title:
Monte Carlo Study on Distortion of the Space-Dimension in COBE Monopole
  Data

abstract:
  A concise explanation of studies on distortion of space-time dimension is
briefly introduced. Second we obtain the limits (i.e., bounded values) of the
dimensionless chemical potential $\mu$, the Sunyaev--Zeldovich (SZ) effect y
and distortion of the space-dimension $\varepsilon$ by Monte Carlo (MC)
analysis of the parameter set (T, $d=3+\varepsilon$, $\mu$, and $y$) in cosmic
microwave data assuming that the SZ effect is positive (y>0). In this analysis,
the magnitude of the space-dimension d with distortion of the space-dimension
$\varepsilon$ is defined by $d=3+\varepsilon$. The limits of $\mu$ and $y$ are
determined as $|\mu| < 9\times 10^{-5} (2\sigma$) ($\mu = (-3.9\pm 2.6)\times
10^{-5} (\sigma$)), $|y| < 5\times 10^{-6} (2\sigma$) ($y = (2.0\pm 1.4)\times
10^{-6} (\sigma$)), while the distortion of the space-dimension is
$|\varepsilon| < 6\times 10^{-5} (2\sigma$) ($\varepsilon = (-0.78\pm
2.50)\times 10^{-5} (\sigma$)). The magnitudes of these three estimated limits
are ordered as $|\mu| \ge |\varepsilon| > |y|$. The estimated limit of $|y| <
5\times 10^{-6}$ appears to be related to re-ionization processes occurring at
redshift $z_{ri}\sim 10$. We also present data analysis assuming a relativistic
SZ effect.


title: Geometric Structure of Dimension Functions of Certain Continuous Fields

abstract:
  In this paper we study structural properties of the Cuntz semigroup and its
functionals for continuous fields of C*-algebras over finite dimensional
spaces. In a variety of cases, this leads to an answer to a conjecture posed by
Blackadar and Handelman. Enroute to our results, we determine when the stable
rank of continuous fields of C*-algebras over one dimensional spaces is one.


title:
Relation between exciton splittings, magnetic circular dichroism, and
  magnetization in wurtzite (Ga,Fe)N

abstract:
  The question of the correlation between magnetization, band splittings, and
magnetic circular dichroism (MCD) in the fundamental gap region of dilute
magnetic semiconductors is examined experimentally and theoretically taking the
case of wurtzite Ga(1-x)FexN as an example. Magnetization and
polarization-resolved reflectivity measurements have been performed down to 2K
and up to 7T for x = 0.2%. Optical transitions originating from all three free
excitons A, B and C, specific to the wurtzite structure, have been observed and
their evolution with the magnetic field determined. It is demonstrated that the
magnitude of the exciton splittings evaluated from reflectivity-MCD data can be
overestimated by more than a factor of 2, as compared to the values obtained by
describing the polarization-resolved reflectivity spectra with appropriate
dielectric functions. A series of model calculations shows that the
quantitative inaccuracy of MCD originates from a substantial influence of the
magnetization-dependent exchange interactions not only on the spin splittings
of excitons but also upon their linewidth and oscillator strength. At the same
time, a method is proposed that allows to evaluate the field and temperature
dependencies of the magnetization from MCD spectra. The accurate values of the
excitonic splittings and of the magnetization reported here substantiate the
magnitudes of the apparent $sp-d$ exchange integrals in (Ga,Fe)N previously
determined.


title:
Influence of ripening and creaming on the aggregation rate of
  dodecane-in-water nanoemulsions. Is the creaming rate an appropriate measure
  of emulsion stability?

abstract:
  The behavior of four oil-in-water (O/W) ioinic nanoemulsions composed of
dodecane, and mixtures of dodecane with squalene and tetra-chloro-ethylene is
studied. These nanoemulsions were stabilized with sodium dodecyl sulfate (SDS).
The behavior of the turbidity and the average radius of the emulsions were
followed as a function of time. The results illustrate the shortcomings of
characterizing the stability of emulsions by their creaming rate.


title: Integrality and Gauge Dependence of Hennings TQFTs

abstract:
  We provide a general construction of integral TQFTs over a general
commutative ring, $\mathbf{k}$, starting from a finite Hopf algebra over
$\mathbf{k}$ which is Frobenius and double balanced. These TQFTs specialize to
the Hennings invariants of the respective doubles on closed 3-manifolds.
  We show the construction applies to index 2 extensions of the Borel parts of
Lusztig's small quantum groups for all simple Lie types, yielding integral
TQFTs over the cyclotoic integers for surfaces with boundary.
  We further establish and compute isomorphisms of TQFT functors constructed
from Hopf algebras that are related by a strict gauge transformation in the
sense of Drinfeld. Formulas for the natural isomorphisms are given in terms of
the gauge twist element.
  These results are combined and applied to show that the Hennings invariant
associated to quantum-$sl_2$ takes values in the cyclotomic integers. Using
prior results of Chen et al we infer integrality also of the
Witten-Reshetikhin-Turaev $SO(3)$ invariant for rational homology spheres.
  As opposed to most other approaches the methods described in this article do
not invoke calculations of skeins, knots polynomials, or representation theory,
but follow a combinatorial construction that uses only the elements and
operations of the underlying Hopf algebras.


title:
A Quantitative Regularity Estimate for Nonnegative Supersolutions of
  Fully Nonlinear Uniformly Parabolic Equations

abstract:
  This note establishes an interior quantitative lower bound for nonnegative
supersolutions of fully nonlinear uniformly parabolic equations. The result may
be interpreted as a nonlinear, quantitative version of a growth lemma
established by Krylov and Safonov for nonnegative supersolutions of linear
uniformly parabolic equations in nondivergence form. Our approach is different,
and follows from an application of the Fabes-Stroock estimate. The result is
the parabolic analogue of an elliptic regularity estimate established by
Caffarelli, Souganidis, and Wang in the stochastic homogenization of fully
nonlinear uniformly elliptic equations.


title: Quantum Anomalous Hall Effect with Higher Plateaus

abstract:
  Quantum anomalous Hall (QAH) effect in magnetic topological insulators is
driven by the combination of spontaneous magnetic moments and spin-orbit
coupling. Its recent experimental discovery raises the question if higher
plateaus can also be realized. Here we present a general theory for QAH effect
with higher Chern numbers, and show by first-principles calculations that thin
film magnetic topological insulator of Cr-doped Bi$_2$(Se,Te)$_3$ is a
candidate for the C=2 QAH insulator. Remarkably, whereas higher magnetic field
leads to lower Hall conductance plateaus in the integer quantum Hall effect,
higher magnetic moment leads to higher Hall conductance plateaus in the QAH
effect.


title: Model companion of ordered theories with an automorphism

abstract:
  Kikyo and Shelah showed that if $T$ is a theory with the Strict Order
Property in some first-order language $\mathcal{L}$, then in the expanded
language $\mathcal{L}_\sigma := \mathcal{L}\cup\{\sigma\}$ with a new unary
function symbol $\sigma$, the bigger theory $T_\sigma := T\cup\{``\sigma
\mbox{is an} \mathcal{L}\mbox{-automorphism''}\}$ does not have a model
companion. We show in this paper that if, however, we restrict the automorphism
and consider the theory $T_\sigma$ as the base theory $T$ together with a
``restricted'' class of automorphisms, then $T_\sigma$ can have a model
companion in $\mathcal{L}_\sigma$. We show this in the context of linear orders
and ordered abelian groups.


title: Desingularizations of quiver Grassmannians via graded quiver varieties

abstract:
  Inspired by recent work of Cerulli-Feigin-Reineke on desingularizations of
quiver Grassmannians of representations of Dynkin quivers, we obtain
desingularizations in considerably more general situations and in particular
for Grassmannians of modules over iterated tilted algebras of Dynkin type. Our
desingularization map is constructed from Nakajima's desingularization map for
graded quiver varieties.


title:
Evidence for Fluctuating Charge Stripes far above the Charge-Ordering
  Transition in La$_{1.67}$ Sr$_{0.33}$ NiO$_{4}$

abstract:
  The temperature evolution of structural effects associated with charge (CO)
and spin order (SO) in La$_{1.67}$Sr$_{0.33}$NiO$_{4}$ has been investigated
using neutron powder diffraction. We report an anomalous shrinking of the $c/a$
lattice parameter ratio that correlates with $T_{\rm CO}$. The sign of this
change can be explained by the change in interlayer Coulomb energy between the
static stripe-ordered state and the fluctuating stripe-ordered state or the
charge-disordered state. In addition, we identify a contribution to the
mean-square displacements of Ni and in-plane O atoms whose width correlates
quite well with the size of the pseudogap extracted from the reported optical
conductivity, with a non-Debye-like component that persists below and well
above $T_{\rm CO}$. We infer that dynamic charge-stripe correlations survive to
$T\sim2T_{\rm CO}$


title: Continuity of the Lyapunov exponents for quasiperiodic cocycles

abstract:
  Consider the Banach manifold of real analytic linear cocycles with values in
the general linear group of any dimension and base dynamics given by a
Diophantine translation on the circle. We prove a precise higher dimensional
Avalanche Principle and use it in an inductive scheme to show that the Lyapunov
spectrum blocks associated to a gap pattern in the Lyapunov spectrum of such a
cocycle are locally Holder continuous. Moreover, we show that all Lyapunov
exponents are continuous everywhere in this Banach manifold, irrespective of
any gap pattern in their spectra. These results also hold for Diophantine
translations on higher dimensional tori, albeit with a loss in the modulus of
continuity of the Lyapunov spectrum blocks.


title:
How hydrophobic drying forces impact the kinetics of molecular
  recognition

abstract:
  A model of protein-ligand binding kinetics in which slow solvent dynamics
results from hydrophobic drying transitions is investigated. Molecular dynamics
simulations show that solvent in the receptor pocket can fluctuate between wet
and dry states with lifetimes in each state that are long enough for the
extraction of a separable potential of mean force and wet-to-dry transitions.
We introduce a Diffusive Surface Hopping Model that is represented by a
two-dimensional Markovian master equation. One dimension is the standard
reaction coordinate, the ligand-pocket separation, and the other is the solvent
state in the region between ligand and binding pocket which specifies whether
it is wet or dry. In our model, the ligand diffuses on a dynamic free energy
surface which undergoes kinetic transitions between the wet and dry states. The
model yields good agreement with results from explicit solvent molecular
dynamics simulation and an improved description of the kinetics of hydrophobic
assembly. Furthermore, it is consistent with a "non-Markovian Brownian theory"
for the ligand-pocket separation coordinate alone.


title: Enhanced hyperfine-induced spin dephasing in a magnetic-field gradient

abstract:
  Magnetic-field gradients are important for single-site addressability and
electric-dipole spin resonance of spin qubits in semiconductor devices. We show
that these advantages are offset by a potential reduction in coherence time due
to the non-uniformity of the magnetic field experienced by a nuclear-spin bath
interacting with the spin qubit. We theoretically study spins confined to
quantum dots or at single donor impurities, considering both free-induction and
spin-echo decay. For quantum dots in GaAs, we find that, in a realistic
setting, a magnetic-field gradient can reduce the Hahn-echo coherence time by
almost an order of magnitude. This problem can, however, be resolved by
applying a moderate external magnetic field to enter a motional averaging
regime. For quantum dots in silicon, we predict a cross-over from non-Markovian
to Markovian behavior that is unique to these devices. Finally, for very small
systems such as single phosphorus donors in silicon, we predict a breakdown of
the common Gaussian approximation due to finite-size effects.


title: Control of the Exciton Transfer in Quantum Dots by the Stark Effect

abstract:
  Resonant transfer of energy between excited states in a system of two
semiconductor quantum dots is studied theoretically. The model Hamiltonian has
been formulated, which allowed describe the impact on the dynamics of the
resonant laser pulse, the Coulomb interaction, the static Stark effect, and the
relaxation of the exciton states. Examples of calculations for efficiency of
the energy transfer under different excitation conditions are presented. The
control of the process by the level shift in a constant electric field is
demonstrated.


title:
Possible scenarios for eccentricity evolution in the extrasolar
  planetary system HD 181433

abstract:
  We analyse the dynamics of the multiple planet system HD 181433. This
consists of two gas giant planets (c and d) with msin i = 0.65 MJup and 0.53
MJup orbiting with periods 975 and 2468 days, respectively. The two planets
appear to be in a 5:2 mean motion resonance, as this is required for the system
to be dynamically stable. A third planet with mass m_b sin i = 0.023 MJup
orbits close to the star with orbital period 9.37 days. Each planet orbit is
significantly eccentric, with current values estimated to be e_b = 0.39, e_c =
0.27 and e_d = 0.47. In this paper we assess different scenarios that may
explain the origin of these eccentric orbits, with particular focus on the
innermost body, noting that the large eccentricity of planet b cannot be
explained through secular interaction with the outer pair. We consider a
scenario in which the system previously contained an additional giant planet
that was ejected during a period of dynamical instability among the planets.
N-body simulations are presented that demonstrate that during scattering and
ejection among the outer planets a close encounter between a giant and the
inner body can raise e_b to its observed value. We consider the possibility
that an undetected planet in the system increases the secular forcing of planet
b by the exterior giant planets, but we find that the resulting eccentricity is
not large enough to agree with the observed one. We also consider a scenario in
which the spin-down of the central star causes the system to pass through
secular resonance. Spin-down rates below the critical value lead to longterm
capture of planet b in secular resonance, driving the eccentricity toward
unity. If additional short-period low mass planets are present in the system,
however, we find that mutual scattering can release planet b from the secular
resonance, leading to a system with orbital parameters similar to those
observed today.


title:
On a local mass dimension one Fermi field of spin one-half and the
  theoretical crevice that allows it

abstract:
  Since the 1928 seminal work of Dirac, and its subsequent development by
Weinberg, a view is held that there is a unique Fermi field of spin one-half.
It is endowed with mass dimension three-half. Combined, these characteristics
profoundly affect the phenomenology of the high energy physics, astrophysics,
and cosmology. We here present a counter example by providing a local, mass
dimension one, Fermi field of spin one-half. The theory, inter alia, thus
allows dimensionless quartic self interaction for the new fermions, and its
only other dimensionless coupling is quadratic in the new fermions and in the
standard-model scalar field. For these reasons, the immediate application of
the new theory resides in the dark-matter sector of physical reality. The
lowest-mass associated new particle may leave its unique signature at the Large
Hadron Collider. We discuss in detail the theoretical crevice that allows the
existence of the new quantum field.

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


title: Inequalities for the one-dimensional analogous of the Coulomb potential

abstract:
  In this paper our aim is to present some monotonicity and convexity
properties for the one dimensional regularization of the Coulomb potential,
which has applications in the study of atoms in magnetic fields and which is in
fact a particular case of the Tricomi confluent hypergeometric function.
Moreover, we present some Tur\'an type inequalities for the function in the
question and we deduce from these inequalities some new tight upper bounds for
the Mills ratio of the standard normal distribution.


title:
The Monge-Amp\`ere equation for (n-1)-plurisubharmonic functions on a
  compact K\"ahler manifold

abstract:
  A C^2 function on C^n is called (n-1)-plurisubharmonic in the sense of
Harvey-Lawson if the sum of any n-1 eigenvalues of its complex Hessian is
nonnegative. We show that the associated Monge-Ampere equation can be solved on
any compact Kahler manifold. As a consequence we prove the existence of
solutions to an equation of Fu-Wang-Wu, giving Calabi-Yau theorems for
balanced, Gauduchon and strongly Gauduchon metrics on compact Kahler manifolds.


title: On Exotic Lagrangian Tori in CP^2

abstract:
  We construct an exotic monotone Lagrangian torus in CP^2 using techniques
motivated by mirror symmetry. We show that it bounds 10 families of Maslov
index 2 holomorphic discs, and it follows that this exotic torus is not
Hamiltonian isotopic to the known Clifford and Chekanov tori.


title: From eV to EeV: Neutrino Cross Sections Across Energy Scales

abstract:
  Since its original postulation by Wolfgang Pauli in 1930, the neutrino has
played a prominent role in our understanding of nuclear and particle physics.
In the intervening 80 years, scientists have detected and measured neutrinos
from a variety of sources, both man-made and natural. Underlying all of these
observations, and any inferences we may have made from them, is an
understanding of how neutrinos interact with matter. Knowledge of neutrino
interaction cross sections is an important and necessary ingredient in any
neutrino measurement. With the advent of new precision experiments, the demands
on our understanding of neutrino interactions is becoming even greater. The
purpose of this article is to survey our current knowledge of neutrino cross
sections across all known energy scales: from the very lowest energies to the
highest that we hope to observe. The article covers a wide range of neutrino
interactions including coherent scattering, neutrino capture, inverse beta
decay, low energy nuclear interactions, quasi-elastic scattering, resonant pion
production, kaon production, deep inelastic scattering and ultra-high energy
interactions. Strong emphasis is placed on experimental data whenever such
measurements are available.


title: Studying new classes of graph metrics

abstract:
  In data analysis, there is a strong demand for graph metrics that differ from
the classical shortest path and resistance distances. Recently, several new
classes of graph metrics have been proposed. This paper presents some of them
featuring the cutpoint additive distances. These include the path distances,
the reliability distance, the walk distances, and the logarithmic forest
distances among others. We discuss a number of connections between these and
other distances.


title: A test of unification towards the radio source PKS1413+135

abstract:
  We point out that existing astrophysical measurements of combinations of the
fine-structure constant $\alpha$, the proton-to-electron mass ratio $\mu$ and
the proton gyromagnetic ratio $g_p$ towards the radio source PKS1413+135 can be
used to individually constrain each of these fundamental couplings. While the
accuracy of the available measurements is not yet sufficient to test the
spatial dipole scenario, our analysis serves as a proof of concept as new
observational facilities will soon allow significantly more robust tests.
Moreover, these measurements can also be used to obtain constraints on certain
classes of unification scenarios, and we compare the constraints obtained for
PKS1413+135 with those previously obtained from local atomic clock
measurements.


title:
Connection between GRW "spontaneous collapse" and Mensky's "restricted
  path integral" models

abstract:
  In this paper we will show how Mensky's model of "restricted path integrals"
can be derived from GRW "spontaneous collapse" model.


title:
Effects of Electromagnetic Field on the Dynamical Instability of
  Expansionfree Gravitational Collapse

abstract:
  In this paper, we discuss the effects of electromagnetic field on the
dynamical instability of a spherically symmetric expansionfree gravitational
collapse. Darmois junction conditions are formulated by matching interior
spherically symmetric spacetime to exterior Reissner-Nordstr$\ddot{o}$m
spacetime. We investigate the role of different terms in the dynamical equation
at Newtonian and post Newtonian regimes by using perturbation scheme. It is
concluded that instability range depends upon pressure anisotropy, radial
profile of energy density and electromagnetic field, but not on the adiabatic
index $\Gamma$. In particular, the electromagnetic field reduces the unstable
region.


title:
Special Polynomial Rings, Quasi Modular Forms and Duality of Topological
  Strings

abstract:
  We study the differential polynomial rings which are defined using the
special geometry of the moduli spaces of Calabi-Yau threefolds. The higher
genus topological string amplitudes are expressed as polynomials in the
generators of these rings, giving them a global description in the moduli
space. At particular loci, the amplitudes yield the generating functions of
Gromov-Witten invariants. We show that these rings are isomorphic to the rings
of quasi modular forms for threefolds with duality groups for which these are
known. For the other cases, they provide generalizations thereof. We
furthermore study an involution which acts on the quasi modular forms. We
interpret it as a duality which exchanges two distinguished expansion loci of
the topological string amplitudes in the moduli space. We construct these
special polynomial rings and match them with known quasi modular forms for
non-compact Calabi-Yau geometries and their mirrors including local P^2 and
local del Pezzo geometries with E_5,E_6,E_7 and E_8 type singularities. We
provide the analogous special polynomial ring for the quintic.


title: D-brane Bremsstrahlung

abstract:
  We study the dynamics of ultrarelativistic D-branes. The dominant phenomenon
is bremsstrahlung: mild acceleration induced by closed string interactions
triggers extremely rapid energy loss through radiation of massless closed
strings. After characterizing bremsstrahlung from a general k-dimensional
extended object in a D-dimensional spacetime, we incorporate effects specific
to D-branes, including velocity-dependent forces and open string pair creation.
We then show that dissipation due to bremsstrahlung can substantially alter the
dynamics in DBI inflation.


title:
Bimetric gravity doubly coupled to matter: theory and cosmological
  implications

abstract:
  A ghost-free theory of gravity with two dynamical metrics both coupled to
matter is shown to be consistent and viable. Its cosmological implications are
studied, and the models, in particular in the context of partially massless
gravity, are found to explain the cosmic acceleration without resorting to dark
energy.


title:
Estimating the large-scale angular power spectrum in the presence of
  systematics: a case study of Sloan Digital Sky Survey quasars

abstract:
  The angular power spectrum is a powerful statistic for analysing cosmological
signals imprinted in the clustering of matter. However, current galaxy and
quasar surveys cover limited portions of the sky, and are contaminated by
systematics that can mimic cosmological signatures and jeopardise the
interpretation of the measured power spectra. We provide a framework for
obtaining unbiased estimates of the angular power spectra of large-scale
structure surveys at the largest scales using quadratic estimators. The method
is tested by analysing the 600 CMASS mock catalogues constructed by Manera et
al. (2013) for the Baryon Oscillation Spectroscopic Survey (BOSS). We then
consider the Richards et al. (2009) catalogue of photometric quasars from the
Sixth Data Release (DR6) of the Sloan Digital Sky Survey (SDSS), which is known
to include significant stellar contamination and systematic uncertainties.
Focusing on the sample of ultraviolet-excess (UVX) sources, we show that the
excess clustering power present on the largest-scales can be largely mitigated
by making use of improved sky masks and projecting out the modes corresponding
to the principal systematics. In particular, we find that the sample of objects
with photometric redshift $1.3 < z_p < 2.2$ exhibits no evidence of
contamination when using our most conservative mask and mode projection. This
indicates that any residual systematics are well within the statistical
uncertainties. We conclude that, using our approach, this sample can be used
for cosmological studies.


title: Robust determination of the scalar boson couplings

abstract:
  We study the indirect effects of new physics on the phenomenology of the
"Higgs-like" particle. Assuming that the recently observed state belongs to a
light electroweak doublet scalar and that the SU(2)_L x U(1)_Y symmetry is
linearly realized, we parametrize these effects in terms of an effective
Lagrangian at the electroweak scale. We choose the dimension--six operator
basis which allows us to make better use of all the available data to constrain
the coefficients of the dimension-six operators. We perform a global
6--parameter fit which allows simultaneous determination of the standard model
scalar couplings to gluons, electroweak gauge bosons, bottom quarks, and tau
leptons. The results are based on the data released at Moriond 2013. Moreover,
our formalism leads to strong constraints on the electroweak triple gauge boson
couplings. Note added: The analysis has been updated with a NEW GLOBAL
6-PARAMETER FIT with all the public data available after Moriond 2013. Updates
of this analysis are provided at the website http://hep.if.usp.br/Higgs, as
well as new versions of the manuscript.


title:
Natal Kicks of Stellar-Mass Black Holes by Asymmetric Mass Ejection in
  Fallback Supernovae

abstract:
  Integrating trajectories of low-mass X-ray binaries containing black holes
within the Galactic potential, Repetto, Davies & Sigurdsson recently showed
that the large distances of some systems above the Galactic plane can only be
explained if black holes receive appreciable natal kicks. Surprisingly, they
found that the distribution of black hole kick velocities (rather than that of
the momenta) should be similar to that of neutron stars. Here I argue that this
result can be understood if neutron star and black hole kicks are a consequence
of large-scale asymmetries created in the supernova ejecta by the explosion
mechanism. The corresponding anisotropic gravitational attraction of the
asymmetrically expelled matter does not only accelerate new-born neutron stars
by the "gravitational tug-boat mechanism". It can also lead to delayed
black-hole formation by asymmetric fallback of the slowest parts of the initial
ejecta onto the transiently existing neutron star, in course of which the
momentum of the black hole can grow with the fallback mass. Black hole kick
velocities will therefore not be reduced by the ratio of neutron star to black
hole mass as would be expected for kicks caused by anisotropic neutrino
emission of the nascent neutron star.


title: Dust, Gas, and Metallicities of Cosmologically Distant Lens Galaxies

abstract:
  We homogeneously analyzed the \chandra\ X-ray observations of 10
gravitational lenses, HE 0047-1756, QJ 0158-4325, SDSS 0246-0805, HE 0435-1223,
SDSS 0924+0219, SDSS 1004+4112, HE 1104-1805, PG 1115+080, Q 1355-2257, and Q
2237+0305, to measure the differential X-ray absorption between images, the
metallicity, and the dust-to-gas ratio of the lens galaxies. We detected
differential absorption in all lenses except SDSS 0924+0219 and HE 1104-1805.
This doubles the sample of dust-to-gas ratio measurements in cosmologically
distant lens galaxies. We successfully measured the gas phase metallicity of
three lenses, Q 2237+0305, SDSS 1004+4112, and B 1152+199 from the X-ray
spectra. Our results suggest a linear correlation between metallicity and
dust-to-gas ratio (i.e., a constant metal-to-dust ratio), consistent with what
is found for nearby galaxies. We obtain an average dust-to-gas ratio
$E(B-V)/N_H=1.17^{+0.41}_{-0.31} \times 10^{-22}\rm mag\,cm^2\,atom^{-1}$ in
the lens galaxies, with an intrinsic scatter of $\rm0.3\,dex$. Combining these
results with data from GRB afterglows and quasar foreground absorbers, we found
a mean dust-to-gas ratio $\mdtg,$ now significantly lower than the average
Galactic value, $1.7\,\times 10^{-22}\,\rm mag\, cm^{2}\, atoms^{-1}.$ This
suggests evolution of dust-to-gas ratios with redshift and lower average
metallicities for the higher redshift galaxies, consistent with current metal
and dust evolution models of interstellar medium. The slow evolution in the
metal-to-dust ratio with redshift implies very rapid dust formation in high
redshift ($z>2$) galaxies.


title: Focusing on Warm Dark Matter with Lensed High-redshift Galaxies

abstract:
  We propose a novel use of high-redshift galaxies, discovered in deep Hubble
Space Telescope (HST) fields around strong lensing clusters. These fields probe
small comoving volumes (about 1000 cubic Mpc) at high magnification ({\mu} >
10), and can detect otherwise inaccessible ultra-faint galaxies. Even a few
galaxies found in such small volumes require a very high number density of
collapsed dark matter (DM) halos. This implies significant primordial power on
small scales, allowing these observations to rule out popular alternatives to
standard cold dark matter (CDM) models, such as warm dark matter (WDM). In this
work, we analytically compute WDM halo mass functions at z = 10, including the
effects of both particle free-streaming and residual velocity dispersion. The
preliminary number density corresponding to the two galaxies at z about 10
already detected by the Cluster Lensing And Supernova survey with Hubble
(CLASH) constrains the WDM particle mass to m_x > 1 (0.9) keV at 84% (99.9%)
confidence limit (for a thermal relic relativistic at decoupling). This limit
depends only on the WDM halo mass function and, unlike previous constraints on
m_x, is independent of any astrophysical modeling. The forthcoming HST Frontier
Fields can significantly tighten these constraints.


title:
A Two-moment Radiation Hydrodynamics Module in Athena Using a
  Time-explicit Godunov Method

abstract:
  We describe a module for the Athena code that solves the gray equations of
radiation hydrodynamics (RHD), based on the first two moments of the radiative
transfer equation. We use a combination of explicit Godunov methods to advance
the gas and radiation variables including the non-stiff source terms, and a
local implicit method to integrate the stiff source terms. We adopt the M1
closure relation and include all leading source terms. We employ the reduced
speed of light approximation (RSLA) with subcycling of the radiation variables
in order to reduce computational costs. Our code is dimensionally unsplit in
one, two, and three space dimensions and is parallelized using MPI. The
streaming and diffusion limits are well-described by the M1 closure model, and
our implementation shows excellent behavior for a problem with a concentrated
radiation source containing both regimes simultaneously. Our operator-split
method is ideally suited for problems with a slowly varying radiation field and
dynamical gas flows, in which the effect of the RSLA is minimal. We present an
analysis of the dispersion relation of RHD linear waves highlighting the
conditions of applicability for the RSLA. To demonstrate the accuracy of our
method, we utilize a suite of radiation and RHD tests covering a broad range of
regimes, including RHD waves, shocks, and equilibria, which show second-order
convergence in most cases. As an application, we investigate radiation-driven
ejection of a dusty, optically thick shell in the interstellar medium (ISM).
Finally, we compare the timing of our method with other well-known iterative
schemes for the RHD equations. Our code implementation, Hyperion, is suitable
for a wide variety of astrophysical applications and will be made freely
available on the Web.


title: On the Form of the Spitzer Leavitt Law and its Dependence on Metallicity

abstract:
  The form and metallicity-dependence of Spitzer mid-infrared Cepheid relations
are a source of debate. Consequently, Spitzer 3.6 and 4.5 um period-magnitude
and period-color diagrams were re-examined via robust routines, thus providing
the reader an alternative interpretation to consider. The relations (nearly
mean-magnitude) appear non-linear over an extensive baseline (0.45< logPo
<2.0), particularly the period-color trend, which to first-order follows
constant (3.6-4.5) color for shorter-period Cepheids and may transition into a
bluer convex trough at longer-periods. The period-magnitude functions can be
described by polynomials (e.g., [3.6 um]=Ko-(3.071+-0.059)
logPo-(0.120+-0.032)logPo^2), and Cepheid distances computed using 3.6 and 4.5
um relations agree and the latter provides a first-order consistency check (CO
sampled at 4.5 um does not seriously compromise those distances). The
period-magnitude relations appear relatively insensitive to metallicity
variations ([Fe/H]~0 to -0.75), a conclusion inferred partly from comparing
galaxy distances established from those relations and NED-D (n>700), yet a
solid conclusion awaits comprehensive mid-infrared observations for metal-poor
Cepheids in IC 1613 ([Fe/H] -1). The Cepheid-based distances were corrected for
dust obscuration using a new ratio (i.e., A(3.6)/E(B-V)=0.18+-0.06) deduced
from GLIMPSE (Spitzer) data.


title:
Cosmology or Catastrophe? A non-minimally coupled scalar in an
  inhomogeneous universe

abstract:
  A non-minimally coupled scalar field can have, in principle, a negative
effective Planck mass squared which depends on the scalar field. Surprisingly,
an isotropic and homogeneous cosmological universe with a non-minimally coupled
scalar field is perfectly smooth as the rolling scalar field causes the
effective Planck mass to change sign and pass through zero. However, we show
that any small deviations from homogeneity diverge as the effective Planck mass
vanishes, with catastrophic consequences for the cosmology. The physical origin
of the divergence is due to the presence of non-zero scalar anisotropic stress
from the non-minimally coupled scalar field. Thus, while the homogeneous and
isotropic cosmology appears surprisingly sensible when the effective Planck
mass vanishes, inhomogeneities tell a different story.


title: How to switch on and off a Gamma-ray burst through a magnetar

abstract:
  One of the most elusive features of Gamma Ray Bursts (GRBs) is the sporadic
emission prior to the main prompt event observed in at least $\sim 15\%$ of
cases. These precursors have spectral and temporal properties similar to the
main prompt emission, and smaller, but comparable, energetics. They are
separated from the main event by a quiescent time that may be extremely long
and, in some cases, more than one precursor has been observed in the same
burst. Precursors are still a puzzle: despite many attempts none of the
proposed models can account for all the observed features. Based on the
complete sample of bright long GRBs observed by Swift (BAT6), we propose a new
scenario for which precursors are explained by assuming that the central GRB
engine is a newly born magnetar. In this model the precursor and the prompt
emission arise from accretion of matter onto the surface of the magnetar. The
accretion process can be halted by the centrifugal drag exerted by the rotating
magnetosphere onto the in-falling matter, allowing for multiple precursors and
very long quiescent times.


title: W Symmetry and Integrability of Higher spin black holes

abstract:
  We obtain the asymptotic symmetry algebra of sl(3,R) x sl(3,R) Chern-Simons
theory with Dirichlet boundary conditions for fixed chemical potential. These
boundary conditions are obeyed by higher spin black holes. For each embedding
of sl(2,R) into sl(3,R), we show that the asymptotic symmetry group is
independent of the chemical potential. On the one hand, starting from AdS3 in
the principal embedding, we show that the W3 x W3 symmetry is preserved upon
turning on perturbatively spin 3 chemical potentials. On the other hand,
starting from AdS3 in the diagonal embedding, we show that the W3^(2) x W3^(2)
symmetry is preserved upon turning on finite spin 3/2 chemical potentials. We
also make connections between the canonical Lagrangian formalism and
integrability methods based on the third KdV (Boussinesq) hierarchy.


title: Weak lensing detection of intra-cluster filaments with ground based data

abstract:
  According to the current standard model of Cosmology, matter in the Universe
arranges itself along a network of filamentary structure. These filaments
connect the main nodes of this so-called 'Cosmic Web', which are clusters of
galaxies. Although its large-scale distribution is clearly characterized by
numerical simulations, constraining the dark matter content of the cosmic web
in reality turns out to be difficult. The natural method of choice is
gravitational lensing. However, the direct detection and mapping of the elusive
filament signal is challenging and in this work we present two
methods,specifically tailored to achieve this task. A linear matched filter
aims at the detection of the smooth mass component of filaments and is
optimized to perform a shear decomposition that follows the anisotropic
component of the lensing signal. Filaments clearly inherit this property due to
their morphology. At the same time, the contamination arising from the central
massive cluster is controlled in a natural way. The filament 1 {\sigma}
detection is of about {\kappa} ~ 0.01-0.005 according to the filter's template
width and length, enabling the detection of structures out of reach with other
approaches. The second, complementary method seeks to detect the clumpy
component of filaments. The detection is determined by the number density of
sub-clump identifications in an area enclosing the potential filament, as it
was found within the observed field with the filter approach. We test both
methods against Mock observations based on realistic N-Body simulations of
filamentary structure and prove the feasibility of detecting filaments with
ground-based data.


title: Angular momentum evolution in laser-plasma accelerators

abstract:
  The transverse properties of an electron beam are characterized by two
quantities, the emittance which indicates the electron beam extend in the phase
space and the angular momentum which allows for non-planar electron
trajectories. Whereas the emittance of electron beams produced in laser- plasma
accelerator has been measured in several experiments, their angular momentum
has been scarcely studied. It was demonstrated that electrons in laser-plasma
accelerator carry some angular momentum, but its origin was not established.
Here we identify one source of angular momentum growth and we present
experimental results showing that the angular momentum content evolves during
the acceleration.


title: Supersymmetric AdS Black Rings

abstract:
  It has been proven in arXiv:1303.0853 that all regular supersymmetric
near-horizon geometries in minimal five-dimensional gauged supergravity admit
automatic supersymmetry enhancement. Using this result, the integrability
conditions associated with the existence of the additional supersymmetry are
analysed, and the near-horizon geometries are determined explicitly. We show
that they all correspond to previously constructed examples. Hence, there are
no supersymmetric black ring solutions in minimal five-dimensional gauged
supergravity.


title: An Open Question on the Uniqueness of (Encrypted) Arithmetic

abstract:
  We ask whether two or more images of arithmetic may inhabit the same space
via different encodings. The answers have significance for a class of processor
design that does all its computation in an encrypted form, without ever
performing any decryption or encryption itself. Against the possibility of
algebraic attacks against the arithmetic in a `crypto-processor' (KPU) we
propose a defence called `ABC encryption' and show how this kind of encryption
makes it impossible for observations of the arithmetic to be used by an
attacker to discover the actual values. We also show how to construct such
encrypted arithmetics.


title: Recursive Sorting in Lattices

abstract:
  The direct application of the definition of sorting in lattices is
impractical because it leads to an algorithm with exponential complexity. In
this paper we present for distributive lattices a recursive formulation to
compute the sort of a sequence. This alternative formulation is inspired by the
identity that underlies Pascal's triangle. It provides quadratic complexity and
is in fact a generalization of insertion sort for lattices.


title:
On the definiteness of associated energy-momentum tensors to a class of
  general variation problems

abstract:
  We show the point-wise definiteness and some other properties of the
energy-momentum tensor for a certain class of Euler-Lagrange equations under
quite general conditions.


title: Glassy behavior of two-dimensional stripe-forming systems

abstract:
  We study two dimensional frustrated but non-disordered systems applying a
replica approach to a stripe forming model with competing interactions. The
phenomenology of the model is representative of several well known systems,
like high-Tc superconductors and ultrathin ferromagnetic films, which have been
the subject of intense research. We establish the existence of a glass
transition to a non-ergodic regime accompanied by an exponential number of long
lived metastable states, responsible for slow dynamics and non-equilibrium
effects.


title: The B_s --> mu+mu- and B_d --> mu+mu- Decays: Standard Model and Beyond

abstract:
  I review the status of the rare decays B_s --> mu+mu- and B_d --> mu+mu-. The
latest Standard Model predictions for the corresponding branching ratios are
discussed. An overview of additional observables that are accessible in the B_s
--> mu+mu- decay is given. The new physics implications of the recent
measurement of the B_s --> mu+mu- branching ratio are discussed both model
independently and in the context of the Minimal Supersymmetric Standard Model.


title:
Searches for the Higgs boson decaying to W^{+} W^{-} -> l^{+}nu
  l^{-}nubar with the CDF II detector

abstract:
  We present a search for a standard model Higgs boson decaying to two $W$
bosons that decay to leptons using the full data set collected with the CDF II
detector in $\sqrt{s}=1.96$ TeV $p\bar{p}$ collisions at the Fermilab Tevatron,
corresponding to an integrated luminosity of 9.7 fb${}^{-1}$. We obtain no
evidence for production of a standard model Higgs boson with mass between 110
and 200 GeV/$c^2$, and place upper limits on the production cross section
within this range. We exclude standard model Higgs boson production at the 95%
confidence level in the mass range between 149 and 172 GeV/$c^2$, while
expecting to exclude, in the absence of signal, the range between 155 and 175
GeV/$c^2$. We also interpret the search in terms of standard model Higgs boson
production in the presence of a fourth generation of fermions and within the
context of a fermiophobic Higgs boson model. For the specific case of a
standard model-like Higgs boson in the presence of fourth-generation fermions,
we exclude at the 95% confidence level Higgs boson production in the mass range
between 124 and 200 GeV/$c^2$, while expecting to exclude, in the absence of
signal, the range between 124 and 221 GeV/$c^2$.


title:
Calibrated Fair Measures of Measure: Indices to Quantify an Individual's
  Scientific Research Output

abstract:
  Are existing ways of measuring scientific quality reflecting disadvantages of
not being part of giant collaborations? How could possible discrimination be
avoided? We propose indices defined for each discipline (subfield) and which
count the plausible contributions added up by collaborators maintaining the
spirit of interdependency. Based on the growing debate about defining potential
biases and detecting unethical behavior, a standardized method to measure
contributions of the astronomical number of coauthors is introduced.


title:
Genetic Complexity in a Drosophila Model of Diabetes-Associated
  Misfolded Human Proinsulin

abstract:
  Here we use Drosophila melanogaster to create a genetic model of human
permanent neonatal diabetes mellitus and present experimental results
describing dimensions of this complexity. The approach involves the transgenic
expression of a misfolded mutant of human preproinsulin, hINSC96Y, which is a
cause of the disease. When expressed in fly imaginal discs, hINSC96Y causes a
reduction of adult structures, including the eye, wing and notum. Eye imaginal
discs exhibit defects in both the structure and arrangement of ommatidia. In
the wing, expression of hINSC96Y leads to ectopic expression of veins and
mechano-sensory organs, indicating disruption of wild type signaling processes
regulating cell fates. These readily measurable disease phenotypes are
sensitive to temperature, gene dose and sex. Mutant (but not wild type)
proinsulin expression in the eye imaginal disc induces IRE1-mediated Xbp1
alternative splicing, a signal for endoplasmic reticulum stress response
activation, and produces global change in gene expression. Mutant hINS
transgene tester strains, when crossed to stocks from the Drosophila Genetic
Reference Panel produces F1 adults with a continuous range of disease
phenotypes and large broad-sense heritability. Surprisingly, the severity of
mutant hINS-induced disease in the eye is not correlated with that in the notum
in these crosses, nor with eye reduction phenotypes caused by the expression of
two dominant eye mutants acting in two different eye development pathways, Drop
(Dr) or Lobe (L) when crossed into the same genetic backgrounds. The tissue
specificity of genetic variability for mutant hINS-induced disease thus has its
own distinct signature. The genetic dominance of disease-specific phenotypic
variability makes this approach amenable to genome-wide association study
(GWAS) in a simple F1 screen of natural variation.


title: Contract agreements via logic

abstract:
  We relate two contract models: one based on event structures and game theory,
and the other one based on logic. In particular, we show that the notions of
agreement and winning strategies in the game-theoretic model are related to
that of provability in the logical model.


title: Elliptic curves with torsion group Z/8Z or Z/2Z x Z/6Z

abstract:
  We show the existence of families of elliptic curves over Q whose generic
rank is at least 2 for the torsion groups Z/8Z and Z/2Z x Z/6Z. Also in both
cases we prove the existence of infinitely many elliptic curves, which are
parameterized by the points of an elliptic curve with positive rank, with such
torsion group and rank at least 3. These results represent an improvement of
previous results by Campbell, Kulesz, Lecacheux, Dujella and Rabarison where
families with rank at least 1 were constructed in both cases.


title:
The distribution of directions in an affine lattice: two-point
  correlations and mixed moments

abstract:
  We consider an affine Euclidean lattice and record the directions of all
lattice vectors of length at most $T$. Str\"ombergsson and the second author
proved in [Annals of Math.~173 (2010), 1949--2033] that the distribution of
gaps between the lattice directions has a limit as $T$ tends to infinity. For a
typical affine lattice, the limiting gap distribution is universal and has a
heavy tail; it differs distinctly from the gap distribution observed in a
Poisson process, which is exponential. The present study shows that the
limiting two-point correlation function of the projected lattice points exists
and is Poissonian. This answers a recent question by Boca, Popa and Zaharescu
[arXiv:1302.5067]. The existence of the limit is subject to a certain
Diophantine condition. We also establish the convergence of more general mixed
moments.


title: A Hierarchical Modulation for Upgrading Digital Broadcast Systems

abstract:
  A hierarchical modulation scheme is proposed to upgrade an existing digital
broadcast system, such as satellite TV, or satellite radio, by adding more data
in its transmission. The hierarchical modulation consists of a basic
constellation, which is the same as in the original system, and a secondary
constellation, which carries the additional data for the upgraded system. The
upgraded system with the hierarchical modulation is backward compatible in the
sense that receivers that have been deployed in the original system can
continue receiving data in the basic constellation. New receivers can be
designed to receive data carried in the secondary constellation, as well as
those in the basic constellation. Analysis will be performed to show the
tradeoff between bit rate of the data in secondary constellation and the
penalty to the performance of receiving the basic constellation.


title: Aging of CKN: Modulus versus conductivity analysis

abstract:
  It was recently reported that the electrical modulus peaks narrows upon
annealing of the ionic system CKN [Paluch et al., Phys. Rev. Lett. 110, 015702
(2013)], which was interpreted as providing evidence of dynamic heterogeneity
of this glass-forming liquid. An analysis of the same data in terms of the ac
conductivity shows no shape changes, however. We discuss the relation between
both findings and show further that the ac conductivity conforms to the
prediction of the random barrier model (RBM) at all times during the annealing.


title:
Generating functions for real character degree sums of finite general
  linear and unitary groups

abstract:
  We compute generating functions for the sum of the real-valued character
degrees of the finite general linear and unitary groups, through symmetric
function computations. For the finite general linear group, we get a new
combinatorial proof that every real-valued character has Frobenius-Schur
indicator 1, and we obtain some q-series identities. For the finite unitary
group, we expand the generating function in terms of values of Hall-Littlewood
functions, and we obtain combinatorial expressions for the character degree
sums of real-valued characters with Frobenius-Schur indicator 1 or -1.


title: Symmetry-adapted Wannier functions in the maximal localization procedure

abstract:
  A procedure to construct symmetry-adapted Wannier functions in the framework
of the maximally-localized Wannier function approach[Marzari and Vanderbilt,
Phys. Rev. B \textbf{56}, 12847 (1997); Souza, Marzari, and Vanderbilt,
\textit{ibid.} \textbf{65}, 035109 (2001)] is presented. In this scheme the
minimization of the spread functional of the Wannier functions is performed
with constraints that are derived from symmetry properties of the specified set
of the Wannier functions and the Bloch functions used to construct them,
therefore one can obtain a solution that does not necessarily yield the global
minimum of the spread functional. As a test of this approach, results of
atom-centered Wannier functions for GaAs and Cu are presented.


title: On double cosets in free groups

abstract:
  It is shown that for any finitely generated subgroups H and K of a free group
F, and for any element g in F the double coset HgK is closed in the profinite
topology of F.


title:
Providing Local Content in a Hybrid Single Frequency Network using
  Hierarchical Modulation

abstract:
  A hierarchical modulation method is proposed for providing local content in a
hybrid satellite and terrestrial single frequency network such DVB-SH. The
hierarchical modulation is used to transmit both global and local content in
terrestrial transmitters. The global content is transmitted with high priority
layer of the hierarchical modulation, and the local content is modulated with
the low priority layer of the hierarchical modulation. The satellite transmits
global content only. The performance of the hierarchical system for both global
and local content is analyzed.


title: Production of translationally cold barium monohalide ions

abstract:
  We have produced sympathetically cooled barium monohalide ions BaX$^+$ (X =
F, Cl, Br) by reacting trapped, laser cooled Ba$^+$ ions with room temperature
gas phase neutral halogen-containing molecules. Reaction rates for two of these
(SF$_6$ and CH$_3$Cl) have been measured and are in agreement with classical
models. BaX$^+$ ions are promising candidates for cooling to the rovibrational
ground state, and our method presents a straightforward way to produce these
polar molecular ions.


title: Optimal Decentralized State-Feedback Control with Sparsity and Delays

abstract:
  This work presents the solution to a class of decentralized linear quadratic
state-feedback control problems, in which the plant and controller must satisfy
the same combination of delay and sparsity constraints. Using a novel
decomposition of the noise history, the control problem is split into
independent subproblems that are solved using dynamic programming. The approach
presented herein both unifies and generalizes many existing results.


title: Digital predistortion for power amplifiers using separable functions

abstract:
  This paper is concerned with digital predistortion for linearization of RF
high power amplifiers (HPAs). It has two objectives. First, we establish a
theoretical framework for a generic predistorter system, and show that if a
postdistorter exists, then it is also a predistorter, and therefore, the
predistorter and postdistorter are equivalent. This justifies the indirect
learning methods for a large class of HPAs. Secondly, we establish a systematic
and general structure for a predistorter that is capable of compensating
nonlinearity for a large variety of HPAs. This systematic structure is derived
using approximation by separable functions, and avoids selection of
predistorters based on the assumption of HPA models traditionally done in the
literature.


title:
A panchromatic view of the restless SN2009ip reveals the explosive
  ejection of a massive star envelope

abstract:
  The 2012 explosion of SN2009ip raises questions about our understanding of
the late stages of massive star evolution. Here we present a comprehensive
study of SN2009ip during its remarkable re-brightening(s). High-cadence
photometric and spectroscopic observations from the GeV to the radio band
obtained from a variety of ground-based and space facilities (including the
VLA, Swift, Fermi, HST and XMM) constrain SN2009ip to be a low energy (E~ 10^50
erg for an ejecta mass ~ 0.5 Msun) and likely asymmetric explosion in a complex
medium shaped by multiple eruptions of the restless progenitor star. Most of
the energy is radiated as a result of the shock breaking out through a dense
shell of material located at 5x10^14 cm with M~0.1 Msun, ejected by the
precursor outburst ~40 days before the major explosion. We interpret the NIR
excess of emission as signature of dust vaporization of material located
further out (R>4x 10^15 cm), the origin of which has to be connected with
documented mass loss episodes in the previous years. Our modeling predicts
bright neutrino emission associated with the shock break-out if the cosmic ray
energy is comparable to the radiated energy. We connect this phenomenology with
the explosive ejection of the outer layers of the massive progenitor star, that
later interacted with material deposited in the surroundings by previous
eruptions. Future observations will reveal if the luminous blue variable (LBV)
progenitor star survived. Irrespective of whether the explosion was terminal,
SN2009ip brought to light the existence of new channels for sustained episodic
mass-loss, the physical origin of which has yet to be identified.


title: Efficient and Robust Persistent Homology for Measures

abstract:
  We extend the notion of the distance to a measure from Euclidean space to
probability measures on general metric spaces as a way to do topological data
analysis in a way that is robust to noise and outliers. We then give an
efficient way to approximate the sub-level sets of this function by a union of
metric balls and extend previous results on sparse Rips filtrations to this
setting. This robust and efficient approach to topological data analysis is
illustrated with several examples from an implementation.


title: Expectation-maximization for logistic regression

abstract:
  We present a family of expectation-maximization (EM) algorithms for binary
and negative-binomial logistic regression, drawing a sharp connection with the
variational-Bayes algorithm of Jaakkola and Jordan (2000). Indeed, our results
allow a version of this variational-Bayes approach to be re-interpreted as a
true EM algorithm. We study several interesting features of the algorithm, and
of this previously unrecognized connection with variational Bayes. We also
generalize the approach to sparsity-promoting priors, and to an online method
whose convergence properties are easily established. This latter method
compares favorably with stochastic-gradient descent in situations with marked
collinearity.


title:
Gohberg lemma, compactness, and essential spectrum of operators on
  compact Lie groups

abstract:
  In this paper we prove a version of the Gohberg lemma on compact Lie groups
giving an estimate from below for the distance from a given operator to the set
of compact operators on compact Lie groups. As a consequence, we prove several
results on bounds for the essential spectrum and a criterion for an operator to
be compact. The conditions are given in terms of the matrix-valued symbols of
operators.


title:
Physical characteristics of G331.5-0.1: The luminous central region of a
  Giant Molecular Cloud

abstract:
  We report molecular line and dust continuum observations toward the high-mass
star forming region G331.5-0.1, one of the most luminous regions of massive
star-formation in the Milky Way, located at the tangent region of the Norma
spiral arm, at a distance of 7.5 kpc. Molecular emission was mapped toward the
G331.5-0.1 GMC in the CO (J=1-0) and C18O (J=1-0) lines with NANTEN, while its
central region was mapped in CS (J=2-1 and J=5-4) with SEST, and in CS (J=7-6)
and 13CO (J=3-2) with ASTE. Continuum emission mapped at 1.2 mm with SIMBA and
at 0.87 mm with LABOCA reveal the presence of six compact and luminous dust
clumps, making this source one of the most densely populated central regions of
a GMC in the Galaxy. The dust clumps are associated with molecular gas and they
have the following average properties: size of 1.6 pc, mass of 3.2x10^3 Msun,
molecular hydrogen density of 3.7x10^4 cm^{-3}, dust temperature of 32 K, and
integrated luminosity of 5.7x10^5 Lsun, consistent with values found toward
other massive star forming dust clumps. The CS and 13CO spectra show the
presence of two velocity components: a high-velocity component at ~ -89 km
s^{-1}, seen toward four of the clumps, and a low-velocity component at ~ -101
km s^{-1} seen toward the other two clumps. Radio continuum emission is present
toward four of the molecular clumps, with spectral index estimated for two of
them of 0.8+-0.2 and 1.2+-0.2. A high-velocity molecular outflow is found at
the center of the brightest clump, with a line width of 26 km s^{-1} (FWHM) in
CS (J=7-6). Observations of SiO (J=7-6 and J=8-7), and SO (J_K=8_8-7_7 and
J_K=8_7-7_6) lines provide estimates of the gas rotational temperature toward
this outflow >120 K and >75 K, respectively.


title:
Quasiparticle Interference on the Surface of Topological Crystalline
  Insulator Pb(1-x)Sn(x)Se

abstract:
  Topological crystalline insulators represent a novel topological phase of
matter in which the surface states are protected by discrete point
group-symmetries of the underlying lattice. Rock-salt lead-tin-selenide alloy
is one possible realization of this phase which undergoes a topological phase
transition upon changing the lead content. We used scanning tunneling
microscopy (STM) and angle resolved photoemission spectroscopy (ARPES) to probe
the surface states on (001) Pb$_{1-x}$Sn$_{x}$Se in the topologically
non-trivial (x=0.23) and topologically trivial (x=0) phases. We observed
quasiparticle interference with STM on the surface of the topological
crystalline insulator and demonstrated that the measured interference can be
understood from ARPES studies and a simple band structure model. Furthermore,
our findings support the fact that Pb$_{0.77}$Sn$_{0.23}$Se and PbSe have
different topological nature.


title: On the comprehension schema in LP=>

abstract: We construct a model of the comprehension schema in the logic LP=>.


title: Wieferich pairs and Barker sequences, II

abstract:
  We show that if a Barker sequence of length $n>13$ exists, then either
$n=3979201339721749133016171583224100$, or $n > 4\cdot10^{33}$. This improves
the lower bound on the length of a long Barker sequence by a factor of nearly
2000. We also obtain 18 additional integers $n<10^{50}$ that cannot be ruled
out as the length of a Barker sequence, and find more than 237000 additional
candidates $n<10^{100}$. These results are obtained by completing extensive
searches for Wieferich prime pairs and using them, together with a number of
arithmetic restrictions on $n$, to construct qualifying integers below a given
bound. We also report on some updated computations regarding open cases of the
circulant Hadamard matrix problem.


title: Gaseous CO Abundance---An Evolutionary Tracer for Molecular Clouds

abstract:
  Planck cold clumps are among the most promising objects to investigate the
initial conditions of the evolution of molecular clouds. In this work, by
combing the dust emission data from the survey of Planck satellite with the
molecular data of $^{12}$CO/$^{13}$CO (1-0) lines from observations with the
Purple Mountain Observatory (PMO) 13.7 m telescope, we investigate the CO
abundance, CO depletion and CO-to-H$_{2}$ conversion factor of 674 clumps in
the early cold cores (ECC) sample. The median and mean values of the CO
abundance are 0.89$\times10^{-4}$ and 1.28$\times10^{-4}$, respectively. The
mean and median of CO depletion factor are 1.7 and 0.9, respectively. The
median value of $X_{CO-to-H_{2}}$ for the whole sample is $2.8\times10^{20}$
cm$^{-2}$K$^{-1}$km$^{-1}$ s. The CO abundance, CO depletion factor and
CO-to-H$_{2}$ conversion factor are strongly (anti-)correlated to other
physical parameters (e.g. dust temperature, dust emissivity spectral index,
column density, volume density and luminosity-to-mass ratio). To conclude, the
gaseous CO abundance can be used as an evolutionary tracer for molecular
clouds.


title: New insights on the distant AGN population

abstract:
  Current X-ray surveys have proved to be essential tools in order to identify
and study AGNs across cosmic time. However, there is evidence that the most
heavily obscured AGNs are largely missing even in the deepest surveys. The
search for these obscured AGNs is one of the most outstanding issues of
extragalactic astronomy, since they are expected to make a major contribution
to the high energy peak of the X-ray background (XRB) and might constitute a
particularly active and dusty phase of black hole and galaxy evolution. Using a
newly developed SED fitting technique to decompose the AGN from the
star-formation emission in the infrared band we identify a sample of 17 IR
bright quasars at z=1-3. For the majority of these sources the X-ray spectrum
is well characterised by an absorbed power law model, revealing that ~25% of
the sources are unabsorbed; the remainder of these IR quasars have
moderate-to-high absorption (N_H>10^23 cm^-2), and ~25% are not detected in the
X-rays and are likely to be Compton thick (N_H>10^24 cm^-2). We therefore find
a much higher fraction of obscured than unobscured quasars, indicating that a
large fraction of the luminous black hole accretion was very heavily obscured
at z~2.


title:
Hyperfine-frequency shifts of alkali-metal atoms during long-range
  collisions

abstract:
  Collisions with chemically inert atoms or molecules change the hyperfine
coupling of an alkali-metal atom through the hyperfine-shift interaction. This
interaction is responsible for the pressure shifts of the microwave resonances
of alkali-metal atoms in buffer gases, is an important spin interaction in
alkali-metal--noble-gas van der Waals molecules, and is anticipated to enable
the magnetoassociation of ultracold molecules such as RbSr. An improved
estimate is presented for the long-range asymptote of this interaction for Na,
K, Rb, and Cs. To test the results, the change in hyperfine coupling due to a
static electric field is estimated and reasonable agreement is found.


title:
Numerical Treatment of Anisotropic Radiation Field Coupling with the
  Relativistic Resistive Magnetofluids

abstract:
  We develop a numerical scheme for solving a fully special relativistic
resistive radiation magnetohydrodynamics. Our code guarantees conservations of
total mass, momentum and energy. Radiation energy density and radiation flux
are consistently updated using the M-1 closure method, which can resolve an
anisotropic radiation fields in contrast to the Eddington approximation as well
as the flux-limited diffusion approximation. For the resistive part, we adopt a
simple form of the Ohm's law. The advection terms are explicitly solved with an
approximate Riemann solver, mainly HLL scheme, and HLLC and HLLD schemes for
some tests. The source terms, which describe the gas-radiation interaction and
the magnetic energy dissipation, are implicitly integrated, relaxing the
Courant-Friedrichs-Lewy condition even in optically thick regime or a large
magnetic Reynolds number regime. Although we need to invert $4\times 4$ (for
gas-radiation interaction) and $3\times 3$ (for magnetic energy dissipation)
matrices at each grid point for implicit integration, they are obtained
analytically without preventing massive parallel computing. We show that our
code gives reasonable outcomes in numerical tests for ideal
magnetohydrodynamics, propagating radiation, and radiation hydrodynamics. We
also applied our resistive code to the relativistic Petschek type magnetic
reconnection, revealing the reduction of the reconnection rate via the
radiation drag.


title:
Hyperentanglement concentration for two-photon four-qubit systems with
  linear optics

abstract:
  Hyperentanglement, defined as the entanglement in several degrees of freedom
(DOFs) of a quantum system, has attracted much attention recently. Here we
investigate the possibility of concentrating the two-photon four-qubit systems
in partially hyperentangled states in both the spatial mode and the
polarization DOFs with linear optics. We first introduce our
parameter-splitting method to concentrate the systems in the partially
hyperentangled states with known parameters, including partially hyperentangled
Bell states and cluster states. Subsequently, we present another two nonlocal
hyperentanglement concentration protocols (hyper-ECPs) for the systems in
partially hyperentangled unknown states, resorting to the Schmidt projection
method. It will be shown that our parameter-splitting method is very efficient
for the concentration of the quantum systems in partially entangled states with
known parameters, resorting to linear-optical elements only. All these four
hyper-ECPs are feasible with current technology and they may be useful in
long-distance quantum communication based on hyperentanglement as they require
only linear optical elements.


title:
Gevrey Regularizing Effect for Solutions of the Non-Cutoff Boltzmann
  Equation in a Particular Case of Soft Potential with Critical Singularity

abstract:
  In this paper we show the Gevrey regularizing effect of solutions to the
non-cutoff spatially homogeneous and inhomogeneous Boltzmann equation for a
particular soft potential with critical singularity s=1/2.


title:
Stable determination of X-ray transforms of time dependent potentials
  from the dynamical Dirichlet-to-Neumann map

abstract:
  We consider compact smooth Riemmanian manifolds with boundary of dimension
greater than or equal to two. For the initial-boundary value problem for the
wave equation with a lower order term $q(t,x)$, we can recover the X-ray
transform of time dependent potentials $q(t,x)$ from the dynamical
Dirichlet-to-Neumann map in a stable way. We derive H\"older stability
estimates for the X-ray transform of $q(t,x)$ which do not require measurements
on the entirety of the boundary. The essential technique involved is the
Gaussian beam Ansatz, and the proofs are done with the minimal assumptions on
the geometry for the Ansatz to be well-defined.


title:
Scalable photonic quantum computing assisted by quantum-dot spin in
  double-sided optical microcavity

abstract:
  We investigate the possibility to achieve scalable photonic quantum computing
by the giant optical circular birefringence induced by a quantum-dot spin in a
double-sided optical microcavity as a result of cavity quantum electrodynamics.
We construct a deterministic controlled-not gate on two photonic qubits by two
single-photon input-output processes and the readout on an electron-medium spin
confined in an optical resonant microcavity. This idea could be applied to
multi-qubit gates on photonic qubits and we give the quantum circuit for a
three-photon Toffoli gate. High fidelities and high efficiencies could be
achieved when the side leakage to the cavity loss rate is low. It is worth
pointing out that our devices work in both the strong and the weak coupling
regimes.


title:
Analysis and Evaluation of the Link and Content Based Focused
  Treasure-Crawler

abstract:
  Indexing the Web is becoming a laborious task for search engines as the Web
exponentially grows in size and distribution. Presently, the most effective
known approach to overcome this problem is the use of focused crawlers. A
focused crawler applies a proper algorithm in order to detect the pages on the
Web that relate to its topic of interest. For this purpose we proposed a custom
method that uses specific HTML elements of a page to predict the topical focus
of all the pages that have an unvisited link within the current page. These
recognized on-topic pages have to be sorted later based on their relevance to
the main topic of the crawler for further actual downloads. In the
Treasure-Crawler, we use a hierarchical structure called the T-Graph which is
an exemplary guide to assign appropriate priority score to each unvisited link.
These URLs will later be downloaded based on this priority. This paper outlines
the architectural design and embodies the implementation, test results and
performance evaluation of the Treasure-Crawler system. The Treasure-Crawler is
evaluated in terms of information retrieval criteria such as recall and
precision, both with values close to 0.5. Gaining such outcome asserts the
significance of the proposed approach.


title:
Quantifying model uncertainty in non-Gaussian dynamical systems with
  observations on mean exit time or escape probability

abstract:
  Complex systems are sometimes subject to non Gaussian alpha stable Levy
fluctuations. A new method is devised to estimate this uncertain parameter and
other system parameters, using observations on either mean exit time or escape
probability for the system evolution. It is based on solving an inverse problem
for a deterministic, non-local partial differential equation via numerical
optimization. The existing methods for estimating parameters require
observations on system state sample paths for long time periods or probability
densities at large spatial ranges. The method proposed here, instead, requires
observations on mean exit time or escape probability only for an arbitrarily
small spatial domain. This new method is beneficial to systems for which mean
exit time or escape probability is feasible to observe.


title: Bredon Homology of Partition Complexes

abstract:
  We prove that the Bredon homology or cohomology of the partition complex with
fairly general coefficients is either trivial or computable in terms of
constructions with the Steinberg module. The argument involves developing a
theory of Bredon homology and cohomology approximation.


title: Decomposition in conic optimization with partially separable structure

abstract:
  Decomposition techniques for linear programming are difficult to extend to
conic optimization problems with general non-polyhedral convex cones because
the conic inequalities introduce an additional nonlinear coupling between the
variables. However in many applications the convex cones have a partially
separable structure that allows them to be characterized in terms of simpler
lower-dimensional cones. The most important example is sparse semidefinite
programming with a chordal sparsity pattern. Here partial separability derives
from the clique decomposition theorems that characterize positive semidefinite
and positive-semidefinite-completable matrices with chordal sparsity patterns.
The paper describes a decomposition method that exploits partial separability
in conic linear optimization. The method is based on Spingarn's method for
equality constrained convex optimization, combined with a fast interior-point
method for evaluating proximal operators.


title:
Conitinuous leafwise harmonic functions on codimension one transversely
  isometric foliations

abstract:
  Let $\FF$ be a codimension one foliation on a closed manifold $M$ which
admits a transverse dimension one Riemannian foliation. Then any continuous
leafwise harmonic functions are shown to be constant on leaves.


title: PT-Symmetric Plasmonic Metamaterials

abstract:
  We theoretically investigate the optical properties of parity-time
(PT)-symmetric three dimensional metamaterials composed of strongly-coupled
planar plasmonic waveguides. By tuning the loss-gain balance, we show how the
initially isotropic material becomes both asymmetric and unidirectional. The
highly tunable optical dispersion of PT -symmetric metamaterials provides a
foundation for designing an entirely new class of three-dimensional bulk
synthetic media, with applications ranging from sub-diffraction-limited optical
lenses to non-reciprocal nanophotonic devices.


title: An integrable evolution equation in geometry

abstract:
  We introduce an integrable Hamiltonian system which Lax deforms the Dirac
operator D=d+d* on a finite simple graph or compact Riemannian manifold. We
show that the nonlinear isospectral deformation always leads to an expansion of
the original space, featuring a fast inflationary start. The nonlinear
evolution leaves the Laplacian L=D^2 invariant so that linear Schroedinger or
wave dynamics is not affected. The expansion has the following effects: a
complex structure can develop and the nonlinear quantum mechanics
asymptotically becomes the linear relativistic Dirac wave equation u''=Lu.
While the later is not aware of the expansion of space and does not see the
emerged complex structure, nor the larger non-commutative geometric setup, the
nonlinear flow is affected by it. The natural Noether symmetries of quantum
mechanics introduced here force to consider space as part of a larger complex
geometry. The nonlinear evolution equation is a symmetry of quantum mechanics
which still features super-symmetry, but it becomes clear why it is invisible:
while the McKean-Singer formulas str(exp(i D(t) t)) = str(exp(-L t))=chi(G)
still hold, the super-partners f,Df are orthogonal only at t=0 and become
parallel or anti-parallel for |t| to infinity.


title: Statistics against irritations: a response to Dickens's apologists

abstract:
  In a recent article (arXiv:0909.2479) I reported the results of the test,
where the takers had to tell the prose of Charles Dickens from the prose of
Edward Bulwer-Lytton. The former is a required reading in school, and the
latter has a bad writing contest named after him. Nevertheless, the test-takers
performed on the level of random guessing. This research has met much
criticism, which I refute the in the present article.


title: Cauchy-Binet for Pseudo-Determinants

abstract:
  The pseudo-determinant Det(A) of a square matrix A is defined as the product
of the nonzero eigenvalues of A. It is a basis-independent number which is up
to a sign the first nonzero entry of the characteristic polynomial of A. We
prove Det(F^T G) = sum_P det(F_P) det(G_P) for any two n times m matrices F,G.
The sum to the right runs over all k times k minors of A, where k is determined
by F and G. If F=G is the incidence matrix of a graph this directly implies the
Kirchhoff tree theorem as L=F^T G is then the Laplacian and det^2(F_P) in {0,1}
is equal to 1 if P is a rooted spanning tree. A consequence is the following
Pythagorean theorem: for any self-adjoint matrix A of rank k, one has Det^2(A)
= sum_P det^2(A_P), where det(A_P) runs over k times k minors of A. More
generally, we prove the polynomial identity det(1+x F^T G) = sum_P x^{|P|}
det(F_P) det(G_P) for classical determinants det, which holds for any two n
times m matrices F,G and where the sum on the right is taken over all minors P,
understanding the sum to be 1 if |P|=0. It implies the Pythagorean identity
det(1+F^T F) = sum_P det^2(F_P) which holds for any n times m matrix F and sums
again over all minors F_P. If applied to the incidence matrix F of a finite
simple graph, it produces the Chebotarev-Shamis forest theorem telling that
det(1+L) is the number of rooted spanning forests in the graph with Laplacian
L.


title: Wormhole Hamiltonian Monte Carlo

abstract:
  In machine learning and statistics, probabilistic inference involving
multimodal distributions is quite difficult. This is especially true in high
dimensional problems, where most existing algorithms cannot easily move from
one mode to another. To address this issue, we propose a novel Bayesian
inference approach based on Markov Chain Monte Carlo. Our method can
effectively sample from multimodal distributions, especially when the dimension
is high and the modes are isolated. To this end, it exploits and modifies the
Riemannian geometric properties of the target distribution to create
\emph{wormholes} connecting modes in order to facilitate moving between them.
Further, our proposed method uses the regeneration technique in order to adapt
the algorithm by identifying new modes and updating the network of wormholes
without affecting the stationary distribution. To find new modes, as opposed to
rediscovering those previously identified, we employ a novel mode searching
algorithm that explores a \emph{residual energy} function obtained by
subtracting an approximate Gaussian mixture density (based on previously
discovered modes) from the target density function.


title:
Analytical study on holographic superconductors for Born-Infeld
  electrodynamics in Gauss-Bonnet gravity with backreactions

abstract:
  We analytically study the holographic superconductors for Born-Infeld
electrodynamics in Gauss-Bonnet gravity with backreactions. We note that the
analytic method is still powerful for this complex system and the results
obtained by the analytical and numerical computations are consistent. We find
that the critical temperature decreases with the increase of the backreactions,
Gauss-Bonnet, and Born-Infeld parameters, which means that increase of the
strength of these effects will make the scalar hair harder to form.
Furthermore, the Gauss-Bonnet factor modifies the critical temperature more
significantly than the backreaction factor. The effect of the Born-Infeld
factor on the critical temperature is weaker than the backreaction factor. We
also show that the critical exponent is not affected by the backreactions,
Gauss-Bonnet gravity, and Born-Infeld electrodynamics.


title: Underground Commissioning of LUX

abstract:
  LUX is a dual-phase xenon TPC designed for the direct detection of dark
matter. Using 370 kg of xenon, LUX is capable of setting a WIMP-nucleon cross
section limit at 2 x 10^-46 cm^2 after 300 days of running. LUX will surpass
all existing dark matter limits for WIMP masses above 10 GeV within weeks of
beginning its science run. Following a successful six month surface run, the
detector has recently been deployed underground, and we expect completed
commission in the near future. Updates on status and results are provided.


title: A further simplification of Tarski's axioms of geometry

abstract:
  A slight modification to one of Tarski's axioms of plane Euclidean geometry
is proposed. This modification allows another of the axioms to be omitted from
the set of axioms and proven as a theorem. This change to the system of axioms
simplifies the system as a whole, without sacrificing the useful modularity of
some of its axioms. The new system is shown to possess all of the known
independence properties of the system on which it was based; in addition,
another of the axioms is shown to be independent in the new system.


title:
A Method for Measuring the $6S_{1/2} \leftrightarrow 5D_{3/2}$ Magnetic
  Dipole Transition Moment in {Ba}$^{+}$

abstract:
  We propose a method for measuring the magnetic dipole (M1) transition moment
of the $6S_{1/2} \big(\mathrm{m}=-1/2\big)\leftrightarrow
5D_{3/2}\big(\mathrm{m}=-1/2\big)$ transition in single trapped Ba$^{+}$ by
exploiting different symmetries in the electric quadrupole (E2) and M1
couplings between the states. The technique is adapted from a previously
proposed method for measuring atomic parity nonconservation in a single trapped
ion [Norval Fortson, Phys. Rev. Lett. \textbf{70}, 17 (1993)]. Knowledge of M1
is crucial for any parity nonconservation measurement in Ba$^{+}$, as laser
coupling through M1 can mimic the parity-violating signal. The magnetic moment
for the transition has been calculated by atomic theory and found to be
dominated by electron-electron correlation effects [B.K. Sahoo et. al., Phys.
Rev. A \textbf{74}, 6 (2006)]. To date the value has not been verified
experimentally. This proposed measurement is therefore an essential step toward
a parity nonconservation experiment in the ion that will also test current
many-body theory. The technique can be adapted for similar parity
nonconservation experiments using other atomic ions, where the magnetic dipole
moment could present similar complications.


title: Characterizations of the Saito-Kurokawa lifting: a survey

abstract:
  There are a variety of characterizations of Saito-Kurokawa lifts from
elliptic modular forms to Siegel modular forms of degree 2. In addition to
giving a survey of known characterizations, we apply a recent result of
Weissauer to provide a number of new and simpler characterizations of
Saito-Kurokawa lifts.


title:
Statistical Methods for Estimating Complexity from Competition
  Experiments between Two Populations

abstract:
  Often a screening or selection experiment targets a cell or tissue, which
presents many possible molecular targets and identifies a correspondingly large
number of ligands. We describe a statistical method to extract an estimate of
the complexity or richness of the set of molecular targets from competition
experiments between distinguishable ligands, including aptamers derived from
combinatorial experiments (SELEX or phage display). In simulations, the
nonparametric statistic provides a robust estimate of complexity from a 100x100
matrix of competition experiments, which is clearly feasible in high-throughput
format. The statistic and method are potentially applicable to other ligand
binding situations.


title: Cyclic symmetries of A_n-quiver representations

abstract:
  This short note contains a combinatorial construction of symmetries arising
in symplectic geometry (partially wrapped or infinitesimal Fukaya categories),
algebraic geometry (derived categories of singularities), and K-theory
(Waldhausen's S-construction). Our specific motivation (in the spirit of
expectations of Kontsevich, and to be taken up in general elsewhere) is a
combinatorial construction of quantizations of Lagrangian skeleta (equivalent
to microlocal sheaves in their many guises). We explain here the one
dimensional case of ribbon graphs where the main result of this paper gives an
immediate solution.


title: Life After Earth

abstract:
  A recent study reported that there is evidence life may have originated prior
to the formation of the Earth. That conclusion was based on a regression
analysis of a certain data set involving evolution of functional genome size
across major phyla. Here it is shown that if measurement errors and
"confidence" intervals are taken into account, then the regression analysis of
the same data set leads to conclusions that allow for life to have appeared
after the formation of the Earth.


title:
Adaptive long-range migration promotes cooperation under tempting
  conditions

abstract:
  Migration is a fundamental trait in humans and animals. Recent studies
investigated the effect of migration on the evolution of cooperation, showing
that contingent migration favors cooperation in spatial structures. In those
studies, only local migration to immediate neighbors was considered, while
long-range migration has not been considered yet, partly because the long-range
migration has been generally regarded as harmful for cooperation as it would
bring the population to a well-mixed state that favors defection. Here, we
studied the effects of adaptive long-range migration on the evolution of
cooperation through agent-based simulations of a spatial Prisoner's Dilemma
game where individuals can jump to a farther site if they are surrounded by
more defectors. Our results show that adaptive long-range migration strongly
promotes cooperation, especially under conditions where the temptation to
defect is considerably high. These findings demonstrate the significance of
adaptive long-range migration for the evolution of cooperation.


title: A study of saturated tensor cone for symmetrizable Kac-Moody algebras

abstract:
  Let $\fg$ be a symmetrizable Kac-Moody Lie algebra with the standard Cartan
subalgebra $\fh$ and the Weyl group $W$. Let $P_+$ be the set of dominant
integral weights. For $\lambda \in P_+$, let $L(\lambda)$ be the irreducible,
integrable, highest weight representation of $\fg$ with highest weight
$\lambda$. For a positive integer $s$, define the {\em saturated tensor
semigroup} as \begin{align*} \Gamma_s:= \{(\lambda_1, \dots, \lambda_s,\mu)\in
P_+^{s+1}: \exists\, N>1 \,\,\text{with}\,\, L(N\mu)\subset
L(N\lambda_1)\otimes \dots \otimes L(N\lambda_s)\}. \end{align*} The aim of
this paper is to begin a systematic study of $\Gamma_s$ in the infinite
dimensional symmetrizable Kac-Moody case. In this paper, we produce a set of
necessary inequalities satisfied by $\Gamma_s$. We further prove that any
integer $d>0$ is a saturation factor for $A^{(1)}_1$ and 4 is a saturation
factor for $A^{(2)}_2$.


title: Rouquier's conjecture and diagrammatic algebra

abstract:
  We prove a conjecture of Rouquier relating the decomposition numbers in
category $\mathcal{O}$ for a cyclotomic rational Cherednik algebra to Uglov's
canonical basis of a higher level Fock space. Independent proofs of this
conjecture have also recently been given by Rouquier, Shan, Varagnolo and
Vasserot and by Losev, using different methods.
  Our approach is to develop two diagrammatic models for this category
$\mathcal{O}$; while inspired by geometry, these are purely diagrammatic
algebras, which we believe are of some intrinsic interest. In particular, we
can quite explicitly describe the representations of the Hecke algebra that are
hit by projectives under the $\mathsf{KZ}$-functor from the Cherednik category
$\mathcal{O}$ in this case, with an explicit basis.
  This algebra has a number of beautiful structures including categorifications
of many aspects of Fock space. It can be understood quite explicitly using a
homogeneous cellular basis which generalizes such a basis given by Hu and
Mathas for cyclotomic KLR algebras. Thus, we can transfer results proven in
this diagrammatic formalism to category $\mathcal{O}$ for a cyclotomic rational
Cherednik algebra, including the connection of decomposition numbers to
canonical bases mentioned above, and an action of the affine braid group by
derived equivalences between different blocks.


title: Sensitive Ants for Denial Jamming Attack on Wireless Sensor Network

abstract:
  A new defence mechanism for different jamming attack on Wireless Sensor
Network (WSN) based on ant system it is introduced. The artificial sensitive
ants react on network attacks in particular based on their sensitivity level.
The information is re-directed from the attacked node to its appropriate
destination node. It is analyzed how are detected and isolated the jamming
attacks with mobile agents in general and in particular with the newly
ant-based sensitive approach.


title:
Quenched invariance principles for random walks and elliptic diffusions
  in random media with boundary

abstract:
  Via a Dirichlet form extension theorem and making full use of two-sided heat
kernel estimates, we establish quenched invariance principles for random walks
in random environments with a boundary. In particular, we prove that the random
walk on a supercritical percolation cluster or among random conductances
bounded uniformly from below in a half-space, quarter-space, etc., converges
when rescaled diffusively to a reflecting Brownian motion, which has been one
of the important open problems in this area. We establish a similar result for
the random conductance model in a box, which allows us to improve existing
asymptotic estimates for the relevant mixing time. Furthermore, in the
uniformly elliptic case, we present quenched invariance principles for domains
with more general boundaries.


title:
Partition Consistency: A Case Study in Modeling Systems with Weak Memory
  Consistency and Proving Correctness of their Implementations

abstract:
  Multiprocess systems, including grid systems, multiprocessors and multicore
computers, incorporate a variety of specialized hardware and software
mechanisms, which speed computation, but result in complex memory behavior. As
a consequence, the possible outcomes of a concurrent program can be unexpected.
A memory consistency model is a description of the behaviour of such a system.
Abstract memory consistency models aim to capture the concrete implementations
and architectures. Therefore, formal specification of the implementation or
architecture is necessary, and proofs of correspondence between the abstract
and the concrete models are required.
  This paper provides a case study of this process. We specify a new model,
partition consistency, that generalizes many existing consistency models. A
concrete message-passing network model is also specified. Implementations of
partition consistency on this network model are then presented and proved
correct. A middle level of abstraction is utilized to facilitate the proofs.
All three levels of abstraction are specified using the same framework. The
paper aims to illustrate a general methodology and techniques for specifying
memory consistency models and proving the correctness of their implementations.


title:
Investigation on spectral behavior of Solar Transients and their
  Interrelationship

abstract:
  We probe the spectral hardening of solar flares emission in view of
associated solar proton events (SEPs) at earth and coronal mass ejection (CME)
acceleration as a consequence. In this investigation we undertake 60 SEPs of
the Solar Cycle 23 alongwith associated Solar Flares and CMEs. We employ the
X-ray emission in Solar flares observed by Reuven Ramaty Higly Energy Solar
Spectroscopic Imager (RHESSI) in order to estimate flare plasma parameters.
Further, we employ the observations from Geo-stationary Operational
Environmental Satellites (GOES) and Large Angle and Spectrometric Coronagraph
(LASCO), for SEPs and CMEs parameter estimation respectively. We report a good
association of soft-hard-harder (SHH) spectral behavior of Flares with
occurrence of Solar Proton Events for 16 Events (observed by RHESSI associated
with protons). In addition, we have found a good correlation (R=0.71) in SEPs
spectral hardening and CME velocity. We conclude that the Protons as well as
CMEs gets accelerated at the Flare site and travel all the way in
interplanetary space and then by re-acceleration in interplanetary space CMEs
produce Geomagnetic Storms in geospace. This seems to be a statistically
significant mechanism of the SEPs and initial CME acceleration in addition to
the standard scenario of SEP acceleration at the shock front of CMEs.


title: Measure of Self-Affine Sets and Associated Densities

abstract:
  Let $B$ be an $n\times n$ real expanding matrix and $\mathcal{D}$ be a finite
subset of $\mathbb{R}^n$ with $0\in\mathcal{D}$. The self-affine set
$K=K(B,\mathcal{D})$ is the unique compact set satisfying the set-valued
equation $BK=\displaystyle\bigcup_{d\in\mathcal{D}}(K+d)$. In the case where
$\text{card}(\mathcal{D})=\lvert\det B\rvert,$ we relate the Lebesgue measure
of $K(B,\mathcal{D})$ to the upper Beurling density of the associated measure
$\mu=\lim\limits_{s\to\infty}\sum\limits_{\ell_0,\dotsc,\ell_{s-1}\in\mathcal{D}}\delta_{\ell_0+B\ell_1+\dotsb+B^{s-1}\ell_{s-1}}.$
If, on the other hand, $\text{card}(\mathcal{D})<\lvert\det B\rvert$ and $B$ is
a similarity matrix, we relate the Hausdorff measure $\mathcal{H}^s(K)$, where
$s$ is the similarity dimension of $K$, to a corresponding notion of upper
density for the measure $\mu$.


title: Nonlinearity in oscillating bridges

abstract:
  We first recall several historical oscillating bridges that, in some cases,
led to collapses. Some of them are quite recent and show that, nowadays,
oscillations in suspension bridges are not yet well understood. Next, we survey
some attempts to model bridges with differential equations. Although these
equations arise from quite different scientific communities, they display some
common features. One of them, which we believe to be incorrect, is the
acceptance of the linear Hooke law in elasticity. This law should be used only
in presence of small deviations from equilibrium, a situation which does not
occur in strongly oscillating bridges. Then we discuss a couple of recent
models whose solutions exhibit self-excited oscillations, the phenomenon
visible in real bridges. This suggests a different point of view in modeling
equations and gives a strong hint how to modify the existing models in order to
obtain a reliable theory. The purpose of this paper is precisely to highlight
the necessity of revisiting classical models, to introduce reliable models, and
to indicate the steps we believe necessary to reach this target.


title: Some comments on `Equation for the second virial coefficient`

abstract:
  The second viral coefficient calculated using the equation suggested in the
paper of Kaplun A.B., Meshalkin A.B. Equation for the second virial coefficient
published in High temperature high pressure, 1999, Volume 31, pages 253-258 is
compared with experimental data for helium, hydrogen, neon, argon, krypton,
xenon, carbon dioxide, water, ammonia, methane, ethylene. It is shown the
formula cannot describe the temperature dependence of the experimental data on
the second virial coefficient for the all above substances within the
experimental error over the investigated temperature interval. The latter is in
controversy with the derivations of the paper mentioned above. It is also shown
the formula cannot describe the recommended data for the second virial
coefficient within their uncertainties for helium, hydrogen, neon, argon,
krypton and methane.


title:
H\"older Regularity For Integro-Differential Equations With Nonlinear
  Directional Dependence

abstract:
  We prove H\"older regularity results for a class of nonlinear elliptic
integro-differential operators with integration kernels whose ellipticity
bounds are strongly directionally dependent. These results extend those in [9]
and are also uniform as the order of operators approaches 2.


title:
Generalized Shemesh criterion, common invariant subspaces and
  irreducible completely positive superoperators

abstract:
  Assume that $A_{1},...,A_{s}$ are complex $n\times n$ matrices. We give a
computable criterion for existence of a common eigenvector of $A_{i}$ which
generalize the result of D. Shemesh established for two matrices. We use this
criterion to prove some necessary and sufficient condition for $A_{i}$ to have
a common invariant subspace of dimension $d$, $2\leq d<n$, if every $A_{i}$ has
pairwise different eigenvalues. Finally, we observe that the set of all
matrices having multiple eigevalues has Lebesgue measure 0 and thus the
condition is sufficient in practical applications. Being motivated by quantum
information theory, we give a flavour of such applications for irreducible
completely positive superoperators.


title:
Conditional Expectation of a Markov Kernel Given Another with Some
  Applications in Statistical Inference and Disease Diagnosis

abstract:
  Markov kernels play a decisive role in probability and mathematical
statistics theories, and are an extension of the concepts of sigma-field and
statistic. Concepts such as independence, sufficiency, completeness,
ancillarity or conditional distribution have been extended previously to Markov
kernels. In this paper, the concept of conditional expectation of a Markov
kernel given another is introduced, setting its first properties. An
application to clinical diagnosis is provided, obtaining {an} optimality
property of the predictive values of a diagnosis test. In a statistical
framework, this new probabilistic tool is used to extend to Markov kernels the
theorems of {Rao-Blackwell} and Lehmann-Scheff\'e. A result about the
completeness of a sufficient statistic is obtained in passing by properly
enlarging the family of probabilities. As a final statistical scholium, a
generalization of a result about the completeness of the family of
nonrandomized estimators is given.