title: The Pan-STARRS Moving Object Processing System

abstract:
  We describe the Pan-STARRS Moving Object Processing System (MOPS), a modern
software package that produces automatic asteroid discoveries and
identifications from catalogs of transient detections from next-generation
astronomical survey telescopes. MOPS achieves > 99.5% efficiency in producing
orbits from a synthetic but realistic population of asteroids whose
measurements were simulated for a Pan-STARRS4-class telescope. Additionally,
using a non-physical grid population, we demonstrate that MOPS can detect
populations of currently unknown objects such as interstellar asteroids.
  MOPS has been adapted successfully to the prototype Pan-STARRS1 telescope
despite differences in expected false detection rates, fill-factor loss and
relatively sparse observing cadence compared to a hypothetical Pan-STARRS4
telescope and survey. MOPS remains >99.5% efficient at detecting objects on a
single night but drops to 80% efficiency at producing orbits for objects
detected on multiple nights. This loss is primarily due to configurable MOPS
processing limits that are not yet tuned for the Pan-STARRS1 mission.
  The core MOPS software package is the product of more than 15 person-years of
software development and incorporates countless additional years of effort in
third-party software to perform lower-level functions such as spatial searching
or orbit determination. We describe the high-level design of MOPS and essential
subcomponents, the suitability of MOPS for other survey programs, and suggest a
road map for future MOPS development.


title:
An almost existence theorem for non-contractible periodic orbits in
  cotangent bundles

abstract:
  Assume M is a closed connected smooth manifold and H:T^*M->R a smooth proper
function bounded from below. Suppose the sublevel set {H<d} contains the zero
section and \alpha is a non-trivial homotopy class of free loops in M. Then for
almost every s>=d the level set {H=s} carries a periodic orbit z of the
Hamiltonian system (T^*M,\omega_0,H) representing \alpha.
  Examples show that the condition that {H<d} contains M is necessary and
almost existence cannot be improved to everywhere existence.


title:
Source Separation using Regularized NMF with MMSE Estimates under GMM
  Priors with Online Learning for The Uncertainties

abstract:
  We propose a new method to enforce priors on the solution of the nonnegative
matrix factorization (NMF). The proposed algorithm can be used for denoising or
single-channel source separation (SCSS) applications. The NMF solution is
guided to follow the Minimum Mean Square Error (MMSE) estimates under Gaussian
mixture prior models (GMM) for the source signal. In SCSS applications, the
spectra of the observed mixed signal are decomposed as a weighted linear
combination of trained basis vectors for each source using NMF. In this work,
the NMF decomposition weight matrices are treated as a distorted image by a
distortion operator, which is learned directly from the observed signals. The
MMSE estimate of the weights matrix under GMM prior and log-normal distribution
for the distortion is then found to improve the NMF decomposition results. The
MMSE estimate is embedded within the optimization objective to form a novel
regularized NMF cost function. The corresponding update rules for the new
objectives are derived in this paper. Experimental results show that, the
proposed regularized NMF algorithm improves the source separation performance
compared with using NMF without prior or with other prior models.


title: Stellar Collisions and Blue Straggler Stars in Dense Globular Clusters

abstract:
  Blue straggler stars (BSS) are abundantly observed in all Galactic globular
clusters (GGC) where data exist. However, observations alone cannot reveal the
relative importance of various formation channels or the typical formation
times for this well studied population of anomalous stars. Using a
state-of-the-art H\'enon-type Monte Carlo code that includes all relevant
physical processes, we create 128 models with properties typical of the
observed GGCs. These models include realistic numbers of single and binary
stars, use observationally motivated initial conditions, and span large ranges
in central density, concentration, binary fraction, and mass. Their properties
can be directly compared with those of observed GGCs. We can easily identify
the BSSs in our models and determine their formation channels and birth times.
We find that for central densities above ~10^3 Msun/pc^3 the dominant formation
channel is stellar collisions while for lower density clusters, mass transfer
in binaries provides a significant contribution (up to ~ 60% in our models).
The majority of these collisions are binary-mediated, occurring during 3-body
and 4-body interactions. As a result a strong correlation between the specific
frequency of BSSs and the binary fraction in a cluster can be seen in our
models. We find that the number of BSSs in the core shows only a weak
correlation with the collision rate estimator \Gamma traditionally used by
observers, in agreement with the latest Hubble Space Telescope (ACS) data.
Using an idealized "full mixing" prescription for collision products, our
models indicate that the BSSs observed today may have formed several Gyrs ago.
However, denser clusters tend to have younger (~1 Gyr) BSSs.


title:
Microscopic Mechanism of Stereochemically Active Lone Pair Studied from
  Orbital Selective External Potential Calculation

abstract:
  The nature of the stereochemically active lone pair has long been in debate.
Here, by application of our recently developed orbital selective external
potential (OSEP) method, we have studied the microscopic mechanism of
stereochemically active lone pairs in various compounds. The OSEP method allows
us to shift the energy level of specific atomic orbital, therefore is helpful
to identify unambiguously the role of this orbital to the chemical and physical
properties of the system we are interested in. Our numerical results, with
compelling proofs, demonstrate that the on-site mixing of cation valence s
orbital with the nominally empty p orbitals of the same subshell is crucial to
the formation of lone pair, whereas the anion p orbital has only small effect.
Our detailed investigation of Sn and Pb monochalcogenides show that structures
of these systems have significant effects on lone pairs. In return, the
formation of lone pair, which can be controlled by our OSEP method, could
result in structural instabilities of Sn and Pb monochalcogenides.


title: Quantum recurrence of a subspace and operator-valued Schur functions

abstract:
  A notion of monitored recurrence for discrete-time quantum processes was
recently introduced in [Commun. Math. Phys., DOI 10.1007/s00220-012-1645-2]
(see also arXiv:1202.3903) taking the initial state as an absorbing one. We
extend this notion of monitored recurrence to absorbing subspaces of arbitrary
finite dimension.
  The generating function approach leads to a connection with the well-known
theory of operator-valued Schur functions. This is the cornerstone of a
spectral characterization of subspace recurrence that generalizes some of the
main results in the above mentioned paper. The spectral decomposition of the
unitary step operator driving the evolution yields a spectral measure, which we
project onto the subspace to obtain a new spectral measure that is purely
singular iff the subspace is recurrent, and consists of a pure point spectrum
with a finite number of masses precisely when all states in the subspace have a
finite expected return time.
  This notion of subspace recurrence also links the concept of expected return
time to an Aharonov-Anandan phase that, in contrast to the case of state
recurrence, can be non-integer. Even more surprising is the fact that averaging
such geometrical phases over the absorbing subspace yields an integer with a
topological meaning, so that the averaged expected return time is always a
rational number. Moreover, state recurrence can occasionally give higher return
probabilities than subspace recurrence, a fact that reveals once more the
counterintuitive behavior of quantum systems.
  All these phenomena are illustrated with explicit examples, including as a
natural application the analysis of site recurrence for coined walks.


title:
Nonlinear optical effects of ultrahigh-Q silicon photonic nanocavities
  immersed in superfluid helium

abstract:
  Photonic nanocavities are a key component in many applications because of
their capability of trapping and storing photons and enhancing interactions of
light with various functional materials and structures. The maximal number of
photons that can be stored in silicon photonic cavities is limited by the
free-carrier and thermo-optic effects at room temperature. To reduce such
effects, we performed the first experimental study of optical nonlinearities in
ultrahigh-Q silicon disk nanocavities at cryogenic temperatures in a superfluid
helium environment. At elevated input power, the cavity transmission spectra
exhibit distinct blue-shifted bistability behavior when temperature crosses the
liquid helium lambda point. At even lower temperatures, the spectra restore to
symmetric Lorentzian shapes. Under this condition, we obtain a large stored
intracavity photon number of about 40,000, which is limited ultimately by the
local helium phase transition. These new discoveries are explained by
theoretical calculations and numerical simulations.


title:
Symmetric solutions to dispersionless 2D Toda hierarchy, Hurwitz numbers
  and conformal dynamics

abstract:
  We explicitly construct the series expansion for a certain class of solutions
to the 2D Toda hierarchy in the zero dispersion limit, which we call symmetric
solutions. We express the Taylor coefficients through some universal
combinatorial constants and find recurrence relations for them. These results
are used to obtain new formulas for the genus 0 double Hurwitz numbers. They
can also serve as a starting point for a constructive approach to the Riemann
mapping problem and the inverse potential problem in 2D.


title:
Homology-based Distributed Coverage Hole Detection in Wireless Sensor
  Networks

abstract:
  Homology theory provides new and powerful solutions to address the coverage
problems in wireless sensor networks (WSNs). They are based on algebraic
objects, such as Cech complex and Rips complex. Cech complex gives accurate
information about coverage quality but requires a precise knowledge of the
relative locations of nodes. This assumption is rather strong and hard to
implement in practical deployments. Rips complex provides an approximation of
Cech complex. It is easier to build and does not require any knowledge of nodes
location. This simplicity is at the expense of accuracy. Rips complex can not
always detect all coverage holes. It is then necessary to evaluate its
accuracy. This work proposes to use the proportion of the area of undiscovered
coverage holes as performance criteria. Investigations show that it depends on
the ratio between communication and sensing radii of a sensor. Closed-form
expressions for lower and upper bounds of the accuracy are also derived. For
those coverage holes which can be discovered by Rips complex, a homology-based
distributed algorithm is proposed to detect them. Simulation results are
consistent with the proposed analytical lower bound, with a maximum difference
of 0.5%. Upper bound performance depends on the ratio of communication and
sensing radii. Simulations also show that the algorithm can localize about 99%
coverage holes in about 99% cases.


title:
Charge density distribution and optical response of the LaAlO3/SrTiO3
  interface

abstract:
  We present calculations of the charge density profile, subband occupancy and
ellipsometry spectra of the electron gas at the LaAlO3/SrTiO3 interface. The
calculations employ self-consistent Hartree and random phase approximations, a
tight binding parametrization of the band structure and a model for the optical
phonon of SrTiO3. The dependence of the spatial structure and occupancy of
subbands on the magnitude of the polarization charge at the interface and the
dielectric function is determined. The interface-confined subbands may be
labelled by the symmetry (xy, xz, or yz) of the Ti d-orbitals from which they
mainly derive. The xy-derived band nearest the interface contains the major
proportion of the electronic charge, but a large number of more distant,
slightly occupied xy-derived bands are also found. Depending on the magnitude
of the polarization charge, zero, one, or two xz/yz derived subbands are found.
When present, these xz/yz bands give the dominant contribution to the
long-distance tail of the interface charge. The response to applied ac electric
fields polarized parallel and perpendicular to the interface is calculated and
the results are presented in terms of ellipsometry angles. Two features are
found: a dip in the spectrum near the LO feature of the STO phonon and a peak
at the higher energy. We show that the form and magnitude of the dip is related
to the Drude response of carriers moving in the plane of the interface while
the peak arises from the plasmon excitation of the xz and yz electrons. The
relation of the features of the subband occupancies and the in-plane
conductivities is given.


title: The arrow of time and the nature of spacetime

abstract:
  This paper extends the work of a previous paper [arXiv:1208.2611] on the flow
of time, to consider the origin of the arrow of time. It proposes that a `past
condition' cascades down from cosmological to micro scales, being realized in
many microstructures and setting the arrow of time at the quantum level by
top-down causation. This physics arrow of time then propagates up, through
underlying emergence of higher level structures, to geology, astronomy,
engineering, and biology. The appropriate space-time picture to view all this
is an emergent block universe (`EBU'), that recognizes the way the present is
different from both the past and the future. This essential difference is the
ultimate reason the arrow of time has to be the way it is.


title:
Accelerated density matrix expansions for Born-Oppenheimer molecular
  dynamics

abstract:
  An accelerated polynomial expansion scheme to construct the density matrix in
quantum mechanical molecular dynamics simulations is proposed. The scheme is
based on recursive density matrix expansions, e.g. [Phys. Rev. B. 66 (2002), p.
155115], which are accelerated by a scale-and-fold technique [J. Chem. Theory
Comput. 7 (2011), p. 1233]. The acceleration scheme requires interior
eigenvalue estimates, which may be expensive and cumbersome to come by. Here we
show how such eigenvalue estimates can be extracted from the recursive
expansion by a simple and robust procedure at a negligible computational cost.
Our method is illustrated with density functional tight-binding
Born-Oppenheimer molecular dynamics simulations, where the computational effort
is dominated by the density matrix construction. In our analysis we identify
two different phases of the recursive polynomial expansion, the conditioning
and purification phases, and we show that the acceleration represents an
improvement of the conditioning phase, which typically gives a significant
reduction of the computational cost.


title: Quarkonia production in the STAR experiment

abstract:
  In this proceedings the recent STAR results of $J/\psi$ and $\Upsilon$
production in $p+p$, $d$+Au and Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
at mid-rapidity are reported. $J/\psi$ $p_{T}$ spectra in $p+p$ and Au+Au
collisions for both low and high $p_{T}$ are shown. $J/\psi$ nuclear
modification factor ($R_{AA}$) in $d$+Au and Au+Au collisions and $\Upsilon$
$R_{AA}$ in Au+Au collisions are reported. Also, $J/\psi$ polarization in $p+p$
collisions and $J/\psi$ $v_{2}$ for semi-central Au+Au collisions are
presented.


title:
Ab Initio Calculations of Even Oxygen Isotopes with Chiral Two- Plus
  Three-Nucleon Interactions

abstract:
  We formulate the In-Medium Similarity Renormalization Group (IM-SRG) for
open-shell nuclei using a multi-reference formalism based on a generalized Wick
theorem introduced in quantum chemistry. The resulting multi-reference IM-SRG
(MR-IM-SRG) is used to perform the first ab initio study of even oxygen
isotopes with chiral NN and 3N Hamiltonians, from the proton to the neutron
drip lines. We obtain an excellent reproduction of experimental ground-state
energies with quantified uncertainties, which is validated by results from the
Importance-Truncated No-Core Shell Model and the Coupled Cluster method. The
agreement between conceptually different many-body approaches and experiment
highlights the predictive power of current chiral two- and three-nucleon
interactions, and establishes the MR-IM-SRG as a promising new tool for ab
initio calculations of medium-mass nuclei far from shell closures.


title: Quantum coding in non-inertial frames

abstract:
  The capacity of accelerated channel is investigated for different classes of
initial states. It is shown that, the capacities of the travelling channels
depend on the frame in which the accelerated channels are observed in and the
initial shared state between the partners. In some frames, the capacities decay
as the accelerations of both qubit increase. The decay rate is larger if the
partners are initially share a maximum entangled state. The possibility of
using the accelerated quantum channels to perform quantum coding protocol is
discussed. The amount of decoded information is quantified for different cases,
where it decays as the partner's accelerations increase to reach its minimum
bound. This minimum bound depends on the initial shared states and it is large
for maximum entangled state.


title:
Gaussianity revisited: Exploring the Kibble-Zurek mechanism with
  superconducting rings

abstract:
  In this paper we use spontaneous flux production in annular superconductors
to shed light on the Kibble-Zurek scenario. In particular, we examine the
effects of finite size and external fields, neither of which is directly
amenable to the KZ analysis. Supported by 1D and 3D simulations, the properties
of a superconducting ring are seen to be well represented by analytic Gaussian
approximations which encode the KZ scales indirectly. Experimental results for
annuli in the presence of external fields corroborate these findings.


title: Defects in Cohomological Gauge Theory and Donaldson-Thomas Invariants

abstract:
  Donaldson-Thomas theory on a Calabi-Yau can be described in terms of a
certain six-dimensional cohomological gauge theory. We introduce a certain
class of defects in this gauge theory which generalize surface defects in four
dimensions. These defects are associated with divisors and are defined by
prescribing certain boundary conditions for the gauge fields. We discuss
generalized instanton moduli spaces when the theory is defined with a defect
and propose a generalization of Donaldson-Thomas invariants. These invariants
arise by studying torsion free coherent sheaves on Calabi-Yau varieties with a
certain parabolic structure along a divisor, determined by the defect. We
discuss the case of the affine space as a concrete example. In this case the
moduli space of parabolic sheaves admits an alternative description in terms of
the representation theory of a certain quiver. The latter can be used to
compute the invariants explicitly via equivariant localization. We also briefly
discuss extensions of our work to other higher dimensional field theories.


title: Magnetic Polarization and Fermi Surface Instability: Case of YbRh2Si2

abstract:
  We report thermoelectric and resitivity measurements of antiferromagnetic
heavy fermion compound YRh2Si2 at low temperatures down and under high magnetic
field. At low temperature, the thermoelectric power and the resistivity present
several distinct anomalies as a function of field around H_0 ~ 9.5 T when the
magnetic polarization reaches a critical value. The anomalies are accompanied
with a change of sign from negative at low magnetic field to positive at high
field (H>H_0) and are resulting from a Lifshitz-type topological transition of
the Fermi surface. A logarithmic divergence of S/T at T \to 0 K just above H_0
(H=11.5 T) is quite comparable to the well known divergence of S/T in the
temperature range above the antiferromagnetic order at H=0 T referred to as non
Fermi liquid behavior. The transition will be compared to the well
characterized Fermi surface change in CeRu2Si2 at its pseudo-metamagnetic
transition.


title: Progress Toward Understanding Baryon Resonances

abstract:
  The composite nature of baryons manifests itself in the existence of a rich
spectrum of excited states, in particular in the important mass region 1-2 GeV
for the light-flavoured baryons. The properties of these resonances can be
identified by systematic investigations using electromagnetic and strong
probes, primarily with beams of electrons, photons, and pions. After decades of
research, the fundamental degrees of freedom underlying the baryon excitation
spectrum are still poorly understood. The search for hitherto undiscovered but
predicted resonances continues at many laboratories around the world. Recent
results from photo- and electroproduction experiments provide intriguing
indications for new states and shed light on the structure of some of the known
nucleon excitations. The continuing study of available data sets with
consideration of new observables and improved analysis tools have also called
into question some of the earlier findings in baryon spectroscopy. Other
breakthrough measurements have been performed in the heavy-baryon sector, which
has seen a fruitful period in recent years, in particular at the B factories
and the Tevatron. First results from the LHC indicate rapid progress in the
field of bottom baryons. In this review, we discuss the recent experimental
progress and give an overview of theoretical approaches.


title: Functions concerned with divisors of order $r$

abstract:
  N. Minculete has introduced a concept of divisors of order $r$: integer
$d=p_1^{b_1}\cdots p_k^{b_k} $ is called a divisor of order $r$ of
$n=p_1^{a_1}\cdots p_k^{a_k}$ if $d \mid n$ and $b_j\in\{r, a_j\}$ for
$j=1,\ldots,k$. One can consider respective divisor function $\tau^{(r)}$ and
sum-of-divisors function $\sigma^{(r)}$.
  In the present paper we investigate the asymptotic behaviour of $\sum_{n\le
x} \tau^{(r)}(n)$ and $\sum_{n\le x} \sigma^{(r)}(n)$. We also provide
conditional estimates under Riemann hypothesis.


title: Background fitness, eco-evolutionary feedbacks and the Hawk-Dove game

abstract:
  This paper further develops work from a previous article which introduced a
new way of modelling evolutionary game models with an emphasis on ecological
realism, concerned with how ecological factors determine payoffs in
evolutionary games. The current paper is focused on the impact of selectively
neutral factors (i.e. those that are the same for all strategies), such as
background fitness and a neutral density dependence on game dynamics. In the
previous paper background mortality was modelled by post-reproductive mortality
describing aggregated mortality between game interactions. In this paper a
novel approach to the modelling of background fitness, based on different
occurrence rates (intensities) of game interactions and background events is
presented. It is shown that the new method is more realistic and natural for
dynamic models than the method used in the previous paper. The previous method
in effect produces biased trajectories, but it is compatible with the new
approach at the restpoints. Also in this paper a rigorous stability analysis of
the restpoints of the dynamics is presented. It is shown that the stability or
instability of the restpoints, can be explained by a mechanism of
eco-evolutionary feedback. The results obtained are illustrated by a Hawk-Dove
game example.


title: Cohomology and Versal Deformations of Hom-Leibniz algebras

abstract:
  The purpose of this paper is to study global deformations of Hom-Leibniz
algebras. We introduce a cohomology for Hom-Leibniz algebras with values in a
Hom-module, characterize versal deformations and provide examples.


title:
Unitarization of uniformly bounded subgroups in finite von Neumann
  algebras

abstract:
  This note will present a new proof of the fact that every uniformly bounded
group of invertible elements in a finite von Neumann algebra is similar to a
unitary group. The proof involves metric geometric arguments in the
non-positively curved space of positive invertible operators of the algebra; in
1974 Vasilescu and Zsido proved this result using the Ryll-Nardzewsky fixed
point theorem.


title:
The statistically anisotropic curvature perturbation generated by
  f(\phi)^2 F^2

abstract:
  The inflaton might be coupled to a gauge field through a term f^2(\phi)
F_\mu\nu F^\mu\nu. If f \propto a^{-2} where a(t) is the scale factor, the
perturbation \delta W of the gauge field generates a potentially observable
statistically anisotropic contribution to the primordial curvature perturbation
during slow-roll inflation. The spectrum and bispectrum of this contribution
have been calculated using the in-in formalism of quantum field theory. We give
a simpler and more complete calculation using only the classical perturbations.
The results suggest that either the entire curvature perturbation \zeta (both
the statistically isotropic and anisotropic parts) is generated during
slow-roll inflation, or else it is generated afterwards.


title:
A Microscopic and Spectroscopic View of Quantum Tunneling of
  Magnetization

abstract:
  This chapter takes a microscopic view of quantum tunneling of magnetization
(QTM) in single-molecule magnets (SMMs), focusing on the interplay between
exchange and anisotropy. Careful consideration is given to the relationship
between molecular symmetry and the symmetry of the spin Hamiltonian that
dictates QTM selection rules. Higher order interactions that can modify the
usual selection rules are shown to be very sensitive to the exchange strength.
In the strong coupling limit, the spin Hamiltonian possess rigorous $D_{2h}$
symmetry (or $C_{\infty}$ in high-symmetry cases). In the case of weaker
exchange, additional symmetries may emerge through mixing of excited spin
states into the ground state. Group theoretic arguments are introduced to
support these ideas, as are extensive results of magnetization hysteresis and
electron paramagnetic resonance measurements.


title:
Rayleigh-Taylor Instability in a Relativistic Fireball on a Moving
  Computational Grid

abstract:
  We numerically calculate the growth and saturation of the Rayleigh-Taylor
instability caused by the deceleration of relativistic outflows with Lorentz
factor {\Gamma} = 10, 30, and 100. The instability generates turbulence whose
scale exhibits strong dependence on Lorentz factor, as only modes with angular
size smaller than 1/{\Gamma} can grow. We develop a simple diagnostic to
measure the kinetic energy in turbulent fluctuations, and calculate a ratio of
turbulent kinetic energy to thermal energy of .03 in the region affected by the
instability. Although our numerical calculation does not include magnetic
fields, we argue that small scale turbulent dynamo amplifies magnetic fields to
nearly this same fraction, giving a ratio of magnetic to thermal energy of ~
.01, to within a factor of two. The instability completely disrupts the contact
discontinuity between the ejecta and the swept up circumburst medium. The
reverse shock is stable, but is impacted by the Rayleigh-Taylor instability,
which strengthens the reverse shock and pushes it away from the forward shock.
The forward shock front is unaffected by the instability, but Rayleigh-Taylor
fingers can penetrate of order 10% of the way into the energetic region behind
the shock during the two-shock phase of the explosion. We calculate afterglow
emission from the explosion and find the reverse shock emission peaks at a
later time due to its reduced Lorentz factor and modified density and pressure
at the shock front. These calculations are performed using a novel numerical
technique that includes a moving computational grid. The moving grid is
essential as it maintains contact discontinuities to high precision and can
easily evolve flows with extremely large Lorentz factors.


title: Stray-field imaging of magnetic vortices with a single diamond spin

abstract:
  Despite decades of advances in magnetic imaging, obtaining direct,
quantitative information with nanometer scale spatial resolution remains an
outstanding challenge. Recently, a new technique has emerged that employs a
single nitrogen-vacancy (NV) defect in diamond as an atomic-size magnetometer.
Although NV magnetometry promises significant advances in magnetic imaging, the
effectiveness of the technique, when applied to realistic magnetic
nanostructures, remains to be demonstrated. Here we use a scanning NV
magnetometer to image a magnetic vortex, which is one of the most iconic object
of nanomagnetism, owing to the small size (~10 nm) of the vortex core. We
report three-dimensional, vectorial, and quantitative measurements of the stray
magnetic field emitted by a vortex in a ferromagnetic square dot, including the
detection of the vortex core. We find excellent agreement with micromagnetic
simulations, both for regular vortex structures and for higher-order
magnetization states. These experiments establish scanning NV magnetometry as a
practical and unique tool for fundamental studies in nanomagnetism.


title: Revealing CFFs and GPDs from experimental measurements

abstract:
  We report on the status of the phenomenological access of generalized parton
distributions from photon and meson electroproduction off proton. Thereby, we
emphasize the role of HERMES data for deeply virtual Compton scattering, which
allows us to map various asymmetries into the space of Compton form factors.


title:
Approximative solution of the spin free Hamiltonian involving only
  scalar potential for the quark-antiquark system

abstract:
  In earlier papers [3,4,5,6] Gursey et al. showed development of a bilocal
baryon-meson field from two quark-antiquark fields. The Hamiltonian in the case
of vanishing quark masses was shown to have a very good agreement with
experiments [5]. The theory for vanishing mass was solved using Confluent
Hypergeometric functions [6].
  In this paper I construct the normalized wave function for the spin-free
Hamiltonian with light quark masses (only up to the first order of the mass of
quark). I develop the new kind of special function theory in mathematics that
generalize all existing theories of Confluent Hypergeometric types. I call it
the 'Grand Confluent Hypergeometric (GCH) Function.' My solution produces
previously unknown extra "hidden" radial quantum numbers relevant for
description of supersymmetry and for generating new mass formulas.
  This paper is 1st out of 10 in series "Special functions and three term
recurrence formula (3TRF)". See section 6 for all the papers in the series. The
next paper in the series describes generalization of three term recurrence
relation in linear ordinary differential equations and its applications [8].


title: The Holography of F-maximization

abstract:
  We find new supersymmetric backgrounds of ${\cal N} = 8$ gauged supergravity
in four Euclidean dimensions that are dual to deformations of ABJM theory on
$S^3$. The deformations encode the most general choice of $U(1)_R$ symmetry
used to define the theory on $S^3$. We work within an ${\cal N} = 2$ truncation
of the ${\cal N} = 8$ supergravity theory obtained via a group theory argument.
We find perfect agreement between the $S^3$ free energy computed from our
supergravity backgrounds and the previous field theory computations of the same
quantity based on supersymmetric localization and matrix model techniques.


title: Anomalous processes and leading logarithms

abstract:
  Present status of odd-intrinsic sector of low energy QCD is summarized. The
two-photon decay of neutral pion is shortly discussed and its connection with
the pion decay constant is analysed. A theoretical tool, the leading-log
calculation is also presented, its connection with anomalous sector shown and
some new results given.


title: QCD Flux Tubes and Anomaly Inflow

abstract:
  We apply the Callan-Harvey anomaly inflow mechanism to the study of QCD
(chromoelectric) flux tubes, quark (pair)-creation and chiral magnetic effect,
using new variables from the Cho-Faddeev-Niemi decomposition of the gauge
potential. A phenomenological description of chromoelectric flux tubes is
obtained by studying a gauged Nambu-Jona-Lasinio effective Lagrangian, derived
from the original QCD Lagrangian. At the quantum level, quark condensates in
the QCD vacuum may form a vortex-like structure in a chromoelectric flux tube.
Quark zero modes trapped in the vortex are chiral and lead to a two-dimensional
gauge anomaly. To cancel it an effective Chern-Simons coupling is needed and
hence a topological charge density term naturally appears.


title: A new proof for the Erd\H{o}s-Ko-Rado Theorem for the alternating group

abstract:
  A subset $S$ of the alternating group on $n$ points is {\it intersecting} if
for any pair of permutations $\pi,\sigma$ in $S$, there is an element $i\in
\{1,\dots,n\}$ such that $\pi(i)=\sigma(i)$. We prove that if $S$ is
intersecting, then $|S|\leq \frac{(n-1)!}{2}$. Also, we prove that if $n \geq
5$, then the only sets $S$ that meet this bound are the cosets of the
stabilizer of a point of $\{1,\dots,n\}$.


title:
Torque Saturation in Bipedal Robotic Walking through Control Lyapunov
  Function Based Quadratic Programs

abstract:
  This paper presents a novel method for directly incorporating user-defined
control input saturations into the calculation of a control Lyapunov function
(CLF)-based walking controller for a biped robot. Previous work by the authors
has demonstrated the effectiveness of CLF controllers for stabilizing periodic
gaits for biped walkers, and the current work expands on those results by
providing a more effective means for handling control saturations. The new
approach, based on a convex optimization routine running at a 1 kHz control
update rate, is useful not only for handling torque saturations but also for
incorporating a whole family of user-defined constraints into the online
computation of a CLF controller. The paper concludes with an experimental
implementation of the main results on the bipedal robot MABEL.


title: Unions of Lebesgue spaces and $A_1$ majorants

abstract:
  We study two questions. When does a function belong to the union of Lebesgue
spaces and when does a function have an $A_1$ majorant? We show these questions
are fundamentally related. For functions restricted to a fixed cube we prove
that the following are equivalent: a function belongs to $L^p$ for some $p>1$;
the function has an $A_1$ majorant; for any $p>1$ the function belongs to
$L^p_w$ for some $A_p$ weight $w$. We also examine the case of functions
defined on ${\mathbb R}^n$ and give characterizations of the union of $L^p_w$
over $w$ in $A_p$ and when a function has an $A_1$ majorant on all of ${\mathbb
R}^n$.


title: A Time-Efficient Quantum Walk for 3-Distinctness Using Nested Updates

abstract:
  We present an extension to the quantum walk search framework that facilitates
quantum walks with nested updates. We apply it to give a quantum walk algorithm
for 3-Distinctness with query complexity ~O(n^{5/7}), matching the best known
upper bound (obtained via learning graphs) up to log factors. Furthermore, our
algorithm has time complexity ~O(n^{5/7}), improving the previous ~O(n^{3/4}).


title:
Weak phase stiffness and nature of the quantum critical point in
  underdoped cuprates

abstract:
  We demonstrate that the zero-temperature superconducting phase diagram of
underdoped cuprates can be quantitatively understood in the strong binding
limit, using only the experimental spectral function of the "normal" pseudo-gap
phase without any free parameter. In the prototypical
(La$_{1-x}$Sr$_x$)$_2$CuO$_4$, a kinetics-driven $d$-wave superconductivity is
obtained above the critical doping $\delta_c\sim 5.2\%$, below which complete
loss of superfluidity results from local quantum fluctuation involving local
$p$-wave pairs. Near the critical doping, a enormous mass enhancement of the
local pairs is found responsible for the observed rapid decrease of phase
stiffness. Finally, a striking mass divergence is predicted at $\delta_c$ that
dictates the occurrence of the observed quantum critical point and the abrupt
suppression of the Nernst effects in the nearby region.


title:
Accuracy of Homology based Coverage Hole Detection for Wireless Sensor
  Networks on Sphere

abstract:
  Homology theory has attracted great attention because it can provide novel
and powerful solutions to address coverage problems in wireless sensor
networks. They usually use an easily computable algebraic object, Rips complex,
to detect coverage holes. But Rips complex may miss some coverage holes in some
cases. In this paper, we investigate homology-based coverage hole detection for
wireless sensor networks on sphere. The situations when Rips complex may miss
coverage holes are first presented. Then we choose the proportion of the area
of coverage holes missed by Rips complex as a metric to evaluate the accuracy
of homology-based coverage hole detection approaches. Three different cases are
considered for the computation of accuracy. For each case, closed-form
expressions for lower and upper bounds of the accuracy are derived. Simulation
results are well consistent with the analytical lower and upper bounds, with
maximum differences of 0.5% and 3% respectively. Furthermore, it is shown that
the radius of sphere has little impact on the accuracy if it is much larger
than communication and sensing radii of each sensor.


title: On calculation of the interweight distribution of an equitable partition

abstract:
  We derive recursive and direct formulas for the interweight distribution of
an equitable partition of a hypercube. The formulas involve a three-variable
generalization of the Krawtchouk polynomials. Keywords: equitable partition;
regular partition; partition design; strong distance invariance; interweight
distribution; distance distribution; Krawtchouk polynomial


title:
Gain fractions of future neutrino oscillation facilities over T2K and
  NOvA

abstract:
  We evaluate the probability of future neutrino oscillation facilities to
discover leptonic CP violation and/or measure the neutrino mass hierarchy. We
study how this probability is affected by positive or negative hints for these
observables to be found at T2K and NOvA. We consider the following facilities:
LBNE; T2HK; and the 10 GeV Neutrino Factory (NF10), and show how their
discovery probabilities change with the running time of T2K and NOvA
conditioned to their results. We find that, if after 15 years T2K and NOvA have
not observed a 90% CL hint of CP violation, then LBNE and T2HK have less than a
10% chance of achieving a 5sigma discovery, whereas NF10 still has a ca 40%
chance to do so. Conversely, if T2K and NOvA have an early 90% CL hint in 5
years from now, T2HK has a rather large chance to achieve a 5sigma CP violation
discovery (75% or 55%, depending on whether the mass hierarchy is known or
not). This is to be compared with the 90% (30%) probability that NF10 (LBNE)
would have to observe the same signal at 5sigma. A hierarchy measurement at
5sigma is achievable at both LBNE and NF10 with more than 90% probability,
irrespectively of the outcome of T2K and NOvA. We also find that if LBNE or a
similar very long baseline super-beam is the only next generation facility to
be built, then it is very useful to continue running T2K and NOvA (or at least
T2K) beyond their original schedule in order to increase the CP violation
discovery chances, given their complementarity.


title: Constructions of transitive latin hypercubes

abstract:
  A function $f:\{0,...,q-1\}^n\to\{0,...,q-1\}$ invertible in each argument is
called a latin hypercube. A collection $(\pi_0,\pi_1,...,\pi_n)$ of
permutations of $\{0,...,q-1\}$ is called an autotopism of a latin hypercube
$f$ if $\pi_0f(x_1,...,x_n)=f(\pi_1x_1,...,\pi_n x_n)$ for all $x_1$, ...,
$x_n$. We call a latin hypercube isotopically transitive (topolinear) if its
group of autotopisms acts transitively (regularly) on all $q^n$ collections of
argument values. We prove that the number of nonequivalent topolinear latin
hypercubes grows exponentially with respect to $\sqrt{n}$ if $q$ is even and
exponentially with respect to $n^2$ if $q$ is divisible by a square. We show a
connection of the class of isotopically transitive latin squares with the class
of G-loops, known in noncommutative algebra, and establish the existence of a
topolinear latin square that is not a group isotope. We characterize the class
of isotopically transitive latin hypercubes of orders $q=4$ and $q=5$.
Keywords: transitive code, propelinear code, latin square, latin hypercube,
autotopism, G-loop.


title:
Energy conservation and gravity waves in sound-proof treatments of
  stellar interiors: Part II Lagrangian constrained analysis

abstract:
  The speed of sound greatly exceeds typical flow velocities in many stellar
and planetary interiors. To follow the slow evolution of subsonic motions,
various sound-proof models attempt to remove fast acoustic waves whilst
retaining stratified convection and buoyancy dynamics. In astrophysics,
anelastic models typically receive the most attention in the class of
sound-filtered stratified models. Generally, anelastic models remain valid in
nearly adiabatically stratified regions like stellar convection zones, but may
break down in strongly sub-adiabatic, stably stratified layers common in
stellar radiative zones. However, studying stellar rotation, circulation, and
dynamos requires understanding the complex coupling between convection and
radiative zones, and this requires robust equations valid in both regimes. Here
we extend the analysis of equation sets begun in Brown Vasil & Zweibel 2012,
which studied anelastic models, to two types of pseudo-incompressible models.
This class of models has received attention in atmospheric applications, and
more recently in studies of white-dwarf supernovae progenitors. We demonstrate
that one model conserves energy but the other does not. We use Lagrangian
variational methods to extend the energy conserving model to a general equation
of state, and dub the resulting equation set the Generalized
Pseudo-Incompressible (GPI) model. We show that the GPI equations suitably
capture low frequency phenomena in both convection and radiative zones in stars
and other stratified systems, and we provide recommendations for converting
low-Mach number codes to this equation set.

categories: astro-ph.SR astro-ph.EP physics.ao-ph physics.flu-dyn


title:
The Lyman alpha Reference Sample: Extended Lyman alpha Halos Produced at
  Low Dust Content

abstract:
  We report on new imaging observations of the Lyman alpha emission line (Lya),
performed with the Hubble Space Telescope, that comprise the backbone of the
Lyman alpha Reference Sample (LARS). We present images of 14 starburst galaxies
at redshifts 0.028 < z < 0.18 in continuum-subtracted Lya, Halpha, and the far
ultraviolet continuum. We show that Lya is emitted on scales that
systematically exceed those of the massive stellar population and recombination
nebulae: as measured by the Petrosian 20 percent radius, RP20, Lya radii are
larger than those of Halpha by factors ranging from 1 to 3.6, with an average
of 2.4. The average ratio of Lya-to-FUV radii is 2.9. This suggests that much
of the Lya light is pushed to large radii by resonance scattering. Defining the
"Relative Petrosian Extension" of Lya compared to Halpha, \xi_ext = RP20_Lya /
RP20_Ha, we find \xi_ext to be uncorrelated with total Lya luminosity. However
\xi_ext is strongly correlated with quantities that scale with dust content, in
the sense that a low dust abundance is a necessary requirement (although not
the only one) in order to spread Lya photons throughout the interstellar medium
and drive a large extended Lya halo.


title: Systematic simulations of modified gravity: chameleon models

abstract:
  In this work we systematically study the linear and nonlinear structure
formation in chameleon theories of modified gravity, using a generic
parameterisation which describes a large class of models using only 4
parameters. For this we have modified the N-body simulation code ECOSMOG to
perform a total of 65 simulations for different models and parameter values,
including the default LCDM. These simulations enable us to explore a
significant portion of the parameter space. We have studied the effects of
modified gravity on the matter power spectrum and mass function, and found a
rich and interesting phenomenology where the difference with the LCDM paradigm
cannot be reproduced by a linear analysis even on scales as large as
k~0.05h/Mpc, since the latter incorrectly assumes that the modification of
gravity depends only on the background matter density. Our results show that
the chameleon screening mechanism is significantly more efficient than other
mechanisms such as the dilaton and symmetron, especially in high-density
regions and at early times, and can serve as a guidance to determine the parts
of the chameleon parameter space which are cosmologically interesting and thus
merit further studies in the future.


title: Exploring Vainshtein mechanism on adaptively refined meshes

abstract:
  There has been a lot of research interest in modified gravity theories which
utilise the Vainshtein mechanism to recover standard general relativity in
regions with high matter density, such as the Dvali-Gabadadze-Porrati and
Galileon models. The strong nonlinearity in the field equations of these
theories implies that accurate theoretical predictions could only be made using
high-resolution cosmological simulations. Previously, such simulations were
usually done on regular meshes, which limits both their performance and the
accuracy. In this paper, we report the development of a new algorithm and code,
based on ECOSMOG, that uses adaptive mesh refinements to improve the efficiency
and precision in simulating the models with Vainshtein mechanism. We have made
various code tests against the numerical reliability, and found consistency
with previous simulations. We also studied the velocity field in the
self-accelerating branch of the DGP model. The code, parallelised using MPI, is
suitable for large cosmological simulations of Galileon-type modified gravity
theories.


title: Three AGN Close To The Effective Eddington Limit

abstract:
  The Effective Eddington Limit for dusty gas surrounding AGN is lower than the
canonical Eddington limit for hydrogen gas. Previous results from the Swift/BAT
9-month catalogue suggested that in the overwhelming majority of local AGN, the
dusty absorbing gas is below this Effective Eddington limit, implying that
radiation pressure is insufficient to blow away the absorbing clouds. We
present an analysis of three objects from that sample which were found to be
close to the Effective Eddington limit (NGC454, 2MASX J03565655-4041453 and XSS
J05054-2348), using newly obtained XMM-Newton data. We use the X-ray data to
better constrain the absorbing column density, and supplement them with XMM
optical monitor (OM) data, infrared Spitzer and Herschel data where available
to construct a broad-band spectral energy distribution to estimate refined
bolometric luminosities and Eddington ratios for these three objects. The new
XMM-Newton observations show all three objects moving away from the region
expected for short-lived absorption in the N_H-\lambda_{Edd} plane into the
`long-lived absorption' region. We find our conclusions robust to different
methods for estimating the bolometric luminosity and Eddington ratio.
Interestingly, 2MASX J03565655-4041453 and XSS J05054-2348 now exhibit complex
X-ray spectra, at variance with previous analyses of their Swift/XRT data. We
find evidence for absorption variability in NGC 454 and 2MASX
J03565655-4041453, perhaps implying that although the radiation pressure from
the central engine is insufficient to cause clearly detectable outflows, it may
cause absorption variations over longer timescales. However, more robust black
hole mass estimates would improve the accuracy of the Eddington ratio estimates
for these objects.


title: Segre classes of monomial schemes

abstract:
  We propose an explicit formula for the Segre classes of monomial subschemes
of nonsingular varieties, such as schemes defined by monomial ideals in
projective space. The Segre class is expressed as a formal integral on a region
bounded by the corresponding Newton polyhedron. We prove this formula for
monomial ideals in two variables and verify it for some families of examples in
any number of variables.


title:
Hard and soft bounds in the evolution of Ubuntu packages. A lesson for
  species body masses?

abstract:
  Open-source software is a complex system; its development depends on the
self-coordinated action of a large number of agents. This study follows the
size of the building blocks, called "packages", of the Ubuntu Linux operating
system over its entire history. The analysis reveals a multiplicative diffusion
process, constrained by size-dependent bounds, driving the dynamics of the
package-size distribution. A formalization of this into a quantitative model is
able to match the data without relying on any adjustable parameters, and
generates definite predictions. Finally, we formulate the hypothesis that a
similar non-stationary mechanism could be shaping the distribution of mammal
body sizes.


title: Magnetic vortex crystals in frustrated Mott insulator

abstract:
  Quantum fluctuations become particularly relevant in highly frustrated
quantum magnets and can lead to new states of matter. We provide a simple and
robust scenario for inducing magnetic vortex crystals in frustrated Mott
insulators. By considering a quantum paramagnet that has a gapped spectrum with
six-fold degenerate low energy modes, we study the magnetic field induced
condensation of these modes. We use a dilute gas approximation to demonstrate
that a plethora of multi-$\mathbf{Q}$ condensates are stabilized for different
combinations of exchange interactions. This rich quantum phase diagram includes
magnetic vortex crystals, which are further stabilized by symmetric exchange
anisotropies. Because magnetic skyrmion and domain wall crystals have already
been predicted and experimentally observed, this novel vortex phase completes
the picture of emergent crystals of topologically nontrivial spin
configurations.


title:
Cell-type-specific microarray data and the Allen atlas: quantitative
  analysis of brain-wide patterns of correlation and density

abstract:
  The Allen Atlas of the adult mouse brain is used to estimate the
region-specificity of 64 cell types whose transcriptional profile in the mouse
brain has been measured in microarray experiments. We systematically analyze
the preliminary results presented in [arXiv:1111.6217], using the techniques
implemented in the Brain Gene Expression Analysis toolbox. In particular, for
each cell-type-specific sample in the study, we compute a brain-wide
correlation profile to the Allen Atlas, and estimate a brain-wide density
profile by solving a quadratic optimization problem at each voxel in the mouse
brain. We characterize the neuroanatomical properties of the correlation and
density profiles by ranking the regions of the left hemisphere delineated in
the Allen Reference Atlas. We compare these rankings to prior biological
knowledge of the brain region from which the cell-type-specific sample was
extracted.


title: Complex geodesics in convex tube domains

abstract:
  We describe all complex geodesics in convex tube domains. In the case when
the base of a convex tube domain does not contain any real line, the obtained
description involves the notion of boundary measure of a holomorphic map and it
is expressed in the language of real Borel measures on the unit circle.
Applying our result, we calculate all complex geodesics in convex tube domains
with unbounded base covering special class of Reinhardt domains.


title:
Is the regime with shot noise suppression by a factor 1/3 achievable in
  semiconductor devices with mesoscopic dimensions?

abstract:
  We discuss the possibility of diffusive conduction and thus of suppression of
shot noise by a factor 1/3 in mesoscopic semiconductor devices with
two-dimensional and one-dimensional potential disorder, for which existing
experimental results do not provide a conclusive result. On the basis of our
numerical analysis, we conclude that it is quite difficult to achieve diffusive
transport over a reasonably wide parameter range, unless the device dimensions
are increased up to the macroscopic scale. In addition, in the case of
one-dimensional disorder, some mechanism capable of mode-mixing has to be
present in order to reach or even approach the diffusive regime.


title: Cardinality of Balls in Permutation Spaces

abstract:
  For a right invariant distance on a permutation space $S_n$ we give a
sufficient condition for the cardinality of a ball of radius $R$ to grow
polynomially in $n$ for fixed $R$. For the distance $\ell_1$ we show that for
an integer $k$ the cardinality of a sphere of radius $2k$ in $S_n$ (for $n
\geqslant k$) is a polynomial of degree $k$ in $n$ and determine the high
degree terms of this polynomial.


title:
Strong Convergence of Euler Approximations of Stochastic Differential
  Equations with Delay under Local Lipschitz Condition

abstract:
  The strong convergence of Euler approximations of stochastic delay
differential equations is proved under general conditions. The assumptions on
drift and diffusion coefficients have been relaxed to include polynomial growth
and only continuity in the arguments corresponding to delays. Furthermore, the
rate of convergence is obtained under one-sided and polynomial Lipschitz
conditions. Finally, our findings are demonstrated with the help of numerical
simulations.


title: Sparse Shape Reconstruction

abstract:
  This paper introduces a new shape-based image reconstruction technique
applicable to a large class of imaging problems formulated in a variational
sense. Given a collection of shape priors (a shape dictionary), we define our
problem as choosing the right elements and geometrically composing them through
basic set operations to characterize desired regions in the image. This
combinatorial problem can be relaxed and then solved using classical descent
methods. The main component of this relaxation is forming certain compactly
supported functions which we call "knolls", and reformulating the shape
representation as a basis expansion in terms of such functions. To select
suitable elements of the dictionary, our problem ultimately reduces to solving
a nonlinear program with sparsity constraints. We provide a new sparse
nonlinear reconstruction technique to approach this problem. The performance of
proposed technique is demonstrated with some standard imaging problems
including image segmentation, X-ray tomography and diffusive tomography.


title: AGN proximity zone fossils and the delayed recombination of metal lines

abstract:
  We model the time-dependent evolution of metal-enriched intergalactic and
circumgalactic gas exposed to the fluctuating radiation field from an active
galactic nucleus (AGN). We consider diffuse gas densities (n_H=10^-5-10^-3
cm^-3) exposed to the extra-galactic background (EGB) and initially in thermal
equilibrium (T \sim 10^4-10^4.5 K). Once the proximate AGN field turns on,
additional photo-ionisation rapidly ionises the HI and metals. The enhanced AGN
radiation field turns off after a typical AGN lifetime (tau_AGN=1-20 Myr) and
the field returns to the EGB intensity, but the metals remain out of ionisation
equilibrium for timescales that can significantly exceed tau_AGN. We define
this phase as the AGN proximity zone "fossil" phase and show that high
ionisation stages (e.g. OVI, NeVIII, MgX) are in general enhanced, while the
abundances of low ions are reduced. In contrast, HI re-equilibrates rapidly
(<<tau_AGN) owing to its low neutral fraction at diffuse densities. We
demonstrate that metal column densities of intervening gas observed in
absorption in quasar sight lines are significantly affected by delayed
recombination for a wide range of densities, metallicities, and AGN strengths,
lifetimes, and duty cycles. We model the exceptionally strong z=0.9 NeVIII
absorbers observed by Tripp et al. (2011) as arising in a possible fossil zone
or near a recently turned-on AGN and we demonstrate that at low redshift even
moderate strength AGN could significantly enhance the high-ion metal columns in
the circumgalactic media of galaxies observed without active AGN. Fossil
proximity zones may be very important during the quasar era, z \sim 2-5. AGN
proximity zone fossils allow a whole new class of non-equilibrium solutions
that may be applicable to a large fraction of observed metal absorbers and
which could potentially change the inferred physical conditions and masses of
diffuse gases.


title: A weak*-topological dichotomy with applications in operator theory

abstract:
  Denote by $[0,\omega_1)$ the locally compact Hausdorff space consisting of
all countable ordinals, equipped with the order topology, and let
$C_0[0,\omega_1)$ be the Banach space of scalar-valued, continuous functions
which are defined on $[0,\omega_1)$ and vanish eventually. We show that a
weakly$^*$ compact subset of the dual space of $C_0[0,\omega_1)$ is either
uniformly Eberlein compact, or it contains a homeomorphic copy of the ordinal
interval $[0,\omega_1]$.
  Using this result, we deduce that a Banach space which is a quotient of
$C_0[0,\omega_1)$ can either be embedded in a Hilbert-generated Banach space,
or it is isomorphic to the direct sum of $C_0[0,\omega_1)$ and a subspace of a
Hilbert-generated Banach space. Moreover, we obtain a list of eight equivalent
conditions describing the Loy-Willis ideal, which is the unique maximal ideal
of the Banach algebra of bounded, linear operators on $C_0[0,\omega_1)$. As a
consequence, we find that this ideal has a bounded left approximate identity,
thus resolving a problem left open by Loy and Willis, and we give new proofs,
in some cases of stronger versions, of several known results about the Banach
space $C_0[0,\omega_1)$ and the operators acting on it.


title: Two-qubit quantum gates for defect qubits in diamond and similar systems

abstract:
  We propose a fast, scalable all-optical design for arbitrary two-qubit
operations for defect qubits in diamond (NV centers) and in silicon carbide,
which are promising candidates for room temperature quantum computing. The
interaction between qubits is carried out by microcavity photons. The approach
uses constructive interference from higher energy excited states activated by
optical control. In this approach the cavity mode remains off-resonance with
the directly accessible optical transitions used for initialization and
readout. All quantum operations are controlled by near-resonant
narrow-bandwidth optical pulses. We perform full quantum numerical modeling of
the proposed gates and show that high-fidelity operations can be obtained with
realistic parameters.


title:
Status of nucleon structure calculations with 2+1 flavors of domain wall
  fermions

abstract:
  We report the status of our nucleon structure calculations with 2+1 flavors
of domain wall fermions on the RBC-UKQCD $32^3\times64$ gauge ensembles with
the Iwasaki+DSDR action. These ensembles have a fixed lattice scale of 1/a =
1.37 GeV, and two pion masses of about 170 and 250 MeV. Preliminary results for
the isovector electromagnectic form factors and their corresponding
root-mean-squared (r.m.s.) radii will be presented.


title: Enhancing Clustering Algorithm to Plan Efficient Mobile Network

abstract:
  With the rapid development in mobile network effective network planning tool
is needed to satisfy the need of customers. However, deciding upon the optimum
placement for the base stations (BS) to achieve best services while reducing
the cost is a complex task requiring vast computational resource. This paper
addresses antenna placement problem or the cell planning problem, involves
locating and configuring infrastructure for mobile networks. The Cluster
Partitioning Around Medoids (PAM) original algorithm has been modified and a
new algorithm M-PAM (Modified-Partitioning Around Medoids) has been proposed by
the authors in a recent work. In the present paper, the M-PAM algorithm is
modified and a new algorithm CWN-PAM (Clustering with Weighted
Node-Partitioning Around Medoids) has been proposed to satisfy the requirements
and constraints. Implementation of this algorithm to a real case study is
presented. Results demonstrate the effectiveness and flexibility of the
modifying algorithm in tackling the important problem of mobile network
planning.


title:
Physical Properties of Spectroscopically-Confirmed Galaxies at z >= 6.
  I. Basic Characteristics of the Rest-Frame UV Continuum and Lyman-alpha
  emission

abstract:
  We present deep HST near-IR and Spitzer mid-IR observations of a large sample
of spectroscopically-confirmed galaxies at z >= 6. The sample consists of 51
Lyman-alpha emitters (LAEs) at z ~ 5.7, 6.5, and 7.0, and 16 Lyman-break
galaxies (LBGs) at 5.9 < z < 6.5. The near-IR images were mostly obtained with
WFC3 in the F125W and F160W bands, and the mid-IR images were obtained with
IRAC in the 3.6um and 4.5um bands. Our galaxies also have deep optical imaging
data from Subaru Suprime-Cam. We utilize the multi-band data and secure
redshifts to derive their rest-frame UV properties. These galaxies have steep
UV continuum slopes roughly between beta ~ -1.5 and -3.5, with an average value
of beta ~ -2.3, slightly steeper than the slopes of LBGs in previous studies.
The slope shows little dependence on UV continuum luminosity except for a few
of the brightest galaxies. We find a statistically significant excess of
galaxies with slopes around beta ~ -3, suggesting the existence of very young
stellar populations with extremely low metallicity and dust content. Our
galaxies have moderately strong rest-frame Lyman-alpha equivalent width (EW) in
a range of ~10 to ~200 \AA. The star-formation rates are also moderate, from a
few to a few tens solar masses per year. The LAEs and LBGs in this sample share
many common properties, implying that LAEs represent a subset of LBGs with
strong Lyman-alpha emission. Finally, the comparison of the UV luminosity
functions between LAEs and LBGs suggests that there exists a substantial
population of faint galaxies with weak Lyman-alpha emission (EW < 20 \AA) that
could be the dominant contribution to the total ionizing flux at z >= 6.


title:
Search for the CP violating $K_S \to 3\pi^0$ decay with the KLOE
  detector

abstract:
  We present a new search for the $K_S \to 3\pi^0$ decay performed with the
KLOE detector operating at the DA$\Phi$NE $\phi$--factory. The $K_S$ mesons
were tagged via registration of $K_L$ mesons which crossed the drift chamber
without decaying and interacted with the KLOE electromagnetic calorimeter. The
$K_S \to 3\pi^0$ decay was then searched requiring six prompt photons. To
suppress background, originating from fake $K_S$ tags and $K_S \to 2\pi^0$
decays with additional two spurious clusters, we have performed a discriminant
analysis based on kinematical fit, testing of the signal and background
hypotheses and exploiting of the differences in kinematics of the $K_S$ decays
into $2\pi^0$ and $3\pi^0$. In a sample of about 1.7$\cdot 10^9$ $\phi \to K_S
K_L$ events we have found no candidates in data and simulated background
samples. Normalizing to the number of $K_S \to 2\pi^0$ events in the same
sample, we have set the upper limit on the $K_S \to 3\pi^0$ branching ratio
BR($K_S \to 3\pi^0) < 2.6 \cdot 10^{-8}$ at 90% C.L., five times lower than the
previous limit. This upper limit can be translated into a limit on the modulus
of the $\eta_{000}$ parameter amounting to $|\eta_{000}| < 0.0088$ at 90% C.L.,
improving by a factor two the latest direct measurement.


title: When Hamilton circuits generate the cycle space of a random graph

abstract:
  If eps > 0 and p >= n^{-1/2 + eps}, in a binomial random graph G(n,p) a.a.s.
the set of cycles which can be constructed as a symmetric difference of
Hamilton circuits is as large as parity by itself permits (all cycles if n is
odd, all even cycles if n is even). Moreover, every p which ensures the above
property a.a.s. must necessarily be such that for any constant c>0, eventually
p >= (log n + 2 log log n + c)/n. So, whatever the smallest sufficient p for an
a.a.s. Hamilton-generated cycle space might be, it does not coincide with the
threshold for hamiltonicity of G(n,p).


title:
Physical Properties of Spectroscopically-Confirmed Galaxies at z >= 6.
  II. Morphology of the Rest-Frame UV Continuum and Lyman-alpha Emission

abstract:
  We present a detailed structural and morphological study of a large sample of
spectroscopically-confirmed galaxies at z >= 6, using deep HST near-IR
broad-band images and Subaru optical narrow-band images. The galaxy sample
consists of 51 Lyman-alpha emitters (LAEs) at z ~ 5.7, 6.5, and 7.0, and 16
Lyman-break galaxies (LBGs) at 5.9 < z < 6.5. These galaxies exhibit a wide
range of rest-frame UV continuum morphology in the HST images, from compact
features to multiple component systems. The fraction of merging/interacting
galaxies reaches 40% ~ 50% at the brightest end of M_1500 <= -20.5 mag. The
intrinsic half-light radii r_{hl,in}, after correction for PSF broadening, are
roughly between r_{hl,in} ~ 0.05" (0.3 kpc) and 0.3" (1.7 kpc) at M_1500 <=
-19.5 mag. The median r_{hl,in} value is 0.16" (~0.9 kpc). This is consistent
with the sizes of bright LAEs and LBGs at z >= 6 in previous studies. In
addition, more luminous galaxies tend to have larger sizes, exhibiting a weak
size-luminosity relation r_{hl,in} \propto L^{0.14} at M_1500 <= -19.5 mag. The
slope of 0.14 is significantly flatter than those in fainter LBG samples. We
discuss the morphology of z >= 6 galaxies with nonparametric methods, including
the CAS system and the Gini and M_20 parameters, and demonstrate their validity
through simulations. We search for extended Lyman-alpha emission halos around
LAEs at z ~ 5.7 and 6.5, by stacking a number of narrow-band images. We do not
find evidence of extended halos predicted by cosmological simulations. Such
Lyman-alpha halos, if they exist, could be weaker than predicted. Finally, we
investigate any positional misalignment between UV continuum and Lyman-alpha
emission in LAEs. While the two positions are generally consistent, several
merging galaxies show significant positional differences. This is likely caused
by a disturbed ISM distribution due to merging activity.


title: The Einstein@Home search for radio pulsars and PSR J2007+2722 discovery

abstract:
  Einstein@Home aggregates the computer power of hundreds of thousands of
volunteers from 193 countries, to search for new neutron stars using data from
electromagnetic and gravitational-wave detectors. This paper presents a
detailed description of the search for new radio pulsars using Pulsar ALFA
survey data from the Arecibo Observatory. The enormous computing power allows
this search to cover a new region of parameter space; it can detect pulsars in
binary systems with orbital periods as short as 11 minutes. We also describe
the first Einstein@Home discovery, the 40.8 Hz isolated pulsar PSR J2007+2722,
and provide a full timing model. PSR J2007+2722's pulse profile is remarkably
wide with emission over almost the entire spin period. This neutron star is
most likely a disrupted recycled pulsar, about as old as its characteristic
spin-down age of 404 Myr. However there is a small chance that it was born
recently, with a low magnetic field. If so, upper limits on the X-ray flux
suggest but can not prove that PSR J2007+2722 is at least ~ 100 kyr old. In the
future, we expect that the massive computing power provided by volunteers
should enable many additional radio pulsar discoveries.


title: ELT-MOS White Paper: Science Overview & Requirements

abstract:
  The workhorse instruments of the 8-10m class observatories have become their
multi-object spectrographs (MOS), providing comprehensive follow-up to both
ground-based and space-borne imaging. With the advent of deeper imaging surveys
from, e.g., the HST and VISTA, there are a plethora of spectroscopic targets
which are already beyond the sensitivity limits of current facilities. This
wealth of targets will grow even more rapidly in the coming years, e.g., after
the completion of ALMA, the launch of the JWST and Euclid, and the advent of
the LSST. Thus, one of the key requirements underlying plans for the next
generation of ground-based telescopes, the Extremely Large Telescopes (ELTs),
is for even greater sensitivity for optical and infrared spectroscopy. Here we
revisit the scientific motivation for a MOS capability on the European ELT,
combining updated elements of science cases advanced from the Phase A
instrument studies with new science cases which draw on the latest results and
discoveries. These science cases address key questions related to galaxy
evolution over cosmic time, from studies of resolved stellar populations in
nearby galaxies out to observations of the most distant galaxies, and are used
to identify the top-level requirements on an 'E-ELT/MOS'. We argue that several
of the most compelling ELT science cases demand MOS observations, in highly
competitive areas of modern astronomy. Recent technical studies have
demonstrated that important issues related to e.g. sky subtraction and
multi-object AO can be solved, making fast- track development of a MOS
instrument feasible. To ensure that ESO retains world leadership in exploring
the most distant objects in the Universe, galaxy evolution and stellar
populations, we are convinced that a MOS should have high priority in the
instrumentation plan for the E-ELT.


title: Coupled skinny baker's maps and the Kaplan-Yorke conjecture

abstract:
  The Kaplan-Yorke conjecture states that for "typical" dynamical systems with
a physical measure, the information dimension and the Lyapunov dimension
coincide. We explore this conjecture in a neighborhood of a system for which
the two dimensions do not coincide because the system consists of two uncoupled
subsystems. We are interested in whether coupling "typically" restores the
equality of the dimensions. The particular subsystems we consider are skinny
baker's maps, and we consider uni-directional coupling. For coupling in one of
the possible directions, we prove that the dimensions coincide for a prevalent
set of coupling functions, but for coupling in the other direction we show that
the dimensions remain unequal for all coupling functions. We conjecture that
the dimensions prevalently coincide for bi-directional coupling. On the other
hand, we conjecture that the phenomenon we observe for a particular class of
systems with uni-directional coupling, where the information and Lyapunov
dimensions differ robustly, occurs more generally for many classes of
uni-directionally coupled systems (also called skew-product systems) in higher
dimensions.


title: Time Scales in Probabilistic Models of Wireless Sensor Networks

abstract:
  We consider a stochastic model of clock synchronization in a wireless network
consisting of N sensors interacting with one dedicated accurate time server.
For large N we find an estimate of the final time sychronization error for
global and relative synchronization. Main results concern a behavior of the
network on different time scales $t=t_N \to \infty$, $N \to \infty$. We discuss
existence of phase transitions and find exact time scales on which an effective
clock synchronization of the system takes place.


title:
Specificity, flexibility and valence of DNA bonds guide emulsion
  architecture

abstract:
  The specificity and thermal reversibility of DNA interactions have enabled
the self-assembly of crystal structures, self-replicating materials and
colloidal molecules. Grafting DNA onto liquid interfaces of emulsions leads to
exciting new architectural possibilities due to the mobility of the DNA ligands
and the patches they form between bound droplets. Here we show that the size
and number of these adhesion patches (valency) can be controlled. Valence 2
leads to flexible polymers of emulsion droplets, while valence above 4 leads to
rigid droplet networks. A simple thermodynamic model quantitatively describes
the increase in the patch size with droplet radii, DNA concentration and the
stiffness of the tether to the sticky-end. The patches are formed between
droplets with complementary DNA strands or alternatively with complementary
colloidal nanoparticles to mediate DNA binding between droplets. This emulsion
system opens the route to directed self-assembly of more complex structures
through distinct DNA bonds with varying strengths and controlled valence and
flexibility.


title: Role of Van der Waals forces in graphene adsorption over Pd, Pt and Ni

abstract:
  We report ab initiocomputations with the Vienna ab Initio Simulation Package
(VASP) aimed at elucidating the adsorption mechanism of graphene-like
structures on (111) Pd, Pt, and Ni surfaces. To study the adsorption
properties, we simulate an already-formed graphene layer. We present a
comparative discussion of the graphene interactions with the three metals,
focusing on the very particular adsorption of graphene over Pd.


title: A Black Hole Nova Obscured by an Inner Disk Torus

abstract:
  Stellar-mass black holes (BHs) are mostly found in X-ray transients, a
subclass of X-ray binaries that exhibit violent outbursts. None of the 50
Galactic BHs known show eclipses, which is surprising for a random distribution
of inclinations. Swift J1357.2-0933 is a very faint X-ray transient detected in
2011. On the basis of spectroscopic evidence, we show that it contains a BH in
a 2.8 h orbital period. Further, high-time resolution optical light curves
display profound dips without X-ray counterparts. The observed properties are
best explained by the presence of an obscuring toroidal structure moving
outwards in the inner disk seen at very high inclination. This observational
feature should play a key role in models of inner accretion flows and jet
collimation mechanisms in stellar-mass BHs.


title:
An $O^*(1.1939^n)$ time algorithm for minimum weighted dominating
  induced matching

abstract:
  Say that an edge of a graph $G$ dominates itself and every other edge
adjacent to it. An edge dominating set of a graph $G=(V,E)$ is a subset of
edges $E' \subseteq E$ which dominates all edges of $G$. In particular, if
every edge of $G$ is dominated by exactly one edge of $E'$ then $E'$ is a
dominating induced matching. It is known that not every graph admits a
dominating induced matching, while the problem to decide if it does admit it is
NP-complete. In this paper we consider the problems of finding a minimum
weighted dominating induced matching, if any, and counting the number of
dominating induced matchings of a graph with weighted edges. We describe an
exact algorithm for general graphs that runs in $O^*(1.1939^n)$ time and
polynomial (linear) space. This improves over any existing exact algorithm for
the problems in consideration.


title:
The merger fraction of active and inactive galaxies in the local
  Universe through an improved non-parametric classification

abstract:
  We investigate the possible link between mergers and the enhanced activity of
supermassive black holes (SMBHs) at the centre of galaxies, by comparing the
merger fraction of a local sample (0.003 =< z < 0.03) of active galaxies - 59
active galactic nuclei (AGN) host galaxies selected from the all-sky Swift BAT
(Burst Alert Telescope) survey - with an appropriate control sample (247
sources extracted from the Hyperleda catalogue) that has the same redshift
distribution as the BAT sample. We detect the interacting systems in the two
samples on the basis of non-parametric structural indexes of concentration (C),
asymmetry (A), clumpiness (S), Gini coefficient (G) and second order momentum
of light (M20). In particular, we propose a new morphological criterion, based
on a combination of all these indexes, that improves the identification of
interacting systems. We also present a new software - PyCASSo (Python CAS
Software) - for the automatic computation of the structural indexes. After
correcting for the completeness and reliability of the method, we find that the
fraction of interacting galaxies among the active population, 20(+7/-5) per
cent, exceeds the merger fraction of the control sample, 4(+1.7/-1.2) per cent.
Choosing a mass-matched control sample leads to equivalent results, although
with slightly lower statistical significance. Our findings support the scenario
in which mergers trigger the nuclear activity of supermassive black holes.


title:
Multiple light scattering on the F = 1 - F' = 0 transition in a cold and
  high density 87Rb vapor

abstract:
  We report an experimental study of near resonance light scattering on the $F
= 1 \rightarrow F' = 0$ component of the $D_2$ line in atomic $^{87}Rb$.
Experiments are performed on spatially bi-Gaussian ultracold gas samples having
peak densities ranging from about $5 \cdot 10^{12} - 5 \cdot 10^{13}$
atoms/cm$^{3}$ and for a range of resonance saturation parameters and detunings
from atomic resonance. Time resolution of the scattered light intensity reveals
dynamics of multiple light scattering, optical pumping, and saturation effects.
The experimental results in steady-state are compared qualitatively with
theoretical models of the light scattering process. The steady-state line shape
of the excitation spectrum is in good qualitative agreement with these models.


title: Approximately Optimal Scheduling of an M/G/1 Queue with Heavy Tails

abstract:
  Distributions with a heavy tail are difficult to estimate. If the design of a
scheduling policy is sensitive to the details of heavy tail distributions of
the service times, an approximately optimal solution is difficult to obtain.
This paper shows that the optimal scheduling of an M/G/1 queue with heavy
tailed service times does not present this difficulty and that an approximately
optimal strategy can be derived by truncating the distributions.


title:
Atomistic Boron-Doped Graphene Field Effect Transistors: A Route towards
  Unipolar Characteristics

abstract:
  We report fully quantum simulations of realistic models of boron-doped
graphene-based field effect transistors, including atomistic details based on
DFT calculations. We show that the self-consistent solution of the
three-dimensional (3D) Poisson and Schr\"odinger equations with a
representation in terms of a tight-binding Hamiltonian manages to accurately
reproduce the DFT results for an isolated boron-doped graphene nanoribbon.
Using a 3D Poisson/Schr\"odinger solver within the Non-Equilibrium Green's
Functions (NEGF) formalism, self-consistent calculations of the gate-screened
scattering potentials induced by the boron impurities have been performed,
allowing the theoretical exploration of the tunability of transistor
characteristics. The boron-doped graphene transistors are found to approach
unipolar behavior as the boron concentration is increased, and by tuning the
density of chemical dopants the electron-hole transport asymmetry can be finely
adjusted. Correspondingly, the onset of a mobility gap in the device is
observed. Although the computed asymmetries are not sufficient to warrant
proper device operation, our results represent an initial step in the direction
of improved transfer characteristics and, in particular, the developed
simulation strategy is a powerful new tool for modeling doped graphene
nanostructures.


title: Temperature Effects on Brain Tissue in Compression

abstract:
  Extensive research has been carried out for at least 50 years to understand
the mechanical properties of brain tissue in order to understand the mechanisms
of traumatic brain injury (TBI). The observed large variability in experimental
results may be due to the inhomogeneous nature of brain tissue and to the broad
range of test conditions. However, test temperature is also considered as one
of the factors influencing the properties of brain tissue. In this research,
the mechanical properties of porcine brain have been investigated at 22C (room
temperature) and at 37C (body temperature) while maintaining a constant
preservation temperature of approximately 4-5C. Unconfined compression tests
were performed at dynamic strain rates of 30 and 50/s using a custom made test
apparatus. There was no significant difference (p = 0.8559 - 0.9290) between
the average engineering stresses of the brain tissue at the two different
temperature conditions. The results of this study should help to understand the
behavior of brain tissue at different temperature conditions, particularly in
unconfined compression tests.


title: QCSP on partially reflexive cycles - the wavy line of tractability

abstract:
  We study the (non-uniform) quantified constraint satisfaction problem QCSP(H)
as H ranges over partially reflexive cycles. We obtain a complexity-theoretic
dichotomy: QCSP(H) is either in NL or is NP-hard. The separating conditions are
somewhat esoteric hence the epithet "wavy line of tractability".


title:
Twelve Years of Education and Public Outreach with the Fermi Gamma-ray
  Space Telescope

abstract:
  During the past twelve years, NASA's Fermi Gamma-ray Space Telescope has
supported a wide range of Education and Public Outreach (E/PO) activities,
targeting K-14 students and the general public. The purpose of the Fermi E/PO
program is to increase student and public understanding of the science of the
high-energy Universe, through inspiring, engaging and educational activities
linked to the mission's science objectives. The E/PO program has additional
more general goals, including increasing the diversity of students in the
Science, Technology, Engineering and Mathematics (STEM) pipeline, and
increasing public awareness and understanding of Fermi science and technology.
Fermi's multi-faceted E/PO program includes elements in each major outcome
category: Higher Education; Elementary and Secondary Education; Informal
Education and Public Outreach.


title:
Quasar Absorption Lines in the Far Ultraviolet: An Untapped Gold Mine
  for Galaxy Evolution Studies

abstract:
  This white paper emphasizes the potential of QSO absorption lines in the
rest-frame far/extreme UV at rest-frame wavelengths from ~500 to 2000 A. In
this wavelength range, species such as Ne VIII, Na IX, and Mg X can be
detected, providing diagnostics of gas with temperatures >> 10^{6} K, as well
as banks of adjacent ions such as O I, O II, O III, O IV, O V, and O VI (and
similarly N I - N V; S II - S VI; Ne II - Ne VIII, etc.), which constrain
physical conditions with unprecedented precision. A UV spectrograph with good
sensitivity down to observed wavelengths of 1000 A can detect these new probes
in absorption systems with redshift z(abs) > 0.3, and at these redshifts, the
detailed relationships between the absorbers and nearby galaxies and
large-scale environment can be studied from the ground. By observing QSOs at z
= 1.0 - 1.5, HST has started to exploit extreme-UV QSO absorption lines, but
HST can only reach a small number of these targets. A future, more sensitive UV
spectrograph could open up this new discovery space.


title: A connection between concurrency and language theory

abstract:
  We show that three fixed point structures equipped with (sequential)
composition, a sum operation, and a fixed point operation share the same valid
equations. These are the theories of (context-free) languages, (regular) tree
languages, and simulation equivalence classes of (regular) synchronization
trees (or processes). The results reveal a close relationship between classical
language theory and process algebra.


title: The Mesh of Civilizations and International Email Flows

abstract:
  In The Clash of Civilizations, Samuel Huntington argued that the primary axis
of global conflict was no longer ideological or economic but cultural and
religious, and that this division would characterize the "battle lines of the
future." In contrast to the "top down" approach in previous research focused on
the relations among nation states, we focused on the flows of interpersonal
communication as a bottom-up view of international alignments. To that end, we
mapped the locations of the world's countries in global email networks to see
if we could detect cultural fault lines. Using IP-geolocation on a worldwide
anonymized dataset obtained from a large Internet company, we constructed a
global email network. In computing email flows we employ a novel rescaling
procedure to account for differences due to uneven adoption of a particular
Internet service across the world. Our analysis shows that email flows are
consistent with Huntington's thesis. In addition to location in Huntington's
"civilizations," our results also attest to the importance of both cultural and
economic factors in the patterning of inter-country communication ties.


title: Inhomogeneous Deformation of Brain Tissue During Tension Tests

abstract:
  Mechanical characterization of brain tissue has been investigated extensively
by various research groups over the past fifty years. These properties are
particularly important for modelling Traumatic Brain Injury (TBI). In this
research, we present the design and calibration of a High Rate Tension Device
(HRTD) capable of performing tests up to a maximum strain rate of 90/s. We use
experimental and numerical methods to investigate the effects of inhomogeneous
deformation of porcine brain tissue during tension at different specimen
thicknesses (4.0-14.0 mm), by performing tension tests at a strain rate of
30/s. One-term Ogden material parameters (mu = 4395.0 Pa, alpha = -2.8) were
derived by performing an inverse finite element analysis to model all
experimental data. A similar procedure was adopted to determine Young's modulus
(E= 11200 Pa) of the linear elastic regime. Based on this analysis, brain
specimens of aspect ratio (diameter/thickness) S < 1.0 are required to minimise
the effects of inhomogeneous deformation during tension tests.


title:
Gauged baryon and lepton numbers in supersymmetry with a $125\;{\rm
  GeV}$ Higgs

abstract:
  Assuming that the Yukawa couplings between the Higgs and exotic quarks cannot
be ignored, we analyze the signals of decay channels $h\rightarrow\gamma\gamma$
and $h\rightarrow VV^*\;(V=Z,\;W)$ with the Higgs mass around $125\;{\rm GeV}$
in a supersymmetric extension of the standard model where baryon and lepton
numbers are local gauge symmetries. Adopting some assumptions on relevant
parameter space, we can account for the experimental data on Higgs from ATLAS
and CMS naturally.


title:
Determination of Friction Coefficient in Unconfined Compression of Brain
  Tissue

abstract:
  Unconfined compression tests are more convenient to perform on cylindrical
samples of brain tissue than tensile tests in order to estimate mechanical
properties of the brain tissue because they allow for homogeneous deformations.
The reliability of these tests depends significantly on the amount of friction
generated at the specimen/platen interface. Thus, there is a crucial need to
find an approximate value of the friction coefficient in order to predict a
possible overestimation of stresses during unconfined compression tests. In
this study, a combined experimental-computational approach was adopted to
estimate the dynamic friction coefficient mu of porcine brain matter against
metal platens in compressive tests. Cylindrical samples of porcine brain tissue
were tested up to 30% strain at variable strain rates, both under bonded and
lubricated conditions in the same controlled environment. It was established
that mu was equal to 0.09 +/- 0.03, 0.18 +/- 0.04, 0.18 +/- 0.04 and 0.20 +/-
0.02 at strain rates of 1, 30, 60 and 90/s, respectively. Additional tests were
also performed to analyze brain tissue under lubricated and bonded conditions,
with and without initial contact of the top platen with the brain tissue, with
different specimen aspect ratios and with different lubricants (Phosphate
Buffer Saline (PBS), Polytetrafluoroethylene (PTFE) and Silicon). The test
conditions (lubricant used, biological tissue, loading velocity) adopted in
this study were similar to the studies conducted by other research groups. This
study will help to understand the amount of friction generated during
unconfined compression of brain tissue for strain rates of up to 90/s.


title: Equivalent Neutrinos, Light WIMPs, and the Chimera of Dark Radiation

abstract:
  According to conventional wisdom, in the standard model (SM) of particle
physics and cosmology the effective number of neutrinos is Neff=3 (more
precisely, 3.046). In extensions of the standard model allowing for the
presence of DeltaNnu equivalent neutrinos (or dark radiation), Neff is
generally >3. The canonical results are reconsidered here, revealing that a
measurement of Neff>3 can be consistent with DeltaNnu=0 (dark radiation without
dark radiation). Conversely, a measurement consistent with Neff=3 is not
inconsistent with the presence of dark radiation (DeltaNnu>0). In particular,
if there is a light WIMP that annihilates to photons after the SM neutrinos
have decoupled, the photons are heated beyond their usual heating from e+-
annihilation, reducing the late time ratio of neutrino and photon temperatures
(and number densities), leading to Neff<3. This opens the window for one or
more equivalent neutrinos, including sterile neutrinos, to be consistent with
Neff=3. By reducing the neutrino number density at present, this allows for
more massive neutrinos, relaxing the current constraints on the sum of the
neutrino masses. In contrast, if the light WIMP only couples to the SM
neutrinos and not to the photons, its late time annihilation heats the
neutrinos but not the photons, resulting in Neff>3 even in the absence of
equivalent neutrinos or dark radiation. A measurement of Neff>3 is thus no
guarantee of the presence of equivalent neutrinos or dark radiation. In the
presence of light WIMPs and/or equivalent neutrinos there are degeneracies
among the light WIMP mass and its nature (fermion or boson, as well as its
couplings to neutrinos or photons), the number and nature (fermion or boson) of
the equivalent neutrinos, and their decoupling temperature (the strength of
their interactions with the SM particles). There's more to a measurement of
Neff than meets the eye.


title:
Tracking the Empirical Distribution of a Markov-modulated
  Duplication-Deletion Random Graph

abstract:
  This paper considers a Markov-modulated duplication-deletion random graph
where at each time instant, one node can either join or leave the network; the
probabilities of joining or leaving evolve according to the realization of a
finite state Markov chain. The paper comprises of 2 results. First, motivated
by social network applications, we analyze the asymptotic behavior of the
degree distribution of the Markov-modulated random graph. Using the asymptotic
degree distribution, an expression is obtained for the delay in searching such
graphs. Second, a stochastic approximation algorithm is presented to track
empirical degree distribution as it evolves over time. The tracking performance
of the algorithm is analyzed in terms of mean square error and a functional
central limit theorem is presented for the asymptotic tracking error.


title:
On the exponential decay of Laplacian eigenfunctions in planar domains
  with branches

abstract:
  We consider the eigenvalue problem for the Laplace operator in a planar
domain which can be decomposed into a bounded domain of arbitrary shape and
elongated \branches" of variable cross-sectional profiles. When the eigenvalue
is smaller than a prescribed threshold, the corresponding eigenfunction decays
exponentially along each branch. We prove this behavior for Robin boundary
condition and illustrate some related results by numerically computed
eigenfunctions.


title: Identification of Background False Positives from Kepler Data

abstract:
  The Kepler Mission was launched on March 6, 2009 to perform a photometric
survey of more than 100,000 dwarf stars to search for Earth-size planets with
the transit technique. The reliability of the resulting planetary candidate
list relies on the ability to identify and remove false positives. Major
sources of astrophysical false positives are planetary transits and stellar
eclipses on background stars. We describe several new techniques for the
identification of background transit sources that are separated from their
target stars, indicating an astrophysical false positive. These techniques use
only Kepler photometric data. We describe the concepts and construction of
these techniques in detail as well as their performance and relative merits.


title:
The solution of the complete nontrivial cycle intersection problem for
  permutations

abstract:
  We prove the Complete nontrivial cycle-intersection theorem for systems of
permutations.


title: Correlation Inequality for Formal Series

abstract: We prove two correlation inequalities .


title:
Operator Quantum Zeno Effect: Protecting Quantum Information with Noisy
  Two-Qubit Interactions

abstract:
  The time evolution of some quantum states can be slowed down or even stopped
under frequent measurements. This is the usual quantum Zeno effect. Here, we
report an operator quantum Zeno effect, in which the evolution of some physical
observables is slowed down through measurements even though the quantum state
changes randomly with time. Based on the operator quantum Zeno effect, we show
how we can protect quantum information from decoherence with two-qubit
measurements, realizable with noisy two-qubit interactions.


title:
Deterministic photonic spatial-polarization hyper-controlled-not gate
  assisted by quantum dot inside one-side optical microcavity

abstract:
  Up to now, all the works about constructing quantum logic gates, an essential
part in quantum computing, are focused on operating on one degree of freedom
(DOF) of quantum systems. Here, we investigate the possibility to achieve a
scalable photonic quantum computing based on two DOFs of quantum systems and
construct a deterministic hyper-controlled-not (hyper-CNOT) gate operating on
both spatial-mode and polarization DOFs of a photon pair simultaneously, by
using the giant optical Faraday rotation induced by a single-electron spin in a
quantum dot inside a one-side optical microcavity as a result of cavity quantum
electrodynamics. With this hyper-CNOT gate and linear optical elements,
two-photon four-qubit cluster entangled states can be prepared and analyzed,
which gives an application to manipulate more information with less resources.
We analyze the experimental feasibility of this hyper-CNOT gate and show that
it can be implemented with current technology.


title:
Musielak-Orlicz-Hardy Spaces Associated with Operators Satisfying
  Reinforced Off-Diagonal Estimates

abstract:
  Let $\mathcal{X}$ be a metric space with doubling measure and $L$ a
one-to-one operator of type $\omega$ having a bounded $H_\infty$-functional
calculus in $L^2(\mathcal{X})$ satisfying the reinforced $(p_L, q_L)$
off-diagonal estimates on balls, where $p_L\in[1,2)$ and $q_L\in(2,\infty]$.
Let $\varphi:\,\mathcal{X}\times[0,\infty)\to[0,\infty)$ be a function such
that $\varphi(x,\cdot)$ is an Orlicz function, $\varphi(\cdot,t)\in {\mathbb
A}_{\infty}(\mathcal{X})$ (the class of uniformly Muckenhoupt weights), its
uniformly critical upper type index $I(\varphi)\in(0,1]$ and $\varphi(\cdot,t)$
satisfies the uniformly reverse H\"older inequality of order
$(q_L/I(\varphi))'$. In this paper, the authors introduce a
Musielak-Orlicz-Hardy space $H_{\varphi,\,L}(\mathcal{X})$, via the Lusin-area
function associated with $L$, and establish its molecular characterization. In
particular, when $L$ is nonnegative self-adjoint and satisfies the
Davies-Gaffney estimates, the atomic characterization of
$H_{\varphi,\,L}(\mathcal{X})$ is also obtained. Furthermore, a sufficient
condition for the equivalence between $H_{\varphi,\,L}(\mathbb{R}^n)$ and the
classical Musielak-Orlicz-Hardy space $H_{\varphi}(\mathbb{R}^n)$ is given.
Moreover, for the Musielak-Orlicz-Hardy space $H_{\varphi,\,L}(\mathbb{R}^n)$
associated with the second order elliptic operator in divergence form on $\rn$
or the Schr\"odinger operator $L:=-\Delta+V$ with $0\le V\in
L^1_{\mathrm{loc}}(\mathbb{R}^n)$, the authors further obtain its several
equivalent characterizations in terms of various non-tangential and radial
maximal functions; finally, the authors discuss the boundedness of the Riesz
transform $\nabla L^{-1/2}$.


title:
A Cooperative MARC Scheme Using Analogue Network Coding to Achieve
  Second-Order Diversity

abstract:
  A multiple access relay channel (MARC) is considered in which an
analogue-like network coding is implemented in the relay node. This analogue
coding is a simple addition of the received signals at the relay node. Using
"nulling detection" structure employed in V-BLAST receiver, we propose a
detection scheme in the destination which is able to provide a diversity order
of two for all users. We analytically evaluate the performance of our proposed
scheme for the MARC with two users where tight upper bounds for both uncoded
and Convolutionally coded transmission blocks are provided. We verify our
analytical evaluations by simulations and compare the results with those of
noncooperative transmission and Alamouti's scheme for the same power and rate
transmission. Our results indicate that while our proposed scheme shows a
comparable performance compared to the Alamouti's scheme, it substantially
outperforms the non-cooperate transmission.