title:
Probing new physics in diphoton production with proton tagging at the
  Large Hadron Collider

abstract:
  The sensitivities to anomalous quartic photon couplings at the Large Hadron
Collider are estimated using diphoton production via photon fusion. The tagging
of the protons proves to be a very powerful tool to suppress the background and
unprecedented sensitivities down to $6 \cdot 10^{-15}$\gev$^{-4}$ are obtained,
providing a new window on extra dimensions and strongly-interacting composite
states in the multi-TeV range. Generic contributions to quartic photon
couplings from charged and neutral particles with arbitrary spin are also
presented.


title:
Using correlations between CMB lensing and large-scale structure to
  measure primordial non-Gaussianity

abstract:
  We apply a new method to measure primordial non-Gaussianity, using the
cross-correlation between galaxy surveys and the CMB lensing signal to measure
galaxy bias on very large scales, where local-type primordial non-Gaussianity
predicts a $k^2$ divergence. We use the CMB lensing map recently published by
the Planck collaboration, and measure its external correlations with a suite of
six galaxy catalogues spanning a broad redshift range. We then consistently
combine correlation functions to extend the recent analysis by Giannantonio et
al. (2013), where the density-density and the density-CMB temperature
correlations were used. Due to the intrinsic noise of the Planck lensing map,
which affects the largest scales most severely, we find that the constraints on
the galaxy bias are similar to the constraints from density-CMB temperature
correlations. Including lensing constraints only improves the previous
statistical measurement errors marginally, and we obtain $ f_{\mathrm{NL}} = 12
\pm 21 $ (1$\sigma$) from the combined data set. However, the lensing
measurements serve as an excellent test of systematic errors: we now have three
methods to measure the large-scale, scale-dependent bias from a galaxy survey:
auto-correlation, and cross-correlation with both CMB temperature and lensing.
As the publicly available Planck lensing maps have had their largest-scale
modes at multipoles $l<10$ removed, which are the most sensitive to the
scale-dependent bias, we consider mock CMB lensing data covering all
multipoles. We find that, while the effect of $f_{\mathrm{NL}}$ indeed
increases significantly on the largest scales, so do the contributions of both
cosmic variance and the intrinsic lensing noise, so that the improvement is
small.


title:
On the Effectiveness of Polynomial Realization of Reed-Solomon Codes for
  Storage Systems

abstract:
  There are different ways to realize Reed Solomon (RS) codes. While in the
storage community, using the generator matrices to implement RS codes is more
popular, in the coding theory community the generator polynomials are typically
used to realize RS codes. Prominent exceptions include HDFS-RAID, which uses
generator polynomial based erasure codes, and extends the Apache Hadoop's file
system.
  In this paper we evaluate the performance of an implementation of polynomial
realization of Reed-Solomon codes, along with our optimized version of it,
against that of a widely-used library (Jerasure) that implements the main
matrix realization alternatives. Our experimental study shows that despite
significant performance gains yielded by our optimizations, the polynomial
implementations' performance is constantly inferior to those of matrix
realization alternatives in general, and that of Cauchy bit matrices in
particular.


title:
Partial regularity and smooth topology-preserving approximations of
  rough domains

abstract:
  For a bounded domain $\Omega\subset\mathbb{R}^m, m\geq 2,$ of class $C^0$,
the properties are studied of fields of `good directions', that is the
directions with respect to which $\partial\Omega$ can be locally represented as
the graph of a continuous function. For any such domain there is a canonical
smooth field of good directions defined in a suitable neighbourhood of
$\partial\Omega$, in terms of which a corresponding flow can be defined. Using
this flow it is shown that $\Omega$ can be approximated from the inside and the
outside by diffeomorphic domains of class $C^\infty$. Whether or not the image
of a general continuous field of good directions (pseudonormals) defined on
$\partial\Omega$ is the whole of $\mathbb{S}^{m-1}$ is shown to depend on the
topology of $\Omega$. These considerations are used to prove that if $m=2,3$,
or if $\Omega$ has nonzero Euler characteristic, there is a point
$P\in\partial\Omega$ in the neighbourhood of which $\partial\Omega$ is
Lipschitz. The results provide new information even for more regular domains,
with Lipschitz or smooth boundaries.


title:
Finite Field-Energy and Interparticle Potential in Logarithmic
  Electrodynamics

abstract:
  We pursue an investigation of Logarithmic Electrodynamics, for which the
field-energy of a point-like charge is finite, as it happens in the case of the
usual Born-Infeld electrodynamics. We also show that, contrary to the latter,
Logarithmic Electrodynamics exhibits the feature of birefringence. Next, we
analyze the lowest-order modifications for both Logarithmic Electrodynamics and
for its non-commutative version, within the framework of the gauge-invariant
path-dependent variables formalism. The calculation shows a long-range
correction ($1/r^5$- type) to the Coulomb potential for Logarithmic
Electrodynamics. Interestingly enough, for its non-commutative version, the
interaction energy is ultraviolet finite. We highlight the role played by the
new quantum of length in our analysis.


title:
Universality of Jamming Criticality in Overdamped Shear-Driven
  Frictionless Disks

abstract:
  We investigate the criticality of the jamming transition for overdamped
shear-driven frictionless disks in two dimensions for two different models of
energy dissipation: (i) Durian's bubble model with dissipation proportional to
the velocity difference of particles in contact, and (ii) Durian's "mean-field"
approximation to (i), with dissipation due to the velocity difference between
the particle and the average uniform shear flow velocity. By considering
velocity correlations, finite-size behavior of pressure, and the pressure
analog of viscosity, we argue that these two models share the same critical
behavior.


title:
Spin-Orbit Qubit on a Multiferroic Insulator in a Superconducting
  Resonator

abstract:
  We propose a spin-orbit qubit in a nanowire quantum dot on the surface of a
multiferroic insulator with a cycloidal spiral magnetic order. The spiral
exchange field from the multiferroic insulator causes an inhomogeneous
Zeeman-like interaction on the electron spin in the quantum dot, producing a
spin-orbit qubit. The absence of an external magnetic field benefits the
integration of such spin-orbit qubit into high-quality superconducting
resonators. By exploiting the Rashba spin-orbit coupling in the quantum dot via
a gate voltage, one can obtain an effective spin-photon coupling with an
efficient on/off switching. This makes the proposed device controllable and
promising for hybrid quantum communications.


title: Numbers as functions

abstract:
  In this survey I discuss A. Buium's theory of ``differential equations in the
p-adic direction'' ([Bu05]) and its interrelations with ``geometry over fields
with one element'', on the background of various approaches to p-adic models in
theoretical physics.


title: Topological susceptibility from the twisted mass Dirac operator spectrum

abstract:
  We present results of our computation of the topological susceptibility with
$N_f=2$ and $N_f=2+1+1$ flavours of maximally twisted mass fermions, using the
method of spectral projectors. We perform a detailed study of the quark mass
dependence and discretization effects. We make an attempt to confront our data
with chiral perturbation theory and extract the chiral condensate from the
quark mass dependence of the topological susceptibility. We compare the value
with the results of our direct computation from the slope of the mode number.
We emphasize the role of autocorrelations and the necessity of long Monte Carlo
runs to obtain results with good precision. We also show our results for the
spectral projector computation of the ratio of renormalization constants
$Z_P/Z_S$.


title:
Sistem pendukung keputusan kelayakan TKI ke luar negeri menggunakan
  FMADM

abstract:
  BP3TKI Palembang is the government agencies that coordinate, execute and
selection of prospective migrants registration and placement. To simplify the
existing procedures and improve decision-making is necessary to build a
decision support system (DSS) to determine eligibility for employment abroad by
applying Fuzzy Multiple Attribute Decision Making (FMADM), using the linear
sequential systems development methods. The system is built using Microsoft
Visual Basic. Net 2010 and SQL Server 2008 database. The design of the system
using use case diagrams and class diagrams to identify the needs of users and
systems as well as systems implementation guidelines. This Decision Support
System able to rank and produce the prospective migrants, making it easier for
parties to take decision BP3TKI the workers who will be working out of the
country.


title:
The atmospheric chemistry of the warm Neptune GJ 3470b: influence of
  metallicity and temperature on the CH4/CO ratio

abstract:
  Current observation techniques are able to probe the atmosphere of some giant
exoplanets and get some clues about their atmospheric composition. However, the
chemical compositions derived from observations are not fully understood, as
for instance in the case of the CH4/CO abundance ratio, which is often inferred
different from what has been predicted by chemical models. Recently, the warm
Neptune GJ3470b has been discovered and because of its close distance from us
and high transit depth, it is a very promising candidate for follow up
characterisation of its atmosphere. We study the atmospheric composition of
GJ3470b in order to compare with the current observations of this planet, to
prepare the future ones, but also as a typical case study to understand the
chemical composition of warm (sub-)Neptunes. The metallicity of such
atmospheres is totally uncertain, and vary probably to values up to 100x solar.
We explore the space of unknown parameters to predict the range of possible
atmospheric compositions. Within the parameter space explored we find that in
most cases methane is the major carbon-bearing species. We however find that in
some cases, typically for high metallicities with a sufficiently high
temperature the CH4/CO abundance ratio can become lower than unity, as
suggested by some multiwavelength photometric observations of other warm
(sub-)Neptunes, such as GJ1214b and GJ436b. As for the emission spectrum of
GJ3470b, brightness temperatures at infrared wavelengths may vary between 400
and 800K depending on the thermal profile and metallicity. Combined with a hot
temperature profile, a substantial enrichment in heavy elements by a factor of
100 with respect to the solar composition can shift the carbon balance in
favour of carbon monoxide at the expense of CH4. Nevertheless, current
observations of this planet do not allow yet to determine which model is more
accurate.


title: Multi-layer Ti-based Coating Obtained by Arc PVD Method

abstract:
  We report the obtaining and primary studies of ~ 250microns thick multi-layer
Ti-based protective coating deposited at high cooling rate from substance
generated by cathode arc discharge in vacuum. High adhesion to steel substrate
was attained through prior Arc plasma generator cleaning and successive Ion
Bombardment method. All three arc-generated fractions including mainly droplet,
vapour and ions have been utilised to form the coating. Obtained coating
features pore-free, least defects and high hardness which, besides N presence,
supposed to result from mainly martensitic transformations occurred at the
presence of Nitrogen. Two intermediate thin layers of Cu of few microns were
achieved to insert within coating presumably to reduce overall elastic modulus
of the material.


title: Time-dependent CP violation in $B$ decays at Belle

abstract:
  Using the full data sample collected with the Belle detector at the KEKB
asymmetric-energy $e^+e^-$ collider, we present three recent measurements of
time-dependent CP violation in $B$ decays, and a measurement of branching
fraction of the $B^0\to\rho^0\rho^0$ decay. We studied $B\to\omega K$ decays
and measured the values of CP violation parameters in $B^0\to\omega K^0_S$ to
be $A_{\omega K^0_S} =-0.36\pm 0.19(stat)\pm 0.05(syst)$ and $S_{\omega K^0_S}=
+0.91\pm 0.32 \pm 0.05 $, which gives the first evidence of CP violation in
this decay. In addition, we measured the direct CP violation in $B^+\to\omega
K^+$ to be $A_{CP} (B^+ \to \omega K^+)=-0.03\pm 0.04 \pm 0.01$, and two
branching fractions $B(B^0 \to \omega K^0)=(4.5\pm 0.4\pm 0.3) \times 10^{-6}$
and $B(B^+ \to \omega K^+)=(6.8\pm 0.4 \pm 0.4) \times 10^{-6}$ (preliminary).
From the measurement of CP violation parameters in the $B^0\to\eta'K^0$ decay
we obtain $S_{\eta'K^0} = 0.68 \pm 0.07\pm 0.03$ and $A_{\eta'K^0} = +0.03 \pm
0.05\pm 0.04$ (preliminary), which are the world's most precise values to date.
Measuring CP violating parameters in the $B^0\to\pi^+\pi^-$ decay gives
$A_{\pi^+\pi^-} = +0.33\pm 0.06\pm 0.03$ and $S_{\pi^+\pi^-} = -0.64\pm 0.08\pm
0.03$. This result is used in an isospin analysis to constrain the $\phi_2$
angle of the unitarity triangle, with which we rule out the region $23.8^\circ
< \phi_2 < 66.8^\circ$ at the $1\sigma$ confidence level. The measured
branching fraction of the $B^0\to\rho^0\rho^0$ decay is $B(B^0\to\rho^0\rho^0)
= (1.02\pm 0.30\pm 0.15)\times 10^{-6}$, with the fraction of longitudinally
polarized $\rho^0$ mesons being $f_L = 0.21^{+0.18}_{-0.22}\pm 0.13$. We obtain
also the first evidence of the $B^0\to f_0\rho^0$ decay, by measuring $B(B^0\to
f_0 \rho^0)\times B(f_0\to \pi^+\pi^-) = (0.86\pm 0.27 \pm 0.14)\times
10^{-6}$.


title:
Collisionless Reconnection in the Large Guide Field Regime: Gyrokinetic
  Versus Particle-in-Cell Simulations

abstract:
  Results of the first validation of large guide field, $B_g / \delta B_0 \gg
1$, gyrokinetic simulations of magnetic reconnection at a fusion and solar
corona relevant $\beta_i = 0.01$ and solar wind relevant $\beta_i = 1$ are
presented, where $\delta B_0$ is the reconnecting field. Particle-in-cell (PIC)
simulations scan a wide range of guide magnetic field strength to test for
convergence to the gyrokinetic limit. The gyrokinetic simulations display a
high degree of morphological symmetry, to which the PIC simulations converge
when $\beta_i B_g / \delta B_0 \gtrsim 1$ and $B_g / \delta B_0 \gg 1$. In the
regime of convergence, the reconnection rate, relative energy conversion, and
overall magnitudes are found to match well between the PIC and gyrokinetic
simulations, implying that gyrokinetics is capable of making accurate
predictions well outside its regime of formal applicability. These results
imply that in the large guide field limit many quantities resulting from the
nonlinear evolution of reconnection scale linearly with the guide field.


title:
Kinetic Turbulence in the Terrestrial Magnetosheath: Cluster
  Observations

abstract:
  We present a first statistical study of subproton and electron scales
turbulence in the terrestrial magnetosheath using the Cluster Search Coil
Magnetometer (SCM) waveforms of the STAFF instrument measured in the frequency
range [1,180] Hz. It is found that clear spectral breaks exist near the
electron scale, which separate two power-law like frequency bands referred to
as the dispersive and the electron dissipation ranges. The frequencies of the
breaks f_b are shown to be well correlated with the electron gyroscale \rho_e
rather than with the electron inertial length de. The distribution of the
slopes below fb was found to be narrow and peaks near -2.9, while that of the
slopes above fb was found broader, peaks near -5.2 and has values as low as
-7.5. This is the first time that such steep power-law spectra are reported in
space plasma turbulence. These observations provide strong constraints on
theoretical modeling of kinetic turbulence and dissipation in collisionless
magnetized plasmas.


title:
Relating maximum entropy, resilient behavior and game-theoretic
  equilibrium feedback operators in multi-channel systems

abstract:
  In this paper, we first draw a connection between the existence of a
stationary density function (which corresponds to an equilibrium state in the
sense of statistical mechanics) and a set of feedback operators in a
multi-channel system that strategically interacts in a game-theoretic
framework. In particular, we show that there exists a set of (game-theoretic)
equilibrium feedback operators such that the composition of the multi-channel
system with this set of equilibrium feedback operators, when described by
density functions, will evolve towards an equilibrium state in such a way that
the entropy of the whole system is maximized. As a result of this, we are led
to study, by a means of a stationary density function (i.e., a common
fixed-point) for a family of Frobenius-Perron operators, how the dynamics of
the system together with the equilibrium feedback operators determine the
evolution of the density functions, and how this information translates into
the maximum entropy behavior of the system. Later, we use such results to
examine the resilient behavior of this set of equilibrium feedback operators,
when there is a small random perturbation in the system.


title: Decomposition and Gluing for Adiabatic Quantum Optimization

abstract:
  Farhi and others have introduced the notion of solving NP problems using
adiabatic quantum com- puters. We discuss an application of this idea to the
problem of integer factorization, together with a technique we call gluing
which can be used to build adiabatic models of interesting problems. Although
adiabatic quantum computers already exist, they are likely to be too small to
directly tackle problems of interesting practical sizes for the foreseeable
future. Therefore, we discuss techniques for decomposition of large problems,
which permits us to fully exploit such hardware as may be available. Numerical
re- sults suggest that even simple decomposition techniques may yield
acceptable results with subexponential overhead, independent of the performance
of the underlying device.


title:
Tuning of polarisation sensitivity in closely-stacked trilayer InAs/GaAs
  quantum dots induced by overgrowth dynamics

abstract:
  Tailoring electronic and optical properties of self-assembled InAs quantum
dots (QDs) is a critical limit for the design of several QD-based
optoelectronic devices operating in the telecom frequency range. We describe
how a fine control of the strain-induced surface kinetics during the growth of
vertically-stacked multiple layers of QDs allow to engineer their self
organization process. Most noticeably, the present study shows that the
underlying strain field induced along a QD stack can be modulated and
controlled by time-dependent intermixing and segregation effects occurring
after capping with GaAs spacer. This leads to a drastic increase of TM/TE
polarization ratio of emitted light, not accessible from the conventional
growth parameters. Our detailed experimental measurements supported by
comprehensive multi-million atom simulations of strain, electronic, and optical
properties, provide in-depth analysis of the grown QD samples leading us to
depict a clear picture on atomic scale phenomena affecting the proposed growth
dynamics and consequent QD polarization response.


title: On curves with nonnegative torsion

abstract:
  We provide new results and new proofs of results about the torsion of curves
in $\mathbb{R}^3$. Let $\gamma$ be a smooth curve in $\mathbb{R}^3$ that is the
graph over a simple closed curve in $\mathbb{R}^2$ with positive curvature. We
give a new proof that if $\gamma$ has nonnegative (or nonpositive) torsion,
then $\gamma$ has zero torsion and hence lies in a plane. Additionally, we
prove the new result that a simple closed plane curve, without any assumption
on its curvature, cannot be perturbed to a closed space curve of constant
nonzero torsion. We also prove similar statements for curves in Lorentzian
$\mathbb{R}^{2,1}$ which are related to important open questions about time
flat surfaces in spacetimes and mass in general relativity.


title:
A Design Blueprint for Virtual Organizations in a Service Oriented
  Landscape

abstract:
  "United we stand, divided we fall" is a well known saying. We are living in
the era of virtual collaborations. Advancement on conceptual and technological
level has enhanced the way people communicate. Everything-as-a-Service once a
dream, now becoming a reality.
  Problem nature has also been changed over the time. Today, e-Collaborations
are applied to all the domains possible. Extensive data and computing resources
are in need and assistance from human experts is also becoming essential. This
puts a great responsibility on Information Technology (IT) researchers and
developers to provide generic platforms where user can easily communicate and
solve their problems. To realize this concept, distributed computing has
offered many paradigms, e.g. cluster, grid, cloud computing. Virtual
Organization (VO) is a logical orchestration of globally dispersed resources to
achieve common goals.
  Existing paradigms and technology are used to form Virtual Organization, but
lack of standards remained a critical issue for last two decades. Our research
endeavor focuses on developing a design blueprint for Virtual Organization
building process. The proposed standardization process is a two phase activity.
First phase provides requirement analysis and the second phase presents a
Reference Architecture for Virtual Organization (RAVO). This form of
standardization is chosen to accommodate both technological and paradigm shift.
We categorize our efforts in two parts. First part consists of a pattern to
identify the requirements and components of a Virtual Organization. Second part
details a generic framework based on the concept of Everything-as-a-Service.


title:
New Repair strategy of Hadamard Minimum Storage Regenerating Code for
  Distributed Storage System

abstract:
  The newly presented $(k+2,k)$ Hadamard minimum storage regenerating (MSR)
code is the first class of high rate storage code with optimal repair property
for all single node failures. In this paper, we propose a new simple repair
strategy, which can considerably reduces the computation load of the node
repair in contrast to the original one.


title: Temperature Dependence of the Casimir Force

abstract:
  The Casimir force - at first a rather unexpected consequence of quantum
electrodynamics - was discovered by Hendrik Casimir in Eindhoven in 1948. It
predicts that two uncharged metal plates experience an attractive force because
of the zero-point fluctuations of the electromagnetic field. The idea was
tested experimentally in the 1950's and 1960's, but the results were not so
accurate that one could make a definite conclusion regarding the existence of
the effect. Evgeny Lifshitz expanded the theory in 1955 so as to deal with
general dielectric media. Much experimental work has later been done to test
the theory's predictions, especially with regards to the temperature dependence
of the effect. The existence of the effect itself was verified beyond doubt by
Sabisky and Anderson in 1973. Another quarter century had to pass before
Lamoreaux and collaborators were able to confirm - or at least make plausible -
the temperature dependence predicted by Lifshitz formula in combination with
reasonable input data for the material's dispersive properties. The situation
is not yet clear-cut, however; there are recent experiments indicating results
in disagreement with those of Lamoreaux. In the present paper a brief review is
given of the status of this research field.


title:
Computer-verification of the structure of some classes of fragile
  matroids

abstract:
  This technical report accompanies the following three papers. It contains the
computations necessary to verify some of the results claimed in those papers.
  [1] Carolyn Chun, Deborah Chun, Dillon Mayhew, and Stefan H. M. van Zwam.
Fan-extensions in fragile matroids. In preparation. [2] Carolyn Chun, Dillon
Mayhew, Geoff Whittle, and Stefan H. M. van Zwam. The structure of binary
Fano-fragile matroids. In preparation. [3] Ben Clark, Dillon Mayhew, Geoff
Whittle, and Stefan H. M. van Zwam. The structure of {U2,5, U3,5}-fragile
matroids. In preparation.


title:
First Indication of Terrestrial Matter Effects on Solar Neutrino
  Oscillation

abstract:
  We report an indication that the elastic scattering rate of solar $^8$B
neutrinos with electrons in the Super-Kamiokande detector is larger when the
neutrinos pass through the Earth during nighttime. We determine the day/night
asymmetry, defined as the difference of the average day rate and average night
rate divided by the average of those two rates, to be
$(-3.2\pm1.1(\text{stat})\pm0.5(\text{syst}))\%$, which deviates from zero by
2.7 $\sigma$. Since the elastic scattering process is mostly sensitive to
electron-flavored solar neutrinos, a non-zero day/night asymmetry implies that
the flavor oscillations of solar neutrinos are affected by the presence of
matter within the neutrinos' flight path. Super-Kamiokande's day/night
asymmetry is consistent with neutrino oscillations for
$4\times10^{-5}$eV$^2\leq\Delta m^2_{21}\leq7\times10^{-5}$eV$^2$ and large
mixing values of $\theta_{12}$, at the $68\%$ C.L.


title: Aharonov-Bohm interferometry with a tunnel-coupled wire

abstract:
  Recent experiments [M. Yamamoto et al., Nature Nanotechnology 7, 247 (2012)]
used the transport of electrons through an Aharonov-Bohm interferometer and two
coupled channels (at both ends of the interferometer) to demonstrate a
manipulable flying qubit. Results included in-phase and anti-phase
Aharonov-Bohm (AB) oscillations of the two outgoing currents as a function of
the magnetic flux, for strong and weak inter-channel coupling, respectively.
Here we present new experimental results for a three terminal interferometer,
with a tunnel coupling between the two outgoing wires. We show that in some
limits, this system is an even simpler realization of the "two-slit"
experiment. We also present a simple tight- binding theoretical model which
imitates the experimental setup. For weak inter-channel coupling, the AB
oscillations in the current which is reflected from the device are very small,
and therefore the oscillations in the two outgoing currents must cancel each
other, yielding the anti-phase behavior, independent of the length of the
coupling regime. For strong inter-channel coupling, whose range depends on the
asymmetry between the channels, and for a relatively long coupling distance,
all except two of the waves in the coupled channels become evanescent. For the
remaining running waves one has a very weak dependence of the ratio between the
currents in the two channels on the magnetic flux, implying that these currents
are in phase with each other.


title: Potential of LOFT telescope for the search of dark matter

abstract:
  Large Observatory For X-ray Timing (LOFT) is a next generation X-ray
telescope selected by European Space Agency as one of the space mission
concepts within the ``Cosmic Vision'' programme. The Large Area Detector on
board of LOFT will be a collimator-type telescope with an unprecedentedly large
collecting area of about 10 square meters in the energy band between 2 and 100
keV. We demonstrate that LOFT will be a powerful dark matter detector, suitable
for the search of the X-ray line emission expected from decays of light dark
matter particles in galactic halos. We show that LOFT will have sensitivity for
dark matter line search more than an order of magnitude higher than that of all
existing X-ray telescopes. In this way, LOFT will be able to provide a new
insight into the fundamental problem of the nature of dark matter.


title: The Total Variation on Hypergraphs - Learning on Hypergraphs Revisited

abstract:
  Hypergraphs allow one to encode higher-order relationships in data and are
thus a very flexible modeling tool. Current learning methods are either based
on approximations of the hypergraphs via graphs or on tensor methods which are
only applicable under special conditions. In this paper, we present a new
learning framework on hypergraphs which fully uses the hypergraph structure.
The key element is a family of regularization functionals based on the total
variation on hypergraphs.


title: Maximal induced matchings in triangle-free graphs

abstract:
  An induced matching in a graph is a set of edges whose endpoints induce a
$1$-regular subgraph. It is known that any $n$-vertex graph has at most
$10^{n/5} \approx 1.5849^n$ maximal induced matchings, and this bound is best
possible. We prove that any $n$-vertex triangle-free graph has at most $3^{n/3}
\approx 1.4423^n$ maximal induced matchings, and this bound is attained by any
disjoint union of copies of the complete bipartite graph $K_{3,3}$. Our result
implies that all maximal induced matchings in an $n$-vertex triangle-free graph
can be listed in time $O(1.4423^n)$, yielding the fastest known algorithm for
finding a maximum induced matching in a triangle-free graph.


title: Ferroelectricity at ferroelectric domain walls

abstract:
  We present a first-principles study of model domain walls (DWs) in prototypic
ferroelectric PbTiO3. At high temperature the DW structure is somewhat trivial,
with atoms occupying high- symmetry positions. However, upon cooling the DW
undergoes a symmetry-breaking transition characterized by a giant dielectric
anomaly and the onset of a large and switchable polarization. Our results thus
corroborate previous arguments for the occurrence of ferroic orders at
structural DWs, providing a detailed atomistic picture of a temperature-driven
DW-confined transformation. Beyond its relevance to the field of
ferroelectrics, our results highlight the interest of these DWs in the broader
areas of low-dimensional physics and phase transitions in strongly-fluctuating
systems.


title:
Perturbative Field-Theoretical Renormalization Group Approach to
  Driven-Dissipative Bose-Einstein Criticality

abstract:
  The universal critical behavior of the driven-dissipative non-equilibrium
Bose-Einstein condensation transition is investigated employing the
field-theoretical renormalization group method. Such criticality may be
realized in broad ranges of driven open systems on the interface of quantum
optics and many-body physics, from exciton-polariton condensates to cold atomic
gases. The starting point is a noisy and dissipative Gross-Pitaevski equation
corresponding to a complex valued Landau-Ginzburg functional, which captures
the near critical non-equilibrium dynamics, and generalizes Model A for
classical relaxational dynamics with non-conserved order parameter. We confirm
and further develop the physical picture previously established by means of a
functional renormalization group study of this system. Complementing this
earlier numerical analysis, we analytically compute the static and dynamical
critical exponents at the condensation transition to lowest non-trivial order
in the dimensional epsilon expansion about the upper critical dimension d_c =
4, and establish the emergence of a novel universal scaling exponent associated
with the non-equilibrium drive. We also discuss the corresponding situation for
a conserved order parameter field, i.e., (sub-)diffusive Model B with complex
coefficients.


title: The particle content of low-power radio galaxies in groups and clusters

abstract:
  The synchrotron-radiating particles and magnetic fields in low-power radio
galaxies (including most nearby cluster-centre sources), if at equipartition,
can provide only a small fraction of the total internal energy density of the
radio lobes or plumes, which is now well constrained via X-ray observations of
their external environments. We consider the constraints on models for the
dominant energy contribution in low-power radio-galaxy lobes obtained from a
detailed comparison of how the internal equipartition pressure and external
pressure measured from X-ray observations evolve with distance for two radio
galaxies, 3C 31 and Hydra A. We rule out relativistic-lepton dominance of the
radio lobes, and conclude that models in which magnetic field or relativistic
protons/ions carried up the jet dominate lobe energetics are unlikely. Finally,
we argue that entrainment of material from the jet surroundings can provide the
necessary pressure, and construct a simple self-consistent model of the
evolution of the entrainment rate required for pressure balance along the
100-kpc scale plumes of 3C 31. Such a model requires that the entrained
material is heated to temperatures substantially above that of the surrounding
intra-group or cluster medium, and that the temperature of the thermal
component of the jet increases with distance, though remaining
sub-relativistic.


title:
Phase topology of one system with separated variables and singularities
  of the symplectic structure

abstract:
  We consider an example of a system with two degrees of freedom admitting
separation of variables but having a subset of codimension 1 on which the
2-form defining the symplectic structure degenerates. We show how to use
separation of variables to calculate the exact topological invariant of
non-degenerate singularities and singularities appearing due to the symplectic
structure degeneration. New types of non-orientable 3-atoms are found.


title:
An exponential integrator scheme for time discretization of nonlinear
  stochastic wave equation

abstract:
  This work is devoted to convergence analysis of an exponential integrator
scheme for semi-discretization in time of nonlinear stochastic wave equation. A
unified framework is first set forth, which covers important cases of additive
and multiplicative noises. Within this framework, the proposed scheme is shown
to converge uniformly in the strong $L^p$-sense with precise convergence rates
given. The abstract results are then applied to several concrete examples.
Further, weak convergence rates of the scheme are examined for the case of
additive noise. To analyze the weak error for the nonlinear case, techniques
based on the Malliavin calculus were usually exploited in the literature. Under
certain appropriate assumptions on the nonlinearity, this paper provides a weak
error analysis, which does not rely on the Malliavin calculus. The rates of
weak convergence can, as expected, be improved in comparison with the strong
rates. Both strong and weak convergence results obtained here show that the
proposed method achieves higher convergence rates than the implicit Euler and
Crank-Nicolson time discretizations. Numerical results are finally reported to
confirm our theoretical findings.


title: Compressive sampling and dynamic mode decomposition

abstract:
  This work develops compressive sampling strategies for computing the dynamic
mode decomposition (DMD) from heavily subsampled or output-projected data. The
resulting DMD eigenvalues are equal to DMD eigenvalues from the full-state
data. It is then possible to reconstruct full-state DMD eigenvectors using
$\ell_1$-minimization or greedy algorithms. If full-state snapshots are
available, it may be computationally beneficial to compress the data, compute a
compressed DMD, and then reconstruct full-state modes by applying the projected
DMD transforms to full-state snapshots.
  These results rely on a number of theoretical advances. First, we establish
connections between the full-state and projected DMD. Next, we demonstrate the
invariance of the DMD algorithm to left and right unitary transformations. When
data and modes are sparse in some transform basis, we show a similar invariance
of DMD to measurement matrices that satisfy the so-called restricted isometry
principle from compressive sampling. We demonstrate the success of this
architecture on two model systems. In the first example, we construct a spatial
signal from a sparse vector of Fourier coefficients with a linear dynamical
system driving the coefficients. In the second example, we consider the double
gyre flow field, which is a model for chaotic mixing in the ocean.


title:
Globular clusters and supermassive black holes in galaxies: further
  analysis and a larger sample

abstract:
  We explore several correlations between various large-scale galaxy
properties, particularly total globular cluster population (N_GCS), the central
black hole mass (M_BH), velocity dispersion (nominally sigma_e), and bulge mass
(M_dyn). Our data sample of 49 galaxies, for which both N_GC and M_BH are
known, is larger than used in previous discussions of these two parameters and
we employ the same sample to explore all pairs of correlations. Further, within
this galaxy sample we investigate the scatter in each quantity, with emphasis
on the range of published values for sigma_e and effective radius (R_e). We
find that these two quantities in particular are difficult to measure
consistently and caution that precise intercomparison of galaxy properties
involving R_e and sigma_e is particularly difficult.
  Using both chi^2 and Monte Carlo Markov Chain (MCMC) fitting techniques, we
show that quoted observational uncertainties for all parameters are too small
to represent the true scatter in the data. We find that the correlation between
M_dyn and N_GC is stronger than either the M_BH-sigma_e or M_BH-N_GC relations.
We suggest that this is because both the galaxy bulge population ans N_GC were
fundamentally established at an early epoch during the same series of
star-forming events. By contrast, although the seed for M_BH was likely formed
at a similar epoch, its growth over time is less similar from galaxy to galaxy
and thus less predictable.


title:
Non-Abelian Chern-Simons Actions in Three-dimensional Projective
  Superspaces

abstract:
  We construct an action for the superconformal Chern-Simons theory with
non-Abelian gauge groups in three-dimensional N=3 projective superspace. We
propose a Lagrangian given by the product of the function of the tropical
multiplet, that represents the N=3 vector multiplet, and the O(-1,1) multiplet.
We show how the tropical multiplet is embedded into the O(-1,1) multiplet by
comparing our Lagrangian with the Chern- Simons Lagrangian in the N=2
superspace. We also discuss N=4 generalization of the action.


title:
A finite difference method for a two-point boundary value problem with a
  Caputo fractional derivative

abstract:
  A two-point boundary value problem whose highest-order term is a Caputo
fractional derivative of order $\delta \in (1,2)$ is considered. Al-Refai's
comparison principle is improved and modified to fit our problem. Sharp a
priori bounds on derivatives of the solution $u$ of the boundary value problem
are established, showing that $u''(x)$ may be unbounded at the interval
endpoint $x=0$. These bounds and a discrete comparison principle are used to
prove pointwise convergence of a finite difference method for the problem,
where the convective term is discretized using simple upwinding to yield
stability on coarse meshes for all values of $\delta$. Numerical results are
presented to illustrate the performance of the method.


title: Hall Effect Gyrators and Circulators

abstract:
  The electronic circulator, and its close relative the gyrator, are invaluable
tools for noise management and signal routing in the current generation of
low-temperature microwave systems for the implementation of new quantum
technologies. The current implementation of these devices using the Faraday
effect is satisfactory, but requires a bulky structure whose physical dimension
is close to the microwave wavelength employed. The Hall effect is an
alternative non-reciprocal effect that can also be used to produce desired
device functionality. We review earlier efforts to use an ohmically-contacted
four-terminal Hall bar, explaining why this approach leads to unacceptably high
device loss. We find that capacitive coupling to such a Hall conductor has much
greater promise for achieving good circulator and gyrator functionality. We
formulate a classical Ohm-Hall analysis for calculating the properties of such
a device, and show how this classical theory simplifies remarkably in the
limiting case of the Hall angle approaching 90 degrees. In this limit we find
that either a four-terminal or a three-terminal capacitive device can give
excellent circulator behavior, with device dimensions far smaller than the a.c.
wavelength. An experiment is proposed to achieve GHz-band gyration in
millimetre (and smaller) scale structures employing either semiconductor
heterostructure or graphene Hall conductors. An inductively coupled scheme for
realising a Hall gyrator is also analysed.


title: Weak perturbations of the p-Laplacian

abstract:
  We consider the p-Laplacian in R^d perturbed by a weakly coupled potential.
We calculate the asymptotic expansions of the lowest eigenvalue of such an
operator in the weak coupling limit separately for p>d and p=d and discuss the
connection with Sobolev interpolation inequalities.


title:
Nonlinear Eigenproblems in Data Analysis - Balanced Graph Cuts and the
  RatioDCA-Prox

abstract:
  It has been recently shown that a large class of balanced graph cuts allows
for an exact relaxation into a nonlinear eigenproblem. We review briefly some
of these results and propose a family of algorithms to compute nonlinear
eigenvectors which encompasses previous work as special cases. We provide a
detailed analysis of the properties and the convergence behavior of these
algorithms and then discuss their application in the area of balanced graph
cuts.


title:
Radiative damping and synchronization in a graphene-based terahertz
  emitter

abstract:
  We investigate the collective electron dynamics in a recently proposed
graphene-based terahertz emitter under the influence of the radiative damping
effect, which is included self-consistently in a molecular dynamics approach.
We show that under appropriate conditions synchronization of the dynamics of
single electrons takes place, leading to a rise of the oscillating component of
the charge current. The synchronization time depends dramatically on the
applied dc electric field and electron scattering rate, and is roughly
inversely proportional to the radiative damping rate that is determined by the
carrier concentration and the geometrical parameters of the device. The
emission spectra in the synchronized state, determined by the oscillating
current component, are analyzed. The effective generation of higher harmonics
for large values of the radiative damping strength is demonstrated.


title:
Theoretical, numerical, and experimental study of a flying qubit
  electronic interferometer

abstract:
  We discuss an electronic interferometer recently measured by Yamamoto et al.
This "flying quantum bit" experiment showed quantum oscillations between
electronic trajectories of two tunnel-coupled wires connected via an
Aharanov-Bohm ring. We present a simple scattering model as well as a numerical
microscopic model to describe this experiment. In addition, we present new
experimental data to which we confront our numerical results. While our
analytical model provides basic concepts for designing the flying qubit device,
we find that our numerical simulations allow to reproduce detailed features of
the transport measurements such as in-phase and anti-phase oscillations of the
two output currents as well as a smooth phase shift when sweeping a side gate.
Furthermore, we find remarkable resemblance for the magneto conductance
oscillations in both conductance and visibility between simulations and
experiments within a specific parameter range.


title: Strong pure infiniteness of crossed products

abstract:
  Consider an exact action of discrete group $G$ on a separable $C^*$-algebra
$A$. It is shown that the reduced crossed product $A\rtimes_{\sigma, \lambda}
G$ is strongly purely infinite - provided that the action of $G$ on any
quotient $A/I$ by a $G$-invariant closed ideal $I\neq A$ is element-wise
properly outer and that the action of $G$ on $A$ is $G$-separating (cf.
Definition 4.1). This is the first non-trivial sufficient criterion for strong
pure infiniteness of reduced crossed products of $C^*$-algebras $A$ that are
not $G$-simple. In the case $A=\mathrm{C}_0(X)$ the notion of a $G$-separating
action corresponds to the property that two compact sets $C_1$ and $C_2$, that
are contained in open subsets $C_j\subseteq U_j \subseteq X$, can be mapped by
elements of $g_j\in G$ onto disjoint sets $\sigma_{g_j}(C_j)\subseteq U_j$, but
we do not require that $\sigma_{g_j}(U_j)\subseteq U_j$. A generalization of
strong boundary actions on compact spaces to non-unital and non-commutative
$C^*$-algebras $A$ (cf. Definition 6.1) is also introduced. It is stronger than
the notion of $G$-separating actions by Proposition 6.6, because $G$-separation
does not imply $G$-simplicity and there are examples of $G$-separating actions
with reduced crossed products that are stably projection-less and non-simple.


title:
The unitary cover of a finite group and the exponent of the Schur
  multiplier

abstract:
  For a finite group we introduce a particular central extension, the unitary
cover, having minimal exponent among those satisfying the projective lifting
property. We obtain new bounds for the exponent of the Schur multiplier
relating to subnormal series, and we discover new families for which the bound
is the exponent of the group. Finally, we show that unitary covers are
controlled by the Zel'manov solution of the restricted Burnside problem for
2-generator groups.


title: Starobinsky-type Inflation in Dynamical Supergravity Breaking Scenarios

abstract:
  In the context of dynamical breaking of local supersymmetry (supergravity),
including the Deser-Zumino super-Higgs effect, for the simple but quite
representative cases of N=1, D=4 supergravity, we discuss the emergence of
Starobinsky-type inflation, due to quantum corrections in the effective action
arising from integrating out gravitino fields in their massive phase. This type
of inflation may occur after a first-stage small-field inflation that
characterises models near the origin of the one-loop effective potential, and
it may occur at the non-trivial minima of the latter. Phenomenologically
realistic scenarios, compatible with the Planck data, may be expected for the
conformal supergravity variants of the basic model.


title: Learning Semantic Script Knowledge with Event Embeddings

abstract:
  Induction of common sense knowledge about prototypical sequences of events
has recently received much attention. Instead of inducing this knowledge in the
form of graphs, as in much of the previous work, in our method, distributed
representations of event realizations are computed based on distributed
representations of predicates and their arguments, and then these
representations are used to predict prototypical event orderings. The
parameters of the compositional process for computing the event representations
and the ranking component of the model are jointly estimated from texts. We
show that this approach results in a substantial boost in ordering performance
with respect to previous methods.


title:
A holographic model for QCD in the Veneziano limit at finite temperature
  and density

abstract:
  A holographic model of QCD in the limit of large number of colors, $N_c$, and
massless fermion flavors, $N_f$, but constant ratio $x_f=N_f/N_c$ is analyzed
at finite temperature and chemical potential. The five dimensional gravity
model contains three bulk fields: a scalar dilaton sourcing ${\rm Tr}F^2$, a
scalar tachyon dual to $\bar qq$ and a 4-vector dual to the baryon current
$\bar q \gamma^{\mu} q$. The main result is the $\mu,T$ phase diagram of the
holographic theory. A first order deconfining transition along $T_h(\mu)$ and a
chiral transition at $T_\chi(\mu)>T_h(\mu)$ are found. The chiral transition is
of second order for all $\mu$. The dependence of thermodynamical quantities
including the speed of sound and susceptibilities on the chemical potential and
temperature is computed. A new quantum critical regime is found at zero
temperature and finite chemical potential. It is controlled by an AdS$_2\times
R^3$ geometry and displays semi-local criticality.


title:
Importance of Semi Inclusive DIS Processes in Determining Fragmentation
  Functions

abstract:
  A NLO QCD analysis of the HERMES and COMPASS data on pion multiplicities is
presented. Sets of pion fragmentation functions are extracted from fits to the
data and compared with those obtained from other groups before these data were
available. The consistency between HERMES and COMPASS data is discussed. We
point out a possible inconsistency between the HERMES [x, z] and [Q^2, z]
presentations of their data.


abstract:
  We define the $S^1$-equivariant Rabinowitz-Floer homology of a bounding
contact hypersurface $\Sigma$ in an exact symplectic manifold, and show by a
geometric argument that it vanishes if $\Sigma$ is displaceable.
  In the appendix we describe an approach to transversality for Floer
homologies for which the moduli space $\widehat M_J$ of all gradient flow lines
is compact for some almost complex structure $J$. This approach uses a large
set of perturbations, namely vector fields on the loop space, and selects from
the possibly non-compact perturbed moduli spaces a part near $\widehat M_J$
that turns out to be compact for small enough perturbations.


title: Consensus in the presence of interference

abstract:
  This paper studies distributed strategies for average-consensus of arbitrary
vectors in the presence of network interference. We assume that the underlying
communication on any \emph{link} suffers from \emph{additive interference}
caused due to the communication by other agents following their own consensus
protocol. Additionally, no agent knows how many or which agents are interfering
with its communication. Clearly, the standard consensus protocol does not
remain applicable in such scenarios. In this paper, we cast an algebraic
structure over the interference and show that the standard protocol can be
modified such that the average is reachable in a subspace whose dimension is
complimentary to the maximal dimension of the interference subspaces (over all
of the communication links). To develop the results, we use \emph{information
alignment} to align the intended transmission (over each link) to the
null-space of the interference (on that link). We show that this alignment is
indeed invertible, i.e. the intended transmission can be recovered over which,
subsequently, consensus protocol is implemented. That \emph{local} protocols
exist even when the collection of the interference subspaces span the entire
vector space is somewhat surprising.


title:
Discrete derived categories I: homomorphisms, autoequivalences and
  t-structures

abstract:
  Discrete derived categories were studied initially by Vossieck and later by
Bobi\'nski, Gei\ss, Skowro\'nski. In this article, we describe the homomorphism
hammocks and autoequivalences on these categories. We classify silting objects
and bounded t-structures.


title:
A globally attractive cycle driven by sequential bifurcations containing
  ghost effects in a 3-node yeast cell cycle model

abstract:
  Yeast cells produce daughter cells through a DNA replication and mitosis
cycle associated with checkpoints and governed by the cell cycle regulatory
network. To ensure genome stability and genetic information inheritance, this
regulatory network must be dynamically robust against various fluctuations.
Here we construct a simplified cell cycle model for a budding yeast to
investigate the underlying mechanism that ensures robustness in this process
containing sequential tasks (DNA replication and mitosis). We first establish a
three-variable model and select a parameter set that qualitatively describes
the yeast cell cycle process. Then, through nonlinear dynamic analysis, we
demonstrate that the yeast cell cycle process is an excitable system driven by
a sequence of saddle-node bifurcations with ghost effects. We further show that
the yeast cell cycle trajectory is globally attractive with modularity in both
state and parameter space, while the convergent manifold provides a suitable
control state for cell cycle checkpoints. These results not only highlight a
regulatory mechanism for executing successive cell cycle processes, but also
provide a possible strategy for the synthetic network design of sequential-task
processes.


title: Minimum-cost quantum measurements for quantum information

abstract:
  Knowing about optimal quantum measurements is important for many applications
in quantum information and quantum communication. However, deriving optimal
quantum measurements is often difficult. We present a collection of results for
minimum-cost quantum measurements, and give examples of how they can be used.
Among other results, we show that a minimum-cost measurement for a set of given
pure states is formally equivalent to a minimum-error measurement for mixed
states of those same pure states. For pure symmetric states it turns out that
for a certain class of cost matrices, the minimum-cost measurement is the
square-root measurement. That is, the optimal minimum-cost measurement is in
this case the same as the minimum-error measurement. Finally, we consider
sequences of individual ``local" systems, and examine when the global
minimum-cost measurement is a sequence of optimal local measurements. We also
consider an example where the global minimum-cost measurement is, perhaps
counter-intuitively, not a sequence of local measurements, and discuss how this
is related to related to the Pusey-Barrett-Rudolph argument for the nature of
the wave function.


title: GSI Oscillations as Laboratory for Testing of New Physics

abstract:
  We analyse recent experimental data on the GSI oscillations of the
hydrogen-like heavy {^{142}}{\rm Pm}^{60+} ions that is a time modulation of
the K-shell electron capture (EC) decay rate. We follow the mechanism of the
GSI oscillations, caused by an interference of the neutrino flavour
mass-eigenstates in a content of the electron neutrino. We give arguments that
these experimental data show i) an existence of sterile neutrinos that is
necessary for an explanation of a phase-shift, ii) an observation of CP
violation, related to a phase-shift, and iii) an influence of the Quantum Zeno
Effect, explaining different values of the amplitude and phase-shift for two
runs of measurements with different time resolutions and different numbers of
consecutive measurements.


title: Parameter inference from hitting times for perturbed Brownian motion

abstract:
  A latent internal process describes the state of some system, e.g. the social
tension in a political conflict, the strength of an industrial component or the
health status of a person. When this process reaches a predefined threshold,
the process terminates and an observable event occurs, e.g. the political
conflict finishes, the industrial component breaks down or the person has a
heart attack. Imagine an intervention, e.g., a political decision, maintenance
of a component or a medical treatment, is initiated to the process before the
event occurs. How can we evaluate whether the intervention had an effect?
  To answer this question we describe the effect of the intervention through
parameter changes of the law governing the internal process. Then, the time
interval between the start of the process and the final event is divided into
two subintervals: the time from the start to the instant of intervention,
denoted by $S$, and the time between the intervention and the threshold
crossing, denoted by $R$. The first question studied here is: What is the joint
distribution of $(S,R)$? The theoretical expression is provided and serves as a
basis to answer the main question: Can we estimate the parameters of the model
from observations of $S$ and $R$ and compare them statistically? Maximum
likelihood estimators are illustrated on simulated data under the assumption
that the process before and after the intervention is described by the same
type of model, i.e. a Brownian motion, but with different parameters.


title:
Kaluza-Klein theory revisited: projective structures and differential
  operators on algebra of densities

abstract:
  We consider differential operators acting on densities of arbitrary weights
on manifold $M$ identifying pencils of such operators with operators on algebra
of densities of all weights. This algebra can be identified with the special
subalgebra of functions on extended manifold $\hat M$. On one hand there is a
canonical lift of projective structures on $M$ to affine structures on extended
manifold $\hat M$. On the other hand the restriction of algebra of all
functions on extended manifold to this special subalgebra of functions implies
the canonical scalar product. This leads in particular to classification of
second order operators with use of Kaluza-Klein-like mechanisms.


title: Forging the link between nuclear reactions and nuclear structure

abstract:
  A comprehensive description of all single-particle properties associated with
the nucleus ${}^{40}$Ca is generated by employing a nonlocal dispersive optical
potential capable of simultaneously reproducing all relevant data above and
below the Fermi energy. The introduction of nonlocality in the absorptive
potentials yields equivalent elastic differential cross sections as compared to
local versions but changes the absorption profile as a function of angular
momentum suggesting important consequences for the analysis of nuclear
reactions. Below the Fermi energy, nonlocality is essential to allow for an
accurate representation of particle number and the nuclear charge density.
Spectral properties implied by $(e,e'p)$ and $(p,2p)$ reactions are correctly
incorporated, including the energy distribution of about 10% high-momentum
nucleons, as experimentally determined by data from Jefferson Lab. These
high-momentum nucleons provide a substantial contribution to the energy of the
ground state, indicating a residual attractive contribution from higher-body
interactions for ${}^{40}$Ca of about 0.64 MeV/$A$.


title: Brief note on high-multipole Kerr tails

abstract:
  In this note we reconsider the late-time, power-law decay rate of scalar
fields in a Kerr space-time background. We implement a number of mathematical
and computational enhancements to our time-domain, (2+1)D Teukolsky evolution
code and are able to obtain reliable decay rates for multipoles as high as
$\ell=16$. Our numerical results suggest full agreement with the proposed decay
expressions in recent work for both the finite distance, and null infinity
cases. We also study the same in the context of extremal Kerr space-time and
find that the same results hold, except that the horizon tails follow the null
infinity expressions instead.


title: HT Cas - eclipsing dwarf nova during its superoutburst in 2010

abstract:
  We present results of a world-wide observing campaign of the eclipsing dwarf
nova - HT Cas during its superoutburst in November 2010. Using collected data
we were able to conduct analysis of the light curves and we calculated $O-C$
diagrams.
  The CCD photometric observations enabled us to derive the superhump period
and with the timings of eclipses the orbital period was calculated. Based on
superhump and orbital period estimations the period excess and mass ratio of
the system were obtained.


title:
Saccade learning with concurrent cortical and subcortical basal ganglia
  loops

abstract:
  The Basal Ganglia is a central structure involved in multiple cortical and
subcortical loops. Some of these loops are believed to be responsible for
saccade target selection. We study here how the very specific structural
relationships of these saccadic loops can affect the ability of learning
spatial and feature-based tasks.
  We propose a model of saccade generation with reinforcement learning
capabilities based on our previous basal ganglia and superior colliculus
models. It is structured around the interactions of two parallel cortico-basal
loops and one tecto-basal loop. The two cortical loops separately deal with
spatial and non-spatial information to select targets in a concurrent way. The
subcortical loop is used to make the final target selection leading to the
production of the saccade. These different loops may work in concert or disturb
each other regarding reward maximization. Interactions between these loops and
their learning capabilities are tested on different saccade tasks.
  The results show the ability of this model to correctly learn basic target
selection based on different criteria (spatial or not). Moreover the model
reproduces and explains training dependent express saccades toward targets
based on a spatial criterion.
  Finally, the model predicts that in absence of prefrontal control, the
spatial loop should dominate.


title: Logical Error Rate Scaling of the Toric Code

abstract:
  To date, a great deal of attention has focused on characterizing the
performance of quantum error correcting codes via their thresholds, the maximum
correctable physical error rate for a given noise model and decoding strategy.
Practical quantum computers will necessarily operate below these thresholds
meaning that other performance indicators become important. In this work we
consider the scaling of the logical error rate of the toric code and
demonstrate how, in turn, this may be used to calculate a key performance
indicator. We use a perfect matching decoding algorithm to find the scaling of
the logical error rate and find two distinct operating regimes. The first
regime admits a universal scaling analysis due to a mapping to a statistical
physics model. The second regime characterizes the behavior in the limit of
small physical error rate and can be understood by counting the error
configurations leading to the failure of the decoder. We present a conjecture
for the ranges of validity of these two regimes and use them to quantify the
overhead -- the total number of physical qubits required to perform error
correction.


title: Charged lepton flavor violation and the origin of neutrino masses

abstract:
  The neutrino oscillations imply that charged lepton flavor violation (CLFV)
processes do exist. Even if the associated rates are in general expected very
suppressed, it turns out that this is not always necessarily the case. In the
framework of the three basic seesaw models, we review the possibilities of
having observable rates and thus, in this way, of distinguishing these possible
neutrino mass origins.


title: Properties of strange vector mesons in dense and hot matter

abstract:
  We investigate the in-medium properties of strange vector mesons ($K^*$ and
$\bar K^*$) in dense and hot nuclear matter based on chirally motivated models
of the meson selfenergies. We parameterise medium effects as density or
temperature dependent effective masses and widths, obtain the vector meson
spectral functions within a Breit-Wigner prescription (as often used in
transport simulations) and study whether such an approach can retain the
essential features of full microscopic calculations. For $\mu_B\ne 0$ the
medium corrections arise from $\bar K^* (K^*) N$ scattering and the $\bar K^*
(K^*) \to \bar K (K) \pi$ decay mode (accounting for in-medium $\bar K (K)$
dynamics). We calculate the scattering contribution to the $K^*$ selfenergy
based on the hidden local symmetry formalism for vector meson nucleon
interactions, whereas for the $\bar K^*$ selfenergy we implement recent results
from a selfconsistent coupled-channel determination within the same approach.
For $\mu_B\simeq 0$ and finite temperature we rely on a phenomenological
approach for the kaon selfenergy in a hot pionic medium consistent with chiral
symmetry, and evaluate the $\bar K^* (K^*) \to \bar K (K) \pi$ decay width. The
emergence of a mass shift at finite temperature is studied with a dispersion
relation over the imaginary part of the vector meson selfenergy.


title:
Basin of attraction for turbulent thermalization and the range of
  validity of classical-statistical simulations

abstract:
  Different thermalization scenarios for systems with large fields have been
proposed in the literature based on classical-statistical lattice simulations
approximating the underlying quantum dynamics. We investigate the range of
validity of these simulations for condensate driven as well as fluctuation
dominated initial conditions for the example of a single component scalar field
theory. We show that they lead to the same phenomenon of turbulent
thermalization for the whole range of (weak) couplings where the
classical-statistical approach is valid. In the turbulent regime we establish
the existence of a dual cascade characterized by universal scaling exponents
and scaling functions. This complements previous investigations where only the
direct energy cascade has been studied for the single component theory. A
proposed alternative thermalization scenario for stronger couplings is shown to
be beyond the range of validity of classical-statistical simulations.


title: Photon correlations for colloidal nanocrystals and their clusters

abstract:
  Images of semiconductor `dot in rods' and their small clusters are studied by
measuring the second-order correlation function with a spatially resolving ICCD
camera. This measurement allows one to distinguish between a single dot and a
cluster and, to a certain extent, to estimate the number of dots in a cluster.
A more advanced measurement is proposed, based on higher-order correlations,
enabling more accurate determination of the number of dots in a small cluster.
Nonclassical features of the light emitted by such a cluster are analyzed.


title: Electron transport in quantum wire superlattices

abstract:
  Electronic transport is theoretically investigated in laterally confined
semiconductor superlattices using the formalism of non-equilibrium Green's
functions. The transport properties are calculated for nanowire superlattices
of varying diameters, from the quantum dot superlattice regime to the quantum
well superlattice regime. Scattering processes due to electron-phonon
couplings, phonon anharmonicity, charged impurities, surface and interface
roughness and alloy disorder are included on a microscopic basis. Elastic
scattering mechanisms are treated in a partial coherent way beyond the
self-consistent Born approximation. The nature of transport along the
superlattice is shown to depend dramatically on the lateral dimensionality. In
the quantum wire regime, the electron velocity-field characteristics are
predicted to deviate strongly from the standard Esaki-Tsu form, with pronounced
current peaks due to integer and fractional resonances with optical phonons.


title: Maximum entropy copula with given diagonal section

abstract:
  We consider copulas with a given diagonal section and compute the explicit
density of the unique optimal copula which maximizes the entropy. In this
sense, this copula is the least informative among the copulas with a given
diagonal section. We give an explicit criterion on the diagonal section for the
existence of the optimal copula and give a closed formula for its entropy. We
also provide examples for some diagonal sections of usual bivariate copulas and
illustrate the differences between them and the maximum entropy copula with the
same diagonal section.


title: A Fake Split Supersymmetry Model for the 126 GeV Higgs

abstract:
  We consider a scenario where supersymmetry is broken at a high energy scale,
out of reach of the LHC, but leaves a few fermionic states at the TeV scale.
The particle content of the low-energy effective theory is similar to that of
Split Supersymmetry. However, the gauginos and higgsinos are replaced by
fermions carrying the same quantum numbers but having different couplings,
which we call fake gauginos and fake higgsinos. We study the prediction for the
light-Higgs mass in this Fake Split SUSY Model (FSSM). We find that, in
contrast to Split or high-scale supersymmetry, a 126 GeV Higgs boson is easily
obtained even for arbitrarily high values of the supersymmetry scale. For a
supersymmetry scale greater than roughly 100 PeV, the Higgs mass is almost
independent of the supersymmetry scale and the stop mixing parameter, while the
observed value is achieved for tan beta between 1.3 and 1.8 depending on the
gluino mass.


title:
Signatures of anisotropic sources in the trispectrum of the cosmic
  microwave background

abstract:
  Soft limits of $N$-point correlation functions, in which one wavenumber is
much smaller than the others, play a special role in constraining the physics
of inflation. Anisotropic sources such as a vector field during inflation
generate distinct angular dependence in all these correlators. In this paper we
focus on the four-point correlator (the trispectrum $T$). We adopt a
parametrization motivated by models in which the inflaton $\phi$ is coupled to
a vector field through a $I^2 \left( \phi \right) F^2$ interaction, namely
$T_{\zeta}({\bf k}_1, {\bf k}_2, {\bf k}_3, {\bf k}_4) \equiv \sum_n d_n [
P_n(\hat{\bf k}_1 \cdot \hat{\bf k}_3) + P_n(\hat{\bf k}_1 \cdot \hat{\bf
k}_{12}) + P_n(\hat{\bf k}_3 \cdot \hat{\bf k}_{12}) ] P_{\zeta}(k_1)
P_{\zeta}(k_3) P_\zeta(k_{12}) + (23~{\rm perm})$, where $P_n$ denotes the
Legendre polynomials. This shape is enhanced when the wavenumbers of the
diagonals of the quadrilateral are much smaller than the sides, ${\bf k}_i$.
The coefficient of the isotropic part, $d_0$, is equal to $\tau_{\rm NL}/6$
discussed in the literature. A $I^2 \left( \phi \right) F^2$ interaction
generates $d_2 = 2 d_0$ which is, in turn, related to the quadrupole modulation
parameter of the power spectrum, $g_*$, as $d_2 \approx 14 |g_*| N^2$ with $N
\approx 60$. We show that $d_0$ and $d_2$ can be equally well-constrained: the
expected $68 \%$ CL error bars on these coefficients from a
cosmic-variance-limited experiment measuring temperature anisotropy of the
cosmic microwave background up to $\ell_{\rm max}=2000$ are $\delta d_2 \approx
4 \delta d_0 = 105$. Therefore, we can reach $|g_*|=10^{-3}$ by measuring the
angle-dependent trispectrum. The current upper limit on $\tau_{\rm NL}$ from
the ${\it Planck}$ temperature maps yields $|g_*|<0.02$ ($95 \%$ CL).


title:
Predicting Lepton Flavor Mixing from $\Delta(48)$ and Generalized CP
  Symmetries

abstract:
  We propose to understand the mixing angles and CP-violating phases from the
$\Delta(48)$ family symmetry combined with the generalized CP symmetry. A
model-independent analysis is performed by scanning all the possible symmetry
breaking chains. We find a new mixing pattern with only one free parameter,
excellent agreement with the observed mixing angles can be achieved and all the
CP-violating phases are predicted to take nontrivial values. This mixing
pattern is testable in the near future neutrino oscillation and neutrinoless
double-beta decay experiments. Finally, a flavor model is constructed to
realize this mixing pattern.


title: Density of states of the $XY$ model: an energy landscape approach

abstract:
  Among the stationary configurations of the Hamiltonian of a classical O$(n)$
lattice spin model, a class can be identified which is in one-to-one
correspondence with all the the configurations of an Ising model defined on the
same lattice and with the same interactions. Starting from this observation it
has been recently proposed that the microcanonical density of states of an
O$(n)$ model could be written in terms of the density of states of the
corresponding Ising model. Later, it has been shown that a relation of this
kind holds exactly for two solvable models, the mean-field and the
one-dimensional $XY$ model, respectively. We apply the same strategy to derive
explicit, albeit approximate, expressions for the density of states of the
two-dimensional $XY$ model with nearest-neighbor interactions on a square
lattice. The caloric curve and the specific heat as a function of the energy
density are calculated and compared against simulation data, yielding a very
good agreement over the entire energy density range. The concepts and methods
involved in the approximations presented here are valid in principle for any
O$(n)$ model.


title:
The passive and active periods for the intermittent use of an active
  sensor to detect an evasive target

abstract:
  Your task is to detect a submarine with your active sonar. The submarine can
hear your active sonar before you can detect him. If the submarine is fast
enough he can evade you before you can detect him. How do you then detect him?
If you are using your active sonar continuously you will not detect him.
Likewise, if you are not using your sonar at all. In between those two extremes
there is an optimum. We will find that optimum. Or said more precisely and
general: In the same two dimensional region two platforms are present. One
platform, the searcher, equipped with one active sensor (sonar, radar, lidar
etc.), is trying to detect the other platform, the target, by means of its
active sensor. The target tries to avoid detection using only a passive sensor
to detect the searcher. The target can detect the active sensor before the
searcher can detect the target (forestalling). The active sensor is therefore
used intermittently to surprise the target. The aim of this study is to
quantify the passive period of the active sensor by minimizing missed detection
opportunities. The active period is subsequently found by maximizing the
average detection width of the searcher sensor over time.


title:
Security of the Improved Fuzzy Vault Scheme in the Presence of Record
  Multiplicity (Full Version)

abstract:
  Dodis et al. proposed an improved version of the fuzzy vault scheme, one of
the most popular primitives used in biometric cryptosystems, requiring less
storage and leaking less information. Recently, Blanton and Aliasgari have
shown that the relation of two improved fuzzy vault records of the same
individual may be determined by solving a system of non-linear equations.
However, they conjectured that this is feasible for small parameters only. In
this paper, we present a new attack against the improved fuzzy vault scheme
based on the extended Euclidean algorithm that determines if two records are
related and recovers the elements by which the protected features, e.g., the
biometric templates, differ. Our theoretical and empirical analysis
demonstrates that the attack is very effective and efficient for practical
parameters. Furthermore, we show how this attack can be extended to fully
recover both feature sets from related vault records much more efficiently than
possible by attacking each record individually. We complement this work by
deriving lower bounds for record multiplicity attacks and use these to show
that our attack is asymptotically optimal in an information theoretic sense.
Finally, we propose remedies to harden the scheme against record multiplicity
attacks.


title:
Solar Magnetized Tornadoes: Rotational Motion in a Tornado-like
  Prominence

abstract:
  Su et al. 2012 proposed a new explanation for filament formation and
eruption, where filament barbs are rotating magnetic structures driven by
underlying vortices on the surface. Such structures have been noticed as
tornado-like prominences when they appear above the limb. They may play a key
role as the source of plasma and twist in filaments. However, no observations
have successfully distinguished rotational motion of the magnetic structures in
tornado-like prominences from other motions such as oscillation and
counter-streaming plasma flows. Here we report evidence of rotational motions
in a tornado-like prominence. The spectroscopic observations in two coronal
lines were obtained from a specifically designed Hinode/EIS observing program.
The data revealed the existence of both cold and million-degree-hot plasma in
the prominence leg, supporting the so-called "the prominence-corona transition
region". The opposite velocities at the two sides of the prominence and their
persistent time evolution, together with the periodic motions evident in
SDO/AIA dark structures, indicate a rotational motion of both cold and hot
plasma with a speed of $\sim$5 km s$^{-1}$.


title: Inverse limit spaces satisfying a Poincare inequality

abstract:
  We give conditions on Gromov-Hausdorff convergent inverse systems of metric
measure graphs (and certain higher dimensional inverse systems of metric
measure spaces) which imply that the measured Gromov-Hausdorff limit
(equivalently, the inverse limit) is a PI space, i.e. it satisfies a doubling
condition and a Poincare inequality in the sense of Heinonen-Koskela. We also
give a systematic construction of examples for which our conditions are
satisfied. Included are known examples of PI spaces, such as Laakso spaces, and
a large class of new examples. Generically our graph examples have the property
that they do not bilipschitz embed in any Banach space with Radon-Nikodym
property, but they do embed in the Banach space L_1. For Laakso spaces, these
facts were discussed in our earlier papers.


title:
Uniform sampling of steady states in metabolic networks: heterogeneous
  scales and rounding

abstract:
  The uniform sampling of convex polytopes is an interesting computational
problem with many applications in inference from linear constraints, but the
performances of sampling algorithms can be affected by ill-conditioning. This
is the case of inferring the feasible steady states in models of metabolic
networks, since they can show heterogeneous time scales . In this work we focus
on rounding procedures based on building an ellipsoid that closely matches the
sampling space, that can be used to define an efficient hit-and-run (HR) Markov
Chain Monte Carlo. In this way the uniformity of the sampling of the convex
space of interest is rigorously guaranteed, at odds with non markovian methods.
We analyze and compare three rounding methods in order to sample the feasible
steady states of metabolic networks of three models of growing size up to
genomic scale. The first is based on principal component analysis (PCA), the
second on linear programming (LP) and finally we employ the lovasz ellipsoid
method (LEM). Our results show that a rounding procedure is mandatory for the
application of the HR in these inference problem and suggest that a combination
of LEM or LP with a subsequent PCA perform the best. We finally compare the
distributions of the HR with that of two heuristics based on the Artificially
Centered hit-and-run (ACHR), gpSampler and optGpSampler. They show a good
agreement with the results of the HR for the small network, while on genome
scale models present inconsistencies.


title:
Gibbsian and non-Gibbsian properties of the generalized mean-field fuzzy
  Potts-model

abstract:
  We analyze the generalized mean-field q-state Potts model which is obtained
by replacing the usual quadratic interaction function in the mean-field
Hamiltonian by a higher power z. We first prove a generalization of the known
limit result for the empirical magnetization vector of Ellis and Wang which
shows that in the right parameter regime, the first-order phase-transition
persists. Next we turn to the corresponding generalized fuzzy Potts model which
is obtained by decomposing the set of the q possible spin-values into 1 < s < q
classes and identifying the spins within these classes. In extension of earlier
work which treats the quadratic model we prove the following: The fuzzy Potts
model with interaction exponent bigger than four (respectively bigger than two
and smaller or equal four) is non-Gibbs if and only if its inverse temperature
is larger or equal than the critical inverse temperature of the corresponding
Potts model with number of spin-labels equal to the size of the smallest class
which is greater or equal than two (respectively greater or equal than three.)
We also provide a dynamical interpretation considering sequences of fuzzy Potts
models which are obtained by increasingly collapsing classes at finitely many
times and discuss the possibility of a multiple in- and out of Gibbsianness,
depending on the collapsing scheme.


title:
Neutrinos in the Early Universe, Kalb-Ramond Torsion and
  Matter-Antimatter Asymmetry

abstract:
  The generation of a matter-antimatter asymmetry in the Universe may be
induced by the propagation of fermions in non-trivial, spherically asymmetric
(and hence Lorentz violating) gravitational backgrounds. Such backgrounds may
characterise the epoch of the early universe. The key point in these models is
that the background induces different dispersion relations, hence populations,
between fermions and antifermions, and thus CPT Violation (CPTV) appears in
thermal equilibrium. Species populations may freeze out leading to leptogenesis
and baryogenesis. We consider here a string-inspired scenario, in which the
CPTV is associated with a cosmological background with torsion provided by the
Kalb-Ramond (KR) antisymemtric tensor field of the string gravitational
multiplet. In a four-dimensional space time this field is dual to a
pseudoscalar ``axion-like'' field. The mixing of the KR field with an ordinary
axion field can lead to the generation of a Majorana neutrino mass.


title:
Tortuosity Entropy: a measure of spatial complexity of behavioral
  changes in animal movement data

abstract:
  The goal of animal movement analysis is to understand how organisms explore
and exploit the complex and varying environment. Animals usually exhibit varied
and complicated movements, from apparently deterministic behaviors to highly
random ones. This is critical for assessing movement efficiency and strategies
that are used to quantify and analyze movement trajectories. Here we introduce
a tortuosity entropy (TorEn) based on comparison of parameters, e.g. heading,
bearing, speed, of consecutive points in movement trajectory, which is a simple
measure for quantifying the behavioral change in animal movement data in a fine
scale. In our approach, the differences between pairwise successive track
points are transformed inot symbolic sequences, then we map these symbols into
a group of pattern vectors and calculate the information entropy of pattern
vector. Tortuosity entropy can be easily applied to arbitrary real-world
data-deterministic or stochastic, stationary or non-stationary. We test the
algorithm on both simulated trajectories and real trajectories and show that
both mixed segments in synthetic data and different phases in real movement
data are identified accurately. The results show that the algorithm is
applicable to various situations, indicating that our approach is a promising
tool to reveal the behavioral pattern in movement data.


title:
Tensor ideals and varieties for modules of quantum elementary abelian
  groups

abstract:
  In a previous paper we constructed rank and support variety theories for
"quantum elementary abelian groups," that is, tensor products of copies of Taft
algebras. In this paper we use both variety theories to classify the thick
tensor ideals in the stable module category, and to prove a tensor product
property for the support varieties.


title:
Implications of Improved Higgs Mass Calculations for Supersymmetric
  Models

abstract:
  We discuss the allowed parameter spaces of supersymmetric scenarios in light
of improved Higgs mass predictions provided by FeynHiggs 2.10.0. The Higgs mass
predictions combine Feynman-diagrammatic results with a resummation of leading
and subleading logarithmic corrections from the stop/top sector, which yield a
significant improvement in the region of large stop masses. Scans in the pMSSM
parameter space show that, for given values of the soft supersymmetry-breaking
parameters, the new logarithmic contributions beyond the two-loop order
implemented in FeynHiggs tend to give larger values of the light CP-even Higgs
mass, M_h, in the region of large stop masses than previous predictions that
were based on a fixed-order Feynman-diagrammatic result, though the differences
are generally consistent with the previous estimates of theoretical
uncertainties. We re-analyze the parameter spaces of the CMSSM, NUHM1 and
NUHM2, taking into account also the constraints from CMS and LHCb measurements
of B_s to \mu+\mu- and ATLAS searches for MET events using 20/fb of LHC data at
8 TeV. Within the CMSSM, the Higgs mass constraint disfavours tan beta lesssim
10, though not in the NUHM1 or NUHM2.


title: The cooling rate of neutron stars after thermonuclear shell flashes

abstract:
  Thermonuclear shell flashes on neutron stars are detected as bright X-ray
bursts. Traditionally, their decay is modeled with an exponential function.
However, this is not what theory predicts. The expected functional form for
luminosities below the Eddington limit, at times when there is no significant
nuclear burning, is a power law. We tested the exponential and power-law
functional forms against the best data available: bursts measured with the
high-throughput Proportional Counter Array (PCA) on board the Rossi X-ray
Timing Explorer. We selected a sample of 35 'clean' and ordinary (i.e., shorter
than a few minutes) bursts from 14 different neutron stars that 1) show a large
dynamic range in luminosity, 2) are the least affected by disturbances by the
accretion disk and 3) lack prolonged nuclear burning through the rp-process. We
find indeed that for every burst a power law is a better description than an
exponential function. We also find that the decay index is steep, 1.8 on
average, and different for every burst. This may be explained by contributions
from degenerate electrons and photons to the specific heat capacity of the
ignited layer and by deviations from the Stefan-Boltzmann law due to changes in
the opacity with density and temperature. Detailed verification of this
explanation yields inconclusive results. While the values for the decay index
are consistent, changes of it with the burst time scale, as a proxy of ignition
depth, and with time are not supported by model calculations.


title:
STEREO/HI and Optical Observations of the Classical Nova V5583
  Sagittarii

abstract:
  The classical nova V5583 Sgr (Nova Sagittarii 2009 No 3) has been observed
during the rise phase and shortly after by NASA's STEREO/HI instruments, with
later optical spectroscopy obtained with the R-C Spectrograph at CTIO, Chile.
The time of peak in the STEREO passband has been constrained to within 4 hours,
as a result of the high cadence data obtained by STEREO/HI. The optical spectra
show the nova evolving from the permitted to the nebular phases. The neon
abundance in the ejecta is [Ne/O] > +1:0, which suggests that V5583 Sgr was
most likely a neon nova.


title: The rotation states predominant among the planetary satellites

abstract:
  On the basis of tidal despinning timescale arguments, Peale showed in 1977
that the majority of irregular satellites (with unknown rotation states) are
expected to reside close to their initial (fast) rotation states. Here we
investigate the problem of the current typical rotation states among all known
satellites from a viewpoint of dynamical stability. We explore location of the
known planetary satellites on the ($\omega_0$, $e$) stability diagram, where
$\omega_0$ is an inertial parameter of a satellite and $e$ is its orbital
eccentricity. We show that most of the satellites with unknown rotation states
cannot rotate synchronously, because no stable synchronous 1:1 spin-orbit state
exists for them. They rotate either much faster than synchronously (those
tidally unevolved) or, what is much less probable, chaotically (tidally evolved
objects or captured slow rotators).


title: Quantum and classical capacity boosted by a Lorentz transformation

abstract:
  In this paper we show that the quantum channel between two inertial observers
who transmit quantum information by sending realistic photonic wave packets is
a well-studied channel in quantum Shannon theory -- the Pauli channel. The
parameters of the Pauli channel and therefore its classical and quantum
capacity depend on the magnitude of the Lorentz boost relating the two
observers. The most striking consequence is that two inertial observers whose
Pauli channel has initially zero quantum capacity can achieve nonzero quantum
communication rates (reaching in principle its maximal value equal to one) by
applying a boost in the right direction. This points to a fundamental
connection between quantum channel capacities and special relativity.


title: Positive Integer Powers OF Symmetric(0,1)-Heptadiagonal Matrix

abstract:
  In this paper, we derive a general expression for mth powers of
symmetric(0,1)-heptadiagonal matrices with n = 3k order,k = 1,2,3,...,n/3).


title: OH+ in Diffuse Molecular Clouds

abstract:
  Near ultraviolet observations of OH+ and OH in diffuse molecular clouds
reveal a preference for different environments. The dominant absorption feature
in OH+ arises from a main component seen in CH+ (that with the highest CH+/CH
column density ratio), while OH follows CN absorption. This distinction
provides new constraints on OH chemistry in these clouds. Since CH+ detections
favor low-density gas with small fractions of molecular hydrogen, this must be
true for OH+ as well, confirming OH+ and H2O+ observations with the Herschel
Space Telescope. Our observed correspondence indicates that the cosmic ray
ionization rate derived from these measurements pertains to mainly atomic gas.
The association of OH absorption with gas rich in CN is attributed to the need
for high enough density and molecular fraction before detectable amounts are
seen. Thus, while OH+ leads to OH production, chemical arguments suggest that
their abundances are controlled by different sets of conditions and that they
coexist with different sets of observed species. Of particular note is that
non-thermal chemistry appears to play a limited role in the synthesis of OH in
diffuse molecular clouds.


title: On the coset duals of extended higher spin theories

abstract:
  We study the holographic duality between the M x M matrix extension of
Vasiliev higher spin theories on AdS3 and the large N limit of SU(N+M)/SU(N) x
U(1) type cosets. We present a simplified proof for the agreement of the
spectra and clarify the relation between this duality and the version in which
the cosets are replaced by Kazama-Suzuki models of Grassmannian type.


title:
Non-extensibility of the pair $\{1, 3\}$ to a Diophantine quintuple in
  $\mathbb{Z}\left[\sqrt{-d}\right]$

abstract:
  We show that the Diophantine pair $\{1, 3\}$ can not be extended to a
Diophantine quintuple in $\mathbb{Z}\left[\sqrt{-2}\right]$. This result
completes the work of the first author and establishes non-extensibility of the
Diophantine pair $\{1, 3\}$ to a Diophantine quintuple in
$\mathbb{Z}\left[\sqrt{-d}\right]$ for all $d\in \mathbb{N}$.


title: Unsupervised feature learning by augmenting single images

abstract:
  When deep learning is applied to visual object recognition, data augmentation
is often used to generate additional training data without extra labeling cost.
It helps to reduce overfitting and increase the performance of the algorithm.
In this paper we investigate if it is possible to use data augmentation as the
main component of an unsupervised feature learning architecture. To that end we
sample a set of random image patches and declare each of them to be a separate
single-image surrogate class. We then extend these trivial one-element classes
by applying a variety of transformations to the initial 'seed' patches. Finally
we train a convolutional neural network to discriminate between these surrogate
classes. The feature representation learned by the network can then be used in
various vision tasks. We find that this simple feature learning algorithm is
surprisingly successful, achieving competitive classification results on
several popular vision datasets (STL-10, CIFAR-10, Caltech-101).


title:
Spin correlations in Ca3Co2O6: A polarised-neutron diffraction and Monte
  Carlo study

abstract:
  We present polarised-neutron diffraction measurements of the Ising-like
spin-chain compound Ca3Co2O6 above and below the magnetic ordering temperature
TN. Below TN, a clear evolution from a single-phase spin-density wave (SDW)
structure to a mixture of SDW and commensurate antiferromagnet (CAFM)
structures is observed on cooling. For a rapidly-cooled sample, the majority
phase at low temperature is the SDW, while if the cooling is performed
sufficiently slowly, then the SDW and the CAFM structure coexist between 1.5
and 10 K. Above TN, we use Monte Carlo methods to analyse the magnetic diffuse
scattering data. We show that both intra- and inter-chain correlations persist
above TN, but are essentially decoupled. Intra-chain correlations resemble the
ferromagnetic Ising model, while inter-chain correlations resemble the
frustrated triangular-lattice antiferromagnet. Using previously-published bulk
property measurements and our neutron diffraction data, we obtain values of the
ferromagnetic and antiferromagnetic exchange interactions and the single-ion
anisotropy.


title:
Local structure approximation as a predictor of second order phase
  transitions in asynchronous cellular automata

abstract:
  We show that local structure approximation of sufficiently high order can
predict the existence of second order phase transitions belonging to the
directed percolation university class in $\alpha$-asynchronous cellular
automata.


title:
Interplay between chromoelectric and chromomagnetic gluons in Yang-Mills
  thermodynamics

abstract:
  We propose an effective theory of SU(3) gluonic matter where interactions
between color-electric and color-magnetic gluons are constrained by the center
and scale symmetries. Through matching to the dimensionally-reduced magnetic
theories, the magnetic gluon condensate qualitatively changes its thermal
behavior above the critical temperature. We argue its phenomenological
consequences for the thermodynamics, in particular the dynamical breaking of
scale invariance.


title: Charm: Mixing, CP Violation and Rare Decays at LHCb

abstract:
  Recent results on mixing, CP violation and rare decays in charm physics from
the LHCb experiment are presented. Study of ''wrong-sign'' $D^{0} \rightarrow
K^+ \pi^-$ decays provides the highest precision measurements to date of the
mixing parameters $x^{\prime 2}$ and $y^{\prime}$, and of CP violation in this
decay mode. Direct and indirect CP violation in the $D^0$ system are probed to
a sensitivity of around $10^{-3}$ using $D^0 \rightarrow K^+K^-$ and $D^0
\rightarrow \pi^+\pi^-$ decays and found to be consistent with zero. Searches
for the rare decays $D^+_{(s)} \rightarrow \pi^+\mu^+\mu^-$, $D^+_{(s)}
\rightarrow \pi^-\mu^+\mu^+$ and $D^0 \rightarrow \mu^+\mu^-$ find no evidence
of signal, but set the best limits on branching fractions to date. Thus,
despite many excellent results in charm physics from LHCb, no evidence for
physics beyond the Standard Model is found.


title: Mode coupling mechanism for late-time Kerr tails

abstract:
  We consider the decay rate for scalar fields in Kerr spacetime. We consider
pure initial (azimuthal) multipoles $\ell'$ with respect to the class which
includes Boyer-Lindquist coordinates, and focus attention on the decay rate of
the multipole $\ell$. We use an iterative method proposed by Gleiser, Price,
and Pullin, and identify the mode coupling mechanism through the iterations in
powers of the square of the Kerr black hole's specific angular momentum that
gives rise to a decay rate formula recently proposed by Zengino\u{g}lu, Khanna,
and Burko. Modes $\ell$ may be excited through different channels, each leading
to its own decay rate. The asymptotic decay rate of the mode $\ell$ is the
slowest of the decay rate of the various channels. In some cases, more than one
channel leads to the same decay rate, and then the amplitude of the mode is the
sum of the amplitudes of the partial fields generated by the individual
channels. We also show that one may identify the asymptotically-dominant
channel of mode excitations, and obtain approximate results for the mode of
interest by studying the dominant channel. The results of the dominant channel
approximation approach the full-mode results at late times, and their
difference approaches zero quadratically in inverse time.


title: On the number of $K_4$-saturating edges

abstract:
  Let $G$ be a $K_4$-free graph, an edge in its complement is a
$K_4$-\emph{saturating} edge if the addition of this edge to $G$ creates a copy
of $K_4$. Erd\H{o}s and Tuza conjectured that for any $n$-vertex $K_4$-free
graph $G$ with $\lfloor n^2/4\rfloor+1$ edges, one can find at least
$(1+o(1))\frac{n^2}{16}$ $K_4$-saturating edges. We construct a graph with only
$\frac{2n^2}{33}$ $K_4$-saturating edges. Furthermore, we prove that it is best
possible, i.e., one can always find at least $(1+o(1))\frac{2n^2}{33}$
$K_4$-saturating edges in an $n$-vertex $K_4$-free graph with $\lfloor
n^2/4\rfloor+1$ edges.


title:
Existence and Uniqueness theory for the fractional Schr\"odinger
  equation on the torus

abstract:
  We study the Cauchy problem for the $1$-d periodic fractional Schr\"odinger
equation with cubic nonlinearity. In particular we prove local well-posedness
in Sobolev spaces, for solutions evolving from rough initial data. In addition
we show the existence of global-in-time infinite energy solutions. Our tools
include a new Strichartz estimate on the torus along with ideas that Bourgain
developed in studying the periodic cubic NLS.