generative and
developmental systems (GDS). Research into deep learning has demonstrated that
such architectures can achieve performance competitive with humans on some
visual tasks; however, these systems have been primarily trained through
supervised and unsupervised learning algorithms. Alternatively, research is
showing that evolution may have a significant role in the development of visual
systems. Thus this paper investigates the role neuro-evolution (NE) can take in
deep learning. In particular, the Hypercube-based NeuroEvolution of Augmenting
Topologies is a NE approach that can effectively learn large neural structures
by training an indirect encoding that compresses the ANN weight pattern as a
function of geometry. The results show that HyperNEAT struggles with performing
image classification by itself, but can be effective in training a feature
extractor that other ML approaches can learn from. Thus NeuroEvolution combined
with other ML methods provides an intriguing area of research that can
replicate the processes in nature.


title: A hyperelliptic solution class for the hyperbolic Ernst equation

abstract:
  A new hyperelliptic solution class for the hyperbolic Ernst equation is
obtained by transforming the regarding solution of the elliptic Ernst equation.
Furthermore, a nontrivial way for obtaining general polarized colliding wave
solutions from this hyperelliptic family of solutions is presented. The
explicit form of the solutions for a Riemann surface of genus n=1 is given. In
addition, an explicit example in terms of a Khan-Penrose seed is provided,
emphasizing the importance of the presented procedure for generating general
polarized colliding plane-wave space times from space-times with a collinear
polarization of the colliding waves.


title:
Charged-current quasielastic neutrino cross sections on $^{12}$C with
  realistic spectral and scaling functions

abstract:
  Charge-current quasielastic (CCQE) (anti)neutrino scattering cross sections
on a $^{12}$C target are analyzed using a spectral function $S(p,{\cal E})$
that gives a scaling function in accordance with the ($e,e'$) scattering data.
The spectral function accounts for the nucleon-nucleon (NN) correlations, it
has a realistic energy dependence and natural orbitals (NO's) from the Jastrow
correlation method are used in its construction. In all calculations the
standard value of the axial mass $M_A= 1.032$ GeV/c$^2$ is used. The results
are compared with those when NN correlations are not included, as in the
Relativistic Fermi Gas (RFG) model, or when harmonic-oscillator (HO)
single-particle wave functions are used instead of NO's. The role of the
final-state interactions (FSI) on the theoretical spectral and scaling
functions, as well as on the cross sections is accounted for. A comparison of
the results for the cases with and without FSI, as well as to results from the
phenomenological scaling function obtained from the superscaling analysis
(SuSA) is carried out. Our calculations based on the impulse approximation (IA)
underpredict the MiniBooNE data, but agree with the data from the NOMAD
experiment. The possible missing ingredients in the considered theoretical
models are discussed.


title:
Planetary Candidates Observed by Kepler IV: Planet Sample From Q1-Q8 (22
  Months)

abstract:
  We provide updates to the Kepler planet candidate sample based upon nearly
two years of high-precision photometry (i.e., Q1-Q8). From an initial list of
nearly 13,400 Threshold Crossing Events (TCEs), 480 new host stars are
identified from their flux time series as consistent with hosting transiting
planets. Potential transit signals are subjected to further analysis using the
pixel-level data, which allows background eclipsing binaries to be identified
through small image position shifts during transit. We also re-evaluate Kepler
Objects of Interest (KOI) 1-1609, which were identified early in the mission,
using substantially more data to test for background false positives and to
find additional multiple systems. Combining the new and previous KOI samples,
we provide updated parameters for 2,738 Kepler planet candidates distributed
across 2,017 host stars. From the combined Kepler planet candidates, 472 are
new from the Q1-Q8 data examined in this study. The new Kepler planet
candidates represent ~40% of the sample with Rp~1 Rearth and represent ~40% of
the low equilibrium temperature (Teq<300 K) sample. We review the known biases
in the current sample of Kepler planet candidates relevant to evaluating planet
population statistics with the current Kepler planet candidate sample.


title: Living Liquid Crystals

abstract:
  Collective motion of self-propelled organisms or synthetic particles often
termed active fluid has attracted enormous attention in broad scientific
community because of it fundamentally non-equilibrium nature. Energy input and
interactions among the moving units and the medium lead to complex dynamics.
Here we introduce a new class of active matter, living liquid crystals (LLCs)
that combine living swimming bacteria with a lyotropic liquid crystal. The
physical properties of LLCs can be controlled by the amount of oxygen available
to bacteria, by concentration of ingredients, or by temperature. Our studies
reveal a wealth of new intriguing dynamic phenomena, caused by the coupling
between the activity-triggered flow and long-range orientational order of the
medium. Among these are (a) non-linear trajectories of bacterial motion guided
by non-uniform director, (b) local melting of the liquid crystal caused by the
bacteria-produced shear flows, (c) activity-triggered transition from a
non-flowing uniform state into a flowing one-dimensional periodic pattern and
its evolution into a turbulent array of topological defects, (d)
birefringence-enabled visualization of microflow generated by the
nanometers-thick bacterial flagella. Unlike their isotropic counterpart, the
LLCs show collective dynamic effects at very low volume fraction of bacteria,
on the order of 0.2%. Our work suggests an unorthodox design concept to control
and manipulate the dynamic behavior of soft active matter and opens the door
for potential biosensing and biomedical applications.

categories: cond-mat.soft cond-mat.mes-hall physics.bio-ph physics.flu-dyn


title: Pair-Instability Supernovae in the Local Universe

abstract:
  The discovery of 150 - 300 M$_{\odot}$ stars in the Local Group and
pair-instability supernova candidates at low redshifts has excited interest in
this exotic explosion mechanism. Realistic light curves for pair-instability
supernovae at near-solar metallicities are key to identifying and properly
interpreting these events as more are found. We have modeled pair-instability
supernovae of 150 - 500 M$_{\odot}$ Z $\sim$ 0.1 - 0.4 Z$_{\odot}$ stars. These
stars lose up to 80% of their mass to strong line-driven winds and explode as
bare He cores. We find that their light curves and spectra are quite different
from those of Population III pair-instability explosions, which therefore
cannot be used as templates for low-redshift events. Although non-zero
metallicity pair-instability supernovae are generally dimmer than their
Population III counterparts, in some cases they will be bright enough to be
detected at the earliest epochs at which they can occur, the formation of the
first galaxies at $z \sim$ 10 - 15. Others can masquerade as dim, short
duration supernovae that are only visible in the local universe and that under
the right conditions could be hidden in a wide variety of supernova classes. We
also report for the first time that some pair-instability explosions can create
black holes with masses of $\sim$ 100 M$_{\odot}$.


title: Combinatorial negative curvature and triangulations of three-manifolds

abstract:
  We introduce and study local combinatorial conditions on a simplicial
complex, implying Gromov hyperbolicity of its universal cover. We apply the
theory to Thurston's problem on 5/6*-triangulations of 3-manifolds, providing a
new proof and generalizing the original result. We indicate further
applications.


title: Stable and unstable helices: Soap films in cylindrical tubes

abstract:
  Cox & Jones recently devised and studied an interesting variant of the
classical Plateau problem, a variant in which a helical soap film is confined
to a cylindrical tube with circular cross-section. Through experiments,
numerics, and some analysis, they found that the length and (inner) radius of
the tube strongly influence the equilibrium shape of the confined soap film. In
this paper, an area minimization problem associated with determining the shape
of the film is formulated and analyzed to determine which surfaces are local
minima. The connection between a functional inequality and the associated
eigenvalue problem plays an important role in the analysis. For helical films,
a more detailed analysis is carried out and stability conditions consistent
with the experimental and numerical results of Cox & Jones are obtained.


title:
Structural and optical properties of cobalt slanted columnar thin films
  conformally coated with graphene by chemical vapor deposition

abstract:
  A slanted cobalt sculptured columnar thin film was fabricated using glancing
angle deposition, and coated subsequently with graphene using a low temperature
chemical vapor deposition process. The graphene deposition process preserves
shape and geometry of the sculptured thin film, which was confirmed by scanning
electron microscopy. According to the Raman spectroscopy results, the graphene
coating is two to three monolayers thick and has a high defect concentration.
The graphene coverage within the sculptured thin film is determined from
generalized spectroscopic ellipsometry using a generalized anisotropic
Bruggeman effective medium approximation. The graphene coverage as well as
structural parameters of the thin film agree excellently with electron
microscopy and Raman observations, and suggest that the graphene coating is
conformal.


title:
Measurement of the B->Xsl+l- branching fraction and search for direct CP
  violation from a sum of exclusive final states

abstract:
  We present a measurement of the total branching fraction of the
flavor-changing neutral-current process B->Xsl+l-, along with partial branching
fractions in bins of dilepton and hadronic system (Xs) mass, using a sample of
471x10^6 Upsilon(4S)->BBbar events recorded with the BaBar detector at the
PEP-II e+e- collider. B mesons are reconstructed by combining a dilepton pair,
either e+e- or mu+mu-, with 10 different Xs final states containing exactly one
charged or neutral kaon, two or fewer charged pions, and at most one pi0. Using
a sum over these exclusive modes as the basis for extrapolation to the fully
inclusive rate, we measure a lepton-flavor-averaged inclusive branching
fraction BF(B->Xsl+l-) = (6.73 +0.70-0.64[stat] +0.34-0.25[exp syst] +/-
0.50[model syst])x10^-6 for m(l+l-)^2>0.1 GeV^2/c^4. Restricting our analysis
exclusively to final states from which a decaying B meson's flavor can be
inferred, we additionally report measurements of the direct CP asymmetry ACP in
bins of dilepton mass; over the full dilepton mass range, we find ACP=0.04 +/-
0.11 +/- 0.01$ for a lepton-flavor-averaged sample.


title: The Star Formation Rate of Molecular Clouds

abstract:
  We review recent advances in the analytical and numerical modeling of the
star formation rate in molecular clouds and discuss the available observational
constraints. We focus on molecular clouds as the fundamental star formation
sites, rather than on the larger-scale processes that form the clouds and set
their properties. Molecular clouds are shaped into a complex filamentary
structure by supersonic turbulence, with only a small fraction of the cloud
mass channeled into collapsing protostars over a free-fall time of the system.
In recent years, the physics of supersonic turbulence has been widely explored
with computer simulations, leading to statistical models of this fragmentation
process, and to the prediction of the star formation rate as a function of
fundamental physical parameters of molecular clouds, such as the virial
parameter, the rms Mach number, the compressive fraction of the turbulence
driver, and the ratio of gas to magnetic pressure. Infrared space telescopes,
as well as ground-based observatories have provided unprecedented probes of the
filamentary structure of molecular clouds and the location of forming stars
within them.


title:
The effect of guide-field and boundary conditions on collisionless
  magnetic reconnection in a stressed X-point collapse

abstract:
  Works of D. Tsiklauri, T. Haruki, Phys. of Plasmas, 15, 102902 (2008) and D.
Tsiklauri and T. Haruki, Phys. of Plasmas, 14, 112905, (2007) are extended by
inclusion of the out-of-plane magnetic (guide) field. In particular, magnetic
reconnection during collisionless, stressed $X$-point collapse for varying
out-of-plane guide-fields is studied using a kinetic, 2.5D, fully
electromagnetic, relativistic particle-in-cell numerical code. Cases for both
open and closed boundary conditions are investigated, where magnetic flux and
particles are lost and conserved respectively. It is found that reconnection
rates and out-of-plane currents in the $X$-point increase more rapidly and peak
sooner in the closed boundary case, but higher values are reached in the open
boundary case. The normalized reconnection rate is fast: 0.10-0.25. In the open
boundary case an increase of guide-field yields later onsets in the
reconnection peak rates, while in the closed boundary case initial peak rates
occur sooner but are suppressed. The reconnection current increases for low
guide-fields but then decreases similarly. In the open boundary case, for
guide-fields of the order of the in-plane magnetic field, the generation of
electron vortices occurs. Possible causes of the vortex generation, based on
the flow of particles in the diffusion region and localized plasma heating, are
discussed. Before peak reconnection onset, oscillations in the out-of-plane
electric field at the $X$-point are found, ranging in frequency from
approximately 1 to 2 $\omega_{pe}$ and coinciding with oscillatory
reconnection. These oscillations are found to be part of a larger wave pattern.
Mapping the out-of-plane electric field over time and applying 2D Fourier
transforms reveals that the waves predominantly correspond to the ordinary mode
and may correspond to observable radio waves such as solar radio burst fine
structure spikes.


title: Aspects of Jamming in Two-Dimensional Frictionless Systems

abstract:
  In this work we provide an overview of jamming transitions in two dimensional
systems focusing on the limit of frictionless particle interactions in the
absence of thermal fluctuations. We first discuss jamming in systems with short
range repulsive interactions, where the onset of jamming occurs at a critical
packing density and where certain quantities show a divergence indicative of
critical behavior. We describe how aspects of the dynamics change as the
jamming density is approached and how these dynamics can be explored using
externally driven probes. Different particle shapes can produce jamming
densities much lower than those observed for disk-shaped particles, and we show
how jamming exhibits fragility for some shapes while for other shapes this is
absent. Next we describe the effects of long range interactions and jamming
behavior in systems such as charged colloids, vortices in type-II
superconductors, and dislocations. We consider the effect of adding obstacles
to frictionless jamming systems and discuss connections between this type of
jamming and systems that exhibit depinning transitions. Finally, we discuss
open questions such as whether the jamming transition in all these different
systems can be described by the same or a small subset of universal behaviors,
as well as future directions for studies of jamming transitions in two
dimensional systems, such as jamming in self-driven or active matter systems.


title: A sharp cusp count for complex hyperbolic surfaces and related results

abstract:
  We derive a sharp cusp count for finite volume complex hyperbolic surfaces
which admit smooth toroidal compactifications. We use this result, and the
techniques developed in [DiC12], to study the geometry of cusped complex
hyperbolic surfaces and their compactifications.


title: Sign patterns of rational matrices with large rank

abstract:
  Let $A$ be a real matrix. The term rank of $A$ is the smallest number $t$ of
lines (that is, rows or columns) needed to cover all the nonzero entries of
$A$. We prove a conjecture of Li et al. stating that, if the rank of $A$
exceeds $t-3$, there is a rational matrix with the same sign pattern and rank
as those of $A$. We point out a connection of the problem discussed with the
Kapranov rank function of tropical matrices, and we show that the statement
fails to hold in general if the rank of $A$ does not exceed $t-3$.


title: Perturbed Gibbs Samplers for Synthetic Data Release

abstract:
  We propose a categorical data synthesizer with a quantifiable disclosure
risk. Our algorithm, named Perturbed Gibbs Sampler, can handle high-dimensional
categorical data that are often intractable to represent as contingency tables.
The algorithm extends a multiple imputation strategy for fully synthetic data
by utilizing feature hashing and non-parametric distribution approximations.
California Patient Discharge data are used to demonstrate statistical
properties of the proposed synthesizing methodology. Marginal and conditional
distributions, as well as the coefficients of regression models built on the
synthesized data are compared to those obtained from the original data.
Intruder scenarios are simulated to evaluate disclosure risks of the
synthesized data from multiple angles. Limitations and extensions of the
proposed algorithm are also discussed.


title:
Investigating early warning signs of oscillatory instability in
  simulated phasor measurements

abstract:
  This paper shows that the variance of load bus voltage magnitude in a small
power system test case increases monotonically as the system approaches a Hopf
bifurcation. This property can potentially be used as a method for monitoring
oscillatory stability in power grid using high-resolution phasor measurements.
Increasing variance in data from a dynamical system is a common sign of a
phenomenon known as critical slowing down (CSD). CSD is slower recovery of
dynamical systems from perturbations as they approach critical transitions.
Earlier work has focused on studying CSD in systems approaching voltage
collapse; In this paper, we investigate its occurrence as a power system
approaches a Hopf bifurcation.


title:
Using Kinematic Properties of Pre-Planetary Nebulae to Constrain Engine
  Paradigms

abstract:
  Some combination of binary interactions and accretion plausibly conspire to
produce the ubiquitous collimated outflows from planetary nebulae (PN) and
their presumed pre-planetary nebulae (PPN) precursors. But which accretion
engines are viable? The difficulty in observationally resolving the engines
warrants the pursuit of indirect constraints. We show how kinematic outflow
data for 19 PPN can be used to determine the minimum required accretion rates.
We consider main sequence (MS) and white dwarf (WD) accretors and five example
accretion rates inferred from published models to compare with the minima
derived from outflow momentum conservation. While our primary goal is to show
the method in anticipation of more data and better theoretical constraints,
taking the present results at face value already rule out modes of accretion:
Bondi-Hoyle Lyttleton (BHL) wind accretion and wind Roche lobe overflow
(M-WRLOF, based on Mira parameters) are too feeble for all 19/19 objects for a
MS accretor. For a WD accretor, BHL is ruled out for 18/19 objects and M-WRLOF
for 15/19 objects. Roche lobe overflow (RLOF) from the primary at the Red
Rectangle level can accommodate 7/19 objects, though RLOF modes with higher
accretion rates are not yet ruled out. Accretion modes operating from within
common envelope evolution can accommodate all 19 objects, if jet collimation
can be maintained. Overall, sub-Eddington rates for a MS accretor are
acceptable but 8/19 would require super-Eddington rates for a WD.


title: Amplification, Redundancy, and the Quantum Chernoff Information

abstract:
  Amplification was regarded, since the early days of quantum theory, as a
mysterious ingredient that endows quantum microstates with macroscopic
consequences, key to the "collapse of the wavepacket", and a way to avoid
embarrassing problems exemplified by Schr\"odinger's cat. Such a bridge between
the quantum microworld and the classical world of our experience was postulated
ad hoc in the Copenhagen Interpretation. Quantum Darwinism views amplification
as replication, in many copies, of the information about quantum states. We
show that such amplification is a natural consequence of a broad class of
models of decoherence, including the photon environment we use to obtain most
of our information. This leads to objective reality via the presence of robust
and widely accessible records of selected quantum states. The resulting
redundancy (the number of copies deposited in the environment) follows from the
Quantum Chernoff Information that quantifies the information transmitted by a
typical elementary subsystem of the environment.


title: Scalar Hairy Black Holes in General Dimensions

abstract:
  We obtain a class of asymptotic flat or (A)dS hairy black holes in
D-dimensional Einstein gravity coupled to a scalar with certain scalar
potential. For a given mass, the theory admits both the
Schwarzschild-Tangherlini and the hairy black holes with different temperature
and entropy, but satisfying the same first law of thermodynamics. For some
appropriate choice of parameters, the scalar potential can be expressed in
terms of a super-potential and it can arise in gauged supergravities. In this
case, the solutions develop a naked curvature singularity and become the
spherical domain walls. Uplifting the solutions to D=11 or 10, we obtain
solutions that can be viewed as spherical M-branes or D3-branes. We also add
electric charges to these hairy black holes. All these solutions contain no
scalar charges in that the first law of thermodynamics are unmodified. We also
try to construct new AdS black holes carrying scalar charges, with some
moderate success in that the charges are pre-fixed in the theory instead of
being some continuous integration constants.


title:
Gravitational waves from spinning compact object binaries: New
  post-Newtonian results

abstract:
  We report on recent results obtained in the post-Newtonian framework for the
modelling of the gravitational waves emitted by binary systems of spinning
compact objects (black holes and/or neutron stars). These new results are
obtained at the spin-orbit (linear-in-spin) level and solving Einstein's field
equations iteratively in harmonic coordinates as well as the multipolar
post-Newtonian formalism. The dynamics of the binary was tackled at the
next-to-next-to-leading order, corresponding to the 3.5 post-Newtonian (PN)
order for maximally spinning objects, and the result is found to be consistent
with a previously obtained reduced Hamiltonian in the ADM approach. The
corresponding contribution to the energy flux emitted by the binary was
obtained at the 3.5PN order, as well as the next-to-leading 4PN tail
contribution to this flux, an imprint of the non-linearity in the propagation
of the wave. These new terms can be used to build more accurate PN templates
for the next generation of gravitational wave detectors. We give an
illustrative estimate of the quantitative relevance of the new terms in the
orbital phasing of the binary.


title:
Activation-triggered subunit exchange between CaMKII holoenzymes
  facilitates the spread of kinase activity

abstract:
  The activation of the dodecameric Ca2+/calmodulin dependent kinase II
(CaMKII) holoenzyme is critical for the formation of memory. We now report that
CaMKII has a remarkable property, which is that activation of the holoenzyme
triggers the exchange of subunits with other holoenzymes, including unactivated
ones, enabling the calcium-independent phosphorylation and activation of new
subunits. We show, using a single-molecule TIRF microscopy technique, that the
exchange process is triggered by the activation of CaMKII, with the exchange
rate being modulated by phosphorylation of two residues in the
calmodulin-binding segment, Thr 305 and Thr 306. Based on these results, and on
the analysis of molecular dynamics simulations, we suggest that the
phosphorylated regulatory segment of CaMKII interacts with the central hub of
the holoenzyme and weakens its integrity, thereby promoting exchange. Our
results have implications for an earlier idea that subunit exchange in CaMKII
may have relevance for the storage of information resulting from brief
coincident stimuli during neuronal signaling.


title:
Clusters, Groups, and Filaments in the Chandra Deep Field-South up to
  Redshift 1

abstract:
  We present a comprehensive structure detection analysis of the 0.3 square
degree area of the MUSYC-ACES field which covers the Chandra Deep Field-South
(CDFS). Using a density-based clustering algorithm on the MUSYC and ACES
photometric and spectroscopic catalogues we find 62 over-dense regions up to
redshifts of 1, including, clusters, groups and filaments. All structures are
confirmed using the DBSCAN method, including the detection of nine structures
previously reported in the literature. We present a catalogue of all structures
present including their central position, mean redshift, velocity dispersions,
and classification based on their morphological and spectroscopic
distributions. In particular we find 13 galaxy clusters and 6 large
groups/small clusters. Comparison of these massive structures with published
XMM-Newton imaging (where available) shows that $80\%$ of these structures are
associated with diffuse, soft-band (0.4 - 1 keV) X-ray emission including
$90\%$ of all objects classified as clusters. The presence of soft-band X-ray
emission in these massive structures (${\rm M}_{200} \geq 4.9 \times 10^{13}
{\rm M}_{\odot}$) provides a strong independent confirmation of our methodology
and classification scheme. Nearly $60\%$ of the clusters, groups and filaments
are detected in the known enhanced density regions of the CDFS at
$z\simeq0.13$, $z\simeq0.52$, $0.68$, and $0.73$. Additionally, all of the
clusters, bar the most distant, are found in these over-dense redshifts
regions. Many of the clusters and groups exhibit signs of on-going formation
seen in their velocity distributions, position within the detected cosmic web
and in one case through the presence of tidally disrupted central galaxies
exhibiting trails of stars. These results all provide strong support for
hierarchical structure formation up to redshifts of 1.


title: Skolemization for Weighted First-Order Model Counting

abstract:
  First-order model counting emerged recently as a novel reasoning task, at the
core of efficient algorithms for probabilistic logics. We present a
Skolemization algorithm for model counting problems that eliminates existential
quantifiers from a first-order logic theory without changing its weighted model
count. For certain subsets of first-order logic, lifted model counters were
shown to run in time polynomial in the number of objects in the domain of
discourse, where propositional model counters require exponential time.
However, these guarantees apply only to Skolem normal form theories (i.e., no
existential quantifiers) as the presence of existential quantifiers reduces
lifted model counters to propositional ones. Since textbook Skolemization is
not sound for model counting, these restrictions precluded efficient model
counting for directed models, such as probabilistic logic programs, which rely
on existential quantification. Our Skolemization procedure extends the
applicability of first-order model counters to these representations. Moreover,
it simplifies the design of lifted model counting algorithms.


title:
Switching Mechanism in Single-Layer Molybdenum Disulfide Transistors: an
  Insight into Current Flow across Schottky Barriers

abstract:
  In this article, we study the properties of metal contacts to single-layer
molybdenum disulfide (MoS2) crystals, revealing the nature of switching
mechanism in MoS2 transistors. On investigating transistor behavior as contact
length changes, we find that the contact resistivity for metal/MoS2 junctions
is defined by contact area instead of contact width. The minimum gate dependent
transfer length is ~0.63 {\mu}m in the on-state for metal (Ti) contacted
single-layer MoS2. These results reveal that MoS2 transistors are Schottky
barrier transistors, where the on/off states are switched by the tuning the
Schottky barriers at contacts. The effective barrier heights for source and
drain barriers are primarily controlled by gate and drain biases, respectively.
We discuss the drain induced barrier narrowing effect for short channel
devices, which may reduce the influence of large contact resistance for MoS2
Schottky barrier transistors at the channel length scaling limit.


title: AGN torus properties with WISE

abstract:
  The Wide-field Infrared Survey Explorer (WISE) has scanned the entire sky
with unprecedented sensitivity in four infrared bands, at 3.4, 4.6, 12, and 22
micron. The WISE Point Source Catalog contains more than 560 million objects,
among them hundreds of thousands of galaxies with Active Nuclei (AGN). While
type 1 AGN, owing to their bright and unobscured nature, are easy to detect and
constitute a rather complete and unbiased sample, their type 2 counterparts,
postulated by AGN unification, are not as straightforward to identify. Matching
the WISE catalog with known QSOs in the Sloan Digital Sky Survey we confirm
previous identification of the type 1 locus in the WISE color space. Using a
very large database of the popular CLUMPY torus models, we find the colors of
the putative type 2 counterparts, and also, for the first time, predict their
number vs. flux relation that can be expected to be observed in any given WISE
color range. This will allow us to put statistically very significant
constraints on the torus parameters. Our results are a successful test of the
AGN unification scheme.


title:
Metric spaces nonembeddable into Banach spaces with the Radon-Nikod\'ym
  property and thick families of geodesics

abstract:
  We show that a geodesic metric space which does not admit bilipschitz
embeddings into Banach spaces with the Radon-Nikod\'ym property does not
necessarily contain a bilipschitz image of a thick family of geodesics. This is
done by showing that any thick family of geodesics is not Markov convex, and
comparing this result with results of Cheeger-Kleiner, Lee-Naor, and Li. The
result contrasts with the earlier result of the author that any Banach space
without the Radon-Nikod\'ym property contains a bilipschitz image of a thick
family of geodesics.


title: On Shift Dynamics For Cyclically Presented Groups

abstract:
  For group presentations with cyclic symmetry, there is a connection between
asphericity and the dynamics of the shift automorphism. For the class of groups
$G_n(k,l)$ described by the cyclic presentations $\mathcal{P}_n(k,l) =
(x_i:x_ix_{i+k}x_{i+l}\ (i \mod n))$ and studied extensively by G. Williams and
M. Edjvet \cite{EdjvetWilliams}, the shift acts freely on the nonidentity
elements of $G_n(k,l)$ if and only if the presentation $\mathcal{P}_n(k,l)$ is
combinatorially aspherical in the sense of \cite{CCH}. The shift has a
nonidentity fixed point precisely when $G_n(k,l)$ is finite.


title:
Effects of Long-Range Interactions on Magnetic Excitations and Phase
  Transition on a Magnetically Frustrated Square Lattice

abstract:
  We investigate the effects of long-range interaction on the magnetic
excitations and the competition between magnetic phases on a frustrated square
lattice. Applying the spin wave theory and assisted with symmetry analysis, we
obtain analytical expression for spin wave spectrum of competing Neel and (pi,
0) stripe states of systems containing any-order long-range interactions. In
the specific case of long-range interactions with power-law decay, we found
surprisingly that staggered long-range interaction suppresses quantum
fluctuation and enlarges the ordered moment, especially in the Neel state, and
thus extends its phase boundary to the stripe state. Our findings only
illustrate the rich possibilities of the roles of long-range interactions, and
advocate future investigations in other magnetic systems with different
structures of interactions.


title: Locally Lipschitz graph property for lines

abstract:
  On a non-compact, smooth, connected, boundaryless, complete Riemannian
manifold $(M,g)$, one can define its ideal boundary by rays (or equivalently,
Busemann functions). From the viewpoint of Mather theory, boundary elements
could be regarded as the static classes of Aubry sets, and thus lines should be
think as the semi-statics curves connecting different static classes. In Mather
theory, one core property is Lipschitz graph property for Aubry sets and for
some kind of semi-static curves. In this article, we prove a such kind of
result for a set of lines which connect the same pair of boundary elements.


title:
Scaling properties of the chiral phase transition in the low density
  region of two-flavor QCD with improved Wilson fermions

abstract:
  We study scaling behavior of a chiral order parameter in the low density
region, performing a simulation of two-flavor QCD with improved Wilson quarks.
The scaling behavior of the chiral order parameter defined by a Ward-Takahashi
identity agrees with the scaling function of the three-dimensional O(4) spin
model at zero chemical potential. We extend the scaling study to finite density
QCD. Applying the reweighting method and calculating derivatives of the chiral
order parameter with respect to the chemical potential, the scaling properties
of the chiral phase transition are discussed in the low density region. We
moreover calculate the curvature of the phase boundary of the chiral phase
transition in the temperature and chemical potential plane assuming the O(4)
scaling relation.


title: Detecting Parameter Symmetries in Probabilistic Models

abstract:
  Probabilistic models often have parameters that can be translated, scaled,
permuted, or otherwise transformed without changing the model. These symmetries
can lead to strong correlation and multimodality in the posterior distribution
over the model's parameters, which can pose challenges both for performing
inference and interpreting the results. In this work, we address the automatic
detection of common problematic model symmetries. To do so, we introduce local
symmetries, which cover many common cases and are amenable to automatic
detection. We show how to derive algorithms to detect several broad classes of
local symmetries. Our algorithms are compatible with probabilistic programming
constructs such as arrays, for loops, and if statements, and they scale to
models with many variables.


title:
Probing the local environment of two-dimensional ordered vacancy
  structures in Ga2SeTe2 via aberration-corrected electron microscopy

abstract:
  There has been considerable interest in chalcogenide alloys with high
concentrations of native vacancies that lead to properties desirable for
thermoelectric and phase-change materials. Recently, vacancy ordering has been
identified as the mechanism for metal-insulator transitions observed in
GeSb2Te4 and an unexpectedly low thermal conductivity in Ga2Te3. Here, we
report the direct observation of vacancy ordering in Ga2SeTe2 utilizing
aberration-corrected electron microscopy. Images reveal a cation-anion dumbbell
inversion associated with the accommodation of vacancy ordering across the
entire crystal. The result is a striking example of the interplay between
native defects and local structure.


title: Three-dimensional braids and their descriptions

abstract:
  The notion of a braid is generalized into two and three dimensions.
Two-dimensional braids are described by braid monodromies or graphics called
charts. In this paper we introduce the notion of curtains, and show that
three-dimensional braids are described by braid monodromies or curtains.


title:
Using Coronal Loops to Reconstruct the Magnetic Field of an Active
  Region Before and After a Major Flare

abstract:
  The shapes of solar coronal loops are sensitive to the presence of electrical
currents that are the carriers of the nonpotential energy available for
impulsive activity. We use this information in a new method for modeling the
coronal magnetic field of AR 11158 as a nonlinear force-free field (NLFFF). The
observations used are coronal images around time of major flare activity on
2011/02/15, together with the surface line-of-sight magnetic field
measurements. The data are from the Helioseismic and Magnetic Imager and
Atmospheric Imaging Assembly (HMI and AIA, respectively) onboard the Solar
Dynamics Observatory (SDO). The model fields are constrained to approximate the
coronal loop configurations as closely as possible, while also subject to the
force-free constraints. The method does not use transverse photospheric
magnetic field components as input, and is thereby distinct from methods for
modeling NLFFFs based on photospheric vector magnetograms. We validate the
method using observations of AR 11158 at a time well before major flaring, and
subsequently review the field evolution just prior to and following an X2.2
flare and associated eruption. The models indicate that the energy released
during the instability is about $1\times10^{32}$ erg, consistent with what is
needed to power such a large eruptive flare. Immediately prior to the eruption
the model field contains a compact sigmoid bundle of twisted flux that is not
present in the post-eruption models, which is consistent with the observations.
The core of that model structure is twisted by $\approx0.9$ full turns about
its axis.


title:
Longitudinal variations of positive dayside ionospheric storms related
  to recurrent geomagnetic storms

abstract:
  We have performed an analysis of case events and statistics of positive
ionospheric storms in the dayside region of the equatorial ionization anomaly
during recurrent geomagnetic storms (RGSs), which dominate in geomagnetic and
ionospheric conditions on the declining phase of solar activity in 2004 to
2008. It is shown that total electron content (TEC) has a tendency to minimize
before the beginning of RGSs and to peak 3 to 4 days after, i.e. on the RGS
recovery phase produced by high-intensity long-duration continuous auroral
activity. The maximum of TEC coincides with the maximum of solar wind velocity
within high-speed solar wind streams. An analysis of electron content vertical
profiles, derived from two independent methods using ionosondes and
COSMIC/FORMOSAT-3 radio occultation, showed that in the maximum of an
ionospheric storm on 28 March 2008, the F2 layer thickens, NmF2 increases by
~50% and hmF2 elevates by a few tens of kilometers. The response of positive
ionospheric storms to solar, heliospheric and geomagnetic drivers reveals a
prominent longitudinal asymmetry. In the longitudinal range from -90 deg to 90
deg, the solar illumination plays a major role, and in the range from 90 deg to
-120 deg, the influence of heliospheric and geomagnetic drivers becomes
significant. The highest correlations of the TEC enhancements with the
heliospheric and geomagnetic drivers were found during December - February
period (r increased from ~ 0.3 to ~0.5). We speculate that the dynamics
controlling this might result from an effect of solar zenith angle, storm-time
effects of thermospheric Sum(O/N2) enhancement, and penetrating electric fields
of interplanetary and magnetospheric origin.


title:
On Spatial Transition Probabilities as Continuity Measures in
  Categorical Fields

abstract:
  Models of spatial transition probabilities, or equivalently, transiogram
models have been recently proposed as spatial continuity measures in
categorical fields. In this paper, properties of transiogram models are
examined analytically, and three important findings are reported. Firstly,
connections between the behaviors of auto-transiogram models near the origin
and the spatial distribution of the corresponding category are carefully
investigated. Secondly, it is demonstrated that for the indicators of excursion
sets of Gaussian random fields, most of the commonly used basic mathematical
forms of covariogram models are not eligible for transiograms in most cases; an
exception is the exponential distance-decay function and models that are
constructed from it. Finally, a kernel regression method is proposed for
efficient, non-parametric joint modeling of auto- and cross-transiograms, which
is particularly useful for situations where the number of categories is large.


title: Free boundary minimal annuli in convex three-manifolds

abstract:
  We prove the existence of free boundary minimal annuli inside suitably convex
subsets of three-dimensional Riemannian manifolds with nonnegative Ricci
curvature $-$ including strictly convex domains of the Euclidean space
$\mathbb{R}^3$.


title: A characterisation of projective unitary equivalence of finite frames

abstract:
  It is well known that two finite sequences of vectors in inner product spaces
are unitarily equivalent if and only if their respective inner products (Gram
matrices) are equal. Here we present a corresponding result for the projective
unitary equivalence of two sequences of vectors (lines) in inner product
spaces, i.e., that a finite number of (Bargmann) projective (unitary)
invariants are equal. This is based on an algorithm to recover the sequence of
vectors (up to projective unitary equivalence) from a small subset of these
projective invariants. We consider the implications for the characterisation of
SICs, MUBs and harmonic frames up to projective unitary equivalence. We also
extend our results to projective similarity of vectors.


title: Missing Value Imputation With Unsupervised Backpropagation

abstract:
  Many data mining and data analysis techniques operate on dense matrices or
complete tables of data. Real-world data sets, however, often contain unknown
values. Even many classification algorithms that are designed to operate with
missing values still exhibit deteriorated accuracy. One approach to handling
missing values is to fill in (impute) the missing values. In this paper, we
present a technique for unsupervised learning called Unsupervised
Backpropagation (UBP), which trains a multi-layer perceptron to fit to the
manifold sampled by a set of observed point-vectors. We evaluate UBP with the
task of imputing missing values in datasets, and show that UBP is able to
predict missing values with significantly lower sum-squared error than other
collaborative filtering and imputation techniques. We also demonstrate with 24
datasets and 9 supervised learning algorithms that classification accuracy is
usually higher when randomly-withheld values are imputed using UBP, rather than
with other methods.


title: A generalization of contact metric manifolds

abstract:
  We give a characterization of a contact metric manifold as a special almost
contact metric manifold and discuss an almost contact metric manifold which is
{a} natural generalization of the contact metric manifolds introduced by Y.
Tashiro.


title: Action and Vertices in the Worldine Formalism

abstract:
  Utilizing the worldline formalism we study the effects of demanding local
interactions on the corresponding vertex factor. We begin by reviewing the
familiar case of a relativistic particle in Minkowksi space, showing that
localization gives rise to the standard conservation of momentum at each
vertex. A generalization to curved geometry is then studied and a notion of
covariant Fourier transform is introduced to aid in the analysis. The vertex
factor is found to coincide with the one derived for flat spacetime. Next, we
apply this formalism to a loop immersed in a gravitational field, demonstrating
that the loop momenta is determined entirely by the external momenta. Finally,
we postulate that the semi--classical effects of quantum gravity on the Feynman
path integral can be accounted for by a modification to the vertex factor which
de-localizes the vertex. We study one particular Lorentz invariant
de-localization which, remarkably, has no effect on conservation of vertex
momenta.


title: Quantifying Comparisons of Threshold Resummations

abstract:
  We explore similarities and differences between widely-used threshold
resummation formalisms, employing electroweak boson production as an
instructive example. Resummations based on both full QCD and soft-collinear
effective theory (SCET) share common underlying factorizations and resulting
evolution equations. The formalisms differ primarily in their choices of
boundary conditions for evolution, in moment space for many treatments based on
full QCD, and in momentum space for treatments based on soft-collinear
effective theory. At the level of factorized hadronic cross sections, these
choices lead to quite different expressions. Nevertheless, we can identify a
natural expansion for parton luminosity functions, in which SCET and full QCD
resummations agree for the first term, and for which subsequent terms provide
differences that are small in most cases. We also clarify the roles of the
non-leading resummation constants in the two formalisms, and observe a
relationship of the QCD resummation function $D(\alpha_s)$ to the web
expansion.


title: Continuous Learning: Engineering Super Features With Feature Algebras

abstract:
  In this paper we consider a problem of searching a space of predictive models
for a given training data set. We propose an iterative procedure for deriving a
sequence of improving models and a corresponding sequence of sets of non-linear
features on the original input space. After a finite number of iterations N,
the non-linear features become 2^N -degree polynomials on the original space.
We show that in a limit of an infinite number of iterations derived non-linear
features must form an associative algebra: a product of two features is equal
to a linear combination of features from the same feature space for any given
input point. Because each iteration consists of solving a series of convex
problems that contain all previous solutions, the likelihood of the models in
the sequence is increasing with each iteration while the dimension of the model
parameter space is set to a limited controlled value.


title:
A beamline for time-resolved extreme ultraviolet and soft x-ray
  spectroscopy

abstract:
  High harmonic generation is a convenient way to obtain extreme ultraviolet
light from table-top laser systems and the experimental tools to exploit this
simple and powerful light source for time-resolved spectroscopy are being
developed by several groups. For these applications, brightness and stability
of the high harmonic generation is a key feature. This article focuses on
practical aspects in the generation of extreme ultraviolet pulses with
ultrafast commercial lasers, namely generation parameters and online monitoring
as well as analysis of generation yield and stability.


title: Curvature identities on contact metric manifolds and their applications

abstract:
  We study curvature identities on contact metric manifolds on the geometry of
the corresponding almost K\"aehler cones, and we provide applications of the
derived curvature identities.


title: Fan-extensions in fragile matroids

abstract:
  If S is a set of matroids, then the matroid M is S-fragile if, for every
element e in E(M), either M\e or M/e has no minor isomorphic to a member of S.
Excluded-minor characterizations often depend, implicitly or explicitly, on
understanding classes of fragile matroids. In certain cases, when F is a
minor-closed class of S-fragile matroids, and N is in F, the only members of F
that contain N as a minor are obtained from N by increasing the length of fans.
We prove that if this is the case, then we can certify it with a finite
case-analysis. The analysis involves examining matroids that are at most two
elements larger than N.


title:
Some Improvements on Deep Convolutional Neural Network Based Image
  Classification

abstract:
  We investigate multiple techniques to improve upon the current state of the
art deep convolutional neural network based image classification pipeline. The
techiques include adding more image transformations to training data, adding
more transformations to generate additional predictions at test time and using
complementary models applied to higher resolution images. This paper summarizes
our entry in the Imagenet Large Scale Visual Recognition Challenge 2013. Our
system achieved a top 5 classification error rate of 13.55% using no external
data which is over a 20% relative improvement on the previous year's winner.


title:
Lack of water and endurance running could have caused the exponential
  growth in human brain: Point of no return model

abstract:
  Growth in brain volume is one of the most spectacular changes in the hominid
lineage. The anthropological community agrees on that point. No consensus,
however, has been reached on selection pressures contributing to that growth.
In that respect Martin (1984) can be invoked. In his review of size
relationships among primates he stated that despite the relationship between
brain size, body size and feeding behavior no single interpretation could be
provided that revealed the causality of such relationship.
  This paper deals with one specific aspect of hominid brain growth; the fact
that for most of the hominid period, growth in brain volume was exponential in
character. To the best of our knowledge, no attempt has been made to identify a
selection mechanism that can facilitate just the exponential features of that
growth (as distinct from any of its other characteristics). It is broadly
accepted that the dynamics of this growth were peculiar. Growth was very fast,
or even rapid in the evolutionary scale of time. The most profound evidence of
that opinion was expressed by Haldane that this dramatic increase in brain size
was the most rapid evolutionary change known to him.


title:
Microscopic Properties of the Heavy-Fermion Superconductor PuCoIn$_5$
  Explored by Nuclear Quadrupole Resonance

abstract:
  We report $^{115}$In nuclear quadrupolar resonance (NQR) measurements on the
heavy-fermion superconductor PuCoIn$_5$, in the temperature range $0.29{\rm
K}\leq T\leq 75{\rm K}$. The NQR parameters for the two crystallographically
inequivalent In sites are determined, and their temperature dependence is
investigated. A linear shift of the quadrupolar frequency with lowering
temperature below the critical value $T_c$ is revealed, in agreement with the
prediction for composite pairing. The nuclear spin-lattice relaxation rate
$T_1^{-1}(T)$ clearly signals a superconducting (SC) phase transition at
$T_c\simeq 2.3$K, with strong spin fluctuations, mostly in-plane, dominating
the relaxation process in the normal state near to $T_c$. Analysis of the
$T_1^{-1}$ data in the SC state suggests that PuCoIn$_5$ is a strong-coupling
$d$-wave superconductor.


title:
Electronic Structure of $\textrm{Fe}\textrm{Se}_{1-x}\textrm{Te}_x$
  Studied by X-ray Spectroscopy and Density Functional Theory

abstract:
  We study the electronic properties of the
$\textrm{Fe}\textrm{Se}_{1-x}\textrm{Te}_x$ system ($x=0$, 0.25, 0.5, 0.75, and
1) from the perspective of X-ray spectroscopy and density functional theory
(DFT). The analysis performed on the density of states reveals marked
differences in the distribution of the $5p$ states of Te for $x>0$. We think
that this finding can be associated with the fact that superconductivity is
suppressed in FeTe. Moreover, using resonant inelastic X-ray scattering, we
estimate the spin state of our system which can be correlated to the magnetic
order. We find that the spin state of the
$\textrm{Fe}\textrm{Se}_{1-x}\textrm{Te}_x$ system fluctuates, as a function of
$x$, between $S=0$ and $S=2$ with Fe in FeSe in the highest spin state.
Finally, our DFT calculations nicely reproduce the X-ray emission spectra
performed at the Fe $L$-edge (which probe the occupied states) and suggest that
the $\textrm{Fe}\textrm{Se}_{1-x}\textrm{Te}_x$ system can be considered at
most as a moderately correlated system.


title: B-meson spectroscopy in heavy hadron chiral perturbation theory

abstract:
  The theory of heavy meson masses, in which the symmetries of heavy and light
quarks are exploited, can be used to describe the low energy interaction among
heavy mesons to a better extent. The spin-flavor symmetry leads to many
interesting relations between the properties of hadrons containing a heavy
quark. The most direct consequences concern the spectroscopy of such states. We
use such symmetries to explore some of the states of B-meson and predictions
are found to be in agreement with the experimental data.


title: Focus Point Supersymmetry in Extended Gauge Mediation

abstract:
  We propose a small extenion of the minimal gauge mediation through the
combination of extended gauge mediation and conformal sequestering. We show
that the focus point supersymmetry can be realized naturally, and the
fine-tuning is signifcantly reduced compared to the minimal gauge mediation and
extended gauge mediation without focus point. The Higgs boson mass is around
125 GeV, the gauginos remain light, and the gluino is likely to be detected at
the next run of the LHC. However, the multi-TeV squarks is out of the reach of
the LHC. The numerical calculation for finetuning shows that this model remains
natural.


title: Diversities and the Geometry of Hypergraphs

abstract:
  The embedding of finite metrics in $\ell_1$ has become a fundamental tool for
both combinatorial optimization and large-scale data analysis. One important
application is to network flow problems in which there is close relation
between max-flow min-cut theorems and the minimal distortion embeddings of
metrics into $\ell_1$. Here we show that this theory can be generalized
considerably to encompass Steiner tree packing problems in both graphs and
hypergraphs. Instead of the theory of $\ell_1$ metrics and minimal distortion
embeddings, the parallel is the theory of diversities recently introduced by
Bryant and Tupper, and the corresponding theory of $\ell_1$ diversities and
embeddings which we develop here.


title:
Heavy-ion fusion cross sections of weakly bound $^{9}$Be on $^{27}$Al,
  $^{64}$Zn and tightly bound $^{16}$O on $^{64}$Zn target using Coulomb and
  proximity potential

abstract:
  The total fusion cross sections for the fusion of weakly bound $^{9}$Be on
$^{27}$Al and $^{64}$Zn targets at near and above the barrier have been
calculated using one dimensional barrier penetration model, taking scattering
potential as the sum of Coulomb and proximity potential and the calculated
values are compared with experimental data. For the purpose of comparison of
the fusion of weakly bound projectiles and strongly bound projectiles, the
total fusion cross sections for the reaction of tightly bound nucleus $^{16}$O
on $^{64}$Zn have also been computed using a similar procedure. The calculated
values of total fusion cross sections in all cases are compared with coupled
channel calculations using the code CCFULL. The computed cross sections using
Coulomb and proximity potential explain the fusion reactions well in both cases
of weakly bound and strongly bound projectiles. Reduced reaction cross sections
for the systems $^{9}$Be + $^{27}$Al, $^{9}$Be+ $^{64}$Zn and $^{16}$O +
$^{64}$Zn have also been described.


title:
Radio-frequency reflectometry on an undoped AlGaAs/GaAs single electron
  transistor

abstract:
  Radio frequency reflectometry is demonstrated in a sub-micron undoped
AlGaAs/GaAs device. Undoped single electron transistors (SETs) are attractive
candidates to study single electron phenomena due to their charge stability and
robust electronic properties after thermal cycling. However these devices
require a large top-gate which is unsuitable for the fast and sensitive radio
frequency reflectometry technique. Here we demonstrate rf reflectometry is
possible in an undoped SET.


title: Selective but not Ramsey

abstract:
  We give a partial answer to the following question of Dobrinen: For a given
topological Ramsey space $\mathcal{R}$, are the notions of selective for
$\mathcal{R}$ and Ramsey for $\mathcal{R}$ equivalent? Every topological Ramsey
space $\mathcal{R}$ has an associated notion of Ramsey ultrafilter for
$\mathcal{R}$ and selective ultrafilter for $\mathcal{R}$ (see
\cite{MijaresSelective}). If $\mathcal{R}$ is taken to be the Ellentuck space
then the two concepts reduce to the familiar notions of Ramsey and selective
ultrafilters on $\omega$; so by a well-known result of Kunen the two are
equivalent. We give the first example of an ultrafilter on a topological Ramsey
space that is selective but not Ramsey for the space, and in fact a countable
collection of such examples.
  For each positive integer $n$ we show that for the topological Ramsey space
$\mathcal{R}_{n}$ from \cite{Ramsey-Class2}, the notions of selective for
$\mathcal{R}_{n}$ and Ramsey for $\mathcal{R}_{n}$ are not equivalent. In
particular, we prove that forcing with a closely related space using
almost-reduction, adjoins an ultrafilter that is selective but not Ramsey for
$\mathcal{R}_{n}$. Moreover, we introduce a notion of finite product among
members of the family $\{\mathcal{R}_{n}: n<\omega\}$. We show that forcing
with closely related product spaces using almost-reduction, adjoins
ultrafilters that are selective but not Ramsey for these product topological
Ramsey spaces.


title:
Approximated Infomax Early Stopping: Revisiting Gaussian RBMs on Natural
  Images

abstract:
  We pursue an early stopping technique that helps Gaussian Restricted
Boltzmann Machines (GRBMs) to gain good natural image representations in terms
of overcompleteness and data fitting. GRBMs are widely considered as an
unsuitable model for natural images because they gain non-overcomplete
representations which include uniform filters that do not represent useful
image features. We have recently found that GRBMs once gain and subsequently
lose useful filters during their training, contrary to this common perspective.
We attribute this phenomenon to a tradeoff between overcompleteness of GRBM
representations and data fitting. To gain GRBM representations that are
overcomplete and fit data well, we propose a measure for GRBM representation
quality, approximated mutual information, and an early stopping technique based
on this measure. The proposed method boosts performance of classifiers trained
on GRBM representations.


title:
Catalog of narrow $C~IV$ absorption lines in BOSS (I): for quasars with
  $z_{em} \leq 2.4$

abstract:
  We have assembled absorption systems by visually identifying
$C~IV\lambda\lambda1548,1551$ absorption doublets in the quasar spectra of the
Baryon Oscillation Spectroscopic Survey (BOSS) one by one. This paper is the
first of the series work. In this paper, we concern quasars with relatively low
redshifts and high signal-to-noise ratios for their spectra, and hence we limit
our analysis on quasars with $z_{em}\le2.4$ and on the doublets with
$W_r\lambda1548\ge0.2$ \AA. Out of the more than 87,000 quasars in the Data
Release 9, we limit our search to 10,121 quasars that have the appropriate
redshifts and spectra with high enough signal-to-noise ratios to identify
narrow C IV absorption lines. Among them, 5,442 quasars are detected to have at
least one $C~IV\lambda\lambda1548,1551$ absorption doublet. We obtain a catalog
containing 8,368 $C~IV\lambda\lambda1548,1551$ absorption systems, whose
redshifts are within $z_{abs}=1.4544$ - $2.2805$. In this catalog, about
$33.7\%$ absorbers have $0.2$ \AA$\le W_r\lambda1548<0.5$ \AA, about $45.9\%$
absorbers have $0.5$ \AA$\le W_r\lambda1548<1.0$ \AA, about $19.2\%$ absorbers
have $1.0$ \AA$\le W_r\lambda1548<2.0$ \AA, and about $1.2\%$ absorbers have
$W_r\lambda1548\ge2.0$ \AA.


title:
Existence of variationally defined curves in complete Riemannian
  manifolds

abstract:
  We present a method for proving the existence of solutions to a class of one
dimensional variational problems. The method is demonstrated by two examples of
optimal interpolation problems which are motivated by engineering applications.
In each case we prove that the variational problem satisfies the Palais-Smale
condition and the existence of a minimal solution and lower bounds for the
number of stationary curves then follow.


title:
A renormalization group method for studying the early universe in the
  Lorentzian IIB matrix model

abstract:
  We propose a new method for studying the early universe in the Lorentzian
version of the IIB matrix model, which is considered to be a nonperturbative
formulation of superstring theory. This method is based on the idea of
renormalization group, and it enables us to study the time-evolution of the
universe for much longer time than in the previous work, which showed that the
SO(9) rotational symmetry is spontaneously broken down to SO(3) after a
"critical time". We demonstrate how this method works in a simplified model,
which is expected to capture the behaviors of the original model when the space
is not so large. In particular, we present clear evidence that the
three-dimensional space expands exponentially after the critical time in this
simplified model.


title:
Fundamental Symmetry Tests with Nucleons, Nuclei, and Atoms: A Snowmass
  Report

abstract:
  Present and prospective fundamental symmetry tests with nucleons, nuclei and
atoms are probing for possible new physics at the TeV scale and beyond. These
ongoing and proposed table-top as well as accelerator-based experiments are
thus a vital component of the Intensity Frontier. At the same time, these tests
provide increasingly sophisticated probes of long-distance strong interactions
that are responsible for the structure of nucleons and nuclei. In this
community report, some of the most compelling opportunities with nucleons,
nuclei and atoms are summarized, drawing largely on input received from the
nuclear and atomic physics communities. In particular, this report includes
many contributions submitted to two recent Intensity Frontier Workshops.


title: Robust Steganography Using LSB-XOR and Image Sharing

abstract:
  Hiding and securing the secret digital information and data that are
transmitted over the internet is of widespread and most challenging interest.
This paper presents a new idea of robust steganography using bitwise-XOR
operation between stego-key-image-pixel LSB (Least Significant Bit) value and
secret message-character ASCII-binary value (or, secret image-pixel value). The
stego-key-image is shared in dual-layer using odd-even position of each pixel
to make the system robust. Due to image sharing, the detection can only be done
with all the image shares.


title: L2 norm preserving flow in matrix geometry

abstract:
  In this paper, we study L2 norm preserving heat flow in matrix geometry. We
show that this flow preserves the operator convex property and enjoys the
entropy stability in any finite time. Interesting properties of this flow like
conserved trace free property are also derived.


title: Large-scale Multi-label Text Classification - Revisiting Neural Networks

abstract:
  Neural networks have recently been proposed for multi-label classification
because they are able to capture and model label dependencies in the output
layer. In this work, we investigate limitations of BP-MLL, a neural network
(NN) architecture that aims at minimizing pairwise ranking error. Instead, we
propose to use a comparably simple NN approach with recently proposed learning
techniques for large-scale multi-label text classification tasks. In
particular, we show that BP-MLL's ranking loss minimization can be efficiently
and effectively replaced with the commonly used cross entropy error function,
and demonstrate that several advances in neural network training that have been
developed in the realm of deep learning can be effectively employed in this
setting. Our experimental results show that simple NN models equipped with
advanced techniques such as rectified linear units, dropout, and AdaGrad
perform as well as or even outperform state-of-the-art approaches on six
large-scale textual datasets with diverse characteristics.


title: Polarizing Double Negation Translations

abstract:
  Double-negation translations are used to encode and decode classical proofs
in intuitionistic logic. We show that, in the cut-free fragment, we can
simplify the translations and introduce fewer negations. To achieve this, we
consider the polarization of the formul{\ae}{} and adapt those translation to
the different connectives and quantifiers. We show that the embedding results
still hold, using a customized version of the focused classical sequent
calculus. We also prove the latter equivalent to more usual versions of the
sequent calculus. This polarization process allows lighter embeddings, and
sheds some light on the relationship between intuitionistic and classical
connectives.


title:
Crystal-chemistry and short-range order of fluoro-edenite and
  fluoro-pargasite: a combined x-ray diffraction and ftir spectroscopic
  approach

abstract:
  In this study we address the crystal-chemistry of a set of five samples of
F-rich amphiboles from the Franklin marble (USA), using a combination of
microchemical (EMPA), SREF, and FTIR spectroscopy methods. The EMPA data show
that three samples fall into the compositional field of fluoro-edenite whereas
two samples are enriched in high-charged C cations, and must be classified as
fluoro-pargasite. Mg is by far the dominant C cation, Ca is the dominant B
cation (with BNa in the range 0.00-0.05 apfu, atoms per formula unit), and Na
is the dominant A cation, with A0 (vacancy) in the range 0.07-0.21 apfu; WF is
in the range 1.18-1.46 apfu. SREF data show that: TAl is completely ordered at
the T(1) site; the M(1) site is occupied only by divalent cations (Mg and
Fe2+); CAl is disordered between the M(2) and M(3) sites; ANa is ordered at the
A(m) site, as expected in F-rich compositions. The FTIR spectra show a triplet
of intense and sharp components at ~ 3690, 3675, and 3660 cm-1, which are
assigned to the amphibole, and the systematic presence of two very broad
absorptions at 3560 and 3430 cm-1. These latter are assigned, on the basis of
polarized measurements and FPA imaging, to chlorite-type inclusions within the
amphibole matrix. Up to eight components can be fitted to the spectra; band
assignment based on previous literature on similar compositions shows that CAl
is disordered over the M(2) and M(3) sites, thus supporting the SREF
conclusions based on the <M-O> bond distance analysis. The measured frequencies
are typical of O-H groups pointing toward Si-O(7)-Al tetrahedral linkages, thus
allowing to characterize the SRO (short-range-order) of TAl in the double
chain. Accordingly, the spectra show that in the fluoroedenite/pargasite
structure, the T cations, Si and Al, are ordered in such a way that Si- O(7)-Si
linkages regularly alternate with Si-O(7)-Al linkages along the double chain.


title:
Crossover behavior of the thermal conductance and Kramers' transition
  rate theory

abstract:
  Kramers' theory frames chemical reaction rates in solution as reactants
overcoming a barrier in the presence of friction and noise. For weak coupling
to the solution, the reaction rate is limited by the rate at which the solution
can restore equilibrium after a subset of reactants have surmounted the barrier
to become products. For strong coupling, there are always sufficiently
energetic reactants. However, the solution returns many of the intermediate
states back to the reactants before the product fully forms. Here, we
demonstrate that the thermal conductance displays an analogous physical
response to the friction and noise that drive the heat current through a
material or structure. A crossover behavior emerges where the thermal
reservoirs dominate the conductance at the extremes and only in the
intermediate region are the intrinsic properties of the lattice manifest. Not
only does this shed new light on Kramers' classic turnover problem, this result
is significant for the design of devices for thermal management and other
applications, as well as the proper simulation of transport at the nanoscale.


title:
On the Behaviour of the Backward Interpretation of Feynman-Kac Formulae
  under Verifiable Conditions

abstract:
  In the following article we consider the time-stability associated to the
sequential Monte Carlo (SMC) estimate of the backward interpretation of
Feynman-Kac Formulae. This is particularly of interest in the context of
performing smoothing for hidden Markov models (HMMs). We prove a central limit
theorem (CLT) under weaker assumptions than adopted in the literature. We then
show that the associated asymptotic variance expression, for additive
functionals grows at most linearly in time, under hypotheses that are weaker
than those currently existing in the literature. The assumptions are verified
for some state-space models.


title:
Dual Layer Textual Message Cryptosystem with Randomized Sequence of
  Symmetric Key

abstract:
  This paper introduces a new concept of textual message encryption and
decryption through a pool of randomized symmetric key and the dual layer
cryptosystem with the concept of visual cryptography and steganography. A
textual message is converted into two image slides, and the images are
encrypted through two different randomized sequences of symmetric key. The
decryption is done in the reverse way. The encrypted images are decrypted by
those two symmetric keys. The decrypted image slides are merged together and
converted into textual message. Here the image sharing is done through the
concept of visual cryptography and the textual message to image conversion is
done through the concept of steganography.


title: Graphene Grown on Ge(001) from Atomic Source

abstract:
  Among the many anticipated applications of graphene, some - such as
transistors for Si microelectronics - would greatly benefit from the
possibility to deposit graphene directly on a semiconductor grown on a Si
wafer. We report that Ge(001) layers on Si(001) wafers can be uniformly covered
with graphene at temperatures between 800{\deg}C and the melting temperature of
Ge. The graphene is closed, with sheet resistivity strongly decreasing with
growth temperature, weakly decreasing with the amount of deposited C, and
reaching down to 2 kOhm/sq. Activation energy of surface roughness is low
(about 0.66 eV) and constant throughout the range of temperatures in which
graphene is formed. Density functional theory calculations indicate that the
major physical processes affecting the growth are: (1) substitution of Ge in
surface dimers by C, (2) interaction between C clusters and Ge monomers, and
(3) formation of chemical bonds between graphene edge and Ge(001), and that the
processes 1 and 2 are surpassed by CH$_{2}$ surface diffusion when the C atoms
are delivered from CH$_{4}$. The results of this study indicate that graphene
can be produced directly at the active region of the transistor in a process
compatible with the Si technology.


title:
Supersymmetric Fits after the Higgs Discovery and Implications for Model
  Building

abstract:
  The data from the first run of the LHC at 7 and 8 TeV, together with the
information provided by other experiments such as precision electroweak
measurements, flavour measurements, the cosmological density of cold dark
matter and the direct search for the scattering of dark matter particles in the
LUX experiment, provide important constraints on supersymmetric models.
Important information is provided by the ATLAS and CMS measurements of the mass
of the Higgs boson, as well as the negative results of searches at the LHC for
events with missing transverse energy accompanied by jets, and the LHCb and CMS
measurements off BR($B_s \to \mu^+ \mu^-$). Results are presented from
frequentist analyses of the parameter spaces of the CMSSM and NUHM1. The global
$\chi^2$ functions for the supersymmetric models vary slowly over most of the
parameter spaces allowed by the Higgs mass and the missing transverse energy
search, with best-fit values that are comparable to the $\chi^2$ for the
Standard Model. The $95\%$ CL lower limits on the masses of gluinos and squarks
allow significant prospects for observing them during the LHC runs at higher
energies.


title: The Novikov-Veselov Equation: Theory and Computation

abstract:
  Recent progress in the theory and computation for the Novikov-Veselov (NV)
equation is reviewed with initial potentials decaying at infinity, focusing
mainly on the zero-energy case. The inverse scattering method for the
zero-energy NV equation is presented in the context of Manakov triples,
treating initial data of conductivity type rigorously. Special closed-form
solutions are presented, including multisolitons, ring solitons, and breathers.
The computational inverse scattering method is used to study zero-energy
exceptional points and the relationship between supercritical, critical, and
subcritical potentials.


title: Note on the equation of state of geometric dark-energy in f(R) gravity

abstract:
  We focus on the analysis of three inequivalent equations of state of
geometric dark energy in $f(R)$ cosmology that have been considered in the past
and discuss their differences, advantages and drawbacks.


title: On the Proxy Identity Crisis

abstract:
  A proxy, in general, is an object mediating access to an arbitrary target
object. The proxy is then intended to be used in place of the target object.
Ideally, a proxy is not distinguishable from other objects. Running a program
with a proxy leads to the same outcome as running the program with the target
object. Even though the approach provides a lot of power to the user, proxies
come with a limitation. Because a proxy, wrapping a target object, is a new
object and different from its target, the interposition changes the behaviour
of some core components. For distinct proxies the double == and triple ===
equal operator returns false, even if the target object is the same. More
precisely, the expected result depends on use case. To overcome this limitation
we will discuss alternatives.


title: AdS Black Holes from Duality in Gauged Supergravity

abstract:
  We study and utilize duality transformations in a particular STU-model of
four dimensional gauged supergravity. This model is a truncation of the de
Wit-Nicolai N=8 theory and as such has a lift to eleven-dimensional
supergravity on the seven-sphere. Our duality group is $U(1)^3$ and while it
can be applied to any solution of this theory, we consider the known
asymptotically AdS$_4$, supersymmetric black holes and focus on duality
transformations which preserve supersymmetry. For static black holes we
generalize the supersymmetric solutions of Cacciatori and Klemm from three
magnetic charges to include two additional electric charges and argue that this
is co-dimension one in the full space of supersymmetric static black holes in
the STU-model. These new static black holes have nontrivial profiles for
axions. For rotating black holes, we generalize the known two-parameter
supersymmetric solution to include an additional parameter which represents
scalar hair. When lifted to M-theory, these black holes correspond to the near
horizon geometry of a stack of BPS rotating M2-branes, spinning on an $S^7$
which is fibered non-trivially over a Riemann surface.


title: Noncommutative real algebraic geometry of Kazhdan's property (T)

abstract:
  It is well-known that a finitely generated group $\Gamma$ has Kazhdan's
property (T) if and only if the Laplacian element $\Delta$ in ${\mathbb
R}[\Gamma]$ has a spectral gap. In this paper, we prove that this phenomenon is
witnessed in ${\mathbb R}[\Gamma]$. Namely, $\Gamma$ has property (T) if and
only if there are a constant $\kappa>0$ and a finite sequence $\xi_1,...,\xi_n$
in ${\mathbb R}[\Gamma]$ such that $\Delta^2-\kappa\Delta = \sum_i
\xi_i^*\xi_i$. This result suggests the possibility of finding new examples of
property (T) groups by solving equations in ${\mathbb R}[\Gamma]$, possibly
with an assist of computers.


title:
Revisiting $1^{-+}$ and $0^{++}$ light hybrids from Monte-Carlo based
  QCD sum rules

abstract:
  In this paper, we re-analyze the $1^{-+}$ and $0^{++}$ light hybrids from QCD
sum rules with a Monte-Carlo based uncertainty analysis. With $30\%$
uncertainties in the accepted central values for QCD condensates and other
input parameters, we obtain a prediction on $1^{-+}$ hybrid mass of $1.71 \pm
0.22$\,GeV, which covers the mass of $\pi_1(1600)$. However, the $0^{++}$
hybrid mass prediction is more than 4\,GeV, which is far away from any known
$a_0$ meson. We also study the correlations between the input and output
parameters of QCD sum rules.


title: Orbital angular momentum from marginals of quadrature distributions

abstract:
  We set forth a method to analyze the orbital angular momentum of a light
field. Instead of using the canonical formalism for the conjugate pair
angle-angular momentum, we model this latter variable by the superposition of
two independent harmonic oscillators along two orthogonal axes. By describing
each oscillator by a standard Wigner function, we derive, via a consistent
change of variables, a comprehensive picture of the orbital angular momentum.
We compare with previous approaches and show how this method works in some
relevant examples.


title:
Asynchronous Adaptation and Learning over Networks --- Part I: Modeling
  and Stability Analysis

abstract:
  In this work and the supporting Parts II [2] and III [3], we provide a rather
detailed analysis of the stability and performance of asynchronous strategies
for solving distributed optimization and adaptation problems over networks. We
examine asynchronous networks that are subject to fairly general sources of
uncertainties, such as changing topologies, random link failures, random data
arrival times, and agents turning on and off randomly. Under this model, agents
in the network may stop updating their solutions or may stop sending or
receiving information in a random manner and without coordination with other
agents. We establish in Part I conditions on the first and second-order moments
of the relevant parameter distributions to ensure mean-square stable behavior.
We derive in Part II expressions that reveal how the various parameters of the
asynchronous behavior influence network performance. We compare in Part III the
performance of asynchronous networks to the performance of both centralized
solutions and synchronous networks. One notable conclusion is that the
mean-square-error performance of asynchronous networks shows a degradation only
of the order of $O(\nu)$, where $\nu$ is a small step-size parameter, while the
convergence rate remains largely unaltered. The results provide a solid
justification for the remarkable resilience of cooperative networks in the face
of random failures at multiple levels: agents, links, data arrivals, and
topology.


title: Flavor changing neutral currents in top quark production and decay

abstract:
  Top quark flavor changing neutral current (FCNC) interactions are highly
suppressed in the Standard Model. Therefore, any large signal of FCNCs will
indicate the existence of new interactions. In this paper, searches for FCNC
interactions in top quark production and decay at the Tevatron and LHC are
presented. FCNC searches in $t\rightarrow qZ$ and $t\rightarrow Hq$ decays, and
in top quark production in $pp\rightarrow t+j$, $pp\rightarrow t+Z$ are
summarized. Effect of top quark FCNCs on single top quark cross-section, and
the searches for same-sign top quark pair production through FCNCs are also
described. None of the searches yielded positive results and exclusion limits
on branching rations, coupling strengths and cross-sections are obtained.
Future prospects of FCNC searches are also briefly discussed.


title: Discrete analogues of Kakeya problems

abstract:
  This thesis investigates two problems that are discrete analogues of two
harmonic analytic problems which lie in the heart of research in the field.
  More specifically, we consider discrete analogues of the maximal Kakeya
operator conjecture and of the recently solved endpoint multilinear Kakeya
problem, by effectively shrinking the tubes involved in these problems to
lines, thus giving rise to the problems of counting joints and multijoints with
multiplicities. In fact, we effectively show that, in $\mathbb{R}^3$, what we
expect to hold due to the maximal Kakeya operator conjecture, as well as what
we know in the continuous case due to the endpoint multilinear Kakeya theorem
by Guth, still hold in the discrete case.
  In particular, let $\mathfrak{L}$ be a collection of $L$ lines in
$\mathbb{R}^3$ and $J$ the set of joints formed by $\mathfrak{L}$, that is, the
set of points each of which lies in at least three non-coplanar lines of
$\mathfrak{L}$. It is known that $|J|=O(L^{3/2})$ (first proved by Guth and
Katz). For each joint $x\in J$, let the multiplicity $N(x)$ of $x$ be the
number of triples of non-coplanar lines through $x$. We prove here that
$$\sum_{x\in J} N(x)^{1/2}=O(L^{3/2}), $$while we also extend this result to
real algebraic curves in $\mathbb{R}^3$ of uniformly bounded degree, as well as
to curves in $\mathbb{R}^3$ parametrized by real univariate polynomials of
uniformly bounded degree.
  The multijoints problem is a variant of the joints problem, involving three
finite collections of lines in $\mathbb{R}^3$; a multijoint formed by them is a
point that lies in (at least) three non-coplanar lines, one from each
collection.
  We finally present some results regarding the joints problem in different
field settings and higher dimensions.


title:
Asymptotic optimal location of facilities in a competition between
  population and industries

abstract:
  We consider the problem of optimally locating a given number $k$ of points in
${\mathbb R}^n$ for an integral cost function which takes into account two
measures $\varphi^+$ and $\varphi^-$. The points represent for example new
industrial facilities that have to be located, the measure $\varphi^+$
representing in this case already existing industries that want to be close to
the new ones, and $\varphi^-$ representing private citizens who want to stay
far away. The asymptotic analysis as $k\to\infty$ is performed, providing the
asymptotic density of optimal locations.


title:
Asynchronous Adaptation and Learning over Networks - Part II:
  Performance Analysis

abstract:
  In Part I \cite{Zhao13TSPasync1}, we introduced a fairly general model for
asynchronous events over adaptive networks including random topologies, random
link failures, random data arrival times, and agents turning on and off
randomly. We performed a stability analysis and established the notable fact
that the network is still able to converge in the mean-square-error sense to
the desired solution. Once stable behavior is guaranteed, it becomes important
to evaluate how fast the iterates converge and how close they get to the
optimal solution. This is a demanding task due to the various asynchronous
events and due to the fact that agents influence each other. In this Part II,
we carry out a detailed analysis of the mean-square-error performance of
asynchronous strategies for solving distributed optimization and adaptation
problems over networks. We derive analytical expressions for the mean-square
convergence rate and the steady-state mean-square-deviation. The expressions
reveal how the various parameters of the asynchronous behavior influence
network performance. In the process, we establish the interesting conclusion
that even under the influence of asynchronous events, all agents in the
adaptive network can still reach an $O(\nu^{1 + \gamma_o'})$ near-agreement
with some $\gamma_o' > 0$ while approaching the desired solution within
$O(\nu)$ accuracy, where $\nu$ is proportional to the small step-size parameter
for adaptation.


title:
Asynchronous Adaptation and Learning over Networks - Part III:
  Comparison Analysis

abstract:
  In Part II [3] we carried out a detailed mean-square-error analysis of the
performance of asynchronous adaptation and learning over networks under a
fairly general model for asynchronous events including random topologies,
random link failures, random data arrival times, and agents turning on and off
randomly. In this Part III, we compare the performance of synchronous and
asynchronous networks. We also compare the performance of decentralized
adaptation against centralized stochastic-gradient (batch) solutions. Two
interesting conclusions stand out. First, the results establish that the
performance of adaptive networks is largely immune to the effect of
asynchronous events: the mean and mean-square convergence rates and the
asymptotic bias values are not degraded relative to synchronous or centralized
implementations. Only the steady-state mean-square-deviation suffers a
degradation in the order of $\nu$, which represents the small step-size
parameters used for adaptation. Second, the results show that the adaptive
distributed network matches the performance of the centralized solution. These
conclusions highlight another critical benefit of cooperation by networked
agents: cooperation does not only enhance performance in comparison to
stand-alone single-agent processing, but it also endows the network with
remarkable resilience to various forms of random failure events and is able to
deliver performance that is as powerful as batch solutions.


title: Distributed Interior-point Method for Loosely Coupled Problems

abstract:
  In this paper, we put forth distributed algorithms for solving loosely
coupled unconstrained and constrained optimization problems. Such problems are
usually solved using algorithms that are based on a combination of
decomposition and first order methods. These algorithms are commonly very slow
and require many iterations to converge. In order to alleviate this issue, we
propose algorithms that combine the Newton and interior-point methods with
proximal splitting methods for solving such problems. Particularly, the
algorithm for solving unconstrained loosely coupled problems, is based on
Newton's method and utilizes proximal splitting to distribute the computations
for calculating the Newton step at each iteration. A combination of this
algorithm and the interior-point method is then used to introduce a distributed
algorithm for solving constrained loosely coupled problems. We also provide
guidelines on how to implement the proposed methods efficiently and briefly
discuss the properties of the resulting solutions.


title: Supermassive Cosmic String Compactifications

abstract:
  The space-time dimensions transverse to a static straight cosmic string with
a sufficiently large tension (supermassive cosmic strings) are compact and
typically have a singularity at a finite distance form the core. In this paper,
we discuss how the presence of multiple supermassive cosmic strings in the 4D
Abelian-Higgs model can induce the spontaneous compactification of the
transverse space and explicitly construct solutions where the gravitational
background becomes regular everywhere. We discuss the embedding of this model
in N=1 supergravity and show that some of these solutions are half-BPS, in the
sense that they leave unbroken half of the supersymmetries of the model.


title: A new representation for multivariate tail probabilities

abstract:
  Existing theory for multivariate extreme values focuses upon
characterizations of the distributional tails when all components of a random
vector, standardized to identical margins, grow at the same rate. In this
paper, we consider the effect of allowing the components to grow at different
rates, and characterize the link between these marginal growth rates and the
multivariate tail probability decay rate. Our approach leads to a whole class
of univariate regular variation conditions, in place of the single but
multivariate regular variation conditions that underpin the current theories.
These conditions are indexed by a homogeneous function and an angular
dependence function, which, for asymptotically independent random vectors,
mirror the role played by the exponent measure and Pickands' dependence
function in classical multivariate extremes. We additionally offer an
inferential approach to joint survivor probability estimation. The key feature
of our methodology is that extreme set probabilities can be estimated by
extrapolating upon rays emanating from the origin when the margins of the
variables are exponential. This offers an appreciable improvement over existing
techniques where extrapolation in exponential margins is upon lines parallel to
the diagonal.