title:
Modular perverse sheaves on flag varieties II: Koszul duality and
  formality

abstract:
  Building on the theory of parity sheaves due to Juteau-Mautner-Williamson, we
develop a formalism of "mixed modular perverse sheaves" for varieties equipped
with a stratification by affine spaces. We then give two applications: (1) a
"Koszul-type" derived equivalence relating a given flag variety to the
Langlands dual flag variety, and (2) a formality theorem for the modular
derived category of a flag variety (extending a previous result of
Riche-Soergel-Williamson).


title:
Isotropic vortex tangles in trapped atomic Bose-Einstein condensates via
  laser stirring

abstract:
  The generation of isotropic vortex configurations in trapped atomic
Bose-Einstein condensates offers a platform to elucidate quantum turbulence on
mesoscopic scales. We demonstrate that a laser-induced obstacle moving in a
figure-eight path within the condensate provides a simple and effective means
to generate an isotropic three-dimensional vortex tangle due to its minimal net
transfer of angular momentum to the condensate. Our characterisation of vortex
structures and their isotropy is based on projected vortex lengths and velocity
statistics obtained numerically via the Gross-Pitaevskii equation. Our
methodology provides a possible experimental route for generating and
characterising vortex tangles and quantum turbulence in atomic Bose-Einstein
condensates.


title: Antimatter in the Universe : Constraints from Gamma-Ray Astronomy

abstract:
  We review gamma-ray observations that constrain antimatter - both baryonic
and leptonic - in the Universe. Antimatter can be probed through ordinary
matter, with the resulting annihilation gamma-rays providing indirect evidence
for its presence. Although it is generally accepted that equal amounts of
matter and antimatter have been produced in the Big Bang, gamma-rays have so
far failed to detect substantial amounts of baryonic antimatter in the
Universe. Conversely, positrons are abundantly observed through their
annihilation in the central regions of our Galaxy and, although a wealth of
astrophysical sources are plausible, their very origin is still unknown. As
both antimatter questions - the source of the Galactic positrons and the baryon
asymmetry in the Universe - can be investigated through the low energy
gamma-ray channel, the mission concept of a dedicated space telescope is
sketched out.


title: Uniqueness of reduced alternating rational 3-tangles

abstract:
  In this paper, We introduce an invariant of rational n-tangles which is
obtained from the Kauffman bracket. It forms a vector with Laurent polynomial
entries. We prove that the invariant classifies the rational 2-tangles and the
reduced alternating rational 3-tangles. We conjecture that it classifies the
rational 3-tangles as well.


title:
Coherent versus incoherent excitation dynamics in dissipative many-body
  Rydberg systems

abstract:
  We study the impact of dephasing on the excitation dynamics of a cloud of
ultracold two-level Rydberg atoms for both resonant and off-resonant laser
excitation, using the wave function Monte Carlo (MCWF) technique. We find that
while for resonant laser driving, dephasing mainly leads to an increase of the
Rydberg population and a decrease of the Mandel Q parameter, at off-resonant
driving strong dephasing toggles between direct excitation of pairs of atoms
and subsequent excitation of single atoms, respectively. These two excitation
mechanisms can be directly quantified via the pair correlation function, which
shows strong suppression of the two-photon resonance peak for strong dephasing.
Consequently, qualitatively different dynamics arise in the excitation
statistics for weak and strong dephasing in off-resonant excitation. Our
findings show that time-resolved excitation number measurements can serve as a
powerful tool to identify the dominating process in the system's excitation
dynamics.


title: On the Cooperative Communication over Cognitive Interference Channel

abstract:
  In this paper, we investigate the problem of communication over cognitive
interference channel (CIC) with partially cooperating (PC) destinations
(CIC-PC). This channel consists of two source nodes communicating two
independent messages to their corresponding destination nodes. One of the
sources, referred to as the cognitive source, has a noncausal knowledge of the
message of the other source, referred to as the primary source. Each
destination is assumed to decode only its intended message. In addition, the
destination corresponding to the cognitive source assists the other destination
by transmitting cooperative information through a relay link. We derive a new
upper bound on the capacity region of discrete memoryless CI-CPC. Moreover, we
characterize the capacity region for two new classes of this channel: (1)
degraded CIC-PC, and (2) a class of semideterministic CIC-PC.


title:
Impact of Spectrum Sharing on the Efficiency of Faster-Than-Nyquist
  Signaling

abstract:
  Capacity computations are presented for Faster-Than-Nyquist (FTN) signaling
in the presence of interference from neighboring frequency bands. It is shown
that Shannon's sinc pulses maximize the spectral efficiency for a multi-access
channel, where spectral efficiency is defined as the sum rate in bits per
second per Hertz. Comparisons using root raised cosine pulses show that the
spectral efficiency decreases monotonically with the roll-off factor. At high
signal-to-noise ratio, these pulses have an additive gap to capacity that
increases monotonically with the roll-off factor.


title: Superconcentration on a Pair of Butterflies

abstract:
  Suppose we concatenate two directed graphs, each isomorphic to a $d$
dimensional butterfly (but not necessarily identical to each other). Select any
set of $2^k$ input and $2^k$ output nodes on the resulting graph. Then there
exist node disjoint paths from the input nodes to the output nodes. If we take
two standard butterflies and permute the order of the layers, then the result
holds on sets of any size, not just powers of two.


title: Convergence bound in total variation for an image restoration model

abstract:
  We consider a stochastic image restoration model proposed by A. Gibbs (2004),
and give an upper bound on the time it takes for a Markov chain defined by this
model to be \epsilon - close in total variation to equilibrium. We use Gibbs'
result for convergence in the Wasserstein metric to arrive at our result. Our
bound for the time to equilibrium of similar order to that of Gibbs.


title: Multiplicative quadratic maps

abstract:
  In this paper we prove that a multiplicative quadratic map between a unital
ring $K$ and a field $L$ is induced by a homomorphism from $K$ into $L$ or a
composition algebra over $L$. Especially we show that if $K$ is a field, then
every multiplicative quadratic map is the product of two field homomorphisms.
Moreover, we prove a multiplicative version of Artin's Theorem showing that a
product of field homomorphisms is unique up to multiplicity.


title:
Remarks on the derivation and evaluation of the Stacey-Sigmar model for
  tokamak equilibrium

abstract:
  The Stacey-Sigmar model for tokamak equilibrium as presented in the
literature relies heavily on the neoclassical theory of the electrostatic
field. Its neglect of Gauss's law is inconsistent with the potential
formulation of electrodynamics. Its treatment of the dynamic electric field
generated by the central heating and poloidal field coils also is suspect. Its
derivation of the viscosity term remains incomplete and does not account for
the varying pitch angle of the magnetic field. A derivation of the viscosity
term which respects the pitch angle can account for the radial force commonly
ascribed to the radial electrostatic field, thereby obviating the desire to
neglect Gauss's law.


title: Community Detection in Networks with Node Attributes

abstract:
  Community detection algorithms are fundamental tools that allow us to uncover
organizational principles in networks. When detecting communities, there are
two possible sources of information one can use: the network structure, and the
features and attributes of nodes. Even though communities form around nodes
that have common edges and common attributes, typically, algorithms have only
focused on one of these two data modalities: community detection algorithms
traditionally focus only on the network structure, while clustering algorithms
mostly consider only node attributes. In this paper, we develop Communities
from Edge Structure and Node Attributes (CESNA), an accurate and scalable
algorithm for detecting overlapping communities in networks with node
attributes. CESNA statistically models the interaction between the network
structure and the node attributes, which leads to more accurate community
detection as well as improved robustness in the presence of noise in the
network structure. CESNA has a linear runtime in the network size and is able
to process networks an order of magnitude larger than comparable approaches.
Last, CESNA also helps with the interpretation of detected communities by
finding relevant node attributes for each community.


title:
Enhancement of Electronic Spin Susceptibility in Pauli Limited
  Unconventional Superconductors

abstract:
  We calculate the wave-vector dependent electronic spin susceptibility
$\chi_{\alpha\beta}(\mathbf q, \mathbf H_0)$ of a d-wave superconductor in
uniform magnetic field $\mathbf{H}_0$ with Pauli pair-breaking. We find that
the transverse component of the susceptibility tensor can be greater than its
normal state value; the longitudinal component also slightly increases but in a
very limited range of $q$s. We identify several wave vectors $\{\mathbf
q_\perp,\mathbf q_\parallel\}$, that correspond to the maxima of either
$\chi_\perp$ or $\chi_\parallel$. We compare our results with available data on
the high-field phase in heavy-fermion CeCoIn$_5$.


title: Glass-Transition Properties from Hard Spheres to Charged Point Particles

abstract:
  The glass transition is investigated in three dimensions for single and
double Yukawa potentials for the full range of control parameters. For
vanishing screening parameter, the limit of the one-component plasma is
obtained; for large screening parameters and high coupling strengths, the
glass-transition properties crossover to the hard-sphere system. Between the
two limits, the entire transition diagram can be described by analytical
functions. Different from other potentials, the glass-transition and melting
lines for Yukawa potentials are found to follow shifted but otherwise identical
curves in control-parameter space.


title: The Higgs System in and Beyond the Standard Model

abstract:
  After the discovery of the Higgs boson particle on the 4th of July of 2012 at
the Large Hadron Collider, sited at the european CERN laboratory, we are
entering in a fascinating period for Particle Physics where both theorists and
experimentalists are devoted to fully understand the features of this new
particle and the possible consequences for High Energy Physics of the Higgs
system both within and beyond the Standard Model of fundamental particle
interactions. This paper is a summary of the lectures given at the third IDPASC
school (Santiago de Compostela, Feb. 2013, Spain) addressed to PhD students,
and contains a short introduction to the main basic aspects of the Higgs boson
particle in and beyond the Standard Model.


title: Multi-Mode Oscillations in Classical Cepheids and RR Lyrae-Type Stars

abstract:
  I review different types of multi-mode pulsations observed in classical
Cepheids and in RR Lyrae-type star. The presentation concentrates on the newest
results, with special emphasis on recently detected nonradial oscillations.


title: Consequences of Kondo exchange on quantum spins

abstract:
  When individual quantum spins are placed in close proximity to conducting
substrates, the localized spin is coupled to the nearby itinerant conduction
electrons via Kondo exchange. In the strong coupling limit this can result in
the Kondo effect - the formation of a correlated, many body singlet state - and
a resulting renormalization of the density of states near the Fermi energy.
However, even when Kondo screening does not occur, Kondo exchange can give rise
to a wide variety of other phenomena. In addition to the well known
renormalization of the g factor and the finite spin decoherence and relaxation
times, Kondo exchange has recently been found to give rise to a newly
discovered effect: the renormalization of the single ion magnetic anisotropy.
Here we put these apparently different phenomena on equal footing by treating
the effect of Kondo exchange perturbatively. In this formalism, the central
quantity is $\rho J$, the product of the density of states at the Fermi energy
$\rho$ and the Kondo exchange constant J. We show that perturbation theory
correctly describes the experimentally observed exchange induced shifts of the
single spin excitation energies, demonstrating that Kondo exchange can be used
to tune the effective magnetic anisotropy of a single spin.


title: On Stochastic Estimation of Partition Function

abstract:
  In this paper, we show analytically that the duality of normal factor graphs
(NFG) can facilitate stochastic estimation of partition functions. In
particular, our analysis suggests that for the $q-$ary two-dimensional
nearest-neighbor Potts model, sampling from the primal NFG of the model and
sampling from its dual exhibit opposite behaviours with respect to the
temperature of the model. For high-temperature models, sampling from the primal
NFG gives rise to better estimators whereas for low-temperature models,
sampling from the dual gives rise to better estimators. This analysis is
validated by experiments.


title:
On Yangian-invariant regularisation of deformed on-shell diagrams in N=4
  super-Yang-Mills theory

abstract:
  We investigate Yangian invariance of deformed on-shell diagrams with D=4, N=4
superconformal symmetry. We find that invariance implies a direct relationship
between the deformation parameters and the permutation associated to the
on-shell graph. We analyse the connection with deformations of scattering
amplitudes in N=4 super-Yang-Mills theory and the possibility of using the
deformation parameters as a regulator preserving Yangian invariance. A study of
higher-point tree and loop graphs suggests that manifest Yangian invariance of
the amplitude requires trivial deformation parameters.


title:
Kepler-413b: a slightly misaligned, Neptune-size transiting circumbinary
  planet

abstract:
  We report the discovery of a transiting, Rp = 4.347+/-0.099REarth,
circumbinary planet (CBP) orbiting the Kepler K+M Eclipsing Binary (EB) system
KIC 12351927 (Kepler-413) every ~66 days on an eccentric orbit with ap =
0.355+/-0.002AU, ep = 0.118+/-0.002. The two stars, with MA =
0.820+/-0.015MSun, RA = 0.776+/-0.009RSun and MB = 0.542+/-0.008MSun, RB =
0.484+/-0.024RSun respectively revolve around each other every
10.11615+/-0.00001 days on a nearly circular (eEB = 0.037+/-0.002) orbit. The
orbital plane of the EB is slightly inclined to the line of sight (iEB =
87.33+/-0.06 degrees) while that of the planet is inclined by ~2.5 degrees to
the binary plane at the reference epoch. Orbital precession with a period of
~11 years causes the inclination of the latter to the sky plane to continuously
change. As a result, the planet often fails to transit the primary star at
inferior conjunction, causing stretches of hundreds of days with no transits
(corresponding to multiple planetary orbital periods). We predict that the next
transit will not occur until 2020. The orbital configuration of the system
places the planet slightly closer to its host stars than the inner edge of the
extended habitable zone. Additionally, the orbital configuration of the system
is such that the CBP may experience Cassini-States dynamics under the influence
of the EB, in which the planet's obliquity precesses with a rate comparable to
its orbital precession. Depending on the angular precession frequency of the
CBP, it could potentially undergo obliquity fluctuations of dozens of degrees
(and complex seasonal cycles) on precession timescales.


title:
Comment on: Comment on "Mysterious abrupt carbon-14 increase in coral
  contributed by a comet" Yi Liu et al

abstract:
  Unfortunately, Liu et al. contains a number of errors and omissions which
compromise its conclusions. These have to do with the amount of 14C which is
necessary to deposit in the atmosphere in order to see a perturbation like that
in 774 AD, and the ability of a comet to do so.

categories: astro-ph.EP astro-ph.HE astro-ph.SR physics.ao-ph physics.geo-ph


title:
Compact two-electron wave function for bond dissociation and Van der
  Waals interactions: A natural amplitude assessment

abstract:
  Electron correlations in molecules can be divided in short range dynamical
correlations, long range Van der Waals type interactions and near degeneracy
static correlations. In this work we analyze for a one-dimensional model of a
two-electron system how these three types of correlations can be incorporated
in a simple wave function of restricted functional form consisting of an
orbital product multiplied by a single correlation function $f(r_{12})$
depending on the interelectronic distance $r_{12}$. Since the three types of
correlations mentioned lead to different signatures in terms of the natural
orbital (NO) amplitudes in two-electron systems we make an analysis of the wave
function in terms of the NO amplitudes for a model system of a diatomic
molecule. In our numerical implementation we fully optimize the orbitals and
the correlation function on a spatial grid without restrictions on their
functional form. Due to this particular form of the wave function, we can prove
that none of the amplitudes vanishes and moreover that it displays a distinct
sign pattern and a series of avoided crossings as a function of the bond
distance in agreement with the exact solution. This shows that the wave
function Ansatz correctly incorporates the long range Van der Waals
interactions. We further show that the approximate wave function gives an
excellent binding curve and is able to describe static correlations. We show
that in order to do this the correlation function $f(r_{12})$ needs to diverge
for large $r_{12}$ at large internuclear distances while for shorter bond
distances it increases as a function of $r_{12}$ to a maximum value after which
it decays exponentially. We further give a physical interpretation of this
behavior.

categories: physics.chem-ph cond-mat.str-el physics.atom-ph physics.comp-ph quant-ph


title: Minimax-optimal nonparametric regression in high dimensions

abstract:
  Minimax $L_2$ risks for high-dimensional nonparametric regression are derived
under two sparsity assumptions: (1) the true regression surface is a sparse
function that depends only on $d=O(\log n)$ important predictors among a list
of $p$ predictors, with $\log p=o(n)$; (2) the true regression surface depends
on $O(n)$ predictors but is an additive function where each additive component
is sparse but may contain two or more interacting predictors and may have a
smoothness level different from other components. For either modeling
assumption, a practicable extension of the widely used Bayesian Gaussian
process regression method is shown to adaptively attain the optimal minimax
rate (up to $\log n$ terms) asymptotically as both $n,p\to\infty$ with $\log
p=o(n)$.


title: Optimal control and numerical software: an overview

abstract:
  Optimal Control (OC) is the process of determining control and state
trajectories for a dynamic system, over a period of time, in order to optimize
a given performance index. With the increasing of variables and complexity, OC
problems can no longer be solved analytically and, consequently, numerical
methods are required. For this purpose, direct and indirect methods are used.
Direct methods consist in the discretization of the OC problem, reducing it to
a nonlinear constrained optimization problem. Indirect methods are based on the
Pontryagin Maximum Principle, which in turn reduces to a boundary value
problem. In order to have a more reliable solution, one can solve the same
problem through different approaches. Here, as an illustrative example, an
epidemiological application related to the rubella disease is solved using
several software packages, such as the routine ode45 of Matlab, OC-ODE, DOTcvp
toolbox, IPOPT and Snopt, showing the state of the art of numerical software
for OC.


title:
Localisation in space and time in disordered-lattice open quantum
  dynamics

abstract:
  We study a two-dimensional tight-binding lattice for excitons with on-site
disorder, coupled to a thermal environment at infinite temperature. The
disorder acts to localise an exciton spatially, while the environment generates
dynamics which enable exploration of the lattice. Although the steady state of
the system is trivially uniform, we observe a rich dynamics and uncover a
dynamical phase transition in the space of temporal trajectories. This
transition is identified as a localisation in the dynamics generated by the
bath. We explore spatial features in the dynamics and employ a generalisation
of the inverse participation ratio to deduce an ergodic timescale for the
lattice.


title: Conformal Inflation Coupled to Matter

abstract:
  We formulate new conformal models of inflation and dark energy which
generalise the Higgs-Dilaton scenario. We embed these models in unimodular
gravity whose effect is to break scale invariance in the late time Universe. In
the early Universe, inflation occurs close to a maximum of both the scalar
potential and the scalar coupling to the Ricci scalar in the Jordan frame. At
late times, the dilaton, which decouples from the dynamics during inflation,
receives a potential term from unimodular gravity and leads to the acceleration
of the Universe. We address two central issues in this scenario. First we show
that the Damour-Polyalov mechanism, when non-relativistic matter is present
prior to the start of inflation, sets the initial conditions for inflation at
the maximum of the scalar potential. We then show that conformal invariance
implies that matter particles are not coupled to the dilaton in the late
Universe at the classical level. When fermions acquire masses at low energy,
scale invariance is broken and quantum corrections induce a coupling between
the dilaton and matter which is still small enough to evade the gravitational
constraints in the solar system.


title: A Unified Theory of Chemical Reactions

abstract:
  We propose a new and general formalism for elementary chemical reactions
where quantum electronic variables are used as reaction coordinates. This
formalism is in principle applicable to all kinds of chemical reactions ionic
or covalent. Our theory reveals the existence of an intermediate situation
between ionic and covalent which may be almost barrierless and isoenegetic and
which should be of high interest for understanding biochemistry.


title: GRB 131231A: Implications of the GeV emission

abstract:
  GRB 131231A was detected by the Large Area Telescope onboard Fermi Space
Gamma-ray Telescope. The high energy gamma-ray ($> 100$ MeV) afterglow emission
spectrum is $F_\nu \propto \nu^{-0.54\pm0.15}$ in the first $\sim 1300$ s after
the trigger and the most energetic photon has an energy $\sim 62$ GeV arriving
at $t\sim 520$ s. With reasonable parameters of the GRB outflow as well as the
density of the circum-burst medium, the synchrotron radiation of electrons or
protons accelerated at an external forward shock have difficulty accounting for
the data. The synchrotron self-Compton radiation of the forward
shock-accelerated electrons, instead, can account for both the spectrum and
temporal behavior of the GeV afterglow emission. We also show that the prospect
for detecting GRB 131231A$-$like GRBs with Cherenkov Telescope Array (CTA) is
promising.


title: Minimizing Flow-Time on Unrelated Machines

abstract:
  We consider some flow-time minimization problems in the unrelated machines
setting. In this setting, there is a set of $m$ machines and a set of $n$ jobs,
and each job $j$ has a machine dependent processing time of $p_{ij}$ on machine
$i$. The flow-time of a job is the total time the job spends in the system
(completion time minus its arrival time), and is one of the most natural
quality of service measure. We show the following two results: an
$O(\min(\log^2 n,\log n \log P))$ approximation algorithm for minimizing the
total-flow time, and an $O(\log n)$ approximation for minimizing the maximum
flow-time. Here $P$ is the ratio of maximum to minimum job size. These are the
first known poly-logarithmic guarantees for both the problems.


title:
Comparing commutative and associative unbounded differential graded
  algebras over Q from homotopical point of view

abstract:
  In this paper we establish a faithfulness result, in a homotopical sense,
between a subcategory of the model category of augmented differential graded
commutative algebras CDGA and a subcategory of the model category of augmented
differential graded algebras DGA over the field of rational numbers
$\mathbb{Q}$.


title:
The Ultraviolet View of the Magellanic Clouds from GALEX: A First Look
  at the LMC Source Catalog

abstract:
  The Galaxy Evolution Exporer (GALEX) has performed unprecedented imaging
surveys of the Magellanic Clouds (MC) and their surrounding areas including the
Magellanic Bridge (MB) in near-UV (NUV, 1771-2831\AA) and far-UV (FUV,
1344-1786\AA) bands at 5" resolution. Substantially more area was covered in
the NUV than FUV, particularly in the bright central regions, because of the
GALEX FUV detector failure. The 5$\sigma$ depth of the NUV imaging varies
between 20.8 and 22.7 (ABmag). Such imaging provides the first sensitive view
of the entire content of hot stars in the Magellanic System, revealing the
presence of young populations even in sites with extremely low star-formation
rate surface density like the MB, owing to high sensitivity of the UV data to
hot stars and the dark sky at these wavelengths.
  The density of UV sources is quite high in many areas of the LMC and SMC.
Crowding limits the quality of source detection and photometry from the
standard mission pipeline processing. We performed custom-photometry of the
GALEX data in the MC survey region ($<15^{\circ}$ from the LMC, $<10^{\circ}$
from the SMC). After merging multiple detections of sources in overlapping
images, the resulting catalog we have produced for the LMC contains nearly 6
million unique NUV point sources within 15$^{\circ}$ and is briefly presented
herein. This paper provides a first look at the GALEX MC survey and highlights
some of the science investigations that the entire catalog and imaging dataset
will make possible.


title:
Learning dynamics explains human behavior in Prisoner's Dilemma on
  networks

abstract:
  Cooperative behavior lies at the very basis of human societies, yet its
evolutionary origin remains a key unsolved puzzle. Whereas reciprocity or
conditional cooperation is one of the most prominent mechanisms proposed to
explain the emergence of cooperation in social dilemmas, recent experimental
findings on networked Prisoner's Dilemma games suggest that conditional
cooperation also depends on the previous action of the player---namely on the
`mood' in which the player currently is. Roughly, a majority of people behaves
as conditional cooperators if they cooperated in the past, while they ignore
the context and free-ride with high probability if they did not. However, the
ultimate origin of this behavior represents a conundrum itself. Here we aim
specifically at providing an evolutionary explanation of moody conditional
cooperation. To this end, we perform an extensive analysis of different
evolutionary dynamics for players' behavioral traits---ranging from standard
processes used in game theory based on payoff comparison to others that include
non-economic or social factors. Our results show that only a dynamic built upon
reinforcement learning is able to give rise to evolutionarily stable moody
conditional cooperation, and at the end to reproduce the human behaviors
observed in the experiments.


title:
Spatially-Coupled Precoded Rateless Codes with Bounded Degree Achieve
  the Capacity of BEC under BP decoding

abstract:
  Raptor codes are known as precoded rateless codes that achieve the capacity
of BEC. However the maximum degree of Raptor codes needs to be unbounded to
achieve the capacity. In this paper, we prove that spatially-coupled precoded
rateless codes achieve the capacity with bounded degree under BP decoding.


title:
Spatially-Coupled MacKay-Neal Codes with No Bit Nodes of Degree Two
  Achieve the Capacity of BEC

abstract:
  Obata et al. proved that spatially-coupled (SC) MacKay-Neal (MN) codes
achieve the capacity of BEC. However, the SC-MN codes codes have many variable
nodes of degree two and have higher error floors. In this paper, we prove that
SC-MN codes with no variable nodes of degree two achieve the capacity of BEC.


title: Non-Binary LDPC Codes with Large Alphabet Size

abstract:
  We study LDPC codes for the channel with input ${x}\in \mathbb{F}_q^m$ and
output ${y}={x}+{z}\in \mathbb{F}_q^m$. The aim of this paper is to evaluate
decoding performance of $q^m$-ary non-binary LDPC codes for large $m$. We give
density evolution and decoding performance evaluation for regular non-binary
LDPC codes and spatially-coupled (SC) codes. We show the regular codes do not
achieve the capacity of the channel while SC codes do.


title: The Generalized Fractional Calculus of Variations

abstract:
  We review the recent generalized fractional calculus of variations. We
consider variational problems containing generalized fractional integrals and
derivatives and study them using indirect methods. In particular, we provide
necessary optimality conditions of Euler-Lagrange type for the fundamental and
isoperimetric problems, natural boundary conditions, and Noether type theorems.


title: Absorbing sets and Baker domains for holomorphic maps

abstract:
  We consider holomorphic maps $f: U \to U$ for a hyperbolic domain $U$ in the
complex plane, such that the iterates of $f$ converge to a boundary point
$\zeta$ of $U$. By a previous result of the authors, for such maps there exist
nice absorbing domains $W \subset U$. In this paper we show that $W$ can be
chosen to be simply connected, if $f$ has parabolic I type in the sense of the
Baker--Pommerenke--Cowen classification of its lift by a universal covering
(and $\zeta$ is not an isolated boundary point of $U$). Moreover, we provide
counterexamples for other types of the map $f$ and give an exact
characterization of parabolic I type in terms of the dynamical behaviour of
$f$.


title: Polar coding for interference networks

abstract:
  A polar coding scheme for interference networks is introduced. The scheme
combines Arikan's monotone chain rules for multiple-access channels and a
method by Hassani and Urbanke to 'align' two incompatible polarization
processes. It achieves the Han--Kobayashi inner bound for two-user interference
channels and generalizes to interference networks.


title:
Adaptive gradient-augmented level set method with multiresolution error
  estimation

abstract:
  A space-time adaptive scheme is presented for solving advection equations in
two space dimensions. The gradient-augmented level set method using a
semi-Lagrangian formulation with backward time integration is coupled with a
point value multiresolution analysis using Hermite interpolation. Thus locally
refined dyadic spatial grids are introduced which are efficiently implemented
with dynamic quadtree data structures. For adaptive time integration, an
embedded Runge-Kutta method is employed. The precision of the new fully
adaptive method is analysed and speed up of CPU time and memory compression
with respect to the uniform grid discretization are reported.


title:
Rigidity Conditions for the Boundaries of Submanifolds in a Riemannian
  Manifold

abstract:
  Developing A.D. Aleksandrov's ideas, the first-named author of this article
proposed the following approach to study of rigidity problems for the boundary
of a $C^0$-submanifold in a smooth Riemannian manifold: Let $Y_1$ be a
2-dimensional compact connected $C^0$-submanifold with nonempty boundary in a
2-dimensional smooth connected Riemannian manifold $(X,g)$ without boundary
satisfying the condition $$\rho_{Y_1}(x,y) = \liminf_{x' \to x, y' \to y, x',y'
\in \mathop{\rm Int} Y_1} \{[l(\gamma_{x',y',\mathop{\rm Int} Y_1})]\} <
\infty,$$ if $x,y \in Y_1$. Here $\inf[l(\gamma_{x',y',\mathop{\rm Int} Y_1})]$
is the infimum of the length of smooth paths joining $x'$ and $y'$ in the
interior $\mathop{\rm Int} Y_1$ of $Y_1$. In the present paper, we first
establish that $\rho_{Y_1}$ is a metric on $Y_1$. Suppose further that $Y_1$ is
strictly convex in the metric $\rho_{Y_1}$. Consider another 2-dimensional
compact connected $C^0$-submanifold $Y_2$ of $X$ with boundary satisfying the
condition $\rho_{Y_2}(x,y) < \infty$, $x,y \in Y_2$, and assume that $\partial
Y_1$ and $\partial Y_2$ are isometric in the metrics $\rho_{Y_j}$, $j = 1,2$.
There appears the following natural question: Under which additional conditions
are the boundaries $\partial Y_1$ and $\partial Y_2$ of $Y_1$ and $Y_2$
isometric in the metric $\rho_X$ of the ambient manifold $X$? The paper is
devoted to the detailed discussions of this question. In it, we in particular
obtain a number of new results concerning the rigidity problems for the
boundaries of $C^0$-submanifolds in a Riemannian manifold. The case of $\dim
Y_j = \dim X = n$, $n > 2$, is also considered.


title: The Simple Exclusion Process on the Circle has a diffusive Cutoff Window

abstract:
  In this paper, we investigate the mixing time of the simple exclusion process
on the circle with $N$ sites, with a number of particle $k(N)$ tending to
infinity, both from the worst initial condition and from a typical initial
condition. We show that the worst-case mixing time is asymptotically equivalent
to $(8\pi^2)^{-1}N^2\log k$, while the cutoff window, is identified to be
$N^2$. Starting from a typical condition, we show that there is no cutoff and
that the mixing time is of order $N^2$.


title: Phenomenological phase diagram of superfluid 3He in a stretched aerogel

abstract:
  Highly anisotropic "nematically ordered" aerogel induces global uniaxial
anisotropy in superfluid 3He. The anisotropy lowers symmetry of 3He in aerogel
from spherical to axial. As a result instead of one transition temperature in
the state, characterized by the orbital moment l=1 there are two, corresponding
to projections l_z=o and l_z=\pm 1. The splitting of transition has a
pronounced effect on the phase diagram of superfluid 3He and on a structures of
appearing phases. Possible phase diagrams, obtained phenomenologically on a
basis of Landau expansion of thermodynamic potential in a vicinity of the
transition temperature are presented here. The order parameters, corresponding
to each phase and their temperature dependencies are found.


title: Post-inflationary preheating with weak coupling

abstract:
  Particle production in the background of an external classical oscillating
field is a key process describing the stage of preheating after inflation. For
sufficiently strong couplings between the inflaton and matter fields, this
process is known to proceed non-perturbatively. Parametric resonance plays
crucial role for bosonic fields in this case, and the evolution of the
occupation numbers for fermions is non-perturbative as well. In the Minkowski
space, parametric resonance for bosons and non-perturbative effects for
fermions would still persist even in the case of weak coupling. In particular,
the energy density of created bosons would grow exponentially with time.
However, the situation is quite different in the expanding universe. We give a
simple demonstration how the conditions of the expanding universe,
specifically, redshift of the field modes, lead to the usual perturbative
expressions for particle production by an oscillating inflaton in the case of
weak couplings. The results that we obtain are relevant and fully applicable to
the Starobinsky model of inflation.


title:
Mineralogical Characteristics of Specimens of a Meteorwrong Fall from NW
  Iran

abstract:
  In the early hours of October 22, 2011, people of a small town in NW Iran,
called Khameneh (38{\deg}11'47" N, 45{\deg}38'14" E) noticed sounds of some
colliding objects to home roofs and yard floors. Mineralogical investigations
revealed the terrestrial and man-made origin of these stony samples.


title: $C^\ast$-simple groups without free subgroups

abstract:
  We construct first examples of non-trivial groups without non-cyclic free
subgroups whose reduced $C^\ast$-algebra is simple and has unique trace. This
answers a question of de la Harpe. Both torsion and torsion free examples are
provided. In particular, we show that the reduced $C^\ast$-algebra of the free
Burnside group $B(m,n)$ of rank $m\ge 2$ and any sufficiently large odd
exponent $n$ is simple and has unique trace.


title:
Filtered geometric lattices and Lefschetz Section Theorems over the
  tropical semiring

abstract:
  The purpose of this paper is to establish analogues of the classical
Lefschetz Section Theorem for smooth tropical varieties. More precisely, we
prove tropical analogues of the section theorems of Lefschetz,
Andreotti-Frankel, Bott-Milnor-Thom, Hamm-L\^e and Kodaira-Spencer, and the
vanishing theorems of Andreotti-Frankel and Akizuki-Kodaira-Nakano.
  We start the paper by resolving a conjecture of Mikhalkin and Ziegler (2008)
concerning the homotopy types of certain filtrations of geometric lattices,
generalizing several known properties of full geometric lattices. This
translates to a crucial index estimate for the stratified Morse data at
critical points of the tropical variety; it can also by itself be interpreted
as a Lefschetz-type theorem for matroids.


title: Selective Categories and Linear Canonical Relations

abstract:
  A construction of Wehrheim and Woodward circumvents the problem that
compositions of smooth canonical relations are not always smooth, building a
category suitable for functorial quantization. To apply their construction to
more examples, we introduce a notion of highly selective category, in which
only certain morphisms and certain pairs of these morphisms are "good". We then
apply this notion to the category $\mathbf{SLREL}$ of linear canonical
relations and the result ${\rm WW}(\mathbf{SLREL})$ of our version of the WW
construction, identifying the morphisms in the latter with pairs $(L,k)$
consisting of a linear canonical relation and a nonnegative integer. We put a
topology on this category of indexed linear canonical relations for which
composition is continuous, unlike the composition in $\mathbf{SLREL}$ itself.
Subsequent papers will consider this category from the viewpoint of derived
geometry and will concern quantum counterparts.


title: The extended locus of Hodge classes

abstract:
  We introduce an "extended locus of Hodge classes" that also takes into
account integral classes that become Hodge classes "in the limit". More
precisely, given a polarized variation of integral Hodge structure of weight
zero on a Zariski-open subset of a complex manifold, we construct a canonical
analytic space that parametrizes limits of integral classes; the extended locus
of Hodge classes is an analytic subspace that contains the usual locus of Hodge
classes, but is finite and proper over the base manifold. The construction uses
Saito's theory of mixed Hodge modules and a small generalization of the main
technical result of Cattani, Deligne, and Kaplan. We study the properties of
the resulting analytic space in the case of the family of hyperplane sections
of an odd-dimensional smooth projective variety.


title: How Best to Handle a Dicey Situation

abstract:
  We introduce the {Destructive Object Handling} (DOH) problem, which models
aspects of many real-world allocation problems, such as shipping explosive
munitions, scheduling processes in a cluster with fragile nodes, re-using
passwords across multiple websites, and quarantining patients during a disease
outbreak. In these problems, objects must be assigned to handlers, but each
object has a probability of destroying itself and all the other objects
allocated to the same handler. The goal is to maximize the expected value of
the objects handled successfully.
  We show that finding the optimal allocation is
$\mathsf{NP}$-$\mathsf{complete}$, even if all the handlers are identical. We
present an FPTAS when the number of handlers is constant. We note in passing
that the same technique also yields a first FPTAS for the weapons-target
allocation problem \cite{manne_wta} with a constant number of targets. We study
the structure of DOH problems and find that they have a sort of phase
transition -- in some instances it is better to spread risk evenly among the
handlers, in others, one handler should be used as a ``sacrificial lamb''. We
show that the problem is solvable in polynomial time if the destruction
probabilities depend only on the handler to which an object is assigned; if all
the handlers are identical and the objects all have the same value; or if each
handler can be assigned at most one object.
  Finally, we empirically evaluate several heuristics based on a combination of
greedy and genetic algorithms. The proposed heuristics return fairly high
quality solutions to very large problem instances (upto 250 objects and 100
handlers) in tens of seconds.


title: Ab initio investigation of lasing thresholds in photonic molecules

abstract:
  We investigate lasing thresholds in a representative photonic molecule
composed of two coupled active cylinders of slightly different radii.
Specifically, we use the recently formulated steady-state ab initio laser
theory (SALT) to assess the effect of the underlying gain transition on lasing
frequencies and thresholds. We find that the order in which modes lase can be
modified by choosing suitable combinations of the gain center frequency and
linewidth, a result that cannot be obtained using the conventional approach of
quasi-bound modes. The impact of the gain transition center on the lasing
frequencies, the frequency pulling effect, is also quantified.


title: Transport and Accretion in Planet-Forming Disks

abstract:
  Planets appear to form in environments shaped by the gas flowing through
protostellar disks to the central young stars. The flows in turn are governed
by orbital angular momentum transfer. In this chapter we summarize current
understanding of the transfer processes best able to account for the flows,
including magneto-rotational turbulence, magnetically-launched winds,
self-gravitational instability and vortices driven by hydrodynamical
instabilities. For each in turn we outline the major achievements of the past
few years and the outstanding questions. We underscore the requirements for
operation, especially ionization for the magnetic processes and heating and
cooling for the others. We describe the distribution and strength of the
resulting flows and compare with the long-used phenomenological
$\alpha$-picture, highlighting issues where the fuller physical picture yields
substantially different answers. We also discuss the links between magnetized
turbulence and magnetically-launched outflows, and between magnetized
turbulence and hydrodynamical vortices. We end with a summary of the status of
efforts to detect specific signatures of the flows.


title: Quantum mechanics of null polygonal Wilson loops

abstract:
  Scattering amplitudes in maximally supersymmetric gauge theory are dual to
super-Wilson loops on null polygonal contours. The operator product expansion
for the latter revealed that their dynamics is governed by the evolution of
multiparticle GKP excitations. They were shown to emerge from the spectral
problem of an underlying open spin chain. In this work we solve this model with
the help of the Baxter Q-operator and Sklyanin's Separation of Variables
methods. We provide an explicit construction for eigenfunctions and eigenvalues
of GKP excitations. We demonstrate how the former define the so-called
multiparticle hexagon transitions in super-Wison loops and prove their
factorized form suggested earlier.


title:
Self-consistent theory of Bose-Einstein condensate with impurity at
  finite temperature

abstract:
  We study the properties of Bose-Einstein condensate (BEC)-impurity mixtures
at finite temperature employing the Balian-V\'en\'eroni (BV) variational
principle. The method leads to a set of coupled nonlinear equations of motion
for the condensate and its normal and anomalous fluctuations on the one hand,
and for the impurity on the other. We show that the obtained equations satisfy
the energy and number conserving laws. Useful analytic expressions for the
chemical potential and the radius of both condensate and anomalous components
are derived in the framework of the Thomas-Fermi (TF) approximation in
$d$-dimensional regime. Effects of the impurity on these quantities are
discussed.


title: Tuning, Ergodicity, Equilibrium and Cosmology

abstract:
  I explore the possibility that the cosmos is fundamentally an equilibrium
system, and review the attractive features of such theories. Equilibrium
cosmologies are commonly thought to fail due to the ``Boltzmann Brain''
problem. I show that it is possible to evade the Boltzmann Brain problem if
there is a suitable coarse grained relationship between the fundamental degrees
of freedom and the cosmological observables. I make my main points with simple
toy models, and then review the de Sitter equilibrium model as an illustration.


title: Why is Universe so dark ?

abstract:
  In this presentation prepared for a general audience, we briefly mention the
shortcomings of standard model of universe. We then focus on the late time
inconsistency of the model dubbed age crisis whose resolution requires the
presence of a repulsive effect that could be sourced either by dark energy or
by a large scale modification of gravity. By and large, our description is
based upon Newtonian cosmology which is simple and elegant despite of its
limitations. On heuristic grounds, we explain how a tiny mass of graviton could
account for late time cosmic acceleration. We also include a brief discussion
on the underlying physics of Type Ia supernovae explosion and the direct
confirmation of late time acceleration of Universe by the related observations.


title: Flow pattern in the vicinity of self-propelling hot Janus particles

abstract:
  We study the temperature field and the resulting flow pattern in the vicinity
of a heated metal-capped Janus particle. If its thickness exceeds about 10 nm,
the cap forms an isotherm and the flow pattern comprises a quadrupolar term
that decays with the square of the inverse distance 1/r^2. For much thinner
caps the velocity varies as 1/r^3. These findings could be relevant for
collective effects in dense suspensions and for the circular tracer motion
observed recently in the vicinity of a tethered Janus particle.


title:
A new proposal regarding the heat generated by gravity in locally
  accelerating frames

abstract:
  For Rindler observers accelerating close to the horizon in local patches
around a spacetime point, the matter-energy passing through the horizon
increases the entropy and heat energy. Jacobson has showed that the Einstein
equation can be derived from the consideration of this thermodynamic process.
This, however, works only if the acceleration $a$ is much larger than the scale
set by the curvature of the spacetime. It is explored here whether an extension
is possible to the case with no lower bound on $a$. We show that this is
possible if one assumes that in a locally accelerating frame, the matter-energy
passing through null hypersurfaces could result in an increase in the heat
energy and the entropy. Such a generalisation extends the thermodynamic
derivation of gravity to include any non-freely falling observer. A new method
of determining the temperature detected by such locally accelerating observers
is also presented. By considering only the quantisation of sufficiently
localised wave modes of a field, it is shown that the observer finds himself in
a thermal environment.


title: Deterministic Blind Rendezvous in Cognitive Radio Networks

abstract:
  Blind rendezvous is a fundamental problem in cognitive radio networks. The
problem involves a collection of agents (radios) that wish to discover each
other in the blind setting where there is no shared infrastructure and they
initially have no knowledge of each other. Time is divided into discrete slots;
spectrum is divided into discrete channels, $\{1,2,..., n\}$. Each agent may
access a single channel in a single time slot and we say that two agents
rendezvous when they access the same channel in the same time slot. The model
is asymmetric: each agent $A_i$ may only use a particular subset $S_i$ of the
channels and different agents may have access to different subsets of channels.
The goal is to design deterministic channel hopping schedules for each agent so
as to guarantee rendezvous between any pair of agents with overlapping channel
sets.
  Two independent sets of authors, Shin et al. and Lin et al., gave the first
constructions guaranteeing asynchronous blind rendezvous in $O(n^2)$ and
$O(n^3)$ time, respectively. We present a substantially improved construction
guaranteeing that any two agents, $A_i$, $A_j$, will rendezvous in $O(|S_i|
|S_j| \log\log n)$ time. Our results are the first that achieve nontrivial
dependence on $|S_i|$, the size of the set of available channels. This allows
us, for example, to save roughly a quadratic factor over the best previous
results in the important case when channel subsets have constant size. We also
achieve the best possible bound of $O(1)$ time for the symmetric situation;
previous works could do no better than $O(n)$. Using the probabilistic method
and Ramsey theory we provide evidence in support of our suspicion that our
construction is asymptotically optimal for small size channel subsets: we show
both a $c |S_i||S_j|$ lower bound and a $c \log\log n$ lower bound when $|S_i|,
|S_j| \leq n/2$.


title:
Self-duality and associated parallel or cocalibrated ${\mathrm{G}}_2$
  structures

abstract:
  We find a remarkable family of $\mathrm{G}_2$ structures defined on certain
principal $\mathrm{SO}(3)$-bundles $P_\pm\longrightarrow M$ associated with any
given oriented Riemannian 4-manifold $M$. Such structures are always
cocalibrated. The study starts with a recast of the Singer-Thorpe equations of
4-dimensional geometry. These are applied to the Bryant-Salamon cons\-truction
of complete $\mathrm{G}_2$-holonomy metrics on the vector bundle of self- or
anti-self-dual 2-forms on $M$. We then discover new examples of that special
holonomy on disk bundles over ${\cal H}^4$ and ${\cal H}^2_{\mathbb{C}}$,
respectively, the real and complex hyperbolic space. Only in the end we present
the new $\mathrm{G}_2$ structures on principal bundles.


title:
On the quantitative quasi-isometry problem: transport of Poincar\'e
  inequalities and different types of quasi-isometric distortion growth

abstract:
  We consider a quantitative form of the quasi-isometry problem. We discuss
several arguments which lead us to different results and bounds of
quasi-isometric distortion: comparison of volumes, connectivity etc. Then we
study the transport of Poincar\'e constants by quasi-isometries and we give
sharp lower and upper bounds for the homotopy distortion growth for an
interesting class of hyperbolic metric spaces.


title:
Moderate Deviation Principles for Stochastic Differential Equations with
  Jumps

abstract:
  Moderate deviation principles for stochastic differential equations driven by
a Poisson random measure (PRM) in finite and infinite dimensions are obtained.
Proofs are based on a variational representation for expected values of
positive functionals of a PRM.


title:
Asymptotic states and renormalization in Lorentz-violating quantum field
  theory

abstract:
  Asymptotic single-particle states in quantum field theories with small
departures from Lorentz symmetry are investigated perturbatively with focus on
potential phenomenological ramifications. To this end, one-loop radiative
corrections for a sample Lorentz-violating Lagrangian contained in the
Standard-Model Extension (SME) are studied at linear order in Lorentz
breakdown. It is found that the spinor kinetic operator, and thus the
free-particle physics, is modified by Lorentz-violating operators absent from
the original Lagrangian. As a consequence of this result, both the standard
renormalization procedure as well as the Lehmann-Symanzik-Zimmermann reduction
formalism need to be adapted. The necessary adaptations are worked out
explicitly at first order in Lorentz-breaking coefficients.


title: The Mabuchi Completion of the Space of K\"ahler Potentials

abstract:
  Suppose $(X,\omega)$ is a compact K\"ahler manifold. Following Mabuchi, the
space of smooth K\"ahler potentials $\mathcal H$ can be endowed with a
Riemannian structure, which induces an infinite dimensional path length metric
space $(\mathcal H,d)$. We prove that the metric completion of $(\mathcal H,d)$
can be identified with $(\mathcal E^2(X,\omega),\tilde d)$, and this latter
space is a complete non-positively curved geodesic metric space. In obtaining
this result, we will rely on envelope techniques which allow for a treatment in
a very general context. Profiting from this, we will characterize the pairs of
potentials in $\text{PSH}(X,\omega)$ that can be connected by weak geodesics
and we will also give a characterization of $\mathcal E(X,\omega)$ in this
context.


title: Relational symplectic groupoids

abstract:
  This note introduces the construction of relational symplectic groupoids as a
way to integrate every Poisson manifold. Examples are provided and the
equivalence, in the integrable case, with the usual notion of symplectic
groupoid is discussed.


title:
Different Strategies for Optimization Using the Quantum Adiabatic
  Algorithm

abstract:
  We present the results of a numerical study, with 20 qubits, of the
performance of the Quantum Adiabatic Algorithm on randomly generated instances
of MAX 2-SAT with a unique assignment that maximizes the number of satisfied
clauses. The probability of obtaining this assignment at the end of the quantum
evolution measures the success of the algorithm. Here we report three
strategies which consistently increase the success probability for the hardest
instances in our ensemble: decreasing the overall evolution time, initializing
the system in excited states, and adding a random local Hamiltonian to the
middle of the evolution.


title: Flux Compactifications on $(S_2)^N$

abstract:
  We investigate a simple extra-dimensional model and its four-dimensional
vacua. This model has a two-form flux and a positive cosmological constant, and
the extra dimensions are compactified as the product of $N$ two-spheres. The
theory is an interesting laboratory because it is at once simple enough to be
soluble but rich enough to exhibit many features not present in previous model
landscapes.


title:
The evolution of massive stars and their spectra I. A non-rotating 60
  Msun star from the zero-age main sequence to the pre-supernova stage

abstract:
  For the first time, the interior and spectroscopic evolution of a massive
star is analyzed from the zero-age main sequence (ZAMS) to the pre-supernova
(SN) stage. For this purpose, we combined stellar evolution models using the
Geneva code and atmospheric models using CMFGEN. With our approach, we were
able to produce observables, such as a synthetic high-resolution spectrum and
photometry, aiding the comparison between evolution models and observed data.
Here we analyze the evolution of a non-rotating 60 Msun star and its spectrum
throughout its lifetime. Interestingly, the star has a supergiant appearance
(luminosity class I) even at the ZAMS. We find the following evolutionary
sequence of spectral types: O3 I (at the ZAMS), O4 I (middle of the H-core
burning phase), B supergiant (BSG), B hypergiant (BHG), hot luminous blue
variable (LBV; end of H-core burning), cool LBV (H-shell burning through the
beginning of the He-core burning phase), rapid evolution through late WN and
early WN, early WC (middle of He-core burning), and WO (end of He-core burning
until core collapse). We find the following spectroscopic phase lifetimes:
3.22e6 yr for the O-type, 0.34e5 yr (BSG), 0.79e5 yr (BHG), 2.35e5 yr (LBV),
1.05e5 yr (WN), 2.57e4 yr (WC), and 3.80e4 yr (WO). Compared to previous
studies, we find a much longer (shorter) duration for the early WN (late WN)
phase, as well as a long-lived LBV phase. We show that LBVs arise naturally in
single-star evolution models at the end of the MS when the mass-loss rate
increases as a consequence of crossing the bistability limit. We discuss the
evolution of the spectra, magnitudes, colors, and ionizing flux across the
star's lifetime, and the way they are related to the evolution of the interior.
[abridged]


title:
Insensitizing exact controls for the scalar wave equation and exact
  controllability of $2$-coupled cascade systems of PDE's by a single control

abstract:
  We study the exact controllability, by a reduced number of controls, of
coupled cascade systems of PDE's and the existence of exact insensitizing
controls for the scalar wave equation. We give a necessary and sufficient
condition for the observability of abstract coupled cascade hyperbolic systems
by a single observation, the observation operator being either bounded or
unbounded. Our proof extends the two-level energy method introduced in
\cite{sicon03, alaleau11} for symmetric coupled systems, to cascade systems
which are examples of non symmetric coupled systems. In particular, we prove
the observability of two coupled wave equations in cascade if the observation
and coupling regions both satisfy the Geometric Control Condition (GCC) of
Bardos Lebeau and Rauch \cite{blr92}. By duality, this solves the exact
controllability, by a single control, of $2$-coupled abstract cascade
hyperbolic systems. Using transmutation, we give null-controllability results
for the multidimensional heat and Schr\"odinger $2$-coupled cascade systems
under (GCC) and for any positive time. By our method, we can treat cases where
the control and coupling coefficients have disjoint supports, partially solving
an open question raised by de Teresa \cite{DeT00}. Moreover we answer the
question of the existence of exact insensitizing locally distributed as well as
boundary controls of scalar multidimensional wave equations, raised by J.-L.
Lions \cite{lions89} and later on by D\'ager \cite{Dager06} and Tebou
\cite{tebou08}.


title:
Development of large-area quadrant silicon detector for charged
  particles

abstract:
  The quadrant silicon detector, a kind of passivated implanted planar silicon
detector with quadrant structure on the junction side, gained its wide
application in charged particle detection. In this paper, the manufacturing
procedure, performance test and results of the quadrant silicon detector
developed recently at the China Institute of Atomic Energy are presented. The
detector is about 300 $\mu$m thick with a 48$\times$48 mm$^{2}$ active area.
The leakage current under full depletion bias voltage of -16 V is about 2.5 nA,
and the raising time is better than 160 ns. The energy resolution for 5.157 MeV
$\alpha$-particle is around the level of $1\%$. Charge sharing effects between
the neighboring quads, leading to complicated correlations between two quads,
were observed when $\alpha$ particles illuminated on the junction side. It is
explained as a result of distortion of electric field of inter-quad region.
Such events is only about $0.6\%$ of all events and can be neglected in an
actual application.


title:
The extreme chemistry of multiple stellar populations in the metal-poor
  globular cluster NGC 4833

abstract:
  Our FLAMES survey of Na-O anticorrelation in globular clusters (GCs) is
extended to NGC 4833, a metal-poor GC with a long blue tail on the horizontal
branch (HB). We present the abundance analysis for a large sample of 78 red
giants based on UVES and GIRAFFE spectra acquired at the ESO-VLT. We derived
abundances of Na, O, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y,
Ba, La, Nd. This is the first extensive study of this cluster from high
resolution spectroscopy. On the scale of our survey, the metallicity of NGC
4833 is [Fe/H]=-2.015+/-0.004+/-0.084 dex (rms=0.014 dex) from 12 stars
observed with UVES, where the first error is from statistics and the second one
refers to the systematic effects. The iron abundance in NGC 4833 is homogeneous
at better than 6%. On the other hand, the light elements involved in
proton-capture reactions at high temperature show the large star-to-star
variations observed in almost all GCs studied so far. The Na-O anticorrelation
in NGC 4833 is quite extended, as expected from the high temperatures reached
by stars on the HB, and NGC 4833 contains a conspicuous fraction of stars with
extreme [O/Na] ratios. More striking is the finding that large star-to-star
variations are seen also for Mg, which spans a range of more than 0.5 dex in
this GC. Depletions in Mg are correlated to the abundances of O and
anti-correlated with Na, Al, and Si abundances. This pattern suggests the
action of nuclear processing at unusually high temperatures, producing the
extreme chemistry observed in the stellar generations of NGC 4833. This extreme
changes are also seen in giants of the much more massive GCs M 54 and omega
Cen, and our conclusion is that NGC 4833 has probably lost a conpicuous
fraction of its original mass due to bulge shocking, as also indicated by its
orbit.


title:
Signatures of very massive stars: supercollapsars and their cosmological
  rate

abstract:
  We compute the rate of supercollapsars by using cosmological, N-body, hydro,
chemistry simulations of structure formation, following detailed stellar
evolution according to proper yields (for He, C, N, O, Si, S, Fe, Mg, Ca, Ne,
etc.) and lifetimes for stars having different masses and metallicities, and
for different stellar populations (population III and population II-I). We find
that supercollapsars are usually associated to dense, collapsing gas with
little metal pollution and with abundances dominated by oxygen. The resulting
supercollapsar rate is about $10^{-2}\,\rm yr^{-1} sr^{-1}$ at redshift $z=0$,
and their contribution to the total rate is $ < 0.1 $ per cent, which explains
why they have never been detected so far. Expected rates at redshift $z\simeq
6$ are of the order of $\sim 10^{-3}\,\rm yr^{-1} sr^{-1}$ and decrease further
at higher $z$. Because of the strong metal enrichment by massive, short-lived
stars, only $\sim 1$ supercollapsar generation is possible in the same star
forming region. Given their sensitivity to the high-mass end of the primordial
stellar mass function, they are suitable candidates to probe pristine
population III star formation and stellar evolution at low metallicities.


title: The Higgs Mass and the Stueckelberg Mechanism in Supersymmetry

abstract:
  We investigate a class of theories where the mass of the lightest Higgs boson
of the Minimal Supersymmetric Standard Model (MSSM) can be larger than the Z
gauge boson mass at tree level. In this context the MSSM fields feel a new
force, whose corresponding gauge boson attains its mass through the
Stueckelberg mechanism. We show how one can achieve a Higgs mass around 126 GeV
without assuming a heavy stop spectrum or a large stop trilinear term. The
application of this class of models to the conservation of R-parity is also
discussed.


title:
From Voids to Coma: the prevalence of pre-processing in the local
  Universe

abstract:
  We examine the effects of pre-processing across the Coma Supercluster,
including 3505 galaxies over 500 sq deg, by quantifying the degree to which
star-forming (SF) activity is quenched as a function of environment. We
characterise environment using the complementary techniques of Voronoi
Tessellation, to measure the density field, and the Minimal Spanning Tree, to
define continuous structures, and so we measure SF activity as a function of
local density and the type of environment (cluster, group, filament, and void),
and quantify the degree to which environment contributes to quenching of SF
activity. Our sample covers over two orders of magnitude in stellar mass
(10^8.5 to 10^11 Msun), and consequently we trace the effects of environment on
SF activity for dwarf and massive galaxies, distinguishing so-called "mass
quenching" from "environment quenching". Environmentally-driven quenching of SF
activity, measured relative to the void galaxies, occurs to progressively
greater degrees in filaments, groups, and clusters, and this trend holds for
dwarf and massive galaxies alike. A similar trend is found using g-r colours,
but with a more significant disparity between galaxy mass bins driven by
increased internal dust extinction in massive galaxies. The SFR distributions
of massive SF galaxies have no significant environmental dependence, but the
distributions for dwarf SF galaxies are found to be statistically distinct in
most environments. Pre-processing plays a significant role at low redshift, as
environmentally-driven galaxy evolution affects nearly half of the galaxies in
the group environment, and a significant fraction of the galaxies in the more
diffuse filaments. Our study underscores the need for sensitivity to dwarf
galaxies to separate mass-driven from environmentally-driven effects, and the
use of unbiased tracers of SF activity.


title:
Stellar mass -- halo mass relation and star formation efficiency in
  high-mass halos

abstract:
  We study relation between stellar mass and halo mass for high-mass halos
using a sample of galaxy clusters with accurate measurements of stellar masses
from optical and IR data and total masses from X-ray observations. We find that
stellar mass of the brightest cluster galaxies (BCGs) scales as M*BCG\propto
M500^a_BCG with the best fit slope of a_BCG~0.35+-0.1 and scatter of M*BCG at a
fixed M500 of ~0.2 dex. We show that M*-M relations from abundance matching or
halo modelling reported in recent studies underestimate stellar masses of BCGs
by a factor of ~2-4, because these studies used stellar mass functions (SMF)
based on photometry that severely underestimates the outer surface brightness
profiles of massive galaxies. We show that M*-M relation derived using
abundance matching with the recent SMF calibration by Bernardi et al. (2013)
based on improved photometry is in a much better agreement with the relation we
derive. The total stellar mass of galaxies correlates with total mass M500 with
the slope of \approx 0.6+-0.1 and scatter of 0.1 dex. This indicates that
efficiency with which baryons are converted into stars decreases with
increasing cluster mass. We show that for a fixed choice of the initial mass
function (IMF) total stellar fraction in clusters is only a factor of ~3-5
lower than the peak stellar fraction reached in M\approx 10^12 Msun halos, and
only a factor of ~1.5-3 if the IMF becomes progressively more bottom heavy with
increasing mass in early type galaxies, as indicated by recent observations.
The larger normalization and slope of the M*-M relation derived in this study
shows that the overall efficiency of star formation in massive halos is
suppressed much less than was thought before and that feedback and associated
suppression of star formation in massive halos should be weaker than assumed in
most of the current semi-analytic models and simulations.


title: Sensitivity of CTA to dark matter signals from the Galactic Center

abstract:
  (abridged) The Galactic Center is one of the most promising targets for
indirect detection of dark matter with gamma rays. We investigate the
sensitivity of the upcoming Cherenkov Telescope Array (CTA) to dark matter
annihilation and decay in the Galactic Center. As the inner density profile of
the Milky Way's dark matter halo is uncertain, we study the impact of the slope
of the Galactic density profile, inwards of the Sun, on the prospects for
detecting a dark matter signal with CTA. We find that the sensitivity achieved
by CTA to annihilation signals is strongly dependent on the inner profile
slope, whereas the dependence is more mild in the case of dark matter decay.
Surprisingly, we find that the optimal choice of signal and background regions
is virtually independent of the assumed density profile. For the fiducial case
of a Navarro-Frenk-White profile, we find that CTA will be able to probe
annihilation cross sections well below the canonical thermal relic value for
dark matter masses from a few tens of GeV up to $\sim 5$ TeV for annihilation
to $\tau^{+}\tau^{-}$, and will achieve only a slightly weaker sensitivity for
annihilation to $b\bar{b}$ or $\mu^{+}\mu^{-}$. CTA will improve significantly
on current sensitivity to annihilation signals for dark matter masses above
$\sim 100$ GeV, covering parameter space that is complementary to that probed
by searches with the Fermi Large Area Telescope. The interpretation of apparent
excesses in the measured cosmic-ray electron and positron spectra as signals of
dark matter decay will also be testable with CTA observations of the Galactic
Center. We demonstrate that both for annihilation and for decay, including
spectral information for hard channels (such as $\mu^{+}\mu^{-}$ and
$\tau^{+}\tau^{-}$) leads to enhanced sensitivity for dark matter masses above
$m_{\rm DM}\sim 200$ GeV.

categories: astro-ph.HE astro-ph.CO astro-ph.GA hep-ph


title:
Galaxy and Mass Assembly (GAMA): Fine filaments of galaxies detected
  within voids

abstract:
  Based on data from the Galaxy and Mass Assembly (GAMA) survey, we report on
the discovery of structures that we refer to as `tendrils' of galaxies:
coherent, thin chains of galaxies that are rooted in filaments and terminate in
neighbouring filaments or voids. On average, tendrils contain 6 galaxies and
span 10 $h^{-1}$ Mpc. We use the so-called line correlation function to prove
that tendrils represent real structures rather than accidental alignments. We
show that voids found in the SDSS-DR7 survey that overlap with GAMA regions
contain a large number of galaxies, primarily belonging to tendrils. This
implies that void sizes are strongly dependent on the number density and
sensitivity limits of a survey. We caution that galaxies in low density
regions, that may be defined as `void galaxies,' will have local galaxy number
densities that depend on such observational limits and are likely higher than
can be directly measured.


title:
Early X-ray emission from Type Ia supernovae originating from symbiotic
  progenitors or recurrent novae

abstract:
  One of the key observables for determining the progenitor nature of Type Ia
supernovae is provided by their immediate circumstellar medium, which according
to several models should be shaped by the progenitor binary system. So far,
X-ray and radio observations indicate that the surroundings are very tenuous,
producing severe upper-limits on the mass loss from winds of the progenitors.
In this study, we perform numerical hydro-dynamical simulations of the
interaction of the SN ejecta with circumstellar structures formed by possible
mass outflows from the progenitor systems and we estimate numerically the
expected numerical X-ray luminosity. We consider two kinds of circumstellar
structures: a) A circumstellar medium formed by the donor star's stellar wind,
in case of a symbiotic binary progenitor system; b) A circumstellar medium
shaped by the interaction of the slow wind of the donor star with consecutive
nova outbursts for the case of a symbiotic recurrent nova progenitor system.
For the hydro-simulations we used well-known Type Ia supernova explosion
models, as well as an approximation based on a power law model for the density
structure of the outer ejecta. We confirm the strict upper limits on stellar
wind mass loss, provided by simplified interpretations of X-ray upper limits of
Type Ia supernovae. However, we show that supernova explosions going off in the
cavities created by repeated nova explosions, provide a possible explanation
for the lack of X-ray emission from supernovae originating from symbiotic
binaries. Moreover, the velocity structure of circumstellar medium, shaped by a
series of nova explosion matches well with the Na absorption features seen in
absorption toward several Type Ia supernovae.


title:
Ionization compression impact on dense gas distribution and star
  formation, Probability density functions around H ii regions as seen by
  Herschel

abstract:
  Ionization feedback should impact the probability distribution function (PDF)
of the column density around the ionized gas. We aim to quantify this effect
and discuss its potential link to the Core and Initial Mass Function (CMF/IMF).
We used in a systematic way Herschel column density maps of several regions
observed within the HOBYS key program: M16, the Rosette and Vela C molecular
cloud, and the RCW 120 H ii region. We fitted the column density PDFs of all
clouds with two lognormal distributions, since they present a double-peak or
enlarged shape in the PDF. Our interpretation is that the lowest part of the
column density distribution describes the turbulent molecular gas while the
second peak corresponds to a compression zone induced by the expansion of the
ionized gas into the turbulent molecular cloud. The condensations at the edge
of the ionized gas have a steep compressed radial profile, sometimes
recognizable in the flattening of the power-law tail. This could lead to an
unambiguous criterion able to disentangle triggered from pre-existing star
formation. In the context of the gravo-turbulent scenario for the origin of the
CMF/IMF, the double peaked/enlarged shape of the PDF may impact the formation
of objects at both the low-mass and the high-mass end of the CMF/IMF. In
particular a broader PDF is required by the gravo-turbulent scenario to fit
properly the IMF with a reasonable initial Mach number for the molecular cloud.
Since other physical processes (e.g. the equation of state and the variations
among the core properties) have already been suggested to broaden the PDF, the
relative importance of the different effects remains an open question.


title: Halo Mass Definition and Multiplicity Function

abstract:
  Comparing the excursion set and CUSP formalisms for the derivation of the
halo mass function, we investigate the role of the mass definition in the
properties of the multiplicity function of cold dark matter (CDM) haloes. We
show that the density profile for haloes formed from triaxial peaks that
undergo ellipsoidal collapse and virialisation is such that the ratio between
the mean inner density and the outer local density is essentially independent
of mass. This causes that, for suited values of the spherical overdensity
$\Delta$ and the linking length $b$, SO and FoF masses are essentially
equivalent to each other and the respective multiplicity functions are
essentially the same. The overdensity for haloes having undergone ellipsoidal
collapse is the same as if they had formed according to the spherical top-hat
model, which leads to a value of $b$ corresponding to the usual virial
overdensity, $\Delta_{vir}$, equal to $\sim$ 0.2. The multiplicity function
resulting from such mass definitions, expressed as a function of the top-hat
height for spherical collapse, is very approximately universal in all CDM
cosmologies. The reason for this is that, for such mass definitions, the
top-hat density contrast for ellipsoidal collapse and virialisation is close to
a universal value, equal to $\sim$ 0.9 times the usual top-hat density contrast
for spherical collapse.


title:
Fixing a Rigorous Formalism for the Accurate Analytic Derivation of Halo
  Properties

abstract:
  We establish a one-to-one correspondence between virialized haloes and their
seeds, namely peaks with a given density contrast at appropriate
Gaussian-filtering radii, in the initial Gaussian random density field. This
fixes a rigorous formalism for the analytic derivation of halo properties from
the linear power spectrum of density perturbations in any hierarchical
cosmology. The typical spherically averaged density profile and mass function
of haloes so obtained match those found in numerical simulations.


title:
Stellar Kinematics and Structural Properties of Virgo Cluster Dwarf
  Early-Type Galaxies from the SMAKCED Project. I. Kinematically Decoupled
  Cores and Implications for Infallen Groups in Clusters

abstract:
  We present evidence for kinematically decoupled cores (KDCs) in two dwarf
early-type (dE) galaxies in the Virgo cluster, VCC 1183 and VCC 1453, studied
as part of the SMAKCED stellar absorption-line spectroscopy and imaging survey.
These KDCs have radii of 1.8'' (0.14 kpc) and 4.2'' (0.33 kpc), respectively.
Each of these KDCs is distinct from the main body of its host galaxy in two
ways: (1) inverted sense of rotation; and (2) younger (and possibly more
metal-rich) stellar population. The observed stellar population differences are
probably associated with the KDC, although we cannot rule out the possibility
of intrinsic radial gradients in the host galaxy. We describe a statistical
analysis method to detect, quantify the significance of, and characterize KDCs
in long-slit rotation curve data. We apply this method to the two dE galaxies
presented in this paper and to five other dEs for which KDCs have been reported
in the literature. Among these seven dEs, there are four significant KDC
detections, two marginal KDC detections, and one dE with an unusual central
kinematic anomaly that may be an asymmetric KDC.The frequency of occurence of
KDCs and their properties provide important constraints on the formation
history of their host galaxies. We discuss different formation scenarios for
these KDCs in cluster environments and find that dwarf-dwarf wet mergers or gas
accretion can explain the properties of these KDCs. Both of these mechanisms
require that the progenitor had a close companion with a low relative velocity.
This suggests that KDCs were formed in galaxy pairs residing in a poor group
environment or in isolation whose subsequent infall into the cluster quenched
star formation.


title:
On quantitative noise stability and influences for discrete and
  continuous models

abstract:
  Keller and Kindler recently established a quantitative version of the famous
Benjamini~--Kalai--Schramm Theorem on noise sensitivity of Boolean functions.
The result was extended to the continuous Gaussian setting by Keller, Mossel
and Sen by means of a Central Limit Theorem argument. In this work, we present
an unified approach of these results, both in discrete and continuous settings.
The proof relies on semigroup decompositions together with a suitable cut-off
argument allowing for the efficient use of the classical hypercontractivity
tool behind these results. It extends to further models of interest such as
families of log-concave measures and Cayley and Schreier graphs. In particular
we obtain a quantitative version of the B-K-S Theorem for the slices of the
Boolean cube.


title: Stellar and Gaseous Nuclear Disks Observed in Nearby (U)LIRGs

abstract:
  We present near-infrared integral field spectroscopy of the central
kiloparsec of 17 nearby luminous and ultra-luminous infrared galaxies
undergoing major mergers. These observations were taken with OSIRIS assisted by
the Keck I and II Adaptive Optics systems, providing spatial resolutions of a
few tens of parsecs. The resulting kinematic maps reveal gas disks in at least
16 out of 19 nuclei and stellar disks in 11 out of 11 nuclei observed in these
galaxy merger systems. In our late-stages mergers, these disks are young
(stellar ages $<30$ Myr) and likely formed as gas disks which became unstable
to star formation during the merger. On average, these disks have effective
radii of a few hundred parsecs, masses between $10^{8}$ and $10^{10} M_{Sun}$,
and $v/\sigma$ between 1 and 5. These disks are similar to those created in
high-resolution hydrodynamical simulations of gas-rich galaxy mergers, and
favor short coalescence times for binary black holes. The few galaxies in our
sample in earlier stages of mergers have disks which are larger
($r_{eff}\sim200-1800$ pc) and likely are remnants of the galactic disks that
have not yet been completely disrupted by the merger.


title:
Distinguishing axions from generic light scalars using EDM and
  fifth-force experiments

abstract:
  We derive electric dipole moment (EDM) constraints on possible new
macroscopic time reversal and parity violating (TVPV) spin-dependent forces.
These constraints are compared to those derived from direct searches in
fifth-force experiments and from combining laboratory searches with
astrophysical bounds on stellar energy loss. For axion-mediated TVPV
spin-dependent forces, EDM constraints dominate over fifth-force limits by
several orders of magnitude. However, we show that for a generic light scalar,
unrelated to the strong CP problem, present bounds from direct fifth- force
searches are more stringent than those inferred from EDM limits, for the
interaction ranges explored by fifth-force experiments. Thus, correlating
observations in EDM and fifth-force experiments could help distinguish axions
from more generic light scalar scenarios.


title: Higgs pair production at the LHC with NLO and parton-shower effects

abstract:
  We present predictions for the SM-Higgs-pair production channels of relevance
at the LHC: gluon-gluon fusion, VBF, and top-pair, W, Z and single-top
associated production. All these results are at the NLO accuracy in QCD, and
matched to parton showers by means of the MC@NLO method; hence, they are fully
differential. With the exception of the gluon-gluon fusion process, for which a
special treatment is needed in order to improve upon the infinite-top-mass
limit, our predictions are obtained in a fully automatic way within the
publicly available MadGraph5_aMC@NLO framework. We show that for all channels
in general, and for gluon-gluon fusion and top-pair associated production in
particular, NLO corrections reduce the theoretical uncertainties, and are
needed in order to arrive at reliable predictions for total rates as well as
for distributions.


title:
Large-deviation statistics of a diffusive quantum spin chain and the
  additivity principle

abstract:
  Using the large-deviation formalism, we study the statistics of current
fluctuations in a diffusive nonequilibrium quantum spin chain. The
boundary-driven XX chain with dephasing consists of a coherent bulk hopping and
a local dissipative dephasing. We analytically calculate the exact expression
for the second current moment in a system of any length and then numerically
demonstrate that in the thermodynamic limit higher-order cumulants and the
large-deviation function can be calculated using the additivity principle or
macroscopic hydrodynamic theory. This shows that the additivity principle can
also hold in systems that are not purely stochastic, and can in particular be
valid in quantum systems. We also show that in large systems the current
fluctuations are the same as in the classical symmetric simple exclusion
process.


title:
MMT Hypervelocity Star Survey III: A Complete Survey of Faint B-type
  Stars in the Northern Milky Way Halo

abstract:
  We describe our completed spectroscopic survey for unbound hypervelocity
stars (HVSs) ejected from the Milky Way. Three new discoveries bring the total
number of unbound HVSs to 21. We place new constraints on the nature of HVSs
and on their distances using moderate resolution MMT spectroscopy. Half of the
HVSs are fast rotators; they are certain 2.5-4 Msun main sequence stars at 50 -
120 kpc distances. Correcting for stellar lifetime, our survey implies that
unbound 2.5-4 Msun stars are ejected from the Milky Way at a rate of 1.5e-6
/yr. The observed HVSs are likely ejected continuously over the past 200 Myr
and do not share a common flight time. The anisotropic spatial distribution of
HVSs on the sky remains puzzling. Southern hemisphere surveys like SkyMapper
will soon allow us to map the all-sky distribution of HVSs. Future proper
motion measurements with Hubble Space Telescope and Gaia will provide strong
constraints on origin. All existing observations are consistent with HVS
ejections from encounters with the massive black hole in the Galactic center.


title:
Majorana edge modes protected by emergent symmetry in a one dimensional
  fermi gas

abstract:
  We show that a one dimensional ultra-cold Fermi gas with Rashba-like spin
orbit coupling, a Zeeman field and intrinsic attractive interactions exhibits a
novel topological superfluid state, which forms in spite of total number
conservation and the absence of a single particle gap. Majorana zero modes are
localized to the interface between a topological region in the middle of the
trap and trivial regions at its wings. Unlike the realization of a topological
superconductor in proximity coupled nano-wires, the Majorana modes do not carry
a quantum number associated with the total fermion parity. Instead, the
topological degeneracy is protected by an emergent $Z_2$ symmetry present only
at low energies. We discuss the experimental implications of the novel zero
modes, as manifest for example in the response to modulation of a local
potential near the position of the Majorana bound states. For the range of
interaction strength corresponding to Luttinger parameter $1<K<2$ the zero
modes are unseperable from the gapless phonon continuum and therefore show up
as an algebraic zero bias resonance in the response. For $K>2$, on the other
hand the zero-mode can be detected as a sharp low frequency response at an
energy which generically scales with system size as $1/L^{K/2}$ and is
therefore parametrically separated from the phonons.


title:
Release of the Kraken: A Novel Money Multiplier Equation's Debut in 21st
  Century Banking

abstract:
  Historically, the banking multiplier has been in a range of 4 to 100, with
25% to 1% reserve ratios at most layers of the banking system encompassing the
majority of its range in recent centuries. Here it is shown that multipliers
over 1 000 can occur from a new mechanism in banking. This new multiplier uses
a default insurance note to insure an outstanding loan in order to return the
value of the insured amount into capital. The economic impact of this invention
is calculably greater than the original invention of reserve banking. The
consequence of this lending invention is to render the existing money
multiplier equations of reserve banking obsolete where it occurs. The equations
describing this new multiplier do not converge. Each set of parameters for
reserve percentage, nesting depth, etc. creates a unique logarithmic curve
rather than approaching a limit. Thus it is necessary to show the behavior of
this new equation by numerical methods. Understanding this new multiplier and
associated issues is necessary for economic analyses of the Global Financial
Crisis.


title:
Radiation Pressure on Submerged Mirrors: Implications for the Momentum
  of Light in Dielectric Media

abstract:
  Radiation pressure measurements on mirrors submerged in dielectric liquids
have consistently shown an effective Minkowski momentum for the photons within
the liquid. Using an exact theoretical calculation based on Maxwell's equations
and the Lorentz law of force, we demonstrate that this result is a consequence
of the fact that conventional mirrors impart, upon reflection, a 180 degree
phase-shift to the incident beam of light. If the mirror is designed to impart
a different phase, then the effective momentum will turn out to be anywhere
between the two extremes of the Minkowski and Abraham momenta. Since all values
in the range between these two extremes are equally likely to be found in
experiments, we argue that the photon momentum inside a dielectric host has the
arithmetic mean value of the Abraham and Minkowski momenta.


title:
A 33 year constancy of the X-ray coronae of AR Lac and eclipse diagnosis
  of scale height

abstract:
  Extensive X-ray and extreme ultraviolet (EUV) photometric observations of the
eclipsing RS CVn system AR Lac were obtained over the years 1997 to 2013 with
the Chandra X-ray Observatory Extreme Ultraviolet Explorer. During primary
eclipse, HRC count rates decrease by ~40%. A similar minimum is seen during one
primary eclipse observed by EUVE but not in others owing to intrinsic source
variability. Little evidence for secondary eclipses is present in either the
X-ray or EUV data, reminiscent of earlier X-ray and EUV observations. Primary
eclipses allow us to estimate the extent of a spherically symmetric corona on
the primary G star of about 1.3Rsun, or 0.86Rstar, and indicate the G star is
likely brighter than the K component by a factor of 2-5. Brightness changes not
attributable to eclipses appear to be dominated by stochastic variability and
are generally non-repeating. X-ray and EUV light curves cannot therefore be
reliably used to reconstruct the spatial distribution of emission assuming only
eclipses and rotational modulation are at work. Moderate flaring is observed,
where count rates increase by up to a factor of three above quiescence.
Combined with older ASCA, Einstein, EXOSAT, ROSAT and Beppo-SAX observations,
the data show that the level of quiescent coronal emission at X-ray wavelengths
has remained remarkably constant over 33 years, with no sign of variation due
to magnetic cycles. Variations in base level X-ray emission seen by Chandra
over 13 years are only ~10%, while variations back to pioneering Einstein
observations in 1980 amount to a maximum of 45% and more typically about 15%.


title:
Comment on "Linear wave dynamics explains observations attributed to
  dark-solitons in a polariton quantum fluid"

abstract:
  In a recent preprint (arXiv:1401.1128v1) Cilibrizzi and co-workers report
experiments and simulations showing the scattering of polaritons against a
localised obstacle in a semiconductor microcavity. The authors observe in the
linear excitation regime the formation of density and phase patterns
reminiscent of those expected in the non-linear regime from the nucleation of
dark solitons. Based on this observation, they conclude that previous
theoretical and experimental reports on dark solitons in a polariton system
should be revised. Here we comment why the results from Cilibrizzi et al. take
place in a very different regime than previous investigations on dark soliton
nucleation and do not reproduce all the signatures of its rich nonlinear
phenomenology. First of all, Cilibrizzi et al. consider a particular type of
radial excitation that strongly determines the observed patterns, while in
previous reports the excitation has a plane-wave profile. Most importantly, the
nonlinear relation between phase jump, soliton width and fluid velocity, and
the existence of a critical velocity with the time-dependent formation of
vortex-antivortex pairs are absent in the linear regime. In previous reports
about dark soliton and half-dark soliton nucleation in a polariton fluid, the
distinctive dark soliton physics is supported both by theory (analytical and
numerical) and experiments (both continuous wave and pulsed excitation).


title: A magnetic accretion switch in pre-cataclysmic binaries?

abstract:
  We have investigated the mass accretion rate implied by published surface
abundances of Si and C in the white dwarf component of the 3.62 hr period
pre-cataclysmic binary and planet host candidate QS Vir (DA+M2-4). Diffusion
timescales for gravitational settling imply $\dot{M} \sim 10^{-16}M_\odot$
yr$^{-1}$ for the 1999 epoch of the observations, which is three orders of
magnitude lower than measured from a 2006 {\it XMM-Newton} observation. This is
the first time that large accretion rate variations have been seen in a
detached pre-CV. A third body in a 14 yr eccentric orbit suggested in a recent
eclipse timing study is too distant to perturb the central binary sufficiently
to influence accretion. A hypothetical coronal mass ejection just prior to the
{\it XMM-Newton} observation might explain the higher accretion rate, but the
implied size and frequency of such events appear too great. We suggest
accretion is most likely modulated by a magnetic cycle on the secondary acting
as a wind "accretion switch", a mechanism that can be tested by X-ray and
ultraviolet monitoring. If so, QS Vir and similar pre-CVs could provide
powerful insights into hitherto inscrutable cataclysmic variable and M dwarf
magnetospheres, and mass and angular momentum loss rates.


title: Lifshitz Transitions in 122-Pnictides Under Pressure

abstract:
  We demonstrate, using $T=0$ first principles total energy calculations, that
observed pressure-driven anomalies in the entire 122-pnictides family
($A$Fe$_2$As$_2$; $A$ = alkali earth element Ca, Sr, Ba) can be understood as
consequences of Lifshitz transitions (LTs) \cite{Lifshitz60}. Our results for
energy band dispersions and spectra, lattice parameters, enthalpies, magnetism,
and elastic constants over a wide range of hydrostatic pressure provide a
coherent understanding of multiple transitions in these compounds, namely,
enthalpic, magnetic and tetragonal (T) - collapsed tetragonal (cT) transitions.
In particular, the T-cT transition and anomalies in lattice parameters and
elastic properties, observed at finite temperatures, are interpreted as arising
from proximity to $T=0$ Lifshitz transitions, wherein pressure causes
non-trivial changes in the Fermi surface topology in these materials.


title:
Open Quantum System Stochastic Dynamics and the Rotating Wave
  Approximation

abstract:
  We study the stochastic dynamics of a two-level quantum system interacting
with a stochastic magnetic field, and a single frequency electromagnetic field,
with and without making the rotating wave approximation (RWA). The
transformation to the rotating frame does not commute with the stochastic
Hamiltonian if the stochastic field has nonvanishing components in the
transverse direction. Hence, making the RWA modifies the stochastic terms in
the Hamiltonian. Modification of the decay terms is also required in a master
equation approach (i.e., the Liouville--von Neumann density matrix equation)
for describing the dynamics. For isotropic Gaussian white noise, the RWA
dynamics remains Markovian, although the Lindblad terms in the master equation
for the density matrix become time-dependent when the non-commutation of the
RWA transformation and the noise Hamiltonian is properly accounted for. We also
treat Ornstein--Uhlenbeck noise, and find, in contra-distinction to the white
noise case, a significant difference in the dynamics calculated with the RWA
when the non-commutation of the RWA transformation and the noise Hamiltonian is
taken into account. These findings are applicable to the modeling of any open
quantum system coupled to an electromagentic field.


title: Selection Rules for Hadronic Transitions of XYZ Mesons

abstract:
  Many of the XYZ mesons discovered in the last decade can be identified as
bound states of a heavy quark and antiquark in Born-Oppenheimer (B-O)
potentials defined by the energy of gluon and light-quark fields in the
presence of static color sources. The mesons include quarkonium hybrids, which
are bound states in excited flavor-singlet B-O potentials, and quarkonium
tetraquarks, which are bound states in flavor-nonsinglet B-O potentials. The
deepest hybrid potentials are known from lattice QCD calculations. The deepest
tetraquark potentials can be inferred from lattice QCD calculations of static
adjoint mesons. Selection rules for hadronic transitions are derived and used
to identify XYZ mesons that are candidates for ground-state energy levels in
the B-O potentials for charmonium hybrids and tetraquarks.


title: J/psi and Upsilon Polarization in Hadronic Production Processes

abstract:
  Both charm and bottom quarks form nonrelativistic bound states analogous to
positronium. The J/psi and psi(2S) charmonium states and the first three
Upsilon(nS) bottomonium states, all spin-triplet S-wave quarkonium states below
open-heavy-flavor thresholds, have relatively large branching ratios to e- e+
or mu- mu+ pairs. In hadron collisions, experiments measuring lepton pairs can
determine polarization by using angular correlation techniques. The
polarization, in turn, can be related theoretically to the production mechanism
for the bound state. This review summarizes experimental studies with proton
beams at fixed target and colliding beam accelerators, covering a
center-of-mass energy range from 39 to 7000 GeV for nucleon and antiproton
targets. Analyses using various polarization frames and spin-quantization axes
are described and results compared. A pattern emerges that connects
experimental results over the whole energy span. The theoretical implications
of the pattern are presented and a set of new measurements is proposed.


title:
Strong squeezing via phonon mediated spontaneous generation of photon
  pairs

abstract:
  We propose a scheme generating robust squeezed light by using double cavity
optomechanical system driven by a blue detuned laser in one cavity and by a red
detuned laser in the other. This double cavity system is shown to mimic
effectively an interaction that is similar to the one for the downconverter,
which is known to be a source of strong squeezing for the light fields. There
are however distinctions as the phonons, which lead to such an interaction, can
contribute to the quantum noise. We show that the squeezing of the output
fields in the order of $10$dB can be achieved even at the mirror temperature at
the order of $10$mK.