title:
Cytoplasmic nanojunctions between lysosomes and sarcoplasmic reticulum
  are required for specific calcium signaling

abstract:
  We demonstrate how nanojunctions between lysosomes and sarcoplasmic reticulum
(L-SR junctions) serve to couple lysosomal activation to regenerative,
ryanodine receptor-mediated cellular calcium (Ca2+) waves. In pulmonary artery
smooth muscle cells (PASMCs) nicotinic acid adenine dinucleotide phosphate
(NAADP) may trigger increases in cytoplasmic Ca2+ via L-SR junctions, in a
manner that requires initial Ca2+ release from lysosomes and subsequent
Ca2+-induced Ca2+ release (CICR) via ryanodine receptor (RyR) subtype 3 on the
SR membrane proximal to lysosomes. L-SR junction membrane separation has been
estimated to be <400 nm and thus beyond the resolution of light microscopy.
This study utilizes transmission electron microscopy to provide a thorough
ultrastructural characterization of the L-SR junctions in PASMCs. These
junctions are prominent features in these cells and we estimate that the
membrane separation and extension are about 15 nm and 300 nm, respectively. We
also develop a quantitative model of the L-SR junction using these
measurements, prior kinetic and specific Ca2+ signal information as input data.
Simulations of NAADP-dependent junctional Ca2+ transients show that the
magnitude of these signals can breach the threshold for CICR via RyR3. By
correlation analysis of live cell Ca2+ signals and simulated L-SR junctional
Ca2+ transients, we estimate that "trigger zones" with a 60-100 junctions are
required to confer a signal of similar magnitude. This is compatible with the
130 lysosomes/cell estimated from our ultrastructural observations. Most
importantly, our model shows that increasing the L-SR junctional width above 50
nm lowers the magnitude of junctional [Ca2+] such that there is a failure to
breach the threshold for CICR via RyR3. L-SR junctions are therefore a
pre-requisite for efficient Ca2+ signal coupling and may contribute to cellular
function in health and disease.


title: On the 3-D structure and dissipation of reconnection-driven flow-bursts

abstract:
  The structure of magnetic reconnection-driven outflows and their dissipation
are explored with large-scale, 3-D particle-in-cell (PIC) simulations. Outflow
jets resulting from 3-D reconnection with a finite length x-line form fronts as
they propagate into the downstream medium. A large pressure increase ahead of
this ``reconnection jet front'' (RJF), due to reflected and transmitted ions,
slows the front so that its velocity is well below the velocity of the ambient
ions in the core of the jet. As a result, the RJF slows and diverts the
high-speed flow into the direction perpendicular to the reconnection plane. The
consequence is that the RJF acts as a thermalization site for the ion bulk flow
and contributes significantly to the dissipation of magnetic energy during
reconnection even though the outflow jet is subsonic. This behavior has no
counterpart in 2-D reconnection. A simple analytic model predicts the front
velocity and the fraction of the ion bulk flow energy that is dissipated.


title: Radiation pressure on a dielectric wedge

abstract:
  The force of electromagnetic radiation on a dielectric medium may be derived
by a direct application of the Lorentz law of classical electrodynamics. While
the light's electric field acts upon the (induced) bound charges in the medium,
its magnetic field exerts a force on the bound currents. We use the example of
a wedge-shaped solid dielectric, immersed in a transparent liquid and
illuminated at Brewster's angle, to demonstrate that the linear momentum of the
electromagnetic field within dielectrics has neither the Minkowski nor the
Abraham form; rather, the correct expression for momentum density has equal
contributions from both. The time rate of change of the incident momentum thus
expressed is equal to the force exerted on the wedge plus that experienced by
the surrounding liquid.


title:
Markovian versus non-Markovian stochastic quantization of a
  complex-action model

abstract:
  We analyze the Markovian and non-Markovian stochastic quantization methods
for a complex action quantum mechanical model analog to a Maxwell-Chern-Simons
eletrodynamics in Weyl gauge. We show through analytical methods convergence to
the correct equilibrium state for both methods. Introduction of a memory kernel
generates a non-Markovian process which has the effect of slowing down
oscillations that arise in the Langevin-time evolution toward equilibrium of
complex action problems. This feature of non-Markovian stochastic quantization
might be beneficial in large scale numerical simulations of complex action
field theories on a lattice.


title: Positive semigroups and abstract Lyapunov equations

abstract:
  We consider abstract equations of the form Ax=-z on a locally convex space,
where A generates a positive semigroup and z is a positive element. This is an
abstract version of the operator Lyapunov equation A*P+PA=-Q from control
theory. It is proved that under suitable assumptions existence of a positive
solution implies that -A has a positive inverse, and the generated semigroup is
asymptotically stable. We do not require that z is an order unit, or that the
space contains any order units. As an application, we generalize Wonham's
theorem on the operator Lyapunov equations with detectable right hand sides to
reflexive Banach spaces.


title:
Local Existence Theory for Derivative Nonlinear Schr\"{o}dinger
  Equations with Non-Integer Power Nonlinearities

abstract:
  We study a derivative nonlinear Schr\"{o}dinger equation, allowing
non-integer powers in the nonlinearity, $|u|^{2\sigma} u_x$. Making careful use
of the energy method, we are able to establish short-time existence of
solutions with initial data in the energy space, $H^1$. For more regular
initial data, we establish not just existence of solutions, but also
well-posedness of the initial value problem. These results hold for real-valued
$\sigma\geq 1,$ while prior existence results in the literature require
integer-valued $\sigma$ or $\sigma$ sufficiently large ($\sigma \geq 5/2$), or
use higher-regularity function spaces.


title:
Investigation of the Young's modulus and thermal expansion of amorphous
  titania-doped tantala films

abstract:
  The current generation of advanced gravitational wave detectors utilize
titania-doped tantala/silica multilayer stacks for their mirror coatings. The
properties of the low-refractive-index silica are well known; however, in the
absence of detailed direct measurements, the material parameters of Young's
modulus and coefficient of thermal expansion (CTE) of the high refractive index
material, titania-doped tantala, have been assumed to be equal to values
measured for pure tantala coatings. In order to ascertain the true values
necessary for thermal noise calculations, we have undertaken measurements of
Young's modulus and CTE through the use of nanoindentation and thermal-bending
measurements. The measurements were designed to assess the effects of titania
doping concentration and post-deposition heat-treatment on the measured values
in order to evaluate the possibility of optimizing material parameters to
further improve thermal noise in the detector. Young's modulus measurements on
pure tantala and 25% and 55% titania-doped tantala show a wide range of values,
from 132 to 177 GPa, dependent on both titania concentration and
heat-treatment. Measurements of CTE give values of (3.9 +/- 0.1) x 10^-6 K^-1
and (4.9 +/- 0.3) x 10^-6 K^-1 for 25% and 55% titania-doped tantala,
respectively, without dependence on post-deposition heat-treatment.


title:
Relaxation Patterns in Supercooled Liquids from Generalized
  Mode-Coupling Theory

abstract:
  The mode-coupling theory of the glass transition treats the dynamics of
supercooled liquids in terms of two-point density correlation functions. Here
we consider a generalized, hierarchical formulation of schematic mode-coupling
equations in which the full basis of multipoint density correlations is taken
into account. By varying the parameters that control the effective
contributions of higher-order correlations, we show that infinite hierarchies
can give rise to both sharp and avoided glass transitions. Moreover, small
changes in the form of the coefficients result in different scaling behaviors
of the structural relaxation time, providing a means to tune the fragility in
glass-forming materials. This demonstrates that the infinite-order construct of
generalized mode-coupling theory constitutes a powerful and unifying framework
for kinetic theories of the glass transition.


title: Gravitational anomalies signaling the breakdown of classical gravity

abstract:
  Recent observations for three types of astrophysical systems severely
challenge the GR plus dark matter scenario, showing a phenomenology which is
what modified gravity theories predict. Stellar kinematics in the outskirts of
globular clusters show the appearance of MOND type dynamics on crossing the
$a_{0}$ threshold. Analysis shows a ``Tully-Fisher'' relation in these systems,
a scaling of dispersion velocities with the fourth root of their masses.
Secondly, an anomaly has been found at the unexpected scales of wide binaries
in the solar neighbourhood. Binary orbital velocities cease to fall along
Keplerian expectations, and settle at a constant value, exactly on crossing the
$a_{0}$ threshold. Finally, the inferred infall velocity of the bullet cluster
is inconsistent with the standard cosmological scenario, where much smaller
limit encounter velocities appear. This stems from the escape velocity limit
present in standard gravity; the ``bullet'' should not hit the ``target'' at
more than the escape velocity of the joint system, as it very clearly did.
These results are consistent with extended gravity, but would require rather
contrived explanations under GR, each. Thus, observations now put us in a
situation where modifications to gravity at low acceleration scales cease to be
a matter of choice, to now become inevitable.


title: Connecting deterministic and stochastic metapopulation models

abstract:
  In this paper, we study the relationship between certain stochastic and
deterministic versions of Hanski's incidence function model and the spatially
realistic Levins model. We show that the stochastic version can be well
approximated in a certain sense by the deterministic version when the number of
habitat patches is large, provided that the presence or absence of individuals
in a given patch is influenced by a large number of other patches. Explicit
bounds on the deviation between the stochastic and deterministic models are
given.


title: Mixed f-divergence and inequalities for log concave functions

abstract:
  Mixed $f$-divergences, a concept from information theory and statistics,
measure the difference between multiple pairs of distributions. We introduce
them for log concave functions and establish some of their properties. Among
them are affine invariant vector entropy inequalities, like new
Alexandrov-Fenchel type inequalities and an affine isoperimetric inequality for
the vector form of the Kullback Leibler divergence for log concave functions.
Special cases of $f$-divergences are mixed $L_\lambda$-affine surface areas for
log concave functions. For those, we establish various affine isoperimetric
inequalities as well as a vector Blaschke Santal\'{o} type inequality.


title:
A hierarchic multi-level energy method for the control of bi-diagonal
  and mixed n-coupled cascade systems of PDE's by a reduced number of controls

abstract:
  This work is concerned with the exact controllability/observability of
abstract cascade hyperbolic systems by a reduced number of
controls/observations. We prove that the observation of the last component of
the vector state allows to recover the initial energies of all of its
components in suitable functional spaces under a necessary and sufficient
condition on the coupling operators for cascade bi-diagonal systems. The
approach is based on a multi-level energy method which involves $n$-levels of
weakened energies.
  We establish this result for the case of bounded as well as unbounded dual
control operators and under the hypotheses of partial coercivity of the $n-1$
coupling operators on the sub-diagonal of the system.
  We further extend our observability result to mixed bi-diagonal and non
bi-diagonal $n+p$-coupled cascade systems by $p+1$ observations. Applying the
HUM method, we derive the corresponding exact controllability results for
$n$-coupled bi-diagonal cascade and $n+p$-coupled mixed cascade systems. Using
the transmutation method for the wave operator, we prove that the corresponding
heat (resp. Schr\"odinger) multi-dimensional cascade systems are
null-controllable for control regions and coupling regions which are disjoint
from each other and for any positive time for $n \le 5$ for dimensions larger
than $2$, and for any $n \ge 2$ in the one-dimensional case. The controls can
be localized on a subdomain or on the boundary and in the one-dimensional case
the coupling coefficients can be supported in any non-empty subset of the
domain.


title:
Two-Dimensional Sigma Models Related to Non-Abelian Strings in
  Super-Yang-Mills

abstract:
  We review diverse two-dimensional models emerging on the world sheet of
non-Abelian strings in the low-energy limit. Non-Abelian strings are supported
in a class of four-dimensional bulk theories with or without supersymmetry. In
supersymmetric bulk theories we are mostly interested in BPS-saturated strings.
Some of these two-dimensional models, in particular, heterotic models, were
scarcely studied in the past, if at all. Our main emphasis is on the heterotic
N=(0,2) models. We describe their large-N solution. We briefly comment on
N=(0,1) models although so far they are not obtained on the the world sheet of
non-Abelian strings.


title:
Radiation pressure and the distribution of electromagnetic force in
  dielectric media (II)

abstract:
  Using the Finite-Difference-Time-Domain (FDTD) method, we compute the
electromagnetic field distribution in and around dielectric media of various
shapes and optical properties. With the aid of the constitutive relations, we
proceed to compute the bound charge and bound current densities, then employ
the Lorentz law of force to determine the distribution of force-density within
the regions of interest. For a few simple cases where analytical solutions
exist, these solutions are found to be in complete agreement with our numerical
results. We also analyze the distribution of fields and forces in more complex
systems, and discuss the relevance of our findings to experimental
observations. In particular, we demonstrate the single-beam trapping of a
dielectric micro-sphere immersed in a liquid under conditions that are typical
of optical tweezers.


title:
Least-Order Torsion-Gravity for Fermion Fields, and the Non-Linear
  Potentials in the Standard Models

abstract:
  We will consider the least-order torsional completion of gravity for a
spacetime filled with fermionic Dirac matter fields, and we study the effects
of the background-induced non-linear potentials for the matter field themselves
in view of their effects for both standard models of physics: from the one of
cosmology to that of particles, we will discuss the mechanisms of generation of
the cosmological constant and particle masses as well as the phenomenology of
leptonic weak-like forces and neutrino oscillations, the problem of zero-point
energy, how there can be neutral massive fields as candidates for dark matter,
and avoidance of gravitational singularity formation; we will show the way in
which all these different effects can nevertheless be altogether described in
terms of just a single model, which will be thoroughly discussed in the end.


title: Effect of loss on photon-pair generation in nonlinear waveguides arrays

abstract:
  We describe theoretically the process of spontaneous parametric
down-conversion in quadratic nonlinear waveguide arrays in the presence of
linear loss. We derive a set of discrete Schrodinger-type equations for the
biphoton wave function, and the wave function of one photon when the other
photon in a pair is lost. We demonstrate effects arising from loss-affected
interference between the generated photon pairs and show that nonlinear
waveguide arrays can serve as a robust loss-tolerant integrated platform for
the generation of entangled photon states with non-classical spatial
correlations.


title:
Bifurcation of periodic solutions to the singular Yamabe problem on
  spheres

abstract:
  We obtain uncountably many periodic solutions to the singular Yamabe problem
on a round sphere, that blow up along a great circle. These are (complete)
constant scalar curvature metrics on the complement of $S^1$ inside $S^m$,
$m\geq 5$, that are conformal to the round (incomplete) metric and "periodic"
in the sense of being invariant under a discrete group of conformal
transformations. These solutions come from bifurcating branches of constant
scalar curvature metrics on compact quotients of $S^m \setminus S^1\cong
S^{m-2}\times H^2$.


title: Phase Transformation Dynamics in Porous Battery Electrodes

abstract:
  Porous electrodes composed of multiphase active materials are widely used in
Li-ion batteries, but their dynamics are poorly understood. Two-phase models
are largely empirical, and no models exist for three or more phases. Using a
modified porous electrode theory based on non-equilibrium thermodynamics, we
show that experimental phase behavior can be accurately predicted from free
energy models, without artificially placing phase boundaries or fitting the
open circuit voltage. First, we simulate lithium intercalation in porous iron
phosphate, a popular two-phase cathode, and show that the zero-current voltage
gap, sloping voltage plateau and under-estimated exchange currents all result
from size-dependent nucleation and mosaic instability. Next, we simulate porous
graphite, the standard anode with three stable phases, and reproduce
experimentally observed fronts of color-changing phase transformations. These
results provide a framework for physics-based design and control for
electrochemical systems with complex thermodynamics.


title:
Area spectrum of extremal black holes with warped AdS near-horizon
  geometry

abstract:
  In this letter, we provide an alternative method to study the area spectrum
of certain classes of extremal black holes which have near-horizon geometry as
warped AdS. We argue that previous methods which are based on the existence of
quasinormal modes may not be applicable in the extremal limit. The topology
difference of the near-horizon geometry between non-extremal and extremal black
holes implies a separate treatment is needed to study the area discreteness in
the extremal limit. To be specific, we will study area spectrum of
supersymmetric BMPV black holes/black rings and Reissner-Norstroem black holes
at the extremal limit. Inspired by the recently established Kerr/CFT and RN/CFT
correspondence, we propose a new way to quantize the area regardless of the
(non-)existence of quasinormal modes or zero Hawking temperature. At last, we
propose a dilute gas model and harmonic oscillator model which have same
degrees of freedom as the dual CFT.


title: Phase Precoded Compute-and-Forward with Partial Feedback

abstract:
  In this work, we propose phase precoding for the compute-and-forward (CoF)
protocol. We derive the phase precoded computation rate and show that it is
greater than the original computation rate of CoF protocol without precoder. To
maximize the phase precoded computation rate, we need to 'jointly' find the
optimum phase precoding matrix and the corresponding network equation
coefficients. This is a mixed integer programming problem where the optimum
precoders should be obtained at the transmitters and the network equation
coefficients have to be computed at the relays. To solve this problem, we
introduce phase precoded CoF with partial feedback. It is a quantized precoding
system where the relay jointly computes both a quasi-optimal precoder from a
finite codebook and the corresponding network equations. The index of the
obtained phase precoder within the codebook will then be fedback to the
transmitters. A "deep hole phase precoder" is presented as an example of such a
scheme. We further simulate our scheme with a lattice code carved out of the
Gosset lattice and show that significant coding gains can be obtained in terms
of equation error performance.


title:
Radiation pressure and the linear momentum of light in dispersive
  dielectric media

abstract:
  We derive an exact expression for the radiation pressure of a quasi-
monochromatic plane wave incident from the free space onto the flat surface of
a semi-infinite dielectric medium. In order to account for the total optical
momentum (incident plus reflected) that is transferred to the dielectric, the
mechanical momentum acquired by the medium must be added to the rate of flow of
the electromagnetic momentum (the so-called Abraham momentum) inside the
dielectric. We confirm that the electromagnetic momentum travels with the group
velocity of light inside the medium. The photon drag effect, in which the
photons captured in a semiconductor appear to have the Minkowski momentum, is
explained by analyzing a model system consisting of a thin absorptive layer
embedded in a transparent dielectric.


title: Bases of T-meshes and the refinement of hierarchical B-splines

abstract:
  In this paper we consider spaces of bivariate splines of bi-degree (m, n)
with maximal order of smoothness over domains associated to a two-dimensional
grid. We define admissible classes of domains for which suitable combinatorial
technique allows us to obtain the dimension of such spline spaces and the
number of tensor-product B-splines acting effectively on these domains.
Following the strategy introduced recently by Giannelli and Juettler, these
results enable us to prove that under certain assumptions about the
configuration of a hierarchical T-mesh the hierarchical B-splines form a basis
of bivariate splines of bi-degree (m, n) with maximal order of smoothness over
this hierarchical T-mesh. In addition, we derive a sufficient condition about
the configuration of a hierarchical T-mesh that ensures a weighted partition of
unity property for hierarchical B-splines with only positive weights.


title: Quantifying literature quality using complexity criteria

abstract:
  We measured entropy and symbolic diversity for English and Spanish texts
including literature Nobel laureates and other famous authors. Entropy, symbol
diversity and symbol frequency profiles were compared for these four groups. We
also built a scale sensitive to the quality of writing and evaluated its
relationship with the Flesch's readability index for English and the
Szigriszt's perspicuity index for Spanish. Results suggest a correlation
between entropy and word diversity with quality of writing. Text genre also
influences the resulting entropy and diversity of the text. Results suggest the
plausibility of automated quality assessment of texts.


title:
A treatment procedure for Gemini North/NIFS data cubes: application to
  NGC 4151

abstract:
  We present a detailed procedure for treating data cubes obtained with the
Near-Infrared Integral Field Spectrograph (NIFS) of the Gemini North telescope.
This process includes the following steps: correction of the differential
atmospheric refraction, spatial re-sampling, Butterworth spatial filtering,
'instrumental fingerprint' removal and Richardson-Lucy deconvolution. The
clearer contours of the structures obtained with the spatial re-sampling, the
high spatial-frequency noise removed with the Butterworth spatial filtering,
the removed 'instrumental fingerprints' (which take the form of vertical
stripes along the images) and the improvement of the spatial resolution
obtained with the Richardson-Lucy deconvolution result in images with a
considerably higher quality. An image of the Br{\gamma} emission line from the
treated data cube of NGC 4151 allows the detection of individual ionized-gas
clouds (almost undetectable without the treatment procedure) of the narrow-line
region of this galaxy, which are also seen in an [O III] image obtained with
the Hubble Space Telescope. The radial velocities determined for each one of
these clouds seem to be compatible with models of biconical outflows proposed
by previous studies. Considering the observed improvements, we believe that the
procedure we describe in this work may result in more reliable analysis of data
obtained with this instrument.


title:
A Block Successive Upper Bound Minimization Method of Multipliers for
  Linearly Constrained Convex Optimization

abstract:
  Consider the problem of minimizing the sum of a smooth convex function and a
separable nonsmooth convex function subject to linear coupling constraints.
Problems of this form arise in many contemporary applications including signal
processing, wireless networking and smart grid provisioning. Motivated by the
huge size of these applications, we propose a new class of first order
primal-dual algorithms called the block successive upper-bound minimization
method of multipliers (BSUM-M) to solve this family of problems. The BSUM-M
updates the primal variable blocks successively by minimizing locally tight
upper-bounds of the augmented Lagrangian of the original problem, followed by a
gradient type update for the dual variable in closed form. We show that under
certain regularity conditions, and when the primal block variables are updated
in either a deterministic or a random fashion, the BSUM-M converges to the set
of optimal solutions. Moreover, in the absence of linear constraints, we show
that the BSUM-M, which reduces to the block successive upper-bound minimization
(BSUM) method, is capable of linear convergence without strong convexity.


title:
Magnetic Field Amplification and Saturation in Turbulence Behind a
  Relativistic Shock

abstract:
  We have investigated via two-dimensional relativistic MHD simulations the
long-term evolution of turbulence created by a relativistic shock propagating
through an inhomogeneous medium. In the postshock region, magnetic field is
strongly amplified by turbulent motions triggered by preshock density
inhomogeneities. Using a long-simulation box we have followed the
magnetic-field amplification until it is fully developed and saturated. The
turbulent velocity is sub-relativistic even for a strong shock. Magnetic-field
amplification is controled by the turbulent motion and saturation occurs when
the magnetic energy is comparable to the turbulent kinetic energy.
Magnetic-field amplification and saturation depend on the initial strength and
direction of the magnetic field in the preshock medium, and on the shock
strength. If the initial magnetic field is perpendicular to the shock normal,
the magnetic field is first compressed at the shock and then can be amplified
by turbulent motion in the postshock region. Saturation occurs when the
magnetic energy becomes comparable to the turbulent kinetic energy in the
postshock region. If the initial magnetic field in the preshock medium is
strong, the postshock region becomes turbulent but significant field
amplification does not occur. If the magnetic energy after shock compression is
larger than the turbulent kinetic energy in the postshock region, significant
field amplification does not occur. We discuss possible applications of our
results to gamma-ray bursts and active galactic nuclei.


title: Graph-Theoretic Approach to Quantum Correlations

abstract:
  Correlations in Bell and noncontextuality inequalities can be expressed as a
positive linear combination of probabilities of events. Exclusive events can be
represented as adjacent vertices of a graph, so correlations can be associated
to a subgraph. We show that the maximum value of the correlations for
classical, quantum, and more general theories is the independence number, the
Lov\'asz number, and the fractional packing number of this subgraph,
respectively. We also show that, for any graph, there is always a correlation
experiment such that the set of quantum probabilities is exactly the
Gr\"otschel-Lov\'asz-Schrijver theta body. This identifies these combinatorial
notions as fundamental physical objects and provides a method for singling out
experiments with quantum correlations on demand.


title: Angular momentum of circularly polarized light in dielectric media

abstract:
  A circularly polarized plane-wave is known to have no angular momentum when
examined through Maxwell's equations. This, however, contradicts the
experimentally observed facts, where finite segments of plane waves are known
to be capable of imparting angular momentum to birefringent platelets. Using a
superposition of four plane-waves propagating at slightly different angles to a
common direction, we derive an expression for the angular momentum density of a
single plane-wave in the limit when the propagation directions of the four
beams come into alignment. We proceed to use this four-beam technique to
analyze the conservation of angular momentum when a plane-wave enters a
dielectric slab from the free space. The angular momentum of the beam is shown
to decrease upon entering the dielectric medium, by virtue of the fact that the
incident beam exerts a torque on the slab surface at the point of entry. When
the beam leaves the slab, it imparts an equal but opposite torque to the exit
facet, thus recovering its initial angular momentum upon re-emerging into the
free-space. Along the way, we derive an expression for the outward-directed
force of a normally incident, finite-diameter beam on a dielectric surface; the
possible relationship between this force and the experimentally observed
bulging of a liquid surface under intense illumination is explored.


title:
Extensions of locally compact abelian, torsion-free groups by compact
  torsion abelian groups

abstract:
  Let $X$ be a compact torsion abelian group. In this paper, we show that an
extension of $F_{p}$ by $X$ splits where $F_{p}$ is the p-adic number group and
$p$ a prime number. Also, we show that an extension of a torsion-free,
non-divisible LCA group by $X$ is not split.


title: Bounds on determinants of perturbed diagonal matrices

abstract:
  We give upper and lower bounds on the determinant of a perturbation of the
identity matrix or, more generally, a perturbation of a nonsingular diagonal
matrix. The matrices considered are, in general, diagonally dominant. The lower
bounds are best possible, and in several cases they are stronger than
well-known bounds due to Ostrowski and other authors. If $A = I-E$ is an $n
\times n$ matrix and the elements of $E$ are bounded in absolute value by
$\varepsilon \le 1/n$, then a lower bound of Ostrowski (1938) is $\det(A) \ge
1-n\varepsilon$. We show that if, in addition, the diagonal elements of $E$ are
zero, then a best-possible lower bound is \[\det(A) \ge
(1-(n-1)\varepsilon)\,(1+\varepsilon)^{n-1}.\] Corresponding upper bounds are
respectively \[\det(A) \le (1 + 2\varepsilon + n\varepsilon^2)^{n/2}\] and
\[\det(A) \le (1 + (n-1)\varepsilon^2)^{n/2}.\] The first upper bound is
stronger than Ostrowski's bound (for $\varepsilon < 1/n$) $\det(A) \le (1 -
n\varepsilon)^{-1}$. The second upper bound generalises Hadamard's inequality,
which is the case $\varepsilon = 1$.
  A necessary and sufficient condition for our upper bounds to be best possible
for matrices of order $n$ and all positive $\varepsilon$ is the existence of a
skew-Hadamard matrix of order $n$.


title: Reverse Edge Cut-Set Bounds for Secure Network Coding

abstract:
  We consider the problem of secure communication over a network in the
presence of wiretappers. We give a new cut-set bound on secrecy capacity which
takes into account the contribution of both forward and backward edges crossing
the cut, and the connectivity between their endpoints in the rest of the
network. We show the bound is tight on a class of networks, which demonstrates
that it is not possible to find a tighter bound by considering only cut set
edges and their connectivity.


title:
N derivatives are necessary for order N+1 convergence in quadrature: a
  converse result

abstract:
  Results on the error bounds of quadrature methods are well known - most state
that if the method has degree N, and the integrand has N derivatives, then the
error is order N+1. We prove here a converse: that if the integrand fails to
have N derivatives, even only at a finite number of points, no method,
regardless of its degree, can guarantee convergence more than order N. Even if
the integrand fails to have N derivatives at just 3 (for even N, 2) points, no
method can produce order more than N+1 convergence. This is done by an
adversarial proof: we explicitly construct the functions that exhibit such
error; simple splines turn out to suffice.


title: How "Quantum" is the D-Wave Machine?

abstract:
  Recently there has been intense interest in claims about the performance of
the D-Wave machine. In this paper, we outline a simple classical model, and
show that it achieves excellent correlation with published input-output
behavior of the D-Wave One machine on 108 qubits. While raising questions about
"how quantum" the D-Wave machine is, the new model also provides additional
algorithmic insights into the nature of the native computational problem solved
by the D-Wave machine.


title:
Cellular Downlink Performance with Base Station Sleeping, User
  Association, and Scheduling

abstract:
  Base station (BS) sleeping has emerged as a viable solution to enhance the
overall network energy efficiency by inactivating the underutilized BSs.
However, it affects the performance of users in sleeping cells depending on
their BS association criteria, their channel conditions towards the active BSs,
and scheduling criteria and traffic loads at the active BSs. This paper
characterizes the performance of cellular systems with BS sleeping by
developing a systematic framework to derive the spectral efficiency and outage
probability of downlink transmission to the sleeping cell users taking into
account the aforementioned factors. In this context, we develop a user
association scheme in which a typical user in a sleeping cell selects a BS with
\textbf{M}aximum best-case \textbf{M}ean channel \textbf{A}ccess
\textbf{P}robability (MMAP) which is calculated by all active BSs based on
their existing traffic loads. We consider both greedy and round-robin schemes
at active BSs for scheduling users in a channel. Once the association is
performed, the exact access probability for a typical sleeping cell user and
the statistics of its received signal and interference powers are derived to
evaluate the spectral and energy efficiencies of transmission. For the sleeping
cell users, we also consider the conventional \textbf{M}aximum
\textbf{R}eceived \textbf{S}ignal \textbf{P}ower (MRSP)-based user association
scheme along with greedy and round-robin schemes at the BSs. The impact of
cell-zooming is incorporated in the derivations to analyze its feasibility in
reducing the coverage holes created by BS sleeping. Numerical results show the
trade-offs between spectral efficiency and energy efficiency in various network
scenarios. The accuracy of the analysis is verified through Monte-Carlo
simulations.


title: MR PRISM - Spectral Analysis Tool for the CRISM

abstract:
  We describe a computer application designed to analyze hyperspectral data
collected by the Compact Infrared Spectrometer for Mars (CRISM). The
application links the spectral, imaging and mapping perspectives on the
eventual CRISM dataset by presenting the user with three different ways to
analyze the data.
  One of the goals when developing this instrument is to build in the latest
algorithms for detection of spectrally compelling targets on the surface of the
Red Planet, so they may be available to the Planetary Science community without
cost and with a minimal learning barrier to cross. This will allow the
Astrobiology community to look for targets of interest such as hydrothermal
minerals, sulfate minerals and hydrous minerals and be able to map the extent
of these minerals using the most up-to-date and effective algorithms.
  The application is programmed in Java and will be made available for Windows,
Mac and Linux platforms. Users will be able to embed Groovy scripts into the
program in order to extend its functionality. The first collection of CRISM
data will occur in September of 2006 and this data will be made publicly
available six months later via the Planetary Datasystem (PDS). Potential users
in the community should therefore look forward to a release date mid-2007.
  Although exploration of the CRISM data set is the motivating force for
developing these software tools, the ease of writing additional Groovy scripts
to access other data sets makes the tools useful for mineral exploration, crop
management, and characterization of extreme environments here on Earth or other
terrestrial planets. The system can be easily implemented for use by high
school, college, and graduate level students.


title:
Wavelength-Selective Switches for Mode-Division Multiplexing: Scaling
  and Performance Analysis

abstract:
  Wavelength-selective switches for mode-division-multiplexing systems are
designed by scaling switches from single-mode systems. All modes at a given
wavelength are switched as a unit, which is necessary in systems with
substantial mode coupling, and minimizes the number of ports required to
accommodate a given traffic volume. When a pure mode is present at the input,
modal transmission and coupling coefficients are mode-dependent and may be
computed using a simple mode-clipping model. When multiple modes are present,
interference between modes alters the transmission and coupling coefficients,
shifting the passband center frequency and changing its bandwidth.
Mode-coupling matrices are used to compute mixed modes having the narrowest or
widest bandwidths, or having the largest center-frequency offsets. In a
specific design for graded-index fiber, five mode groups and 50-GHz channel
spacing, the one-sided bandwidth may change up to $\pm$3.6 GHz. In a system
with many cascaded switches and strong mode coupling, the end-to-end response
per switch may be characterized by a mode-averaged transmission coefficient.


title:
Spectral radius and signless Laplacian spectral radius of strongly
  connected digraphs

abstract:
  Let D be a strongly connected digraph and A(D) be the adjacency matrix of D.
Let diag(D) be the diagonal matrix with outdegrees of the vertices of D and
Q(D) = diag(D) + A(D) be the signless Laplacian matrix of D. The spectral
radius of Q(D) is called the signless Laplacian spectral radius of D, denoted
by q(D). In this paper, we give sharp bound on q(D) with outdegree sequence and
compare the bound with some known bounds, establish some sharp upper or lower
bound on q(D) with some given parameter such as clique number, girth or vertex
connectivity, and characterize the corresponding extremal digraph or proposed
open problem. In addition, we also determine the unique digraph which achieves
the minimum (or maximum), the second minimum (or maximum), the third minimum,
the fourth minimum spectral radius and signless Laplacian spectral radius among
all strongly connected digraphs, and answer the open problem proposed by
Lin-Shu [H.Q. Lin, J.L. Shu, A note on the spectral characterization of
strongly connected bicyclic digraphs, Linear Algebra Appl. 436 (2012)
2524{2530].


title: On systems of equations in free abelian groups

abstract:
  In this paper we study the asymptotic probability that a random system of
equations in free abelian group $\mathbb{Z}^m$ of rank $m$ is solvable. Denote
$SAT(\mathbb{Z}^m, k, n)$ and $SAT_{\mathbb{Q}^m}(\mathbb{Z}^m, k, n)$ the sets
of all systems of $n$ equations in $k$ variables in the group $\mathbb{Z}^m$
solvable in $\mathbb{Z}^m$ and $\mathbb{Q}^m$ respectively. We show that
asymptotic density of the set $SAT_{\mathbb{Q}^m}(\mathbb{Z}^m, k, n)$ is equal
to $1$ for $n \leq k$, and is equal to $0$ for $n > k$. For $n < k$ we give
nontrivial estimates for upper and lower asymptotic densities of the set
$SAT(\mathbb{Z}^m, k, n)$. When $n > k$ the set $SAT(\mathbb{Z}^m, k, n)$ is
negligible. Also for $n \leq k$ we provide some connection between asymptotic
density of the set $SAT(\mathbb{Z}^m, k, n)$ and sums over full rank matrices
involving their greatest divisors.


title: Hiding a neutron star inside a wormhole

abstract:
  We consider neutron-star-plus-wormhole configurations supported by a massless
ghost scalar field. The neutron fluid is modeled by an anisotropic equation of
state. When the central energy density of the fluid is of comparable magnitude
to the one of the scalar field, configurations with an equator at the center
and a double throat arise. These double-throat wormholes can be either
partially or completely filled by the neutron fluid. In the latter case, the
passage of light - radiated by the neutron matter - through these wormholes is
studied. A stability analysis indicates that all considered configurations are
unstable with respect to linear perturbations, independent of whether the fluid
is isotropic or anisotropic.


title: Exact WKB analysis and cluster algebras

abstract:
  We develop the mutation theory in the exact WKB analysis using the framework
of cluster algebras. Under a continuous deformation of the potential of the
Schr\"odinger equation on a compact Riemann surface, the Stokes graph may
change the topology. We call this phenomenon the mutation of Stokes graphs.
Along the mutation of Stokes graphs, the Voros symbols, which are monodromy
data of the equation, also mutate due to the Stokes phenomenon. We show that
the Voros symbols mutate as variables of a cluster algebra with surface
realization. As an application, we obtain the identities of Stokes
automorphisms associated with periods of cluster algebras. The paper also
includes an extensive introduction of the exact WKB analysis and the surface
realization of cluster algebras for nonexperts.


title: Coherent noise source identification in multi channel analysis

abstract:
  The evaluation of coherent noise can provide useful information in the study
of detectors. The identification of coherent noise sources is also relevant for
uncertainty calculations in analyse where several channels are combined. The
study of the covariance matrix give information about coherent noises. Since
covariance matrix of high dimension data could be difficult to analyse, the
development of analysis tools is needed. Principal Component Analysis (PCA) is
a powerful tool for such analysis. It has been shown that we can use PCA to
find coherent noises in ATLAS calorimeter or the CALICE Si-W electromagnetic
calorimeter physics prototype. However, if several coherent noise sources are
combined, the interpretation of the PCA may become complicated.
  In this paper, we present another method based on the study of the covariance
matrix to identify noise sources. This method has been developed for the study
of front end ASICs dedicated to CALICE calorimeters. These calorimeters are
designed and studied for experiments at the ILC. We also study the reliability
of the method with simulations. Although this method has been developped for a
specific application, it can be used for any multi channel analysis.


title: Universal quantum computation with weakly integral anyons

abstract:
  Harnessing non-abelian statistics of anyons to perform quantum computational
tasks is getting closer to reality. While the existence of universal anyons by
braiding alone such as the Fibonacci anyon is theoretically a possibility,
accessible anyons with current technology all belong to a class that is called
weakly integral---anyons whose squared quantum dimensions are integers. We
analyze the computational power of the first non-abelian anyon system with only
integral quantum dimensions---$D(S_3)$, the quantum double of $S_3$. Since all
anyons in $D(S_3)$ have finite images of braid group representations, they
cannot be universal for quantum computation by braiding alone. Based on our
knowledge of the images of the braid group representations, we set up three
qutrit computational models. Supplementing braidings with some measurements and
ancillary states, we find a universal gate set for each model.


title: Invariance of quantum rings under ordinary flops: III

abstract:
  The paper is Part III of our ongoing project to study a case of Crepant
Transformation Conjecture: K-equivalence Conjecture for ordinary flops. In this
paper we prove the invariance of quantum rings for general ordinary flops,
whose local models are certain non-split toric bundles over arbitrary smooth
base. An essential ingredient in the proof is a quantum splitting principle,
which reduces a statement in Gromov--Witten theory on non-split bundles to the
case of split bundles.


title: An extremal eigenvalue problem for the Wentzell-Laplace operator

abstract:
  We consider the question of giving an upper bound for the first nontrivial
eigenvalue of the Wentzell-Laplace operator of a domain $\Omega$, involving
only geometrical informations. We provide such an upper bound, by generalizing
Brock's inequality concerning Steklov eigenvalues, and we conjecture that balls
maximize the Wentzell eigenvalue, in a suitable class of domains, which would
improve our bound. To support this conjecture, we prove that balls are critical
domains for the Wentzell eigenvalue, in any dimension, and that they are local
maximizers in dimension 2 and 3, using an order two sensitivity analysis. We
also provide some numerical evidence.


title:
The classical KAM theorem for Hamiltonian systems via rational
  approximations

abstract:
  In this paper, we give a new proof of the classical KAM theorem on the
persistence of an invariant quasi-periodic torus, whose frequency vector
satisfies the Bruno-R\"ussmann condition, in real-analytic non-degenerate
Hamiltonian systems close to integrable. The proof, which uses rational
approximations instead of small divisors estimates, is an adaptation to the
Hamiltonian setting of the method we introduced in a previous work for
perturbations of constant vector fields on the torus.


title:
Large Deformation Diffeomorphic Metric Mapping And Fast-Multipole
  Boundary Element Method Provide New Insights For Binaural Acoustics

abstract:
  This paper describes how Large Deformation Diffeomorphic Metric Mapping
(LDDMM) can be coupled with a Fast Multipole (FM) Boundary Element Method (BEM)
to investigate the relationship between morphological changes in the head,
torso, and outer ears and their acoustic filtering (described by Head Related
Transfer Functions, HRTFs). The LDDMM technique provides the ability to study
and implement morphological changes in ear, head and torso shapes. The FM-BEM
technique provides numerical simulations of the acoustic properties of an
individual's head, torso, and outer ears. This paper describes the first
application of LDDMM to the study of the relationship between a listener's
morphology and a listener's HRTFs. To demonstrate some of the new capabilities
provided by the coupling of these powerful tools, we examine the classical
question of what it means to ``listen through another individual's outer
ears.'' This work utilizes the data provided by the Sydney York Morphological
and Acoustic Recordings of Ears (SYMARE) database.


title:
Holography in flat spacetime: 4D theories and electromagnetic duality on
  the border

abstract:
  We consider a free topological model in 5D euclidean flat spacetime, built
from two rank-2 tensor fields. Despite the fact that the bulk of the model does
not have any particular physical interpretation, on its 4D planar edge
nontrivial gauge field theories are recovered, whose features are entirely
determined by the gauge and discrete symmetries of the bulk. In particular no
4D dynamics can be obtained without imposing a Time Reversal invariance in the
bulk. Remarkably, one of the two possible edge models selected by the Time
Reversal symmetries displays a true electromagnetic duality, which relates
strong and weak coupling regimes. Moreover this same model, when considered
on-shell, coincides with the Maxwell theory, which therefore can be thought of
as a 4D boundary theory of a seemingly harmless 5D topological model.


title: Multi-particle Processes and Tamed Ultraviolet Divergences

abstract:
  New approach to computing the amplitudes of multi-particle processes in
renormalizable quantum field theories is presented. Its major feature is a
separation of the renormalization from the computation. Within the suggested
approach new computational rules are formulated. According to the new rules,
the amplitudes under computation are expressed as a sum of effective Feynman
amplitudes whose vertexes are the complete amplitudes of the processes
involving not more than four particles, and the lines are the complete
two-point functions. The new rules include prescriptions for computing the
combinatorial factors by each amplitude. It is demonstrated that due to these
prescriptions the combinatorial factors by the amplitudes that are divergent in
the ultraviolet in four space-time dimensions vanish. Because of this, the
computations within the new approach do not involve the ultraviolet
renormalization. It is observed that the combinatorics of the new rules
determines the dimension of the space-time.


title: Three-axis Hall transducer based on semiconductor microtubes

abstract:
  A three-axis Hall transducer based on GaAs/AlGaAs/InGaAs microtubes has been
fabricated. The possibility of simultaneous measurement of all the three
magnetic field components with such a transducer was demonstrated. It was also
shown possible to pack the free-standing parts of the transducer with
polydimethylsiloxane for protection of those parts from mechanical actions.


title: Acquisition of a Project-Specific Process

abstract:
  Currently, proposed development processes are often considered too generic
for operational use. This often leads to a misunderstanding of the
project-specific processes and its refuse. One reason for non-appropriate
project-specific processes is insufficient support for the tailoring of generic
processes to project characteristics and context constraints. To tackle this
problem, we propose a method for the acquisition of a project-specific process.
This method uses a domain-specific process line for top-down process tailoring
and supports bottom-up refinement of the defined generic process based on
tracking process activities. The expected advantage of the method is tailoring
efficiency gained by usage of a process line and higher process adherence
gained by bottom-up adaptation of the process. The work described was conducted
in the automotive domain. This article presents an overview of the so-called
Emergent Process Acquisition method (EPAc) and sketches an initial validation
study.


title:
Size measurement of dynamically generated hadronic resonances with
  finite volume effect

abstract:
  The structures of the hyperon resonance $\Lambda (1405)$ and the scalar
mesons $\sigma$, $f_{0}(980)$, and $a_{0}(980)$ are investigated based on the
coupled-channels chiral dynamics with finite volume effect. The finite volume
effect is utilized to extract the coupling constant, compositeness, and mean
squared distance between two constituents of a Feshbach resonance state as well
as a stable bound state. In this framework, the real-valued size of the
resonance can be defined from the downward shift of the resonance pole
according to the decreasing finite box size $L$ on a given closed channel. As a
result, we observe that, when putting the $\bar{K}N$ and $K\bar{K}$ channels
into a finite box while other channels being unchanged, the poles of the higher
$\Lambda (1405)$ and $f_{0}(980)$ move to lower energies while other poles do
not show downward mass shift, which implies large $\bar{K}N$ and $K\bar{K}$
components inside higher $\Lambda (1405)$ and $f_{0}(980)$, respectively.
Extracting structures of $\Lambda (1405)$ and $f_{0}(980)$ in our method, we
find that the compositeness of $\bar{K}N$ ($K\bar{K}$) inside $\Lambda (1405)$
[$f_{0}(980)$] is 0.82-1.03 (0.73-0.97) and the mean distance between two
constituents is evaluated as 1.7-1.9 fm (2.6-3.0 fm).


title: Monte Carlo simulations of Landau-Ginzburg model for membranes

abstract:
  The Landau-Ginzburg (LG) model for membranes is numerically studied on
triangulated spheres in ${\bf R}^3$. The LG model is in sharp contrast to the
model of Helfrich-Polyakov (HP). The reason for this difference is that the
curvature energy of the LG (HP) Hamiltonian is defined by means of the
tangential (normal) vector of the surface. For this reason the curvature energy
of the LG model includes the in-plane bending or shear energy component, which
is not included in the curvature energy of the HP model. From the simulation
data, we find that the LG model undergoes a first-order collapse transition.
The results of the LG model in the higher dimensional spaces ${\bf R}^d (d>3)$
and on the self-avoiding surfaces in ${\bf R}^3$ are presented and discussed.
We also study the David-Guitter (DG) model, which is a variant of the LG model,
and find that the DG model undergoes a first-order transition. It is also found
that the transition can be observed only on the homogeneous surfaces, which are
composed of almost uniform triangles according to the condition that the
induced metric ${\partial_a {\bf r}}\cdot{\partial_b {\bf r}}$ is close to
$\delta_{ab}$.


title: An introduction to knot Floer homology

abstract:
  This is a survey article about knot Floer homology. We present three
constructions of this invariant: the original one using holomorphic disks, a
combinatorial description using grid diagrams, and a combinatorial description
in terms of the cube of resolutions. We discuss the geometric information
carried by knot Floer homology, and the connection to three- and
four-dimensional topology via surgery formulas. We also describe some
conjectural relations to Khovanov-Rozansky homology.


title: Balanced metrics on twisted Higgs Bundles

abstract:
  A twisted Higgs bundle on a K\"ahler manifold $X$ is a pair $(E,\phi)$
consisting of a holomorphic vector bundle $E$ and a holomorphic bundle morphism
$\phi\colon M\otimes E \to E$ for some holomorphic vector bundle $M$. Such
objects were first considered by Hitchin when $X$ is a curve and $M$ is the
tangent bundle of $X$, and also by Simpson for higher dimensional base. The
Hitchin-Kobayashi correspondence for such pairs states that $(E,\phi)$ is
polystable if and only if $E$ admits a hermitian metric solving the Hitchin
equation. This correspondence is a powerful tool to decide whether there exists
a solution of the equation, but it provides little information as to the actual
solution. In this paper we study a quantization of this problem that is
expressed in terms of finite dimensional data and balanced metrics that give
approximate solutions to the Hitchin equation. Motivation for this study comes
from work of Donagi--Wijnholt on arXiv:1104.2610 concerning balanced metrics
for the Vafa-Witten equations.

categories: math.DG hep-th math-ph math.AG math.CV math.MP


title: The Na-O anticorrelation in horizontal branch stars. IV. M22

abstract:
  We obtained high-resolution spectra for 94 candidate stars belonging to the
HB of M22 with FLAMES. The HB stars we observed span a restricted temperature
range (7,800<Teff<11,000 K), where about 60% of the HB stars of M22 are. Within
our sample, we can distinguish three groups of stars segregated (though
contiguous) in colours: Group 1 (49 stars) is metal-poor, N-normal, Na-poor and
O-rich with abundances that match those determined for the primordial group of
RGB stars from previous studies. Group 2 (23 stars) is still metal-poor, but it
is N- and Na-rich, though only very mildly depleted in O. We can identify this
intermediate group as the progeny of the metal-poor RGB stars that occupy an
intermediate location along the Na-O anti-correlation. The third group (20
stars) is metal-rich, Na-rich, and O-rich and likely corresponds to the most
O-rich component of the previously found metal-rich RGB population. We did not
observe any severely O-depleted stars and we think that the progeny of these
stars falls on the hotter part of the HB. The metal-rich population is also
over-abundant in Sr, in agreement with results for corresponding RGB and SGB
stars. However, we do not find any significant variation in the ratio between
the sum of N and O abundances to Fe. There is some evidence of an enhancement
of He content for Groups 2 and 3 stars (Y=0.338\pm 0.014\pm 0.05). Our results
agree with the proposition that chemical composition drives the location of
stars along the HB of a GC. Furthermore, we found a number of fast rotators.
They are concentrated in a restricted temperature range along the HB of M22.


title:
A Fast String Matching Algorithm Based on Lowlight Characters in the
  Pattern

abstract:
  We put forth a new string matching algorithm which matches the pattern from
neither the left nor the right end, instead a special position. Comparing with
the Knuth-Morris-Pratt algorithm and the Boyer-Moore algorithm, the new
algorithm is more flexible to pick the position for starting comparisons. The
option really brings it a saving in cost.


title:
Bright Integrated Photon-Pair Source for Practical Passive Decoy-State
  Quantum Key Distribution

abstract:
  We report on a bright, nondegenerate type-I parametric down-conversion
source, which is well suited for passive decoy-state quantum key distribution.
We show the photon-number-resolved analysis over a broad range of pump powers
and we prove heralded higher-order $n$-photon states up to $n=4$. The inferred
photon click statistics exhibit excellent agreements to the theoretical
predictions. From our measurement results we conclude that our source meets the
requirements to avert photon-number-splitting attacks.


title: Orlicz Spaces with Bicomplex Scalars

abstract:
  In this paper we define bicomplex Orlicz space with hyperbolic valued
Luxemburg norm and discussed some of their properties. We have also partially
characterize an integral representation of a $\mathbb{D}$-valued convex
function. Further we have shown that the spectrum of the unilateral shift
operator on $l^2(\mathbb{BC})$ is the null cone $\mathcal{NC}$.


title:
The UBV Color Evolution of Classical Novae. I. Nova-Giant Sequence in
  the Color-Color Diagram

abstract:
  We identified a general course of classical nova outbursts in the B-V versus
U-B color-color diagram. It is reported that novae show spectra similar to
those of A--F supergiants near optical light maximum. However, they do not
follow the supergiant sequence in the color-color diagram, neither the
blackbody nor the main-sequence sequence. Instead, we found that novae evolve
along a new sequence in the pre-maximum and near-maximum phases, which we call
"the nova-giant sequence." This sequence is parallel to but \Delta (U-B)
\approx -0.2 mag bluer than the supergiant sequence. This is because the mass
of a nova envelope is much (\sim10^{-4} times) less than that of a normal
supergiant. After optical maximum, its color quickly evolves back blueward
along the same nova-giant sequence and reaches the point of free-free emission
(B-V=-0.03, U-B=-0.97), which coincides with the intersection of the blackbody
sequence and the nova-giant sequence, and remains there for a while. Then the
color evolves leftward (blueward in B-V but almost constant in U-B), owing
mainly to the development of strong emission lines. This is the general course
of nova outbursts in the color-color diagram, which was deduced from eight
well-observed novae in various speed classes. For a nova with unknown
extinction, we can determine a reliable value of the color excess by matching
the observed track of the target nova with this general course. This is a new
and convenient method for obtaining the color excesses of classical novae.
Using this method, we redetermined the color excesses of twenty well-observed
novae. The obtained color excesses are in reasonable agreement with the
previous results, which in turn supports the idea of our general track of nova
outbursts.


title:
Fundamental Limits in Correlated Fading MIMO Broadcast Channels:
  Benefits of Transmit Correlation Diversity

abstract:
  We investigate asymptotic capacity limits of the Gaussian MIMO broadcast
channel (BC) with spatially correlated fading to understand when and how much
transmit correlation helps the capacity. By imposing a structure on channel
covariances (equivalently, transmit correlations at the transmitter side) of
users, also referred to as \emph{transmit correlation diversity}, the impact of
transmit correlation on the power gain of MIMO BCs is characterized in several
regimes of system parameters, with a particular interest in the large-scale
array (or massive MIMO) regime. Taking the cost for downlink training into
account, we provide asymptotic capacity bounds of multiuser MIMO downlink
systems to see how transmit correlation diversity affects the system
multiplexing gain. We make use of the notion of joint spatial division and
multiplexing (JSDM) to derive the capacity bounds. It is advocated in this
paper that transmit correlation diversity may be of use to significantly
increase multiplexing gain as well as power gain in multiuser MIMO systems. In
particular, the new type of diversity in wireless communications is shown to
improve the system multiplexing gain up to by a factor of the number of degrees
of such diversity. Finally, performance limits of conventional large-scale MIMO
systems not exploiting transmit correlation are also characterized.


title:
Electronic Evidence of an Insulator-Superconductor Transition in
  Single-Layer FeSe/SrTiO3 Films

abstract:
  In high temperature cuprate superconductors, it is now generally agreed that
the parent compound is a Mott insulator and superconductivity is realized by
doping the antiferromagnetic Mott insulator. In the iron-based superconductors,
however, the parent compound is mostly antiferromagnetic metal, raising a
debate on whether an appropriate starting point should go with an itinerant
picture or a localized picture. It has been proposed theoretically that the
parent compound of the iron-based superconductors may be on the verge of a Mott
insulator, but so far no clear experimental evidence of doping-induced Mott
transition has been available. Here we report an electronic evidence of an
insulator-superconductor transition observed in the single-layer FeSe films
grown on the SrTiO3 substrate. By taking angle-resolved photoemission
measurements on the electronic structure and energy gap, we have identified a
clear evolution of an insulator to a superconductor with the increasing doping.
This observation represents the first example of an insulator-superconductor
transition via doping observed in the iron-based superconductors. It indicates
that the parent compound of the iron-based superconductors is in proximity of a
Mott insulator and strong electron correlation should be considered in
describing the iron-based superconductors.


title:
Bayesian Properties of Normalized Maximum Likelihood and its Fast
  Computation

abstract:
  The normalized maximized likelihood (NML) provides the minimax regret
solution in universal data compression, gambling, and prediction, and it plays
an essential role in the minimum description length (MDL) method of statistical
modeling and estimation. Here we show that the normalized maximum likelihood
has a Bayes-like representation as a mixture of the component models, even in
finite samples, though the weights of linear combination may be both positive
and negative. This representation addresses in part the relationship between
MDL and Bayes modeling. This representation has the advantage of speeding the
calculation of marginals and conditionals required for coding and prediction
applications.


title:
Probing quantum and classical turbulence analogy through global
  bifurcations in a von K\'arm\'an liquid Helium experiment

abstract:
  We report measurements of the dissipation in the Superfluid Helium high
REynold number von Karman flow (SHREK) experiment for different forcing
conditions, through a regime of global hysteretic bifurcation. Our
macroscopical measurements indicate no noticeable difference between the
classical fluid and the superfluid regimes, thereby providing evidence of the
same dissipative anomaly and response to asymmetry in fluid and superfluid
regime. %In the latter case, A detailed study of the variations of the
hysteretic cycle with Reynolds number supports the idea that (i) the stability
of the bifurcated states of classical turbulence in this closed flow is partly
governed by the dissipative scales and (ii) the normal and the superfluid
component at these temperatures (1.6K) are locked down to the dissipative
length scale.


title:
Gravitational lensing and frame dragging of light in the Kerr-Newman and
  the Kerr-Newman-(anti) de Sitter black hole spacetimes

abstract:
  The null geodesics that describe photon orbits in the spacetime of a rotating
electrically charged black hole (Kerr-Newman) are solved exactly including the
contribution from the cosmological constant. We derive elegant closed form
solutions for relativistic observables such as the deflection angle and frame
dragging effect that a light ray experiences in the gravitational fields (i) of
a Kerr-Newman black hole and (ii) of a Kerr-Newman-de Sitter black hole. We
then solve the more involved problem of treating a Kerr-Newman black hole as a
gravitational lens, i.e. a KN black hole along with a static source of light
and a static observer both located far away but otherwise at arbitrary
positions in space. For this model, we derive the analytic solutions of the
lens equations in terms of Appell and Lauricella hypergeometric functions and
the Weierstra\ss modular form. The exact solutions derived for null, spherical
polar and non-polar orbits, are applied for the calculation of frame dragging
for the orbit of a photon around the galactic centre, assuming that the latter
is a Kerr-Newman black hole. We also apply the exact solution for the
deflection angle of an equatorial light ray in the gravitational field of a
Kerr-Newman black hole for the calculation of bending of light from the
gravitational field of the galactic centre for various values of the Kerr
parameter, electric charge and impact factor. In addition, we derive analytic
expressions for the Maxwell tensor components for a
Zero-Angular-Momentum-Observer (ZAMO) in the Kerr-Newman-de Sitter spacetime.


title:
A Dynamical Model of Decision-Making Behaviour in a Network of Consumers
  with Applications to Energy Choices

abstract:
  A consumer Behaviour model is considered in the context of a network of
interacting individuals in an energy market. We propose and analyse a simple
dynamical model of an ensemble of coupled active elements mimicking consumers'
Behaviour, where ``word-of-mouth'' interactions between individuals is
important. A single element is modelled using the automatic control system
framework. Assuming local (nearest neighbour) coupling we study the evolution
of chains and lattices of the model consumers on variation of the coupling
strength and initial conditions. The results are interpreted as the dynamics of
the decision-making process by the energy-market consumers. We demonstrate that
a pitchfork bifurcation to the homogeneous solution leads to bistability of
stationary regimes, while the autonomous system is always monostable. In
presence of inhomogeneities this results in the formation of clusters of
sharply positive and negative opinions. We also find that, depending on the
coupling strength, the perturbations caused by inhomogeneities can be
exponentially Localised in space or de-Localised. In the latter case the
coarse-graining of opinion clusters occurs.


title: Phase space monitoring of exciton-polariton multistability

abstract:
  Dynamics of exciton-polariton multistability is theoretically investigated.
Phase portraits are used as a tool to enlighten the microscopic phenomena which
influence spin multistability of a confined polariton field as well as
ultrafast reversible spin switching. The formation of a non-radiative
reservoir, due to polariton pairing into biexcitons is found to play the lead
role in the previously reported spin switching experiments. Ways to tailor this
reservoir formation are discussed in order to obtain optimal spin switching
reliability.


title: Evolution of the extinction curves in galaxies

abstract:
  We investigate the evolution of extinction curves in galaxies based on our
evolution model of grain size distribution. In this model, we considered
various processes: dust formation by SNe II and AGB stars, dust destruction by
SN shocks in the ISM, metal accretion onto the surface of grains (referred to
as grain growth), shattering and coagulation. We find that the extinction curve
is flat in the earliest stage of galaxy evolution. As the galaxy is enriched
with dust, shattering becomes effective to produce a large abundance of small
grains ($a \la 0.01\;\mu$m). Then, grain growth becomes effective at small
grain radii, forming a bump at $a \sim 10^{-3}${--}$10^{-2}\;\mu$m on the grain
size distribution. Consequently, the extinction curve at ultraviolet (UV)
wavelengths becomes steep, and a bump at $1/\lambda \sim 4.5\;\mu{\rm
m}^{-1}\;(\lambda: \mbox{wavelength})$ on the extinction curve becomes
prominent. Once coagulation becomes effective, the extinction curves become
flatter, but the UV extinction remains overproduced when compared with the
Milky Way extinction curve. This discrepancy can be resolved by introducing a
stronger contribution of coagulation. Consequently, an interplay between
shattering and coagulation could be important to reproduce the Milky Way
extinction curve.


title: Bounds for canonical Green's function at cusps

abstract:
  In this article, we derive bounds for the canonical Green's function defined
on a noncompact hyperbolic Riemann surface, when evaluated at two inequivalent
cusps.


title: Some Families of Identities for Integer Partition Function

abstract:
  We give a series of recursive identities for the number of partitions with
exactly $k$ parts and with constraints on both the minimal difference among the
parts and the minimal part. Using these results we demonstrate that the number
of partitions of $n$ is equal to the number of partitions of $2n+d{n \choose
2}$ with $n$ $d$-distant parts. We also provide a direct proof for this
identity. This work is the result of our aim at finding a bijective proof for
Rogers-Ramanujan identities.


title: Optimal search in interacting populations:Gaussian jumps vs Levy flights

abstract:
  We investigated the relationships between search efficiency, movement
strategy, and non-local communication in the biological context of animal
foraging. We considered situations where the members of a population of
foragers perform either Gaussian jumps or Levy flights, and show that the
search time is minimized when communication among individuals occurs at
intermediate ranges, independently of the type of movement. Additionally, while
Brownian strategies are more strongly influenced by the communication
mechanism, Levy flights still result in shorter overall search durations.


title: Early warning signs for saddle-escape transitions in complex networks

abstract:
  Many real world systems are at risk of undergoing critical transitions,
leading to sudden qualitative and sometimes irreversible regime shifts. The
development of early warning signals is recognized as a major challenge. Recent
progress builds on a mathematical framework in which a real-world system is
described by a low-dimensional equation system with a small number of key
variables, where the critical transition often corresponds to a bifurcation.
Here we show that in high-dimensional systems, containing many variables, we
frequently encounter an additional non-bifurcative saddle-type mechanism
leading to critical transitions. This generic class of transitions has been
missed in the search for early-warnings up to now. In fact, the saddle-type
mechanism also applies to low-dimensional systems with saddle-dynamics. Near a
saddle a system moves slowly and the state may be perceived as stable over
substantial time periods. We develop an early warning sign for the saddle-type
transition. We illustrate our results in two network models and epidemiological
data. This work thus establishes a connection from critical transitions to
networks and an early warning sign for a new type of critical transition. In
complex models and big data we anticipate that saddle-transitions will be
encountered frequently in the future.


title:
A relation of cusp forms and Maass forms on product of hyperbolic
  Riemann orbisurfaces of finite volume

abstract:
  In 2006, in a paper published in Compositio, titled "Bounds on canonical
Green's functions", J. Jorgenson and J. Kramer proved a certain key identity
which relates the two natural metrics, namely the hyperbolic metric and the
canonical metric defined on a compact hyperbolic Riemann surface. In this
article, we extend this identity to product of noncompact hyperbolic Riemann
orbisurfaces of finite volume, which can be realized as a quotient space of the
action of a Fuchsian subgroup of first kind on the hyperbolic upper half plane.


title:
Stabilisation de la formule des traces tordue II: int\'egrales orbitales
  et endoscopie sur un corps local non-archim\'edien; d\'efinitions et
  \'enonc\'es des r\'esultats

abstract:
  It is the second article of a series whose final goal is the stabilization of
the twisted trace formula. Over a non archimedean field, we define (after
Arthur) wheighted orbital integrals and their stable and endoscopic versions.
We state the main theorems that will be proved in the following articles. We
begin to study the local properties of our integrals, for instance expansion in
Shalika germs.


title: Low-energy trions in graphene quantum dots

abstract:
  We investigate, within the envelope function approximation, the low-energy
states of trions in graphene quantum dots. The presence of valley pseudospin in
graphene as an electron degree of freedom apart from spin adds convolution to
the interplay between exchange symmetry and the electron-electron interaction
in the trion, leading to new states of trions as well as a low energy trion
spectrum different from those in semiconductors. Due to the involvement of
valley pseudospin, it is found that the low-energy spectrum is nearly
degenerate and consists of states all characterized by having an antisymmetric
(pseudospin) (spin) component in the wave function, with the spin (pseudospin)
part being either singlet (triplet) or triplet (singlet), as opposed to the
spectrum in a semiconductor whose ground state is known to be nondegenerate and
always a spin singlet in the case of X- trions. We investigate trions in the
various regimes determined by the competition between quantum confinement and
electron-electron interaction, both analytically and numerically. The numerical
work is performed within a variational method accounting for electron mass
discontinuity across the QD edge. The result for electron-hole correlation in
the trion is presented. Effects of varying quantum dot size and confinement
potential strength on the trion binding energy are discussed.


title: Towards a Resolution of P = NP Conjecture

abstract:
  In this research paper, the problem of optimization of a quadratic form over
the convex hull generated by the corners of hypercube is attempted and solved.
It is reasoned that under some conditions, the optimum occurs at the corners of
hypercube. Results related to the computation of global optimum stable state
(an NP hard problem) are discussed. An algorithm is proposed. It is hoped that
the results shed light on resolving the P not equal to NP problem.


title: Absence of infinite cluster for critical Bernoulli percolation on slabs

abstract:
  We prove that for Bernoulli percolation on a graph
$\mathbb{Z}^2\times\{0,\dots,k\}$ ($k\ge 0$), there is no infinite cluster at
criticality, almost surely. The proof extends to finite range Bernoulli
percolation models on $\mathbb{Z}^2$ which are invariant under $\pi/2$-rotation
and reflection.


title:
Bounded Approximation Property for Sobolev spaces on simply-connected
  planar domains

abstract:
  We show that Sobolev space $W^1_1(\Omega)$ of any planar one-connected domain
$\Omega$ has the Bounded Approximation property. The result holds independently
from the properties of the boundary of $\Omega$. The prove is based on a new
decomposition of a planar domain.


title:
Self-gravitating system of semidegenerate fermions as central objects
  and dark matter halos in galaxies

abstract:
  We propose a unified model for dark matter haloes and central galactic
objects as a self-gravitating system of semidegenerated fermions in thermal
equilibrium. We consider spherical symmetry and then we solve the equations of
gravitational equilibrium using the Fermi integrals in a dimensionless manner,
obtaining the density profile and velocity curve. We also obtain scaling laws
for the observables of the system and show that, for a wide range of our
parameters, our model is consistent with the so called universality of the
surface density of dark matter.


title: A Dynamical Mean-field Study of LaNiO$_3$

abstract:
  While most of the rare-earth nickelates exhibit a temperature-driven sharp
metal-insulator transition, LaNiO$_3$ is the only exception remaining metallic
down to low temperatures. Using local density approximation as an input to
dynamical mean-field calculation, metallic properties of bulk LaNiO$_{3}$ is
studied. The DMFT calculations indicate that the system is a correlated Fermi
liquid with an enhanced effective mass. The possibility of a pressure-driven
metal-insulator transition in the system is also suggested, which can be
verified experimentally.


title: Block-Fading Channels with Delayed CSIT at Finite Blocklength

abstract:
  In many wireless systems, the channel state information at the transmitter
(CSIT) can not be learned until after a transmission has taken place and is
thereby outdated. In this paper, we study the benefits of delayed CSIT on a
block-fading channel at finite blocklength. First, the achievable rates of a
family of codes that allows the number of codewords to expand during
transmission, based on delayed CSIT, are characterized. A fixed-length and a
variable-length characterization of the rates are provided using the dependency
testing bound and the variable-length setting introduced by Polyanskiy et al.
Next, a communication protocol based on codes with expandable message space is
put forth, and numerically, it is shown that higher rates are achievable
compared to coding strategies that do not benefit from delayed CSIT.


title: Further Results on Homogeneous Two-Weight Codes

abstract:
  The results of [1,2] on linear homogeneous two-weight codes over finite
Frobenius rings are exended in two ways: It is shown that certain
non-projective two-weight codes give rise to strongly regular graphs in the way
described in [1,2]. Secondly, these codes are used to define a dual two-weight
code and strongly regular graph similar to the classical case of projective
linear two-weight codes over finite fields [3].


title: A falsely fat curvaton with an observable running of the spectral tilt

abstract:
  In slow roll inflation, the running of the spectral tilt is generically
proportional to the square of the deviation from scale invariance, $\alpha_s
\propto (n_s-1)^2$, and it is therefore currently undetectable. We present a
mechanism able to generate a much larger running within slow roll. The
mechanism is based on a curvaton field with a large mass term, and a time
evolving normalization. This may happen for instance to the angular direction
of a complex field in presence of an evolving radial direction. At the price of
a single tuning between the mass term and the rate of change of the
normalization, the curvaton can be made effectively light at the CMB scales,
giving a spectral tilt in agreement with observations. The lightness is not
preserved at later times, resulting in a detectable running of the spectral
tilt. This mechanism shows that fields with a large mass term do not
necessarily decouple from the inflationary physics, and provides a new tool for
model building in inflation.


title:
A variational polaron self-interaction corrected total-energy functional
  for charge excitations in wide-band gap insulators

abstract:
  We conduct a detailed investigation of the polaron self-interaction (pSI)
error in standard approximations to the exchange-correlation (XC) functional
within density-functional theory (DFT). The pSI leads to delocalization error
in the polaron wave function and energy, as calculated from the Kohn-Sham (KS)
potential in the native charge state of the polaron. This constitutes the
origin of the systematic failure of DFT to describe polaron formation in band
insulators. It is shown that the delocalization error in these systems is,
however, largely absent in the KS potential of the closed-shell neutral charge
state. This leads to a modification of the DFT total-energy functional that
corrects the pSI in the XC functional. The resulting pSIC-DFT method
constitutes an accurate parameter-free {\it ab initio} methodology for
calculating polaron properties in insulators at a computational cost that is
orders of magnitude smaller than hybrid XC functionals. Unlike approaches that
rely on parametrized localized potentials such as DFT+$U$, the pSIC-DFT method
properly captures both site and bond-centered polaron configurations. This is
demonstrated by studying formation and migration of self-trapped holes in
alkali halides (bond-centered) as well as self-trapped electrons in an
elpasolite compound (site-centered). The pSIC-DFT approach consistently
reproduces the results obtained by hybrid XC functionals parametrized by
DFT+$G_0W_0$ calculations. Finally, we generalize the pSIC approach to hybrid
functionals, and show that in stark contrast to conventional hybrid
calculations of polaron energies, the pSIC-hybrid method is insensitive to the
parametrization of the hybrid XC functional. On this basis, we further
rationalize the success of the pSIC-DFT approach.


title: Synchrotron Polarization in Blazars

abstract:
  We present a detailed analysis of time- and energy-dependent synchrotron
polarization signatures in a shock-in-jet model for gamma-ray blazars. Our
calculations employ a full 3D radiation transfer code, assuming a helical
magnetic field throughout the jet. The code considers synchrotron emission from
an ordered magnetic field, and takes into account all light-travel-time and
other relevant geometric effects, while the relevant synchrotron self-Compton
and external Compton effects are taken care of with the 2D MCFP code. We
consider several possible mechanisms through which a relativistic shock
propagating through the jet may affect the jet plasma to produce a synchrotron
and high-energy flare. Most plausibly, the shock is expected to lead to a
compression of the magnetic field, increasing the toroidal field component and
thereby changing the direction of the magnetic field in the region affected by
the shock. We find that such a scenario leads to correlated synchrotron + SSC
flaring, associated with substantial variability in the synchrotron
polarization percentage and position angle. Most importantly, this scenario
naturally explains large PA rotations by > 180 deg., as observed in connection
with gamma-ray flares in several blazars, without the need for bent or helical
jet trajectories or other non-axisymmetric jet features.


title: On the Kac model for the Landau equation

abstract:
  We introduce a N-particle system which approaches, in the mean-field limit,
the solutions of the Landau equation with Coulomb singularity. This model plays
the same role as the Kac's model for the homogeneous Boltzmann equation.


title: Electrodynamics in Skyrmions Merging

abstract:
  In a recent study the coalescence of magnetic skyrmions was observed in a
metallic chiral magnet Fe0.5Co0.5Si when the skyrmion phase is destroyed, and
numerical simulations demonstrated the existence of a monopole at the merging
point of two skyrmion lines. The exchange interaction between such magnetic
textures and the conduction electrons can be described by emergent
electromagnetism. In this paper, we investigate the effect of a
skyrmions-merging process on conduction electrons by calculating induced
electric currents. Here, in addition to the exchange interactions, we consider
the antisymmetric spin-orbit couplings (SOC) due to broken inversion symmetry,
which is an essential ingredient for the realization of skyrmion texture in the
itinerant magnet Fe0.5Co0.5Si. We obtain an adiabatic current which is
dissipationless, and dissipative currents driven by the effective
electromagnetic fields including the effect of SOC. In terms of the effective
fields, a moving monopole at the merging point turns out to be a dyon-like
object; i.e. it has both electric charge and magnetic charge.


title:
Adaptive Power Management for Wireless Base Station in Smart Grid
  Environment

abstract:
  The growing concerns of a global environmental change raises a revolution on
the way of utilizing energy. In wireless industry, green wireless
communications has recently gained increasing attention and is expected to play
a major role in reduction of electrical power consumption. In particular,
actions to promote energy saving of wireless communications with regard to
environmental protection are becoming imperative. To this purpose, we study a
green communication system model where wireless base station is provisioned
with a combination of renewable power source and electrical grid to minimize
power consumption as well as meeting the users' demand. More specifically, we
focus on an adaptive power management for wireless base station to minimize
power consumption under various uncertainties including renewable power
generation, power price, and wireless traffic load. We believe that demand side
power management solution based on the studied communication architecture is a
major step towards green wireless communications.


title:
Bound states of spatially dependent mass Dirac equation with the Eckart
  potential including Coulomb tensor interaction

abstract:
  We investigate the approximate solutions of the Dirac equation with the
position-dependent mass particle in the Eckart potential field including the
Coulomb tensor interaction by using the parametric Nikiforov-Uvarov method.
Taking an appropriate approximation to deal with the centrifugal term, the
Dirac energy states and the corresponding normalized two-spinor components of
the wave function are obtained in closed form. Some special cases of our
solution are investigated. Furthermore, we present the correct solutions
obtained via the asymptotic iteration method which are in agreement with the
parametric Nikiforov-Uvarov method results.


title:
Woronowicz construction of compact quantum groups for functions on
  permutations. Classification result for N=3

abstract:
  We provide a classification of compact quantum groups, which can be obtained
by the Woronowicz construction, when the arrays used in the twisted determinant
condition are extensions of functions on permutations. General properties of
such quantum groups are revealed with the aid of operators intertwining tensor
powers of the fundamental corepresentation. Two new families of quantum groups
appear: three versions of the quantum group $SU_q(3)$ with complex $q$ and a
non-commutative analogue of the semi-direct product of two-dimensional torus
with the alternating group $A_3$.


title: Dirac bound states of anharmonic oscillator in external fields

abstract:
  We explore the effect of the external magnetic and Aharonov-Bohm (AB) flux
fields on the energy levels of Dirac particle subjects to mixed scalar and
vector anharmonic oscillator field in the two-dimensional (2D) space. We
calculate the exact energy eigenvalues and the corresponding un-normalized
two-spinor-components wave functions in terms of the chemical potential
parameter, magnetic field strength, AB flux field and magnetic quantum number
by using the Nikiforov-Uvarov (NU) method.


title: Tempering by Subsampling

abstract:
  In this paper we demonstrate that tempering Markov chain Monte Carlo samplers
for Bayesian models by recursively subsampling observations without replacement
can improve the performance of baseline samplers in terms of effective sample
size per computation. We present two tempering by subsampling algorithms,
subsampled parallel tempering and subsampled tempered transitions. We provide
an asymptotic analysis of the computational cost of tempering by subsampling,
verify that tempering by subsampling costs less than traditional tempering, and
demonstrate both algorithms on Bayesian approaches to learning the mean of a
high dimensional multivariate Normal and estimating Gaussian process
hyperparameters.


title: SSthreshless Start: A Sender-Side TCP Intelligence for Long Fat Network

abstract:
  Measurement shows that 85% of TCP flows in the internet are short-lived flows
that stay most of their operation in the TCP startup phase. However, many
previous studies indicate that the traditional TCP Slow Start algorithm does
not perform well, especially in long fat networks. Two obvious problems are
known to impact the Slow Start performance, which are the blind initial setting
of the Slow Start threshold and the aggressive increase of the probing rate
during the startup phase regardless of the buffer sizes along the path. Current
efforts focusing on tuning the Slow Start threshold and/or probing rate during
the startup phase have not been considered very effective, which has prompted
an investigation with a different approach. In this paper, we present a novel
TCP startup method, called threshold-less slow start or SSthreshless Start,
which does not need the Slow Start threshold to operate. Instead, SSthreshless
Start uses the backlog status at bottleneck buffer to adaptively adjust probing
rate which allows better seizing of the available bandwidth. Comparing to the
traditional and other major modified startup methods, our simulation results
show that SSthreshless Start achieves significant performance improvement
during the startup phase. Moreover, SSthreshless Start scales well with a wide
range of buffer size, propagation delay and network bandwidth. Besides, it
shows excellent friendliness when operating simultaneously with the currently
popular TCP NewReno connections.


title:
XMM-Newton reveals a candidate period for the spin of the "Magnificent
  Seven" neutron star RX J1605.3+3249

abstract:
  The group of thermally emitting isolated neutron stars (INSs) known as the
"Magnificent Seven" (M7) is unique among the various neutron star populations.
Crustal heating by means of magnetic field decay and an evolutionary link with
magnetars may explain why these objects rotate more slowly and have higher
thermal luminosities and magnetic field intensities than standard pulsars of
similar age. The third brightest INS, RX J1605.3+3249, is the only object
amidst the seven still lacking a detected periodicity. We observed the source
with the XMM-Newton Observatory for 60 ks aiming at unveiling the neutron star
rotation rate and investigating its spectrum in detail. A periodic signal at
P=3.387864(16) s, most likely the neutron star spin period, is detected at the
4-sigma confidence level. The coherent combination of the new data with a past
XMM-Newton EPIC-pn observation of the source constrains the pulsar spin-down
rate at the 2-sigma confidence level, implying a dipolar magnetic field of
B~7.4e13 G. If confirmed, RX J1605.3+3249 would be the neutron star with the
highest dipolar field amongst the M7. The spectrum of the source shows evidence
of a cool blackbody component, as well as for the presence of two broad
absorption features. Furthermore, high-resolution spectroscopy with the RGS
cameras confirms the presence of a narrow absorption feature at energy 0.57 keV
in the co-added spectrum of the source, also seen in other thermally emitting
isolated neutron stars. Phase-resolved spectroscopy, as well as a dedicated
observing campaign aimed at determining a timing solution, will give invaluable
constraints on the neutron star geometry and will allow one to confirm the high
value of spin down, which would place the source closer to a magnetar than any
other M7 INS.


title: A Software Design through Electrical System for a Building

abstract:
  Computer aided design of lighting systems made new installations of lighting
dimensioning and verification of existing lighting systems for both indoor and
outdoor lighting systems.The design of the building light system was in a
dedicated software, named DiaLux, version 4.11.


title:
Soft-photon exponentiation beyond the quenched approximation in
  QED$_{2+1}$

abstract:
  We discuss the infrared and ultraviolet behavior of the fermion propagator in
(2+1)-dimensional QED based on spectral representation.If we choose soft-photon
exponentiation to include all orders of soft-photon emission by electron,its
spectral function may be written as $e^{F}$,where $F$ is a model independent
spectral function of the lowest order in the coupling constant.We evaluate the
function $F$ in an analytic way and show its short and long distance behavior
with an infrared cut-off $\mu$.At short distance function $F$ has linear and
logarithmic infrared divergence.However in the long distance limit function $F$
vanishes.So that only short distance part of $e^{F}$ is modified from unity.We
may avoid the linear divergence by the choice of the gauge $d=-1$,where $d$ is
a covariant gauge fixing parameter.In this gauge the spectral function vanishes
in the limit of zero bare photon mass $\mu$.We overcome this difficulty by
adding continuous spectrum of massive fermion loop to photon spectral function
$\rho(\mu^{2})$,where $\mu$ has the role of invariant mass for
fermion-antifermion pair and is larger than $2m.$So that unquenched fermion
spectral function survibes.For the application of chiral symmetry breaking we
carefully studied the position space propagator $S_{F}(0)$.At least for weak
coupling these values agree quite well with that obtained in Dyson-Schwinger
equation with proper vertex correction.We also study these parameter as a
function of the flavour number $N$ and t'Hooft coupling $\alpha=e^{2}N/8\pi$
for strong coupling case.


title: Profinite and discrete G-spectra and iterated homotopy fixed points

abstract:
  For a profinite group $G$, let $(\text{-})^{hG}$, $(\text{-})^{h_dG}$, and
$(\text{-})^{h'G}$ denote continuous homotopy fixed points for profinite
$G$-spectra, discrete $G$-spectra, and continuous $G$-spectra (coming from
towers of discrete $G$-spectra), respectively. We establish some connections
between the first two notions, and by using Postnikov towers, for $K
\vartriangleleft_c G$ (a closed normal subgroup), give various conditions for
when the iterated homotopy fixed points $(X^{hK})^{hG/K}$ exist and are
$X^{hG}$. For the Lubin-Tate spectrum $E_n$ and $G <_c G_n$, the extended
Morava stabilizer group, our results show that $E_n^{hK}$ is a profinite
$G/K$-spectrum with $(E_n^{hK})^{hG/K} \simeq E_n^{hG}$, by an argument that
possesses a certain technical simplicity not enjoyed by either the proof that
$(E_n^{h'K})^{h'G/K} \simeq E_n^{h'G}$ or the Devinatz-Hopkins proof (which
requires $|G/K| < \infty$) of $(E_n^{dhK})^{h_dG/K} \simeq E_n^{dhG}$, where
$E_n^{dhK}$ is a construction that behaves like continuous homotopy fixed
points. Also, we prove that (in general) the $G/K$-homotopy fixed point
spectral sequence for $\pi_\ast((E_n^{hK})^{hG/K})$, with $E_2^{s,t} =
H^s_c(G/K; \pi_t(E_n^{hK}))$ (continuous cohomology), is isomorphic to both the
strongly convergent Lyndon-Hochschild-Serre spectral sequence of Devinatz for
$\pi_\ast(E_n^{dhG})$, with $E_2^{s,t} = H^s_c(G/K; \pi_t(E_n^{dhK}))$, and the
descent spectral sequence for $\pi_\ast((E_n^{h'K})^{h'G/K})$.


title: Continuous Fields of Postliminal C*-algebras

abstract:
  We discuss a problem of Dixmier on continuous fields of postliminal
C*-algebras and the greatest liminal ideals of the fibers.


title: Mean value estimates for odd cubic Weyl sums

abstract:
  We establish an essentially optimal estimate for the ninth moment of the
exponential sum having argument $\alpha x^3+\beta x$. The first substantial
advance in this topic for over 60 years, this leads to improvements in
Heath-Brown's variant of Weyl's inequality, and other applications of
Diophantine type.


title: Light Z' in Heterotic String Standard-like Models

abstract:
  The discovery of the Higgs boson at the LHC supports the hypothesis that the
Standard Model provides an effective parameterisation of all subatomic
experimental data up to the Planck scale. String theory, which provides a
viable perturbative approach to quantum gravity, requires for its consistency
the existence of additional gauge symmetries beyond the Standard Model. The
construction of heterotic--string models with a viable light $Z^\prime$ is,
however, highly constrained. We outline the construction of standard--like
heterotic--string models that allow for an additional Abelian gauge symmetry
that may remain unbroken down to low scales. We present a string inspired
model, consistent with the string constraints.