title: Unknotting rectangular diagrams of the trivial knot by exchanging moves

abstract:
  If a rectangular diagram represents the trivial knot, then it can be deformed
into the rectangular diagram with only two vertical edges by a finite sequence
of merge operations and exchange operations, without increasing the number of
vertical edges, which was shown by I. A. Dynnikov.
  We show in this paper that we need no merge operations to deform a
rectangular diagram of the trivial knot to one with no crossings.


title:
Constraints of relic gravitational waves by Pulsar Timing Array:
  Forecasts for the FAST and SKA projects

abstract:
  Measurement of the pulsar timing residuals provides a direct way to detect
relic gravitational waves at the frequency $f\sim 1/{\rm yr}$. In this paper,
we investigate the constraints on the inflationary parameters, the
tensor-to-scalar ratio $r$ and the tensor spectral index $n_t$, by the current
and future Pulsar Timing Arrays (PTAs). We find that Five-hundred-meter
Aperture Spherical radio Telescope (FAST) in China and the planned Square
Kilometer Array (SKA) projects have the fairly strong abilities to test the
phantom-like inflationary models. If $r=0.1$, FAST could give the constraint on
the spectral index $n_t<0.56$, and SKA gives $n_t<0.32$. While an observation
with the total time T=20 yr, the pulsar noise level $\sigma_w=30$ns and the
monitored pulsar number $n=200$, could even constrain $n_t<0.07$. These are
much tighter than those inferred from the current results of Parkers Pulsar
Timing Array (PPTA), European Pulsar Timing Array (EPTA) and North American
Nanohertz Observatory for Gravitational waves (NANOGrav). Especially, by
studying the effects of various observational factors on the sensitivities of
PTAs, we found that compared with $\sigma_w$ and $n$, the total observation
time $T$ has the most significant effect.


title: Blind Identification of ARX Models with Piecewise Constant Inputs

abstract:
  Blind system identification is known to be a hard ill-posed problem and
without further assumptions, no unique solution is at hand. In this
contribution, we are concerned with the task of identifying an ARX model from
only output measurements. Driven by the task of identifying systems that are
turned on and off at unknown times, we seek a piecewise constant input and a
corresponding ARX model which approximates the measured outputs. We phrase this
as a rank minimization problem and present a relaxed convex formulation to
approximate its solution. The proposed method was developed to model power
consumption of electrical appliances and is now a part of a bigger energy
disaggregation framework. Code will be made available online.


title:
Implications of a matter-radius measurement for the structure of
  Carbon-22

abstract:
  We study Borromean 2n-halo nuclei using effective field theory. We compute
the universal scaling function that relates the mean-square matter radius of
the 2n halo to dimensionless ratios of two- and three-body energies. We use the
experimental value of the rms matter radius of 22C measured by Tanaka et al. to
put constraints on its 2n separation energy and the 20C-n virtual energy. We
also explore the consequences of these constraints for the existence of excited
Efimov states in this nucleus. We find that, for 22C to have an rms matter
radius within 1-sigma of the experimental value, the two-neutron separation
energy of 22C needs to be below 100 keV. Consequently, this three-body halo
system can have an excited Efimov state only if the 20C-n system has a
resonance within 1 keV of the scattering threshold.


title: Global bifurcation for the Whitham equation

abstract:
  We prove the existence of a global bifurcation branch of $2\pi$-periodic,
smooth, traveling-wave solutions of the Whitham equation. It is shown that any
subset of solutions in the global branch contains a sequence which converges
uniformly to some solution of H\"older class $C^{\alpha}$, $\alpha <
\frac{1}{2}$. Bifurcation formulas are given, as well as some properties along
the global bifurcation branch. In addition, a spectral scheme for computing
approximations to those waves is put forward, and several numerical results
along the global bifurcation branch are presented, including the presence of a
turning point and a `highest', cusped wave. Both analytic and numerical results
are compared to traveling-wave solutions of the KdV equation.


title:
Temporal Variations of High-Degree Solar p-Modes using Ring-Diagram
  Analysis

abstract:
  We study temporal variations in the amplitudes and widths of high-degree
acoustic modes by applying the ring-diagram technique to the GONG+, MDI and HMI
Dopplergrams during the declining phase of cycle 23 and rising phase of cycle
24. The mode parameters from all three instruments respond similarly to the
varying magnetic activity. The mode amplitudes and widths show consistently
lower variation due to smaller magnetic activity in cycle 24 as compared to the
previous solar cycle.


title:
Spontaneous nucleation and dynamics of kink defects in zigzag arrays of
  trapped ions

abstract:
  The spontaneous nucleation and dynamics of topological kink defects have been
studied in trapped arrays of 41-43 Yb ions. The number of kinks formed as a
function of quench rate across the linear-zigzag transition is measured in the
under-damped regime of the inhomogeneous Kibble-Zurek theory. The experimental
results agree well with molecular dynamics simulations, which show how losses
mask the intrinsic nucleation rate. Simulations indicate that doubling the ion
number and optimization of laser cooling can help reduce the effect of losses.
A range of kink dynamics is observed including configural change, motion and
lifetime, and behavioral sensitivity to ion number.


title: Steady-state fingering patterns for a periodic Muskat problem

abstract:
  We study global bifurcation branches consisting of stationary solutions of
the Muskat problem. It is proved that the steady-state fingering patterns blow
up as the surface tension increases: we find a threshold value for the cell
height with the property that below this value the fingers will touch the
boundaries of the cell when the surface tension approaches a finite value from
below; otherwise, the maximal slope of the fingers tends to infinity.


title:
HerMES: A Deficit in the Surface Brightness of the Cosmic Infrared
  Background Due to Galaxy Cluster Gravitational Lensing

abstract:
  We have observed four massive galaxy clusters with the SPIRE instrument on
the Herschel Space Observatory and measure a deficit of surface brightness
within their central region after subtracting sources. We simulate the effects
of instrumental sensitivity and resolution, the source population, and the
lensing effect of the clusters to estimate the shape and amplitude of the
deficit. The amplitude of the central deficit is a strong function of the
surface density and flux distribution of the background sources. We find that
for the current best fitting faint end number counts, and excellent lensing
models, the most likely amplitude of the central deficit is the full intensity
of the cosmic infrared background (CIB). Our measurement leads to a lower limit
to the integrated total intensity of the CIB of I(250 microns) >
0.69_(-0.03)^(+0.03) (stat.)_(-0.06)^(+0.11) (sys.) MJy/sr, with more CIB
possible from both low-redshift sources and from sources within the target
clusters. It should be possible to observe this effect in existing high angular
resolution data at other wavelengths where the CIB is bright, which would allow
tests of models of the faint source component of the CIB.


title: Towards New Classes of Flux Compactifications

abstract:
  We derive novel solutions of flux compactification with D7-branes on the
resolved conifold in type IIB String Theory and later extend this solution to
allow for non-zero temperature. At zero temperature, we find that adding
D7-branes via the Ouyang embedding contributes to the supersymmetry-breaking
(1,2) imaginary-self-dual flux, without generating a bulk cosmological
constant. We further find that having D7-branes and a resolved conifold
together give rise to a non-trivial D-term on the D7-branes. This
supersymmetry-breaking term vanishes when we take the singular conifold limit,
although supersymmetry appears to remain broken. We also lift our construction
to F-theory where we show that the type IIB (1,2) flux goes to (2,2)
non-primitive flux on the fourfold.
  In the second part of the thesis, we extend these results by taking the
non-extremal limit of our geometry to incorporate temperature. In this case,
the internal NS-NS and R-R fluxes are no longer expected to be self-dual, but
they should also naturally be extensions of the fluxes found above. From the
supergravity equations of motion, we compute how the new contributions to the
fluxes should enter, due to the squashing of the resolved metric and
non-extremality. This provides us with a compelling gravity dual of large N
thermal quantum chromodynamics with flavor.


title: The O_{D,D} Geometry of String Theory

abstract:
  We construct an action for double field theory using a metric connection that
is compatible with both the generalised metric and the O_{D,D} structure. The
connection is simultaneously torsionful and flat. Using this connection one may
construct a proper covariant derivative for double field theory. We then write
the doubled action in terms of the generalised torsion of this connection. This
action then exactly reproduces that required for doubled field theory and
gauged supergravity.


title:
Instantons in G2 manifolds from J-holomorphic curves in coassociative
  submanifolds

abstract:
  In G2 manifolds, 3-dimensional associative submanifolds (instantons) play a
role similar to J-holomorphic curves in symplectic geometry. In [21],
instantons in G2 manifolds were constructed from regular J-holomorphic curves
in coassociative submanifolds. In this exposition paper, after reviewing the
background of G2 geometry, we explain the main ingredients in the proofs in
[21]. We also construct new examples of instantons.


title: Matchgates Revisited

abstract:
  We study a collection of concepts and theorems that laid the foundation of
matchgate computation. This includes the signature theory of planar matchgates,
and the parallel theory of characters of not necessarily planar matchgates. Our
aim is to present a unified and, whenever possible, simplified account of this
challenging theory. Our results include: (1) A direct proof that Matchgate
Identities (MGI) are necessary and sufficient conditions for matchgate
signatures. This proof is self-contained and does not go through the character
theory. More importantly it rectifies a gap in the existing proof. (2) A proof
that Matchgate Identities already imply the Parity Condition. (3) A simplified
construction of a crossover gadget. This is used in the proof of sufficiency of
MGI for matchgate signatures. This is also used to give a proof of equivalence
between the signature theory and the character theory which permits omittable
nodes. (4) A direct construction of matchgates realizing all
matchgate-realizable symmetric signatures.


title:
Fluorescence thermometry enhanced by the quantum coherence of single
  spins in diamond

abstract:
  We demonstrate fluorescence thermometry techniques with sensitivities
approaching 10 mK Hz^(-1/2) based on the spin-dependent photoluminescence of
nitrogen vacancy (NV) centers in diamond. These techniques use dynamical
decoupling protocols to convert thermally induced shifts in the NV center's
spin resonance frequencies into large changes in its fluorescence. By
mitigating interactions with nearby nuclear spins and facilitating selective
thermal measurements, these protocols enhance the spin coherence times
accessible for thermometry by 45x, corresponding to a 7x improvement in the NV
center's temperature sensitivity. Moreover, we demonstrate these techniques can
be applied over a broad temperature range and in both finite and near-zero
magnetic field environments. This versatility suggests that the quantum
coherence of single spins could be practically leveraged for sensitive
thermometry in a wide variety of biological and microscale systems.


title: Low beta spoke cavity multipacting analysis

abstract:
  The simulation and analysis for electron multipacting phenomenon in low
{\beta} spoke superconducting cavity in ADS proton accelerator are proposed.
Using both CST and Track3P codes, the electron multipacting calculation for
{\beta} = 0.12 spoke superconducting cavity is implemented. The methods of
multipacting calculation on both codes are studied and described. With the
comparison between the calculation results and the cavity vertical test
results, the accuracy and reliability of different code on calculating
multipacting are analyzed. Multipacting calculation can help to understand the
result of vertical test and also can help to do the optimation in cavity
design.


title:
Target duality in N=8 superconformal mechanics and the coupling of dual
  pairs

abstract:
  We couple dual pairs of N=8 superconformal mechanics with conical targets of
dimension d and 8-d. The superconformal coupling generates an oscillator-type
potential on each of the two target factors, with a frequency depending on the
respective dual coordinates. In the case of the inhomogeneous (3,8,5) model,
which entails a monopole background, it is necessary to add an extra
supermultiplet of constants for half of the supersymmetry. The N=4 analog,
joining an inhomogeneous (1,4,3) with a (3,4,1) multiplet, is also analyzed in
detail.


title:
Unambiguous Determination of the Neutrino Mass Hierarchy Using Reactor
  Neutrinos

abstract:
  Determination of the neutrino mass hierarchy in a reactor neutrino experiment
at medium baseline is discussed. Observation of the interference effects
between the \Delta m^2_{31} and \Delta m^2_{32} oscillations enables a relative
measurement independent of the knowledge of the absolute mass-squared
difference. With a 20 kton liquid scintillator detector of 3%/\sqrt{E(MeV)}
energy resolution, the Daya Bay II Experiment at a baseline of \sim 50 km from
reactors of total thermal power 36 GW can determine the mass hierarchy at a
confidence level of \Delta \chi^2_{MH} \sim (10-12) (3-3.5 \sigma) in 6 years
after taking into account the real spatial distribution of reactor cores. We
show that the unknown residual energy non-linearity of the liquid scintillator
detector has limited impact on the sensitivity due to the self-calibration of
small oscillation peaks. Furthermore, an extra increase of \Delta \chi^2_{MH}
\simeq 4(9) can be obtained, by including the precise measurement of the
effective mass-squared difference \Delta m^2_{\mu\mu} of expected relative
error 1.5% (1%) from ongoing long-baseline muon neutrino disappearance
experiments. The sensitivities from the interference and from absolute
measurements can be cross checked. When combining these two, the mass hierarchy
can be determined at a confidence level of \Delta \chi^2_{MH} \sim (15-20) (4
\sigma) in 6 years.


title:
Simulation studies on laser pulse stability for Dalian Coherent Light
  Source

abstract:
  Dalian Coherent Light Source will use a 300MeV LINAC to produce fully
coherent photon pulses in the wavelength range between 150-50nm by high gain
harmonic generation free electron laser (FEL) scheme. To generate stable FEL
pulses, stringent tolerance budget is required for the LINAC output parameters,
such as the mean beam energy stability, electron bunch arrival time jitter,
peak current variation and the transverse beam position offset. In order to
provide guidance for the design of the Dalian Coherent Light Source, in this
paper, the sensitivity of FEL pulse energy fluctuation to various error sources
of the electron bunch was performed using intensive start-to-end FEL
simulations.


title: Coupling strength of the $N^*(1535)S_{11}$ to the $K^+\Lambda$ channel

abstract:
  The $N^*(1535)S_{11}$ coupling strength to the $K^+\Lambda$ channel,
$g_{N^*(1535)\Lambda K^+}$, is extracted from the latest and largest
$K^+\Lambda$ photoproduction database by using an isobar model. It is found
that the coupling is small. In term of the coupling ratio the best result is
$R\equiv |g_{N^*(1535)\Lambda K^+}/g_{N^*(1535)\eta p}|=0.460\pm 0.172$, much
smaller than that obtained from the isobar analysis of the $J/\psi$ decays,
i.e., $1.3\pm 0.3$, but consistent with the results of the unitary chiral
approach of the same decay processes as well as the partial wave analysis of
kaon photoproduction, i.e., $R=0.5\sim 0.7$. The different results of $R$ found
here and in literature to date suggest that a more solid definition of the
coupling constant, especially in the case of $N^*(1535)S_{11}$ state, is
urgently required, before a fair comparison can be made.


title:
A Mechanism of Exciting Planetary Inclination and Eccentricity through a
  Residual Gas Disk

abstract:
  Accordling to the theory of Kozai resonance, the initial mutual inclination
between a small body and a massive planet in an outer circular orbit is as high
as $\sim39.2^{\circ}$ for pumping the eccentricity of the inner small body.
Here we show that, with the presence of a residual gas disk outside two
planetary orbits, the inclination can be reduced as low as a few degrees. The
presence of disk changes the nodal precession rates and directions of the
planet orbits. At the place where the two planets achieve the same nodal
processing rate, vertical secular resonance would occur so that mutual
inclination of the two planets will be excited, which might trigger the Kozai
resonance between the two planets further. However, in order to pump an inner
Jupiter-like planet, the conditions required for the disk and the outer planet
are relatively strict. We develop a set of evolution equations, which can fit
the N-body simulation quite well but be integrated within a much shorter time.
By scanning the parameter spaces using the evolution equations, we find that, a
massive planet ($10M_J$) at 30AU with $6^o$ inclined to a massive disk
($50M_J$) can finally enter the Kozai resonance with an inner Jupiter around
the snowline. And a $20^{\circ}$ inclination of the outer planet is required
for flipping the inner one to a retrograde orbit. In multiple planet systems,
the mechanism can happen between two nonadjacent planets, or inspire a chain
reaction among more than two planets. This mechanism could be the source of the
observed giant planets in moderate eccentric and inclined orbits, or
hot-Jupiters in close-in, retrograde orbits after tidal damping.


title: Simplifying Biochemical Models With Intermediate Species

abstract:
  Mathematical models are increasingly being used to understand complex
biochemical systems, to analyze experimental data and make predictions about
unobserved quantities. However, we rarely know how robust our conclusions are
with respect to the choice and uncertainties of the model. Using algebraic
techniques we study systematically the effects of intermediate, or transient,
species in biochemical systems and provide a simple, yet rigorous mathematical
classification of all models obtained from a core model by including
intermediates. Main examples include enzymatic and post-translational
modification systems, where intermediates often are considered insignificant
and neglected in a model, or they are not included because we are unaware of
their existence. All possible models obtained from the core model are
classified into a finite number of classes. Each class is defined by a
mathematically simple canonical model that characterizes crucial dynamical
properties, such as mono- and multistationarity and stability of steady states,
of all models in the class. We show that if the core model does not have
conservation laws, then the introduction of intermediates does not change the
steady-state concentrations of the species in the core model, after suitable
matching of parameters. Importantly, our results provide guidelines to the
modeler in choosing between models and in distinguishing their properties.
Further, our work provides a formal way of comparing models that share a common
skeleton.


title:
Parameter Space Compression Underlies Emergent Theories and Predictive
  Models

abstract:
  We report a similarity between the microscopic parameter dependance of
emergent theories in physics and that of multiparameter models common in other
areas of science. In both cases, predictions are possible despite large
uncertainties in the microscopic parameters because these details are
compressed into just a few governing parameters that are sufficient to describe
relevant observables. We make this commonality explicit by examining parameter
sensitivity in a hopping model of diffusion and a generalized Ising model of
ferromagnetism. We trace the emergence of a smaller effective model to the
development of a hierarchy of parameter importance quantified by the
eigenvalues of the Fisher Information Matrix. Strikingly, the same hierarchy
appears ubiquitously in models taken from diverse areas of science. We conclude
that the emergence of effective continuum and universal theories in physics is
due to the same parameter space hierarchy that underlies predictive modeling in
other areas of science.

categories: cond-mat.stat-mech math-ph math.MP physics.data-an q-bio.OT


title: The "Wow! signal" of the terrestrial genetic code

abstract:
  It has been repeatedly proposed to expand the scope for SETI, and one of the
suggested alternatives to radio is the biological media. Genomic DNA is already
used on Earth to store non-biological information. Though smaller in capacity,
but stronger in noise immunity is the genetic code. The code is a flexible
mapping between codons and amino acids, and this flexibility allows modifying
the code artificially. But once fixed, the code might stay unchanged over
cosmological timescales. Thus, it represents a reliable storage for an
intelligent signature, if that conforms to biological and thermodynamic
requirements. As the actual scenario for the origin of terrestrial life is far
from being settled, the proposal that it might have been seeded intentionally
cannot be ruled out. A statistically strong signal in the genetic code is then
a testable consequence of such scenario. Here we show that the terrestrial code
displays a thorough precision orderliness matching the criteria to be
considered an informational signal. Simple arrangements of the code reveal an
ensemble of arithmetical and ideographical patterns of the same symbolic
language. Accurate and systematic, these underlying patterns appear as a
product of precision logic and nontrivial computing rather than of stochastic
processes. The patterns are profound to the extent that the code mapping itself
is uniquely deduced from their algebraic representation. The signal displays
readily recognizable hallmarks of artificiality. Besides, extraction of the
signal involves logically straightforward but abstract operations, making the
patterns essentially irreducible to any natural origin. Plausible way of
embedding the signal into the code and possible interpretation of its content
are discussed. Overall, while the code is nearly optimized biologically, its
limited capacity is used extremely efficiently to store non-biological
information.


title: Multi-setting Greenberger-Horne-Zeilinger Paradoxes

abstract:
  Greenberger-Horne-Zeilinger (GHZ) paradox provides an all-versus-nothing test
for the quantum nonlocality. In all the GHZ paradoxes known so far each
observer is allowed to measure only two alternative observables. Here we shall
present a general construction for GHZ paradoxes in which each observer
measuring more than two observables given that the system is prepared in the
$n$-qudit GHZ state. By doing so we are able to construct a multi-setting GHZ
paradox for the $n$-qubit GHZ state, with $n$ being arbitrary, that is genuine
$n$-partite, i.e., no GHZ paradox exists when restrict to a subset of number of
observers for a given set of Mermin observables. Our result fills up the gap of
the absence of a genuine GHZ paradox for the GHZ state of an even number of
qubits, especially the four-qubit GHZ state as used in GHZ's original proposal.


title: Optical spectrum analyzer with quantum limited noise floor

abstract:
  Interactions between atoms and lasers provide the potential for unprecedented
control of quantum states. Fulfilling this potential requires detailed
knowledge of frequency noise in optical oscillators with state-of-the-art
stability. We demonstrate a technique that precisely measures the noise
spectrum of an ultrastable laser using optical lattice-trapped $^{87}$Sr atoms
as a quantum projection noise-limited reference. We determine the laser noise
spectrum from near DC to 100 Hz via the measured fluctuations in atomic
excitation, guided by a simple and robust theory model. The noise spectrum
yields a 26(4) mHz linewidth at a central frequency of 429 THz, corresponding
to an optical quality factor of $1.6\times10^{16}$. This approach improves upon
optical heterodyne beats between two similar laser systems by providing
information unique to a single laser, and complements the traditionally used
Allan deviation which evaluates laser performance at relatively long time
scales. We use this technique to verify the reduction of resonant noise in our
ultrastable laser via feedback from an optical heterodyne beat. Finally, we
show that knowledge of our laser's spectrum allows us to accurately predict the
laser-limited stability for optical atomic clocks.


title:
Work fluctuations in a time-dependent harmonic potential: rigorous
  results and beyond the overdamped limit

abstract:
  We investigate the stochastic motion of a Brownian particle in the harmonic
potential with a time-dependent force constant. It may describe the motion of a
colloidal particle in an optical trap where the potential well is formed by a
time-dependent field. We use the path integral formalism to solve the Langevin
equation and the associated Fokker-Planck (Kramers) equation. Rigorous
relations are derived to generate the probability density function for the
time-dependent nonequilibrium work production beyond the overdamped limit. We
find that the work distribution exhibits an exponential tail with a power-law
prefactor, accompanied by an interesting oscillatory feature (multiple pseudo
locking-unlocking transitions) due to the inertial effect. Some exactly
solvable cases are also discussed in the overdamped limit.


title:
Solubility of Iron in Metallic Hydrogen and Stability of Dense Cores in
  Giant Planets

abstract:
  The formation of the giant planets in our solar system, and likely a majority
of giant exoplanets, is commonly explained by the accretion of nebular hydrogen
and helium onto a large core of terrestrial-like composition. The fate of this
core has important consequences for the evolution of the interior structure of
the planet. It has recently been shown that H2O, MgO and SiO2 dissolve in
liquid metallic hydrogen at high temperature and pressure. In this study, we
perform ab initio calculations to study the solubility of an innermost metallic
core. We find dissolution of iron to be strongly favored above 2000 K over the
entire pressure range (0.4-4 TPa) considered. We compare with and summarize the
results for solubilities on other probable core constituents. The calculations
imply that giant planet cores are in thermodynamic disequilibrium with
surrounding layers, promoting erosion and redistribution of heavy elements.
Differences in solubility behavior between iron and rock may influence
evolution of interiors, particularly for Saturn-mass planets. Understanding the
distribution of iron and other heavy elements in gas giants may be relevant in
understanding mass-radius relationships, as well as deviations in transport
properties from pure hydrogen-helium mixtures.


title:
On confidence intervals in regression that utilize uncertain prior
  information about a vector parameter

abstract:
  Consider a linear regression model with n-dimensional response vector,
p-dimensional regression parameter beta and independent normally distributed
errors. Suppose that the parameter of interest is theta = a^T beta where a is a
specified vector. Define the s-dimensional parameter vector tau=C^T beta-t
where C and t are specified. Also suppose that we have uncertain prior
information that tau=0. Part of our evaluation of a frequentist confidence
interval for theta is the ratio (expected length of this confidence
interval)/(expected length of standard 1-alpha confidence interval), the scaled
expected length of this interval. We say that a 1-alpha confidence interval for
theta utilizes this uncertain prior information if (a) the scaled expected
length of this interval is significantly less than 1 when tau=0, (b) the
maximum value of the scaled expected length is not too large and (c) this
confidence interval reverts to the standard 1-alpha confidence interval when
the data happen to strongly contradict the prior information. Let
hat{Theta}=a^T hat{beta} and hat{tau}=C^T hat{beta}-t, where hat{beta} is the
least squares estimator of beta. We consider the particular case that that
E((hat{tau}-tau)(hat{Theta}-theta))=0, so that hat{Theta} and hat{tau} are
independent. We present a new 1-alpha confidence interval for theta that
utilizes the uncertain prior informationthat tau=0. The following problem is
used to illustrate the application of this new confidence interval. Consider a
2^3 factorial experiment with 1 replicate. Suppose that the parameter of
interest theta is a specified linear combination of the main effects. Assume
that the three-factorinteraction is zero. Also suppose that we have uncertain
prior information that all of the two-factor interactions are zero. Our aim is
to find a frequentist 0.95 confidence interval for theta that utilizes this
uncertain prior information.


title:
Triggering star formation by both radiative and mechanical active
  galactic nucleus feedback

abstract:
  We perform two dimensional hydrodynamic numerical simulations to study the
positive active galactic nucleus feedback which triggers, rather than
suppresses, star formation. Recently, it was shown by Nayakshin et al. and
Ishibashi et al. that star formation occurs when the cold interstellar medium
is squeezed by the impact of mass outflow or radiation pressure, respectively.
Mass outflow is ubiquitous in this astrophysical context, and radiation
pressure is also important if the AGN is luminous. For the first time in this
subject, we incorporate both mass outflow feedback and radiative feedback into
our model. Consequently, the ISM is shocked into shells by the AGN feedback,
and these shells soon fragment into clumps and filaments because of
Rayleigh-Taylor and thermal instabilities. We have two major findings: (1) the
star formation rate can indeed be very large in the clumps and filaments.
However, the resultant star formation rate density is too large compared with
previous works, which is mainly because we ignore the fact that most of the
stars that are formed would be disrupted when they move away from the galactic
center. (2) Although radiation pressure feedback has a limited effect, when
mass outflow feedback is also included, they reinforce each other.
Specifically, in the gas-poor case, mass outflow is always the dominant
contributor to feedback.


title:
Exploiting correlation and budget constraints in Bayesian multi-armed
  bandit optimization

abstract:
  We address the problem of finding the maximizer of a nonlinear smooth
function, that can only be evaluated point-wise, subject to constraints on the
number of permitted function evaluations. This problem is also known as
fixed-budget best arm identification in the multi-armed bandit literature. We
introduce a Bayesian approach for this problem and show that it empirically
outperforms both the existing frequentist counterpart and other Bayesian
optimization methods. The Bayesian approach places emphasis on detailed
modelling, including the modelling of correlations among the arms. As a result,
it can perform well in situations where the number of arms is much larger than
the number of allowed function evaluation, whereas the frequentist counterpart
is inapplicable. This feature enables us to develop and deploy practical
applications, such as automatic machine learning toolboxes. The paper presents
comprehensive comparisons of the proposed approach, Thompson sampling,
classical Bayesian optimization techniques, more recent Bayesian bandit
approaches, and state-of-the-art best arm identification methods. This is the
first comparison of many of these methods in the literature and allows us to
examine the relative merits of their different features.


title: Eliminating cracking during drying

abstract:
  When colloidal suspensions dry, stresses build up and cracks often occur - a
phenomenon undesirable for important industries such as paint and ceramics. We
demonstrate an effective method which can completely eliminate cracking during
drying: by adding emulsion droplets into colloidal suspensions, we can
systematically decrease the amount of cracking, and eliminate it completely
above a critical droplet concentration. Since the emulsion droplets eventually
also evaporate, our technique achieves an effective function while making
little changes to the component of final product, and may therefore serve as a
promising approach for cracking elimination. Furthermore, adding droplets also
varies the speed of air invasion and provides a powerful method to adjust
drying rate. With the effective control over cracking and drying rate, our
study may find important applications in many drying and cracking related
industrial processes.


title:
On the Boundedness of Positive Solutions of the Reciprocal Max-Type
  Difference Equation $x_{n}=\max\left\{\frac{A^{1}_{n-1}}{x_{n-1}},
  \frac{A^{2}_{n-1}}{x_{n-2}}, \ldots, \frac{A^{t}_{n-1}}{x_{n-t}}\right\}$
  with Periodic Parameters

abstract:
  We investigate the boundedness of positive solutions of the reciprocal
max-type difference equation
  \[ x_{n}=\max\left\{\frac{A_{n-1}^{1}}{x_{n-1}}, \frac{A_{n-1}^{2}}{x_{n-2}},
  \ldots, \frac{A_{n-1}^{t}}{x_{n-t}}\right\}, \ \ n=1, 2, \ldots, \]
  where, for each value of $i$, the sequence $\{A_{n}^{i}\}_{n=0}^{\infty}$ of
positive numbers is periodic with period $p_{i}$. We give both sufficient
conditions on the $p_{i}$'s for the boundedness of all solutions and sufficient
conditions for all solutions to be unbounded. This work essentially complements
the work by Biddell and Franke, who showed that as long as every positive
solution of our equation is \emph{bounded}, then every positive solution is
eventually periodic, thereby leaving open the question as to when solutions are
bounded.


title: Impact of accretion on the statistics of neutron star masses

abstract:
  We have collected the parameter of 38 neutron stars (NSs) in binary systems
with spin periods and measured masses. By adopting the Boot-strap method, we
reproduced the procedure of mass calculated for each system separately, to
determine the truly mass distribution of the NS that obtained from observation.
We also applied the Monte-Carlo simulation and introduce the characteristic
spin period 20 ms, in order to distinguish between millisecond pulsars (MSPs)
and less recycled pulsars. The mass distributions of MSPs and the less recycled
pulsars could be fitted by a Gaussian function as $\rm 1.45\pm0.42 M_{\odot}$
and $\rm 1.31\pm0.17 M_{\odot} (\rm with ~ 1\sigma)$ respectively. As such, the
MSP masses are heavier than those in less recycled systems by factor of $\rm
\sim 0.13M_{\odot}$, since the accretion effect during the recycling process.


title:
Sequential testing over multiple stages and performance analysis of data
  fusion

abstract:
  We describe a methodology for modeling the performance of decision-level data
fusion between different sensor configurations, implemented as part of the
JIEDDO Analytic Decision Engine (JADE). We first discuss a Bayesian network
formulation of classical probabilistic data fusion, which allows elementary
fusion structures to be stacked and analyzed efficiently. We then present an
extension of the Wald sequential test for combining the outputs of the Bayesian
network over time. We discuss an algorithm to compute its performance
statistics and illustrate the approach on some examples. This variant of the
sequential test involves multiple, distinct stages, where the evidence
accumulated from each stage is carried over into the next one, and is motivated
by a need to keep certain sensors in the network inactive unless triggered by
other sensors.


title:
A counterexample to weighted estimates for multilinear Fourier
  multipliers with Sobolev regularity

abstract:
  The problem whether weighted estimates for multilinear Fourier multipliers
with Sobolev regularity hold under weak condition on weights is considered.


title: Seifert conjecture in the even convex case

abstract:
  In this paper, we prove that there exist at least $n$ geometrically distinct
brake orbits on every $C^2$ compact convex symmetric hypersurface $\Sg$ in
$\R^{2n}$ satisfying the reversible condition $N\Sg=\Sg$ with $N=\diag
(-I_n,I_n)$. As a consequence, we show that if the Hamiltonian function is
convex and even, then Seifert conjecture of 1948 on the multiplicity of brake
orbits holds for any positive integer $n$.


title: A Federated CloudNet Architecture: The PIP and the VNP Role

abstract:
  We present a generic and flexible architecture to realize CloudNets: virtual
networks connecting cloud resources with resource guarantees. Our architecture
is federated and supports different (and maybe even competing) economical
roles, by providing explicit negotiation and provisioning interfaces.
Contract-based interactions and a resource description language that allows for
aggregation and abstraction, preserve the different roles' autonomy without
sacrificing flexibility. Moreover, since our CloudNet architecture is plugin
based, essentially all cloud operating systems (e.g., OpenStack) or link
technologies (e.g., VLANs, OpenFlow, VPLS) can be used within the framework.
  This paper describes two roles in more detail: The Physical Infrastructure
Providers (PIP) which own the substrate network and resources, and the Virtual
Network Providers (VNP) which can act as resource and CloudNet brokers and
resellers. Both roles are fully implemented in our wide-area prototype that
spans remote sites and resources.


title:
Influence of Quantum and Thermal Noise on Spin-Torque-Driven
  Magnetization Switching

abstract:
  We apply a recently developed quantum theory of spin transfer torque to study
the effect of the quantum noise in spin transfer process on the magnetization
switching in spin-torque-driven devices. The quantum noise induces considerable
fluctuation of the switching time at zero temperature. By including the thermal
noise, the temperature dependence of the expectation value and standard
deviation of the switching time are obtained in the Monte Carlo simulations,
and the results are fitted to an effective first passage model. We expect that
the predictions here are observable in the single-shot measurement experiments.


title: Locally normal subgroups of simple locally compact groups

abstract:
  We announce various results concerning the structure of compactly generated
simple locally compact groups. We introduce a local invariant, called the
structure lattice, which consists of commensurability classes of compact
subgroups with open normaliser, and show that its properties reflect the global
structure of the ambient group.


title: Time Dependence of Particle Creation from Accelerating Mirrors

abstract:
  Particle production due to a quantized, massless, minimally coupled scalar
field in two-dimensional flat spacetime with an accelerating mirror is
investigated, with a focus on the time dependence of the process. We analyze
first the classes of trajectories previously investigated by Carlitz and Willey
and by Walker and Davies. We then analyze four new classes of trajectories, all
of which can be expressed analytically and for which several ancillary
properties can be derived analytically. The time dependence is investigated
through the use of wave packets for the modes of the quantized field that are
in the out vacuum state. It is shown for most of the trajectories studied that
good time resolution of the particle production process can be obtained.


title: Universal prohibited zones in the coordinate space of few-body systems

abstract:
  In some special zones of the high-dimensional coordinate space of few-body
systems with identical particles, the operation of an element (or a product of
elements) of the symmetry groups of the Hamiltonian on a quantum state might be
equivalent to the operation of another element. Making use of the matrix
representations of the groups, the equivalence leads to a set of homogeneous
linear equations imposing on the wave functions. When the matrix of these
equations is non-degenerate, the wave functions will appear as nodal surfaces
in these zones. In this case, these zones are prohibited. In this paper,
tightly bound 4-boson systems with three types of interaction have been studied
analytically and numerically. The existence of the universal prohibited zones
has been revealed, and their decisive effect on the structures of the
eigenstates is demonstrated.


title: Observing Molecular Spinning via the Rotational Doppler Effect

abstract:
  When circularly polarized light is scattered from a rotating target, a
rotational Doppler shift (RDS) emerges from an exchange of angular momentum
between the spinning object and the electromagnetic field. Here, we used
coherently spinning molecules to generate a shift of the frequency of a
circularly polarized probe propagating through a gaseous sample. We used a
linearly polarized laser pulse to align the molecules, followed by a second
delayed pulse polarized at 45{\deg} to achieve unidirectional molecular
rotation. The measured RDS is orders of magnitude greater than previously
observed by other methods. This experiment provides explicit evidence of
unidirectional molecular rotation and paves the way for a new class of
measurements in which the rotational direction of molecular reagents may be
monitored or actively controlled.


title: Chains of Theories and Companionability

abstract:
  The theory of fields that are equipped with a countably infinite family of
commuting derivations is not companionable; but if the axiom is added whereby
the characteristic of the fields is zero, then the resulting theory is
companionable. Each of these two theories is the union of a chain of
companionable theories. In the case of characteristic zero, the
model-companions of the theories in the chain form another chain, whose union
is therefore the model-companion of the union of the original chain. However,
in a signature with predicates, in all finite numbers of arguments, for linear
dependence of vectors, the two-sorted theory of vector-spaces with their
scalar-fields is companionable, and it is the union of a chain of companionable
theories, but the model-companions of the theories in the chain are mutually
inconsistent. Finally, the union of a chain of non-companionable theories may
be companionable.


title: Landau's theorem for polyharmonic mappings

abstract:
  In this paper, we first investigate coefficient estimates for bounded
polyharmonic mappings in the unit disk $\mathbb{D}$. Then, we obtain two
versions of Landau's theorem for polyharmonics mapping $F$, and for the
mappings of the type $L(F)$, where $L$ is the differential operator of
Abdulhadi, Abu Muhanna and Khuri. Examples and numerical estimates are given.


title: Improved Lower Bounds for Sum Coloring via Clique Decomposition

abstract:
  Given an undirected graph $G = (V,E)$ with a set $V$ of vertices and a set
$E$ of edges, the minimum sum coloring problem (MSCP) is to find a legal vertex
coloring of $G$, using colors represented by natural numbers $1, 2, . . .$ such
that the total sum of the colors assigned to the vertices is minimized. This
paper describes an approach based on the decomposition of the original graph
into disjoint cliques for computing lower bounds for the MSCP. Basically, the
proposed approach identifies and removes at each extraction iteration a maximum
number of cliques of the same size (the largest possible) from the graph.
Computational experiments show that this approach is able to improve on the
current best lower bounds for 14 benchmark instances, and to prove optimality
for the first time for 4 instances. We also report lower bounds for 24 more
instances for which no such bounds are available in the literature. These new
lower bounds are useful to estimate the quality of the upper bounds obtained
with various heuristic approaches.


title: The radio-frequency quadrupole

abstract:
  Radio-frequency quadrupole (RFQ) linear accelerators appeared on the
accelerator scene in the late 1970s and have since revolutionized the domain of
low-energy proton and ion acceleration. The RFQ makes the reliable production
of unprecedented ion beam intensities possible within a compact radio-frequency
(RF) resonator which concentrates the three main functions of the low-energy
linac section: focusing, bunching and accelerating. Its sophisticated electrode
structure and strict beam dynamics and RF requirements, however, impose severe
constraints on the mechanical and RF layout, making the construction of RFQs
particularly challenging. This lecture will introduce the main beam optics, RF
and mechanical features of a RFQ emphasizing how these three aspects are
interrelated and how they contribute to the final performance of the RFQ.


title: Optical-radio positional offsets for active galactic nuclei

abstract:
  Context. It will soon become possible to directly link the most accurate
radio reference frame with the Gaia optical reference frame using many common
extragalactic objects. It is important to know the level of coincidence between
the radio and optical positions of compact active galactic nuclei (AGN). Aims.
Using the best catalogues available at present, we investigate how many AGN
with significantly large optical-radio positional offsets exist as well as the
possible causes of these offsets. Methods. We performed a case study by finding
optical counterparts to the International Celestial Reference Frame (ICRF2)
radio sources in the Sloan Digital Sky Survey (SDSS) Data Release 9 (DR9). The
ICRF2 catalogue was used as a reference because the radio positions determined
by Very Long Baseline Interferometry (VLBI) observations are about two orders
of magnitude more accurate than the optical positions. Results. We find 1297
objects in common for ICRF2 and SDSS DR9. Statistical analysis of the
optical-radio differences verifies that the SDSS DR9 positions are accurate to
~55 mas in both coordinates, with no systematic offset with respect to ICRF2.
We find 51 sources (~4% of the sample) for which the positional offset exceeds
170 mas (~3{\sigma}). Astrophysical explanations must exist for most of these
outliers. There are 3 known strong gravitational lenses among them. Dual AGN or
recoiling supermassive black holes may also be possible. Conclusions. The most
accurate Gaia-VLBI reference frame link will require a careful selection of a
common set of objects by eliminating the outliers. On the other hand, the
significant optical-radio positional non-coincidences may offer a new tool for
finding e.g. gravitational lenses or dual AGN candidates. Detailed follow-up
radio interferometric and optical spectroscopic observations are encouraged to
investigate the outlier sources found in this study.


title:
Mobility-enhanced signal response in metapopulation networks of coupled
  oscillators

abstract:
  We investigate the effect of mobility on the response of coupled oscillators
to a subthreshold external signal in metapopulation networks, wherein each node
represents a subpopulation with overdamped bistable oscillators that can
randomly diffuse between nodes. With increasing mobility rate, the oscillators
undergo transitions from intrawell to interwell motion, demonstrating clearly
mobility-enhanced signal amplification. Moreover, the response shows
nonmonotonic dependence on the mobility rate, i.e., a maximal gain occurs at a
moderate level of mobility. This interesting phenomenon is robust against
variations in the overall density, network size, as well as network topology.
In addition, a simple mean-field analysis is carried out to qualitatively
illustrate the simulation results.


title:
Zero Intelligence Models of the Continuous Double Auction: Econometrics,
  Empirical Evidence and Generalization

abstract:
  In the paper, a statistical procedure for estimating the parameters of zero
intelligence models by means of tick-by-tick quote (L1) data is proposed. A
large class of existing zero intelligence models is reviewed. It is shown that
all those models fail to describe the actual behavior of limit order books
close to the ask price. A generalized model, accommodating the discrepancies
found, is proposed and shown to give significant results for L1 data from three
US electronic markets. It is also demonstrated that the generalized model
preforms significantly better than the reviewed models.


title: Linear accelerators

abstract:
  Radio-frequency linear accelerators are used as injectors for synchrotrons
and as stand-alone accelerators for the production of intense particle beams,
thanks to their ability to accelerate high beam currents at high repetition
rates. This lecture introduces their main features, reviewing the different
types of accelerating structures used in linacs and presenting the main
characteristics of linac beam dynamics. Building on these bases, the
architecture of modern proton linear accelerators is presented with a
particular emphasis on high-energy and high-beam-power applications.


title: Specific instrumentation and diagnostics for high-intensity hadron beams

abstract:
  An overview of various typical instruments used for high-intensity hadron
beams is given. In addition, a few important diagnostic methods are discussed
which are quite special for these kinds of beams.


title:
Isotopically modified Ge detectors for {\sc Gerda}: from production to
  operation

abstract:
  The \textsc{Gerda} experiment searches for the neutrinoless double beta
($0\nu\beta$beta$) decay of $^{76}$Ge using high-purity germanium detectors
made of material enriched in $^{76}$Ge. For Phase II of the experiment a
sensitivity for the half life $T_{1/2}^{0\nu}\,\,\sim2\cdot10^{26}$ yr is
envisioned. Modified Broad Energy Germanium detectors (BEGe) with thick n$^+$
electrodes provide the capability to efficiently identify and reject background
events, while keeping a large acceptance for the $0\nu\beta$beta$-decay signal
through novel pulse-shape discrimination (PSD) techniques.
  The viability of producing thick-window BEGe-type detectors for the
\textsc{Gerda} experiment is demonstrated by testing all the production steps
from the procurement of isotopically modified germanium up to working BEGe
detectors. Comprehensive testing of the spectroscopic as well as PSD
performance of the \textsc{Gerda} Phase II prototype BEGe detectors proved that
the properties of these detectors are identical to those produced previously
from natural germanium material following the standard production line of the
manufacturer.
  Furthermore, the production of BEGe detectors from a limited amount of
isotopically modified germanium served to optimize the production, in order to
maximize the overall detector mass yield. The results of this test campaign
provided direct input for the subsequent production of the enriched germanium
detectors.


title: Maximal Blaschke Products

abstract:
  We consider the classical problem of maximizing the derivative at a fixed
point over the set of all bounded analytic functions in the unit disk with
prescribed critical points. We show that the extremal function is essentially
unique and always an indestructible Blaschke product. This result extends the
Nehari--Schwarz Lemma and leads to a new class of Blaschke products called
maximal Blaschke products. We establish a number of properties of maximal
Blaschke products, which indicate that maximal Blaschke products constitute an
appropriate infinite generalization of the class of finite Blaschke products.


title:
A second note on the discrete Gaussian Free Field with disordered
  pinning on Z^d, d\geq 2

abstract:
  We study the discrete massless Gaussian Free Field on Z^d, d \geq 2, in the
presence of a disordered square-well potential supported on a finite strip
around zero. The disorder is introduced by reward/penalty interaction
coefficients, which are given by i.i.d. random variables. In the previous note,
we proved under minimal assumptions on the law of the environment, that the
quenched free energy associated to this model exists in R^+, is deterministic,
and strictly smaller than the annealed free energy whenever the latter is
strictly positive. Here we consider Bernoulli reward/penalty coefficients b e_x
+ h with P(e_x=-1)=P(e_x=+1)=1/2 for all x in Z^d, and b > 0, h in R. We prove
that in the plane (b,h), the quenched critical line (separating the phases of
positive and zero free energy) lies strictly below the line h = 0, showing in
particular that there exists a non trivial region where the field is localized
though repulsed on average by the environment.

categories: math.PR cond-mat.stat-mech math-ph math.MP


title:
Optimal Power Allocation over Multiple Identical Gilbert-Elliott
  Channels

abstract:
  We study the fundamental problem of power allocation over multiple
Gilbert-Elliott communication channels. In a communication system with time
varying channel qualities, it is important to allocate the limited transmission
power to channels that will be in good state. However, it is very challenging
to do so because channel states are usually unknown when the power allocation
decision is made. In this paper, we derive an optimal power allocation policy
that can maximize the expected discounted number of bits transmitted over an
infinite time span by allocating the transmission power only to those channels
that are believed to be good in the coming time slot. We use the concept belief
to represent the probability that a channel will be good and derive an optimal
power allocation policy that establishes a mapping from the channel belief to
an allocation decision.
  Specifically, we first model this problem as a partially observable Markov
decision processes (POMDP), and analytically investigate the structure of the
optimal policy. Then a simple threshold-based policy is derived for a
three-channel communication system. By formulating and solving a linear
programming formulation of this power allocation problem, we further verified
the derived structure of the optimal policy.


title:
Renormalization of an SU(2) Tensorial Group Field Theory in Three
  Dimensions

abstract:
  We address in this paper the issue of renormalizability for SU(2) Tensorial
Group Field Theories (TGFT) with geometric Boulatov-type conditions in three
dimensions. We prove that tensorial interactions up to degree 6 are just
renormalizable without any anomaly. Our new models define the renormalizable
TGFT version of the Boulatov model and provide therefore a new approach to
quantum gravity in three dimensions. Among the many new technical results
established in this paper are a general classification of just renormalizable
models with gauge invariance condition, and in particular concerning properties
of melonic graphs, the second order expansion of melonic two point subgraphs
needed for wave-function renormalization.


title: Accuracy of magnetic energy computations

abstract:
  For magnetically driven events, the magnetic energy of the system is the
prime energy reservoir that fuels the dynamical evolution. In the solar
context, the free energy is one of the main indicators used in space weather
forecasts to predict the eruptivity of active regions. A trustworthy estimation
of the magnetic energy is therefore needed in three-dimensional models of the
solar atmosphere, eg in coronal fields reconstructions or numerical
simulations. The expression of the energy of a system as the sum of its
potential energy and its free energy (Thomson's theorem) is strictly valid when
the magnetic field is exactly solenoidal. For numerical realizations on a
discrete grid, this property may be only approximately fulfilled. We show that
the imperfect solenoidality induces terms in the energy that can lead to
misinterpreting the amount of free energy present in a magnetic configuration.
We consider a decomposition of the energy in solenoidal and nonsolenoidal parts
which allows the unambiguous estimation of the nonsolenoidal contribution to
the energy. We apply this decomposition to six typical cases broadly used in
solar physics. We quantify to what extent the Thomson theorem is not satisfied
when approximately solenoidal fields are used. The quantified errors on energy
vary from negligible to significant errors, depending on the extent of the
nonsolenoidal component. We identify the main source of errors and analyze the
implications of adding a variable amount of divergence to various solenoidal
fields. Finally, we present pathological unphysical situations where the
estimated free energy would appear to be negative, as found in some previous
works, and we identify the source of this error to be the presence of a finite
divergence. We provide a method of quantifying the effect of a finite
divergence in numerical fields, together with detailed diagnostics of its
sources.


title: Hyperbolic groups with homeomorphic Gromov boundaries

abstract:
  We show that the Gromov boundary of the free product of two infinite
hyperbolic groups is uniquely determined up to homeomorphism by the
homeomorphism types of the boundaries of its factors. We generalize this result
to graphs of hyperbolic groups over finite subgroups. Finally, we give a
necessary and sufficient condition for the Gromov boundaries of any two
hyperbolic groups to be homeomorphic (in terms of the topology of the
boundaries of factors in terminal splittings over finite subgroups).


title:
Dynamic Provisioning in Next-Generation Data Centers with On-site Power
  Production

abstract:
  The critical need for clean and economical sources of energy is transforming
data centers that are primarily energy consumers to also energy producers. We
focus on minimizing the operating costs of next-generation data centers that
can jointly optimize the energy supply from on-site generators and the power
grid, and the energy demand from servers as well as power conditioning and
cooling systems. We formulate the cost minimization problem and present an
offline optimal algorithm. For "on-grid" data centers that use only the grid,
we devise a deterministic online algorithm that achieves the best possible
competitive ratio of $2-\alpha_{s}$, where $\alpha_{s}$ is a normalized
look-ahead window size. For "hybrid" data centers that have on-site power
generation in addition to the grid, we develop an online algorithm that
achieves a competitive ratio of at most \textmd{\normalsize {\small
$\frac{P_{\max} (2-\alpha_{s})}{c_{o}+c_{m}/L}
[1+2\frac{P_{\max}-c_{o}}{P_{\max}(1+\alpha_{g})}]$}}, where $\alpha_{s}$ and
$\alpha_{g}$ are normalized look-ahead window sizes, $P_{\max}$ is the maximum
grid power price, and $L$, $c_{o}$, and $c_{m}$ are parameters of an on-site
generator.
  Using extensive workload traces from Akamai with the corresponding grid power
prices, we simulate our offline and online algorithms in a realistic setting.
Our offline (resp., online) algorithm achieves a cost reduction of 25.8%
(resp., 20.7%) for a hybrid data center and 12.3% (resp., 7.3%) for an on-grid
data center. The cost reductions are quite significant and make a strong case
for a joint optimization of energy supply and energy demand in a data center. A
hybrid data center provides about 13% additional cost reduction over an on-grid
data center representing the additional cost benefits that on-site power
generation provides over using the grid alone.


title: Perturbatively improving RI-MOM renormalization constants

abstract:
  The determination of renormalization factors is of crucial importance in
lattice QCD. They relate the observables obtained on the lattice to their
measured counterparts in the continuum in a suitable renormalization scheme.
Therefore, they have to be computed as precisely as possible. A widely used
approach is the nonperturbative Rome-Southampton method. It requires, however,
a careful treatment of lattice artifacts. In this paper we investigate a method
to suppress these artifacts by subtracting one-loop contributions to
renormalization factors calculated in lattice perturbation theory. We compare
results obtained from a complete one-loop subtraction with those calculated for
a subtraction of contributions proportional to the square of the lattice
spacing.


title: A Graphical Language for Real-Time Critical Robot Commands

abstract:
  Industrial robotics is characterized by sophisticated mechanical components
and highly-developed real-time control algorithms. However, the efficient use
of robotic systems is very much limited by existing proprietary programming
methods. In the research project SoftRobot, a software architecture was
developed that enables the programming of complex real-time critical robot
tasks with an object-oriented general purpose language. On top of this
architecture, a graphical language was developed to ease the specification of
complex robot commands, which can then be used as part of robot application
workflows. This paper gives an overview about the design and implementation of
this graphical language and illustrates its usefulness with some examples.


title:
A Constrained-Path Quantum Monte-Carlo Approach for the Nuclear Shell
  Model

abstract:
  A new Quantum Monte-Carlo (QMC) approach is proposed to investigate low-lying
states of nuclei within the shell model. The formalism relies on a variational
symmetry-restored wave-function to guide the underlying Brownian motion.
Sign/phase problems that usually plague QMC fermionic simulations are
controlled by constraining stochastic paths through a fixed-node like
approximation. Exploratory results in the sd and pf valence spaces with
realistic effective interactions are presented. They prove the ability of the
scheme to yield nearly exact yrast spectroscopies for both even- and odd-mass
nuclei.


title:
Elasto-capillarity at the nanoscale: on the coupling between elasticity
  and surface energy in soft solids

abstract:
  The capillary forces exerted by liquid drops and bubbles on a soft solid are
directly measured using molecular dynamics simulations. The force on the solid
by the liquid near the contact line is not oriented along the liquid vapor
interface nor perpendicular to the solid surface, as usually assumed, but
points towards the liquid.
  It is shown that the elastic deformations induced by this force can only be
explained if, contrary to an incompressible liquid, the surface stress is
different from the surface energy. Using thermodynamic variations we show that
the the surface stress and the surface energy can both be determined accurately
by measuring the deformation of a slender body plunged in a liquid. The results
obtained from molecular dynamics fully confirm those recently obtained
experimentally [Marchand et al. Phys. Rev. Lett. 108, 094301 (2012)] for an
elastomeric wire.


title: Semigroups of Herz-Schur Multipliers

abstract:
  In order to investigate the relationship between weak amenability and the
Haagerup property for groups, we introduce the weak Haagerup property, and we
prove that having this approximation property is equivalent to the existence of
a semigroup of Herz-Schur multipliers generated by a proper function. It is
then shown that a (not necessarily proper) generator of a semigroup of
Herz-Schur multipliers splits into a positive definite kernel and a
conditionally negative definite kernel. We also show that the generator has a
particularly pleasant form if and only if the group is amenable.
  In the second half of the paper we study semigroups of radial Herz-Schur
multipliers on free groups. We prove that a generator of such a semigroup is
linearly bounded by the word length function.


title: Superluminal Waves and the Structure of Pulsar Wind Termination Shocks

abstract:
  The termination shock of a pulsar wind is located roughly where the ram
pressure matches that of the surrounding medium. Downstream of the shock, MHD
models of the diffuse nebular emission suggest the plasma is weakly magnetized.
However, the transition from a Poynting-dominated MHD wind to a
particle-dominated flow is not well understood. We discuss a solution of this
"sigma problem" in which a striped wind converts into a strong, superluminal
electromagnetic wave. This mode slows down as it propagates radially, and its
ram pressure tends to a constant value at large radius, a property we use to
match the solution to the surrounding nebula. The wave thus forms a pre-cursor
to the termination shock, which occurs at the point where the wave dissipates.
Possible damping and dissipation mechanisms are discussed qualitatively.


title: Systematic Mapping Study On Security Threats in Cloud Computing

abstract:
  Today, Cloud Computing is rising strongly, presenting itself to the market by
its main service models, known as IaaS, PaaS and SaaS, that offer advantages in
operational investments by means of on-demand costs, where consumers pay by
resources used. In face of this growth, security threats also rise,
compromising the Confidentiality, Integrity and Availability of the services
provided. Our work is a Systematic Mapping where we hope to present metrics
about publications available in literature that deal with some of the seven
security threats in Cloud Computing, based in the guide entitled "Top Threats
to Cloud Computing" from the Cloud Security Alliance (CSA). In our research we
identified the more explored threats, distributed the results between fifteen
Security Domains and identified the types of solutions proposed for the
threats. In face of those results, we highlight the publications that are
concerned to fulfill some standard of compliance.


title: Space based microlensing planet searches

abstract:
  The discovery of extra-solar planets is arguably the most exciting
development in astrophysics during the past 15 years, rivalled only by the
detection of dark energy. Two projects unite the communities of exoplanet
scientists and cosmologists: the proposed ESA M class mission EUCLID and the
large space mission WFIRST, top ranked by the Astronomy 2010 Decadal Survey
report. The later states that: "Space-based microlensing is the optimal
approach to providing a true statistical census of planetary systems in the
Galaxy, over a range of likely semi-major axes". They also add: "This census,
combined with that made by the Kepler mission, will determine how common
Earth-like planets are over a wide range of orbital parameters". We will
present a status report of the results obtained by microlensing on exoplanets
and the new objectives of the next generation of ground based wide field imager
networks. We will finally discuss the fantastic prospect offered by space based
microlensing at the horizon 2020-2025.


title: Measuring the likelihood of models for network evolution

abstract:
  Many researchers have hypothesised models which explain the evolution of the
topology of a target network. The framework described in this paper gives the
likelihood that the target network arose from the hypothesised model. This
allows rival hypothesised models to be compared for their ability to explain
the target network. A null model (of random evolution) is proposed as a
baseline for comparison. The framework also considers models made from linear
combinations of model components. A method is given for the automatic
optimisation of component weights. The framework is tested on simulated
networks with known parameters and also on real data.


title: Latency-Bounded Target Set Selection in Social Networks

abstract:
  Motivated by applications in sociology, economy and medicine, we study
variants of the Target Set Selection problem, first proposed by Kempe,
Kleinberg and Tardos. In our scenario one is given a graph $G=(V,E)$, integer
values $t(v)$ for each vertex $v$ (\emph{thresholds}), and the objective is to
determine a small set of vertices (\emph{target set}) that activates a given
number (or a given subset) of vertices of $G$ \emph{within} a prescribed number
of rounds. The activation process in $G$ proceeds as follows: initially, at
round 0, all vertices in the target set are activated; subsequently at each
round $r\geq 1$ every vertex of $G$ becomes activated if at least $t(v)$ of its
neighbors are already active by round $r-1$. It is known that the problem of
finding a minimum cardinality Target Set that eventually activates the whole
graph $G$ is hard to approximate to a factor better than
$O(2^{\log^{1-\epsilon}|V|})$. In this paper we give \emph{exact} polynomial
time algorithms to find minimum cardinality Target Sets in graphs of bounded
clique-width, and \emph{exact} linear time algorithms for trees.


title: Defect Motifs for Constant Mean Curvature Surfaces

abstract:
  The energy landscapes of electrostatically charged particles embedded on
constant mean curvature surfaces are analysed for a wide range of system size,
curvature, and interaction potentials. The surfaces are taken to be rigid, and
the basin-hopping method is used to locate the putative global minimum
structures. The defect motifs favoured by potential energy agree with
experimental observations for colloidal systems: extended defects (scars and
pleats) for weakly positive and negative Gaussian curvatures, and isolated
defects for strongly negative Gaussian curvatures. Near the phase boundary
between these regimes the two motifs are in strong competition, as evidenced
from the appearance of distinct funnels in the potential energy landscape. We
also report a novel defect motif consisting of pentagon pairs.


title: Measuring the rotation period distribution of field M-dwarfs with Kepler

abstract:
  We have analysed 10 months of public data from the Kepler space mission to
measure rotation periods of main-sequence stars with masses between 0.3 and
0.55 M_sun. To derive the rotational period we introduce the autocorrelation
function and show that it is robust against phase and amplitude modulation and
residual instrumental systematics. Of the 2483 stars examined, we detected
rotation periods in 1570 (63.2%), representing an increase of a factor ~ 30 in
the number of rotation period determination for field M-dwarfs. The periods
range from 0.37-69.7 days, with amplitudes ranging from 1.0-140.8 mmags. The
rotation period distribution is clearly bimodal, with peaks at ~ 19 and ~ 33
days, hinting at two distinct waves of star formation, a hypothesis that is
supported by the fact that slower rotators tend to have larger proper motions.
The two peaks of the rotation period distribution form two distinct sequences
in period-temperature space, with the period decreasing with increasing
temperature, reminiscent of the Vaughan-Preston gap. The period-mass
distribution of our sample shows no evidence of a transition at the fully
convective boundary. On the other hand, the slope of the upper envelope of the
period-mass relation changes sign around 0.55 M_sun, below which period rises
with decreasing mass.


title: High-energy emission from pulsar binaries

abstract:
  Unpulsed, high-energy emission from pulsar binaries can be attributed to the
interaction of a pulsar wind with that of a companion star. At the shock
between the outflows, particles carried away from the pulsar magnetosphere are
accelerated and radiate both in synchrotron and inverse Compton processes. This
emission constitutes a significant fraction of the pulsar spin-down luminosity.
It is not clear however, how the highly magnetized pulsar wind could convert
its mainly electromagnetic energy into the particles with such high efficiency.
Here we investigate a scenario in which a pulsar striped wind converts into a
strong electromagnetic wave before reaching the shock. This mode can be thought
of as a shock precursor that is able to accelerate particles to
ultrarelativistic energies at the expense of the electromagnetic energy it
carries. Radiation of the particles leads to damping of the wave. The
efficiency of this process depends on the physical conditions imposed by the
external medium. Two regimes can be distinguished: a high density one, where
the EM wave cannot be launched at all and the current sheets in the striped
wind are first compressed by an MHD shock and subsequently dissipate by
reconnection, and a low density one, where the wind can first convert into an
electromagnetic wave in the shock precursor, which then damps and merges into
the surroundings. Shocks in binary systems can transit from one regime to
another according to binary phase. We discuss possible observational
implications for these objects.


title: Nonequilibrium electron rings for synchrotron radiation production

abstract:
  Electron storage rings used for the production of synchrotron radiation (SR)
have an output photon brightness that is limited by the equilibrium beam
emittance. By using interleaved injection and ejection of bunches from a source
with repetition rate greater than 1 kHz, we show that it is practicable to
overcome this limit in rings of energy ~1 GeV. Sufficiently short kicker pulse
lengths enable effective currents of many milliamperes, which can deliver a
significant flux of diffraction-limited soft X-ray photons. Thus, either
existing SR facilities may be adapted for non-equilibrium operation, or the
technique applied to construct SR rings smaller than their storage ring
equivalent.


title:
A classification of the irreducible algebraic A-hypergeometric functions
  associated to planar point configurations

abstract:
  We consider A-hypergeometric functions associated to normal sets in the
plane. We give a classification of all point configurations for which there
exists a parameter vector such that the associated hypergeometric function is
algebraic. In particular, we show that there are no irreducible algebraic
functions if the number of boundary points is sufficiently large and A is not a
pyramid.


title: Magnetization relaxation and geometric forces in a Bose ferromagnet

abstract:
  We construct the hydrodynamic theory for spin 1/2 Bose gases at arbitrary
temperatures. This theory describes the coupling between the magnetization, and
the normal and superfluid components of the gas. In particular, our theory
contains the geometric forces on the particles that arise from their spin's
adiabatic following of the magnetization texture. The phenomenological
parameters of the hydrodynamic theory are calculated in the Bogoliubov
approximation and using the Boltzmann equation in the relaxation-time
approximation. We consider the topological Hall effect due to the presence of a
skyrmion, and show that this effect manifests itself in the collective modes of
the system. The dissipative coupling between the magnetization and the normal
component is shown to give rise to magnetization relaxation that is fourth
order in spatial gradients of the magnetization direction.


title: High points for the membrane model in the critical dimension

abstract:
  In this notice we would like to study the fractal structure of the set of
high points for the membrane model in the critical dimension d=4. We are able
to compute the Hausdorff dimension of the set of points which are atypically
high, and also that of clusters, showing that high points tend not to be evenly
spread on the lattice. We will see that these results follow closely those
obtained by Olivier Daviaud for the 2-dimensional discrete Gaussian Free Field.


title: The effects of transcription factor competition on gene regulation

abstract:
  Transcription factor (TF) molecules translocate by facilitated diffusion (a
combination of 3D diffusion around and 1D random walk on the DNA). Despite the
attention this mechanism received in the last 40 years, only a few studies
investigated the influence of the cellular environment on the facilitated
diffusion mechanism and, in particular, the influence of `other' DNA binding
proteins competing with the TF molecules for DNA space. Molecular crowding on
the DNA is likely to influence the association rate of TFs to their target site
and the steady state occupancy of those sites, but it is still not clear how it
influences the search in a genome-wide context, when the model includes
biologically relevant parameters (such as: TF abundance, TF affinity for DNA
and TF dynamics on the DNA). We performed stochastic simulations of TFs
performing the facilitated diffusion mechanism, and considered various
abundances of cognate and non-cognate TFs. We show that, for both obstacles
that move on the DNA and obstacles that are fixed on the DNA, changes in search
time are not statistically significant in case of biologically relevant
crowding levels on the DNA. In the case of non-cognate proteins that slide on
the DNA, molecular crowding on the DNA always leads to statistically
significant lower levels of occupancy, which may confer a general mechanism to
control gene activity levels globally. When the `other' molecules are immobile
on the DNA, we found a completely different behaviour, namely: the occupancy of
the target site is always increased by higher molecular crowding on the DNA.
Finally, we show that crowding on the DNA may increase transcriptional noise
through increased variability of the occupancy time of the target sites.


title:
A likelihood based framework for assessing network evolution models
  tested on real network data

abstract:
  This paper presents a statistically sound method for using likelihood to
assess potential models of network evolution. The method is tested on data from
five real networks. Data from the internet autonomous system network, from two
photo sharing sites and from a co-authorship network are tested using this
framework.


title: Peano phenomenon for stochastic equations with local time

abstract:
  We investigate weak convergence of measures generated by solutions of
stochastic equations with local time and small diffusion while the last one
tends to zero. In case the correspondent ordinary differential equation has
infinitely many solutions we prove that limit measure concentrated with some
weights on its extreme solutions. Formulae for weights are obtained.


title: R-adaptive multisymplectic and variational integrators

abstract:
  Moving mesh methods (also called r-adaptive methods) are space-adaptive
strategies used for the numerical simulation of time-dependent partial
differential equations. These methods keep the total number of mesh points
fixed during the simulation, but redistribute them over time to follow the
areas where a higher mesh point density is required. There are a very limited
number of moving mesh methods designed for solving field-theoretic partial
differential equations, and the numerical analysis of the resulting schemes is
challenging. In this paper we present two ways to construct r-adaptive
variational and multisymplectic integrators for (1+1)-dimensional Lagrangian
field theories. The first method uses a variational discretization of the
physical equations and the mesh equations are then coupled in a way typical of
the existing r-adaptive schemes. The second method treats the mesh points as
pseudo-particles and incorporates their dynamics directly into the variational
principle. A user-specified adaptation strategy is then enforced through
Lagrange multipliers as a constraint on the dynamics of both the physical field
and the mesh points. We discuss the advantages and limitations of our methods.
Numerical results for the Sine-Gordon equation are also presented.


title:
Asymptotic Behaviour of an Infinitely-Many-Alleles Diffusion with
  Symmetric Overdonminance

abstract:
  This paper considers the limiting distribution of $\pi_{\lambda,\theta}$, the
stationary distribution of the infinitely-many-alleles diffusion with symmetric
overdominance \cite{MR1626158}. In \cite{MR2519357} the large deviation
principle for $\pi_{\lambda,\theta}$ indicates that there are countably many
phase transitions for the limiting distribution of $\pi_{\lambda,\theta}$, and
the critical points are $\lambda=k(k+1), k\geq1$. The asymptotic behaviours at
those critical points, however, are unclear. This article provides a definite
description of the critical cases.


title: Electromagnetic form factors of octet baryons in QCD

abstract:
  The electromagnetic form factors of octet baryons are estimated within light
cone QCD sum rules method, using the most general form of the interpolating
current for baryons. A comparison of our predictions on the magnetic dipole and
electric form factors with the results of other approaches is performed.


title: Proving the Pressing Game Conjecture on Linear Graphs

abstract:
  The pressing game on black-and-white graphs is the following: Given a graph
$G(V,E)$ with its vertices colored with black and white, any black vertex $v$
can be pressed, which has the following effect: (a) all neighbors of $v$ change
color, i.e. white neighbors become black and \emph{vice versa}, (b) all pairs
of neighbors of $v$ change connectivity, i.e. connected pairs become
unconnected, unconnected ones become connected, (c) and finally, $v$ becomes a
separated white vertex. The aim of the game is to transform $G$ into an all
white, empty graph. It is a known result that the all white empty graph is
reachable in the pressing game if each component of $G$ contains at least one
black vertex, and for a fixed graph, any successful transformation has the same
number of pressed vertices.
  The pressing game conjecture is that any successful pressing path can be
transformed into any other successful pressing path with small alterations.
Here we prove the conjecture for linear graphs. The connection to genome
rearrangement and sorting signed permutations with reversals is also discussed.


title: Nonequilibrium adsorption of 2AnB patchy colloids on substrates

abstract:
  We study the irreversible adsorption of spherical $2AnB$ patchy colloids
(with two $A$-patches on the poles and $n$ $B$-patches along the equator) on a
substrate. In particular, we consider dissimilar $AA$, $AB$, and $BB$ binding
probabilities. We characterize the patch-colloid network and its dependence on
$n$ and on the binding probabilities. Two growth regimes are identified with
different density profiles and we calculate a growth mode diagram as a function
of the colloid parameters. We also find that, close to the substrate, the
density of the network, which depends on the colloid parameters, is
characterized by a depletion zone.


title: Enumerating Some Fractional Repetition Codes

abstract:
  In a distributed storage systems (DSS), regenerating codes are used to
optimize bandwidth in the repair process of a failed node. To optimize other
DSS parameters such as computation and disk I/O, Distributed Replication-based
Simple Storage (Dress) Codes consisting of an inner Fractional Repetition (FR)
code and an outer MDS code are commonly used. Thus constructing FR codes is an
important research problem, and several constructions using graphs and designs
have been proposed. In this paper, we present an algorithm for constructing the
node-packet distribution matrix of FR codes and thus enumerate some FR codes up
to a given number of nodes n. We also present algorithms for constructing
regular graphs which give rise to FR codes.


title: Symmetry Type Graphs of Abstract Polytopes and Maniplexes

abstract:
  A $k$-orbit maniplex is one that has $k$ orbits of flags under the action of
its automorphism group. In this paper we extend the notion of symmetry type
graphs of maps to that of maniplexes and polytopes and make use of them to
study $k$-orbit maniplexes, as well as fully-transitive 3-maniplexes. In
particular, we show that there are no fully-transtive $k$-orbit 3-mainplexes
with $k > 1$ an odd number, we classify 3-orbit mainplexes and determine all
face transitivities for 3- and 4-orbit maniplexes. Moreover, we give generators
of the automorphism group of a polytope or a maniplex, given its symmetry type
graph. Finally, we extend these notions to oriented polytopes, in particular we
classify oriented 2-orbit maniplexes and give generators for their orientation
preserving automorphism group.


title:
Partial Star Products: A Local Covering Approach for the Recognition of
  Approximate Cartesian Product Graphs

abstract:
  This paper is concerned with the recognition of approximate graph products
with respect to the Cartesian product. Most graphs are prime, although they can
have a rich product-like structure. The proposed algorithms are based on a
local approach that covers a graph by small subgraphs, so-called partial star
products, and then utilizes this information to derive the global factors and
an embedding of the graph under investigation into Cartesian product graphs.


title:
Potential Biosignatures in Super-Earth Atmospheres II. Photochemical
  Responses

abstract:
  Spectral characterization of Super-Earth atmospheres for planets orbiting in
the Habitable Zone of M-dwarf stars is a key focus in exoplanet science. A
central challenge is to understand and predict the expected spectral signals of
atmospheric biosignatures (species associated with life). Our work applies a
global-mean radiative-convective-photochemical column model assuming a planet
with an Earth-like biomass and planetary development. We investigated planets
with gravities of 1g and 3g and a surface pressure of one bar around central
stars with spectral classes from M0 to M7. The spectral signals of the
calculated planetary scenarios have been presented by Rauer et al. (2011). The
main motivation of the present work is to perform a deeper analysis of the
chemical processes in the planetary atmospheres. We apply a diagnostic tool,
the Pathway Analysis Program, to shed light on the photochemical pathways that
form and destroy biosignature species. Ozone is a potential biosignature for
complex- life. An important result of our analysis is a shift in the ozone
photochemistry from mainly Chapman production (which dominates in the
terrestrial stratosphere) to smog-dominated ozone production for planets in the
Habitable Zone of cooler (M5-M7)-class dwarf stars. This result is associated
with a lower energy flux in the UVB wavelength range from the central star,
hence slower planetary atmospheric photolysis of molecular oxygen, which slows
the Chapman ozone production.


title: Kinetic Scheme for Solving M1 Model of Radiative Transfer

abstract:
  We show a numerical scheme to solve the moment equations of the radiative
transfer, i.e., M1 model which follows the evolution of the energy density, $ E
$, and the energy flux, $ \mbox{\boldmath$F$} $. In our scheme we reconstruct
the intensity from $ E $ and $ \mbox{\boldmath$F$} $ so that it is consistent
with the closure relation, relation, $ \chi = (3 + 4 f ^2)/(5 + 2 \sqrt{4 - 3 f
^2}) $.
  Here the symbols, $ \chi $, $ f = |\mbox{\boldmath$F$}|/(cE) $, and $ c $,
denote the Eddington factor, the reduced flux, and the speed of light,
respectively. We evaluate the numerical flux across the cell surface from the
kinetically reconstructed intensity. It is an explicit function of $ E $ and $
\mbox{\boldmath$F$} $ in the neighboring cells across the surface considered.
We include absorption and reemission within a numerical cell in the evaluation
of the numerical flux. The numerical flux approaches to the diffusion
approximation when the numerical cell itself is optically thick. Our numerical
flux gives a stable solution even when some regions computed are very optically
thick. We show the advantages of the numerical flux with examples. They include
flash of beamed photons and irradiated protoplanetary disks.


title:
Green polynomials of Weyl groups, elliptic pairings, and the extended
  Dirac index

abstract:
  We provide a direct connection between Springer theory, via Green
polynomials, the irreducible representations of the pin cover $\wti W$, a
certain double cover of the Weyl group $W$, and an extended Dirac operator for
graded Hecke algebras. Our approach leads to a new and uniform construction of
the irreducible genuine $\wti W$-characters. In the process, we give a
construction of the action by an outer automorphism of the Dynkin diagram on
the cohomology groups of Springer theory, and we also introduce a $q$-elliptic
pairing for $W$ with respect to the reflection representation $V$. These
constructions are of independent interest. The $q$-elliptic pairing is a
generalization of the elliptic pairing of $W$ introduced by Reeder, and it is
also related to S. Kato's notion of (graded) Kostka systems for the semidirect
product $A_W=\bC[W]\ltimes S(V)$.


title:
The performance of locality-aware topologies for peer-to-peer live
  streaming

abstract:
  This paper is concerned with the effect of overlay network topology on the
performance of live streaming peer-to-peer systems. The paper focuses on the
evaluation of topologies which are aware of the delays experienced between
different peers on the network. Metrics are defined which assess the topologies
in terms of delay, bandwidth usage and resilience to peer drop-out. Several
topology creation algorithms are tested and the metrics are measured in a
simple simulation testbed. This gives an assessment of the type of gains which
might be expected from locality awareness in peer-to-peer networks.


title:
LOPES-3D, an antenna array for full signal detection of air-shower radio
  emission

abstract:
  To better understand the radio signal emitted by extensive air-showers and to
further develop the radio detection technique of high-energy cosmic rays, the
LOPES experiment was reconfigured to LOPES-3D. LOPES-3D is able to measure all
three vectorial components of the electric field of radio emission from cosmic
ray air showers. The additional measurement of the vertical component ought to
increase the reconstruction accuracy of primary cosmic ray parameters like
direction and energy, provides an improved sensitivity to inclined showers, and
will help to validate simulation of the emission mechanisms in the atmosphere.
LOPES-3D will evaluate the feasibility of vectorial measurements for large
scale applications. In order to measure all three electric field components
directly, a tailor-made antenna type (tripoles) was deployed. The change of the
antenna type necessitated new pre-amplifiers and an overall recalibration. The
reconfiguration and the recalibration procedure are presented and the
operationality of LOPES-3D is demonstrated.


title:
Thermodynamics of a continuous medium with electric dipoles and magnetic
  moments

abstract:
  The thermodynamics of an electrically charged, multicomponent fluid with
spontaneous electric dipoles and magnetic moments is analysed in the presence
of electromagnetic fields. Taking into account the chemical composition of the
current densities and stress tensors leads to three types of dissipation terms:
scalars, vectors and pseudo-vectors. The scalar terms account for chemical
reactivities, the vectorial terms account for transport and the
pseudo-vectorial terms account for relaxation. The linear phenomenological
relations, derived from the irreversible evolution, describe notably the
Lehmann and electric Lehmann effects, the Debye relaxation of polar molecules
and the Landau-Lifshitz relaxation of the magnetisation. This formalism
accounts for the thermal and electric magnetisation accumulations and
magnetisation waves. It also predicts that a temperature gradient affects the
dynamics of magnetic vortices and drives magnetisation waves.


title: Spin noise spectroscopy: From proof of the principle to applications

abstract:
  More than 30 years ago, the feasibility of detecting magnetic resonance in
the Faraday-rotation noise spectrum of transmitted light has been demonstrated
experimentally. However, practical applications of this experimental approach
have emerged only recently thanks, in particular, to a number of crucial
technical ements. This method has now become a popular and efficient tool for
studying magnetic resonance and spin dynamics in atomic and solid-state
paramagnets. In this paper, we present a review of research in the field of
spin noise spectroscopy including its physical basis, its evolution since its
first experimental demonstration, and its recent experimental advances. Main
attention is paid to the specific capabilities of this technique that render it
unique compared to other methods of magnetic and optical spectroscopy. The
paper is primarily intended for the experimentalists who may wish to use this
novel optical technique.


title: Sparse approximation and recovery by greedy algorithms in Banach spaces

abstract:
  We study sparse approximation by greedy algorithms. We prove the
Lebesgue-type inequalities for the Weak Chebyshev Greedy Algorithm (WCGA), a
generalization of the Weak Orthogonal Matching Pursuit to the case of a Banach
space. The main novelty of these results is a Banach space setting instead of a
Hilbert space setting. The results are proved for redundant dictionaries
satisfying certain conditions. Then we apply these general results to the case
of bases. In particular, we prove that the WCGA provides almost optimal sparse
approximation for the trigonometric system in $L_p$, $2\le p<\infty$.


title:
mu Eridani from MOST and from the ground: an orbit, the SPB component's
  fundamental parameters, and the SPB frequencies

abstract:
  MOST time-series photometry of mu Eri, an SB1 eclipsing binary with a
rapidly-rotating SPB primary, is reported and analyzed. The analysis yields a
number of sinusoidal terms, mainly due to the intrinsic variation of the
primary, and the eclipse light-curve. New radial-velocity observations are
presented and used to compute parameters of a spectroscopic orbit. Frequency
analysis of the radial-velocity residuals from the spectroscopic orbital
solution fails to uncover periodic variations with amplitudes greater than 2
km/s. A Rossiter-McLaughlin anomaly is detected from observations covering
ingress.
  From archival photometric indices and the revised Hipparcos parallax we
derive the primary's effective temperature, surface gravity, bolometric
correction, and the luminosity. An analysis of a high signal-to-noise
spectrogram yields the effective temperature and surface gravity in good
agreement with the photometric values. From the same spectrogram, we determine
the abundance of He, C, N, O, Ne, Mg, Al, Si, P, S, Cl, and Fe.
  The eclipse light-curve is solved by means of EBOP. For a range of mass of
the primary, a value of mean density, very nearly independent of assumed mass,
is computed from the parameters of the system. Contrary to a recent report,
this value is approximately equal to the mean density obtained from the star's
effective temperature and luminosity.
  Despite limited frequency resolution of the MOST data, we were able to
recover the closely-spaced SPB frequency quadruplet discovered from the ground
in 2002-2004. The other two SPB terms seen from the ground were also recovered.
Moreover, our analysis of the MOST data adds 15 low-amplitude SPB terms with
frequencies ranging from 0.109 c/d to 2.786 c/d.


title:
Semiclassical approximation solved by Monte Carlo as an efficient
  impurity solver for dynamical mean field theory and its cluster extensions

abstract:
  We propose that a combination of the semiclassical approximation with Monte
Carlo simulations can be an efficient and reliable impurity solver for
dynamical mean field theory equations and their cluster extensions with large
cluster sizes. In order to show the reliability of the method, we consider two
test cases: (i) the single-band Hubbard model within the dynamical cluster
approximation with 4- and 8-site clusters and (ii) the anisotropic two-orbital
Hubbard model with orbitals of different band width within the single-site
dynamical mean field theory. We compare our results with those obtained from
solving the dynamical mean field equations with continuous time and determinant
quantum Monte Carlo. In both test cases we observe reasonable values of the
metal-insulator critical interaction strength $U_c/t$ and, while some details
of the spectral functions cannot be captured by the semiclassical approximation
due to the freezing of dynamical fluctuations, the main features are reproduced
by the approach.


title: The SWAP test and the Hong-Ou-Mandel effect are equivalent

abstract:
  We show that the Hong-Ou-Mandel effect from quantum optics is equivalent to
the SWAP test, a quantum information primitive which compares two arbitrary
states. We first derive a destructive SWAP test that doesn't need the ancillary
qubit that appears in the usual quantum circuit. Then, we study the
Hong-Ou-Mandel effect for two photons meeting at a beam splitter and prove it
is, in fact, an optical implementation of the destructive SWAP test. This
result offers both an interesting simple realization of a powerful quantum
information primitive and an alternative way to understand and analyse the
Hong-Ou-Mandel effect.


title: Spherical representations of Lie supergroups

abstract:
  The classical Cartan-Helgason theorem characterises finite-dimensional
spherical representations of reductive Lie groups in terms of their highest
weights. We generalise the theorem to the case of a reductive symmetric
supergroup pair $(G,K)$ of even type. Along the way, we compute the
Harish-Chandra $c$-function of the symmetric superspace $G/K$. By way of an
application, we show that all spherical representations are self-dual in type
AIII|AIII.