title: Energy, Latency, and Reliability Tradeoffs in Coding Circuits

abstract:
  It is shown that fully-parallel encoding and decoding schemes with asymptotic
block error probability that scales as $O\left(f\left(n\right)\right)$ have
Thompson energy that scales as $\Omega\left(\sqrt{\ln
f\left(n\right)}n\right)$. As well, it is shown that the number of clock cycles
(denoted $T\left(n\right)$) required for any encoding or decoding scheme that
reaches this bound must scale as $T\left(n\right)\ge\sqrt{\ln
f\left(n\right)}$. Similar scaling results are extended to serialized
computation.
  The Grover information-friction energy model is generalized to three
dimensions and the optimal energy of encoding or decoding schemes with
probability of block error $P_\mathrm{e}$ is shown to be at least
$\Omega\left(n\left(\ln
P_{\mathrm{e}}\left(n\right)\right)^{\frac{1}{3}}\right)$.


title:
Radiative rates for E1, E2, M1, and M2 transitions in S-like to F-like
  tungsten ions (W LIX to W LXVI)

abstract:
  Calculations of energy levels, radiative rates and lifetimes are reported for
eight ions of tungsten, i.e. S-like (W LIX) to F-like (W LXVI). A large number
of levels has been considered for each ion and extensive configuration
interaction has been included among a range of configurations. For the
calculations, the general-purpose relativistic atomic structure package (GRASP)
has been adopted, and radiative rates (as well as oscillator strengths and line
strengths) are listed for all E1, E2, M1, and M2 transitions of the ions.
Comparisons have been made with earlier available experimental and theoretical
energies, although these are limited to only a few levels for most ions.
Therefore for additional accuracy assessments, particularly for energy levels,
analogous calculations have been performed with the flexible atomic code (FAC).


title: Spin dynamics in the high-field phases of volborthite

abstract:
  We report single-crystal 51V NMR studies on volborthite Cu3V2O7(OH)2 2H2O,
which is regarded as a quasi-two-dimensional frustrated magnet with competing
ferromagnetic and antiferromagnetic interactions. In the 1/3 magnetization
plateau above 28 T, the nuclear spin-lattice relaxation rate 1/T1 indicates an
excitation gap with a large effective g factor in the range of 4.6-5.9,
pointing to magnon bound states. Below 26 T where the gap has closed, the NMR
spectra indicate small internal fields with a Gaussian-like distribution,
whereas 1/T1 shows a power-law-like temperature dependence in the paramagnetic
state, which resembles a slowing down of spin fluctuations associated with
magnetic order. We discuss the possibility of an exotic spin state caused by
the condensation of magnon bound states below the magnetization plateau.


title:
Study of collective flows of protons and $\pi^{-}$ -mesons in p(C, Ta)
  and He(Li, C) collisions at momenta of 4.2, 4.5 and 10 AGeV/c

abstract:
  Collective flows of protons and $\pi^{-}$-mesons are studied at the momenta
of 4.2, 4.5 and 10 AGeV/c for p(C, Ta) and He(Li, C) interactions. The data
were obtained from the streamer chamber (SKM-200-GIBS) and from the Propane
Bubble Chamber (PBC-500) systems utilized at JINR. The method of Danielewicz
and Odyniec has been employed in determining the directed transverse flow of
particles. The values of the transverse flow parameter and the strength of the
anisotropic emission were defined for each interacting nuclear pair. It is
found that the directed flows of protons and pions decrease with increase of
the energy and the mass numbers of colliding nucleus pairs. The $\pi^{-}$-meson
and proton flows exhibit opposite directions in all studied interactions, and
the flows of protons are directed in the reaction plane. The Ultra-relativistic
Quantum Molecular Dynamical Model (UrQMD), enlarged by the Statistical
Multi-fragmentation Model (SMM), satisfactorily describes obtained experimental
results.


title:
Shifting nodal-plane suppressions in high-order harmonic spectra from
  diatomic molecules in orthogonally polarized driving fields

abstract:
  We analyze the imprint of nodal planes in high-order harmonic spectra from
aligned diatomic molecules in intense laser fields whose components exhibit
orthogonal polarizations. We show that the typical suppression in the spectra
associated to nodal planes is distorted, and that this distortion can be
employed to map the electron's angle of return to its parent ion. This
investigation is performed semi-analytically at the single-molecule response
and single-active orbital level, using the strong-field approximation and the
steepest descent method. We show that the velocity form of the dipole operator
is superior to the length form in providing information about this distortion.
However, both forms introduce artifacts that are absent in the actual
momentum-space wavefunction. Furthermore, elliptically polarized fields lead to
larger distortions in comparison to two-color orthogonally polarized fields.
These features are investigated in detail for $\mathrm{O}_2$, whose highest
occupied molecular orbital provides two orthogonal nodal planes.


title:
Counting Zeros in Random Walks on the Integers and Analysis of Optimal
  Dual-Pivot Quicksort

abstract:
  We present an average case analysis of two variants of dual-pivot quicksort,
one with a non-algorithmic comparison-optimal partitioning strategy, the other
with a closely related algorithmic strategy. For both we calculate the expected
number of comparisons exactly as well as asymptotically, in particular, we
provide exact expressions for the linear, logarithmic, and constant terms. An
essential step is the analysis of zeros of lattice paths in a certain
probability model. Along the way a combinatorial identity is proven.


title: A Truthful Mechanism with Biparameter Learning for Online Crowdsourcing

abstract:
  We study a problem of allocating divisible jobs, arriving online, to workers
in a crowdsourcing setting which involves learning two parameters of
strategically behaving workers. Each job is split into a certain number of
tasks that are then allocated to workers. Each arriving job has to be completed
within a deadline and each task has to be completed satisfying an upper bound
on probability of failure. The job population is homogeneous while the workers
are heterogeneous in terms of costs, completion times, and times to failure.
The job completion time and time to failure of each worker are stochastic with
fixed but unknown means. The requester is faced with the challenge of learning
two separate parameters of each (strategically behaving) worker simultaneously,
namely, the mean job completion time and the mean time to failure. The time to
failure of a worker depends on the duration of the task handled by the worker.
Assuming non-strategic workers to start with, we solve this biparameter
learning problem by applying the Robust UCB algorithm. Then, we non-trivially
extend this algorithm to the setting where the workers are strategic about
their costs. Our proposed mechanism is dominant strategy incentive compatible
and ex-post individually rational with asymptotically optimal regret
performance.


title: Dynamics in the Szeg\"o class and polynomial asymptotics

abstract:
  We introduce the Szeg\"o class, Sz(E), for an arbitrary Parreau-Widom set E
in R and study the dynamics of its elements under the left shift. When the
direct Cauchy theorem holds on C\E, we show that to each J in Sz(E) there is a
unique element J' in the isospectral torus, T_E, so that the left-shifts of J
are asymptotic to the orbit {J'_m} on T_E. Moreover, we show that the ratio of
the associated orthogonal polynomials has a limit, expressible in terms of Jost
functions, as the degree n tends to infinity. This enables us to describe the
large n behaviour of the orthogonal polynomials for every J in the Szeg\"o
class.


title: On Scaling Rules for Energy of VLSI Polar Encoders and Decoders

abstract:
  It is shown that all polar encoding schemes of rate $R>\frac{1}{2}$ of block
length $N$ implemented according to the Thompson VLSI model must take energy
$E\ge\Omega\left(N^{3/2}\right)$. This lower bound is achievable up to
polylogarithmic factors using a mesh network topology defined by Thompson and
the encoding algorithm defined by Arikan. A general class of circuits that
compute successive cancellation decoding adapted from Arikan's butterfly
network algorithm is defined. It is shown that such decoders implemented on a
rectangle grid for codes of rate $R>2/3$ must take energy
$E\ge\Omega(N^{3/2})$, and this can also be reached up to polylogarithmic
factors using a mesh network. Capacity approaching sequences of energy optimal
polar encoders and decoders, as a function of reciprocal gap to capacity $\chi
= (1-R/C)^{-1}$, have energy that scales as $\Omega\left(\chi^{5.325}\right)\le
E \le O\left(\chi^{7.05}\log^{4}\left(\chi\right)\right)$.


title:
QED radiative corrections and their impact on H -> tau tau searches at
  the LHC

abstract:
  In this paper we show that the excess of the tau tau events with respect to
the Standard Model background predictions, observed by the ATLAS and CMS
collaborations and interpreted as the evidence of the Higgs-boson decay into a
pair of tau-leptons, may be accounted for by properly taking into account QED
radiative corrections in the modelling of the Z/gamma* -> tau tau background.


title:
A CG-type method in Banach spaces with an application to computerized
  tomography

abstract:
  Conjugate Gradient (CG) methods are one of the most effective iterative
methods to solve linear equations in Hilbert spaces. So far, they have been
inherently bound to these spaces since they make use of the inner product
structure. In more general Banach spaces one of the most prominent iterative
solvers are Landweber-type methods that essentially resemble the Steepest
Descent method applied to the normal equation. More advanced are subspace
methods that take up the idea of a Krylov-type search space, wherein an optimal
solution is sought. However, they do not share the conjugacy property with CG
methods. In this article we propose that the Sequential Subspace Optimization
(SESOP) method can be considered as an extension of CG methods to Banach
spaces. We employ metric projections to orthogonalize the current search
direction with respect to the search space from the last iteration. For the
l2-space our method then exactly coincides with the Polak-Ribi\`ere type of the
CG method when applied to the normal equation. We show that such an
orthogonalized search space still leads to weak convergence of the subspace
method. Moreover, numerical experiments on a random matrix toy problem and 2D
computerized tomography on lp-spaces show superior convergence properties over
all p compared to non-orthogonalized search spaces. This especially holds for
lp-spaces with small p. We see that the closer we are to an l2-space, the more
we recover of the conjugacy property that holds in these spaces, i. e., as
expected, the more the convergence behaves independently of the size of the
truncated search space.


title:
Identifying quantum subsystems using Clausius' second law of
  thermodynamics

abstract:
  There are many ways to decompose the Hilbert space H of a composite quantum
system into tensor product subspaces. Different subsystem decompositions
generally imply different interaction Hamiltonians V, and therefore different
expectation values for subsystem observables. This means that thE uniqueness of
physical predictions is not guaranteed, despite the uniqueness of the total
Hamiltonian H and the total Hilbert space. Here we use Clausius' version of the
second law of thermodynamics (CSL) and standard identifications of
thermodynamic quantities to identify possible subsystem decompositions. It is
shown that agreement with the CSL is obtained, whenever the total Hamiltonian
and the subsystem-dependent interaction Hamiltonian commute (i.e. [H,V]=0). Not
imposing this constraint can result in the transfer of heat from a cooler to a
hotter subsystem, in conflict with thermodynamics. We also investigate the
status of the CSL with respect to non- standard definitions of thermodynamic
quantities and quantum subsystems.


title:
Modeling of critical experiments and its impact on integral covariance
  matrices and correlation coefficients

abstract:
  In this manuscript we study the modeling of experimental data and its impact
on the resulting integral experimental covariance and correlation matrices. By
investigating a set of three low enriched and water moderated UO2 fuel rod
arrays we found that modeling the same set of data with different, yet
reasonable assumptions concerning the fuel rod composition and its geometric
properties leads to significantly different covariance matrices or correlation
coefficients. Following a Monte Carlo sampling approach, we show for nine
different modeling assumptions the corresponding correlation coefficients and
sensitivity profiles for each pair of the effective neutron multiplication
factor keff. Within the 95% confidence interval the correlation coefficients
vary from 0 to 1, depending on the modeling assumptions. Our findings show that
the choice of modeling can have a huge impact on integral experimental
covariance matrices. When the latter are used in a validation procedure to
derive a bias, this procedure can be affected by the choice of modeling
assumptions, too. The correct consideration of correlated data seems to be
inevitable if the experimental data in a validation procedure is limited or one
cannot rely on a sufficient number of uncorrelated data sets, e.g. from
different laboratories using different setups etc.


title:
Characterization of the equilibrium configuration for modulated beams in
  a plasma wakefield accelerator

abstract:
  We analyze the equilibrium configuration for a modulated beam with sharp
boundaries exposed to the fields self-generated by the interaction with a
plasma. Through a semi-analytical approach we show the presence of multiple
equilibrium configurations and we determine the one more suitable for wakefield
excitation. Once pointed out the absence of confinement for the front of the
beam and the consequently divergence driven by the emittance, we study the
evolution of the equilibrium configuration while propagating in the plasma,
discarding all the others time-dependencies. We show the onset of a rigid
backward drift of the equilibrium configuration and we provide an explanation
in the increasing length of the first bunch.


title: Einstein's Discovery of Gravitational Waves 1916-1918

abstract:
  In his 1916 ground-breaking general relativity paper Einstein had imposed a
restrictive coordinate condition, his field equations were valid for coordinate
systems which are unimodular. Later, Einstein published a paper on
gravitational waves. The solution presented in this paper did not satisfy the
above restrictive condition. In his gravitational waves paper, Einstein
concluded that gravitational fields propagate at the speed of light. The
solution is the Minkowski flat metric plus a small disturbance propagating in a
flat spacetime. Einstein calculated the small deviation from Minkowski metric
in a manner analogous to that of retarded potentials in electrodynamics.
However, in obtaining the above derivation, Einstein made a mathematical error.
This error caused him to obtain three different types of waves compatible with
his approximate field equations: longitudinal waves, transverse waves and a new
type of wave. Einstein added an Addendum in which he suggested that in systems
in unimodular coordinates only waves of the third type occur and these waves
transport energy. He became obsessed with his unimodular coordinates.
Einstein's colleagues demonstrated to him that in the coordinate system in
unimodular coordinates the gravitational wave of a mass point carry no energy,
but Einstein tried to persuade them that he had actually not made a mistake in
his gravitational waves paper. Einstein, however, eventually accepted his
colleagues results and dropped the restrictive unimodular coordinates. This
finally led him to discover plane transverse gravitational waves.


title:
Fluid flow in a reservoir drained by a multiple fractured horizontal
  well

abstract:
  A mathematical model for computation of the fluid pressure in a reservoir
drained by a horizontal multiple fractured well is proposed. The model is
applicable for an arbitrary network of fractures with different finite
conductivities of each segment, for variable in space and time physical
parameters of the reservoir and for different field development plans. The
variational formulation of the model allows effective numerical simulation
using the finite element method. Case studies demonstrate how the main flow
characteristics (well productivity, pressure distribution) depend on the
geometrical and physical characteristics of the reservoir and of the fracture
network. The presented model is suitable for estimation of the productivity of
a multiple fractured well and as an optimization tool for efficient reservoir
development.


title: Packing and Covering Immersion Models of Planar subcubic Graphs

abstract:
  A graph $H$ is an immersion of a graph $G$ if $H$ can be obtained by some
sugraph $G$ after lifting incident edges. We prove that there is a polynomial
function $f:\Bbb{N}\times\Bbb{N}\rightarrow\Bbb{N}$, such that if $H$ is a
connected planar subcubic graph on $h>0$ edges, $G$ is a graph, and $k$ is a
non-negative integer, then either $G$ contains $k$ vertex/edge-disjoint
subgraphs, each containing $H$ as an immersion, or $G$ contains a set $F$ of
$f(k,h)$ vertices/edges such that $G\setminus F$ does not contain $H$ as an
immersion.


title:
Dynamics of mechanical systems with multiple sliding contacts: new faces
  of Painlev\'e's paradox

abstract:
  We investigate the dynamics of finite degree-of-freedom, planar mechanical
systems with multiple sliding, unilateral frictional point contacts. A complete
classification of systems with 2 sliding contacts is given. The contact-mode
based approach of rigid body mechanics is combined with linear stability
analysis using a compliant contact model to determine the feasibility and the
stability of every possible contact mode in each class. Special forms of
non-stationary contact dynamics including "impact without collision" and
"reverse chattering" are also investigated. Many types of solution
inconsistency and the indeterminacy are identified and new phenomena related to
Painlev\'e"s non-existence and non-uniqueness paradoxes are discovered. Among
others, we show that the non-existence paradox is not fully resolvable by
considering impulsive contact forces. These results contribute to a growing
body of evidence that rigid body mechanics cannot be developed into a complete
and self-consistent theory in the presence of contacts and friction.


title:
Field-induced dissociation of excitons in two-dimensional MoS$_{2}$/hBN
  heterostructures

abstract:
  Atomically thin semi-conductors are characterized by strongly bound excitons
which govern the optical properties of the materials below and near the band
edge. Efficient conversion of photons into electrical current requires, as a
first step, the dissociation of the exciton into free electrons and holes. Here
we calculate the dissociation rates of excitons in monolayer MoS$_2$ as a
function of an applied in-plane electric field. The dissociation rates are
obtained as the inverse lifetime of the resonant states of a two-dimensional
Hydrogenic Hamiltonian which describes the exciton within the Mott-Wannier
model. The resonances are computed using complex scaling, and the effective
masses and screened electron-hole interaction defining the Hydrogenic
Hamiltonian are computed from first-principles. For field strengths above 0.1
V/nm the dissociation lifetime is shorter than 1 picosecond, which is shorter
than the lifetime of other, competing, decay mechanisms. Interestingly,
encapsulation of the \moly layer in just two layers of hBN, enhances the
dissociation rate by around one order of magnitude due to the increased
screening showing that dielectric engineering is an effective way to control
exciton lifetimes in two-dimensional materials.


title: Scattering theory for Lindblad master equations

abstract:
  We study scattering theory for a quantum-mechanical system consisting of a
particle scattered off a dynamical target that occupies a compact region in
position space. After taking a trace over the degrees of freedom of the target,
the dynamics of the particle is generated by a Lindbladian acting on the space
of trace-class operators. We study scattering theory for a general class of
Lindbladians with bounded interaction terms. First, we consider models where a
particle approaching the target is always re-emitted by the target. Then we
study models where the particle may be captured by the target. An important
ingredient of our analysis is a scattering theory for dissipative operators on
Hilbert space.


title:
Relaxation of the resistive superconducting state in boron-doped diamond
  films

abstract:
  We report a study of the relaxation time of the restoration of the resistive
superconducting state in single crystalline boron-doped diamond using
amplitude-modulated absorption of (sub-)THz radiation (AMAR). The films grown
on an insulating diamond substrate have a low carrier density of about
2.5x10^{21} cm^{-3} and a critical temperature of about 2 K. By changing the
modulation frequency we find a high-frequency rolloff which we associate with
the characterstic time of energy relaxation between the electron and the phonon
systems or the relaxation time for nonequilibrium superconductivity. Our main
result is that the electron-phonon scattering time varies clearly as T^{-2},
over the accessible temperature range of 1.7 to 2.2 K. In addition, we find,
upon approaching the critical temperature T_c, evidence for an increasing
relaxation time on both sides of T_c.


title: Derivation of the magnetic Euler-Heisenberg energy

abstract:
  In quantum field theory, the vacuum is a fluctuating medium which behaves as
a nonlinear polarizable material. In this article, we perform the first
rigorous derivation of the magnetic Euler-Heisenberg effective energy, a
nonlinear functional that describes the effective fluctuations of the quantum
vacuum in a classical magnetic field. We start from a classical magnetic field
in interaction with a quan-tized Dirac field in its ground state, and we study
a limit in which the classical magnetic field is slowly varying. After a change
of scales, this is equivalent to a semi-classical limit $\hbar\to0$, with a
strong magnetic field of order $1/\hbar$. In this regime, we prove that the
energy of Dirac's polarized vacuum converges to the Euler-Heisenberg
functional. The model has ultraviolet divergences, which we regularize using
the Pauli-Villars method. We also discuss how to remove the regularization of
the Euler-Heisenberg effective Lagrangian, using charge renormaliza-tion,
perturbatively to any order of the coupling constant.


title: Renormalisation group analysis of 4D spin models and self-avoiding walk

abstract:
  We give an overview of results on critical phenomena in 4 dimensions,
obtained recently using a rigorous renormalisation group method. In particular,
for the $n$-component $|\varphi|^4$ spin model in dimension 4, with small
coupling constant, we prove that the susceptibility diverges with a logarithmic
correction to the mean-field behaviour with exponent $(n+2)/(n+8)$. This result
extends rigorously to $n=0$, interpreted as a supersymmetric version of the
model that represents exactly the continuous-time weakly self-avoiding walk. We
also analyse the critical two-point function of the weakly self-avoiding walk,
the specific heat and pressure of the $|\varphi|^4$ model, as well as scaling
limits of the spin field close to the critical point.


title: Tracking the performance of an R&D programme in the Biomedical Sciences

abstract:
  This paper aims at offering an evaluation framework of an Research and
Development programme in the Biomedical Sciences. It showcases the Spanish
Biomedical Research Networking Centres initiative (CIBER) as an example of the
effect of research policy management on performance. For this it focuses on
three specific aspects: its role on the national research output in the
biomedical sciences, its effect on promoting translational research through
internal collaboration between research groups, and the perception of
researchers on the programme as defined by their inclusion of their CIBER
centres in the address field. Research output derived from this programme
represents around 25 per cent of the country's publications in the biomedical
fields. After analysing a seven year period, the programme has enhanced
collaborations between its members, but they do not seem to be sufficiently
strong. With regard to the credit given to the initiative, 54.5 per cent of the
publications mentioned this programme in their address, however an increase on
the share of papers mention it is observed two years after it was launched. We
suggest that by finding the point in which the share of mentions stabilises may
be a good strategy to identify the complete fulfilment of these types of
Research and Development policies.


title: Spinor Structure and Matter Spectrum

abstract:
  Classification of relativistic wave equations is given on the ground of
interlocking representations of the Lorentz group. A system of interlocking
representations is associated with a system of eigenvector subspaces of the
energy operator. Such a correspondence allows one to define matter spectrum,
where the each level of this spectrum presents a some state of elementary
particle. An elementary particle is understood as a superposition of state
vectors in nonseparable Hilbert space. Classification of indecomposable systems
of relativistic wave equations is produced for bosonic and fermionic fields on
an equal footing (including Dirac and Maxwell equations). All these fields are
equivalent levels of matter spectrum, which differ from each other by the value
of mass and spin. It is shown that a spectrum of the energy operator,
corresponding to a given matter level, is non-degenerate for the fields of type
$(l,0)\oplus(0,l)$, where $l$ is a spin value, whereas for arbitrary spin
chains we have degenerate spectrum. Energy spectra of the stability levels
(electron and proton states) of the matter spectrum are studied in detail. It
is shown that these stability levels have a nature of threshold scales of the
fractal structure associated with the system of interlocking representations of
the Lorentz group.


title:
Effects of suprathermal electrons on the proton temperature anisotropy
  in space plasmas: Electromagnetic ion-cyclotron instability

abstract:
  In collision-poor plasmas from space, e.g., the solar wind and planetary
magnetospheres, the kinetic anisotropy of the plasma particles is expected to
be regulated by the kinetic instabilities. Driven by an excess of ion (proton)
temperature perpendicular to the magnetic field $(~T_\perp >T_\parallel)$, the
electromagnetic ion-cyclotron (EMIC) instability is fast enough to constrain
the proton anisotropy, but the observations do not conform to the instability
thresholds predicted by the standard theory for bi-Maxwellian models of the
plasma particles. This paper presents an extended investigation of the EMIC
instability in the presence of suprathermal electrons which are ubiquitous in
these environments. The analysis is based on the kinetic (Vlasov-Maxwell)
theory assuming that both species, protons and electrons, may be anisotropic,
and the EMIC unstable solutions are derived numerically providing an accurate
description for conditions typically encountered in space plasmas. The effects
of suprathermal populations are triggered by the electron anisotropy and the
temperature contrast between electrons and protons. For certain conditions the
anisotropy thresholds exceed the limits of the proton anisotropy measured in
the solar wind considerably restraining the unstable regimes of the EMIC modes.


title:
Image Restoration and Reconstruction using Variable Splitting and
  Class-adapted Image Priors

abstract:
  This paper proposes using a Gaussian mixture model as a prior, for solving
two image inverse problems, namely image deblurring and compressive imaging. We
capitalize on the fact that variable splitting algorithms, like ADMM, are able
to decouple the handling of the observation operator from that of the
regularizer, and plug a state-of-the-art algorithm into the pure denoising
step. Furthermore, we show that, when applied to a specific type of image, a
Gaussian mixture model trained from an database of images of the same type is
able to outperform current state-of-the-art methods.


title:
Comparison of linear and non-linear monotononicity-based shape
  reconstruction using exact matrix characterizations

abstract:
  Detecting inhomogeneities in the electrical conductivity is a special case of
the inverse problem in electrical impedance tomography, that leads to fast
direct reconstruction methods. One such method can, under reasonable
assumptions, exactly characterize the inhomogeneities based on monotonicity
properties of either the Neumann-to-Dirichlet map (non-linear) or its Fr\'echet
derivative (linear). We give a comparison of the non-linear and linear approach
in the presence of measurement noise, and show numerically that the two methods
give essentially the same reconstruction in the unit disk domain. For a fair
comparison, exact matrix characterizations are used when probing the
monotonicity relations to avoid errors from numerical solution to PDEs and
numerical integration. Using a special factorization of the
Neumann-to-Dirichlet map also makes the non-linear method as fast as the linear
method in the unit disk geometry.


title:
Topological end states in two-orbital double-exchange model for colossal
  magnetoresistive manganites

abstract:
  Manganites are famous mostly for the colossal magnetoresistive effect, which
involves the phase separation between ferromagnetic phase and charge-ordered
CE-type antiferromagnetic phases. Furthermore, manganites contain some typical
magnetic ferroelectrics, e.g. E-type antiferromagnetic $o$-HoMnO$_3$. Here we
re-examined these zigzag-winding antiferromagnetic phases (CE-type and E-type
antiferromagnets) from the topological perspective. Our theoretical analysis
proved that the E-type phase is a weak topological insulator belonging to the
$\mathbb{Z}$ class. In momentum space, we classify the symmetries of this
phase, and find the three symmetry operators for the chiral, particle-hole, and
time-reversal symmetry. The CE-type phase can be described by the
Duffin-Kemmer-Petiau algebra, implying that it is a new class of topological
insulator and hence extends the existing classification. The corresponding
topological end states are demonstrated via numerical calculations, which may
implicate the experimental observed ferromagnetic edge states in manganite
strips (Nat. Commun. 6, 6179 (2015)) and may play a crucial role in the
colossal magnetoresistive effect.


title:
On the Higher Dimensional Quasi-Power Theorem and a Berry-Esseen
  Inequality

abstract:
  Hwang's quasi-power theorem asserts that a sequence of random variables whose
moment generating functions are approximately given by powers of some analytic
function is asymptotically normally distributed. This theorem is generalised to
higher dimensional random variables. To obtain this result, a higher
dimensional analogue of the Berry-Esseen inequality is proved, generalising a
two-dimensional version of Sadikova.


title: Control-Flow Integrity: Precision, Security, and Performance

abstract:
  Memory corruption errors in C/C++ programs remain the most common source of
security vulnerabilities in today's systems. Control-flow hijacking attacks
exploit memory corruption vulnerabilities to divert program execution away from
the intended control flow. Researchers have spent more than a decade studying
and refining defenses based on Control-Flow Integrity (CFI), and this technique
is now integrated into several production compilers. However, so far no study
has systematically compared the various proposed CFI mechanisms, nor is there
any protocol on how to compare such mechanisms.
  We compare a broad range of CFI mechanisms using a unified nomenclature based
on (i) a qualitative discussion of the conceptual security guarantees, (ii) a
quantitative security evaluation, and (iii) an empirical evaluation of their
performance in the same test environment. For each mechanism, we evaluate (i)
protected types of control-flow transfers, (ii) the precision of the protection
for forward and backward edges. For open-source compiler-based implementations,
we additionally evaluate (iii) the generated equivalence classes and target
sets, and (iv) the runtime performance.


title:
Weak error estimates for trajectories of SPDEs for Spectral Galerkin
  discretization

abstract:
  We consider stochastic semi-linear evolution equations which are driven by
additive, spatially correlated, Wiener noise, and in particular consider
problems of heat equation (analytic semigroup) and damped-driven wave equations
(bounded semigroup) type. We discretize these equations by means of a spectral
Galerkin projection, and we study the approximation of the probability
distribution of the trajectories: test functions are regular, but depend on the
values of the process on the interval $[0,T]$.
  We introduce a new approach in the context of quantative weak error analysis
for discretization of SPDEs. The weak error is formulated using a deterministic
function (It\^o map) of the stochastic convolution found when the nonlinear
term is dropped. The regularity properties of the It\^o map are exploited, and
in particular second-order Taylor expansions employed, to transfer the error
from spectral approximation of the stochastic convolution into the weak error
of interest.
  We prove that the weak rate of convergence is twice the strong rate of
convergence in two situations. First, we assume that the covariance operator
commutes with the generator of the semigroup: the first order term in the weak
error expansion cancels out thanks to an independence property. Second, we
remove the commuting assumption, and extend the previous result, thanks to the
analysis of a new error term depending on a commutator.


title: Quantum decision theory in simple risky choices

abstract:
  Quantum decision theory (QDT) is a recently developed theory of decision
making based on the mathematics of Hilbert spaces, a framework known in physics
for its application to quantum mechanics. This framework formalizes the concept
of uncertainty and other effects that are particularly manifest in cognitive
processes, which makes it well suited for the study of decision making. QDT
describes a decision maker's choice as a stochastic event occurring with a
probability that is the sum of an objective utility factor and a subjective
attraction factor. QDT offers a prediction for the average effect of
subjectivity on decision makers, the quarter law. We examine individual and
aggregated (group) data, and find that the results are in good agreement with
the quarter law at the level of groups. At the individual level, it appears
that the quarter law could be refined in order to reflect individual
characteristics. This article revisits the formalism of QDT along a concrete
example and offers a practical guide to researchers who are interested in
applying QDT to a dataset of binary lotteries in the domain of gains.


title: Upper bounds on probability thresholds for asymmetric Ramsey properties

abstract:
  Given two graphs $G$ and $H$, we investigate for which functions $p=p(n)$ the
random graph $G_{n,p}$ (the binomial random graph on $n$ vertices with edge
probability $p$) satisfies with probability $1-o(1)$ that every
red-blue-coloring of its edges contains a red copy of $G$ or a blue copy of
$H$. We prove a general upper bound on the threshold for this property under
the assumption that the denser of the two graphs satisfies a certain
balancedness condition. Our result partially confirms a conjecture by the first
author and Kreuter, and together with earlier lower bound results establishes
the exact order of magnitude of the threshold for the case in which $G$ and $H$
are complete graphs of arbitrary size.
  In our proof we present an alternative to the so-called deletion method,
which was introduced by R\"odl and Ruci\'{n}ski in their study of symmetric
Ramsey properties of random graphs (i.e. the case $G=H$), and has been used in
many proofs of similar results since then.


title:
Discrete approximation of a mixture distribution via restricted
  divergence

abstract:
  Mixture distributions arise in many application areas, for example as
marginal distributions or convolutions of distributions. We present a method of
constructing an easily tractable discrete mixture distribution as an
approximation to a mixture distribution with a large to infinite number,
discrete or continuous, of components. The proposed DIRECT (Divergence
Restricting Conditional Tesselation) algorithm is set up such that a
pre-specified precision, defined in terms of Kullback-Leibler divergence
between true distribution and approximation, is guaranteed. Application of the
algorithm is demonstrated in two examples.


title:
Row-constrained effective sets of colourings in the $2$-fold horocyclic
  tessellations of $\mathbb{H}^2$ are sofic

abstract:
  In this article we prove that, restricted to the row-constrained case,
effective sets of colourings in the $2$-fold horocyclic tessellations of the
hyperbolic plane $\mathbb{H}^2$ are sofic.


title: Using Deep Q-Learning to Control Optimization Hyperparameters

abstract:
  We present a novel definition of the reinforcement learning state, actions
and reward function that allows a deep Q-network (DQN) to learn to control an
optimization hyperparameter. Using Q-learning with experience replay, we train
two DQNs to accept a state representation of an objective function as input and
output the expected discounted return of rewards, or q-values, connected to the
actions of either adjusting the learning rate or leaving it unchanged. The two
DQNs learn a policy similar to a line search, but differ in the number of
allowed actions. The trained DQNs in combination with a gradient-based update
routine form the basis of the Q-gradient descent algorithms. To demonstrate the
viability of this framework, we show that the DQN's q-values associated with
optimal action converge and that the Q-gradient descent algorithms outperform
gradient descent with an Armijo or nonmonotone line search. Unlike traditional
optimization methods, Q-gradient descent can incorporate any objective
statistic and by varying the actions we gain insight into the type of learning
rate adjustment strategies that are successful for neural network optimization.


title: Combinatorial degenerations of surfaces and Calabi--Yau threefolds

abstract:
  In this article we study combinatorial degenerations of minimal surfaces of
Kodaira dimension 0 over local fields, and in particular show that the `type'
of the degeneration can be read off from the monodromy operator acting on a
suitable cohomology group. This can be viewed as an arithmetic analogue of
results of Persson and Kulikov on degenerations of complex surfaces, and
extends various particular cases studied by Matsumoto, Liedtke/Matsumoto and
Hern\'andez-Mada. We also study `maximally unipotent' degenerations of
Calabi--Yau threefolds, following Koll\'ar/Xu, showing in this case that the
dual intersection graph is a 3-sphere.


title: CASCADE - a multi-layer Boron-10 neutron detection system

abstract:
  The globally increased demand for helium-3 along with the limited
availability of this gas calls for the development of alternative technologies
for the large ESS instrumentation pool. We report on the CASCADE Project - a
novel detection system, which has been developed for the purposes of neutron
spin echo spectroscopy. It features 2D spatially resolved detection of thermal
neutrons at high rates. The CASCADE detector is composed of a stack of solid
boron-10 coated Gas Electron Multiplier foils, which serve both as a neutron
converter and as an amplifier for the primary ionization deposited in the
standard Argon-CO2 counting gas environment. This multi-layer setup efficiently
increases the detection efficiency and serves as a helium-3 alternative. It has
furthermore been possible to extract the signal of the charge traversing the
stack to identify the very thin conversion layer of about 1 micrometer. This
allows the precise determination of the time-of-flight, necessary for the
application in MIEZE spin echo techniques.


title:
Recent Progress in Molecular Simulation of Aqueous Electrolytes: Force
  Fields, Chemical Potentials and Solubility

abstract:
  Although aqueous electrolytes are among the most important solutions, the
molecular simulation of their intertwined properties of chemical potentials,
solubility and activity coefficients has remained a challenging problem, and
has attracted considerable recent interest. In this perspectives review, we
focus on the simplest case of aqueous sodium chloride at ambient conditions and
discuss the two main factors that have impeded progress. The first is lack of
consensus with respect to the appropriate methodology for force field (FF)
development. We examine how most commonly used FFs have been developed, and
emphasize the importance of distinguishing between "Training Set Properties"
used to fit the FF parameters, and "Test Set Properties", which are pure
predictions of additional properties. The second is disagreement among
solubility results obtained, even using identical FFs and thermodynamic
conditions. Solubility calculations have been approached using both
thermodynamic--based methods and direct molecular dynamics--based methods
implementing coexisting solution and solid phases. Although convergence has
been very recently achieved among results based on the former approach, there
is as yet no general agreement with simulation results based on the latter
methodology. We also propose a new method to directly calculate the electrolyte
standard chemical potential in the Henry-Law ideality model. We conclude by
making recommendations for calculating solubility, chemical potentials and
activity coefficients, and outline a potential path for future progress.


title:
Charged Plate in Asymmetric Electrolytes: One-loop Renormalization of
  Surface Charge Density and Debye Length due to Ionic Correlations

abstract:
  The self-consistent field theory (SCFT) is used to study the mean potential
near a charged plate inside a $m:-n$ electrolyte. A perturbation series is
developed in terms of $g = 4 \pi b/\ell_{\rm {\scriptscriptstyle DB}}$, where
$b, \ell_{\rm{\scriptscriptstyle DB}}$ are Bjerrum length and {\em bare} Debye
length respectively. To the zeroth order, we obtain nonlinear Poisson-Boltzmann
theory. For asymmetric electrolytes ($m \neq n$), the first order (one-loop)
correction to mean potential contains a {\em secular term}, which indicates the
breakdown of regular perturbation method. Using a renormalizaton group
transformation (RG), we remove the secular term and obtain a globally
well-behaved one-loop approximation with {\em a renormalized Debye length} and
{\em a renormalized surface charge density}. Furthermore, we find that if the
counter-ions are multivalent, the surface charge density is renormalized
substantially {\em downwards}, and may undergo a change of sign, if the bare
surface charge density is sufficiently large.


title: Rotating Anisotropic Fluid Solutions

abstract:
  An exact rotating anisotropic fluid solution and a family of exact rotating
anisotropic fluid solutions are presented which satisfy all energy conditions
for certain values of their parameters. The components of the Ricci tensor the
eigenvalues of this tensor and the energy-momentum tensor of the solutions are
given explicitly. All have the ring singularity of Kerr's solution and in
addition the solution one more singularity and some solutions of the family
additional singularities.The solution matches to the extremal solution of Kerr
on two surfaces, which are thin shells and for proper values of the parameters
of the solution approximate oblate spheroids. One of these surfaces has
positive surface density. The solutions of the family satisfy the matching
conditions with the solution of Kerr on two pair of surfaces, which are again
thin shells. The surface density of one pair of surfaces is given explicitly.
Also for proper values of the parameters of the solutions the surfaces of the
other pair approximate oblate spheroids.


title: Circumstellar Disks of the Most Vigorously Accreting Young Stars

abstract:
  Young stellar objects (YSOs) may not accumulate their mass steadily, as was
previously thought, but in a series of violent events manifesting themselves as
sharp stellar brightening. These events can be caused by fragmentation due to
gravitational instabilities in massive gaseous disks surrounding young stars,
followed by migration of dense gaseous clumps onto the star. We report our high
angular resolution, coronagraphic near-infrared polarization imaging
observations using the High Contrast Instrument for the Subaru Next Generation
Adaptive Optics (HiCIAO) of the Subaru 8.2 m Telescope, towards four YSOs which
are undergoing luminous accretion outbursts. The obtained infrared images have
verified the presence of several hundred AUs scale arms and arcs surrounding
these YSOs. In addition, our hydrodynamics simulations and radiative transfer
models further demonstrate that these observed structures can indeed be
explained by strong gravitational instabilities occurring at the beginning of
the disk formation phase. The effect of those tempestuous episodes of disk
evolution on star and planet formation remains to be understood.


title:
Accretion disk dynamics: {\alpha}-viscosity in self-similar
  self-gravitating models

abstract:
  Aims: We investigate the suitability of {\alpha}-viscosity in self-similar
models for self-gravitating disks with a focus on active galactic nuclei (AGN)
disks.
  Methods: We use a self-similar approach to simplify the partial differential
equations arising from the evolution equation, which are then solved using
numerical standard procedures.
  Results: We find a self-similar solution for the dynamical evolution of
self-gravitating {\alpha}-disks and derive the significant quantities. In the
Keplerian part of the disk our model is consistent with standard stationary
{\alpha}-disk theory, and self-consistent throughout the self-gravitating
regime. Positive accretion rates throughout the disk demand a high degree of
self-gravitation. Combined with the temporal decline of the accretion rate and
its low amount, the model prohibits the growth of large central masses.
  Conclusions: {\alpha}-viscosity cannot account for the evolution of the whole
mass spectrum of super-massive black holes (SMBH) in AGN. However, considering
the involved scales it seems suitable for modelling protoplanetary disks.
  Keywords: accretion, accretion disks, turbulence, hydrodynamics, methods:
analytical


title:
Flow and Heat Transfer in Micro Pin Fin Heat Sinks with
  Nano-Encapsulated Phase Change Materials

abstract:
  In this paper, a 3D conjugated heat transfer model for Nano-Encapsulated
Phase Change Materials (NEPCMs) cooled Micro Pin Fin Heat Sink (MPFHS) is
presented. The governing equations of flow and heat transfer are solved using a
finite volume method based on collocated grid and the results are validated
with the available data reported in the literature. The effect of nanoparticles
volume fraction (C = 0.1, 0.2, 0.3), inlet velocity (Vin = 0.015, 0.030, 0.045
m/s), and bottom wall temperature (Twall = 299.15, 303.15, 315.15, 350.15 K)
are studied on Nusselt and Euler numbers as well as temperature contours in the
system. The results indicate that significant heat transfer enhancement is
achieved when using NEPCM slurry as an advanced coolant. The maximum Nusselt
number when NEPCM slurry (C = 0.3) with Vin = 0.015, 0.030, 0.045 (m/s) is
employed, are 2.27, 1.81, 1.56 times higher than the ones with base fluid,
respectively. However, with increasing bottom wall temperature, the Nusselt
number first increases then decreases. The former is due to higher heat
transfer capability of coolant at temperatures over the melting range of PCM
particles due to partial melting of nanoparticles in this range. While, the
latter phenomena is due to the lower capability of NEPCM particles and
consequently coolant in absorbing heat at coolant temperatures higher than the
temperature correspond to fully melted NEPCM. It was observed that NEPCM slurry
has a drastic effect on Euler number, and with increasing volume fraction and
decreasing inlet velocity, the Euler number increases accordingly.


title: Weak Solutions for Singular Quasilinear Elliptic Systems

abstract:
  We investigate the quasilinear elliptic system $-\Delta_{m} u&=u^{-p}v^{-q}$,
$u>0 \quad\mbox{ in } \Omega$, $-\Delta_{m} v&=u^{r}v^{-s}$, $v>0 \quad\mbox{
in }\Omega$,
  $u=v=0 \quad\mbox{ on } \partial{\Omega}$,
  where $\Omega \subset{\mathbb R}^{N}(N\geq 1)$ is a bounded and smooth
domain, $1<m<\infty, p, q, r, s>0$. Under certain conditions imposed on the
exponents we obtain the existence and uniqueness of a weak solution $(u, v)$
with $u, v \in W_{0}^{1, m}(\Omega)\cap C(\Omega)$. We also investigate the
$W_{0}^{1, \tau}(\Omega)$ regularity of solution and determine the optimal
range of $\tau \geq m$ for such regularity.


title: High-precision force sensing using a single trapped ion

abstract:
  We introduce quantum sensing schemes for measuring very weak forces with a
single trapped ion. They use the spin-motional coupling induced by the
laser-ion interaction to transfer the relevant force information to the
spin-degree of freedom. Therefore, the force estimation is carried out simply
by observing the Ramsey-type oscillations of the ion spin states. Three quantum
probes are considered, which are represented by systems obeying the
Jaynes-Cummings, quantum Rabi (in 1D) and Jahn-Teller (in 2D) models. By using
dynamical decoupling schemes in the Jaynes-Cummings and Jahn-Teller models, our
force sensing protocols can be made robust to the spin dephasing caused by the
thermal and magnetic field fluctuations. In the quantum-Rabi probe, the
residual spin-phonon coupling vanishes, which makes this sensing protocol
naturally robust to thermally-induced spin dephasing. We show that the proposed
techniques can be used to sense the axial and transverse components of the
force with a sensitivity beyond the yN $/\sqrt{\text{Hz}}$ range, i.e. in the
xN$ /\sqrt{\text{Hz}}$ (xennonewton, $10^{-27}$). The Jahn-Teller protocol, in
particular, can be used to implement a two-channel vector spectrum analyzer for
measuring ultra-low voltages.


title: Quantum tomography via Non-orthogonal basis and weak values

abstract:
  Using a relation between a bi-orthogonal set of equiseparable bases and the
weak values of the density matrix we derive an explicit formula for its
tomographic reconstruction completely analogous to the standard mutually
unbiased bases expansion. With the simple example of a qubit is evidenced the
relationship between weak values, measured probabilities and the separation
between non-orthogonal bases.


title:
DAMA confronts null searches in the effective theory of dark
  matter-nucleon interactions

abstract:
  We examine the dark matter interpretation of the modulation signal reported
by the DAMA experiment from the perspective of effective field theories
displaying Galilean invariance. We consider the most general effective coupling
leading to the elastic scattering of a dark matter particle with spin 0 or 1/2
off a nucleon, and we analyze the compatibility of the DAMA signal with the
null results from other direct detection experiments, as well as with the
non-observation of a high energy neutrino flux in the direction of the Sun from
dark matter annihilation. To this end, we develop a novel semi-analytical
approach for comparing experimental results in the high-dimensional parameter
space of the non-relativistic effective theory. Assuming the standard halo
model, we find a strong tension between the dark matter interpretation of the
DAMA modulation signal and the null result experiments. We also list possible
ways-out of this conclusion.


title:
From 3D static order to 2D dynamic correlations in the tetragonal double
  perovskite Sr2CuWO6

abstract:
  \SCWO is a tetragonal ($I4/m$) double perovskite with diamagnetic W$^{6+}$
(5d$^0$) and (Jahn-Teller-active) Cu$^{2+}$ (3$d^9$) in a rocksalt-ordered
arrangement on the B sites, modelling an anisotropic fcc-lattice
antiferromagnet with $S=1/2$. We have studied the magnetic structure, dynamics
and thermodynamic properties of this material above and below the
\Neel{}-ordering transition at $T_{\textrm{N}} = 24$~K. Muon spin relaxation
spectroscopy, neutron diffraction and neutron spectroscopy experiments show
that the transition at $T_{\textrm{N}}$ on heating is from static 3D type-2
antiferromagnetism to 2D dynamic correlations that remain detectable up to
100~K. Above $T_{\textrm{N}}$ the muon relaxation is described by a compressed
exponential decay, revealing a strong correlation between the spin fluctuation
rate and the 2D correlation length. The low-temperature muon data and the
entropy release around $T_{\textrm{N}}$ as obtained from the heat capacity data
point to small magnetic domains, probably of the order of 60~\AA{}. We note
that the material behaves more like a quasi-2D square lattice antiferromagnet
than could be expected considering its structure only. A possible explanation
might lie in the unusual strong spin-orbit-coupled magnetism of the W 5$d$
levels, as the dominant exchange interaction is via the Cu-O-W-O-Cu pathway.


title: Labelling vertices to ensure adjacency coincides with disjointness

abstract:
  Given a set of nonempty subsets of some universal set, their intersection
graph is defined as the graph with one vertex for each set and two vertices are
adjacent precisely when their representing sets have non-empty intersection.
Sometimes these sets are finite, but in many well known examples like geometric
graphs (including interval graphs) they are infinite. One can also study the
reverse problem of expressing the vertices of a given graph as distinct sets in
such a way that adjacency coincides with intersection of the corresponding
sets. The sets are usually required to conform to some template, depending on
the problem, to be either a finite set, or some geometric set like intervals,
circles, discs, cubes etc. The problem of representing a graph as an
intersection graph of sets was first introduced by Erdos and they looked at
minimising the underlying universal set necessary to represent any given graph.
In that paper it was shown that the problem is NP complete. In this paper we
study a natural variant of this problem which is to consider graphs where
vertices represent distinct sets and adjacency coincides with disjointness.
Although this is really the same problem on the complement graph, for specific
families of graphs this is a more natural way of viewing it. When taken across
the spectrum of all graphs the two problems are evidently identical. Our
motivation to look at disjointness instead of intersection is that several well
known graphs like the Petersen graph and Knesser graphs are expressed in the
latter method, and the complements of these families are not well studied. The
parameters we take into account are the maximum size of an individual vertex
label, minimum universe size possible (disregarding individual label sizes) and
versions of these two where it is required that each vertex gets labels of the
same size.


title:
Detection of Linearly Polarized 6.9 mm Continuum Emission from the Class
  0 Young Stellar Object NGC1333 IRAS4A

abstract:
  We report new Karl G. Jansky Very Large Array (JVLA), 0$"$.5 angular
resolution observations of linearly polarized continuum emission at 6.9 mm,
towards the Class 0 young stellar object (YSO) NGC1333 IRAS4A. This target
source is a collapsing dense molecular core, which was resolved at short
wavelengths to have hourglass shaped B-field configuration. We compare these
6.9 mm observations with previous polarization Submillimeter Array (SMA)
observations at 0.88 mm, which have comparable angular resolution
($\sim$0$"$7). We found that at the same resolution, the observed polarization
position angles at 6.9 mm are slightly deviated from those observed at 0.88 mm.
Due to the lower optical depth of the emission at 6.9 mm, and the potential
effect of dust grain growth, the new JVLA observations are likely probing
B-field alignments in regions interior to those sampled by the previous
polarization observations at higher frequencies. Our understanding can be
improved by more sensitive observations, and observations for the more extended
spatial scales.


title: Active colloids at fluid interfaces

abstract:
  If an active Janus particle is trapped at the interface between a liquid and
a fluid, its self-propelled motion along the interface is affected by a net
torque on the particle due to the viscosity contrast between the two adjacent
fluid phases. For a simple model of an active, spherical Janus colloid we
analyze the conditions under which translation occurs along the interface and
we provide estimates of the corresponding persistence length. We show that
under certain conditions the persistence length of such a particle is
significantly larger than the corresponding one in the bulk liquid, which is in
line with the trends observed in recent experimental studies.


title: $J$-invariant of hermitian forms over quadratic extensions

abstract:
  We develop the version of the $J$-invariant for hermitian forms over
quadratic extensions in a similar way Alexander Vishik did it for quadratic
forms. This discrete invariant contains informations about rationality of
algebraic cycles on the maximal unitary grassmannian associated with a hermitan
form over a quadratic extension. The computation of the canonical $2$-dimension
of this grassmannian in terms of the $J$-invariant is provided, as well as a
complete motivic decomposition.


title: On Methods for Transforming and Solving Finite Series

abstract:
  In this work we present new methods for transforming and solving finite
series by using the Laplace transform. In addition we introduce both an
alternative method based on the Fourier transform and a simplified approach.
The latter allows a quick solution in some cases.


title: Ion trap analogue of particle creation in black holes and cosmology

abstract:
  We consider the transversal modes of ions in a linear radio frequency (rf)
trap where we control the time dependent axial confinement to show that we can
excite quanta of motion via a two-mode squeezing process. This effect is
analogous to phenomena predicted to occur during the evaporation of black holes
and cosmological particle creation, in general out of reach for experimental
investigation. As substantial advantage of this proposal in comparison to
previous ones we propose to exploit radial and axial modes simultaneously to
permit experimental access of these effects based on state-of-the-art
technology. In addition, we propose to create and explore entanglement,
starting with two ions, and relate the results to fundamental aspects of the
entropy of black holes.


title:
On the phase-shift parameterization and ANC extraction from
  elastic-scattering data

abstract:
  We develop a method to parameterize elastic-scattering phase-shifts for
charged nuclei, based on Pad\'e expansions of a simplified effective-range
function. The method is potential independent and the input is reduced to
experimental phase shifts and bound-state energies. It allows a simple
calculation of resonance properties and of asymptotic normalization constants
(ANCs) of subthreshold bound states. We analyze the $1^-$ and $2^+$ phase
shifts of the $^{12}$C$+\alpha$ system and extract the ANCs of the
corresponding bound states. For the $1^-$ state, a factor-3 improvement with
respect to the best value available today is obtained, with a factor-10
improvement in reach. For the $2^+$ state, no improvement is obtained due to
relatively larger error bars on the experimental phase shifts.


title:
Non-Adiabatic Dynamics around a Conical Intersection with
  Surface-Hopping Coupled Coherent States

abstract:
  An extension of the CCS-method [Chem. Phys. 2004, 304, p. 103-120] for
simulating non-adiabatic dynamics with quantum effects of the nuclei is put
forward.
  The time-dependent Schr\"{o}dinger equation for the motion of the nuclei is
solved in a moving basis set. The basis set is guided by classical
trajectories, which can hop stochastically between different electronic
potential energy surfaces. The non-adiabatic transitions are modelled by a
modified version of Tully's fewest switches algorithm. The trajectories consist
of Gaussians in the phase space of the nuclei (coherent states) combined with
amplitudes for an electronic wave function. The time-dependent matrix elements
between different coherent states determine the amplitude of each trajectory in
the total multistate wave function; the diagonal matrix elements determine the
hopping probabilities and gradients. In this way, both intereference effects
and non-adiabatic transitions can be described in a very compact fashion,
leading to the exact solution if convergence with respect to the number of
trajectories is achieved and the potential energy surfaces are known globally.
  The method is tested on a 2D model for a conical intersection [J. Chem.
Phys., 1996, 104, p. 5517], where a nuclear wavepacket encircles the point of
degeneracy between two potential energy surfaces and intereferes with itself.
These intereference effects are absent in classical trajectory-based molecular
dynamics but can be fully incorporated if trajectories are replaced by surface
hopping coupled coherent states.


title:
The Approximate Solution of Newell Whitehead Segel and Fisher Equations
  Using The Adomian Decomposition Method

abstract:
  In the present work, we use the Adomian Decomposition method to find the
approximate solution for some cases of the Newell whitehead segel nonlinear
differential equation which was solved previously with exact solution by the
Homotopy perturbation and the Iteration methods, then we compared the results.


title: Advective and diffusive cosmic ray transport in galactic haloes

abstract:
  We present 1D cosmic ray transport models, numerically solving equations of
pure advection and diffusion for the electrons and calculating synchrotron
emission spectra. We find that for exponential halo magnetic field
distributions advection leads to approximately exponential radio continuum
intensity profiles, whereas diffusion leads to profiles that can be better
approximated by a Gaussian function. Accordingly, the vertical radio spectral
profiles for advection are approximately linear, whereas for diffusion they are
of `parabolic' shape. We compare our models with deep ATCA observations of two
edge-on galaxies, NGC 7090 and 7462, at $\lambda\lambda$ 22 and 6 cm. Our
result is that the cosmic ray transport in NGC 7090 is advection dominated with
$V=150^{+80}_{-30}~\rm km\,s^{-1}$, and that the one in NGC 7462 is diffusion
dominated with $D=3.0\pm 1.0 \times 10^{28}E_{\rm GeV}^{0.5}~\rm cm^2\,s^{-1}$.
NGC 7090 has both a thin and thick radio disc with respective magnetic field
scale heights of $h_{\rm B1}=0.8\pm 0.1$ kpc and $h_{\rm B2}=4.7\pm 1.0$ kpc.
NGC 7462 has only a thick radio disc with $h_{\rm B2}=3.8\pm 1.0$ kpc. In both
galaxies, the magnetic field scale heights are significantly smaller than what
estimates from energy equipartition would suggest. A non-negligible fraction of
cosmic ray electrons can escape from NGC 7090, so that this galaxy is not an
electron calorimeter.


title: Simulation of Metasurfaces in Finite Difference Techniques

abstract:
  We introduce a rigorous and simple method for analyzing metasurfaces, modeled
as zero-thickness electromagnetic sheets, in Finite Difference (FD) techniques.
The method consists in describing the spatial discontinuity induced by the
metasurface as a virtual structure, located between nodal rows of the Yee grid,
using a finite difference version of Generalized Sheet Transition Conditions
(GSTCs). In contrast to previously reported approaches, the proposed method can
handle sheets exhibiting both electric and magnetic discontinuities, and
represents therefore a fundamental contribution in computational
electromagnetics. It is presented here in the framework of the FD Frequency
Domain (FDFD) method but also applies to the FD Time Domain (FDTD) scheme. The
theory is supported by five illustrative examples.


title:
Enumerating representations of general unitary groups over principal
  ideal rings of length 2

abstract:
  We enumerate the number of complex irreducible representations of each degree
of general unitary groups of degree 4 over principal ideal rings of length 2.


title:
Polymorphism in $\alpha$-sexithiophene crystals: Relative stability and
  transition path

abstract:
  We present a joint theoretical and experimental study to investigate
polymorphism in $\alpha$-sexithiophene (6T) crystals. By means of
density-functional theory calculations, we clarify that the low-temperature
phase is favorable over the high-temperature one, with higher relative
stability by about 50 meV/molecule. This result is in agreement with our
thermal desorption measurements. We also propose a transition path between the
high- and low-temperature 6T polymorphs, estimating an upper bound for the
energy barrier of about 1 eV/molecule. The analysis of the electronic
properties of the investigated 6T crystal structures complements our study.


title: On minimum identifying codes in some Cartesian product graphs

abstract:
  An identifying code in a graph is a dominating set that also has the property
that the closed neighborhood of each vertex in the graph has a distinct
intersection with the set. The minimum cardinality of an identifying code, or
ID code, in a graph $G$ is called the ID code number of $G$ and is denoted
$\gid(G)$. In this paper, we give upper and lower bounds for the ID code number
of the prism of a graph, or $G\Box K_2$. In particular, we show that $\gid(G
\Box K_2) \ge \gid(G)$ and we show that this bound is sharp. We also give upper
and lower bounds for the ID code number of grid graphs and a general upper
bound for $\gid(G\Box K_2)$.


title: Classical theory of the hydrogen atom

abstract:
  It is shown that all of the basic properties of the hydrogen atom can be
consistently described in terms of classical electrodynamics instead of taking
the electron to be a particle; we consider an electrically charged classical
wave field, an "electron wave", which is held in a limited region of space by
the electrostatic field of the proton. It is shown that quantum mechanics must
be considered to be not a theory of particles but a classical field theory in
the spirit of classical electrodynamics. In this case, we are not faced with
difficulties in interpreting the results of the theory. In the framework of
classical electrodynamics, all of the well-known regularities of the
spontaneous emission of the hydrogen atom are obtained, which is usually
derived in the framework of quantum electrodynamics. It is shown that there are
no discrete states and discrete energy levels of the atom: the energy of the
atom and its states change continuously. An explanation of the conventional
corpuscular-statistical interpretation of atomic phenomena is given. It is
shown that this explanation is only a misinterpretation of continuous
deterministic processes. In the framework of classical electrodynamics, the
nonlinear Schrodinger equation is obtained, which accounts for the inverse
action of self-electromagnetic radiation of the electron wave and completely
describes the spontaneous emissions of an atom.


title: Interactive graphics for functional data analyses

abstract:
  Although there are established graphics that accompany the most common
functional data analyses, generating these graphics for each dataset and
analysis can be cumbersome and time consuming. Often, the barriers to
visualization inhibit useful exploratory data analyses and prevent the
development of intuition for a method and its application to a particular
dataset. The refund.shiny package was developed to address these issues for
several of the most common functional data analyses. After conducting an
analysis, the plot_shiny() function is used to generate an interactive
visualization environment that contains several distinct graphics, many of
which are updated in response to user input. These visualizations reduce the
burden of exploratory analyses and can serve as a useful tool for the
communication of results to non-statisticians.


title:
Plasmon-enhanced second harmonic generation in the laser-irradiated
  cubic metal nanoparticles

abstract:
  The plasmon-enhanced second harmonic generation in the subwavelength neutral
metal cubic nanoparticles is calculated for the first time in the hydrodynamic
and cold plasma approximations. The theory is developed that takes into account
all singularities of the electromagnetic field at the cubic nanoparticle
surface. The results are compared to the linear case for the nanocube and to
those for a spherical nanoparticle. In the latter case, they demonstrate very
strong enhancement of the local field strength and the second harmonic signal.


title: Enumerating fibres of commutator words over p-groups

abstract:
  We enumerate the fibres of commutator word maps over p-groups of nilpotency
class less than p with exponent p. We also give some examples and enumerate the
fibre sizes of all word maps over p-groups of class 2 with exponent p.


title: Topographical pathways guide chemical microswimmers

abstract:
  Achieving control over the directionality of active colloids is essential for
their use in practical applications such as cargo carriers in microfluidic
devices. So far, guidance of spherical Janus colloids was mainly realized using
specially engineered magnetic multilayer coatings combined with external
magnetic fields. Here, we demonstrate that step-like sub-micron topographical
features can be used as reliable docking and guiding devices for chemically
active spherical Janus colloids. For various topographic features (stripes,
squares or circular posts) docking of the colloid at the feature edge is robust
and reliable. Furthermore, the colloids move along the edges for significantly
long times, which systematically increase with fuel concentration. The observed
phenomenology is qualitatively captured by a simple continuum model of
self-diffusiophoresis near confining boundaries, indicating that the chemical
activity and associated hydrodynamic interactions with the nearby topography
are the main physical ingredients behind the observed behaviour.


title: Deterministic graph connectivity in the broadcast congested clique

abstract:
  We present deterministic constant-round protocols for the graph connectivity
problem in the model where each of the $n$ nodes of a graph receives a row of
the adjacency matrix, and broadcasts a single sublinear size message to all
other nodes. Communication rounds are synchronous. This model is sometimes
called the broadcast congested clique. Specifically, we exhibit a deterministic
protocol that computes the connected components of the input graph in $\lceil
1/\epsilon \rceil$ rounds, each player communicating $\mathcal{O}(n^{\epsilon}
\cdot \log n)$ bits per round, with $0 < \epsilon \leq 1$.
  We also provide a deterministic one-round protocol for connectivity, in the
model when each node receives as input the graph induced by the nodes at
distance at most $r>0$, and communicates $\mathcal{O}(n^{1/r} \cdot \log n)$
bits. This result is based on a $d$-pruning protocol, which consists in
successively removing nodes of degree at most $d$ until obtaining a graph with
minimum degree larger than $d$. Our technical novelty is the introduction of
deterministic sparse linear sketches: a linear compression function that
permits to recover sparse Boolean vectors deterministically.


title: A note on Hermite polynomials

abstract:
  In this paper, we consider linear differential equations satisfied by the
generating function for Hermite polynomials and derive some new identities
involving those polynomials.


title:
The explicit Mordell Conjecture for families of curves (with an appendix
  by M. Stoll)

abstract:
  In this article we prove the explicit Mordell Conjecture for large families
of curves. In addition, we introduce a method, of easy application, to compute
all rational points on curves of quite general shape and increasing genus. The
method bases on some explicit and sharp estimates for the height of such
rational points, and the bounds are small enough to successfully implement a
computer search. As an evidence of the simplicity of its application, we
present a variety of explicit examples and explain how to produce many others.
In the appendix our method is compared in detail to the classical method of
Manin-Demjanenko and the analysis of our explicit examples is carried to
conclusion.


title: Fuzzy approach for CNOT gate in quantum computation with mixed states

abstract:
  In the framework of quantum computation with mixed states, a fuzzy
representation of CNOT gate is introduced. In this representation, the
incidence of non-factorizability is specially investigated.


title:
The Conformation of Interfacially Adsorbed Ranaspumin-2 is an Arrested
  State on the Unfolding Pathway

abstract:
  Ranaspumin-2 (Rsn-2) is a surfactant protein found in the foam nests of the
t\'{u}ngara frog. Previous experimental work has led to a proposed model of
adsorption which involves an unusual clam shell-like `unhinging' of the protein
at an interface. Interestingly, there is no concomitant denaturation of the
secondary structural elements of Rsn-2 with the large scale transformation of
its tertiary structure. In this work we use both experiment and simulation to
better understand the driving forces underpinning this unusual process. We
develop a modified G\={o}-model approach where we have included explicit
representation of the side-chains in order to realistically model the
interaction between the secondary structure elements of the protein and the
interface. Doing so allows for the study of the underlying energy landscape
which governs the mechanism of Rsn-2 interfacial adsorption. Experimentally, we
study targeted mutants of Rsn-2, using the Langmuir trough, pendant drop
tensiometry and circular dichroism, to demonstrate that the clam-shell model is
correct. We find that Rsn-2 adsorption is in fact a two-step process: the
hydrophobic N-terminal tail recruits the protein to the interface after which
Rsn-2 undergoes an unfolding transition which maintains its secondary
structure. Intriguingly, our simulations show that the conformation Rsn-2
adopts at an interface is an arrested state along the denaturation pathway.
More generally, our computational model should prove a useful, and
computationally efficient, tool in studying the dynamics and energetics of
protein-interface interactions.


title: Light Curve Analysis of GSC 2750-0054 and GSC 03208-02644

abstract:
  We present the first photometric analysis for the newly discovered eclipsing
binary systems of Algole-type GSC 2750-0054 and GSC 03208-02644. Our analysis
was carried out by means of the most recent version of Wilson Devinney (WD)
code, which applies the model atmosphere by Kurucz (1993) with prescription in
pass band for the radiative treatment. The accepted light curve solutions
reveal absolute physical parameters and the spectral classifications for the
components are adopted. Distance to each system was calculated based on the
parameters of the accepted photometric solutions. Comparison with the
evolutionary models are presented.


title:
An Empirical Study on Academic Commentary and Its Implications on
  Reading and Writing

abstract:
  The relationship between reading and writing (RRW) is one of the major themes
in learning science. One of its obstacles is that it is difficult to define or
measure the latent background knowledge of the individual. However, in an
academic research setting, scholars are required to explicitly list their
background knowledge in the citation sections of their manuscripts. This unique
opportunity was taken advantage of to observe RRW, especially in the published
academic commentary scenario. RRW was visualized under a proposed topic process
model by using a state of the art version of latent Dirichlet allocation (LDA).
The empirical study showed that the academic commentary is modulated both by
its target paper and the author's background knowledge. Although this
conclusion was obtained in a unique environment, we suggest its implications
can also shed light on other similar interesting areas, such as dialog and
conversation, group discussion, and social media.


title: Estimating perimeter using graph cuts

abstract:
  We investigate the estimation of the perimeter of a set by a graph cut of a
random geometric graph. For $\Omega \subset D = (0,1)^d$, with $d \geq 2$, we
are given $n$ random i.i.d. points on $D$ whose membership in $\Omega$ is
known. We consider the sample as a random geometric graph with connection
distance $\varepsilon>0$. We estimate the perimeter of $\Omega$ (relative to
$D$) by the, appropriately rescaled, graph cut between the vertices in $\Omega$
and the vertices in $D \backslash \Omega$. We obtain bias and variance
estimates on the error, which are optimal in scaling with respect to $n$ and
$\varepsilon$. We consider two scaling regimes: the dense (when the average
degree of the vertices goes to $\infty$) and the sparse one (when the degree
goes to $0$). In the dense regime there is a crossover in the nature of
approximation at dimension $d=5$: we show that in low dimensions $d=2,3,4$ one
can obtain confidence intervals for the approximation error, while in higher
dimensions one can only obtain error estimates for testing the hypothesis that
the perimeter is less than a given number.


title:
The Method of almost convergence with operator of the form fractional
  order and applications

abstract:
  The purpose of this paper is twofold. First, basic concepts such as Gamma
function, almost convergence, fractional order difference operator and sequence
spaces are given as a survey character. Thus, the current knowledge about those
concepts are presented. Second, we construct the almost convergent spaces with
fractional order difference operator and compute dual spaces which are help us
in the characterization of matrix mappings. After we characterize to the matrix
transformations, we give some examples.


title:
An Analytical Model of the IEEE 802.3ah MAC Protocol for EPON-based
  Access Systems

abstract:
  Ethernet Passive Optical Networks (EPON) access systems are considered as an
alternative to ADSL for high speed access to the Internet. Supported by the
Ethernet First Mile Alliance and the IEEE, the MPCP protocol has been adopted
as the standardized MAC protocol for EPONs. Moreover, the IPACT dynamic
bandwidth allocation mechanism has been proposed for hierarchical multiplexing.
Today, IPACT is considered as interesting complement to MPCP for dynamic
bandwidth allocation over EPONs. In this paper, we propose an original
analytical model of the MPCP+IPACT protocol. Numerical results obtained from
this model are commented and compared to computer simulations.


title: Convolutional Radio Modulation Recognition Networks

abstract:
  We study the adaptation of convolutional neural networks to the complex
temporal radio signal domain. We compare the efficacy of radio modulation
classification using naively learned features against using expert features
which are widely used in the field today and we show significant performance
improvements. We show that blind temporal learning on large and densely encoded
time series using deep convolutional neural networks is viable and a strong
candidate approach for this task especially at low signal to noise ratio.


title:
Identities involving Bessel polynomials arising from linear differential
  equations

abstract:
  In this paper, we study linear differential equations arising from Bessel
polynomials and their applications. From these linear differential equations,
we give some new and explicit identities for Bessel polynomials.


title: A Max-Correlation White Noise Test for Weakly Dependent Time Series

abstract:
  This paper presents a bootstrapped p-value white noise test based on the
maximum correlation, for a time series that may be weakly dependent under the
null hypothesis. The time series may be prefiltered residuals. The test
statistic is a normalized weighted maximum sample correlation, where the
maximum lag increases at a rate slower than the sample size. We only require
uncorrelatedness under the null hypothesis, along with a moment contraction
dependence property that includes mixing and non-mixing sequences. We show
Shao's (2011) dependent wild bootstrap is valid for a much larger class of
processes than originally considered. It is also valid for residuals from a
general class of parametric models as long as the bootstrap is applied to a
first order expansion of the sample correlation. We prove the bootstrap
validity without exploiting extreme value theory (standard in the literature)
or recent Gaussian approximation theory. Finally, we extend Escanciano and
Lobato's (2009) automatic maximum lag selection to our setting with an
unbounded choice set, and find it works strikingly well in controlled
experiments. Our proposed test achieves accurate size under various white noise
null hypotheses and high power under various alternative hypotheses including
distant serial dependence.


title:
Nanopatterning process based on epitaxial masking for the fabrication of
  electronic and spintronic devices made of La0.67Sr0.33MnO3/LaAlO3/SrTiO3
  heterostructures with in situ interfaces

abstract:
  The fabrication of oxide electronics devices is presently hindered by the
lack of standardized and well established patterning procedures, applicable
down to the nanoscale. In this work, the authors propose a procedure to obtain
patterns with resolution around 100 nm on (La,Sr)MnO3/LaAlO3/SrTiO3
heterostructures. Our method is based on a multistep technique, which includes
wet and dry etching, epitaxial masking, and e-beam lithography. Our procedure
is devised to define independent patterns on the interfacial two dimensional
electron gas and on the metallic top electrode, while preserving an all-in situ
approach for the heterostructure growth. The authors show results on nano-scale
devices based on (La,Sr)MnO3/LaAlO3/SrTiO3, suitable for oxide spintronics
applications.


title:
Short Chains Enhance Slip of Highly Entangled Polystyrenes during Thin
  Film Dewetting

abstract:
  We investigate the effect of short chains on slip of highly entangled
polystyrenes (PS) during thin film dewetting from non-wetting fluorinated
surfaces. Binary and ternary mixtures were prepared from monodisperse PS with
weight average molecular weights $5 < M_\textrm{w} < 490$ kg/mol. Flow dynamics
and rim morphology of dewetting holes were captured using optical and atomic
force microscopy. Slip properties are assessed in the framework of hydrodynamic
models describing the rim height profile of dewetting holes. We show that short
chains with $M_\textrm{w}$ below the polymer critical molecular weight for
entanglements, $M_\textrm{c}$, can play an important role in slip of highly
entangled polymers. Among mixtures of the same $M_\textrm{w}$, those containing
chains with $M<M_\textrm{c}$ exhibit larger slip lengths as the number average
molecular weight, $M_\textrm{n}$, decreases. The slip enhancement effect is
only applicable when chains with $M<M_\textrm{c}$ are mixed with highly
entangled chains such that the content of the long chain component,
$\phi_\textrm{L}$, is dominant ($\phi_\textrm{L}<0.5$). These results suggest
that short chains affect slip of highly entangled polymers on non-wetting
surfaces due to the physical or chemical disparities of end groups, and any
associated dynamical effect their presence may have, as compared to the
backbone units. The enhanced slip in this regard is attributed to the impact of
chain end groups or short chain enrichment on the effective interfacial
friction coefficient. Accordingly, for entangled PS, a higher concentration of
end groups or short chains at the interface results in a lower effective
friction coefficient which consequently enhances the slip length.


title:
Generalized network structures: The configuration model and the
  canonical ensemble of simplicial complexes

abstract:
  Simplicial complexes are generalized network structures able to encode
interactions occurring between more than two nodes. Simplicial complexes
describe a large variety of complex interacting systems ranging from brain
networks, to social and collaboration networks. Here we characterize the
structure of simplicial complexes using their generalized degrees that capture
fundamental properties of one, two, three or more linked nodes. Moreover we
introduce the configuration model and the canonical ensemble of simplicial
complexes, enforcing respectively the sequence of generalized degrees of the
nodes and the sequence of the expected generalized degrees of the nodes. We
evaluate the entropy of these ensembles, finding the asymptotic expression for
the number of simplicial complexes in the configuration model. We provide the
algorithms for the construction of simplicial complexes belonging to the
configuration model and the canonical ensemble of simplicial complexes. We give
an expression for the structural cutoff of simplicial complexes that for
simplicial complexes of dimension $d=1$ reduces to the structural cutoff of
simple networks. Finally we provide a numerical analysis of the natural
correlations emerging in the configuration model of simplicial complexes
without structural cutoff.


title:
Internal dipolar field and soft magnons in periodic nanocomposite
  magnets

abstract:
  We study spin wave excitations in a three-dimensional nanocomposite magnet of
exchange coupled hard (SmCo$_5$) and soft (FeCo) phases. The dipolar
interaction splits the spin wave energies into the upper and lower branches of
the spin wave manifold. When the amount of the soft phase is increased the
energy of low-lying spin excitations is considerably softened due to two
reasons: (i) the low- lying mode locked into the soft phase region with a spin
wave gap at ${\bf k}= 0$ which scales approximately proportional to the
anisotropy constant of the soft phase and (ii) the internal dipolar field which
comes from magnetic charges forming at hard-soft boundaries with normals
parallel to the magnetization displaces the spin wave manifold toward the lower
energies. With adding more soft phase the spin wave gap closes and the system
moves to another ground state characterized by the magnetization mismatch
between spins of the hard and soft phases.


title: Spectral radius algebras of wce operators

abstract:
  In this paper, we investigate the spectral radius al- gebras related to the
weighted conditional expectation operators on the Hilbert spaces L2(F). We give
a large classes of operators on L2(F) that have the same spectral radius
algebra. As a con- sequence we get that the spectral radius algebras of a
weighted conditional expectation operator and its Aluthge transformation are
equal. Also, we obtain an ideal of the spectral radius algebra related to the
rank one operators on the Hilbert space H. Finally we get that the operator T
majorizes all closed range elements of the spectral radius algebra of T, when T
is a weighted condi- tional expectation operator on L2(F) or a rank one
operator on the arbitrary Hilbert space H.


title:
$K \to \pi$ semileptonic form factors with $N_f=2+1+1$ Twisted Mass
  fermions

abstract:
  We present a lattice QCD determination of the vector and scalar form factors
of the semileptonic $K \to \pi \ell \nu$ decay which are relevant for the
extraction of the CKM matrix element $|V_{us}|$ from experimental data. Our
results are based on the gauge configurations produced by the European Twisted
Mass Collaboration with $N_f = 2+1+1$ dynamical fermions, which include in the
sea, besides two light mass degenerate quarks, also the strange and the charm
quarks. We use data simulated at three different values of the lattice spacing
and with pion masses as small as $210$ MeV. Our final result for the vector
form factor at zero momentum transfer is $f_+(0) = 0.9709 (46)$, where the
uncertainty is both statistical and systematic combined in quadrature. Using
the latest experimental value of $f_+(0) |V_{us}|$ from $K_{\ell 3}$ decays, we
obtain $|V_{us}| = 0.2230 (11)$, which allows to test the unitarity constraint
of the Standard Model below the permille level once the determination of
$|V_{ud}|$ from superallowed nuclear $\beta$ decays is adopted. A slight
tension with unitarity at the level of $\sim 2$ standard deviations is
observed. Moreover we present our results for the semileptonic scalar
$f_0(q^2)$ and vector $f_+(q^2)$ form factors in the whole range of values of
the squared four-momentum transfer $q^2$ measured in $K_{\ell 3}$ decays,
obtaining a very good agreement with the momentum dependence of the
experimental data. We provide a set of synthetic data points representing our
results for the vector and scalar form factors at the physical point for
several selected values of $q^2$.


title:
Frequency-dependent polarization-angle-phase-shift in the
  microwave-induced magnetoresistance oscillations

abstract:
  Linear polarization angle, $\theta$, dependent measurements of the microwave
radiation-induced oscillatory magnetoresistance, $R_{xx}$, in high mobility
GaAs/AlGaAs 2D electron devices have shown a $\theta$ dependence in the
oscillatory amplitude along with magnetic field, frequency, and
extrema-dependent phase shifts, $\theta_{0}$. Here, we suggest a microwave
frequency dependence of $\theta_{0} (f)$ using an analysis that averages over
other smaller contributions, when those contributions are smaller than
estimates of the experimental uncertainty.


title:
TouchSignatures: Identification of User Touch Actions and PINs Based on
  Mobile Sensor Data via JavaScript

abstract:
  Conforming to W3C specifications, mobile web browsers allow JavaScript code
in a web page to access motion and orientation sensor data without the user's
permission. The associated risks to user security and privacy are however not
considered in W3C specifications. In this work, for the first time, we show how
user security can be compromised using these sensor data via browser, despite
that the data rate is 3 to 5 times slower than what is available in app. We
examine multiple popular browsers on Android and iOS platforms and study their
policies in granting permissions to JavaScript code with respect to access to
motion and orientation sensor data. Based on our observations, we identify
multiple vulnerabilities, and propose TouchSignatures which implements an
attack where malicious JavaScript code on an attack tab listens to such sensor
data measurements. Based on these streams, TouchSignatures is able to
distinguish the user's touch actions (i.e., tap, scroll, hold, and zoom) and
her PINs, allowing a remote website to learn the client-side user activities.
We demonstrate the practicality of this attack by collecting data from real
users and reporting high success rates using our proof-of-concept
implementations. We also present a set of potential solutions to address the
vulnerabilities. The W3C community and major mobile browser vendors including
Mozilla, Google, Apple and Opera have acknowledge our work and are implementing
some of our proposed countermeasures.


title: Higher spin representations of K(E10)

abstract:
  We review the recently constructed non-trivial fermionic representations of
the infinite-dimensional subalgebra K(E10) of the hyperbolic Kac--Moody algebra
E10. These representations are all unfaithful (and more specifically, of finite
dimension). In addition we present their decompositions under the various
finite-dimensional subgroups associated with some maximal supergravities in
dimensions D<=11, and the projectors for `spin-7/2' which have not been given
before. Those representations that have not been derived from supergravity
still have to find a role and a proper physical interpretation in the
conjectured correspondence between E10 and M-theory. Nevertheless, they provide
novel mathematical structures that could shed some light on fundamental
questions in supergravity and on the possible role of K(E10) as an `R-symmetry'
of M-theory, and perhaps also on the algebra E10 itself.


title:
Non-asymptotic Confidence Sets for Extrinsic Means on Spheres and
  Projective Spaces

abstract:
  Confidence sets from i.i.d. data are constructed for the extrinsic mean of a
probabilty measure P on spheres, real projective spaces, and complex projective
spaces, as well as Grassmann manifolds, with the latter three embedded by the
Veronese-Whitney embedding. When the data are sufficiently concentrated, these
are projections of a ball around the corresponding Euclidean sample mean.
Furthermore, these confidence sets are rate-optimal. The usefulness of this
approach is illustrated for projective shape data.


title: An exploratory study of heavy domain wall fermions on the lattice

abstract:
  We report on an exploratory study of domain wall fermions (DWF) as a lattice
regularisation for heavy quarks. Within the framework of quenched QCD with the
tree-level improved Symanzik gauge action we identify the DWF parameters which
minimise discretisation effects. We find the corresponding effective 4$d$
overlap operator to be exponentially local, independent of the quark mass. We
determine a maximum bare heavy quark mass of $am_h\approx 0.4$, below which the
approximate chiral symmetry and O(a)-improvement of DWF are sustained. This
threshold appears to be largely independent of the lattice spacing. Based on
these findings, we carried out a detailed scaling study for the heavy-strange
meson dispersion relation and decay constant on four ensembles with lattice
spacings in the range $2.0-5.7\,\mathrm{GeV}$. We observe very mild $a^2$
scaling towards the continuum limit. Our findings establish a sound basis for
heavy DWF in dynamical simulations of lattice QCD with relevance to Standard
Model phenomenology.


title:
Optimal performance of periodically driven, stochastic heat engines
  under limited control

abstract:
  We consider the performance of periodically driven stochastic heat engines in
the linear response regime. Reaching the theoretical bounds for efficiency and
efficiency at maximum power typically requires full control over the design and
the driving of the system. We develop a framework which allows to quantify the
role that limited control over the system has on the performance. Specifically,
we show that optimizing the driving entering the work extraction for a given
temperature protocol leads to a universal, one-parameter dependence for both
maximum efficiency and maximum power as a function of efficiency. In
particular, we show that reaching Carnot efficiency (and, hence, Curzon-Ahlborn
efficiency at maximum power) requires to have control over the amplitude of the
full Hamiltonian of the system. Since the kinetic energy cannot be controlled
by an external parameter, heat engines based on underdamped dynamics can
typically not reach Carnot efficiency. We illustrate our general theory with a
paradigmatic case study of a heat engine consisting of an underdamped charged
particle in a modulated two-dimensional harmonic trap in the presence of a
magnetic field.


title: INFN What Next: Ultra-relativistic Heavy-Ion Collisions

abstract:
  This document was prepared by the community that is active in Italy, within
INFN (Istituto Nazionale di Fisica Nucleare), in the field of
ultra-relativistic heavy-ion collisions. The experimental study of the phase
diagram of strongly-interacting matter and of the Quark-Gluon Plasma (QGP)
deconfined state will proceed, in the next 10-15 years, along two directions:
the high-energy regime at RHIC and at the LHC, and the low-energy regime at
FAIR, NICA, SPS and RHIC. The Italian community is strongly involved in the
present and future programme of the ALICE experiment, the upgrade of which will
open, in the 2020s, a new phase of high-precision characterisation of the QGP
properties at the LHC. As a complement of this main activity, there is a
growing interest in a possible future experiment at the SPS, which would target
the search for the onset of deconfinement using dimuon measurements. On a
longer timescale, the community looks with interest at the ongoing studies and
discussions on a possible fixed-target programme using the LHC ion beams and on
the Future Circular Collider.


title:
Justification of the Coupled Mode Asymptotics for Localized Wavepackets
  in the Periodic Nonlinear Schr\"odinger Equation

abstract:
  We consider wavepackets composed of two modulated carrier Bloch waves with
opposite group velocities in the one dimensional periodic Nonlinear
Schroedinger/Gross-Pitaevskii equation. These can be approximated by first
order coupled mode equations (CMEs) for the two slowly varying envelopes. Under
a suitably selected periodic perturbation of the periodic structure the CMEs
possess a spectral gap of the corresponding spatial operator and allow families
of exponentially localized solitary waves parametrized by velocity. This leads
to a family of approximate solitary waves in the periodic nonlinear
Schroedinger equation. Besides a formal derivation of the CMEs a rigorous
justification of the approximation and an error estimate in the supremum norm
are provided. Several numerical tests corroborate the analysis.