title: Why, how and when MHD turbulence at low $Rm$ becomes three-dimensional

abstract:
  MHD turbulence at low Magnetic Reynolds number is experimentally investigated
by studying a liquid metal flow in a cubic domain. We focus on the mechanisms
that determine whether the flow is quasi-2D, 3D or in any intermediate state.
To this end, forcing is applied by injecting a DC current $I$ through one wall
of the cube only, to drive vortices spinning along the magnetic field.
Depending on the intensity of the externally applied magnetic field, these
vortices extend part or all of the way through the cube. Driving the flow in
this way allows us to precisely control not only the forcing intensity but also
its dimensionality. A comparison with the theoretical analysis of this
configuration singles out the influences of the walls and of the forcing on the
flow dimensionality, which is characterised in several ways. First, when
inertia drives three-dimensionality, the velocity near the wall where current
is injected scales as $U_b\sim I^{2/3}$. Second, when the distance $l_z$ over
which momentum diffuses under the action of the Lorentz force reaches the
channel width $h$, the velocity near the opposite wall $U_t$ follows a similar
law with a correction factor $(1-h/l_z)$. When $l_z<h$, by contrast, the
opposite wall has less influence on the flow and $U_t\sim I^{1/2}$. The central
role played by the ratio $l_z/h$ is confirmed by experimentally verifying
Sommeria & Moreau (1982)'s scaling $l_z\sim N^{1/2}$ ($N$ is the interaction
parameter) and finally, the nature of the three-dimensionality is further
clarified by distinguishing weak and strong three-dimensionalities. It is found
that both vanish only asymptotically in the limit $N\rightarrow\infty$. This
provides evidence that because of the no-slip walls, 1) the transition between
quasi-2D and 3D turbulence does not result from a global instability of the
flow, and 2) it doesn't occur simultaneously at all scales.


title: The impact of selection in the \Lambda-Wright-Fisher model

abstract:
  The purpose of this article is to study some asymptotic properties of the
\Lambda-Wright-Fisher process with selection. This process represents the
frequency of a disadvantaged allele. The resampling mechanism is governed by a
finite measure \Lambda on [0,1] and the selection by a parameter \alpha. When
the measure \Lambda verifies \int_0^1-\log(1-x)x^{-2} \Lambda(dx)<\infty, some
particular behaviours in the frequency of the allele can occur. The selection
coefficient \alpha may be large enough to compensate the random genetic drift.
In other words, for certain selection pressure, the disadvantaged allele will
vanish asymptotically. This phenomenon cannot occur in the classical
Wright-Fisher diffusion. We study the dual process of the \Lambda-Wright-Fisher
process with selection and prove this result through martingale arguments.


title: Twofold Transition in PT-Symmetric Coupled Oscillators

abstract:
  The inspiration for this theoretical paper comes from recent experiments on a
PT-symmetric system of two coupled optical whispering galleries (optical
resonators). The optical system can be modeled as a pair of coupled linear
oscillators, one with gain and the other with loss. If the coupled oscillators
have a balanced loss and gain, the system is described by a Hamiltonian and the
energy is conserved. This theoretical model exhibits two PT transitions
depending on the size of the coupling parameter \epsilon. For small \epsilon
the PT symmetry is broken and the system is not in equilibrium, but when
\epsilon becomes sufficiently large, the system undergoes a transition to an
equilibrium phase in which the PT symmetry is unbroken. For very large \epsilon
the system undergoes a second transition and is no longer in equilibrium. The
classical and the quantized versions of the system exhibit transitions at
exactly the same values of \epsilon.


title: Response of Two-dimensional Kinetic Ising Model under Stochastic Field

abstract:
  We study, using Monte Carlo dynamics, the time ($t$) dependent average
magnetization per spin $m(t)$ behavior of 2-D kinetic Ising model under a
binary ($\pm h_0$) stochastic field $h(t)$. The time dependence of the
stochastic field is such that its average over each successive time interval
$\tau$ is assured to be zero (without any fluctuation). The average
magnetization $Q=(1/\tau)\int_{0}^{\tau} m(t) dt$ is considered as order
parameter of the system. The phase diagram in ($h_0,\tau$) plane is obtained.
Fluctuations in order parameter and their scaling properties are studied across
the phase boundary. These studies indicate that the nature of the transition is
Ising like (static Ising universality class) for field amplitudes $h_0$ below
some threshold value $h_0^c(\tau)$ (dependent on $\tau$ values;
$h_0^c\rightarrow0$ as $\tau\rightarrow\infty$ across the phase boundary) .
Beyond these $h_0^c (\tau)$, the transition is no longer continuous.


title:
Sharp endpoint results for imaginary powers and Riesz transforms on
  certain noncompact manifolds

abstract:
  In this paper we consider a complete connected noncompact Riemannian manifold
M with bounded geometry and spectral gap. We prove that the imaginary powers of
the Laplacian and the Riesz transform are bounded from the Hardy space X^1(M),
introduced in previous work of the authors, to L^1(M).


title:
Floquet theory based on new periodicity concept for hybrid systems
  involving $q$-difference equations

abstract:
  Using the new periodicity concept based on shifts, we construct a unified
Floquet theory for homogeneous and nonhomogeneous hybrid periodic systems on
domains having continuous, discrete or hybrid structure. New periodicity
concept based on shifts enables the construction of Floquet theory on hybrid
domains that are not necessarily additive periodic. This makes periodicity and
stability analysis of hybrid periodic systems possible on non-additive domains.
In particular, this new approach can be useful to know more about Floquet
theory for linear $q$-difference systems defined on
$\overline{q^{\mathbb{Z}}}:=\{q^{n}% :n\in\mathbb{Z}\} \cup \{0\}$ where $q>1$.
By constructing the solution of matrix exponential equation we establish a
canonical Floquet decomposition theorem. Determining the relation between
Floquet multipliers and Floquet exponents, we give a spectral mapping theorem
on closed subsets of reals that are periodic in shifts. Finally, we show how
the constructed theory can be utilized for the stability analysis of dynamic
systems on periodic time scales in shifts.


title: Test cost and misclassification cost trade-off using reframing

abstract:
  Many solutions to cost-sensitive classification (and regression) rely on some
or all of the following assumptions: we have complete knowledge about the cost
context at training time, we can easily re-train whenever the cost context
changes, and we have technique-specific methods (such as cost-sensitive
decision trees) that can take advantage of that information. In this paper we
address the problem of selecting models and minimising joint cost (integrating
both misclassification cost and test costs) without any of the above
assumptions. We introduce methods and plots (such as the so-called JROC plots)
that can work with any off-the-shelf predictive technique, including ensembles,
such that we reframe the model to use the appropriate subset of attributes (the
feature configuration) during deployment time. In other words, models are
trained with the available attributes (once and for all) and then deployed by
setting missing values on the attributes that are deemed ineffective for
reducing the joint cost. As the number of feature configuration combinations
grows exponentially with the number of features we introduce quadratic methods
that are able to approximate the optimal configuration and model choices, as
shown by the experimental results.


title: Low Polynomial Exclusion of Planar Graph Patterns

abstract:
  The celebrated grid exclusion theorem states that for every $h$-vertex planar
graph $H$, there is a constant $c_{h}$ such that if a graph $G$ does not
contain $H$ as a minor then $G$ has treewidth at most $c_{h}$. We are looking
for patterns of $H$ where this bound can become a low degree polynomial. We
provide such bounds for the following parameterized graphs: the wheel
($c_{h}=O(h)$), the double wheel ($c_{h}=O(h^2\cdot \log^{2} h)$), any graph of
pathwidth at most 2 ($c_{h}=O(h^{2})$), and the yurt graph ($c_{h}=O(h^{4})$).


title:
Search for cold and hot gas in the ram pressure stripped Virgo dwarf
  galaxy IC3418

abstract:
  We present IRAM 30m sensitive upper limits on CO emission in the ram pressure
stripped dwarf Virgo galaxy IC3418 and in a few positions covering HII regions
in its prominent 17 kpc UV/Ha gas-stripped tail. In the central few arcseconds
of the galaxy, we report a possible marginal detection of about 1x10^6 M_sun of
molecular gas (assuming a Galactic CO-to-H_2 conversion factor) that could
correspond to a surviving nuclear gas reservoir. We estimate that there is less
molecular gas in the main body of IC3418, by at least a factor of 20, than
would be expected from the pre-quenching UV-based star formation rate assuming
the typical gas depletion timescale of 2 Gyr. Given the lack of star formation
in the main body, we think the H_2-deficiency is real, although some of it may
also arise from a higher CO-to-H_2 factor typical in low-metallicity, low-mass
galaxies. The presence of HII regions in the tail of IC3418 suggests that there
must be some dense gas; however, only upper limits of < 1x10^6 M_sun were found
in the three observed points in the outer tail. This yields an upper limit on
the molecular gas content of the whole tail < 1x10^7 M_sun, which is an amount
similar to the estimates from the observed star formation rate over the tail.
We also present strong upper limits on the X-ray emission of the stripped gas
in IC3418 from a new Chandra observation. The measured X-ray luminosity of the
IC3418 tail is about 280 times lower than that of ESO 137-001, a spiral galaxy
in a more distant cluster with a prominent ram pressure stripped tail.
Non-detection of any diffuse X-ray emission in the IC3418 tail may be due to a
low gas content in the tail associated with its advanced evolutionary state
and/or due to a rather low thermal pressure of the surrounding intra-cluster
medium.


title:
Temporal Locality in Today's Content Caching: Why it Matters and How to
  Model it

abstract:
  The dimensioning of caching systems represents a difficult task in the design
of infrastructures for content distribution in the current Internet. This paper
addresses the problem of defining a realistic arrival process for the content
requests generated by users, due its critical importance for both analytical
and simulative evaluations of the performance of caching systems. First, with
the aid of YouTube traces collected inside operational residential networks, we
identify the characteristics of real traffic that need to be considered or can
be safely neglected in order to accurately predict the performance of a cache.
Second, we propose a new parsimonious traffic model, named the Shot Noise Model
(SNM), that enables users to natively capture the dynamics of content
popularity, whilst still being sufficiently simple to be employed effectively
for both analytical and scalable simulative studies of caching systems.
Finally, our results show that the SNM presents a much better solution to
account for the temporal locality observed in real traffic compared to existing
approaches.


title:
Strain evolution in GaN Nanowires: from free-surface objects to
  coalesced templates

abstract:
  Top-down fabricated GaN nanowires, 250 nm in diameter and with various
heights, have been used to experimentally determine the evolution of strain
along the vertical direction of 1-dimensional objects. X-ray diffraction and
photoluminescence techniques have been used to obtain the strain profile inside
the nanowires from their base to their top facet for both initial compressive
and tensile strains. The relaxation behaviors derived from optical and
structural characterizations perfectly match the numerical results of
calculations based on a continuous media approach. By monitoring the elastic
relaxation enabled by the lateral free-surfaces, the height from which the
nanowires can be considered strain-free has been estimated. Based on this
result, NWs sufficiently high to be strain-free have been coalesced to form a
continuous GaN layer. X-ray diffraction, photoluminescence and
cathodoluminescence clearly show that despite the initial strain-free nanowires
template, the final GaN layer is strained.


title: Weyl transformations and trace anomalies in N=1, D=4 supergravities

abstract:
  We identify the supersymmetric extension of Weyl transformations in various
types of supergravities, the minimal, nonminimal and new minimal N=1 SUGRA in
4D, formulated in terms of superfields. Based also on previous results we
conclude that there are only two types of trace anomalies in nonminimal and new
minimal supergravities, which correspond to the two nontrivial cocycles of the
minimal supergravity and, when reduced to component form, to the well-known
squared Weyl density and Euler density. There are nevertheless in new minimal
supergravity other nontrivial cocycles which, however, are mapped to zero in
the minimal supergravity.


title:
Adaptation and optimization of synchronization gains in networked
  distributed parameter systems

abstract:
  This work is concerned with the design and effects of the synchronization
gains on the synchronization problem for a class of networked distributed
parameter systems. The networked systems, assumed to be described by the same
evolution equation in a Hilbert space, differ in their initial conditions. The
proposed synchronization controllers aim at achieving both the control
objective and the synchronization objective. To enhance the synchronization, as
measured by the norm of the pairwise state difference of the networked systems,
an adaptation of the gains is proposed. An alternative design arrives at
constant gains that are optimized with respect to an appropriate measure of
synchronization. A subsequent formulation casts the control and synchronization
design problem into an optimal control problem for the aggregate systems. An
extensive numerical study examines the various aspects of the optimization and
adaptation of the gains on the control and synchronization of networked 1D
parabolic differential equations.


title: Rotation-managed dissipative solitons

abstract:
  We show that when spatially localized gain landscape performs accelerated
motion in the transverse plane, i.e., when it rotates or oscillates around the
light propagation axis, the effective gain experienced by the light beam
considerably reduces with increase of the amplitude of oscillations or
frequency of rotation of the localized gain. In the presence of uniform
background losses and defocusing nonlinearity, such gain landscapes may support
dynamically oscillating gain-managed solitons, but if the amplitude of
oscillations or the frequency of rotation of the localized gain exceeds a
threshold, stable attractors disappear and any input beam decays.


title: Giant pressure-induced volume collapse in the pyrite mineral MnS2

abstract:
  Dramatic volume collapses under pressure are fundamental to geochemistry and
of increasing importance to fields as diverse as hydrogen storage and
high-temperature superconductivity. In transition metal materials, collapses
are usually driven by so-called spin-state transitions, the interplay between
the single-ion crystal field and the size of the magnetic moment. Here we show
that the classical S=5/2 mineral Hauerite undergoes an unprecedented 22 %
collapse driven by a conceptually different magnetic mechanism. Using
synchrotron x-ray diffraction we show that cold compression induces the
formation of a disordered intermediate. However, using an evolutionary
algorithm we predict a new structure with edge-sharing chains. This is
confirmed as the thermodynamic groundstate using in situ laser heating. We show
that magnetism is globally absent in the new phase, as low-spin quantum S=1/2
moments are quenched by dimerisation. Our results show how the emergence of
metal-metal bonding can stabilise giant spin-lattice coupling in Earth's
minerals.


title: Computations by fly-automata beyond monadic second-order logic

abstract:
  We present logically based methods for constructing XP and FPT graph
algorithms, parametrized by tree-width or clique-width. We will use
fly-automata introduced in a previous article. They make possible to check
properties that are not monadic second-order expressible because their states
may include counters, so that their sets of states may be infinite. We equip
these automata with output functions, so that they can compute values
associated with terms or graphs. Rather than new algorithmic results we present
tools for constructing easily certain dynamic programming algorithms by
combining predefined automata for basic functions and properties.


title:
Regression techniques for subspace-based black-box state-space system
  identification: an overview

abstract:
  As far as the identification of linear time-invariant state-space
representation is concerned, among all of the solutions available in the
literature, the subspace-based state-space model identification techniques have
proved their efficiency in many practical cases since the beginning of the
90's. This paper introduces an overview of these techniques by focusing on
their formulation as a least-squares problem. Apart from an article written by
J. Qin, to the author's knowledge, such a regression formulation is not totally
investigated in the books which can be considered as the references as far as
subspace-based identification is concerned. Thus, in this paper, a specific
attention is payed to the regression-based techniques used to identify systems
working under open-loop as well as closed-loop conditions.


title: Nonlocal refuge model with a partial control

abstract:
  In this paper, we analyse the structure of the set of positive solutions of
an heterogeneous nonlocal equation of the form: $$ \int_{\Omega} K(x,
y)u(y)\,dy -\int_ {\Omega}K(y, x)u(x)\, dy + a_0u+\lambda a_1(x)u
-\beta(x)u^p=0 \quad \text{in}\quad \times \O$$ where $\Omega\subset \R^n$ is a
bounded open set, $K\in C(\R^n\times \R^n) $ is nonnegative, $a_i,\beta \in
C(\Omega)$ and $\lambda\in\R$. Such type of equation appears in some studies of
population dynamics where the above solutions are the stationary states of the
dynamic of a spatially structured population evolving in a heterogeneous
partially controlled landscape and submitted to a long range dispersal. Under
some fairly general assumptions on $K,a_i$ and $\beta$ we first establish a
necessary and sufficient criterium for the existence of a unique positive
solution. Then we analyse the structure of the set of positive solution
$(\lambda,u_\lambda)$ with respect to the presence or absence of a refuge zone
(i.e $\omega$ so that $\beta_{|\omega}\equiv 0$).


title:
First-Principles Theory of Anharmonicity and the Inverse Isotope Effect
  in Superconducting Palladium-Hydride Compounds

abstract:
  Palladium hydrides display the largest isotope effect anomaly known in
literature. Replacement of hydrogen with the heavier isotopes leads to higher
superconducting temperatures, a behavior inconsistent with harmonic theory.
Solving the self-consistent harmonic approximation by a stochastic approach, we
obtain the anharmonic free energy, the thermal expansion and the
superconducting properties fully ab initio. We find that the phonon spectra are
strongly renormalized by anharmonicity far beyond the perturbative regime.
Superconductivity is phonon mediated, but the harmonic approximation largely
overestimates the superconducting critical temperatures. We explain the inverse
isotope effect, obtaining a -0.38 value for the isotope coefficient in good
agreement with experiments, hydrogen anharmonicity being the main responsible
for the isotope anomaly.


title: Self-organized dynamics in local load sharing fiber bundle models

abstract:
  We study the dynamics of a local load sharing fiber bundle model in two
dimensions, under an external load (which increases with time at a fixed slow
rate) applied at a single point. Due to the local load sharing nature, the
redistributed load remains localized along the boundary of the broken patch.
The system then goes to a self-organized state with a stationary average value
of load per fiber along the (increasing) boundary of the broken patch (damaged
region) and a scale free distribution of avalanche sizes and other related
quantities are observed. In particular, when the load redistribution is only
among nearest surviving fiber(s), the numerical estimates of the exponent
values are comparable with those of the Manna model. When the load
redistribution is uniform along the patch boundary, the model shows a simple
mean-field limit of this self-organizing critical behaviour, for which we give
analytical estimates of the saturation load per fiber values and avalanche size
distribution exponent. These are in good agreement with numerical simulation
results.


title:
Continuous Dynamic Photostimulation - inducing in-vivo-like fluctuating
  conductances with Channelrhodopsins

abstract:
  Central neurons operate in a regime of constantly fluctuating conductances,
induced by thousands of presynaptic cells. Channelrhodopsins have been almost
exclusively used to imprint a fixed spike pattern by sequences of brief
depolarizations. Here we introduce continuous dynamic photostimulation
(CoDyPs), a novel approach to mimic in-vivo like input fluctuations
noninvasively in cells transfected with the weakly inactivating
channelrhodopsin variant ChIEF. Even during long-term experiments, cultured
neurons subjected to CoDyPs generate seemingly random, but reproducible spike
patterns. In voltage clamped cells CoDyPs induced highly reproducible current
waveforms that could be precisely predicted from the light-conductance transfer
function of ChIEF. CoDyPs can replace the conventional, flash-evoked imprinting
of spike patterns in in-vivo and in-vitro studies, preserving natural activity.
When combined with non-invasive spike-detection, CoDyPs allows the acquisition
of order of magnitudes larger data sets than previously possible, for studies
of dynamical response properties of many individual neurons.


title: Out of equilibrium dynamics of classical and quantum complex systems

abstract:
  Equilibrium is a rather ideal situation, the exception rather than the rule
in Nature. Whenever the external or internal parameters of a physical system
are varied its subsequent relaxation to equilibrium may be either impossible or
take very long times. From the point of view of fundamental physics no generic
principle such as the ones of thermodynamics allows us to fully understand
their behaviour. The alternative is to treat each case separately. It is
illusionary to attempt to give, at least at this stage, a complete description
of all non-equilibrium situations. Still, one can try to identify and
characterise some concrete but still general features of a class of out of
equilibrium problems - yet to be identified - and search for a unified
description of these. In this report I briefly describe the behaviour and
theory of a set of non-equilibrium systems and I try to highlight common
features and some general laws that have emerged in recent years.


title:
Results on modelling and products of singularities in Colombeau algebra
  G(R)

abstract:
  Modelling of singularities given by discontinuous functions or distributions
by means of generalized functions has proved useful in many problems posed by
physical phenomena. We introduce in a systematic way generalized functions of
Colombeau that model such singularities. Moreover, we evaluate some products of
singularity-modelling generalized functions whenever the result admits an
associated distribution


title: Adaptive Alert Throttling for Intrusion Detection Systems

abstract:
  Each time that an intrusion detection system raises an alert it must make
some attempt to communicate the information to an operator. This communication
channel can easily become the target of a denial of service attack because,
like all communication channels, it has a fixed capacity. If this channel can
become overwhelmed with bogus data, an attacker can quickly achieve complete
neutralisation of intrusion detection capability. Although these types of
attack are very hard to stop completely, our aim is to present techniques that
improve alert throughput and capacity to such an extent that the resources
required to successfully mount the attack become prohibitive.


title: Resonant effects in random dielectric structures

abstract:
  Recently, a theory for artificial magnetism in two-dimensional photonic
crystals has been developed for large wavelength using homogenization
techniques. In this paper we pursue this approach within a rigorous stochastic
framework: dielectric parallel nanorods are randomly disposed, each of them
having, up to a large scaling factor, a random permittivity \epsilon(\omega)
whose law is represented by a density on a window \Delta=[a,b]x[0,h] of the
complex plane. We give precise conditions on the initial probability law
(permittivity, radius and position of the rods) under which the homogenization
process can be performed leading to a deterministic dispersion law for the
effective permeability with possibly negative real part.
  Subsequently a limit analysis h->0, accounting a density law of \epsilon,
which concentrates on the real axis, reveals singular behavior due to the
presence of resonances in the microstructure.


title: Memory Implementations - Current Alternatives

abstract:
  Memory can be defined as the ability to retain and recall information in a
diverse range of forms. It is a vital component of the way in which we as human
beings operate on a day to day basis. Given a particular situation, decisions
are made and actions undertaken in response to that situation based on our
memory of related prior events and experiences. By utilising our memory we can
anticipate the outcome of our chosen actions to avoid unexpected or unwanted
events. In addition, as we subtly alter our actions and recognise altered
outcomes we learn and create new memories, enabling us to improve the
efficiency of our actions over time. However, as this process occurs so
naturally in the subconscious its importance is often overlooked.


title: Efficient, Tightly-Confined Trapping of 226Ra

abstract:
  We demonstrate a technique for transferring $^{226}$Ra atoms from a
3-dimensional magneto-optical-trap (MOT) into a standing wave optical dipole
trap (ODT) in an adjacent chamber. The resulting small trapping volume (120
$\mu$m in diameter) allows for high control of the electric and magnetic fields
applied to the atoms. The atoms are first transferred to a traveling-wave
optical dipole trap, which is then translated 46 cm to a science chamber. The
atoms are subsequently transferred into an orthogonal standing-wave ODT by
application of a 1-dimensional MOT along the traveling-wave axis. For each
stage, transfer efficiencies exceeding 60% are demonstrated.


title: Analytical shock solutions at large and small Prandtl number

abstract:
  Exact one-dimensional solutions to the equations of fluid dynamics are
derived in the large-Pr and small-Pr limits (where Pr is the Prandtl number).
The solutions are analogous to the Pr = 3/4 solution discovered by Becker and
analytically capture the profile of shock fronts in ideal gases. The large-Pr
solution is very similar to Becker's solution, differing only by a scale
factor. The small-Pr solution is qualitatively different, with an embedded
isothermal shock occurring above a critical Mach number. Solutions are derived
for constant viscosity and conductivity as well as for the case in which
conduction is provided by a radiation field. For a completely general density-
and temperature-dependent viscosity and conductivity, the system of equations
in all three limits can be reduced to quadrature. The maximum error in the
analytical solutions when compared to a numerical integration of the finite-Pr
equations is O(1/Pr) for large Pr and O(Pr) for small Pr.


title:
Optical Detection of Single Nanoparticles with a Sub-wavelength
  Fiber-Taper

abstract:
  A nanoparticle detection scheme with single particle resolution is presented.
The sensor contains only a taper fiber thus offering the advantages of
compactness and installation flexibility. Sensing method is based on monitoring
the transmitted light power which shows abrupt jumps with each particle binding
to the taper surface. The experimental validation of the sensor is demonstrated
with polystyrene nanoparticles of radii 120 nm and 175 nm in the 1550 nm
wavelength band.


title:
Dependence of acoustic surface gravity on geometric configuration of
  matter for axially symmetric background flows in the Schwarzschild metric ~

abstract:
  In black hole evaporation process, the mass of the hole anti-correlates with
the Hawking temperature. This indicates that the smaller holes have higher
surface gravity. For analogue Hawking effects, however, the acoustic surface
gravity is determined by the local values of the dynamical velocity of the
stationary background fluid flow and the speed of propagation of the
characteristic perturbation embedded in the background fluid, as well as by
their space derivatives evaluated along the direction normal to the acoustic
horizon, respectively. The mass of the analogue system - whether classical or
quantum - does not directly contribute to extremise the value of the associated
acoustic surface gravity. For general relativistic axially symmetric background
fluid flow in the Schwarzschild metric, we show that the initial boundary
conditions describing such accretion influence the maximization scheme of the
acoustic surface gravity and associated analogue temperature. Aforementioned
background flow onto black holes can assume three distinct geometric
configurations. Identical set of initial boundary conditions can lead to
entirely different phase-space behavior of the stationary flow solutions, as
well as the salient features of the associated relativistic acoustic geometry.
This implies that it is imperative to investigate how the measure of the
acoustic surface gravity corresponding to the accreting black holes gets
influenced by the geometric configuration of the inflow described by various
thermodynamic equations of state. Such investigation is useful to study the
effect of Einstenian gravity on the non-conventional classical features as
observed in Hawking like effect in a dispersive medium in the limit of a strong
dispersion relation.


title:
Input-output theory for waveguide QED with an ensemble of inhomogeneous
  atoms

abstract:
  We study the collective effects that emerge in waveguide quantum
electrodynamics where several (artificial) atoms are coupled to a
one-dimensional superconducting transmission line. Since single microwave
photons can travel without loss for a long distance along the line, real and
virtual photons emitted by one atom can be reabsorbed or scattered by a second
atom. Depending on the distance between the atoms, this collective effect can
lead to super- and subradiance or to a coherent exchange-type interaction
between the atoms. Changing the artificial atoms transition frequencies,
something which can be easily done with superconducting qubits (two levels
artificial atoms), is equivalent to changing the atom-atom separation and
thereby opens the possibility to study the characteristics of these collective
effects. To study this waveguide quantum electrodynamics system, we extend
previous work and present an effective master equation valid for an ensemble of
inhomogeneous atoms driven by a coherent state. Using input-output theory, we
compute analytically and numerically the elastic and inelastic scattering and
show how these quantities reveal information about collective effects. These
theoretical results are compatible with recent experimental results using
transmon qubits coupled to a superconducting one-dimensional transmission line
[A.~F.~van Loo {\it et al.}].


title: Dynamical Mean Field Approximation Applied to Quantum Field Theory

abstract:
  We apply the Dynamical Mean Field (DMFT) approximation to the real, scalar
phi^4 quantum field theory. By comparing to lattice Monte Carlo calculations,
perturbation theory and standard mean field theory, we test the quality of the
approximation in two, three, four and five dimensions. The quantities
considered in these tests are the critical coupling for the transition to the
ordered phase and the associated critical exponents nu and beta. We also map
out the phase diagram in four dimensions. In two and three dimensions, DMFT
incorrectly predicts a first order phase transition for all bare quartic
couplings, which is problematic, because the second order nature of the phase
transition of lattice phi^4-theory is crucial for taking the continuum limit.
Nevertheless, by extrapolating the behaviour away from the phase transition,
one can obtain critical couplings and critical exponents. They differ from
those of mean field theory and are much closer to the correct values. In four
dimensions the transition is second order for small quartic couplings and turns
weakly first order as the coupling increases beyond a tricritical value. In
dimensions five and higher, DMFT gives qualitatively correct results, predicts
reasonable values for the critical exponents and considerably more accurate
critical couplings than standard mean field theory. The approximation works
best for small values of the quartic coupling. We investigate the change from
first to second order transition in the local limit of DMFT which is
computationally much less intensive. We also discuss technical issues related
to the convergence of the non-linear self-consistency equation solver and the
solution of the effective single-site model using Fourier-space Monte Carlo
updates in the presence of a phi^4-interaction.


title: Modeling the Infrared Extinction toward the Galactic Center

abstract:
  We model the ~1--19$\mum$ infrared (IR) extinction curve toward the Galactic
Center (GC) in terms of the standard silicate-graphite interstellar dust model.
The grains are taken to have a power law size distribution with an exponential
decay above some size. The best-fit model for the GC IR extinction constrains
the visual extinction to be Av~38--42 mag. The limitation of the model, i.e.,
its difficulty in simultaneously reproducing both the steep ~1--3$\mum$ near-IR
extinction and the flat ~3--8$\mum$ mid-IR extinction is discussed. We argue
that this difficulty could be alleviated by attributing the extinction toward
the GC to a combination of dust in different environments: dust in diffuse
regions (characterized by small Rv and steep near-IR extinction), and dust in
dense regions (characterized by large Rv and flat UV extinction).


title: Helical liquid of snake states

abstract:
  We derive an exact solution to the problem of spin snake states induced in a
nonhomogeneous magnetic field by a combined action of the Rashba spin-orbit and
Zeeman fields. In an antisymmetric magnetic field the spin snake states are
nonlocal composite particles, originating from spatially separated entangled
spins. Adding an external homogeneous magnetic field breaks the spin-parity
symmetry gapping out the spectral branches, which results in a regular beating
pattern of the spin current. These new phenomena in a helical liquid of snake
states are proposed for an experimental realization.


title:
Violation of the FRW consistency condition as a signature of
  backreaction

abstract:
  We propose a backreaction toy model with realistic features and confront it
with the Union2.1 supernova data. The model provides a good fit even though the
expansion history is quite different from the LCDM model and the effective
equation of state is far from -1. We discuss compatibility (or lack thereof)
with other observations. We show that the FRW consistency condition between
distance and expansion rate is violated with an amplitude that is slightly
below the current observational limits. We expect that this is also the case in
the real universe if backreaction is significant, providing a distinct
signature of backreaction.


title:
Axial symmetry breaking in self-induced flavor conversion of supernova
  neutrino fluxes

abstract:
  Neutrino-neutrino refraction causes self-induced flavor conversion in dense
neutrino fluxes. For the first time, we include the azimuth angle of neutrino
propagation as an explicit variable and find a new generic multi-azimuth-angle
(MAA) instability which, for simple spectra, occurs in the normal neutrino mass
hierarchy. Matter suppression of this instability in supernovae requires larger
densities than the traditional bimodal case. The new instability shows
explicitly that solutions of the equations for collective flavor oscillations
need not inherit the symmetries of initial or boundary conditions. This change
of paradigm requires reconsideration of numerous results in this field.


title:
Possible measurable effects of light propagating in electromagnetized
  vacuum, as predicted by a scalar tensor theory of gravitation

abstract:
  The effect of static electromagnetic fields on the propagation of light is
analyzed in the context of a particular class of scalar-tensor gravitational
theories. It is found that for appropriate field configurations and light
polarization, anomalous amplitude variations of the light as it propagates in
either a magnetized or electrified vacuum are strong enough to be detectable in
relatively simple laboratory experiments.


title: Observing light-by-light scattering at the Large Hadron Collider

abstract:
  Elastic light-by-light scattering, $\gamma\gamma\to\gamma\gamma$, is open to
study at the Large Hadron Collider thanks to the large quasi-real photon fluxes
available in electromagnetic interactions of protons (p) and lead (Pb) ions.
The $\gamma\gamma\to\gamma\gamma$ cross sections for diphoton masses
$m_{\gamma\gamma} > 5$ GeV amount to 105 fb, 260 pb, and 370 nb in p-p, p-Pb,
and Pb-Pb collisions at nucleon-nucleon center-of-mass energies $\sqrt{s_{NN}}$
= 14 TeV, 8.8 TeV, and 5.5 TeV respectively. Such a measurement has no
substantial backgrounds in Pb-Pb collisions where one expects about 70 signal
events per run, after typical detector acceptance and reconstruction efficiency
selections.


title: The EMC effect still puzzles after 30 years

abstract:
  Thirty years ago, high-energy muons at CERN revealed the first hints of an
effect that puzzles experimentalists and theorists alike to this day.


title: Immune System Approaches to Intrusion Detection - A Review (ICARIS)

abstract:
  The use of artificial immune systems in intrusion detection is an appealing
concept for two reasons. Firstly, the human immune system provides the human
body with a high level of protection from invading pathogens, in a robust,
self-organised and distributed manner. Secondly, current techniques used in
computer security are not able to cope with the dynamic and increasingly
complex nature of computer systems and their security. It is hoped that
biologically inspired approaches in this area, including the use of
immune-based systems will be able to meet this challenge. Here we collate the
algorithms used, the development of the systems and the outcome of their
implementation. It provides an introduction and review of the key developments
within this field, in addition to making suggestions for future research.


title: Modelling and Analysing Cargo Screening Processes: A Project Outline

abstract:
  The efficiency of current cargo screening processes at sea and air ports is
unknown as no benchmarks exists against which they could be measured. Some
manufacturer benchmarks exist for individual sensors but we have not found any
benchmarks that take a holistic view of the screening procedures assessing a
combination of sensors and also taking operator variability into account. Just
adding up resources and manpower used is not an effective way for assessing
systems where human decision-making and operator compliance to rules play a
vital role. For such systems more advanced assessment methods need to be used,
taking into account that the cargo screening process is of a dynamic and
stochastic nature. Our project aim is to develop a decision support tool
(cargo-screening system simulator) that will map the right technology and
manpower to the right commodity-threat combination in order to maximize
detection rates. In this paper we present a project outline and highlight the
research challenges we have identified so far. In addition we introduce our
first case study, where we investigate the cargo screening process at the ferry
port in Calais.


title:
"You Know Because I Know": a Multidimensional Network Approach to Human
  Resources Problem

abstract:
  Finding talents, often among the people already hired, is an endemic
challenge for organizations. The social networking revolution, with online
tools like Linkedin, made possible to make explicit and accessible what we
perceived, but not used, for thousands of years: the exact position and ranking
of a person in a network of professional and personal connections. To search
and mine where and how an employee is positioned on a global skill network will
enable organizations to find unpredictable sources of knowledge, innovation and
know-how. This data richness and hidden knowledge demands for a
multidimensional and multiskill approach to the network ranking problem.
Multidimensional networks are networks with multiple kinds of relations. To the
best of our knowledge, no network-based ranking algorithm is able to handle
multidimensional networks and multiple rankings over multiple attributes at the
same time. In this paper we propose such an algorithm, whose aim is to address
the node multi-ranking problem in multidimensional networks. We test our
algorithm over several real world networks, extracted from DBLP and the Enron
email corpus, and we show its usefulness in providing less trivial and more
flexible rankings than the current state of the art algorithms.


title: Cell Growth and Size Homeostasis in Silico

abstract:
  Cell growth in size is a complex process coordinated by intrinsic and
environmental signals. In a recent work [Tzur et al., Science, 2009,
325:167-171], size distributions in an exponentially growing population of
mammalian cells were used to infer the growth rate in size. The results suggest
that cell growth is neither linear nor exponential, but subject to
size-dependent regulation. To explain their data, we build a model in which the
cell growth rate is controlled by the relative amount of mRNA and ribosomes in
a cell. Plus a stochastic division rule, the evolutionary process of a
population of cells can be simulated and the statistics of the in-silico
population agree well with the experimental data. To further explore the model
space, alternative growth models and division rules are studied. This work may
serve as a starting point for us to understand the rational behind cell growth
and size regulation using predictive models.


title:
Uniqueness for continuity equations in Hilbert spaces with weakly
  differentiable drift

abstract:
  We prove uniqueness for continuity equations in Hilbert spaces $H$. The
corresponding drift $F$ is assumed to be in a first order Sobolev space with
respect to some Gaussian measure. As in previous work on the subject, the proof
is based on commutator estimates which are infinite dimensional analogues to
the classical ones due to DiPerna-Lions. Our general approach is, however,
quite different since, instead of considering renormalized solutions, we prove
a dense range condition implying uniqueness. In addition, compared to known
results by Ambrosio-Figalli and Fang-Luo, we use a different approximation
procedure, based on a more regularizing Ornstein-Uhlenbeck semigroup and
consider Sobolev spaces of vector fields taking values in $H$ rather than the
Cameron-Martin space of the Gaussian measure. This leads to different
conditions on the derivative of $F$, which are incompatible with previous work
on the subject. Furthermore, we can drop the usual exponential integrability
conditions on the Gaussian divergence of $F$, thus improving known uniqueness
results in this respect.


title: Image simulation for biological microscopy: microlith

abstract:
  Image simulation remains under-exploited for the most widely used biological
phase microscopy methods, because of difficulties in simulating partially
coherent illumination. We describe an open-source toolbox, microlith
(https://code.google.com/p/microlith), which accurately predicts
three-dimensional images of a thin specimen observed with any partially
coherent imaging system, including coherently illuminated and incoherent,
self-luminous specimens. Its accuracy is demonstrated by comparing simulated
and experimental bright-field and dark-field images of well-characterized
amplitude and phase targets, respectively. The comparison provides new insights
about the sensitivity of the dark-field microscope to mass distributions in
isolated or periodic specimens at the length-scale of 10nm. Based on
predictions using microlith, we propose a novel approach for detecting
nanoscale structural changes in a beating axoneme using a dark-field
microscope.


title:
Hilbert-Schmidt Hankel Operators with Anti-holomorphic Symbols on
  Complex Ellipsoids

abstract:
  On a complex ellipsoid in $\mathbb{C}^n$, we show that there is no nonzero
Hankel operator with an anti-holomorphic symbol that is Hilbert-Schmidt.


title: Inflationary Magnetogenesis without the Strong Coupling Problem

abstract:
  The simplest gauge invariant models of inflationary magnetogenesis are known
to suffer from the problems of either large backreaction or strong coupling,
which make it difficult to self-consistently achieve cosmic magnetic fields
from inflation with a field strength larger than $10^{-32} G$ today on the
$\Mpc$ scale. Such a strength is insufficient to act as seed for the galactic
dynamo effect, which requires a magnetic field larger than $10^{-20} G$. In
this paper we analyze simple extensions of the minimal model, which avoid both
the strong coupling and back reaction problems, in order to generate
sufficiently large magnetic fields on the Mpc scale today. First we study the
possibility that the coupling function which breaks the conformal invariance of
electromagnetism is non-monotonic with sharp features. Subsequently, we
consider the effect of lowering the energy scale of inflation jointly with a
scenario of prolonged reheating where the universe is dominated by a stiff
fluid for a short period after inflation. In the latter case, a systematic
study shows upper bounds for the magnetic field strength today on the Mpc scale
of $10^{-13} G$ for low scale inflation and $10^{-25} G$ for high scale
inflation, thus improving on the previous result by 7-19 orders of magnitude.
These results are consistent with the strong coupling and back reaction
constraints.


title:
About the linearity of the color-magnitude relation of early-type
  galaxies in the Virgo cluster

abstract:
  We revisit the color-magnitude relation (CMR) of the Virgo cluster early-type
galaxies in order to explore its alleged non-linearity. To this aim, we
reanalyze the relation already published from data obtained within the ACS
Virgo Cluster Survey of the Hubble Space Telescope, and perform our own
photometry and analysis of the images of the 100 early-type galaxies observed
as part of this survey. In addition, we compare our results with those reported
in the literature from data of the Sloan Digital Sky Survey. We have found that
when the brightest galaxies and untypical systems are excluded from the sample,
a linear relation arises in agreement with what is observed in other groups and
clusters. The central regions of the brightest galaxies also follow this
relation. In addition, we notice that Virgo contains at least four compact
elliptical galaxies besides the well known object VCC 1297 (NGC 4486B). Their
locations in the <mueff>-luminosity diagram define a different trend to that
followed by normal early-type dwarf galaxies, setting an upper limit in
effective surface brightness and a lower limit in effective radius for their
luminosities. Based on the distribution of different galaxy sub-samples in the
color-magnitude and <mueff>-luminosity diagrams we draw some conclusions on
their formation and the history of their evolution.


title: Further Estimates with Pseudogamma functions

abstract:
  The pseudo-Gamma function is a key tool introduced recently by Cheng and
Albeverio in the proof of \break the density hypothesis. This function is
doubly symmetric, which means that it is reflectively symmetric about the real
axis by the Schwarz principle, whereas it is also reflectively symmmetric about
the half line where the real part of the variable is equal to $\tfrac{1}{2}$.
In this article, we sharpen the estimate given in the proof of the density
hypothesis for this doubly symmetric pseudo-Gamma function on the real axis
near the symmetry center by taking a different approach from the way used in
the density hypothesis proof directly from the definition, reducing the error
caused by the fact that the difference of two pivotal parameters in the
definition of the pseudo-Gamma function is much larger than the difference of
the variables in this particular case.


title: Colloquium: Understanding Quantum Weak Values: Basics and Applications

abstract:
  Since its introduction 25 years ago, the quantum weak value has gradually
transitioned from a theoretical curiosity to a practical laboratory tool. While
its utility is apparent in the recent explosion of weak value experiments, its
interpretation has historically been a subject of confusion. Here a pragmatic
introduction to the weak value in terms of measurable quantities is presented,
along with an explanation for how it can be determined in the laboratory.
Further, its application to three distinct experimental techniques is reviewed.
First, as a large interaction parameter it can amplify small signals above
technical background noise. Second, as a measurable complex value it enables
novel techniques for direct quantum state and geometric phase determination.
Third, as a conditioned average of generalized observable eigenvalues it
provides a measurable window into nonclassical features of quantum mechanics.
In this selective review, a single experimental configuration to discuss and
clarify each of these applications is used.


title:
Triggered fragmentation in gravitationally unstable discs: forming
  fragments at small radii

abstract:
  We carry out three dimensional radiation hydrodynamical simulations of
gravitationally unstable discs using to explore the movement of mass in a disc
following its fragmentation. Compared to a more quiescent state before it
fragments, the radial velocity of the gas increases by up to a factor of ~2-3
after fragmentation. While the mass movement occurs both inwards and outwards,
the inwards motion can cause the inner spirals to be sufficiently dense that
they may become unstable and potentially fragment. Consequently, the dynamical
behaviour of fragmented discs may cause subsequent fragmentation at smaller
radii after an initial fragment has formed in the outer disc.


title: Joint probability densities of level spacing ratios in random matrices

abstract:
  We calculate analytically, for finite-size matrices, joint probability
densities of ratios of level spacings in ensembles of random matrices
characterized by their associated confining potential. We focus on the ratios
of two spacings between three consecutive real eigenvalues, as well as certain
generalizations such as the overlapping ratios. The resulting formulas are
further analyzed in detail in two specific cases: the beta-Hermite and the
beta-Laguerre cases, for which we offer explicit calculations for small N. The
analytical results are in excellent agreement with numerical simulations of
usual random matrix ensembles, and with the level statistics of a quantum
many-body lattice model and zeros of the Riemann zeta function.

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


title: Quantum Phase Slips in one-dimensional Josephson Junction Chains

abstract:
  We have studied quantum phase-slip (QPS) phenomena in long one-dimensional
Josephson junction series arrays with tunable Josephson coupling. These chains
were fabricated with as many as 2888 junctions, where one sample had a tunable
weak link in the middle. Measurements were made of the zero-bias resistance,
$R_0$, as well as current-voltage characteristics (IVC). The finite $R_0$ is
explained by QPS and shows an exponential dependence on $\sqrt{E_J/E_C}$ with a
distinct change in the exponent at $R_0=R_Q=h/4e^2$. When $R_0 > R_Q$ the IVC
clearly shows a remnant of the Coulomb blockade, which evolves to a
zero-current state with a sharp critical voltage as $E_J$ is tuned to a smaller
value. The zero-current state below the critical voltage is due to coherent QPS
and we show that these are enhanced at the central weak link. Above the
critical voltage a negative differential resistance is observed which nearly
restores the zero-current state.


title:
Crossing pedestrian traffic flows,diagonal stripe pattern, and chevron
  effect

abstract:
  We study two perpendicular intersecting flows of pedestrians. The latter are
represented either by moving hard core particles of two types, eastbound
($\symbp$) and northbound ($\symbm$), or by two density fields, $\rhop_t(\brr)$
and $\rhom_t(\brr)$. Each flow takes place on a lattice strip of width $M$ so
that the intersection is an $M\times M$ square. We investigate the spontaneous
formation, observed experimentally and in simulations, of a diagonal pattern of
stripes in which alternatingly one of the two particle types dominates. By a
linear stability analysis of the field equations we show how this pattern
formation comes about. We focus on the observation, reported recently, that the
striped pattern actually consists of chevrons rather than straight lines. We
demonstrate that this `chevron effect' occurs both in particle simulations with
various different update schemes and in field simulations. We quantify the
effect in terms of the chevron angle $\Delta\theta_0$ and determine its
dependency on the parameters governing the boundary conditions.


title: Berezin transforms on noncommutative varieties in polydomains

abstract:
  In this paper, we study noncommutative varieties in polydomains in $B(H)^n$.
The goal is to understand the structure of these varieties, determine their
elements and classify them up to unitary equivalence. Using noncommutative
Berezin transforms associated with each variety, we develop an operator model
theory and dilation theory for large classes of varieties in noncommutative
polydomains. This includes various commutative cases which are close connected
to the theory of holomorphic functions in several complex variables and
algebraic geometry.


title:
Mean-field approximation for a Bose-Hubbard dimer with complex
  interaction strength

abstract:
  In the limit of large particle numbers and low densities systems of cold
atoms can be effectively described as macroscopic single particle systems in a
mean-field approximation. In the case of a Bose-Hubbard system, modelling
bosons on a discrete lattice with on-site interactions, this yields a discrete
nonlinear Schr\"odinger equation of Gross-Pitaevskii type. It has been recently
shown that the correspondence between the Gross-Pitaevskii equation and the
Bose-Hubbard system breaks down for complex extensions. In particular, for a
Bose-Hubbard dimer with complex on-site energy the mean-field approximation
yields a generalised complex nonlinear Schr\"odinger equation. Conversely, a
Gross-Pitaevskii equation with complex on-site energies arises as the
mean-field approximation of many-particle Lindblad dynamics rather than a
complex extension of the Bose-Hubbard system. Here we address the question of
how the mean-field description is modified in the presence of a complex-valued
particle interaction term for a Bose-Hubbard dimer. We derive the mean-field
equations of motion leading to nonlinear dissipative Bloch dynamics, related to
a nontrivial complex generalisation of the nonlinear Schr\"odinger equation.
The resulting dynamics are analysed in detail. It is shown that depending on
the parameter values there can be up to six stationary states, and for small
values of the interaction strength there are limit cycles. Furthermore, we show
how a Gross-Pitaevskii equation with a complex interaction term can be derived
as the mean-field approximation of a Bose-Hubbard dimer with an additional
Lindblad term modelling two-particle losses.


title:
Thin films thickness Measurement by the conductivity theory in the
  framework of born approximation

abstract:
  When the thickness of the layer is smaller than the electrons mean free path,
the morphology affects the conductivity directly based on the layer thickness.
This issue provides basis in order to estimate the thickness of the layer by
understanding the morphology and the value of the conductivity. This method is
an inverse approach on thickness estimation and is applied to various samples.
The comparison of the results with other thickness estimations shows good
consistency. The benefits of this approach is that the only parameter that
needs to be measured is the conductivity, which is quite trivial. Despite the
simplicity of this approach, its results would prove adequate to study both the
material properties and the morphology of the layer. In addition, the
possibility of repeating the measurements on thickness for AC currents with
various frequencies enables averaging the measurements in order to obtain the
most precise results.


title:
Atomistic simulation of the electronic states of adatoms in monolayer
  MoS2

abstract:
  Using an ab initio density functional theory (DFT) based electronic structure
method, we study the effects of adatoms on the electronic properties of
monolayer transition metal dichalcogenide (TMD) Molybdenum-disulfide (MoS2). We
consider the 1st (Li, Na, K) and 7th (F, Cl, Br) column atoms and metals (Sc,
Ti, Ta, Mo, Pd, Pt, Ag, Au). Three high symmetry sites for the adatom on the
surface of monolayer MoS2 are examined as starting points to search for the
most energetically stable configuration for each adatom-monolayer MoS2 system,
as well as the type of associated bonding. For the most stable adatom
positions, we characterize the emergence of adatom-induced electronic states
including any dopant states.


title: The Hierarchical Origins of Observed Galaxy Morphology

abstract:
  Galaxies grow primarily via accretion-driven star formation in discs and
merger-driven growth of bulges. These processes are implicit in semi-analytical
models of galaxy formation, with bulge growth in particular relating directly
to the hierarchical build-up of halos and their galaxies. In this paper, we
consider several implementations of two semi-analytical models. Focusing on
implementations in which bulges are formed during mergers only, we examine the
fractions of elliptical galaxies and both passive and star-forming disk
galaxies as functions of stellar and halo mass, for central and satellite
systems. This is compared to an observational cross-matched SDSS+RC3 z ~ 0
sample of galaxies with accurate visual morphological classifications and
M_{stellar} > 10^10.5 M_{sol}. The models qualitatively reproduce the observed
increase of elliptical fraction with stellar mass, and with halo mass for
central galaxies, supporting the idea that observed ellipticals form during
major mergers. However, the overall elliptical fraction produced by the models
is much too high compared with the z ~ 0 data. Since the "passive" -- i.e.
non-star-forming -- fractions are approximately reproduced, and since the
fraction which are star-forming disc galaxies is also reproduced, the problem
is that the models overproduce ellipticals at the expense of passive S0 and
spiral galaxies. Bulge-growth implementations (tuned to reproduce simulations)
which allow the survival of residual discs in major mergers still destroy too
much of the disc. Increasing the lifetime of satellites, or allowing
significant disc regrowth around merger remnants, merely increases the fraction
of star-forming disc galaxies. Instead, it seems necessary to reduce the mass
ratios of merging galaxies, so that most mergers produce modest bulge growth in
disc-galaxy remnants instead of ellipticals. [Abridged]


title: On Poincar\'e extensions of rational maps

abstract:
  There is a classical extension, of M\"obius automorphisms of the Riemann
sphere into isometries of the hyperbolic space $\mathbb{H}^3$, which is called
the Poincar\'e extension. In this paper, we construct extensions of rational
maps on the Riemann sphere over endomorphisms of $\mathbb{H}^3$ exploiting the
fact that any holomorphic covering between Riemann surfaces is M\"obius for a
suitable choice of coordinates.
  We show that these extensions define conformally natural homomorphisms on
suitable subsemigroups of the semigroup of Blaschke maps. We extend the complex
multiplication to a product in $\mathbb{H}^3$ that allows to construct a visual
extension of any given rational map.


title: Liquid soap film generates electricity

abstract:
  We have observed that a rotating liquid soap film generates electricity when
placed between two non-contact electrodes with a sufficiently large potential
difference. In our experiments suspended liquid film (water + soap film) is
formed on the surface of a circular frame, which is forced to rotate in the
$x-y$ horizontal plane by a motor. This system is located at the center of two
capacitor-like vertical plates to apply an external electric voltage difference
in the $x-$direction. The produced electric current is collected from the
liquid film using two conducting electrodes that are separated in the
$y-$direction. We previously reported that a liquid film in an external
electric field rotates when an electric current passes through it, naming it
the liquid film motor (LFM). In this paper we report a novel technique, in
which a similar device can be used as an electric generator, converting the
rotating mechanical energy to electrical energy. The liquid film electric
generator (LFEG) is in stark contrast to the LFM, both of which could be
designed similarly in very small scales like micro scales with different
applications. Although the device is comparable to commercial electric motors
or electric generators, there is a significant difference in their working
principles. Usually in an electric motor or generator the magnetic field causes
the driving force, while in a LFM or LFEG the Coulomb force is the driving
force. This fact is also interesting from the Bio-science point of view and
brings a similarity to bio motors. Here we have investigated the electrical
characteristics of such a generator for the first time experimentally and
modelled the phenomenon with electroconvection governing equations. A numerical
simulation is performed using the local approximation for the charge-potential
relation and results are in qualitative agreement with experiments.


title: Three- and Four-point correlators of excited bosonic twist fields

abstract:
  We compute three- and four-point correlation functions containing excited
bosonic twist fields. Our results can be used to determine properties, such as
lifetimes and production rates, of massive string excitations localised at
D-brane intersections, which could be signatures of a low string scale even if
the usual string resonances are inaccessible to the LHC.


title:
A Case Study in Coordination Programming: Performance Evaluation of
  S-Net vs Intel's Concurrent Collections

abstract:
  We present a programming methodology and runtime performance case study
comparing the declarative data flow coordination language S-Net with Intel's
Concurrent Collections (CnC). As a coordination language S-Net achieves a
near-complete separation of concerns between sequential software components
implemented in a separate algorithmic language and their parallel orchestration
in an asynchronous data flow streaming network. We investigate the merits of
S-Net and CnC with the help of a relevant and non-trivial linear algebra
problem: tiled Cholesky decomposition. We describe two alternative S-Net
implementations of tiled Cholesky factorization and compare them with two CnC
implementations, one with explicit performance tuning and one without, that
have previously been used to illustrate Intel CnC. Our experiments on a 48-core
machine demonstrate that S-Net manages to outperform CnC on this problem.


title: On conjugacy classes in a reductive group

abstract:
  Let G be a connected reductive group over an algebraically closed field. We
define a decomposition of G into finitely many strata such that each stratum is
a union of conjugacy classes of fixed dimension; the strata are indexed by a
set defined in terms of the Weyl group which is independent of the
characteristic. In the case where $G$ is replaced by the corresponding loop
group we define an analogous decomposition of the set of regular semisimple
compact elements into countably many strata.


title:
Structural and Functional Discovery in Dynamic Networks with
  Non-negative Matrix Factorization

abstract:
  Time series of graphs are increasingly prevalent in modern data and pose
unique challenges to visual exploration and pattern extraction. This paper
describes the development and application of matrix factorizations for
exploration and time-varying community detection in time-evolving graph
sequences. The matrix factorization model allows the user to home in on and
display interesting, underlying structure and its evolution over time. The
methods are scalable to weighted networks with a large number of time points or
nodes, and can accommodate sudden changes to graph topology. Our techniques are
demonstrated with several dynamic graph series from both synthetic and real
world data, including citation and trade networks. These examples illustrate
how users can steer the techniques and combine them with existing methods to
discover and display meaningful patterns in sizable graphs over many time
points.


title:
Multivalued Backward Stochastic Differential Equations with Time Delayed
  Generators

abstract:
  Our aim is to study the following new type of multivalued backward stochastic
differential equation: \[ \left\{\begin{array} [c]{r}-dY\left(t\right)
+\partial\varphi\left(Y\left(t\right)\right) dt\ni
F\left(t,Y\left(t\right),Z\left(t\right),Y_{t},Z_{t}\right) dt+Z\left(t\right)
dW\left(t\right),\;0\leq t\leq T,\medskip\\ \multicolumn{1}{l}{Y\left(T\right)
=\xi,}\end{array} \right. \] where $\partial\varphi$ is the subdifferential of
a convex function and
$\left(Y_{t},Z_{t}\right):=(Y(t+\theta),Z(t+\theta))_{\theta\in\lbrack-T,0]}$
represent the past values of the solution over the interval $\left[ 0,t\right]
$. Our results are based on the existence theorem from Delong & Imkeller, Ann.
Appl. Probab., 2010, concerning backward stochastic differential equations with
time delayed generators.


title:
Manipulating chiral transmission by gate geometry: switching in graphene
  with transmission gaps

abstract:
  We explore the chiral transmission of electrons across graphene
heterojunctions for electronic switching using gate geometry alone. A sequence
of gates is used to collimate and orthogonalize the chiral transmission lobes
across multiple junctions, resulting in negligible overall current. The
resistance of the device is enhanced by several orders of magnitude by biasing
the gates into the bipolar $npn$ doping regime, as the ON state in the near
homogeneous $nn^-n$ regime remains highly conductive. The mobility is preserved
because the switching involves a transmission gap instead of a structural
band-gap that would reduce the number of available channels of conduction.
Under certain conditions this transmission gap is highly gate tunable, allowing
a subthermal turn-on that beats the Landauer bound on switching energy limiting
present day digital electronics.


title: Growth polynomials for additive quadruples and $(h,k)$-tuples

abstract:
  Consider the interval of integers $I_{m,n} = \{m, m+1, m+2,\ldots, m+n-1 \}$.
For fixed integers $h,k,m$, and $c$, let $\Phi_{h,k,m}^{(c)}(n)$ denote the
number of solutions of the equation $(a_1+\cdots + a_h)- (a_{h+1} + \cdots +
a_{h+k})=c$ with $a_i \in I_{m,n}$ for all $i=1,\ldots, h+k$. This is a
polynomial in $n$ for all sufficiently large $n$, and the growth polynomial is
constructed explicitly.


title: Search for Dark Matter in the sky with the Fermi Large Area Telescope

abstract:
  Can we learn about New Physics with astronomical and astro-particle data?
Since its launch in 2008, the Large Area Telescope, onboard of the Fermi
Gamma-ray Space Telescope, has detected the largest amount of gamma rays in the
20 MeV - 300 GeV energy range and electrons + positrons in the 7 GeV- 1 TeV
range. These impressive statistics allow one to perform a very sensitive
indirect experimental search for dark matter. We will present the latest
results on these searches and the comparison with LHC searches.


title: On weak uniqueness for some degenerate SDEs by global $L^p$ estimates

abstract:
  We prove uniqueness in law for possibly degenerate SDEs having a linear part
in the drift term. Diffusion coefficients corresponding to non-degenerate
directions of the noise are assumed to be continuous. When the diffusion part
is constant we recover the classical degenerate Ornstein-Uhlenbeck process
which only has to satisfy the H\"ormander hypoellipticity condition. In the
proof we use global $L^p$-estimates for hypoelliptic Ornstein-Uhlenbeck
operators recently proved in Bramanti-Cupini-Lanconelli-Priola (Math. Z. 266
(2010)) and adapt the localization procedure introduced by Stroock and
Varadhan. Appendix contains a quite general localization principle for
martingale problems.


title: Nonlinear Traces

abstract:
  We combine the theory of traces in homotopical algebra with sheaf theory in
derived algebraic geometry to deduce general fixed point and character
formulas. The formalism of dimension (or Hochschild homology) of a dualizable
object in the context of higher algebra provides a unifying framework for
classical notions such as Euler characteristics, Chern characters, and
characters of group representations. Moreover, the simple functoriality
properties of dimensions clarify celebrated identities and extend them to new
contexts.
  We observe that it is advantageous to calculate dimensions, traces and their
functoriality directly in the nonlinear geometric setting of correspondence
categories, where they are directly identified with (derived versions of) loop
spaces, fixed point loci and loop maps, respectively. This results in universal
nonlinear versions of Grothendieck-Riemann-Roch theorems, Atiyah-Bott-Lefschetz
trace formulas, and Frobenius-Weyl character formulas. On the one hand, we can
then linearize by applying sheaf theories, such as the theories of coherent
sheaves and D-modules, developed by Gaitsgory and Rozenblyum, as functors out
of correspondence categories (in the spirit of topological field theory). This
recovers the familiar classical identities, in families and without any
smoothness or transversality assumptions. On the other hand, the formalism also
applies to higher categorical settings not captured within a linear framework,
such as characters of group actions on categories.


title:
Main-belt comets in the Palomar Transient Factory survey: I. The search
  for extendedness

abstract:
  Cometary activity in main-belt asteroids probes the ice content of these
objects and provides clues to the history of volatiles in the inner solar
system. We search the Palomar Transient Factory (PTF) survey to derive upper
limits on the population size of active main-belt comets (MBCs). From data
collected March 2009 through July 2012, we extracted 2 million observations of
220 thousand known main-belt objects (40% of the known population, down to 1-km
diameter) and discovered 626 new objects in multi-night linked detections. We
formally quantify the extendedness of a small-body observation, account for
systematic variation in this metric (e.g., due to on-sky motion) and evaluate
this method's robustness in identifying cometary activity using observations of
115 comets, including two known candidate MBCs and six newly-discovered
non-main-belt comets (two of which were originally designated as asteroids by
other surveys). We demonstrate a 66% detection efficiency with respect to the
extendedness distribution of the 115 sampled comets, and a 100% detection
efficiency with respect to extendedness levels greater than or equal to those
we observed in the known candidate MBCs P/2010 R2 (La Sagra) and P/2006 VW139.
Using a log-constant prior, we infer 95% confidence upper limits of 33 and 22
active MBCs (per million main-belt asteroids down to 1-km diameter), for
detection efficiencies of 66% and 100%, respectively. In a follow-up to this
morphological search, we will perform a photometric (disk-integrated
brightening) search for MBCs.


title: Secondary Traces

abstract:
  We study an invariant, the secondary trace, attached to two commuting
endomorphisms of a 2-dualizable object in a symmetric monoidal higher category.
We establish a secondary trace formula which encodes the natural symmetries of
this invariant, identifying different realizations as an iterated trace. The
proof consists of elementary Morse-theoretic arguments (with many accompanying
pictures included) and may be seen as a concrete realization of the cobordism
hypothesis with singularities on a marked 2-torus. From this perspective, our
main result identifies the secondary trace with two alternative presentations
coming from the standard generators S and T of the mapping class group SL_2(Z).
  We include two immediate consequences of the established invariance. The
first is a modular invariance property for the 2-class function on a group
arising as the 2-character of a categorical representation. The second is a
generalization (for coherent sheaves or D-modules) of the Atiyah-Bott-Lefschetz
formula conjectured by Frenkel-Ng\^o in the case of a self-map of a smooth and
proper stack over a general base.


title:
Extreme intensity pulses in a semiconductor laser with a short external
  cavity

abstract:
  We present a numerical study of the pulses displayed by a semiconductor laser
with optical feedback in the short cavity regime, such that the external cavity
round trip time is smaller than the laser relaxation oscillation period. For
certain parameters there are occasional pulses, which are high enough to be
considered extreme events. We characterize the bifurcation scenario that gives
rise to such extreme pulses and study the influence of noise. We demonstrate
intermittency when the extreme pulses appear and hysteresis when the attractor
that sustains these pulses is destroyed. We also show that this scenario is
robust under the inclusion of noise.


title: Testing the well-posedness of characteristic evolution of scalar waves

abstract:
  Recent results have revealed a critical way in which lower order terms affect
the well-posedness of the characteristic initial value problem for the scalar
wave equation. The proper choice of such terms can make the Cauchy problem for
scalar waves well posed even on a background spacetime with closed lightlike
curves. These results provide new guidance for developing stable characteristic
evolution algorithms. In this regard, we present here the finite difference
version of these recent results and implement them in a stable evolution code.
We describe test results which validate the code and exhibit some of the
interesting features due to the lower order terms.


title: Transport coefficients from the Nambu-Jona-Lasinio model for $SU(3)_f$

abstract:
  We calculate the shear $\eta(T)$ and bulk viscosities $\zeta(T)$ as well as
the electric conductivity $\sigma_e(T)$ and heat conductivity $\kappa(T)$
within the Nambu-Jona-Lasinio model for 3 flavors as a function of temperature
as well as the entropy density $s(T)$, pressure $P(T)$ and speed of sound
$c_s^2(T)$. We compare the results with other models such as the
Polyakov-Nambu-Jona-Lasinio (PNJL) model and the dynamical quasiparticle model
(DQPM) and confront these results with lattice QCD data whenever available. We
find the NJL model to have a limited predictive power for the thermodynamic
variables and various transport coefficients above the critical temperature
whereas the PNJL model and DQPM show acceptable results for the quantities of
interest.


title: Lensless Imaging by Compressive Sensing

abstract:
  In this paper, we propose a lensless compressive imaging architecture. The
architecture consists of two components, an aperture assembly and a sensor. No
lens is used. The aperture assembly consists of a two dimensional array of
aperture elements. The transmittance of each aperture element is independently
controllable. The sensor is a single detection element. A compressive sensing
matrix is implemented by adjusting the transmittance of the individual aperture
elements according to the values of the sensing matrix. The proposed
architecture is simple and reliable because no lens is used. The architecture
can be used for capturing images of visible and other spectra such as infrared,
or millimeter waves, in surveillance applications for detecting anomalies or
extracting features such as speed of moving objects. Multiple sensors may be
used with a single aperture assembly to capture multi-view images
simultaneously. A prototype was built by using a LCD panel and a photoelectric
sensor for capturing images of visible spectrum.


title:
Average Consensus on Arbitrary Strongly Connected Digraphs with
  Time-Varying Topologies

abstract:
  We have recently proposed a "surplus-based" algorithm which solves the
multi-agent average consensus problem on general strongly connected and static
digraphs. The essence of that algorithm is to employ an additional variable to
keep track of the state changes of each agent, thereby achieving averaging even
though the state sum is not preserved. In this note, we extend this approach to
the more interesting and challenging case of time-varying topologies: An
extended surplus-based averaging algorithm is designed, under which a necessary
and sufficient graphical condition is derived that guarantees state averaging.
The derived condition requires only that the digraphs be arbitrary strongly
connected in a \emph{joint} sense, and does not impose "balanced" or
"symmetric" properties on the network topology, which is therefore more general
than those previously reported in the literature.


title: Antiproton Limits on Decaying Gravitino Dark Matter

abstract:
  We derive 95% CL lower limits on the lifetime of decaying dark matter in the
channels $Z\nu$, $W\ell$ and $h\nu$ using measurements of the cosmic-ray
antiproton flux by the PAMELA experiment. Performing a scan over the allowed
range of cosmic-ray propagation parameters we find lifetime limits in the range
of $8 \times 10^{28}$s to $5 \times 10^{25}$s for dark matter masses from
roughly 100 GeV to 10 TeV. We apply these limits to the well-motivated case of
gravitino dark matter in scenarios with bilinear violation of R-parity and find
a similar range of lifetime limits for the same range of gravitino masses.
Converting the lifetime limits to constraints on the size of the R-parity
violating coupling we find upper limits in the range of $10^{-8}$ to $8 \times
10^{-13}$.


title: Defining relations and flip Dynkin superdiagrams

abstract:
  The motivation comes from boson fermion correspondence. This article shows
for each fermionic root there is correspondence a bosonic root, as a result we
get for each Dynkin diagram of Lie Superalgebra a corresponding flip Dynkin
Superdiagram. This article construct all the filp Dynkin Superdiagrams of Lie
superalgebras(LS). This can create non conjugate classes Borel subalgebra
(subsuperalgebras) or non isomorphic Dynkin diagrams of LS using \in\delta
sequences. We have got the defining relations for the both the Dynkin diagrams
and flip Dynkin diagrams.


title: Collaborative ontology sharing and editing

abstract:
  This article first lists reasons why - in the long term or when creating a
new knowledge base (KB) for general knowledge sharing purposes -
collaboratively building a well-organized KB does/can provide more
possibilities, with on the whole no more costs, than the mainstream approach
where knowledge creation and re-use involves searching, merging and creating
(semi-)independent (relatively small) ontologies or semi-formal documents. The
article lists elements required to achieve this and describes the main one: a
KB editing protocol that keeps the KB free of automatically/manually detected
inconsistencies while not forcing them to discuss or agree on terminology and
beliefs nor requiring a selection committee.


title:
There is no finite variable axiomatization for various diagonal free
  algebras

abstract:
  We show, using a ranbow construction for cylindric algebras, that for any
class K between diagonal free cylindric algebras and polyadic equality algebras
of finite dimension > 2, there is no finite variable universal axiomatization
for the class of representable algebras. This solves an old open problem in
algebraic logic, formulated by Sain and Thompson back in 1990.


title:
Studying solutions to Diophantine equations using the table of $N$th
  digital roots of integers

abstract:
  In this note we recall the definition of the digital root, and apply the
notion of the digital root to searching solutions of Diophantine equations. A
table of arithmetic operations with digital roots is given. This method is
incapable of obtaining complete solutions of equations, but it is frequently
useful in determining whether this equation is solvable in integers or not. A
minor extension of Fermat's little theorem is put forward.


title:
A semi-classical versus quantum description of the ground state of
  three-level atoms interacting with a one-mode electromagnetic field

abstract:
  We consider $N_a$ three-level atoms (or systems) interacting with a one-mode
electromagnetic field in the dipolar and rotating wave approximations. The
order of the quantum phase transitions is determined explicitly for each of the
configurations $\Xi$, $\Lambda$ and $V$, with and without detuning. The
semi-classical and exact quantum calculations for both the expectation values
of the total number of excitations $\cal{M}=\langle \bm{M} \rangle$ and photon
number $n=\langle \bm{n} \rangle$ have an excellent correspondence as functions
of the control parameters. We prove that the ground state of the collective
regime obeys sub-Poissonian statistics for the ${\cal M}$ and $n$ distribution
functions. Therefore, their corresponding fluctuations are not well described
by the semiclassical approximation. We show that this can be corrected by
projecting the variational state to a definite value of ${\cal M}$.


title: Splints of root systems on Lie Superalgebras

abstract:
  This paper classifies the splints of the root system of classical Lie
superalgebras as a superalgebraic conversion of the splints of classical root
systems. It can be used to derive branching rules, which have potential
physical application in theoretical physics.


title: Vector Fields in Holographic Cosmology

abstract:
  We extend the holographic formulation of the semiclassical no-boundary wave
function (NBWF) to models with Maxwell vector fields. It is shown that the
familiar saddle points of the NBWF have a representation in which a regular,
Euclidean asymptotic AdS geometry smoothly joins onto a Lorentzian
asymptotically de Sitter universe through a complex transition region. The tree
level probabilities of Lorentzian histories are fully specified by the action
of the AdS region of the saddle points. The scalar and vector matter profiles
in this region are complex from an AdS viewpoint, with universal asymptotic
phases. The dual description of the semiclassical NBWF thus involves complex
deformations of Euclidean CFTs.


title: Holographic R\'enyi Entropies at Finite Coupling

abstract:
  We compute R\'enyi entropies for a spherical entangling surface in
four-dimensional N=4 super-Yang-Mills at strong coupling using the AdS/CFT
correspondence. Incorporating the effects of the leading \alpha' corrections to
the low energy effective action of type IIB string theory, we calculate the
leading corrections in inverse powers of the 't Hooft coupling (and the number
of colours). The results are compared with known weak coupling calculations.
Setting the order of the R\'enyi entropy q to one, it reduces to the
entanglement entropy and the strong and weak coupling results match without any
corrections, as expected. In the limit of q going to 0, the relation between
the strong and weak coupling entropies is connected to the known corrections
for the thermal free energy in flat space. We also compute the correction to
the scaling dimension of twist operators.


title:
Using Monoidal Categories in the Transformational Study of Musical
  Time-Spans and Rhythms

abstract:
  Transformational musical theory has so far mainly focused on the study of
groups acting on musical chords, one of the most famous example being the
action of the dihedral group D24 on the set of major and minor chords.
Comparatively less work has been devoted to the study of transformations of
time-spans and rhythms. D. Lewin was the first to study group actions on
time-spans by using a subgroup of the affine group in one dimension. In our
previous work, the work of Lewin has been included in the more general
framework of group extensions, and generalizations to time-spans on multiple
timelines have been proposed. The goal of this paper is to show that such
generalizations have a categorical background in free monoidal categories
generated by a group-as-category. In particular, symmetric monoidal categories
allow to deal with the possible interexchanges between timelines. We also show
that more general time-spans can be considered, in which single time-spans are
encapsulated in a "bracket" of time-spans, which allows for the description of
complex rhythms.


title: The laminations of a crystal near an anti-continuum limit

abstract:
  The anti-continuum limit of a monotone variational recurrence relation
consists of a lattice of uncoupled particles in a periodic background. This
limit supports many trivial equilibrium states that persist as solutions of the
model with small coupling. We investigate when a persisting solution generates
a so-called lamination and prove that near the anti-continuum limit the
collection of laminations of solutions is homeomorphic to the (N-1)-dimensional
simplex, with N the number of distinct local minima of the background
potential. This generalizes a result by Baesens and MacKay on twist maps near
an anti-integrable limit.


title: The Dynamics of Genetic Draft in Rapidly Adapting Populations

abstract:
  The accumulation of beneficial mutations on many competing genetic
backgrounds in rapidly adapting populations has a striking impact on
evolutionary dynamics. This effect, known as clonal interference, causes
erratic fluctuations in the frequencies of observed mutations, randomizes the
fixation times of successful mutations, and leaves distinct signatures on
patterns of genetic variation. Here, we show how this form of `genetic draft'
affects the forward-time dynamics of site frequencies in rapidly adapting
asexual populations. We calculate the probability that mutations at individual
sites shift in frequency over a characteristic timescale, extending Gillespie's
original model of draft to the case where many strongly selected beneficial
mutations segregate simultaneously. We then derive the sojourn time of mutant
alleles, the expected fixation time of successful mutants, and the site
frequency spectrum of beneficial and neutral mutations. We show how this form
of draft affects inferences in the McDonald-Kreitman test, and how it relates
to recent observations that some aspects of genetic diversity are described by
the Bolthausen-Sznitman coalescent in the limit of very rapid adaptation.
Finally, we describe how our method can be extended to model evolution on
fitness landscapes that include some forms of epistasis, such as landscapes
that are partitioned into two or more incompatible evolutionary trajectories.


title: Resonant Compton scattering of electromagnetic waves in a quantum plasma

abstract:
  We consider the resonant scattering of coherent electromagnetic waves by a
Raman-like process in the gamma ray range off electrostatic modes in a quantum
plasma using a collective Klein-Gordon-Maxwell model. The growth rates for the
most unstable modes are calculated theoretically, and the results are found to
be more efficient than incoherent Compton scattering off individual electrons
above a critical amplitude of the electromagnetic wave. The model does not
predict Raman scattering off pair modes that exist in the Klein-Gordon-Maxwell
model. The results are relevant for coherent gamma rays created in forthcoming
laboratory experiments or in astrophysical objects.


title:
For a Semantic Web based Peer-reviewing and Publication of Research
  Results

abstract:
  This article shows why the diffusion and peer-reviewing of research results
would be more efficient, precise and relevant if all or at least some parts of
the descriptions and peer-reviews of research results took the form of a
fine-grained semantic network, within articles or knowledge bases, as part of
the Semantic Web. This article also shows some ways this can be done and hence
how research journal/proceeding publishers could allow this. So far, the World
Wide Web Consortium (W3C) has not proposed simple notations and cooperation
protocols - similar to those illustrated or referred to in this article - but
it now seems likely that Wikipedia/Wikidata, Google or the W3C will propose
them sooner or later. Then, research journal/proceeding publishers and
researchers may or may not quickly use this approach.


title:
Gravitational wave asteroseismology of fast rotating neutron stars with
  realistic equations of state

abstract:
  In the present paper we study the oscillations of fast rotating neutron stars
with realistic equations of state (EoS) within the Cowling approximation. We
derive improved empirical relations for gravitational wave asteroseismology
with f-modes and for the first time we consider not only quadrupolar
oscillations but also modes with higher spherical order (l=|m|=3,4). After
performing a systematic comparison with polytropic EoS, it is shown that the
empirical relations found in this case approximately also hold for realistic
EoS. Even more, we show that these relations will not change significantly even
if the Cowling approximation is dropped and the full general relativistic case
is considered, although the normalization used here(frequencies and damping
times in the nonrotating limit) could differ considerably. We also address the
inverse problem, i.e. we investigate in detail what kind of observational data
is required in order to determine characteristical neutron star parameters. It
is shown that masses, radii and rotation rates can be estimated quite
accurately using the derived asteroseismology relations. We also compute the
instability window for certain models, i.e. the limiting curve in a
T-\Omega-plane where the secular Chandrasekhar-Friedman-Schutz(CFS) instability
overcomes dissipative effects, and show that some of the modern realistic EoS
will lead to a larger instability window compared to all of the polytropic ones
presented so far in the literature. Additionally, we calculate the r-mode
instability window and compare it with the f-mode-case. The overall results for
the instability window suggest that it is vital to take into account
oscillations with l=3,4 when considering gravitational wave asteroseismology
using the f-mode in rapidly rotating neutron stars, as these modes can become
CFS unstable for a much larger range of parameters than pure quadrupolar
oscillations.


title:
Weakly convex biharmonic hypersurfaces in nonpositive curvature space
  forms are minimal

abstract:
  A submanifold $M^m$ of a Euclidean space $R^{m+p}$ is said to have harmonic
mean curvature vector field if $\Delta \vec{H}=0$, where $\vec{H}$ is the mean
curvature vector field of $M\hookrightarrow R^{m+p}$ and $\Delta$ is the rough
Laplacian on $M$. There is a conjecture named after Bangyen Chen which states
that submanifolds of Euclidean spaces with harmonic mean curvature vector
fields are minimal. In this paper we prove that weakly convex hypersurfaces
(i.e. hypersurfaces whose principle curvatures are nonnegative) with harmonic
mean curvature vector fields in Euclidean spaces are minimal. Furthermore we
prove that weakly convex biharmonic hypersurfaces in nonpositive curved space
forms are minimal.


title: Z-pole observables in an effective theory

abstract:
  There are two Z-peak observables related to the pair production of bottom
quarks that show a deviation of about 2.5\sigma\ each from Standard Model
expectations. While the discrepancy in the forward-backward asymmetry is a
long-standing one, the tension for the second observable, namely the ratio of
the partial width for a Z decaying to a pair of bottom quarks to the total
hadronic decay width of the Z, has recently gone up due to a full two-loop
evaluation of the Standard Model contributions. We show how both these
discrepancies may be explained in the framework of new physics that couples
only to the third generation of quarks. In the paradigm of effective operators,
the Wilson coefficients of some of the possible operators are already very
tightly constrained by flavour physics data. However, there still remain
certain operators, particularly those involving right-chiral quark fields,
which can successfully explain the anomalies. We also show how the footprints
of such operators may be observed at the upgraded LHC.


title: Organizing Linked Data Quality Related Methods

abstract:
  This article presents the top-level of an ontology categorizing and
generalizing best practices and quality criteria or measures for Linked Data.
It permits to compare these techniques and have a synthetic organized view of
what can or should be done for knowledge sharing purposes. This ontology is
part of a general knowledge base that can be accessed and complemented by any
Web user. Thus, it can be seen as a cooperatively built library for the above
cited elements. Since they permit to evaluate information objects and create
better ones, these elements also permit knowledge-based tools and techniques -
as well as knowledge providers - to be evaluated and categorized based on their
input/output information objects. One top-level distinction permitting to
organize this ontology is the one between content, medium and containers of
descriptions. Various structural, ontological, syntactical and lexical
distinctions are then used.


title:
Origin of giant spin-lattice coupling and the suppression of
  ferroelectricity in EuTiO3 from first principles

abstract:
  We elucidate the microscopic mechanism that causes a suppression of
ferroelectricity and an enhancement of octahedral rotations in EuTiO3 from
first principles. We find that the hybridization of the rare-earth Eu 4f states
with the B-site Ti cation drives the system away from ferroelectricity. We also
show that the magnetic order dependence of this hybridization is the dominant
source of spin-phonon coupling in this material. Our results underline the
importance of rare-earth f electrons on the lattice dynamics and stability of
these transition metal oxides.


title: Interaction quenches in the 1D Bose gas

abstract:
  The non-equilibrium dynamics of integrable systems are special: there is
substantial evidence that after a quantum quench they do not thermalize but
their asymptotic steady state can be described by a Generalized Gibbs Ensemble
(GGE). Most of the studies on the GGE so far have focused on models that can be
mapped to quadratic systems while analytic treatment in non-quadratic systems
remained elusive. We obtain results on interaction quenches in a non-quadratic
continuum system, the 1D Bose gas described by the integrable Lieb-Liniger
model. We compute local correlators for a non-interacting initial state and
arbitrary final interactions as well as two-point functions for quenches to the
Tonks-Girardeau regime. We show that in the long time limit integrability leads
to significant deviations from the predictions of the grand canonical ensemble.


title: Theory of defects in Abelian topological states

abstract:
  The structure of extrinsic defects in topologically ordered states of matter
is host to a rich set of universal physics. Extrinsic defects in 2+1
dimensional topological states include line-like defects, such as boundaries
between topologically distinct states, and point-like defects, such as
junctions between different line defects. Gapped boundaries in particular can
themselves be \it topologically \rm distinct, and the junctions between them
can localize topologically protected zero modes, giving rise to topological
ground state degeneracies and projective non-Abelian statistics. In this paper,
we develop a general theory of point defects and gapped line defects in 2+1
dimensional Abelian topological states. We derive a classification of
topologically distinct gapped boundaries in terms of certain maximal subgroups
of quasiparticles with mutually bosonic statistics, called Lagrangian
subgroups. The junctions between different gapped boundaries provide a general
classification of point defects in topological states, including as a special
case the twist defects considered in previous works. We derive a general
formula for the quantum dimension of these point defects, a general
understanding of their localized "parafermion" zero modes, and we define a
notion of projective non-Abelian statistics for them. The critical phenomena
between topologically distinct gapped boundaries can be understood in terms of
a general class of quantum spin chains or, equivalently, "generalized
parafermion" chains. This provides a way of realizing exotic 1+1D generalized
parafermion conformal field theories in condensed matter systems.