title:
Enhanced Halpha activity at periastron in the young and massive
  spectroscopic binary HD200775

abstract:
  Young close binaries clear central cavities in their surrounding circumbinary
disk from which the stars can still accrete material. This process takes place
within the very first astronomical units, and is still not well constrained as
the observational evidence has been gathered, until now, only by means of
spectroscopy. The young object HD200775 (MWC361) is a massive spectroscopic
binary (separation of ~15.9mas, ~5.0~AU), with uncertain classification
(early/late Be), that shows a strong and variable Halpha emission. We aim to
study the mechanisms that produce the Halpha line at the AU-scale. Combining
the radial velocity measurements and astrometric data available in the
literature, we determined new orbital parameters. With the VEGA instrument on
the CHARA array, we spatially and spectrally resolved the Halpha emission of
HD200775, at low and medium spectral resolutions (R~1600 and 5000) over a full
orbital period (~3.6 years). We observe that the Halpha equivalent width varies
with the orbital phase, and increases close to periastron, as expected from
theoretical models that predict an increase of the mass transfer from the
circumbinary disk to the primary disk. In addition, using spectral visibilities
and differential phases, we find marginal variations of the typical extent of
the Halpha emission (at 1 to 2-sigma level) and location (at 1 to 5-sigma
level). The spatial extent of the Halpha emission, as probed by a Gaussian
FWHM, is minimum at the ascending node (0.67+/-0.20 mas, i.e., 0.22+/-0.06 AU),
and more than doubles at periastron. In addition, the Gaussian photocenter is
slightly displaced in the direction opposite to the secondary, ruling out the
scenario in which all or most of the Halpha emission is due to accretion onto
the secondary. These findings, together with the wide Halpha line profile, may
be due to a non-spherical wind enhanced at periastron.


title:
Optical properties of monoclinic HfO2 studied by first-principles local
  density approximation +U approach

abstract:
  The band structures and optical properties of monoclinic HfO2 are
investigated by the local density approximation (LDA)+U approach. With the
on-site Coulomb interaction being introduced to 5d orbitals of Hf atom and 2p
orbitals of O atom, the experimental band gap is reproduced. The imaginary part
of the complex dielectric function shows a small shoulder at the edge of the
band gap, coinciding with the experiments. This intrinsic property of
crystallized monoclinic HfO2, which is absent in both the tetragonal phase and
cubic phase, can be understood as a consequence of the reconstruction of the
electronic states near the band edge following the adjustment of the crystal
structure. The existence of a similar shoulder-like-structure in the monoclinic
phase of ZrO2 is predicted.


title: Faber-Krahn inequalities in sharp quantitative form

abstract:
  The classical Faber-Krahn inequality asserts that balls (uniquely) minimize
the first eigenvalue of the Dirichlet-Laplacian among sets with given volume.
In this paper we prove a sharp quantitative enhancement of this result, thus
confirming a conjecture by Nadirashvili and Bhattacharya-Weitsman. More
generally, the result applies to every optimal Poincar\'e-Sobolev constant for
the embeddings $W^{1,2}_0(\Omega)\hookrightarrow L^q(\Omega)$.


title: Learning from networked examples in a k-partite graph

abstract:
  Many machine learning algorithms are based on the assumption that training
examples are drawn independently. However, this assumption does not hold
anymore when learning from a networked sample where two or more training
examples may share common features. We propose an efficient weighting method
for learning from networked examples and show the sample error bound which is
better than previous work.


title: Constraining Torsion in Maximally symmetric (sub)spaces

abstract:
  We look into the general aspects of space-time symmetries in presence of
torsion, and how the latter is affected by such symmetries. Focusing in
particular to space-times which either exhibit maximal symmetry on their own,
or could be decomposed to maximally symmetric subspaces, we work out the
constraints on torsion in two different theoretical schemes. We show that at
least for a completely antisymmetric torsion tensor (for e.g. the one motivated
from string theory), an equivalence is set between these two schemes, as the
non-vanishing independent torsion tensor components turn out to be the same.


title:
Optical control of a magnetic Feshbach resonance in ultracold Fermi
  gases

abstract:
  We use laser light near-resonant with a molecular bound-to-bound transition
to control a magnetic Feshbach resonance in ultracold Fermi gases of $^{40}$K
atoms. The spectrum of excited molecular states is measured by applying a laser
field that couples the ground Feshbach molecular state to electronically
excited molecular states. Nine strong bound-to-bound resonances are observed
below the $^{2}P_{1/2}+^{2}S_{1/2}$ threshold. We use radio-frequency
spectroscopy to characterize the laser-dressed bound state near a specific
bound-to-bound resonance and show clearly the shift of the magnetic Feshbach
resonance using light with negligible atomic loss. The demonstrated technology
could be used to modify interatomic interactions with high spatial and temporal
resolutions in the crossover regime from a Bose-Einstein condensate (BEC) to a
Bardeen-Cooper-Schrieffer (BCS) superfluid.


title:
Quantized conductance and its correlation to the supercurrent in a
  nanowire connected to superconductors

abstract:
  We report conductance and supercurrent of InAs nanowires coupled to
Al-superconducting electrodes with short channel lengths and good Ohmic
contacts. The nanowires are suspended 15\,nm above a local gate electrode. The
charge density in the nanowires can be controlled by a small change in the gate
voltage. For large negative gate voltages, the number of conducting channels is
reduced gradually and we observe a stepwise decrease of both conductance and
critical current before the conductance vanishes completely.


title:
Deceleration and trapping of ammonia molecules in a traveling wave
  decelerator

abstract:
  We have recently demonstrated static trapping of ammonia isotopologues in a
decelerator that consists of a series of ring-shaped electrodes to which
oscillating high voltages are applied [Quintero-P\'{e}rez et al., Phys. Rev.
Lett. 110, 133003 (2013)]. In this paper we provide further details on this
traveling wave decelerator and present new experimental data that illustrate
the control over molecules that it offers. We analyze the performance of our
setup under different deceleration conditions and demonstrate phase-space
manipulation of the trapped molecular sample.


title: Quantum rotor model for a Bose-Einstein condensate of dipolar molecules

abstract:
  We show that a Bose-Einstein condensate of heteronuclear molecules in the
regime of small and static electric fields is described by a quantum rotor
model for the macroscopic electric dipole moment of the molecular gas cloud. We
solve this model exactly and find the symmetric, i.e., rotationally invariant,
and dipolar phases expected from the single-molecule problem, but also an axial
and planar nematic phase due to many-body effects. Investigation of the
wavefunction of the macroscopic dipole moment also reveals squeezing of the
probability distribution for the angular momentum of the molecules.


title:
A Variation of Dirac Equation, Based on SO(2,1) Group, with Applications
  to Low Dimensional Systems

abstract:
  A variation of Dirac equation based on SO(2,1) group is suggested for
treating low dimensional systems in the three dimensional x,y,t space.
Non-unitary representations are developed in an analogous way to those used in
the ordinary Dirac equations and quantum field theory is developed for the
present SO(2,1) relativistic equation. The theory is applied for low
dimensional systems including especially holes-electrons pairs, or other
two-particle states, in the low dimensional space.


title: The RAM equivalent of P vs. RP

abstract:
  One of the fundamental open questions in computational complexity is whether
the class of problems solvable by use of stochasticity under the Random
Polynomial time (RP) model is larger than the class of those solvable in
deterministic polynomial time (P). However, this question is only open for
Turing Machines, not for Random Access Machines (RAMs).
  Simon (1981) was able to show that for a sufficiently equipped Random Access
Machine, the ability to switch states nondeterministically does not entail any
computational advantage. However, in the same paper, Simon describes a
different (and arguably more natural) scenario for stochasticity under the RAM
model. According to Simon's proposal, instead of receiving a new random bit at
each execution step, the RAM program is able to execute the pseudofunction
$\textit{RAND}(y)$, which returns a uniformly distributed random integer in the
range $[0,y)$. Whether the ability to allot a random integer in this fashion is
more powerful than the ability to allot a random bit remained an open question
for the last 30 years.
  In this paper, we close Simon's open problem, by fully characterising the
class of languages recognisable in polynomial time by each of the RAMs
regarding which the question was posed. We show that for some of these,
stochasticity entails no advantage, but, more interestingly, we show that for
others it does.


title: A note on the electrostatic energy of two point charges

abstract:
  The electrostatic field energy due to two fixed pointlike charges shows some
peculiar features concerning the distribution in space of the field energy
density of the system. Here we discuss the evaluation of the field energy and
the mathematical details that lead to those peculiar and non-intuitive physical
features.


title:
Microwave sidebands for laser cooling by direct modulation of a tapered
  amplifier

abstract:
  Laser cooling of atoms usually necessitates several laser frequencies.
Alkaline atoms, for example, are cooled by two lasers with a frequency
difference in the Gigahertz range. This gap cannot be closed with simple
shifting techniques. Here, we present a method of generating sidebands at 6.6
GHz by modulating the current of a tapered amplifier which is seeded by an
unmodulated master laser. The sidebands enable trapping of 1.1*10^9 Rubidium 87
atoms in a chip-based magneto-optical trap. Compared to the direct modulation
of the master laser, this method allows for an easy implementation, a fast
adjustment over a wide frequency range and the simultaneous extraction of
unmodulated light for manipulation and detection. The low power consumption,
small size and applicability for multiple frequencies benefits a wide range of
applications, reaching from atom-based mobile sensors to the laser cooling of
molecules.

categories: physics.atom-ph cond-mat.quant-gas physics.optics quant-ph


title: On the Sidon Constant for Dirichlet Polynomials

abstract:
  We estimate the error term in the asymptotic formula of the Sidon constant
for (ordinary) Dirichlet polynomials by providing explicit lower and upper
bounds. The lower bound is already implicitly known, but we supply the
necessary computations to make it explicit. The upper bound is improved by a
factor of $\log\log\log{x}/\sqrt{\log\log{x}}$.


title: Iterative Grassmannian Optimization for Robust Image Alignment

abstract:
  Robust high-dimensional data processing has witnessed an exciting development
in recent years, as theoretical results have shown that it is possible using
convex programming to optimize data fit to a low-rank component plus a sparse
outlier component. This problem is also known as Robust PCA, and it has found
application in many areas of computer vision. In image and video processing and
face recognition, the opportunity to process massive image databases is
emerging as people upload photo and video data online in unprecedented volumes.
However, data quality and consistency is not controlled in any way, and the
massiveness of the data poses a serious computational challenge. In this paper
we present t-GRASTA, or "Transformed GRASTA (Grassmannian Robust Adaptive
Subspace Tracking Algorithm)". t-GRASTA iteratively performs incremental
gradient descent constrained to the Grassmann manifold of subspaces in order to
simultaneously estimate a decomposition of a collection of images into a
low-rank subspace, a sparse part of occlusions and foreground objects, and a
transformation such as rotation or translation of the image. We show that
t-GRASTA is 4 $\times$ faster than state-of-the-art algorithms, has half the
memory requirement, and can achieve alignment for face images as well as
jittered camera surveillance images.


title:
Self-bound many-body states of quasi-one-dimensional dipolar Fermi
  gases: Exploiting Bose-Fermi mappings for generalized contact interactions

abstract:
  Using a combination of results from exact mappings and from mean-field theory
we explore the phase diagram of quasi-one-dimensional systems of identical
fermions with attractive dipolar interactions. We demonstrate that at low
density these systems provide a realization of a single-component
one-dimensional Fermi gas with a generalized contact interaction. Using an
exact duality between one-dimensional Fermi and Bose gases, we show that when
the dipole moment is strong enough, bound many-body states exist, and we
calculate the critical coupling strength for the emergence of these states. At
higher densities, the Hartree-Fock approximation is accurate, and by combining
the two approaches we determine the structure of the phase diagram. The
many-body bound states should be accessible in future experiments with
ultracold polar molecules.


title:
Managing Unbounded-Length Keys in Comparison-Driven Data Structures with
  Applications to On-Line Indexing

abstract:
  This paper presents a general technique for optimally transforming any
dynamic data structure that operates on atomic and indivisible keys by
constant-time comparisons, into a data structure that handles unbounded-length
keys whose comparison cost is not a constant. Examples of these keys are
strings, multi-dimensional points, multiple-precision numbers, multi-key data
(e.g.~records), XML paths, URL addresses, etc. The technique is more general
than what has been done in previous work as no particular exploitation of the
underlying structure of is required. The only requirement is that the insertion
of a key must identify its predecessor or its successor.
  Using the proposed technique, online suffix tree can be constructed in worst
case time $O(\log n)$ per input symbol (as opposed to amortized $O(\log n)$
time per symbol, achieved by previously known algorithms). To our knowledge,
our algorithm is the first that achieves $O(\log n)$ worst case time per input
symbol. Searching for a pattern of length $m$ in the resulting suffix tree
takes $O(\min(m\log |\Sigma|, m + \log n) + tocc)$ time, where $tocc$ is the
number of occurrences of the pattern. The paper also describes more
applications and show how to obtain alternative methods for dealing with suffix
sorting, dynamic lowest common ancestors and order maintenance.


title:
Constructive Setting of the Density Ratio Estimation Problem and its
  Rigorous Solution

abstract:
  We introduce a general constructive setting of the density ratio estimation
problem as a solution of a (multidimensional) integral equation. In this
equation, not only its right hand side is known approximately, but also the
integral operator is defined approximately. We show that this ill-posed problem
has a rigorous solution and obtain the solution in a closed form. The key
element of this solution is the novel V-matrix, which captures the geometry of
the observed samples. We compare our method with three well-known previously
proposed ones. Our experimental results demonstrate the good potential of the
new approach.


title:
Non-stationary Spatial Modelling with Applications to Spatial Prediction
  of Precipitation

abstract:
  A non-stationary spatial Gaussian random field (GRF) is described as the
solution of an inhomogeneous stochastic partial differential equation (SPDE),
where the covariance structure of the GRF is controlled by the coefficients in
the SPDE. This allows for a flexible way to vary the covariance structure,
where intuition about the resulting structure can be gained from the local
behaviour of the differential equation. Additionally, computations can be done
with computationally convenient Gaussian Markov random fields which approximate
the true GRFs. The model is applied to a dataset of annual precipitation in the
conterminous US. The non-stationary model performs better than a stationary
model measured with both CRPS and the logarithmic scoring rule.


title: On a generalized entropic uncertainty relation in the case of the qubit

abstract:
  We revisit generalized entropic formulations of the uncertainty principle for
an arbitrary pair of quantum observables in two-dimensional Hilbert space.
R\'enyi entropy is used as uncertainty measure associated with the distribution
probabilities corresponding to the outcomes of the observables. We derive a
general expression for the tight lower bound of the sum of R\'enyi entropies
for any couple of (positive) entropic indices (\alpha,\beta). Thus, we have
overcome the H\"older conjugacy constraint imposed on the entropic indices by
Riesz-Thorin theorem. In addition, we present an analytical expression for the
tight bound inside the square [0 , 1/2] x [0 , 1/2] in the \alpha-\beta plane,
and a semi-analytical expression on the line \beta = \alpha. It is seen that
previous results are included as particular cases. Moreover, we present an
analytical but suboptimal bound for any couple of indices. In all cases, we
provide the minimizing states.


title: Shortcuts to adiabaticity by counter-diabatic driving

abstract:
  The evolution of a system induced by counter-diabatic driving mimics the
adiabatic dynamics without the requirement of slow driving. Engineering it
involves diagonalizing the instantaneous Hamiltonian of the system and results
in the need of auxiliary non-local interactions for matter-waves. Here
experimentally realizable driving protocols are found for a large class of
single-particle, many-body, and non-linear systems without demanding the
spectral properties as an input. The method is applied to the fast
decompression of Bose-Einstein condensates in different trapping potentials.


title:
Lennard-Jones systems near solid walls: Computing interfacial free
  energies from molecular simulation methods

abstract:
  Different computational techniques in combination with molecular dynamics
computer simulation are used to to determine the wall-liquid and the
wall-crystal interfacial free energies of a modified Lennard-Jones (LJ) system
in contact with a solid wall. Two different kinds of solid walls are
considered: a flat structureless wall and a structured wall consisting of an
ideal crystal with the particles rigidly attached to fcc lattice sites.
Interfacial free energies are determined by a thermodynamic integration scheme,
the anisotropy of the pressure tensor, the non-equilibrium work method based on
Bennett acceptance criteria, and a method using Cahn's adsorption equations
based on the interfacial thermodynamics of Gibbs. For the flat wall,
interfacial free energies as a function of different densities of the LJ liquid
and as a function of temperature along the coexistence curve are calculated. In
case of a structured wall, the interaction strength between the wall and the LJ
system and the lattice constant of the structured wall are varied. Using the
values of the wall-liquid and wall-crystal interfacial energies along with the
value for the crystal-liquid interfacial free energy determined previously for
the same system by the "cleaving potential method", we obtain the contact angle
as a function of various parameters; in particular the conditions are found
under which partial wetting occurs.


title: $L^p$ compression of some HNN extensions

abstract:
  Using recent developments on locally compact groups, we are able to obtain
quantitative results on embeddings into Lebesgue spaces for a large class of
HNN extensions.


title:
GWmodel: an R Package for Exploring Spatial Heterogeneity using
  Geographically Weighted Models

abstract:
  Spatial statistics is a growing discipline providing important analytical
techniques in a wide range of disciplines in the natural and social sciences.
In the R package GWmodel, we introduce techniques from a particular branch of
spatial statistics, termed geographically weighted (GW) models. GW models suit
situations when data are not described well by some global model, but where
there are spatial regions where a suitably localised calibration provides a
better description. The approach uses a moving window weighting technique,
where localised models are found at target locations. Outputs are mapped to
provide a useful exploratory tool into the nature of the data spatial
heterogeneity. GWmodel includes: GW summary statistics, GW principal components
analysis, GW regression, GW regression with a local ridge compensation, and GW
regression for prediction; some of which are provided in basic and robust
forms.


title: Experimental refutation of a class of \psi-epistemic models

abstract:
  The quantum state is a mathematical object used to determine the outcome
probabilities of measurements on physical systems. Its fundamental nature has
been the subject of discussions since the origin of the theory: is it ontic,
that is, does it correspond to a real property of the physical system? Or is it
epistemic, that is, does it merely represent our knowledge about the system?
Recent advances in the foundations of quantum theory show that epistemic models
that obey a simple continuity condition are in conflict with quantum theory
already at the level of a single system. Here we report an experimental test of
continuous epistemic models using high-dimensional attenuated coherent states
of light traveling in an optical fibre. Due to non-ideal state preparation (of
coherent states with imperfectly known phase) and non-ideal measurements
(arising from losses and inefficient detection), this experiment only tests
epistemic models that satisfy additional constraints which we discuss in
detail. Our experimental results are in agreement with the predictions of
quantum theory and provide constraints on a class of \psi-epistemic models.


title: Equivalence between an optomechanical system and a Kerr medium

abstract:
  We study the optical bistability of an optomechanical system in which the
position of a mechanical oscillator modulates the cavity frequency. The
steady-state mean-field equation of the optical mode is identical to the one
for a Kerr medium, and thus we expect it to have the same characteristic
behavior with a lower, a middle, and an upper branch. However, the presence of
position fluctuations of the mechanical resonator leads to a new feature: the
upper branch will become unstable at sufficiently strong driving in certain
parameter regimes. We identify the appropriate parameter regime for the upper
branch to be stable, and we confirm, by numerical investigation of the quantum
steady state, that the mechanical mode indeed acts as a Kerr nonlinearity for
the optical mode in the low-temperature limit. This equivalence of the
optomechanical system and the Kerr medium will be important for future
applications of cavity optomechanics in quantum nonlinear optics and quantum
information science.


title: Phase transition in a super superspin glass

abstract:
  We here confirm the occurrence of spin glass phase transition and extract
estimates of associated critical exponents of a highly monodisperse and densely
compacted system of bare maghemite nanoparticles. This system has earlier been
found to behave like an archetypal spin glass, with e.g. a sharp transition
from paramagnetic to non-equilibrium behavior, suggesting that this system
undergoes a spin-glass phase transition at a relatively high temperature, $T_g$
$\sim$ 140 K.


title:
On the Cauchy problem for a new integrable two-component system with
  peakon and weak kink solutions

abstract:
  This paper is contributed to study the Cauchy problem of a new integrable
two-component system with peaked soliton (peakon) and weak kink solutions. We
first establish the local well-posedness result for the Cauchy problem in Besov
spaces, and then present a precise blow-up scenario and a new blow-up result
for strong solutions to the system.


title:
Signatures of the differential Klein-Nishina electronic cross section in
  Compton's quantum theory of scattering of radiation

abstract:
  A quantum theory of scattering of radiation by a stationary free electron
based on photon conception and relativistic kinematics, applying the principles
of conservation of energy and conservation of momentum was proposed by Compton
to explain the scattering of X-rays and {\gamma}-rays by light elements. The
relativistic differential cross-section for the Compton scattering of a photon
by a stationary free electron was formulated by Klein and Nishina using Dirac's
relativistic theory of electrons, and has been verified experimentally, when
the binding energy of the electron is negligible compared to the incident
photon energy. Here we show that the energy of scattered photons, and kinetic
energy of recoiled electrons obtained from Compton's quantum theory of
scattering of radiation, show a degree of matching (that increases with the
increase of incident photon energy as quantified by chi-square test) with the
differential Klein-Nishina electronic cross section per electron per unit solid
angle for the scattering of an unpolarized photon by a stationary free electron
when appropriate normalizations are invoked. There is a high degree of matching
in a regime where the total electronic Klein-Nishina cross section for the
Compton scattering on a free stationary electron scales as the inverse of the
incident photon energy and the contribution of the electro-magnetic interaction
to differential electronic cross section diminishes. Our results have
significant implications to the foundations of quantum mechanics and to the
understanding of the mechanisms of photon-electron interactions in the Compton
scattering.


title: Far-Ultraviolet Observations of Outflows from IR-Luminous Galaxies

abstract:
  We obtained medium-resolution ultraviolet (UV) spectra between 1150 and 1450
Angstroms of the four UV-bright, infrared (IR)-luminous starburst galaxies IRAS
F08339+6517, NGC 3256, NGC 6090, and NGC 7552 using the Cosmic Origins
Spectrograph onboard the Hubble Space Telescope. The selected sightlines
towards the starburst nuclei probe the properties of the recently formed
massive stars and the physical conditions in the starburst-driven galactic
superwinds. Despite being metal-rich and dusty, all four galaxies are strong
Lyman-alpha emitters with equivalent widths ranging between 2 and 13 Angstroms.
The UV spectra show strong P Cygni-type high-ionization features indicative of
stellar winds and blueshifted low-ionization lines formed in the interstellar
and circumgalactic medium. We detect outflowing gas with bulk velocities of
about 400 km/s and maximum velocities of almost 900 km/s. These are among the
highest values found in the local universe and comparable to outflow velocities
found in luminous Lyman-break galaxies at intermediate and high redshift. The
outflow velocities are unlikely to be high enough to cause escape of material
from the galactic gravitational potential. However, the winds are significant
for the evolution of the galaxies by transporting heavy elements from the
starburst nuclei and enriching the galaxy halos. The derived mass outflow rates
of ~100 Msol/yr are comparable to, or even higher than the star-formation
rates. The outflows can quench star formation and ultimately regulate the
starburst as has been suggested for high-redshift galaxies.


title:
Using XFELs for Probing of Complex Interaction Dynamics of Ultra-Intense
  Lasers with Solid Matter

abstract:
  We demonstrate the potential of X-ray free-electron lasers (XFEL) to
advancethe understanding of complex plasma dynamics by allowing for the first
time nanometer and femtosecond resolution at the same time in plasma
diagnostics. Plasma phenomena on such short timescales are of high relevance
for many fields of physics, in particular in the ultra-intense ultra-short
laser interaction with matter. Highly relevant yet only partially understood
phenomena may become directly accessible in experiment. These include
relativistic laser absorption at solid targets, creation of energetic electrons
and electron transport in warm dense matter, including the seeding and
development of surface and beam instabilities, ambipolar expansion, shock
formation, and dynamics at the surfaces or at buried layers.
  We demonstrate the potentials of XFEL plasma probing for high power laser
matter interactions using exemplary the small angle X-ray scattering technique,
focusing on general considerations for XFEL probing.


title:
Anisotropic effective higher-order response of heterogeneous Cauchy
  elastic materials

abstract:
  The homogenization results obtained by Bacca et al. (Homogenization of
heterogeneous Cauchy-elastic materials leads to Mindlin second-gradient
elasticity. Part I: Closed form expression for the effective higher-order
constitutive tensor. arXiv:1305.2365 Submitted, 2013), to define effective
second-gradient elastic materials from heterogeneous Cauchy elastic solids, are
extended here to the case of phases having non-isotropic tensors of inertia. It
is shown that the nonlocal constitutive tensor for the homogenized material
depends on both the inertia properties of the RVE and the difference between
the effective and the matrix local elastic tensors. Results show that: (i.) a
composite material can be designed to result locally isotropic but nonlocally
orthotropic; (ii.) orthotropic nonlocal effects are introduced when a dilute
distribution of aligned elliptical holes and, in the limit case, of cracks is
homogenized.


title: Quantum-statistics-induced flow patterns in driven ideal Fermi gases

abstract:
  While classical or quantum interacting liquids become turbulent under
sufficiently strong driving, it is not obvious what flow pattern an ideal
quantum gas develops under similar conditions. Unlike classical noninteracting
particles which exhibit rather trivial flow, ideal fermions have to satisfy the
exclusion principle, which acts as a form of collective repulsion. We thus
study the flow of an ideal Fermi gas as it is driven out of a narrow orifice of
width comparable to the Fermi wavelength, employing both a microcanonical
approach to transport, and solving a Lindblad equation for Markovian driving
leads. Both methods are in good agreement and predict an outflowing current
density with a complex microscopic pattern of vorticity in the steady state.
Applying a bias of the order of the chemical potential results in a short-range
correlated antiferromagnetic vorticity pattern, corresponding to local moments
of the order of a tenth of a magneton, $e\hbar/2m$, if the fermions are
charged. The latter may be detectable by magnetosensitive spectroscopy in
strongly driven cold gases (atoms) or clean electronic nanostructures
(electrons).

categories: cond-mat.quant-gas cond-mat.str-el physics.flu-dyn quant-ph


title:
Typical versus averaged overlap distribution in Spin-Glasses : Evidence
  for the droplet scaling theory

abstract:
  We consider the statistical properties over disordered samples of the overlap
distribution $P_{\cal J}(q)$ which plays the role of an order parameter in
spin-glasses. We show that near zero temperature (i) the {\it typical} overlap
distribution is exponentially small in the central region of $-1<q<1$: $
P^{typ}(q) = e^{\bar{\ln P_{\cal J}(q)}} \sim e^{- \beta N^{\theta} \phi(q)} $,
where $\theta$ is the droplet exponent defined here with respect to the total
number $N$ of spins (in order to consider also fully connected models where the
notion of length does not exist); (ii) the rescaled variable $v = - (\ln
P_{\cal J}(q))/N^{\theta}$ remains an O(1) random positive variable describing
sample-to sample fluctuations; (iii) the averaged distribution $\bar{P_{\cal
J}(q)} $ is non-typical and dominated by rare anomalous samples. Similar
statements hold for the cumulative overlap distribution $I_{\cal J}(q_0) \equiv
\int_{0}^{q_0} dq P_{\cal J}(q) $. These results are derived explicitly for the
spherical mean-field model with $\theta=1/3$, $\phi(q)=1-q^2 $, and the random
variable $v$ corresponds to the rescaled difference between the two largest
eigenvalues of GOE random matrices. Then we compare numerically the typical and
averaged overlap distributions for the long-ranged one-dimensional Ising
spin-glass with random couplings decaying as $J(r) \propto r^{-\sigma}$ for
various values of the exponent $\sigma$, corresponding to various droplet
exponents $\theta(\sigma)$, and for the mean-field SK-model (corresponding
formally to the $\sigma=0$ limit of the previous model). Our conclusion is that
future studies on spin-glasses should measure the {\it typical} values of the
overlap distribution or of the cumulative overlap distribution to obtain
clearer conclusions on the nature of the spin-glass phase.


title:
A data-driven analysis to question epidemic models for citation cascades
  on the blogosphere

abstract:
  Citation cascades in blog networks are often considered as traces of
information spreading on this social medium. In this work, we question this
point of view using both a structural and semantic analysis of five months
activity of the most representative blogs of the french-speaking
community.Statistical measures reveal that our dataset shares many features
with those that can be found in the literature, suggesting the existence of an
identical underlying process. However, a closer analysis of the post content
indicates that the popular epidemic-like descriptions of cascades are
misleading in this context.A basic model, taking only into account the behavior
of bloggers and their restricted social network, accounts for several important
statistical features of the data.These arguments support the idea that
citations primary goal may not be information spreading on the blogosphere.


title: Overlap fluctuations in glass-forming liquids

abstract:
  We analyse numerically thermal fluctuations of the static overlap between
equilibrium configurations in a glass-forming liquid approaching the glass
transition. We find that the emergence of slow dynamics near the onset
temperature correlates with the development of non-Gaussian probability
distributions of overlap fluctuations, measured using both annealed and
quenched definitions. Below a critical temperature, a thermodynamic field
conjugate to the overlap induces a first-order phase transition, whose
existence we numerically demonstrate in the annealed case. These results
establish that the approach to the glass transition is accompanied by profound
changes in the nature of thermodynamic fluctuations, deconstructing the view
that glassy dynamics occurs with little structural evolution.


title:
Magnetic Susceptibility and Landau Diamagnetism of Quantum Collisional
  Maxwellian Plasmas

abstract:
  With the use of correct expression of the electric conductivity of quantum
collisional plasmas (A. V. Latyshev and A. A. Yushkanov, {\it Transverse
electrical conductivity of a quantum collisional plasma in the Mermin
approach}. - Theor. and Math. Phys., {\bf 175}(1): 559-569 (2013)) the kinetic
description of a magnetic susceptibility is obtained and the formula for
calculation of Landau diamagnetism is deduced.


title: Teleporting photonic qudits using multimode quantum scissors

abstract:
  Teleportation plays an important role in the communication of quantum
information between the nodes of a quantum network and is viewed as an
essential ingredient for long-distance Quantum Cryptography. We describe a
method to teleport the quantum information carried by a photon in a
superposition of a number $d$ of light modes (a "qudit") by the help of $d$
additional photons based on transcription. A qudit encoded into a single
excitation of $d$ light modes (in our case Laguerre-Gauss modes which carry
orbital angular momentum) is transcribed to $d$ single-rail photonic qubits,
which are spatially separated. Each single-rail qubit consists of a
superposition of vacuum and a single photon in each one of the modes. After
successful teleportation of each of the $d$ single-rail qubits by means of
"quantum scissors" they are converted back into a qudit carried by a single
photon which completes the teleportation scheme.


title: Sharing a Reward Based on Peer Evaluations

abstract:
  We study a problem where a group of agents has to decide how some fixed value
should be shared among them. We are interested in settings where the share that
each agent receives is based on how that agent is evaluated by other members of
the group, where highly regarded agents receive a greater share compared to
agents that are not well regarded. We introduce two mechanisms for determining
agents' shares: the peer-evaluation mechanism, where each agent gives a direct
evaluation for every other member of the group, and the peer-prediction
mechanism, where each agent is asked to report how they believe group members
will evaluate a particular agent. The sharing is based on the provided
information. While both mechanisms are individually rational, the first
mechanism is strategy-proof and budget-balanced, but it can be collusion-prone.
Further, the second mechanism is collusion-resistant and incentive-compatible.


title: Review on Superconducting Materials

abstract:
  Short review of the topical comprehension of the superconductor materials
classes Cuprate High-Temperature Superconductors, other oxide superconductors,
Iron-based Superconductors, Heavy-Fermion Superconductors, Nitride
Superconductors, Organic and other Carbon-based Superconductors and Boride and
Borocarbide Superconductors, featuring their present theoretical understanding
and their aspects with respect to technical applications.


title:
Genuine fidelity gaps associated with a sequential decomposition of
  genuinely entangling isometry and unitary operations

abstract:
  We draw attention to the existence of "genuine" fidelity gaps in an
ancilla-assisted sequential decomposition of genuinely entangling isometry and
unitary operations of quantum computing. The gaps arise upon a bipartite
decomposition of a multiqubit operation in a one-way sequential recipe in which
an ancillary system interacts locally and only once with each qubit in a row.
Given the known "no-go" associated with such a theoretically and experimentally
desirable decomposition, various figures of merit are introduced to analyze the
optimal "fidelity" with which an arbitrary genuinely entangling operation may
admit such a sequential decomposition. An efficient variational
matrix-product-operator (VMPO) protocol is invoked in order to obtain
numerically the minimal values of the fidelity gaps incurred upon sequential
decomposition of genuine entanglers. We term the values of the gaps so obtained
genuine in the light of possible connections to the concept of the genuine
multipartite entanglement and since they are independent of the ancilla
dimension and the initial states the associated unitaries act upon.


title:
Improved Bounds on the Phase Transition for the Hard-Core Model in
  2-Dimensions

abstract:
  For the hard-core lattice gas model defined on independent sets weighted by
an activity $\lambda$, we study the critical activity $\lambda_c(\mathbb{Z}^2)$
for the uniqueness/non-uniqueness threshold on the 2-dimensional integer
lattice $\mathbb{Z}^2$. The conjectured value of the critical activity is
approximately $3.796$. Until recently, the best lower bound followed from
algorithmic results of Weitz (2006). Weitz presented an FPTAS for approximating
the partition function for graphs of constant maximum degree $\Delta$ when
$\lambda<\lambda_c(\mathbb{T}_\Delta)$ where $\mathbb{T}_\Delta$ is the
infinite, regular tree of degree $\Delta$. His result established a certain
decay of correlations property called strong spatial mixing (SSM) on
$\mathbb{Z}^2$ by proving that SSM holds on its self-avoiding walk tree
$T_{\mathrm{saw}}^\sigma(\mathbb{Z}^2)$ where $\sigma=(\sigma_v)_{v\in
\mathbb{Z}^2}$ and $\sigma_v$ is an ordering on the neighbors of vertex $v$. As
a consequence he obtained that $\lambda_c(\mathbb{Z}^2)\geq\lambda_c(
\mathbb{T}_4) = 1.675$. Restrepo et al. (2011) improved Weitz's approach for
the particular case of $\mathbb{Z}^2$ and obtained that
$\lambda_c(\mathbb{Z}^2)>2.388$. In this paper, we establish an upper bound for
this approach, by showing that, for all $\sigma$, SSM does not hold on
$T_{\mathrm{saw}}^\sigma(\mathbb{Z}^2)$ when $\lambda>3.4$. We also present a
refinement of the approach of Restrepo et al. which improves the lower bound to
$\lambda_c(\mathbb{Z}^2)>2.48$.


title: The Stringy Instanton Partition Function

abstract:
  We perform an exact computation of the gauged linear sigma model associated
to a D1-D5 brane system on a resolved A_1 singularity. This is accomplished via
supersymmetric localization on the blown-up two-sphere. We show that in the
blow-down limit C^2/Z_2 the partition function reduces to the Nekrasov
partition function evaluating the equivariant volume of the instanton moduli
space. For finite radius we obtain a tower of world-sheet instanton
corrections, that we identify with the equivariant Gromov-Witten invariants of
the ADHM moduli space. We show that these corrections can be encoded in a
deformation of the Seiberg-Witten prepotential. From the mathematical
viewpoint, the D1-D5 system under study displays a twofold nature: the
D1-branes viewpoint captures the equivariant quantum cohomology of the ADHM
instanton moduli space in the Givental formalism, and the D5-branes viewpoint
is related to higher rank equivariant Donaldson-Thomas invariants of P^1 x C^2.


title: Discrete Dynamical Modeling and Analysis of the R-S Flip-Flop Circuit

abstract:
  A simple discrete planar dynamical model for the ideal (logical) R-S
flip-flop circuit is developed with an eye toward mimicking the dynamical
behavior observed for actual physical realizations of this circuit. It is shown
that the model exhibits most of the qualitative features ascribed to the R-S
flip-flop circuit, such as an intrinsic instability associated with unit set
and reset inputs, manifested in a chaotic sequence of output states that tend
to oscillate among all possible output states, and the existence of periodic
orbits of arbitrarily high period that depend on the various intrinsic system
parameters. The investigation involves a combination of analytical methods from
the modern theory of discrete dynamical systems, and numerical simulations that
illustrate the dazzling array of dynamics that can be generated by the model.
Validation of the discrete model is accomplished by comparison with certain
Poincar\'e map like representations of the dynamics corresponding to
three-dimensional differential equation models of electrical circuits that
produce R-S flip-flop behavior.


title:
Standard Model predictions for B -> Kll with form factors from lattice
  QCD

abstract:
  We calculate, for the first time using unquenched lattice QCD form factors,
the Standard Model differential branching fractions $dB/dq^2(B \to Kll)$ for
$l=e, \mu, \tau$ and compare with experimental measurements by Belle, BABAR,
CDF, and LHCb. We report on $\mathcal{B}(B \to Kll)$ in $q^2$ bins used by
experiment and predict $\mathcal{B}(B \to K \tau \tau) = (1.44 \pm 0.15)
10^{-7}$. We also calculate the ratio of branching fractions $R^\mu_e =
1.00023(63)$ and predict $R^\tau_l = 1.159(40)$, for $l=e, \mu$. Finally, we
calculate the "flat term" in the angular distribution of the differential decay
rate $F_H^{e, \mu, \tau}$ in experimentally motivated $q^2$ bins.


title: Schr\"odinger operators with complex singular potentials

abstract:
  We study one-dimensional Schr\"{o}dinger operators $\mathrm{S}(q)$ on the
space $L^{2}(\mathbb{R})$ with potentials $q$ being complex-valued generalized
functions from the negative space $H_{unif}^{-1}(\mathbb{R})$. Particularly the
class $H_{unif}^{-1}(\mathbb{R})$ contains periodic and almost periodic
$H_{loc}^{-1}(\mathbb{R})$-functions. We establish an equivalence of the
various definitions of the operators $\mathrm{S}(q)$, investigate their
approximation by operators with smooth potentials from the space
$L_{unif}^{1}(\mathbb{R})$ and prove that the spectrum of each operator
$\mathrm{S}(q)$ lies within a certain parabola.


title: Peixoto's Structural Stability Theorem: The One-dimensional Version

abstract:
  Peixoto's structural stability and density theorems represent milestones in
the modern theory of dynamical systems and their applications. Despite the
importance of these theorems, they are often treated rather superficially, if
at all, in upper level undergraduate courses on dynamical systems or
differential equations. This is mainly because of the depth and length of the
proofs. In this note/module, we formulate and prove the one-dimensional analogs
of Peixoto's theorems in an intuitive and fairly simple way using only concepts
and results that for the most part should be familiar to upper level
undergraduate students in the mathematical sciences or related fields. The
intention is to provide students who may be interested in further study in
dynamical systems with an accessible one-dimensional treatment of structural
stability theory that should help make Peixoto's theorems and their more recent
generalizations easier to appreciate and understand.


title:
Gross fibrations, SYZ mirror symmetry, and open Gromov-Witten invariants
  for toric Calabi-Yau orbifolds

abstract:
  For a toric Calabi-Yau (CY) orbifold $\mathcal{X}$ whose underlying toric
variety is semi-projective, we construct and study a non-toric Lagrangian torus
fibration on $\mathcal{X}$, which we call the Gross fibration. We apply the
Strominger-Yau-Zaslow (SYZ) recipe to the Gross fibration of $\mathcal{X}$ to
construct its mirror with the instanton corrections coming from genus 0 open
orbifold Gromov-Witten (GW) invariants, which are virtual counts of holomorphic
orbi-disks in $\mathcal{X}$ bounded by fibers of the Gross fibration.
  We explicitly evaluate all these invariants by first proving an open/closed
equality and then employing the toric mirror theorem for suitable toric
(partial) compactifications of $\mathcal{X}$. Our calculations are then applied
to
  (1) prove a conjecture of Gross-Siebert on a relation between genus 0 open
orbifold GW invariants and mirror maps of $\mathcal{X}$ -- this is called the
open mirror theorem, which leads to an enumerative meaning of mirror maps, and
  (2) demonstrate how open (orbifold) GW invariants for toric CY orbifolds
change under toric crepant resolutions -- an open analogue of Ruan's crepant
resolution conjecture.


title: Multiply partition regular matrices

abstract:
  Let $A$ be a finite matrix with rational entries. We say that $A$ is {\it
doubly image partition regular\/} if whenever the set ${\mathbb N}$ of positive
integers is finitely coloured, there exists $\vec x$ such that the entries of
$A\vec x$ are all the same colour (or {\it monochromatic\/}) and also, the
entries of $\vec x$ are monochromatic. Which matrices are doubly image
partition regular?
  More generally, we say that a pair of matrices $(A,B)$, where $A$ and $B$
have the same number of rows, is {\it doubly kernel partition regular\/} if
whenever ${\mathbb N}$ is finitely coloured, there exist vectors $\vec x$ and
$\vec y$, each monochromatic, such that $A \vec x + B \vec y = 0$. There is an
obvious sufficient condition for the pair $(A,B)$ to be doubly kernel partition
regular, namely that there exists a positive rational $c$ such that the matrix
$M=(\begin{array}{ccccc}A&cB\end{array})$ is kernel partition regular. (That
is, whenever ${\mathbb N}$ is finitely coloured, there exists monochromatic
$\vec x$ such that $M \vec x=\vec 0$.) Our aim in this paper is to show that
this sufficient condition is also necessary. As a consequence we have that a
matrix $A$ is doubly image partition regular if and only if there is a positive
rational $c$ such that the matrix $(\begin{array}{lr}A&cI\end{array})$ is
kernel partition regular, where $I$ is the identity matrix of the appropriate
size.
  We also prove extensions to the case of several matrices.


title: Remarks on Schr\"odinger operators with singular matrix potentials

abstract:
  In this paper the asymmetric generalization of the Glazman-Povzner-Wienholtz
theorem is proved for one-dimensional Schr\"{o}dinger operators with strongly
singular matrix potentials from the space $H_{loc}^{-1}(\mathbb{R},
\mathbb{C}^{m\times m})$. This result is new in the scalar case as well.


title:
Phase separation in quasi incompressible fluids: Cahn-Hilliard model in
  the Cattaneo-Maxwell framework

abstract:
  In this paper we propose a mathematical model of phase separation for a
quasi-incompressible binary mixture where the spinodal decomposition is induced
by an heat flux governed by the Cattaneo-Maxwell equation. As usual, the phase
separation is considered in the framework of phase field modeling so that the
transition is described by an additional field, the concentration c. The
evolution of concentration is described by the Cahn-Hilliard equation and in
our model is coupled with the Navier-Stokes equation. Since thermal effect are
included, the whole set of evolution equations is set up for the velocity, the
concentration, the temperature and the heat flux. The model is compatible with
thermodynamics and a maximum theorem holds.


title:
DCaaS: Data Consistency as a Service for Managing Data Uncertainty on
  the Clouds

abstract:
  Ensuring data correctness over partitioned distributed database systems is a
classical problem. Classical solutions proposed to solve this problem are
mainly adopting locking or blocking techniques. These techniques are not
suitable for cloud environments as they produce terrible response times; due to
the long latency and faultiness of wide area network connections among cloud
datacenters. One way to improve performance is to restrict access of
users-bases to specific datacenters and avoid data sharing between datacenters.
However, conflicts might appear when data is replicated between datacenters;
nevertheless change propagation timeliness is not guaranteed. Such problems
created data uncertainty on cloud environments. Managing data uncertainty is
one of the main obstacles for supporting global distributed transactions on the
clouds. To overcome this problem, this paper proposes an quota-based approach
for managing data uncertainty on the clouds that guarantees global data
correctness without global locking or blocking. To decouple service developers
from the hassles of managing data uncertainty, we propose to use a new platform
service (i.e. Data Consistency as a Service (DCaaS)) to encapsulate the
proposed approach. DCaaS service also ensures SaaS services cloud portability,
as it works as a cloud adapter between SaaS service instances. Experiments show
that proposed approach realized by the DCaaS service provides much better
response time when compared with classical locking and blocking techniques.


title: Evolutionary Approach for the Containers Bin-Packing Problem

abstract:
  This paper deals with the resolution of combinatorial optimization problems,
particularly those concerning the maritime transport scheduling. We are
interested in the management platforms in a river port and more specifically in
container organisation operations with a view to minimizing the number of
container rehandlings. Subsequently, we rmeet customers delivery deadlines and
we reduce ship stoppage time In this paper, we propose a genetic algorithm to
solve this problem and we present some experiments and results.


title:
Search for weakly interacting sub-eV particles with the OSQAR
  laser-based experiment: results and perspectives

abstract:
  Recent theoretical and experimental studies highlight the possibility of new
fundamental particle physics beyond the Standard Model that can be probed by
sub-eV energy experiments. The OSQAR photon regeneration experiment looks for
"Light Shining through a Wall" (LSW) from the quantum oscillation of optical
photons into "Weakly Interacting Sub-eV Particles" (WISPs), like axion or
axion-like particles (ALPs), in a 9 T transverse magnetic field over the
unprecedented length of $2 \times 14.3$ m. No excess of events has been
detected over the background. The di-photon couplings of possible new light
scalar and pseudo-scalar particles can be constrained in the massless limit to
be less than $8.0\times10^{-8}$ GeV$^{-1}$. These results are very close to the
most stringent laboratory constraints obtained for the coupling of ALPs to two
photons. Plans for further improving the sensitivity of the OSQAR experiment
are presented.


title: Fourier-Laplace transform and isomonodromic deformations

abstract:
  Using the Fourier-Laplace transform, we describe the isomonodromy equations
for meromorphic connections on the Riemann sphere with unramified irregular
singularities as those for connections with a (possibly ramified) irregular
singularity and a regular singularity. This generalizes some results of Harnad
and Woodhouse.


title: Analytic expanding circle maps with explicit spectra

abstract:
  We show that for any $\lambda \in \mathbb{C}$ with $|\lambda|<1$ there exists
an analytic expanding circle map such that the eigenvalues of the associated
transfer operator (acting on holomorphic functions) are precisely the
nonnegative powers of $\lambda$ and $\bar{\lambda}$. As a consequence we obtain
a counterexample to a variant of a conjecture of Mayer on the reality of
spectra of transfer operators.


title:
$\Lambda_b \to p l^- \bar{\nu}$ form factors from lattice QCD with
  static b quarks

abstract:
  We present a lattice QCD calculation of form factors for the decay $\Lambda_b
\to p \mu^- \bar{\nu}$, which is a promising channel for determining the CKM
matrix element $|V_{ub}|$ at the Large Hadron Collider. In this initial study
we work in the limit of static b quarks, where the number of independent form
factors reduces to two. We use dynamical domain-wall fermions for the light
quarks, and perform the calculation at two different lattice spacings and at
multiple values of the light-quark masses in a single large volume. Using our
form factor results, we calculate the $\Lambda_b \to p \mu^- \bar{\nu}$
differential decay rate in the range $14 GeV^2 \leq q^2 \leq q^2_{max}$, and
obtain the integral $\int_{14 GeV^2}^{q^2_{max}} [d\Gamma/dq^2] dq^2 /
|V_{ub}|^2 = 15.3 \pm 4.2 ps^{-1}$. Combined with future experimental data,
this will give a novel determination of $|V_{ub}|$ with about 15\% theoretical
uncertainty. The uncertainty is dominated by the use of the static
approximation for the b quark, and can be reduced further by performing the
lattice calculation with a more sophisticated heavy-quark action.


title: Secure multiparty quantum computation based on bit commitment

abstract:
  This paper studies secure multiparty quantum computation (SMQC) without
nonlocal measurements. Firstly, this task is reduced to secure two-party
quantum computation of nonlocal controlled-NOT (NL-CNOT) gate. Then, in the
passive adversaries model, the secure computation of NL-CNOT is reduced to bit
commitment. Thus, a SMQC scheme can be constructed based on bit commitment.
This scheme does not depend on trusted third party, and is secure in the
passive adversaries model. It is also pointed out that a vulnerability exists
in any secure two-party quantum computation protocol of NL-CNOT gate.


title:
Adaptive Fixed Priority End-To-End Imprecise Scheduling In Distributed
  Real Time Systems

abstract:
  In end-to-end distributed real time systems, a task may be executed
sequentially on different processors. The end-toend task response time must not
exceed the end-to-end task deadline to consider the task a schedulable task. In
transient over load periods, deadlines may be missed or processors may
saturate. The imprecise computation technique is a way to overcome the
mentioned problems by trading off precision and timeliness. We developed an
imprecise integrated framework for scheduling fixed priority end-to-end tasks
in distributed real time systems by extending an existing integrated framework
for the same problem. We devised a new priority assignment scheme called global
mandatory relevance scheme to meet the concept of imprecise computation. We
devised an algorithm for processor utilization adjustment, this algorithm
decreases the processor load when the processor utilization is greater than
one. Also we extended the schedulability analysis algorithms presented in the
old framework to allow adaptive priority assignment and to meet imprecise
computation concept. Simulation results showed that our new framework is more
dependable and predictable than the existing framework over transient overload
periods.


title: On supercompactness and the continuum function

abstract:
  Given a cardinal $\kappa$ that is $\lambda$-supercompact for some regular
cardinal $\lambda\geq\kappa$ and assuming $\GCH$, we show that one can force
the continuum function to agree with any function
$F:[\kappa,\lambda]\cap\REG\to\CARD$ satisfying $\forall\alpha,\beta\in\dom(F)$
$\alpha<\cf(F(\alpha))$ and $\alpha<\beta$ $\implies$ $F(\alpha)\leq F(\beta)$,
while preserving the $\lambda$-supercompactness of $\kappa$ from a hypothesis
that is of the weakest possible consistency strength, namely, from the
hypothesis that there is an elementary embedding $j:V\to M$ with critical point
$\kappa$ such that $M^\lambda\subseteq M$ and $j(\kappa)>F(\lambda)$. Our
argument extends Woodin's technique of surgically modifying a generic filter to
a new case: Woodin's key lemma applies when modifications are done on the range
of $j$, whereas our argument uses a new key lemma to handle modifications done
off of the range of $j$ on the ghost coordinates. This work answers a question
of Friedman and Honzik [FH2012]. We also discuss several related open
questions.


title: Nonequilibrium identities and response theory for dissipative particles

abstract:
  We derive some nonequilibrium identities such as the integral fluctuation
theorem and the Jarzynski equality starting from a nonequilibrium state for
dissipative classical systems. Thanks to the existence of the integral
fluctuation theorem we can naturally introduce an entropy-like quantity for
dissipative classical systems in far from equilibrium states.
  We also derive the generalized Green-Kubo formula as a nonlinear response
theory for a steady dynamics around a nonequilibrium state. We numerically
verify the validity of the derived formulas for sheared frictionless granular
particles.


title: Climate variability according to triple saros gravity cycles

abstract:
  I describe a climate model which corresponds directly to eclipse cycles. The
theory is based upon a similarity between the 54 year triple saros eclipse
period and the periodicity of drought. I argue that eclipse shadows are an
indication of gravity cycles, and that variable lunar gravitation is the most
significant aspect of the eclipse process. I reinforce the idea that lunar
gravitational forcing has a profound effect on the water vapor in Earth's
atmosphere, and can affect the density and location of clouds. I explore the
possibility that decadal variability of ocean surface levels may be explained
by triple saros gravity cycles. I point out that lunar gravitation was excluded
from the most significant climate report of 2007, and that climate data
contradictions have been overlooked by researchers. I focus on the value of
data that has not been aggregated into global averages. I touch upon the
history of global warming, and I offer predictions based upon 54 year climate
periodicity.


title:
Elastic pp scattering from the optical point to past the dip: an
  empirical parametrization from ISR to LHC

abstract:
  We describe the main features of recent LHC data on elastic pp scattering
through a simple parametrization to the amplitude, inspired by a model proposed
by Barger and Phillips in 1973, comprising of two exponentials with a relative
phase. Despite its simplicity, this parameterization reproduces two essential
aspects of the elastic differential cross section, the well known precipitous
descent in the forward direction and a sharp `dip' structure. To include a
complete description of data sets near -t=0, we correct the original
parametrization. We examine two possibilities, the presence of the two-pion
threshold singularity or a multiplicative factor reflecting the proton form
factor. We find good descriptions of LHC7 and ISR data in either case. The form
factor model allows simple predictions for higher energies through asymptotic
theorems and asymptotic sum rules in impact parameter space. We present
predictions for this model at higher LHC energies, which can be used to test
whether asymptotia is reached. The black disk limit in this model is seen to be
reached only for energies near 10^6 TeV.


title: Subfield Effects on the Core of Coauthors

abstract:
  It is examined whether the number ($J$) of (joint) publications of a "main
scientist" with her/his coauthors ranked according to rank ($r$) importance,
i.e. $ J \propto 1/r $, as found by Ausloos [1] still holds for subfields, i.e.
when the "main scientist" has worked on different, sometimes overlapping,
subfields. Two cases are studied. It is shown that the law holds for large
subfields. As shown, in an Appendix, is also useful to combine small topics
into large ones for better statistics. It is observed that the sub-cores are
much smaller than the overall coauthor core measure. Nevertheless, the
smallness of the core and sub-cores may imply further considerations for the
evaluation of team research purposes and activities.


title: Bispectrality for the quantum open Toda chain

abstract:
  An alternative to Babelon's (2003) construction of dual variables for the
quantum open Toda chain is proposed that is based on the 2x2 Lax matrix and the
corresponding quadratic R-matrix algebra.


title: Kolmogorov Equations for Randomly Perturbed Generalized Newtonian Fluids

abstract:
  We consider incompressible generalized Newtonian fluids in two space
dimensions perturbed by an additive Gaussian noise. The velocity field of such
a fluid obeys a stochastic partial differential equation with fully nonlinear
drift due to the dependence of viscosity on the shear rate. In particular, we
assume that the extra stress tensor is of power law type, i.\,e. a polynomial
of degree $p-1$, $p \in (1,2)$, i.\,e. the shear thinning case. We prove that
the associated Kolmogorov operator $K$ admits at least one infinitesimally
invariant measure $\mu$ satisfying certain exponential moment estimates.
Moreover, $K$ is $L^2$-unique w.\,r.\,t. $\mu$ provided $p \in (p^\ast,2)$,
where $p^\ast$ is the second root of $p^3 - 8p^2 + 14p -6 =0$, approximately
$p^\ast \approx 1.60407$.


title:
Gauge symmetry and background independence: Should the proton spin
  decomposition be path independent?

abstract:
  Exploring the similarities between the Chen \emph{et al.} approach, where
physical and gauge degrees of freedom of the gauge potential are explicitly
separated, and the background field method, we provide an alternative point of
view to the proton spin decomposition issue. We show in particular that the
gauge symmetry can be realized in two different ways, and discuss the relations
between the concepts of path dependence, Stueckelberg dependence and background
dependence. Finally, we argue that path/Stueckelberg/background-dependent
decompositions of the proton spin are in principle measurable and therefore
physically meaningful.


title: Pulsating Strings With Angular Momenta

abstract:
  We derive the energy of pulsating string, as function of oscillation number
and angular momenta, which oscillates in AdS3 with an extra angular momentum
along S1. We find similar solutions for the strings oscillating in S3 in
addition to extra angular momentum. Further we generalize the result of the
oscillating strings in Anti de-Sitter space in the presence of both spin and
angular momentum in AdS5 x S1.


title: Simple Zeros Of The Zeta Function

abstract:
  This note studies the Laurent series of the inverse zeta function
$1/\zeta(s)$ at any fixed nontrivial zero $\rho$ of the zeta function
$\zeta(s)$, and its connection to the simplicity of the nontrivial zeros.


title: Physical properties of Co/n-Ge Schottky contacts

abstract:
  To investigate the role of the interface state on the physical properties of
Schottky contacts, Co/n-Ge Schottky diodes that have undergone various cleaning
methods (HF etching and in-situ thermal cleaning) were studied by Transmission
Electron Microscopy (TEM), Deep-level Transient Spectroscopy (DLTS) and by a
detailed analysis of the temperature dependence of the diodes characteristics.
It is shown that Schottky barrier height characteristics are sensitive to the
nature of the interface. The strongest Fermi level pinning and the highest
spatial inhomogeneities are observed for intimate metal/semiconductor contacts.
The presence of a thin oxide interlayer, even of Ge native oxide, allows the
Fermi level to be released towards the conduction band and leads to more
homogeneous contacts. Finally our results suggest that a pure GeO2 oxide
interlayer should present a better depinning efficiency than the native Ge
oxide.


title:
Ultraproducts, QWEP von Neumann Algebras, and the Effros-Mar\'echal
  Topology

abstract:
  Based on the analysis on the Ocneanu/Groh-Raynaud ultraproducts and the
Effros-Mar\'echal topology on the space vN(H) of von Neumann algebras acting on
a separable Hilbert space H, we show that for a von Neumann algebra M in vN(H),
the following conditions are equivalent: (1) M has the Kirhcberg's quotient
weak expectation property (QWEP). (2) M is in the closure of the set F_{inj of
injective factors on H with respect to the Effros-Mar\'echal topology. (3) M
admits an embedding i into the Ocneanu ultrapower R_{infty}^{omega} of the
injective III_1 factor R_{\infty} with a normal faithful conditional
expectation epsilon: R_{infty}^{omega} to i(M). (4) For every epsilon>0,
natural number n, and xi_1,...,xi_n in P_M^{natural}, there is a natural number
k and a_1,...,a_nin M_k(C)_+, such that |<xi_i,xi_j>-tr_k(a_ia_j)|<epsilon
(1<=i,j<=n) holds, where tr_k is the tracial state on M_k(C), and P_M^{natural}
is the natural cone in the standard form of M.


title: The Ramsey number of the clique and the hypercube

abstract:
  The Ramsey number r(K_s,Q_n) is the smallest positive integer N such that
every red-blue colouring of the edges of the complete graph K_N on N vertices
contains either a red n-dimensional hypercube, or a blue clique on s vertices.
Answering a question of Burr and Erd\H{o}s from 1983, and improving on recent
results of Conlon, Fox, Lee and Sudakov, and of the current authors, we show
that r(K_s,Q_n) = (s-1) (2^n - 1) + 1 for every s \in \N and every sufficiently
large n \in \N.


title: Breathing Charge Density Waves in Intrinsic Josephson Junctions

abstract:
  We demonstrate the creation of a charge density wave (CDW) along a stack of
coupled Josephson junctions in layered superconductors. Electric charge in each
superconducting layer oscillates around some average value, forming a breathing
CDW. We show the transformation of a longitudinal plasma wave to CDW in the
state corresponding to the outermost branch. Transitions between different
types of CDW's related to the inner branches of current voltage characteristics
are demonstrated. The effect of the external electromagnetic irradiation on the
states corresponding to the inner branches differs crucially from the case of
the single Josephson junction. The Shapiro steps in the IV-characteristics of
the junctions in the stack do not correspond directly to the frequency of
radiation $\omega$. The system of Josephson junctions behaves like a single
whole system: the Shapiro steps or their harmonics in the total
IV-characteristics appear at voltage $\sum V_l=N_R\frac{m}{n}\omega$, where
$V_l$ is the voltage in $l$-th junction, $N_R$ is the number of JJ in the
rotating state, and $m$ and $n$ are integer numbers.


title:
Adsorption site determination of a molecular monolayer via inelastic
  tunneling

abstract:
  We have combined scanning tunneling microscopy with inelastic electron
tunneling spectroscopy (IETS) and density functional theory (DFT) to study a
tetracyanoethylene monolayer on Ag(100). Images show that the molecules arrange
in locally ordered patterns with three non-equivalent, but undeterminable,
adsorption sites. While scanning tunneling spectroscopy only shows subtle
variations of the local electronic structure at the three different positions,
we find that vibrational modes are very sensitive to the local atomic
environment. IETS detects sizeable mode frequency shifts of the molecules
located at the three topographically detected sites, which permits us to
determine the molecular adsorption sites through identification with DFT
calculations.


title:
Habitability in Different Milky Way Stellar Environments: a Stellar
  Interaction Dynamical Approach

abstract:
  Every Galactic environment is characterized by a stellar density and a
velocity dispersion. With this information from literature, we simulated flyby
encounters for several Galactic regions, numerically calculating stellar
trajectories as well as orbits for particles in disks; our aim was to
understand the effect of typical stellar flybys on planetary (debris) disks in
the Milky Way Galaxy. For the Solar neighborhood, we examined nearby stars with
known distance, proper motions, and radial velocities. We found occurrence of a
disturbing impact to the Solar planetary disk within the next 8 Myr to be
highly unlikely; perturbations to the Oort cloud seem unlikely as well. Current
knowledge of the full phase space of stars in the Solar neighborhood, however,
is rather poor, and thus we cannot rule out the existence of a star that is
more likely to approach than those for which we have complete kinematic
information. We studied the effect of stellar encounters on planetary orbits
within the habitable zones of stars in more crowded stellar environments, such
as stellar clusters. We found that in open clusters habitable zones are not
readily disrupted; this is true if they evaporate in less than 108 years. For
older clusters the results may not be the same. We specifically studied the
case of Messier 67, one of the oldest open clusters known, and show the effect
of this environment on debris disks. We also considered the conditions in
globular clusters, the Galactic nucleus, and the Galactic bulge-bar. We
calculated the probability of whether Oort clouds exist in these Galactic
environments.


title:
Detection of (15)NNH+ in L1544: non-LTE modelling of dyazenilium
  hyperfine line emission and accurate (14)N/(15)N values

abstract:
  Samples of pristine Solar System material found in meteorites and
interplanetary dust particles are highly enriched in (15)N. Conspicuous
nitrogen isotopic anomalies have also been measured in comets, and the
(14)N/(15)N abundance ratio of the Earth is itself larger than the recognised
pre-solar value by almost a factor of two. Ion--molecules, low-temperature
chemical reactions in the proto-solar nebula have been repeatedly indicated as
responsible for these (15)N-enhancements. We have searched for (15)N variants
of the N2H+ ion in L1544, a prototypical starless cloud core which is one of
the best candidate sources for detection owing to its low central core
temperature and high CO depletion. The goal is the evaluation of accurate and
reliable (14)N/(15)N ratio values for this species in the interstellar gas. A
deep integration of the (15)NNH+ (1-0) line at 90.4 GHz has been obtained with
the IRAM 30 m telescope. Non-LTE radiative transfer modelling has been
performed on the J=1-0 emissions of the parent and (15)N-containing dyazenilium
ions, using a Bonnor--Ebert sphere as a model for the source. A high-quality
fit of the N2H+ (1--0) hyperfine spectrum has allowed us to derive a revised
value of the N2H+ column density in L1544. Analysis of the observed N(15)NH+
and (15)NNH+ spectra yielded an abundance ratio N[N(15)NH+]/N[(15)NNH+] = 1.1
+/- 0.3. The obtained (14)N/(15)N ratio is ~ 1000 +/- 200, suggestive of a
sizeable (15)N depletion in this molecular ion. Such a result is not consistent
with the prediction of present nitrogen chemical models. As chemical models
predict large (15)N fractionation of N2H+, we suggest that (15)N(14)N, or (15)N
in some other molecular form, is preferentially depleted onto dust grains.


title: Extended higher spin holography and Grassmannian models

abstract:
  We propose holographic dualities between higher spin gravity theories
extended with Chan-Paton factor on AdS_3 and a large N limit of two dimensional
Grassmannian models with and without supersymmetry. These proposals are natural
extensions of the duality without Chan-Paton factor, and the extensions are
motivated by a higher dimensional version of the duality, which implies a
possible relation to superstring theory via ABJ theory. As evidence for the
proposals, we show that the free limit of the Grassmannian models have the
higher spin symmetry expected from the dual gravity theory. Furthermore, we
construct currents in the 't Hooft limit of the supersymmetric Grassmannian
model and compare them with the currents from the bulk theory. One-loop
partition function of the supergravity theory is reproduced by the 't Hooft
limit of the Grassmannian model after decoupling a gauge sector.


title:
Quantum State Tomography with incomplete data: Maximum Entropy and
  Variational Quantum Tomography

abstract:
  Whenever we do not have an informationally complete set of measurements, the
estimate of a quantum state can not be uniquely determined. In this case, among
the density matrices compatible with the available data, it is commonly
preferred that one which is the most uncommitted with the missing information.
This is the purpose of the Maximum Entropy estimation (MaxEnt) and the
Variational Quantum Tomography (VQT). Here, we propose a variant of Variational
Quantum Tomography and show its relationship with Maximum Entropy methods in
quantum tomographies with incomplete set of measurements. We prove their
equivalence in case of eigenbasis measurements, and through numerical
simulations we stress their similar behavior. Hence, in the modified VQT
formulation we have an estimate of a quantum state as unbiased as in MaxEnt and
with the benefit that VQT can be more efficiently solved by means of linear
semidefinite programs.


title:
Reserve Requirement Analysis using a Dynamical System of a Bank based on
  Monti-Klein model of Bank's Profit Function

abstract:
  Commercial banks and other depository institutions in some countries are
required to hold in reserve against deposits made by their customers at their
Central Bank or Federal Reserve. Although some countries have been eliminated
it, this requirement is useful as one of many Central Bank's regulation made to
control rate of inflation and conditions of excess liquidity in banks which
could affect the monetary stability. The amount of this reserve is affected by
the volumes of the commercial bank's loan and deposit, and also by the bank's
Loan to Deposit Ratio (LDR) value. In this research, a dynamical system of the
volume of deposits (dD/dt) and loans (dL/dt) of a bank is constructed from the
bank profit equation by Monti-Klein. The model is implemented using the
regulation of Bank of Indonesia, and analysed in terms of the behaviour of the
solution. Based on some simplifying assumptions in this model, the results show
that eventhough the LDR values at the initial points of two solutions are the
same, the behavior of solutions will be significantly different due to
different magnitude of L and D volumes.


title:
Dynamic nuclear polarization in InGaAs/GaAs and GaAs/AlGaAs quantum dots
  under non-resonant ultra-low power optical excitation

abstract:
  We study experimentally the dependence of dynamic nuclear spin polarization
on the power of non-resonant optical excitation in two types of individual
neutral semiconductor quantum dots: InGaAs/GaAs and GaAs/AlGaAs. We show that
the mechanism of nuclear spin pumping via second order recombination of
optically forbidden (''dark'') exciton states recently reported in InP/GaInP
quantum dots [Phys. Rev. B 83, 125318 (2011)] is relevant for material systems
considered in this work. In the InGaAs/GaAs dots this nuclear spin polarization
mechanism is particularly pronounced, resulting in Overhauser shifts up to ~80
micro-eV achieved at optical excitation power ~1000 times smaller than the
power required to saturate ground state excitons. The Overhauser shifts
observed at low-power optical pumping in the interface GaAs/AlGaAs dots are
generally found to be smaller (up to ~40 micro-eV). Furthermore in GaAs/AlGaAs
we observe dot-to-dot variation and even sign reversal of the Overhauser shift
which is attributed to dark-bright exciton mixing originating from
electron-hole exchange interaction in dots with reduced symmetry. Nuclear spin
polarization degrees reported in this work under ultra-low power optical
pumping are comparable to those achieved by techniques such as resonant optical
pumping or above-gap pumping with high power circularly polarized light.
Dynamic nuclear polarization via second-order recombination of ''dark''
excitons may become a useful tool in single quantum dot applications, where
manipulation of the nuclear spin environment or electron spin is required.


title:
The distinction of turbulence from chaos -- rough dependence on initial
  data

abstract:
  I propose a new theory on the nature of turbulence: when the Reynolds number
is large, violent fully developed turbulence is due to "rough dependence on
initial data" rather than chaos which is caused by "sensitive dependence on
initial data"; when the Reynolds number is moderate, (often transient)
turbulence is due to chaos. The key in the validation of the theory is
estimating the temporal growth of the initial perturbations with the Reynolds
number as a parameter. Analytically, this amounts to estimating the temporal
growth of the norm of the derivative of the solution map of the Navier-Stokes
equations, for which here I obtain an upper bound $e^{C \sqrt{t Re} + C_1 t}$.
This bound clearly indicates that when the Reynolds number is large, the
temporal growth rate can potentially be large in short time, i.e. rough
dependence on initial data.

categories: physics.flu-dyn math-ph math.AP math.MP nlin.CD


title:
Operation and first results of the NEXT-DEMO prototype using a silicon
  photomultiplier tracking array

abstract:
  NEXT-DEMO is a high-pressure xenon gas TPC which acts as a technological
test-bed and demonstrator for the NEXT-100 neutrinoless double beta decay
experiment. In its current configuration the apparatus fully implements the
NEXT-100 design concept. This is an asymmetric TPC, with an energy plane made
of photomultipliers and a tracking plane made of silicon photomultipliers
(SiPM) coated with TPB. The detector in this new configuration has been used to
reconstruct the characteristic signature of electrons in dense gas.
Demonstrating the ability to identify the MIP and "blob" regions. Moreover, the
SiPM tracking plane allows for the definition of a large fiducial region in
which an excellent energy resolution of 1.82% FWHM at 511 keV has been measured
(a value which extrapolates to 0.83% at the xenon Qbetabeta).


title: Numerical integration of thermal noise in relativistic hydrodynamics

abstract:
  Thermal fluctuations affect the dynamics of systems near critical points, the
evolution of the early universe, and two-particle correlations in heavy-ion
collisions. For the latter, numerical simulations of nearly-ideal, relativistic
fluids are necessary. The correlation functions of noise in relativistic fluids
are calculated, stochastic integration of the noise in 3+1-dimensional viscous
hydrodynamics is implemented, and the effect of noise on observables in
heavy-ion collisions is discussed. Thermal fluctuations will cause significant
variance in the event-by-event distributions of integrated v2 while changing
average values even when using the same initial conditions, suggesting that
including thermal noise will lead to refitting of the hydrodynamical parameters
with implications for understanding the physics of hot QCD.


title: A polynomial embedding of pairs of orthogonal partial latin squares

abstract:
  We show that a pair of orthogonal partial latin squares of order $n$ can be
embedded in a pair of orthogonal latin squares of order at most $16n^4$ and all
orders greater than or equal to $48n^4$. This paper provides the first direct
polynomial order embedding construction in the literature.


title: Quaternionic contact Einstein manifolds

abstract:
  The main result is that the qc-scalar curvature of a seven dimensional
quaternionic contact Einstein manifold is a constant. In addition, we
characterize qc-Einstein structures with certain flat vertical connection and
develop their local structure equations. Finally, regular qc-Ricci flat
structures are shown to fibre over hyper-Kahler manifolds.


title: Direct observation of long-lived isomers in $^{212}$Bi

abstract:
  Long-lived isomers in 212Bi have been studied following 238U projectile
fragmentation at 670 MeV per nucleon. The fragmentation products were injected
as highly charged ions into the GSI storage ring, giving access to masses and
half-lives. While the excitation energy of the first isomer of 212Bi was
confirmed, the second isomer was observed at 1478(30) keV, in contrast to the
previously accepted value of >1910 keV. It was also found to have an extended
Lorentz-corrected in-ring halflife >30 min, compared to 7.0(3) min for the
neutral atom. Both the energy and half-life differences can be understood as
being due a substantial, though previously unrecognised, internal decay branch
for neutral atoms. Earlier shell-model calculations are now found to give good
agreement with the isomer excitation energy. Furthermore, these and new
calculations predict the existence of states at slightly higher energy that
could facilitate isomer de-excitation studies.


title: Asymmetric L\'evy flights in the presence of absorbing boundaries

abstract:
  We consider a one dimensional asymmetric random walk whose jumps are
identical, independent and drawn from a distribution \phi(\eta) displaying
asymmetric power law tails (i.e. \phi(\eta) \sim c/\eta^{\alpha +1} for large
positive jumps and \phi(\eta) \sim c/(\gamma |\eta|^{\alpha +1}) for large
negative jumps, with 0 < \alpha < 2). In absence of boundaries and after a
large number of steps n, the probability density function (PDF) of the walker
position, x_n, converges to an asymmetric L\'evy stable law of stability index
\alpha and skewness parameter \beta=(\gamma-1)/(\gamma+1). In particular the
right tail of this PDF decays as c n/x_n^{1+\alpha}. Much less is known when
the walker is confined, or partially confined, in a region of the space. In
this paper we first study the case of a walker constrained to move on the
positive semi-axis and absorbed once it changes sign. In this case, the
persistence exponent \theta_+, which characterizes the algebraic large time
decay of the survival probability, can be computed exactly and we show that the
tail of the PDF of the walker position decays as c \, n/[(1-\theta_+) \,
x_n^{1+\alpha}]. This last result can be generalized in higher dimensions such
as a planar L\'evy walker confined in a wedge with absorbing walls. Our results
are corroborated by precise numerical simulations.


title:
Proceedings of the 2013 UK National Conference on Geophysical,
  Astrophysical and Industrial Magnetohydrodynamics at Glasgow

abstract:
  This document presents an accurate record of the scientific programme of the
2013 UK National Conference on Geophysical, Astrophysical and Industrial
Magnetohydrodynamics held on 23rd and 24th of May 2013 at the School of
Mathematics and Statistics of the University of Glasgow. The abstracts of
presented contributions are listed in chronological order and a full list of
participants and their affiliations is included.

categories: physics.flu-dyn astro-ph.EP astro-ph.SR physics.plasm-ph


title: Unconventional TV Detection using Mobile Devices

abstract:
  Recent studies show that the TV viewing experience is changing giving the
rise of trends like "multi-screen viewing" and "connected viewers". These
trends describe TV viewers that use mobile devices (e.g. tablets and smart
phones) while watching TV. In this paper, we exploit the context information
available from the ubiquitous mobile devices to detect the presence of TVs and
track the media being viewed. Our approach leverages the array of sensors
available in modern mobile devices, e.g. cameras and microphones, to detect the
location of TV sets, their state (ON or OFF), and the channels they are
currently tuned to. We present the feasibility of the proposed sensing
technique using our implementation on Android phones with different realistic
scenarios. Our results show that in a controlled environment a detection
accuracy of 0.978 F-measure could be achieved.


title:
Nonrelativistic Limit of the Dirac-Schwarzschild Hamiltonian:
  Gravitational Zitterbewegung and Gravitational Spin-Orbit Coupling

abstract:
  We investigate the nonrelativistic limit of the gravitationally coupled Dirac
Equation via a Foldy-Wouthuysen transformation. The relativistic correction
terms have immediate and obvious physical interpretations in terms of a
gravitational zitterbewegung, and a gravitational spin-orbit coupling. We find
no direct coupling of the spin vector to the gravitational force, which would
otherwise violate parity. The particle-antiparticle symmetry described recently
by one of us in [Phys.Rev.A 87 (2013) 032101] is verified on the level of the
perturbative corrections accessed by the Foldy-Wouthuysen transformation. The
gravitational corrections to the electromagnetic transition current are
calculated.


title: Nonparametric Information Geometry

abstract:
  The differential-geometric structure of the set of positive densities on a
given measure space has raised the interest of many mathematicians after the
discovery by C.R. Rao of the geometric meaning of the Fisher information. Most
of the research is focused on parametric statistical models. In series of
papers by author and coworkers a particular version of the nonparametric case
has been discussed. It consists of a minimalistic structure modeled according
the theory of exponential families: given a reference density other densities
are represented by the centered log likelihood which is an element of an Orlicz
space. This mappings give a system of charts of a Banach manifold. It has been
observed that, while the construction is natural, the practical applicability
is limited by the technical difficulty to deal with such a class of Banach
spaces. It has been suggested recently to replace the exponential function with
other functions with similar behavior but polynomial growth at infinity in
order to obtain more tractable Banach spaces, e.g. Hilbert spaces. We give
first a review of our theory with special emphasis on the specific issues of
the infinite dimensional setting. In a second part we discuss two specific
topics, differential equations and the metric connection. The position of this
line of research with respect to other approaches is briefly discussed.


title:
Run-and-tumble in a crowded environment: persistent exclusion process
  for swimmers

abstract:
  The effect of crowding on the run-and-tumble dynamics of swimmers such as
bacteria is studied using a discrete lattice model of mutually excluding
particles that move with constant velocity along a direction that is randomized
at a rate $\alpha$. In stationary state, the system is found to break into
dense clusters in which particles are trapped or stopped from moving. The
characteristic size of these clusters predominantly scales as $\alpha^{-0.5}$
both in 1D and 2D. For a range of densities, due to cooperative effects, the
stopping time scales as ${\cal T}_{1d}^{0.85}$ and as ${\cal T}_{2d}^{0.8}$,
where ${\cal T}_d$ is the diffusive time associated with the motion of cluster
boundaries. Our findings might be helpful in understanding the early stages of
biofilm formation.


title:
Incorporating gravity into trace dynamics: the induced gravitational
  action

abstract:
  We study the incorporation of gravity into the trace dynamics framework for
classical matrix-valued fields, from which we have proposed that quantum field
theory is the emergent thermodynamics, with state vector reduction arising from
fluctuation corrections to this thermodynamics. We show that the metric must be
incorporated as a classical, not a matrix-valued, field, with the source for
gravity the exactly covariantly conserved trace stress-energy tensor of the
matter fields. We then study corrections to the classical gravitational action
induced by the dynamics of the matrix-valued matter fields, by examining the
average over the trace dynamics canonical ensemble of the matter field action,
in the presence of a general background metric. Using constraints from global
Weyl scaling and three-space general coordinate transformations, we show that
to zeroth order in derivatives of the metric, the induced gravitational action
in the preferred rest frame of the trace dynamics canonical ensemble must have
the form $$ \Delta S=\int d^4x (^{(4)}g)^{1/2}(g_{00})^{-2} A\big(g_{0i} g_{0j}
g^{ij}/g_{00}, D^ig_{ij}D^j/g_{00}, g_{0i}D^i/g_{00}\big), $$ with $D^i$
defined through the co-factor expansion of $^{(4)}g$ by
$^{(4)}g/{^{(3)}g}=g_{00}+g_{0i}D^i$, and with $A(x,y,z)$ a general function of
its three arguments. This action has "chameleon-like" properties: For the
Robertson-Walker cosmological metric, it {\it exactly} reduces to a
cosmological constant, but for the Schwarzschild metric it diverges as
$(1-2M/r)^{-2}$ near the Schwarzschild radius, indicating that it will
substantially affect the horizon structure.

categories: gr-qc astro-ph.CO hep-th math-ph math.MP quant-ph


title:
Strong anisotropic influence of local-field effects on the dielectric
  response of {\alpha}-MoO3

abstract:
  Dielectric properties of {\alpha}-MoO3 are investigated by a combination of
valence electron-energy loss spectroscopy and ab initio calculation at the
random phase approximation level with the inclusion of local-field effects
(LFE). A meticulous comparison between experimental and calculated spectra is
performed in order to interpret calculated dielectric properties. The
dielectric function of MoO3 has been obtained along the three axes and the
importance of LFE has been shown. In particular, taking into account LFE is
shown to be essential to describe properly the intensity and position of the
Mo-N2,3 edges as well as the low energy part of the spectrum. A detailed study
of the energy-loss function in connection with the dielectric response function
also shows that the strong anisotropy of the energy-loss function of
{\alpha}-MoO3 is driven by an anisotropic influence of LFE. These LFE
significantly dampen a large peak in {\epsilon}2, but only along the [010]
direction. Thanks to a detailed analysis at specific k-points of the orbitals
involved in this transition, the origin of this peak has not only been
evidenced but a connection between the inhomogeneity of the electron density
and the anisotropic influence of local-field effects has also been established.
More specifically, this anisotropy is governed by a strongly inhomogeneous
spatial distribution of the empty states. This depletion of the empty states is
localized around the terminal oxygens and accentuates the electron
inhomogeneity.


title:
IGR J17354-3255 as bench test for investigation of gamma-ray emission
  from Supergiant Fast X-ray Transients

abstract:
  Among the different types of sources shining in the high energy sky,
gamma-ray binaries are rapidly becoming the subject of major interest. In fact,
in the last few years a number of High Mass X-ray Binaries (HMXBs) have been
firmly detected from MeV to TeV energies, providing secure evidences that
particles can be efficiently accelerated up to very high energies in such
galactic systems. Similarly to this general and emerging class of gamma-ray
binaries, in principle Supergiant Fast X-ray Transients (SFXTs) have all the
"ingredients" to be transient high energy emitters. In this context, the SFXT
IGR J17354-3255 is a good bench test and we present intriguing hints likely
suggesting that it is a transient gamma-ray source flaring on short timescales.
If fully confirmed by further studies, the implications stemming are huge, both
theoretically and observationally, and would add a further extreme
characteristic to the already extreme class of SFXTs.


title: Multiparameter Weyl Algebras

abstract:
  We introduce a family of unital associative algebras A which are
multiparameter analogues of the Weyl algebras and determine the simple weight
modules and the Whittaker modules for them. All these modules can be regarded
as spaces of (Laurent) polynomials with certain A-actions on them.
  This paper was written in February 2008 and some copies of it were
distributed, but it has never been posted or published. We thank Bryan Bischof
and Jason Gaddis for their interest in the work and for encouraging us to make
the paper more widely available. The references in this posted version have
been updated, and some cosmetic changes made; in particular, some typos have
been corrected. The investigations have been generalized by V. Futorny and J.
Hartwig to the context of multiparameter twisted Weyl algebras (see Journal of
Algebra 357 (2012), 69-93).


title:
Analytical Solutions of the Dirac and the Klein-Gordon Equations in
  Plasma Induced by High Intensity Laser

abstract:
  In this paper we obtain analytical solutions of the Dirac and the
Klein-Gordon equations coupled to a strong electromagnetic wave in the presence
of plasma environment. These are a generalization of the familiar Volkov
solutions. The contribution of the non-zero photon effective mass to the scalar
and fermion wavefunctions, conserved quantities and effective mass is
demonstrated for the first time. The new wavefunctions exhibit differences from
Volkov solutions for nowadays available laser intensity.


title:
Exact solution for quantum spin-1/2 Ising-Heisenberg orthogonal-dimer
  chain with the Heisenberg intra-dimer and Ising inter-dimer interactions

abstract:
  The quantum spin-1/2 orthogonal-dimer chain with the Heisenberg intra-dimer
and Ising inter-dimer interactions in a magnetic field is considered by a
rigorous approach. The model conserves the z-component of total spin on
vertical Heisenberg bonds and this property is used to calculate exactly the
partition function using the transfer-matrix method. We have found the
ground-state phase diagram of the given model in a magnetic field as well as
the macroscopic degeneracy along field-induced transitions accompanied with the
magnetization jumps. The model exhibits two intermediate fractional plateaux at
one-quarter and one-half of the saturation magnetization. We have examined the
effect of the exchange anisotropy in the XXZ Heisenberg intra-dimer interaction
on the ground state. It is shown that the one-quarter and one-half plateaux may
disappear from the magnetization curve for the ferromagnetic Heisenberg
intra-dimer interaction. We have also rigorously studied the effect of
frustrated interactions on the thermodynamic and magnetic properties of the
model and show how the macroscopic degeneracy of the ground state is reflected
in the low-temperature behavior of the magnetization, entropy and specific
heat. A possibility of observing enhanced magnetocaloric effect during the
adiabatic demagnetization is discussed in detail.


title: Cavitation in dielectric fluid in inhomogeneous pulsed electric field

abstract:
  This paper proposes a method for studying the early stages of the cavitation
development in arbitrary, non-stationary conditions. This method is based on
the comparison of the results of calculations in the framework of a theoretical
model of the liquid dielectrics motion in a strong non-uniform electric field
and experiments with controlled parameters. This approach allows us to find the
critical negative pressure, at which cavitation begins to develop, and to
determine the values of the constants in the classical models of cavitation.


title:
TraMoS project III: Improved physical parameters, timing analysis, and
  star-spot modelling of the WASP-4b exoplanet system from 38 transit
  observations

abstract:
  We report twelve new transit observations of the exoplanet WASP-4b from the
Transit Monitoring in the South Project (TraMoS) project. These transits are
combined with all previously published transit data for this planet to provide
an improved radius measurement of Rp = 1.395 +- 0.022 Rjup and improved transit
ephemerides. In a new homogeneous analysis in search for Transit Timing
Variations (TTVs) we find no evidence of those with RMS amplitudes larger than
20 seconds over a 4-year time span. This lack of TTVs rules out the presence of
additional planets in the system with masses larger than about 2.5 M_earth, 2.0
M_earth, and 1.0 M_earth around the 1:2, 5:3 and 2:1 orbital resonances. Our
search for the variation of other parameters, such as orbital inclination and
transit depth also yields negative results over the total time span of the
transit observations. Finally we perform a simple study of stellar spots
configurations of the system and conclude that the star rotational period is
about 34 days.