title: Elliptical instability in hot Jupiter systems

abstract:
  Several studies have already considered the influence of tides on the
evolution of systems composed of a star and a close-in companion to tentatively
explain different observations such as the spin-up of some stars with hot
Jupiters, the radius anomaly of short orbital period planets and the
synchronization or quasi-synchronization of the stellar spin in some extreme
cases. However, the nature of the mechanism responsible for the tidal
dissipation in such systems remains uncertain. In this paper, we claim that the
so-called elliptical instability may play a major role in these systems,
explaining some systematic features present in the observations. This
hydrodynamic instability, arising in rotating flows with elliptical
streamlines, is suspected to be present in both planet and star of such
systems, which are elliptically deformed by tides. The presence and the
influence of the elliptical instability in gaseous bodies, such as stars or hot
Jupiters, are most of the time neglected. In this paper, using numerical
simulations and theoretical arguments, we consider several features associated
to the elliptical instability in hot-Jupiter systems. In particular, the use of
ad hoc boundary conditions makes it possible to estimate the amplitude of the
elliptical instability in gaseous bodies. We also consider the influence of
compressibility on the elliptical instability, and compare the results to the
incompressible case. We demonstrate the ability for the elliptical instability
to grow in the presence of differential rotation, with a possible synchronized
latitude, provided that the tidal deformation and/or the rotation rate of the
fluid are large enough. Moreover, the amplitude of the instability for a
centrally-condensed mass of fluid is of the same order of magnitude as for an
incompressible fluid for a given distance to the threshold of the instability.
Finally, we show that the assumption of the elliptical instability being the
main tidal dissipation process in eccentric inflated hot Jupiters and
misaligned stars is consistent with current data.


title: A New Method to Compute the 2-adic Complexity of Binary Sequences

abstract:
  In this paper, a new method is presented to compute the 2-adic complexity of
pseudo-random sequences. With this method, the 2-adic complexities of all the
known sequences with ideal 2-level autocorrelation are uniformly determined.
Results show that their 2-adic complexities equal their periods. In other
words, their 2-adic complexities attain the maximum. Moreover, 2-adic
complexities of two classes of optimal autocorrelation sequences with period
$N\equiv1\mod4$, namely Legendre sequences and Ding-Helleseth-Lam sequences,
are investigated. Besides, this method also can be used to compute the linear
complexity of binary sequences regarded as sequences over other finite fields.


title: Wall attraction and repulsion of hydrodynamically interacting particles

abstract:
  We investigate hydrodynamic interaction effects between colloidal particles
in the vicinity of a wall in the low Reynolds-number limit. Hydrodynamically
interacting pairs of beads being dragged by a force parallel to a wall, as for
instance during sedimentation, are repelled by the boundary. If a pair of beads
is trapped by harmonic potentials parallel to the external flow and at the same
distance to a wall, then the particle upstream is repelled from the boundary
while its neighbor downstream is attracted. The free end of a semiflexible
bead-spring polymer-model, which is fixed at one end in a flow near a wall, is
bent towards the wall by the same reason. The results obtained for point-like
particles are exemplarily confirmed by fluid particle dynamics simulations for
beads of finite radii, where the shear induced particle rotations either weaken
or enhance the the effects obtained for point-like particles.


title: A lattice QCD study of generalized gluelumps

abstract:
  Proposals for physics beyond the standard model often include new colored
particles at or beyond the scale of electroweak symmetry breaking. Any new
particle with a sufficient lifetime will bind with standard model gluons and
quarks to form a spectrum of new hadrons. Here we focus on colored particles in
the octet, decuplet, 27-plet, 28-plet and 35-plet representations of SU(3)
color because these can form hadrons without valence quarks. In every case,
lattice creation operators are constructed for all angular momentum, parity and
charge conjugation quantum numbers. Computations with fully-dynamical lattice
QCD configurations produce numerical results for mass splittings within this
new hadron spectrum. A previous quenched lattice study explored the octet case
for certain quantum number choices, and our findings provide a reassessment of
those early results.


title: Topology preserving thinning for cell complexes

abstract:
  A topology preserving skeleton is a synthetic representation of an object
that retains its topology and many of its significant morphological properties.
The process of obtaining the skeleton, referred to as skeletonization or
thinning, is a very active research area. It plays a central role in reducing
the amount of information to be processed during image analysis and
visualization, computer-aided diagnosis or by pattern recognition algorithms.
  This paper introduces a novel topology preserving thinning algorithm which
removes \textit{simple cells}---a generalization of simple points---of a given
cell complex. The test for simple cells is based on \textit{acyclicity tables}
automatically produced in advance with homology computations. Using acyclicity
tables render the implementation of thinning algorithms straightforward.
Moreover, the fact that tables are automatically filled for all possible
configurations allows to rigorously prove the generality of the algorithm and
to obtain fool-proof implementations. The novel approach enables, for the first
time, according to our knowledge, to thin a general unstructured simplicial
complex. Acyclicity tables for cubical and simplicial complexes and an open
source implementation of the thinning algorithm are provided as additional
material to allow their immediate use in the vast number of practical
applications arising in medical imaging and beyond.


title: Critical scalar field collapse in AdS_3: an analytic approach

abstract:
  We present an analytical solution of a massless scalar field collapsing in a
three dimensional space-time with a negative cosmological constant, i.e.
asymptotically AdS_3. The Einstein and scalar field equations are formulated
using double null Poincare coordinates. Trapping horizons form when a critical
parameter is p > 1. There are indications that the horizon radius r_AH scales
like r_AH ~ (p-1)^(1/4) and the black hole mass as M ~ r_AH^2 ~ (p-1)^(1/2),
i.e. with a critical mass exponent of 1/2.


title:
SimGrid: a Sustained Effort for the Versatile Simulation of Large Scale
  Distributed Systems

abstract:
  In this paper we present Simgrid, a toolkit for the versatile simulation of
large scale distributed systems, whose development effort has been sustained
for the last fifteen years. Over this time period SimGrid has evolved from a
one-laboratory project in the U.S. into a scientific instrument developed by an
international collaboration. The keys to making this evolution possible have
been securing of funding, improving the quality of the software, and increasing
the user base. In this paper we describe how we have been able to make advances
on all three fronts, on which we plan to intensify our efforts over the
upcoming years.


title: Partizan Kayles and Misere Invertibility

abstract:
  The impartial combinatorial game Kayles is played on a row of pins, with
players taking turns removing either a single pin or two adjacent pins. A
natural partizan variation is to allow one player to remove only a single pin
and the other only a pair of pins. This paper develops a complete solution for
"Partizan Kayles" under misere play, including the misere monoid all possible
sums of positions, and discusses its significance in the context of misere
invertibility: the universe of Partizan Kayles contains a position whose
additive inverse is not its negative, and, moreover, this position is an
example of a right-win game whose inverse is previous-win.


title:
The least eigenvalue of signless Laplacian of non-bipartite graphs with
  given domination number

abstract:
  Let $G$ be a connected non-bipartite graph on $n$ vertices with domination
number $\gamma \le \frac{n+1}{3}$. We investigate the least eigenvalue of the
signless Laplacian of $G$, and present a lower bound for such eigenvalue in
terms of the domination number $\gamma$.


title:
A study of the density functional methods on the photoabsorption of
  Bodipy dyes

abstract:
  Tunability of the photoabsorption and directional charge injection
characteristics of Bodipy-based dye molecules with different carbonyl groups
make them promising candidates for photovoltaic applications. In order to study
the effect of screening in the Coulomb interaction on the electronic and
optical properties of two Bodipy derivatives, we have used linear response
time-dependent and exact exchange hybrid density functional approaches. The
effect of linear and non-linear solvation models on the electrochemical
properties of the dyes has also been discussed.


title: Boundary crossover in non-equilibrium growth processes

abstract:
  The growth of stochastic interfaces in the vicinity of a boundary and the
non-trivial crossover towards the behaviour deep in the bulk is analysed. The
causal interactions of the interface with the boundary lead to a roughness
larger near to the boundary than deep in the bulk. This is exemplified in the
semi-infinite Edwards-Wilkinson model in one dimension, both from its exact
solution and numerical simulations, as well as from simulations on the
semi-infinite one-dimensional Kardar-Parisi-Zhang model. The non-stationary
scaling of interface heights and widths is analyzed and a universal scaling
form for the local height profile is proposed.

categories: cond-mat.stat-mech hep-th math-ph math.MP nlin.CD


title: Phase diagram for a copolymer in a micro-emulsion

abstract:
  In this paper we study a model describing a copolymer in a micro-emulsion.
The copolymer consists of a random concatenation of hydrophobic and hydrophilic
monomers, the micro-emulsion consists of large blocks of oil and water arranged
in a percolation-type fashion. The interaction Hamiltonian assigns energy
$-\alpha$ to hydrophobic monomers in oil and energy $-\beta$ to hydrophilic
monomers in water, where $\alpha,\beta$ are parameters that without loss of
generality are taken to lie in the cone $\{(\alpha,\beta)
\in\mathbb{R}^2\colon\,\alpha \geq |\beta|\}$. Depending on the values of these
parameters, the copolymer either stays close to the oil-water interface
(localization) or wanders off into the oil and/or the water (delocalization).
Based on an assumption about the strict concavity of the free energy of a
copolymer near a linear interface, we derive a variational formula for the
quenched free energy per monomer that is column-based, i.e., captures what the
copolymer does in columns of different type. We subsequently transform this
into a variational formula that is slope-based, i.e., captures what the polymer
does as it travels at different slopes, and we use the latter to identify the
phase diagram in the $(\alpha,\beta)$-cone. There are two regimes:
supercritical (the oil blocks percolate) and subcritical (the oil blocks do not
percolate). The supercritical and the subcritical phase diagram each have two
localized phases and two delocalized phases, separated by four critical curves
meeting at a quadruple critical point. The different phases correspond to the
different ways in which the copolymer can move through the micro-emulsion. The
analysis of the phase diagram is based on three hypotheses of percolation-type
on the blocks. We show that these three hypotheses are plausible, but do not
provide a proof.


title: Spin density wave order and fluctuations in Mn3Si: a transport study

abstract:
  We present a comprehensive transport investigation of the itinerant
antiferromagnet Mn3Si which undergoes a spin density wave (SDW) order below
T_N~21.3K. The electrical resistivity, the Hall-, Seebeck and Nernst effects
exhibit pronounced anomalies at the SDW transition, while the heat conductivity
is phonon dominated and therefore is insensitive to the intrinsic electronic
ordering in this compound. At temperatures higher than T_N our data provide
strong evidence for a large fluctuation regime which extends up to ~200K in the
resistivity, the Seebeck effect and the Nernst effect. From the comparison of
our results with other prototype SDW materials, viz. LaFeAsO and Chromium, we
conclude that many of the observed features are of generic character.


title: The $g_{J/\psi D_s D_s}$ strong coupling constant from QCD Sum Rules

abstract:
  The coupling constant of the meson vertex $J/\psi D_s D_s$ is calculated
using the three point correlation function within the QCD Sum Rule formalism.
We have considered alternately mesons $J/\psi$ and $D_s$ off-shell together
with non-perturbative contributions up to the mixed quark-gluon condensates.
When extrapolated, these two different form factors give the same coupling
constant for the process $g_{J/\psi D_s D_s} = 5.98^{+0.67}_{-0.58}$.


title:
Neutrino mass hierarchy and electron neutrino oscillation parameters
  with one hundred thousand reactor events

abstract:
  Proposed medium-baseline reactor neutrino experiments offer unprecedented
opportunities to probe, at the same time, the mass-mixing parameters which
govern $\nu_e$ oscillations both at short wavelength (delta m^2 and theta_{12})
and at long wavelength (Delta m^2 and theta_{13}), as well as their tiny
interference effects related to the mass hierarchy (i.e., the relative sign of
Delta m^2 and delta m^2). In order to take full advantage of these
opportunities, precision calculations and refined statistical analyses of event
spectra are required. In such a context, we revisit several input ingredients,
including: nucleon recoil in inverse beta decay and its impact on energy
reconstruction and resolution, hierarchy and matter effects in the oscillation
probability, spread of reactor distances, irreducible backgrounds from
geoneutrinos and from far reactors, and degeneracies between energy scale and
spectrum shape uncertainties. We also introduce a continuous parameter alpha,
which interpolates smoothly between normal hierarchy (alpha=+1) and inverted
hierarchy (alpha=-1). The determination of the hierarchy is then transformed
from a test of hypothesis to a parameter estimation, with a sensitivity given
by the distance of the true case (either alpha=+1 or alpha=-1) from the
undecidable case (alpha=0). Numerical experiments are performed for the
specific set up envisaged for the JUNO project, assuming a realistic sample of
O(10^5) reactor events. We find a typical sensitivity of ~2 sigma to the
hierarchy in JUNO, which, however, can be challenged by energy scale and
spectrum shape systematics, whose possible conspiracy effects are investigated.
The prospective accuracy reachable for the other mass-mixing parameters is also
discussed.


title: Rigidity of equality cases in Steiner's perimeter inequality

abstract:
  Characterization results for equality cases and for rigidity of equality
cases in Steiner's perimeter inequality are presented. (By rigidity, we mean
the situation when all equality cases are vertical translations of the
Steiner's symmetral under consideration.) We achieve this through the
introduction of a suitable measure-theoretic notion of connectedness and a fine
analysis of barycenter functions for sets of finite perimeter having segments
as orthogonal sections with respect to an hyperplane.


title: Towards a Software Product Sustainability Model

abstract:
  The necessity to adapt current products and services into a way of working
environmentally friendly is already a social and economic demand. Although the
GreenIT can be considered a mature discipline, software sustainability, both in
its process and its use, has not begun to be a topic of interest until the last
few years. In this sense we think is fundamental to define what we consider
that is software sustainability and how to evaluate it properly.


title:
Influence of the spreading resistance on the conductance spectrum of
  planar hybrid thin film SNS' junctions based on iron pnictides

abstract:
  To investigate the superconducting properties of iron pnictides we prepared
planar hybrid SNS' junctions in thin film technology with a pnictide base
electrode, a gold barrier layer and a lead counter electrode. Our design allows
characterization of the electrodes and the junction independently in a 4-probe
method. We show how both electrodes influence the measured spectra due to their
spreading resistance. While the Pb electrode has a constant resistance above
its $T_c$, the contribution of the pnictide electrode is clearly
current-dependent and thus it needs a more advanced method to be corrected. We
present an empirical method, which is simple to apply and allows to deal with
the spreading resistance in our junctions to recalculate the actual conductance
and voltage of one junction at given temperature.


title:
Measurement of electrons from heavy-flavour hadron decays in pp and p-Pb
  collisions with ALICE

abstract:
  ALICE measured electrons from inclusive heavy-flavour hadron decays and
beauty-hadron decays at mid-rapidity in pp collisions at \sqrt{s} = 7 TeV and
2.76 TeV and p-Pb collisions at \sqrt{s_{NN}} = 5.02 TeV. For both pp collision
energies, p_T-differential electron production cross sections are presented and
compared to pQCD predictions. For p-Pb collisions, the p_T-dependent nuclear
modification factor of electrons from inclusive heavy-flavour hadron decays is
presented.


title: Three-loop beta-functions and anomalous dimensions in the Standard Model

abstract:
  In this talk the methods and computer tools which were used in our recent
calculation of the three-loop Standard Model renormalization group coefficients
are discussed. A brief review of the techniques based on special features of
dimensional regularization and minimal subtraction schemes is given. Our
treatment of gamma5 is presented in some details. In addition, for a reasonable
set of initial parameters the numerical estimates of the obtained three-loop
contributions are presented.


title: Power Efficient MISO Beamforming for Secure Layered Transmission

abstract:
  This paper studies secure layered video transmission in a multiuser
multiple-input single-output (MISO) beamforming downlink communication system.
The power allocation algorithm design is formulated as a non-convex
optimization problem for minimizing the total transmit power while guaranteeing
a minimum received signal-to-interference-plus-noise ratio (SINR) at the
desired receiver. In particular, the proposed problem formulation takes into
account the self-protecting architecture of layered transmission and artificial
noise generation to prevent potential information eavesdropping. A
semi-definite programming (SDP) relaxation based power allocation algorithm is
proposed to obtain an upper bound solution. A sufficient condition for the
global optimal solution is examined to reveal the tightness of the upper bound
solution. Subsequently, two suboptimal power allocation schemes with low
computational complexity are proposed for enabling secure layered video
transmission. Simulation results demonstrate significant transmit power savings
achieved by the proposed algorithms and layered transmission compared to the
baseline schemes.


title: Fast ranking algorithm for very large data

abstract:
  In this paper, we propose a new ranking method inspired from previous results
on the diffusion approach to solve linear equation. We describe new
mathematical equations corresponding to this method and show through
experimental results the potential computational gain. This ranking method is
also compared to the well known PageRank model.


title:
The connection between the cusp-to-core transformation and observational
  universalities of DM halos

abstract:
  Observations have revealed interesting universal properties of dark matter
(DM) halos especially around low-mass galaxies. Strigari et al. (2008) showed
that DM halos have common enclosed masses within 300pc (Strigari relation).
Kormendy & Freeman (2004) reported DM halos having almost identical central
surface densities (the $\mu_{\rm 0D}$ relation). In addition, there exists a
core-cusp problem, a discrepancy of the central density distribution between
simulated halos and observations. We investigate whether a scenario where cuspy
halos transform into cores by some dynamical processes can also explain their
universal structural properties. It is shown that a cusp-to-core transformation
model naturally reproduces the $\mu_{\rm 0D}$ relation and that Strigari
relation follows from the $\mu_{\rm 0D}$ relation for dwarf galaxies. We also
show that the central densities of cored dark halos provide valuable
information about their formation redshifts.


title:
Comprehensive Unified Models of Structural and Reduced Form Models for
  Defaultable Fixed Income Bonds (Part 1: One factor-model, Part 2:Two
  factors-model)

abstract:
  Pricing formulae for defaultable corporate bonds with discrete coupons under
consideration of the government taxes in the united model of structural and
reduced form models are provided. The aim of this paper is to generalize the
comprehensive structural model for defaultable fixed income bonds (considered
in [1]) into a comprehensive unified model of structural and reduced form
models. Here we consider the one factor model and the two factor model. In the
one factor model the bond holders receive the deterministic coupon at
predetermined coupon dates and the face value (debt) and the coupon at the
maturity as well as the effect of government taxes which are paid on the
proceeds of an investment in bonds is considered under constant short rate. In
the two factor model the bond holders receive the stochastic coupon (discounted
value of that at the maturity) at predetermined coupon dates and the face value
(debt) and the coupon at the maturity as well as the effect of government taxes
which are paid on the proceeds of an investment in bonds is considered under
stochastic short rate. The expected default event occurs when the equity value
is not enough to pay coupon or debt at the coupon dates or maturity and
unexpected default event can occur at the first jump time of a Poisson process
with the given default intensity provided by a step function of time variable.
We consider the model and pricing formula for equity value and using it
calculate expected default barrier. Then we provide pricing model and formula
for defaultable corporate bonds with discrete coupons and consider its duration
and the effect of the government taxes.


title: Gamma-ray generation in ultrahigh-intensity laser-foil interactions

abstract:
  Incoherent photon emission by ultrarelativistic electrons in the normal
incidence of a laser pulse on a foil is investigated by means of
three-dimensional numerical simulations in the range of intensities $2 \times
10^{21} \text{--} 2 \times 10^{25} \text{W} \, \text{cm}^{-2}$ and electron
densities $2 \times 10^{22} \text{--} 1 \times 10^{24} \text{cm}^{-3}$. We
focus on properties of the resulting synchrotron radiation, such as its overall
energy, directivity of the radiation pattern and slope of the energy spectrum.
Regimes of laser-foil interactions are studied in the framework of a simple
analytical model. The laser-plasma parameters for efficient gamma-ray
generation are found and revealed to be close to the parameters for
relativistic foil motion. It is shown that in the case of oblique incidence of
a $3 \text{PW}$, $10 \text{fs}$ laser pulse on a thin foil about $10^{8}
\text{photons}/0.1\% \text{bandwidth}$ are produced at the energy level of $1
\text{MeV}$ that significantly exceeds performance of the modern Compton
gamma-ray sources. Various applications of the gamma-ray bunches are discussed.


title:
Preparing Korean Data for the Shared Task on Parsing Morphologically
  Rich Languages

abstract:
  This document gives a brief description of Korean data prepared for the SPMRL
2013 shared task. A total of 27,363 sentences with 350,090 tokens are used for
the shared task. All constituent trees are collected from the KAIST Treebank
and transformed to the Penn Treebank style. All dependency trees are converted
from the transformed constituent trees using heuristics and labeling rules de-
signed specifically for the KAIST Treebank. In addition to the gold-standard
morphological analysis provided by the KAIST Treebank, two sets of automatic
morphological analysis are provided for the shared task, one is generated by
the HanNanum morphological analyzer, and the other is generated by the Sejong
morphological analyzer.


title:
Search for a correlation between giant radio pulses and hard X-ray
  emissions in the Crab pulsar

abstract:
  We present the results of the search for a correlation between giant radio
pulses (GRPs) at 1.4 GHz and hard X-rays at 15-75 keV from the Crab pulsar. We
made simultaneous ground and satellite observations of the Crab pulsar over 12
hours in three occasions in April 2010, March and September 2011, and got a
sample of 1.3*10^4 main-pulse phase GRPs. From these samples we have found
statistically marginal enhancement (21.5%, 2.70 sigma) of hard X-ray flux
within +/- 1.5 degree phase angle of the synchronous peak of main-pulse phase
GRPs. This enhancement, if confirmed, implicates that GRPs may accompany plasma
density increases in the pulsar magnetosphere.


title: Centers of Generalized Quantum Groups

abstract:
  This paper treats the generalized quantum group $U=U(\chi,\pi)$ with a
bi-homomorphism $\chi$ for which the corresponding generalized root system is a
finite set. We establish a Harish-Chandra type theorem describing the (skew)
center of $U$.


title:
Can parity-time-symmetric potentials support continuous families of
  non-parity-time-symmetric solitons?

abstract:
  For the one-dimensional nonlinear Schroedinger equations with parity-time
(PT) symmetric potentials, it is shown that when a real symmetric potential is
perturbed by weak PT-symmetric perturbations, continuous families of asymmetric
solitary waves in the real potential are destroyed. It is also shown that in
the same model with a general PT-symmetric potential, symmetry breaking of
PT-symmetric solitary waves do not occur. Based on these findings, it is
conjectured that one-dimensional PT-symmetric potentials cannot support
continuous families of non-PT-symmetric solitary waves.


title: Two-photon spectroscopy of trapped HD$^+$ ions in the Lamb-Dicke regime

abstract:
  We study the feasibility of nearly-degenerate two-photon rovibrational
spectroscopy in ensembles of trapped, sympathetically cooled hydrogen molecular
ions using a resonance-enhanced multiphoton dissociation (REMPD) scheme. Taking
advantage of quasi-coincidences in the rovibrational spectrum, the excitation
lasers are tuned close to an intermediate level to resonantly enhance
two-photon absorption. Realistic simulations of the REMPD signal are obtained
using a four-level model that takes into account saturation effects, ion
trajectories, laser frequency noise and redistribution of population by
blackbody radiation. We show that the use of counterpropagating laser beams
enables optical excitation in an effective Lamb-Dicke regime. Sub-Doppler lines
having widths in the 100 Hz range can be observed with good signal-to-noise
ratio for an optimal choice of laser detunings. Our results indicate the
feasibility of molecular spectroscopy at the $10^{-14}$ accuracy level for
improved tests of molecular QED, a new determination of the proton-to-electron
mass ratio, and studies of the time (in)dependence of the latter.


title:
A Generic Approach to Solving Jump Diffusion Equations with Applications
  to Neural Populations

abstract:
  Diffusion processes have been applied with great success to model the
dynamics of large populations throughout science, in particular biology. One
advantage is that they bridge two different scales: the microscopic and the
macroscopic one. Diffusion is a mathematical idealisation, however: it assumes
vanishingly small state changes at the microscopic level. In real biological
systems this is often not the case. The differential Chapman-Kolmogorov
equation is more appropriate to model population dynamics that is not well
described by drift and diffusion alone.
  Here, the method of characteristics is used to transform deterministic
dynamics away and find a coordinate frame where this equation reduces to a
Master equation. There is no longer a drift term, and solution methods there
are insensitive to density gradients, making the method suitable for jump
processes with arbitrary jump sizes. Moreover, its solution is universal: it no
longer depends explicitly on the deterministic system.
  We demonstrate the technique on simple models of neuronal populations.
Surprisingly, it is suitable for fast neural dynamics, even though in the new
coordinate frame state space may expand rapidly towards infinity. We
demonstrate universality: the method is applicable to any one dimensional
neural model and show this on populations of leaky- and
quadratic-integrate-and-fire neurons. In the diffusive limit, excellent
approximations of Fokker-Planck equations are achieved. Nothing in the approach
is particular to neuroscience, and the neural models are simple enough to serve
as an example of dynamical systems that demonstrates the method.


title: On the Dipole Approximation with Error Estimates

abstract:
  The dipole approximation is employed to describe interactions between atoms
and radiation. It essentially consists of neglecting the spatial variation of
the external field over the atom. Heuristically, this is justified by arguing
that the wavelength is considerably larger than the atomic length scale, which
holds under usual experimental conditions. We prove the dipole approximation in
the limit of infinite wavelengths compared to the atomic length scale and
estimate the rate of convergence. Our results include N-body Coulomb potentials
and experimentally relevant electromagnetic fields such as plane waves and
laser pulses.


title: Matrix-valued Quantum Lattice Boltzmann Method

abstract:
  We devise a lattice Boltzmann method (LBM) for a matrix-valued quantum
Boltzmann equation, with the classical Maxwell distribution replaced by
Fermi-Dirac functions. To accommodate the spin density matrix, the distribution
functions become 2 x 2 matrix-valued. From an analytic perspective, the
efficient, commonly used BGK approximation of the collision operator is valid
in the present setting. The numerical scheme could leverage the principles of
LBM for simulating complex spin systems, with applications to spintronics.

categories: physics.comp-ph cs.NA physics.flu-dyn quant-ph


title:
Influence of multiple in-medium scattering processes on the momentum
  imbalance of reconstructed di-jets

abstract:
  Experimental data measured in sqrt(s)=2.76 TeV Pb+Pb collisions at the LHC
show a significant enhancement of events with an unbalanced pair of
reconstructed jet momenta in comparison with p+p collisions. This enhancement
of momentum imbalance is supposed to be caused by the different momentum loss
of the initial back-to-back di-partons by scatterings within the created dense
medium. For investigating the underlying partonic momentum loss we employ the
on-shell transport model BAMPS (Boltzmann Approach for Multi-Parton Scattering)
for full heavy-ion collisions, which numerically solves the 3+1D Boltzmann
equation based on 2->2 as well as inelastic 2<->3 scattering processes,
together with PYTHIA initial state conditions for the parton showers. Due to
the employed test-particle approach jet reconstruction within BAMPS events is
not trivial. We introduce a method that nevertheless allows the microscopic
simulation of the full evolution of the shower particles, recoiled medium
particles, and the underlying bulk medium in one common microscopic framework.
With this method it is possible to investigate the role of the medium recoil
for the momentum imbalance A_J while using well-established background
subtraction algorithms. Due to the available particle information in
configuration as well as momentum space within BAMPS, it is additionally
possible to reproduce the entire evolution of the reconstructed jets within the
medium. With this information we investigate the sensitivity of the jet
momentum loss from the difference in the partonic in-medium path lengths.


title:
The Breuil-Mezard conjecture for non-scalar split residual
  representations

abstract:
  We prove the Breuil-Mezard conjecture for split non-scalar residual
representations of Gal(Qp/Qp) by local methods. Combined with the cases
previously proved in [18] and [24], this completes the proof of the conjecture
(when p>3). As a consequence, the local restriction in the proof of the
Fontaine-Mazur conjecture in [18] is removed.


title: Partial Representations of Hopf Algebras

abstract:
  In this work, the notion of partial representation of a Hopf algebra is
introduced and its relationship with partial actions of Hopf algebras is
explored. Given a Hopf algebra $H$, one can associate it to a Hopf algebroid
$H_{par}$ which has the universal property that each partial representation of
$H$ can be factorized by an algebra morphism from $H_{par}$. We define also the
category of partial modules over a Hopf algebra $H$, which is the category of
modules over its associated Hopf algebroid $H_{par}$. The Hopf algebroid
structure of $H_{par}$ enables us to enhance the category of partial $H$
modules with a monoidal structure and such that the algebra objects in this
category are the usual partial actions. Some examples of categories of partial
$H$ modules are explored. In particular we can describe fully the category of
partially $\mathbb{Z}_2$-graded modules.


title: Gauge gravity and discrete quantum models

abstract:
  The gauge gravity action for general relativity in any dimension using a
connection for the Euclidean or Poincar\'e group and a symmetry-breaking scalar
field is written using a particularly simple matrix technique. A discrete
version of the gauge gravity action for variables on a triangulated 3-manifold
is given and it is shown how, for a certain class of triangulations of the
three-sphere, the discrete quantum model this defines is equivalent to the
Ponzano-Regge model of quantum gravity.


title: Adams operations and Galois structure

abstract:
  We present a new method for determining the Galois module structure of the
cohomology of coherent sheaves on varieties over the integers with a tame
action of a finite group. This uses a novel Adams-Riemann-Roch type theorem
obtained by combining the Kunneth formula with localization in equivariant
K-theory and classical results about cyclotomic fields. As an application, we
show two conjectures of Chinburg-Pappas-Taylor, in the case of curves.


title: Quantitative modeling of degree-degree correlation in complex networks

abstract:
  This paper presents an approach to the modeling of degree-degree correlation
in complex networks. Thus, a simple function, \Delta(k', k), describing
specific degree-to- degree correlations is considered. The function is well
suited to graphically depict assortative and disassortative variations within
networks. To quantify degree correlation variations, the joint probability
distribution between nodes with arbitrary degrees, P(k', k), is used.
Introduction of the end-degree probability function as a basic variable allows
using group theory to derive mathematical models for P(k', k). In this form, an
expression, representing a family of seven models, is constructed with the
needed normalization conditions. Applied to \Delta(k', k), this expression
predicts a nonuniform distribution of degree correlation in networks, organized
in two assortative and two disassortative zones. This structure is actually
observed in a set of four modeled, technological, social, and biological
networks. A regression study performed on 15 actual networks shows that the
model describes quantitatively degree-degree correlation variations.


title:
Analysis of chemical abundances in planetary nebulae with [WC] central
  stars. II. Chemical abundances and the abundance discrepancy factor

abstract:
  (Abridged) We present the abundance analysis of 12 PNe ionized by [WC]-type
stars and wels obtained from high-resolution spectrophotometric data. Our main
aims are to determine the chemical composition of the PNe and to study the
behaviour of the abundance discrepancy problem (ADF) in this type of planetary
nebulae. The detection of a large number of optical recombination lines (ORLs)
and collisionally excited lines (CELs) from different ions were presented
previously. Most of the ORLs were reported for the first time in these PNe.
Ionic abundances were derived from the available CELs and ORLs, using
previously determined physical conditions. Based on these two sets of ionic
abundances, we derived the total chemical abundances in the nebulae using
suitable ICFs (when available). In spite of the [WC] nature of the central
stars, moderate ADF(O^++), in the range from 1.2 to 4, were found for all the
objects. We found that when the quality of the spectra is high enough the ORLs
O^++/H^+ abundance ratios obtained from different multiplets excited mainly by
recombination are very similar. Possible dependence of ADFs with some nebular
characteristics were analysed, finding no correlation. Abundances derived from
CELs were corrected by determining the t^2 parameter. O abundances for PNe,
derived from ORLs, are in general larger than the solar abundance. We derived
the C/O ratio from ORLs and N/O and alpha-element/O ratios from CELs and found
that these PNe are, in average, N-and C-richer than the average of large PN
samples. About half of our sample is C-rich (C/O>1). The alpha-elements grow in
lockstep with O abundance. Comparing the N/O and C /O ratios with those derived
from stellar evolution models, we estimate that about half of our PNe have
progenitors with initial masses > 4 M_sun. No correlation was found between the
stellar [WC]-type and the nebular abundances.


title:
Algorithmic framework for group analysis of differential equations and
  its application to generalized Zakharov--Kuznetsov equations

abstract:
  In this paper, we explain in more details the modern treatment of the problem
of group classification of (systems of) partial differential equations (PDEs)
from the algorithmic point of view. More precisely, we revise the classical
Lie--Ovsiannikov algorithm of construction of symmetries of differential
equations, describe the group classification algorithm and discuss the process
of reduction of (systems of) PDEs to (systems of) equations with smaller number
of independent variables in order to construct invariant solutions. The group
classification algorithm and reduction process are illustrated by the example
of the generalized Zakharov--Kuznetsov (GZK) equations of form
$u_t+(F(u))_{xxx}+(G(u))_{xyy}+(H(u))_x=0$. As a result, a complete group
classification of the GZK equations is performed and a number of new
interesting nonlinear invariant models which have non-trivial invariance
algebras are obtained. Lie symmetry reductions and exact solutions for two
important invariant models, i.e., the classical and modified
Zakharov--Kuznetsov equations, are constructed. The algorithmic framework for
group analysis of differential equations presented in this paper can also be
applied to other nonlinear PDEs.


title:
Testing the higgsino-singlino sector of the NMSSM with trileptons at the
  LHC

abstract:
  We propose a simplified light higgsino-singlino scenario in the NMSSM, in
which the masses of the chargino and the lightest neutralino determine the
masses and couplings of all 3 lightest neutralinos. This scenario is
complementary to the simplified wino-like chargino/neutralino scenario used
conventionally for the interpretation of results from trilepton searches, and
motivated by lower bounds on the gluino mass in the case of GUT relations
between the wino and gluino masses. We present all masses and mixing angles
necessary for the determination of production cross sections of the chargino
and the 3 neutralinos in the form of Tables in the M_{neutralino_1} -
M_{chargino_1} plane, assuming Higgs mass motivated values for tan(beta)=2 and
lambda=0.6. We show that this scenario leads to considerable signal rates, and
present constraints in this plane from recent searches for trileptons at the
LHC.


title:
One, two or three stars? An investigation of an unusual eclipsing binary
  candidate undergoing dramatic period changes

abstract:
  We report our investigation of 1SWASP J234401.81-212229.1, a variable with a
18461.6 s period. After identification in a 2011 search of the SuperWASP
archive for main-sequence eclipsing binary candidates near the distribution's
short-period limit of approx. 0.20 d, it was measured to be undergoing rapid
period decrease in our earlier work, though later observations supported a
cyclic variation in period length. Spectroscopic data obtained in 2012 with the
Southern African Large Telescope did not, however, support the interpretation
of the object as a normal eclipsing binary. Here, we consider three possible
explanations consistent with the data: a single-star oblique rotator model in
which variability results from stable cool spots on opposite magnetic poles; a
two-star model in which the secondary is a brown dwarf; and a three-star model
involving a low-mass eclipsing binary in a hierarchical triple system. We
conclude that the latter is the most likely model.


title: Topological crystalline insulator phase in graphene multilayers

abstract:
  While the experimental progress on three dimensional topological insulators
is rapid, the development of their two dimensional counterparts has been
comparatively slow, despite their technological promise. The main reason is
materials challenges of the to date only realizations of two-dimensional
topological insulators, in semiconductor quantum wells. Here we identify a two
dimensional topological insulator in a material which does not face similar
challenges and which is by now most widely available and well-charaterized:
graphene. For certain commensurate interlayer twists graphene multilayers are
insulators with sizable bandgaps. We show that they are moreover in a
topological phase protected by crystal symmetry. As its fundamental signature,
this topological state supports one-dimensional boundary modes. They form
low-dissipation quantum wires that can be defined purely electrostatically.


title: Dynamical quantum repeater using cavity-QED and optical coherent states

abstract:
  In the framework of cavity QED, we propose a quantum repeater scheme that
uses coherent light and atoms coupled to optical cavities. In contrast to
conventional schemes, we exploit solely the cavity QED evolution for the entire
quantum repeater scheme and, thus, avoid any explicit execution of quantum
logical gates. The entanglement distribution between the repeater nodes is
realized with the help of pulses of coherent light interacting with the
atom-cavity system in each repeater node. In our previous paper [D. Gonta and
P. van Loock, Phys. Rev. A 86, 052312 (2012)], we already proposed a dynamical
protocol to purify a bipartite entangled state using the evolution of atomic
chains coupled to optical cavities. Here, we incorporate parts of this protocol
in our repeater scheme, combining it with dynamical versions of entanglement
distribution and swapping.


title: Unveiling new members in five nearby young moving groups

abstract:
  In the last decade many kinematic groups of young stars (<100 Myr) were
discovered in the solar neighbourhood. Since the most interesting period of
planet formation overlaps with the age of these groups, their well dated
members are attractive targets for exoplanet searches by direct imaging. We
combined astrometric, photometric and X-ray data, and applied strict selection
criteria to explore the stellar content of five nearby moving groups. We
identified more than 100 potential new candidate members in the {\ss} Pic
moving group, and in the Tucana-Horologium, Columba, Carina, and Argus
associations. In order to further assess and confirm their membership status,
we analysed radial velocity data and lithium equivalent widths extracted from
high-resolution spectra of 54 candidate stars. We identified 35 new
probable/possible young moving group members: 4 in the {\ss} Pic moving group,
11 in the Columba association, 16 in the Carina association, and 4 in the Argus
association. We found serendipitiously a new AB Dor moving group member as
well. For four Columba systems Hipparcos based parallaxes have already been
available and as they are consistent with the predicted kinematic parallaxes,
they can be considered as secure new members.


title: Scalar masses in general N=2 gauged supergravity theories

abstract:
  We readdress the question of whether any universal upper bound exists on the
square mass m^2 of the lightest scalar around a supersymmetry breaking vacuum
in generic N=2 gauged supergravity theories for a given gravitino mass m_3/2
and cosmological constant V. We review the known bounds which apply to theories
with restricted matter content from a new perspective. We then extend these
results to theories with both hyper and vector multiplets and a gauging
involving only one generator, for which we show that such a bound exists for
both V>0 and V<0. We finally argue that there is no bound for the same theories
with a gauging involving two or more generators. These results imply that in
N=2 supergravity theories metastable de Sitter vacua with V<<m^2_3/2 can only
arise if at least two isometries are gauged, while those with V>>m^2_3/2 can
also arise when a single isometry is gauged.


title: The Unusual Kuiper Belt Object 2003 SQ317

abstract:
  We report photometric observations of Kuiper belt object 2013 SQ317 obtained
between 2011 August 21 and 2011 November 1 at the 3.58 m New Technology
Telescope, La Silla. We obtained a rotational lightcurve for 2013 SQ317 with a
large peak-to-peak photometric range 0.85+/-0.05 mag, and a periodicity,
P=7.210+/-0.001 hr. We also measure a nearly neutral broadband colour
B-R=1.05+/-0.18 mag and a phase function with slope beta=0.95+/-0.41 mag/deg.
The large lightcurve range implies an extremely elongated shape for 2013 SQ317,
possibly as a single elongated object but most simply explained as a compact
binary. If modelled as a compact binary near hydrostatic equilibrium, the bulk
density of 2013 SQ317 is near 2670 kg m^(-3). If 2003 SQ317 is instead a
single, elongated object, then its equilibrium density is about 860 kg m^(-3).
These density estimates become uncertain at the 30% level if we relax the
hydrostatic assumption and account for solid, "rubble pile"-type
configurations. 2013 SQ317 has been associated with the Haumea family based on
its orbital parameters and near-infrared colour; we discuss our findings in
this context. If confirmed as a close binary, 2013 SQ317 will be the second
object of its kind identified in the Kuiper belt.


title: Condensate Phase Microscopy

abstract:
  We show that the phase of a Bose-Einstein condensate wave-function of
ultra-cold atoms in an optical lattice potential in two-dimensions can be
detected. The time-of-flight images, obtained in a free expansion of initially
trapped atoms, are related to the initial distribution of atomic momenta but
the information on the phase is lost. However, the initial atomic cloud is
bounded and this information, in addition to the time-of-flight images, is
sufficient in order to employ the phase retrieval algorithms. We analyze the
phase retrieval methods for model wave-functions in a case of a Bose-Einstein
condensate in a triangular optical lattice in the presence of artificial gauge
fields.


title:
Dynamical phase transitions, time-integrated observables and geometry of
  states

abstract:
  We show that there exist dynamical phase transitions (DPTs), as defined in
[Phys. Rev. Lett. 110 135704 (2013)], in the transverse-field Ising model
(TFIM) away from the static quantum critical points. We study a class of
special states associated with singularities in the generating functions of
time-integrated observables found in [Phys. Rev. B 88 184303 (2013)]. Studying
the dynamics of these special states under the evolution of the TFIM
Hamiltonian, we find temporal non-analtyicities in the initial-state return
probability associated with dynamical phase transitions. By calculating the
Berry phase and Chern number we show the set of special states have interesting
geometric features similar to those associated with static quantum critical
points.


title:
A family of [[6k, 2k, 2]] codes for practical, scalable adiabatic
  quantum computation

abstract:
  In this work, we introduce a new family of [[6k, 2k, 2]] codes designed
specifically to be compatible with adiabatic quantum computation. These codes
support computationally universal sets of weight-two logical operators and are
particularly well-suited for implementing dynamical decoupling error
suppression. For Hamiltonians embeddable on a planar graph of fixed degree, our
encoding maintains a planar connectivity graph and increase the graph degree by
only two. These codes are the first known to possess these features.


title: A resolved debris disk around the candidate planet-hosting star HD95086

abstract:
  Recently, a new planet candidate was discovered on direct images around the
young (10-17 Myr) A-type star HD95086. The strong infrared excess of the system
indicates that, similarly to HR8799, {\ss} Pic, and Fomalhaut, the star harbors
a circumstellar disk. Aiming to study the structure and gas content of the
HD95086 disk, and to investigate its possible interaction with the newly
discovered planet, here we present new optical, infrared and millimeter
observations. We detected no CO emission, excluding the possibility of an
evolved gaseous primordial disk. Simple blackbody modeling of the spectral
energy distribution suggests the presence of two spatially separate dust belts
at radial distances of 6 and 64 AU. Our resolved images obtained with the
Herschel Space Observatory reveal a characteristic disk size of ~6.0x5.4 arcsec
(540x490 AU) and disk inclination of ~25 degree. Assuming the same inclination
for the planet candidate's orbit, its re-projected radial distance from the
star is 62 AU, very close to the blackbody radius of the outer cold dust ring.
The structure of the planetary system at HD95086 resembles the one around
HR8799. Both systems harbor a warm inner dust belt and a broad colder outer
disk and giant planet(s) between the two dusty regions. Modelling implies that
the candidate planet can dynamically excite the motion of planetesimals even
out to 270 AU via their secular perturbation if its orbital eccentricity is
larger than about 0.4. Our analysis adds a new example to the three known
systems where directly imaged planet(s) and debris disks co-exist.


title: Yangian Symmetry of smooth Wilson Loops in N=4 super Yang-Mills Theory

abstract:
  We show that appropriately supersymmetrized smooth Maldacena-Wilson loop
operators in N=4 super Yang-Mills theory are invariant under a Yangian symmetry
Y[psu(2,2|4)] built upon the manifest superconformal symmetry algebra of the
theory. The existence of this hidden symmetry is demonstrated at the one-loop
order in the weak coupling limit as well as at leading order in the strong
coupling limit employing the classical integrability of the dual AdS_5 x S^5
string description. The hidden symmetry generators consist of a canonical
non-local second order variational derivative piece acting on the superpath,
along with a novel local path dependent contribution. We match the functional
form of these Yangian symmetry generators at weak and strong coupling and find
evidence for an interpolating function. Our findings represent the smooth
counterpart to the Yangian invariance of scattering superamplitudes dual to
light-like polygonal super Wilson loops in the N=4 super Yang-Mills theory.


title: Toward a Research Software Security Maturity Model

abstract:
  In its Vision and Strategy for Software for Science, Engineering, and
Education the NSF states that it will invest in activities that: "Recognize
that software strategies must include the secure and reliable deployment and
operation of services, for example by campuses or national facilities or
industry, where identity, authentication, authorization and assurance are
crucial operational capabilities." and "Result in high-quality, usable, secure,
vulnerability-free, sustainable, robust, well-tested, and
maintainable/evolvable software; and which promotes the sustainability of solid
and useful on-going investments."
  Such statements evidence that security should indeed be a first-class
consideration of the software ecosystem. In this position paper, we share some
thoughts related to research software security. Our thoughts are based on the
observation that security is not a binary, all-or-nothing attribute, but a
range of practices and requirements depending on how the software is expected
to be deployed and used. We propose that the community leverage the concept of
a maturity model, and work to agree on a research software security maturity
model. This model would categorize different sets of security needs of the
deployment community, and provide software developers a roadmap for advancing
the security maturity of their software. The intent of this paper is not to
express such a comprehensive maturity model, but instead to start a
conversation and set some initial requirements.


title: Augmented Biracks and their Homology

abstract:
  We introduce augmented biracks and define a (co)homology theory associated to
augmented biracks. The new homology theory extends the previously studied
Yang-Baxter homology with a combinatorial formulation for the boundary map and
specializes to $N$-reduced rack homology when the birack is a rack. We
introduce augmented birack 2-cocycle invariants of classical and virtual knots
and links and provide examples.


title: Some new problems in additive combinatorics

abstract:
  In this paper we investigate some new problems in additive combinatorics. Our
problems mainly involve permutations (or circular permutations) $n$ distinct
numbers (or elements of an additive abelian group) $a_1,\ldots,a_n$ with
adjacent sums $a_i+a_{i+1}$ (or differences $a_i-a_{i+1}$) pairwise distinct.
For an odd prime power $q=2n+1>13$ with $q\not=25$, we show that there is a
circular permutation $(a_1,\ldots,a_n)$ of the elements of $S=\{a^2:\
a\in\mathbb F_q\setminus\{0\}\}$ such that
$\{a_1+a_2,\ldots,a_{n-1}+a_n,a_n+a_1\}=S$, where $\mathbb F_q$ denotes the
field of order $q$. For any finite subset $A$ of an additive torsion-free
abelian group $G$ with $|A|=n>3$, we prove that there is a numbering
$a_1,\ldots,a_n$ of the elements of $A$ such that $$a_1+2a_2,\ a_2+2a_3,\
\ldots,\ a_{n-1}+2a_n,\ a_n+2a_1$$ are pairwise distinct. We also pose 30 open
conjectures for further research.


title: Constructing Ordered Orthogonal Arrays via Sudoku

abstract:
  For prime powers q we use "strongly orthogonal" linear Sudoku solutions of
order q^2 to construct ordered orthogonal arrays of type OOA (4,s,2,q), and for
each q we present a range of values of s for which these constructions are
valid.


title: Y(4260) and Y(4360) as mixed hadrocharmonium

abstract:
  Recent BESIII data indicate a significant rate of the process $e^+e^- \to h_c
\pi^+ \pi^-$ at the Y(4260) and Y(4360) resonances, implying a substantial
breaking of the heavy quark spin symmetry. We consider these resonances within
the picture of hadrocharmonium, i.e. of (relatively) compact charmonium
embedded in a light quark mesonic excitation. We suggest that the resonances
Y(4260) and Y(4360) are a mixture, with mixing close to maximal, of two states
of hadrochamonium, one containing a spin-triplet $c \bar c$ pair and the other
containing a spin-singlet heavy quark pair. We argue that this model is in a
reasonable agreement with the available data and produces distinctive and
verifiable predictions for the energy dependence of the production rate in
$e^+e^-$ annihilation of the final states $J/\psi \pi \pi$, $\psi' \pi \pi$ and
$h_c \pi \pi$, including the pattern of interference between the two
resonances.


title:
A Comparison of Continuous and Stochastic Methods for Modeling Rain Drop
  Growth in Clouds

abstract:
  Two models for raindrop growth in clouds are developed and compared. A
continuous accretion model is solved numerically for drop growth from 20-50
microns, using a polynomial approximation to the collection kernel, and is
shown to underestimate growth rates. A Monte Carlo simulation for stochastic
growth is also implemented to demonstrate discrete drop growth. The approach
models the effect of decreased average time between captures as the drop size
increases. It is found that the stochastic model yields a more realistic growth
rate, especially for larger drop sizes. It is concluded that the stochastic
model showed faster droplet accumulation and hence shorter times for drop
growth.


title:
Renormalization of the strongly attractive inverse square potential:
  Taming the singularity

abstract:
  Quantum anomalies in the inverse square potential are well known and widely
investigated. Most prominent is the unbounded increase in oscillations of the
particle's state as it approaches the origin when the attractive coupling
parameter is greater than the critical value of 1/4. Due to this unphysical
divergence in oscillations, we are proposing that the interaction gets screened
at short distances making the coupling parameter acquire an effective
(renormalized) value that falls within the weak range 0 to 1/4. This prevents
the oscillations form growing without limit giving a lower bound to the energy
spectrum and forcing the Hamiltonian of the system to be self-adjoint.
Technically, this translates into a regularization scheme whereby the inverse
square potential is replaced near the origin by another that has the same
singularity but with a weak coupling strength. Here, we take the Eckart as the
regularizing potential and obtain the corresponding solutions (discrete bound
states and continuum scattering states).


title:
Probing the origin of the iron K_alpha line around stellar and
  supermassive black holes using X-ray polarimetry

abstract:
  Asymmetric, broad iron lines are a common feature in the X-ray spectra of
both X-ray binaries (XRBs) and type-1 Active Galactic Nuclei (AGN). It was
suggested that the distortion of the Fe K_alpha emission results from Doppler
and relativistic effects affecting the radiative transfer close to the strong
gravitational well of the central compact object: a stellar mass black hole
(BH) or neutron star (NS) in the case of XRBs, or a super massive black hole
(SMBH) in the case of AGN. However, alternative approaches based on
reprocessing and transmission of radiation through surrounding media also
attempt to explain the line broadening. So far, spectroscopic and timing
analyzes have not yet convinced the whole community to discriminate between the
two scenarios. Here we study to which extent X-ray polarimetric measurements of
black hole X-ray binaries (BHXRBs) and type-1 AGN could help to identify the
possible origin of the line distortion. To do so, we report on recent
simulations obtained for the two BH flavors and show that the proposed
scenarios are found to behave differently in polarization degree and
polarization angle. A relativistic origin for the distortion is found to be
more probable in the context of BHXRBs, supporting the idea that the same
mechanism should lead the way also for AGN. We show that the discriminating
polarization signal could have been detectable by several X-ray polarimetry
missions proposed in the past.


title: Effective potential and geodesic motion in Kerr-de Sitter space-time

abstract:
  In the present work, geodesic trajectories in Kerr-de Sitter geometry is
analyzed. From the mathematical solution of Lagrangian formalism appropriate to
motions in the equatorial plane (for which 'theta' = 0 and 'theta' =
(constant)= pi/2) can give potential energy of massive and massless particles
for rotating axisymetric black hole. From this, for a particular value of
cosmological constant, Kerr parameter, mass, angular momentum and impact
parameter; variation of potential with distance can be found. Similarly, for a
particular value of cosmological constant, mass and Kerr parameter; variation
of velocity with distance can be found.


title:
The essential centre of the mod a diagonalization ideal commutant of an
  n-tuple of commuting hermitian operators

abstract:
  We show that for a commuting n-tuple of hermitian operators, with perfect
spectrum, the essential centre of the algebra of operators commuting with the
n-tuple mod a diagonalization ideal arises from the C*-algebra of the n-tuple.
This answers a question for normal operators and the Hilbert-Schmidt class
connected to K-theory for almost normal operators.


title: Gauge/Liouville Triality

abstract:
  Conformal blocks of Liouville theory have a Coulomb-gas representation as
Dotsenko-Fateev (DF) integrals over the positions of screening charges. For
q-deformed Liouville, the conformal blocks on a sphere with an arbitrary number
of punctures are manifestly the same, when written in DF representation, as the
partition functions of a class of 3d U(N) gauge theories with N=2
supersymmetry, in the Omega-background. Coupling the 3d gauge theory to a
flavor in fundamental representation corresponds to inserting a Liouville
vertex operator; the two real mass parameters determine the momentum and
position of the puncture. The DF integrals can be computed by residues. The
result is the instanton sum of a five dimensional N=1 gauge theory. The
positions of the poles are labeled by tuples of partitions, the residues of the
integrand are the Nekrasov summands.


title: Z' Discovery Reach at Future Hadron Colliders: A Snowmass White Paper

abstract:
  Extra neutral gauge bosons are a feature of many models of physics beyond the
standard model (BSM) and their discovery could possibly be the first evidence
for new physics. In this Snowmass white paper we compare the discovery reach of
the high energy hadron colliders considered by the Snowmass study for a broad
range of BSM models. It is expected that the LHC should be able to see evidence
for a Z' arising from a large variety of BSM models up to a mass of ~5 TeV when
the LHC reaches its design energy and luminosity, and up to ~6 TeV with the
high luminosity upgrade. Further into the future, the high energy LHC would
substantially extend this reach to ~11 TeV, while the ~100 TeV VHE-LHC could
see evidence for Z' 's up to ~30 TeV.


title: Dalitz-plot dependence of CP asymmetry in B+- --> K+- K+ K- decays

abstract:
  A large CP asymmetry predicted recently in the framework of the QCD
factorization model for the B+- --> K+- K+ K- decays in the range of the K+ K-
invariant masses above the phi(1020) resonance has been confirmed by the LHCb
Collaboration. We discuss the emergence and size of this asymmetry in an
extended model involving S- and P-waves together with the contribution from the
D-wave f2(1270) resonance and compare our model with the experimental data of
the LHCb and BABAR Collaborations.


title:
Continuum limit in matrix models for quantum gravity from the Functional
  Renormalization Group

abstract:
  We consider the double-scaling limit in matrix models for two-dimensional
quantum gravity, and establish the nonperturbative functional Renormalization
Group as a novel technique to compute the corresponding interacting fixed point
of the Renormalization Group flow. We explicitly evaluate critical exponents
and compare to the exact results. The functional Renormalization Group method
allows a generalization to tensor models for higher-dimensional quantum gravity
and to group field theories. As a simple example how this method works for such
models, we compute the leading-order beta function for a colored matrix model
that is inspired by recent developments in tensor models.


title:
Modelling the X-ray polarimetric signatures of complex geometry: the
  case study of the "changing look" AGN NGC 1365

abstract:
  "Changing look" Active Galactic Nuclei (AGN) are a subset of Seyfert galaxies
characterized by rapid transitions between Compton-thin and Compton-thick
regimes. In their Compton-thin state, the central engine is less obscured,
hence spectroscopy or timing observations can probe their innermost structures.
However, it is not clear if the observed emission features and the Compton hump
are associated with relativistic reflection onto the accretion disc, or complex
absorption by distant, absorbing gas clouds passing by the observer's
line-of-sight. Here, we investigate these two scenarios under the scope of
X-ray polarimetry, providing the first polarisation predictions for an
archetypal "changing look" AGN: NGC 1365. We explore the resulting polarisation
emerging from lamp-post emission and scattering off an accretion disc in the
immediate vicinity of a supermassive black hole. The computed polarisation
signatures are compared to the results of an absorption-dominated model, where
high column density gas partially covers the central source. While the shape of
the polarisation spectrum is similar, the two models differ in net polarisation
percentage, with the relativistic reflection scenario producing significantly
stronger polarisation. Additionally, the variation of the polarisation position
angle is distinctly different between both scenarios: the reflection-dominated
model produces smooth rotations of the polarisation angle with photon energy
whereas circumnuclear absorption causes an orthogonal switch of the
polarisation angle between the soft and the hard X-ray bands. By comparing the
predicted polarisation of NGC 1365 to the detectability levels of X-ray
polarimetry mission concepts proposed in the past, we demonstrate that with a
large, soft X-ray observatory or a medium-sized mission equipped with a hard (6
- 35 keV) polarimeter, the correct interpretation would be unambiguous.


title:
The Implementation of the Renormalized Complex MSSM in FeynArts and
  FormCalc

abstract:
  We describe the implementation of the renormalized complex MSSM (cMSSM) in
the diagram generator FeynArts and the calculational tool FormCalc. This
extension allows to perform UV-finite one-loop calculations of cMSSM processes
almost fully automatically. The Feynman rules for the cMSSM with counterterms
are available as a new model file for FeynArts. Also included are default
definitions of the renormalization constants; this fixes the renormalization
scheme. Beyond that all model parameters are generic, e.g. we do not impose any
relations to restrict the number of input parameters. The model file has been
tested extensively for several non-trivial decays and scattering reactions. Our
renormalization scheme has been shown to give stable results over large parts
of the cMSSM parameter space.


title: Darboux chart on Projective limit of weak symplectic Banach manifold

abstract:
  Suppose M be the projective limit of weak symplectic Banach manifolds
\{(M_i,\phi_{ij})\}_{i,j\in\mathbb N}, where M_i are modeled over reflexive
Banach space and \sigma is compatible with the inverse system(defined in the
article). We associate to each point x\in M, a Fr\'{e}chet space H_x(defined in
section 3). We prove that if H_x are locally constant, then with certain
smoothness and boundedness condition, there exists Darboux chart for the weak
symplectic structure.


title:
Global uniqueness in inverse boundary value problems for Navier-Stokes
  equations and Lam\'e system in two dimensions

abstract:
  We consider inverse boundary value problems for the Navier-Stokes equations
and the isotropic Lam\'e system in two dimensions. The uniqueness without any
smallness assumptions on unknown coefficients, which is called global
uniqueness, was longstanding open problems for the Navier-Stokes equations and
the isotropic Lam\'e system in two dimensions. We prove the global uniqueness
for both inverse boundary value problems. Our methodology are common for both
systems and the key is the construction of complex geometric optics solutions
after decoupling the systems into weakly coupling systems.


title: Coleman-Weinberg Inflation in light of Planck

abstract:
  We revisit a single field inflationary model based on Coleman-Weinberg
potentials. We show that in small field Coleman-Weinberg inflation, the
observed amplitude of perturbations needs an extremely small quartic coupling
of the inflaton, which might be a signature of radiative origin. However, the
spectral index obtained in a standard cosmological scenario turns out to be
outside the 2 sigma region of the Planck data. When a non-standard cosmological
framework is invoked, such as brane-world cosmology in the Randall-Sundrum
model, the spectral index can be made consistent with Planck data within 1
sigma, courtesy of the modification in the evolution of the Hubble parameter in
such a scheme. We also show that the required inflaton quartic coupling as well
as a phenomenologically viable B-L symmetry breaking together with a natural
electroweak symmetry breaking can arise dynamically in a generalized B-L
extension of the Standard Model where the full potential is assumed to vanish
at a high scale.


title:
Techniques of evaluation of QCD low-energy physical quantities with
  running coupling with infrared fixed point

abstract:
  Perturbative QCD (pQCD) running coupling a(Q^2) (=alpha_s(Q^2)/pi) is
expected to get modified at low spacelike momenta 0 < Q^2 < 1 GeV^2 so that,
instead of having unphysical (Landau) singularities it remains smooth and
finite there, due to infared (IR) fixed point. This behavior is suggested by:
Gribov-Zwanziger approach, Dyson-Schwinger equations (DSE) and other functional
methods, lattice calculations, light-front holographic mapping AdS/CFT modified
by a dilaton background, and by most of the analytic (holomorphic) QCD models.
All such couplings, A(Q^2), differ from the pQCD couplings a(Q^2) at |Q| > 1
GeV by nonperturbative (NP) terms, typically by some power-suppressed terms
~1/(Q^2)^N. Evaluations of low-energy physical QCD quantities in terms of such
A(Q^2) couplings (with IR fixed point) at a level beyond one-loop are usually
performed with (truncated) power series in A(Q^2). We argue that such an
evaluation is not correct, because the NP terms in general get out of control
as the number of terms in the power series increases. The series consequently
become increasingly unstable under the variation of the renormalization scale,
and have a fast asymptotic divergent behavior compounded by the renormalon
problem. We argue that an alternative series in terms of logarithmic
derivatives of A(Q^2) should be used. Further, a Pad\'e-related resummation
based on this series gives results which are renormalization scale independent
and show very good convergence. Timelike low-energy observables can be
evaluated analogously, using the integral transformation which relates the
timelike observable with the corresponding spacelike observable.


title:
Ultra-weak formulation of a hypersingular integral equation on polygons
  and DPG method with optimal test functions

abstract:
  We present an ultra-weak formulation of a hypersingular integral equation on
closed polygons and prove its well-posedness and equivalence with the standard
variational formulation. Based on this ultra-weak formulation we present a
discontinuous Petrov-Galerkin method with optimal test functions and prove its
quasi-optimal convergence in $L^2$. Theoretical results are confirmed by
numerical experiments on an open curve with uniform and adaptively refined
meshes.


title:
Fractional Topological Phases in Generalized Hofstadter Bands with
  Arbitrary Chern Numbers

abstract:
  We construct generalized Hofstadter models that possess "color-entangled"
flat bands and study interacting many-body states in such bands. For a system
with periodic boundary conditions and appropriate interactions, there exist
gapped states at certain filling factors for which the ground-state degeneracy
depends on the number of unit cells along one particular direction. This
puzzling observation can be understood intuitively by mapping our model to a
single-layer or a multilayer system for a given lattice configuration. We
discuss the relation between these results and the previously proposed
"topological nematic states," in which lattice dislocations have non-Abelian
braiding statistics. Our study also provides a systematic way of stabilizing
various fractional topological states in $C>1$ flat bands and provides some
hints on how to realize such states in experiments.


title:
Fundamental Physics and General Relativity with the LARES and LAGEOS
  satellites

abstract:
  Current observations of the universe have strengthened the interest to
further test General Relativity and other theories of fundamental physics.
After an introduction to the phenomenon of frame-dragging predicted by
Einstein's theory of General Relativity, with fundamental astrophysical
applications to rotating black holes, we describe the past measurements of
frame-dragging obtained by the LAGEOS satellites and by the dedicated Gravity
Probe B space mission. We also discuss a test of String Theories of
Chern-Simons type that has been carried out using the results of the LAGEOS
satellites. We then describe the LARES space experiment. LARES was successfully
launched in February 2012 to improve the accuracy of the tests of
frame-dragging, it can also improve the test of String Theories. We present the
results of the first few months of observations of LARES, its orbital analyses
show that it has the best agreement of any other satellite with the
test-particle motion predicted by General Relativity. We finally briefly report
the accurate studies and the extensive simulations of the LARES space
experiment, confirming an accuracy of a few percent in the forthcoming
measurement of frame-dragging.


title:
Towards a Unified Belief Structure in Games with indeterminate
  probabilities

abstract:
  This paper provides an analysis of different formal representations of
beliefs in epistemic game theory. The aim is to attempt a synthesis of
different structures of beliefs in the presence of indeterminate probabilities.
Special attention is also paid to the decision-theoretic principle known as the
thesis of no subjective probability for self-action. Conditions in cope with
this principle are given which underlie the interrelationships between
different models of beliefs, and it is shown that under these conditions
different doxastic structures can be coherently unified.


title: The Hahn superalgebra and supersymmetric Dunkl oscillator models

abstract:
  A supersymmetric extension of the Hahn algebra is introduced. This quadratic
superalgebra, which we call the Hahn superalgebra, is constructed using the
realization provided by the Dunkl oscillator model in the plane, whose
Hamiltonian involves reflection operators. In this realization, the reflections
act as grading operators and the odd generators are part of the Schwinger-Dunkl
algebra, which is a two-parameter extension of the bosonic su(2) construction.
The even part of the algebra is built from bilinears in the odd generators and
satisfy the Hahn algebra supplemented with involutions. A family of
supersymmetric Dunkl oscillator models in n dimensions is also considered. The
Hamiltonians of these supersymmetric models differ from ordinary Dunkl
oscillators by pure reflection terms. In two dimensions, the supersymmetric
Dunkl oscillator is seen to have the even part of the Hahn superalgebra as
invariance algebra.


title: Multivariate Central Limit Theorem in Quantum Dynamics

abstract:
  We consider the time evolution of $N$ bosons in the mean field regime for
factorized initial data. In the limit of large $N$, the many body evolution can
be approximated by the non-linear Hartree equation. In this paper we are
interested in the fluctuations around the Hartree dynamics. We choose $k$
self-adjoint one-particle operators $O_1, \dots, O_k$ on $L^2 (\R^3)$, and we
average their action over the $N$-particles. We show that, for every fixed $t
\in \R$, expectations of products of functions of the averaged observables
approach, as $N \to \infty$, expectations with respect to a complex Gaussian
measure, whose covariance matrix can be expressed in terms of a Bogoliubov
transformation describing the dynamics of quantum fluctuations around the mean
field Hartree evolution. If the operators $O_1, \dots, O_k$ commute, the
Gaussian measure is real and positive, and we recover a "classical"
multivariate central limit theorem. All our results give explicit bounds on the
rate of the convergence (we obtain therefore Berry-Ess{\'e}en type central
limit theorems).


title:
Microwave and EUV Observations of an Erupting Filament and Associated
  Flare and CME

abstract:
  A filament eruption was observed with the Siberian Solar Radio Telescope
(SSRT) on June 23 2012, starting around 06:40 UT, beyond the West limb. The
filament could be followed in SSRT images to heights above 1 Rs, and coincided
with the core of the CME, seen in LASCO C2 images. We discuss briefly the
dynamics of the eruption: the top of the filament showed a smooth acceleration
up to an apparent velocity of 1100 km/s. Images behind the limb from STEREO-A
show a two ribbon flare and the interaction of the main filament, located along
the primary neutral line, with an arch-like structure, oriented in the
perpendicular direction. The interaction was accompanied by strong emission and
twisting motions. The microwave images show a low temperature component, a high
temperature component associated with the interaction of the two filaments and
another high temperature component apparently associated with the top of flare
loops. We computed the differential emission measure from the high temperature
AIA bands and from this the expected microwave brightness temperature; for the
emission associated with the top of flare loops the computed brightness was 35%
lower than the observed.


title:
Experimental study of a low-order wavefront sensor for the high-contrast
  coronagraphic imager EXCEDE

abstract:
  The mission EXCEDE (EXoplanetary Circumstellar Environments and Disk
Explorer), selected by NASA for technology development, is designed to study
the formation, evolution and architectures of exoplanetary systems and
characterize circumstellar environments into stellar habitable zones. It is
composed of a 0.7 m telescope equipped with a Phase-Induced Amplitude
Apodization Coronagraph (PIAA-C) and a 2000-element MEMS deformable mirror,
capable of raw contrasts of 1e-6 at 1.2 lambda/D and 1e-7 above 2 lambda/D. One
of the key challenges to achieve those contrasts is to remove low-order
aberrations, using a Low-Order WaveFront Sensor (LOWFS). An experiment
simulating the starlight suppression system is currently developed at NASA Ames
Research Center, and includes a LOWFS controlling tip/tilt modes in real time
at 500 Hz. The LOWFS allowed us to reduce the tip/tilt disturbances to 1e-3
lambda/D rms, enhancing the previous contrast by a decade, to 8e-7 between 1.2
and 2 lambda/D. A Linear Quadratic Gaussian (LQG) controller is currently
implemented to improve even more that result by reducing residual vibrations.
This testbed shows that a good knowledge of the low-order disturbances is a key
asset for high contrast imaging, whether for real-time control or for post
processing.


title:
Time-dependent renormalized natural orbital theory applied to the
  two-electron spin-singlet case: ground state, linear response, and
  autoionization

abstract:
  Favorably scaling numerical time-dependent many-electron techniques such as
time-dependent density functional theory (TDDFT) with adiabatic
exchange-correlation potentials typically fail in capturing highly correlated
electron dynamics. We propose a method based on natural orbitals, i.e., the
eigenfunctions of the one-body reduced density matrix, that is almost as
inexpensive numerically as adiabatic TDDFT, but which is capable of describing
correlated phenomena such as doubly excited states, autoionization, Fano
profiles in the photoelectron spectra, and strong-field ionization in general.
Equations of motion (EOM) for natural orbitals and their occupation numbers
have been derived earlier. We show that by using renormalized natural orbitals
(RNO) both can be combined into one equation governed by a hermitian effective
Hamiltonian. We specialize on the two-electron spin-singlet system, known as
being a "worst case" testing ground for TDDFT, and employ the widely used,
numerically exactly solvable, one-dimensional helium model atom (in a laser
field) to benchmark our approach. The solution of the full, nonlinear EOM for
the RNO is plagued by instabilities, and resorting to linear response is not an
option for the ultimate goal to study nonperturbative dynamics in intense laser
fields. We therefore make two rather bold approximations: we employ the
initial-state-"frozen" effective RNO Hamiltonian for the time-propagation and
truncate the number of RNO to only two per spin. Surprisingly, it turns out
that even with these strong approximations we obtain a highly accurate ground
state, reproduce doubly-excited states, and autoionization.

categories: physics.atom-ph physics.chem-ph physics.comp-ph quant-ph


title:
MgB2 nonlinear properties investigated under localized high rf magnetic
  field excitation-report 2

abstract:
  The high transition temperature and low surface resistance of MgB2 attracts
interest in its potential application in superconducting radio frequency
accelerating cavities. However, compared to traditional Nb cavities, the
viability of MgB2 at high rf fields is still open to question. Our approach is
to study the nonlinear electrodynamics of the material under localized rf
magnetic fields. Because of the presence of the small superconducting gap in
the $\pi$ band, the nonlinear response of MgB2 at low temperature is
potentially complicated compared to a single-gap s-wave superconductor such as
Nb. Understanding the mechanisms of nonlinearity coming from the two-band
structure of MgB2, as well as extrinsic sources of nonlinearity, is an urgent
requirement. A localized and strong rf magnetic field, created by a magnetic
write head, is integrated into our nonlinear-Meissner-effect scanning microwave
microscope [Tamin Tai, X. X. Xi, C. G. Zhuang, D. I. Mircea, and S. M. Anlage,
IEEE Trans. Appl. Supercond. 21, 2615 (2011)]. MgB2 films with thickness 50 nm,
fabricated by a hybrid physical-chemical vapor deposition technique on
dielectric substrates, are measured at a fixed location and show a strongly
temperature-dependent third harmonic response. We propose that several possible
mechanisms are responsible for this nonlinear response.


title: Inequalities for the Gaussian measure of convex sets

abstract:
  This note presents families of inequalities for the Gaussian measure of
convex sets which extend the recently proven Gaussian correlation inequality in
various directions.


title: Photoexcitation of graphene with twisted light

abstract:
  We study theoretically the interaction of twisted light with graphene. The
light-matter interaction matrix elements between the tight-binding states of
electrons in graphene are determined near the Dirac points. We examine the
dynamics of the photoexcitation process by posing the equations of motion of
the density matrix and working up to second order in the field. The time
evolution of the angular momentum of the photoexcited electrons and their
associated photocurrents are examined in order to elucidate the mechanisms of
angular momentum transfer. We find that the transfer of spin and orbital
angular momentum from light to the electrons is more akin here to the case of
intraband than of interband transitions in semiconductors, due to the fact that
the two relevant energy bands of graphene originate from the same atomic
orbitals.


title: Anomaly-free U(1) gauge symmetries in neutrino seesaw flavor models

abstract:
  Adding right-handed neutrino singlets and/or fermion triplets to the particle
content of the Standard Model allows for the implementation of the seesaw
mechanism to give mass to neutrinos and, simultaneously, for the construction
of anomaly-free gauge group extensions of the theory. We consider Abelian
extensions based on an extra U(1)_X gauge symmetry, where X is an arbitrary
linear combination of the baryon number B and the individual lepton numbers
L_{e,mu,tau}. By requiring cancellation of gauge anomalies, we perform a
detailed analysis in order to identify the charge assignments under the new
gauge symmetry that lead to neutrino phenomenology compatible with current
experiments. In particular, we study how the new symmetry can constrain the
flavor structure of the Majorana neutrino mass matrix, leading to two-zero
textures with a minimal extra fermion and scalar content. The possibility of
distinguishing different gauge symmetries and seesaw realizations at colliders
is also briefly discussed.


title: An operational approach to indirectly measuring tunneling time

abstract:
  The tunneling time through an arbitrary bounded one-dimensional barrier is
investigated using the dwell time operator. We relate the tunneling time to the
conditioned average of the dwell time operator because of the natural
post-selection in the case of successful tunneling. We discuss an indirect
measurement by timing the particle, and show we are able to reconstruct the
conditioned average value of the dwell time operator by applying the contextual
values formalism for generalized measurements based on the physics of Larmor
precession. The experimentally measurable tunneling time in the weak
interaction limit is given by the weak value of the dwell time operator plus a
measurement-context dependent disturbance term. We show how the expectation
value and higher moments of the dwell time operator can be extracted from
measurement data of the particle's spin.


title: Could Jean-Dominique Cassini see the famous division in Saturn's rings?

abstract:
  Nowadays, astronomers want to observe gaps in exozodiacal disks to confirm
the presence of exoplanets, or even make actual images of these companions.
Four hundred and fifty years ago, Jean-Dominique Cassini did a similar study on
a closer object: Saturn. After joining the newly created Observatoire de Paris
in 1671, he discovered 4 of Saturn's satellites (Iapetus, Rhea, Tethys and
Dione), and also the gap in its rings. He made these discoveries observing
through the best optics at the time, made in Italy by famous opticians like
Giuseppe Campani or Eustachio Divini. But was he really able to observe this
black line in Saturn's rings? That is what a team of optical scientists from
Observatoire de Paris - LESIA with the help of Onera and Institut d'Optique
tried to find out, analyzing the lenses used by Cassini, and still preserved in
the collection of the observatory. The main difficulty was that even if the
lenses have diameters between 84 and 239 mm, the focal lengths are between 6
and 50 m, more than the focal lengths of the primary mirrors of future ELTs.
The analysis shows that the lenses have an exceptionally good quality, with a
wavefront error of approximately 50 nm rms and 200 nm peak-to-valley, leading
to Strehl ratios higher than 0.8. Taking into account the chromaticity of the
glass, the wavefront quality and atmospheric turbulence, reconstructions of his
observations tend to show that he was actually able to see the division named
after him.


title:
Strong traces for averaged solutions of heterogeneous ultra-parabolic
  transport equations

abstract:
  We prove that if traceability conditions are fulfilled then a weak solution
$h\in L^\infty(\R^+\times\R^d\times \R)$ to {the ultra-parabolic transport
equation} \begin{equation*} \pa_t h + \Div_x
\left(F(t,x,\lambda)h\right)=\sum\limits_{i,j=1}^k\pa^2_{x_i
x_j}\left(b_{ij}(t,x,\lambda) h\right)+\pa_\lambda \gamma(t,x,\lambda),
\end{equation*} is such that for every $\rho\in C^1_c(\R)$, the velocity
averaged quantity $\int_{\R}h(t,x,\lambda)$ $\rho(\lambda)d\lambda$ admits the
strong $L^1_{\rm loc}(\R^d)$-limit as $t\to 0$, i.e. there exist
$h_0(x,\lambda)\in L^1_{\rm loc}(\R^d\times \R)$ and the set $E\subset\R^+$ of
full measure such that for every $\rho\in C^1_c(\R)$, $$ L^1_{\rm
loc}(\R^d)-\lim\limits_{t\to 0, \; t\in E} \int_{\R}
h(t,x,\lambda)\rho(\lambda)d\lambda= \int_{\R} h_0(x,\lambda)
\rho(\lambda)d\lambda. $$ As a corollary, under the traceability conditions, we
prove existence of strong traces for entropy solutions to ultraparabolic
equations in heterogeneous media.


title:
Compact atomic gravimeter based on a pulsed and accelerated optical
  lattice

abstract:
  We present a new scheme of compact atomic gravimeter based on atom
interferometry. Atoms are maintained against gravity using a sequence of
coherent accelerations performed by the Bloch oscillations technique. We
demonstrate a sensitivity of 4.8$\times 10^{-8}$ with an integration time of 4
min. Combining this method with an atomic elevator allows to measure the local
gravity at different positions in the vacuum chamber. This method can be of
relevance to improve the measurement of the Newtonian gravitational constant
$G$.


title:
Flashmon V2: Monitoring Raw NAND Flash Memory I/O Requests on Embedded
  Linux

abstract:
  This paper presents Flashmon version 2, a tool for monitoring embedded Linux
NAND flash memory I/O requests. It is designed for embedded boards based
devices containing raw flash chips. Flashmon is a kernel module and stands for
"flash monitor". It traces flash I/O by placing kernel probes at the NAND
driver level. It allows tracing at runtime the 3 main flash operations: page
reads / writes and block erasures. Flashmon is (1) generic as it was
successfully tested on the three most widely used flash file systems that are
JFFS2, UBIFS and YAFFS, and several NAND chip models. Moreover, it is (2) non
intrusive, (3) has a controllable memory footprint, and (4) exhibits a low
overhead (<6%) on the traced system. Finally, it is (5) simple to integrate and
used as a standalone module or as a built-in function / module in existing
kernel sources. Monitoring flash memory operations allows a better
understanding of existing flash management systems by studying and analyzing
their behavior. Moreover it is useful in development phase for prototyping and
validating new solutions.


title:
Analysis of low energy response and possible emergent SU(4) Kondo state
  in a double quantum dot

abstract:
  We examine the low energy behavior of a double quantum dot in a regime where
spin and pseudospin excitations are degenerate. The individual quantum dots are
described by Anderson impurity models with an on-site interaction $U$ which are
capacitively coupled by an interdot interaction $U_{12}<U$. The low energy
response functions are expressed in terms of renormalized parameters, which can
be deduced from an analysis of the fixed point in a numerical renormalization
group calculation. At the point where the spin and pseudospin degrees of
freedom become degenerate, the free quasiparticle excitations have a phase
shift of $\pi/4$ and a 4-fold degeneracy. We find, however, when the
quasiparticle interactions are included, that the low energy effective model
has SU(4) symmetry only in the special case $U_{12}=U$ unless both $U$ and
$U_{12}$ are greater than $D$, the half-bandwidth of the conduction electron
bath. We show that the gate voltage dependence of the temperature dependent
differential conductance observed in recent experiments can be described by a
quasiparticle density of states with temperature dependent renormalized
parameters.


title: Etingof conjecture for quantized quiver varieties

abstract:
  We compute the number of finite dimensional irreducible modules for the
algebras quantizing Nakajima quiver varieties. We get a lower bound for all
quivers and vectors of framing and provide an exact count in the case when the
quiver is of finite type or is of affine type and the framing is the coordinate
vector at the extending vertex. The latter case precisely covers Etingof's
conjecture on the number of finite dimensional irreducible representations for
Symplectic reflection algebras associated to wreath-product groups. We use
several different techniques, the two principal ones are categorical Kac-Moody
actions and wall-crossing functors. We finish the paper outlining some future
directions of research.


title: On the Theory of Wave Packets

abstract:
  In this paper we discuss some aspects of the theory of wave packets. We
consider a popular non-covariant Gaussian model used in various applications
and show that it predicts too slow a longitudinal dispersion rate for
relativistic particles. We revise this approach by considering a covariant
model of Gaussian wave packets, and examine our results by inspecting a wave
packet of arbitrary form. A general formula for the time dependence of the
dispersion of a wave packet of arbitrary form is found. Finally, we give a
transparent interpretation of the disappearance of the wave function over time
due to the dispersion --- a feature often considered undesirable, but which is
unavoidable for wave packets. We find, starting from simple examples,
proceeding with their generalizations and finally by considering the continuity
equation, that the integral over time of both the flux and probability
densities are asymptotically proportional to the factor 1/L^2 in the rest frame
of the wave packet, just as in the case of an ensemble of classical particles.


title:
Investigating the effects of finite resolution on observed transverse
  Rotation Measure distributions

abstract:
  Both the emission properties and evolution of Active Galactic Nuclei (AGN)
radio jets are dependent on the magnetic (B) fields that thread them. Faraday
Rotation measurements are a very important way of investigating these B fields,
and can provide information on the orientation and structure of the B field in
the immediate vicinity of the jet; for example, a toroidal or helical B field
component should give rise to a systematic gradient in the observed Faraday
rotation across the jet, as well as characteristic intensity and polarization
profiles. However, real observed radio images have finite resolution, usually
expressed via convolution with a Gaussian beam whose size corresponds to the
central lobe of the point source response function. This will tend to blur the
transverse structure of the jet, raising the question of how well resolved a
jet must be in the transverse direction in order to reliably detect transverse
structure. We present the results of simulated Faraday rotation images designed
to directly investigate the effect of finite resolution on observed transverse
Faraday rotation measure structures.


title: Information transfer from black holes via white holes

abstract:
  It is shown that a black hole can be in two states: one with positive and
other with negative surface gravity $k$. The state with $k<0$ corresponds to a
white hole. In this state there is no information loss. In the quantization of
black hole area the surface of a black hole is divided into a system of
independent patches, each of which can be in two states: one with $k>0$ and
other with $k<0$. Then the entropy goes like the area and information can be
recovered from the black hole.


title: Implementation of PDE models of cardiac dynamics on GPUs using OpenCL

abstract:
  Graphical processing units (GPUs) promise to revolutionize scientific
computing in the near future. Already, they allow almost real-time integration
of simplified numerical models of cardiac tissue dynamics. However, the
integration methods that have been developed so far are typically of low order
and use single precision arithmetics. In this work, we describe numerical
implementation of double precision integrators required by, e.g., matrix-free
Newton-Krylov solvers and compare several higher order, fully explicit
numerical methods using finite-difference discretization of a range of models
of two-dimensional cardiac tissue.


title: Dark Matter Thermalization in Neutron Stars

abstract:
  We study how many-body effects alter the dark matter (DM) thermalization time
inside neutron stars. We find that Pauli blocking, kinematic constraints, and
superfluidity and superconductivity in the neutron star significantly affect
the DM thermalization time, in general lengthening it. This could change the
final DM mass and DM-nucleon cross section constraints by considering black
hole formation in neutron stars due to DM accretion. We consider the class of
models in which DM is an asymmetric, complex scalar particle with a mass
between 1 keV and 5 GeV which couples to regular matter via some heavy vector
boson. Interestingly, we find that the discovery of asymmetric, bosonic DM
could motivate the existence of exotic neutron star cores. We apply our results
to the case of mixed sneutrino DM.