title: Anomalous Higgs-boson coupling effects in HWW production at the LHC

abstract:
  We study the LHC associated production of a Higgs boson and a W^+W^-
vector-boson pair at 14 TeV, in the Standard Model and beyond. We consider
different signatures corresponding to the cleanest H and W decay channels, and
discuss the potential of the high-luminosity phase of the LHC. In particular,
we investigate the sensitivity of the HWW production to possible anomalous
Higgs couplings to vector bosons and fermions. Since the b-quark initiated
partonic channel contributes significantly to this process, we find a moderate
sensitivity to both the size and sign of an anomalous top-quark Yukawa
coupling, because perturbative unitarity in the standard model implies a
destructive interference in the b b-bar subprocess. We show that a combination
of various signatures can reach a ~9 standard-deviation sensitivity in the
presently allowed negative region of the top-Higgs coupling, if not previously
excluded.


title:
Variability-based AGN selection using image subtraction in the SDSS and
  LSST era

abstract:
  With upcoming all sky surveys such as LSST poised to generate a deep digital
movie of the optical sky, variability-based AGN selection will enable the
construction of highly-complete catalogs with minimum contamination. In this
study, we generate $g$-band difference images and construct light curves for
QSO/AGN candidates listed in SDSS Stripe 82 public catalogs compiled from
different methods, including spectroscopy, optical colors, variability, and
X-ray detection. Image differencing excels at identifying variable sources
embedded in complex or blended emission regions such as Type II AGNs and other
low-luminosity AGNs that may be omitted from traditional photometric or
spectroscopic catalogs. To separate QSOs/AGNs from other sources using our
difference image light curves, we explore several light curve statistics and
parameterize optical variability by the characteristic damping timescale
($\tau$) and variability amplitude. By virtue of distinguishable variability
parameters of AGNs, we are able to select them with high completeness of 93.4%
and efficiency (i.e., purity) of 71.3%. Based on optical variability, we also
select highly variable blazar candidates, whose infrared colors are consistent
with known blazars. One third of them are also radio detected. With the X-ray
selected AGN candidates, we probe the optical variability of X-ray detected
optically-extended sources using their difference image light curves for the
first time. A combination of optical variability and X-ray detection enables us
to select various types of host-dominated AGNs. Contrary to the AGN unification
model prediction, two Type II AGN candidates (out of 6) show detectable
variability on long-term timescales like typical Type I AGNs. This study will
provide a baseline for future optical variability studies of extended sources.


title:
Robotic Laser-Adaptive-Optics Imaging of 715 Kepler Exoplanet Candidates
  using Robo-AO

abstract:
  The Robo-AO Kepler Planetary Candidate Survey is designed to observe every
Kepler planet candidate host star with laser adaptive optics imaging to search
for blended nearby stars, which may be physically associated companions and/or
responsible for transit false positives. In this paper we present the results
from the 2012 observing season, searching for stars close to 715 representative
Kepler planet candidate hosts. We find 53 companions, 44 of which are new
discoveries. We detail the Robo-AO survey data reduction methods including a
method of using the large ensemble of target observations as mutual
point-spread-function references, along with a new automated
companion-detection algorithm designed for large adaptive optics surveys. Our
survey is sensitive to objects from 0.15" to 2.5" separation, with contrast
ratios up to delta-m~6. We measure an overall nearby-star-probability for
Kepler planet candidates of 7.4% +/- 1.0%, and calculate the effects of each
detected nearby star on the Kepler-measured planetary radius. We discuss
several KOIs of particular interest, including KOI-191 and KOI-1151, which are
both multi-planet systems with detected stellar companions whose unusual
planetary system architecture might be best explained if they are "coincident
multiple" systems, with several transiting planets shared between the two
stars. Finally, we detect 2.6-sigma evidence for <15d-period giant planets
being 2-3 times more likely be found in wide stellar binaries than smaller
close-in planets and all sizes of further-out planets.


title: Confronting Cosmology and New Physics with Fundamental Constants

abstract:
  The values of the fundamental constants such as $\mu = m_P/m_e$, the proton
to electron mass ratio and $\alpha$, the fine structure constant, are sensitive
to the product $\sqrt{\zeta_x^2(w+1)}$ where $\zeta_x$ is a coupling constant
between a rolling scalar field responsible for the acceleration of the
expansion of the universe and the electromagnetic field with x standing for
either $\mu$ or $\alpha$. The dark energy equation of state $w$ can assume
values different than $-1$ in cosmologies where the acceleration of the
expansion is due to a scalar field. In this case the value of both $\mu$ and
$\alpha$ changes with time. The values of the fundamental constants, therefore,
monitor the equation of state and are a valuable tool for determining $w$ as a
function of redshift. In fact the rolling of the fundamental constants is one
of the few definitive discriminators between acceleration due to a cosmological
constant and acceleration due to a quintessence rolling scalar field. $w$ is
often given in parameterized form for comparison with observations. In this
manuscript the predicted evolution of $\mu$, is calculated for a range of
parameterized equation of state models and compared to the observational
constraints on $\Delta \mu / \mu$. We find that the current limits on $\Delta
\mu / \mu$ place significant constraints on linear equation of state models and
on thawing models where $w$ deviates from $-1$ at late times. They also
constrain non-dynamical models that have a constant $w$ not equal to $-1$.
These constraints are an important compliment to geometric tests of $w$ in that
geometric tests are sensitive to the evolution of the universe before the epoch
of observation while fundamental constants are sensitive to the evolution of
the universe after the observational epoch. Abstract truncated.


title:
An analytical model of the large neutral regions during the late stage
  of reionization

abstract:
  In this paper we investigate the nature and distribution of large neutral
regions during the late epoch of reionization. In the "bubble model" of
reionization, the mass distribution of large ionized regions ("bubbles") during
the early stage of reionization is obtained by using the excursion set model,
where the ionization of a region corresponds to the first up-crossing of a
barrier by random trajectories. We generalize this idea, and develop a method
to predict the distribution of large scale neutral regions during the late
stage of reionization, taking into account the ionizing background after the
percolation of HII regions. The large scale neutral regions which we call
"neutral islands" are not individual galaxies or minihalos, but larger regions
where fewer galaxies formed and hence ionized later, and they are identified in
the excursion set model with the first down-crossings of the island barrier.
Assuming that the consumption rate of ionizing background photons is
proportional to the surface area of the neutral islands, we obtained the size
distribution of the neutral islands. We also take the "bubbles-in-island"
effect into account by considering the conditional probability of up-crossing a
bubble barrier after down-crossing the island barrier. We find that this effect
is very important. An additional barrier is set to avoid islands being
percolated through. We find that there is a characteristic scale for the
neutral islands, while the small islands are rapidly swallowed up by the
ionizing background, this characteristic scale does not change much as the
reionization proceeds.


title: Cosmo++: An Object-Oriented C++ Library for Cosmology

abstract:
  This paper introduces a new publicly available numerical library for
cosmology, Cosmo++. The library has been designed using object-oriented
programming techniques, and fully implemented in C++. Cosmo++ introduces a
unified interface for using most of the frequently used numerical methods in
cosmology. Most of the features are implemented in Cosmo++ itself, while a part
of the functionality is implemented by linking to other publicly available
libraries. The most important features of the library are Cosmic Microwave
Background anisotropies power spectrum and transfer function calculations,
likelihood calculations, parameter space sampling tools, sky map simulations,
and mask apodization. Cosmo++ also includes a few mathematical tools that are
frequently used in numerical research in cosmology and beyond. A few simple
examples are included in Cosmo++ to help the user understand the key features.
The library has been fully tested, and we describe some of the important tests
in this paper. Cosmo++ is publicly available at http://cosmo.grigoraslanyan.com

categories: astro-ph.IM astro-ph.CO hep-ph physics.comp-ph


title: Numerical resolution effects on simulations of massive black hole seeds

abstract:
  We have performed high-resolution numerical simulations with the
hydrodynamical AMR code Enzo to investigate the formation of massive seed black
holes in a sample of six dark matter haloes above the atomic cooling threshold.
The aim of this study is to illustrate the effects of varying the maximum
refinement level on the final object formed. The virial temperatures of the
simulated haloes range from $\rm{T} \sim 10000\ \rm{K} - 16000\ \rm{K}$ and
they have virial masses in the range $\rm{M} \sim 2 \times 10^7 \rm{M_{\odot}}$
to $\rm{M} \sim 7 \times 10^7 \rm{M_{\odot}}$ at $z \sim 15$. The outcome of
our six fiducial simulations is both generic and robust. A rotationally
supported, marginally gravitationally stable, disk forms with an exponential
profile. The mass and scale length of this disk depends strongly on the maximum
refinement level used. Varying the maximum refinement level by factors between
1 / 64 to 256 times the fiducial level illustrates the care that must be taken
in interpreting the results. The lower resolution simulations show tentative
evidence that the gas may become rotationally supported out to 20 pc while the
highest resolution simulations show only weak evidence of rotational support
due to the shorter dynamical times for which the simulation runs. The higher
resolution simulations do, however, point to fragmentation at small scales of
the order of $\sim 100$ AU. In the highest resolution simulations a central
object of a few times $10^2\ \rm{M_{\odot}}$ forms with multiple strongly
bound, Jeans unstable, clumps of $\sim 10\ \rm{M_{\odot}}$ and radii of 10 - 20
AU suggesting the formation of dense star clusters in these haloes.


title:
Constraining the Lyman Alpha Escape Fraction with Far-Infrared
  Observations of Lyman Alpha Emitters

abstract:
  We study the far-infrared properties of 498 Lyman Alpha Emitters (LAEs) at
z=2.8, 3.1 and 4.5 in the Extended Chandra Deep Field-South, using 250, 350 and
500 micron data from the Herschel Multi-tiered Extragalactic Survey (HerMES)
and 870 micron data from the LABOCA ECDFS Submillimeter Survey (LESS). None of
the 126, 280 or 92 LAEs at z=2.8, 3.1 and 4.5, respectively, are individually
detected in the far-infrared data. We use stacking to probe the average
emission to deeper flux limits, reaching $1\sigma$ depths of ~0.1 to 0.4 mJy.
The LAEs are also undetected at $\ge3\sigma$ in the stacks, although a
$2.5\sigma$ signal is observed at 870 micron for the z=2.8 sources. We consider
a wide range of far-infrared spectral energy distributions (SEDs), including a
M82 and an Sd galaxy template, to determine upper limits on the far-infrared
luminosities and far-infrared-derived star-formation rates of the LAEs. These
star-formation rates are then combined with those inferred from the Ly$\alpha$
and UV emission to determine lower limits on the LAEs Ly$\alpha$ escape
fraction ($f_{\rm esc}($Ly$\alpha$)). For the Sd SED template, the inferred
LAEs $f_{\rm esc}($Ly$\alpha$) are $\gtrsim30%$ ($1\sigma$) at z=2.8, 3.1 and
4.5, which are all significantly higher than the global $f_{\rm
esc}($Ly$\alpha$) at these redshifts. Thus, if the LAEs $f_{\rm
esc}($Ly$\alpha$) follows the global evolution then they have warmer
far-infrared SEDs than the Sd galaxy template. The average and M82 SEDs produce
lower limits on the LAE $f_{\rm esc}($Ly$\alpha$) of ~10 to 20% ($1\sigma$),
all of which are slightly higher than the global evolution of $f_{\rm
esc}($Ly$\alpha$) but consistent with it at the 2 to 3$\sigma$ level.


title:
The stellar mass function and star formation rate-stellar mass relation
  of galaxies at z ~ 4 - 7

abstract:
  We investigate the evolution of the star formation rate-stellar mass relation
(SFR-M*) and Galaxy Stellar Mass Function (GSMF) of z ~ 4-7 galaxies, using
cosmological simulations run with the smoothed particle hydrodynamics code
P-GADGET3(XXL). We explore the effects of different feedback prescriptions
(supernova driven galactic winds and AGN feedback), initial stellar mass
functions and metal cooling. We show that our fiducial model, with strong
energy-driven winds and early AGN feedback, is able to reproduce the observed
stellar mass function obtained from Lyman-break selected samples of star
forming galaxies at redshift 6 < z < 7. At z ~ 4, observed estimates of the
GSMF vary according to how the sample was selected. Our simulations are more
consistent with recent results from K-selected samples, which provide a better
proxy of stellar masses and are more complete at the high mass end of the
distribution. We find that in some cases simulated and observed SFR-M*
relations are in tension, and this can lead to numerical predictions for the
GSMF in excess of the GSMF observed. By combining the simulated SFR(M*)
relationship with the observed star formation rate function at a given
redshift, we argue that this disagreement may be the result of the uncertainty
in the SFR-M* (Luv-M*) conversion. Our simulations predict a population of
faint galaxies not seen by current observations.


title: Hiding Missing Energy in Missing Energy

abstract:
  Searches for supersymmetry (SUSY) often rely on a combination of hard physics
objects (jets, leptons) along with large missing transverse energy to separate
New Physics from Standard Model hard processes. We consider a class of
``double-invisible'' SUSY scenarios: where squarks, stops and sbottoms have a
three-body decay into two (rather than one) invisible final-state particles.
This occurs naturally when the LSP carries an additional conserved quantum
number under which other superpartners are not charged. In these topologies,
the available energy is diluted into invisible particles, reducing the observed
missing energy and visible energy. This can lead to sizable changes in the
sensitivity of existing searches, dramatically changing the qualitative
constraints on superpartners. In particular, for m_LSP>160 GeV, we find no
robust constraints from the LHC at any squark mass for any generation, while
for lighter LSPs we find significant reductions in constraints. If confirmed by
a full reanalysis from the collaborations, such scenarios allow for the
possibility of significantly more natural SUSY models. While not realized in
the MSSM, such phenomenology occurs naturally in models with mixed sneutrinos,
Dirac gauginos and NMSSM-like models.


title: Dynamical resonance locking in tidally interacting binary systems

abstract:
  We examine the dynamics of resonance locking in detached, tidally interacting
binary systems. In a resonance lock, a given stellar or planetary mode is
trapped in a highly resonant state for an extended period of time, during which
the spin and orbital frequencies vary in concert to maintain the resonance.
This phenomenon is qualitatively similar to resonance capture in planetary
dynamics. We show that resonance locks can accelerate the course of tidal
evolution in eccentric systems and also efficiently couple spin and orbital
evolution in circular binaries. Previous analyses of resonance locking have not
treated the mode amplitude as a fully dynamical variable, but rather assumed
the adiabatic (i.e. Lorentzian) approximation valid only in the limit of
relatively strong mode damping. We relax this approximation, analytically
derive conditions under which the fixed point associated with resonance locking
is stable, and further check these analytic results using numerical
integrations of the coupled mode, spin, and orbital evolution equations. These
show that resonance locking can sometimes take the form of complex limit cycles
or even chaotic trajectories. We provide simple analytic formulae that define
the binary and mode parameter regimes in which resonance locks of some kind
occur (stable, limit cycle, or chaotic). We briefly discuss the astrophysical
implications of our results for white dwarf and neutron star binaries as well
as eccentric stellar binaries.


title: Estimation of Human Body Shape and Posture Under Clothing

abstract:
  Estimating the body shape and posture of a dressed human subject in motion
represented as a sequence of (possibly incomplete) 3D meshes is important for
virtual change rooms and security. To solve this problem, statistical shape
spaces encoding human body shape and posture variations are commonly used to
constrain the search space for the shape estimate. In this work, we propose a
novel method that uses a posture-invariant shape space to model body shape
variation combined with a skeleton-based deformation to model posture
variation. Our method can estimate the body shape and posture of both static
scans and motion sequences of dressed human body scans. In case of motion
sequences, our method takes advantage of motion cues to solve for a single body
shape estimate along with a sequence of posture estimates. We apply our
approach to both static scans and motion sequences and demonstrate that using
our method, higher fitting accuracy is achieved than when using a variant of
the popular SCAPE model as statistical model.


title: Nesting Induced Large Magnetoelasticity in the Iron Arsenide Systems

abstract:
  A novel feature of the iron arsenides is the magnetoelastic coupling between
the long wavelength in-plane strains of the lattice and the collective spin
fluctuations of the electrons near the magnetic ordering wavevectors. Here, we
study its microscopic origin from an electronic model with nested Fermi pockets
and a nominal interaction. We find the couplings diverge with a power-law as
the system is tuned to perfect nesting. Furthermore, the theory reveals how
nematicity is boosted by nesting. These results are relevant for other systems
with nesting driven density wave transitions.


title:
The gravitational two-body problem in the vicinity of the light ring:
  Insights from the black-hole-ring toy model

abstract:
  The physical properties of an axisymmetric black-hole-ring system are studied
analytically within the framework of general relativity to second order in the
dimensionless mass ratio $\mu\equiv m/M$. In particular, we analyze the
asymptotic behaviors of the binding-energy and the total angular-momentum of
the two-body system in the vicinity of the light ring at $R=3M$, where the
circular orbit becomes null. We find that both quantities diverge {\it
quadratically} in $\mu(1-3M/R)^{-1}$ at the light ring. The reported divergent
behavior of the physical quantities stems from the second order spin-orbit
interaction between the black hole and the orbiting object (the dragging of
inertial frames by the orbiting ring). It is shown that this composed
black-hole-ring toy model captures some of the essential features of the
conservative dynamics of the (astrophysically more interesting)
black-hole-particle system. In particular, we show that both systems share the
{\it same} quadratic divergent behavior of the physical quantities near the
light ring. Moreover, we prove that both systems are characterized by the {\it
same} ratio ${{E^{(2)}(R\to 3M)}\over{J^{(2)}(R\to
3M)}}={{1}\over{3\sqrt{3}}}$, where $E^{(2)}$ and $J^{(2)}$ are the divergent
second order (self-interaction) expansion coefficients of the binding-energies
and the angular-momenta of the systems, respectively.


title:
Ab-initio pulsar magnetosphere: three-dimensional particle-in-cell
  simulations of axisymmetric pulsars

abstract:
  We perform first-principles relativistic particle-in-cell simulations of
aligned pulsar magnetosphere. We allow free escape of particles from the
surface of a neutron star and continuously populate the magnetosphere with
neutral pair plasma to imitate pair production. As pair plasma supply
increases, we observe the transition from a charge-separated electrosphere
solution with trapped plasma and no spin-down to a solution close to the ideal
force-free magnetosphere with electromagnetically-dominated pulsar wind. We
calculate the magnetospheric structure, current distribution and spin-down
power of the neutron star. We also discuss particle acceleration in the
equatorial current sheet.


title: On the metric dimension of imprimitive distance-regular graphs

abstract:
  A resolving set for a graph $\Gamma$ is a collection of vertices $S$, chosen
so that for each vertex $v$, the list of distances from $v$ to the members of
$S$ uniquely specifies $v$. The metric dimension of $\Gamma$ is the smallest
size of a resolving set for $\Gamma$. Much attention has been paid to the
metric dimension of distance-regular graphs. Work of Babai from the early 1980s
yields general bounds on the metric dimension of primitive distance-regular
graphs in terms of their parameters. We show how the metric dimension of an
imprimitive distance-regular graph can be related to that of its halved and
folded graphs, but also consider infinite families (including Taylor graphs and
the incidence graphs of certain symmetric designs) where more precise results
are possible.


title:
Infra-red divergences in Light Front Field Theory and Coherent State
  Formalism

abstract:
  We discuss fermion self energy correction in light front QED using a coherent
state basis. We show that if one uses coherent state basis instead of fock
basis to calculate the transition matrix elements the true infrared divergences
in $\delta m^2$ get canceled up to $O(e^4)$ . We show this in Light-front as
well as in Feynman gauge.


title:
The metric dimension of small distance-regular and strongly regular
  graphs

abstract:
  A {\em resolving set} for a graph $\Gamma$ is a collection of vertices $S$,
chosen so that for each vertex $v$, the list of distances from $v$ to the
members of $S$ uniquely specifies $v$. The {\em metric dimension} of $\Gamma$
is the smallest size of a resolving set for $\Gamma$.
  A graph is {\em distance-regular} if, for any two vertices $u,v$ at each
distance $i$, the number of neighbours of $v$ at each possible distance from
$u$ (i.e. $i-1$, $i$ or $i+1$) depends only on the distance $i$, and not on the
choice of vertices $u,v$. The class of distance-regular graphs includes all
distance-transitive graphs and all strongly regular graphs.
  In this paper, we present the results of computer calculations which have
found the metric dimension of all distance-regular graphs on up to 34 vertices,
low-valency distance transitive graphs on up to 100 vertices, strongly regular
graphs on up to 45 vertices, rank-$3$ strongly regular graphs on under 100
vertices, as well as certain other distance-regular graphs.


title:
Estimation of LHC and ILC Capabilities for Precision Higgs Boson
  Coupling Measurements

abstract:
  This paper discusses some aspects of the estimates of Higgs boson coupling
sensitivities for LHC and ILC presented at the Snowmass 2013 meeting. I
estimate the measurement accuracies underlying the CMS presentation to
Snowmass. I present new fits for the ILC capabilities. I present some joints
fits to prospective LHC and ILC data that demonstrates the synergy of the
High-Luminosity LHC and ILC programs. Contributed to the proceedings of the
Snowmass 2013 Community Summer Study.


title: The colour distribution of galaxies at redshift five

abstract:
  We present the results of a study investigating the rest-frame ultra-violet
(UV) spectral slopes of redshift z~5 Lyman-break galaxies (LBGs). By combining
deep Hubble Space Telescope imaging of the CANDELS and HUDF fields with
ground-based imaging from the UKIDSS Ultra Deep Survey (UDS), we have produced
a large sample of z~5 LBGs spanning an unprecedented factor of >100 in UV
luminosity. Based on this sample we find a clear colour-magnitude relation
(CMR) at z~5, such that the rest-frame UV slopes (beta) of brighter galaxies
are notably redder than their fainter counterparts. We determine that the z~5
CMR is well described by a linear relationship of the form: d beta = (-0.12 +/-
0.02) d Muv, with no clear evidence for a change in CMR slope at faint
magnitudes (i.e. Muv > -18.9). Using the results of detailed simulations we are
able, for the first time, to infer the intrinsic (i.e. free from noise)
variation of galaxy colours around the CMR at z~5. We find significant (12
sigma) evidence for intrinsic colour variation in the sample as a whole. Our
results also demonstrate that the width of the intrinsic UV slope distribution
of z~5 galaxies increases from Delta(beta)=0.1 at Muv=-18 to Delta(beta)=0.4 at
Muv=-21. We suggest that the increasing width of the intrinsic galaxy colour
distribution and the CMR itself are both plausibly explained by a luminosity
independent lower limit of beta=-2.1, combined with an increase in the fraction
of red galaxies in brighter UV-luminosity bins.


title:
Analysis of Asteroid (216) Kleopatra using dynamical and structural
  constraints

abstract:
  Given the spin state by Magnusson (1990), the shape model by Ostro et al.
(2000), and the mass by Descamps et al. (2011), this paper evaluates a
dynamically and structurally stable size of Asteroid (216) Kleopatra. In
particular, we investigate two different failure modes: material shedding from
the surface and structural failure of the internal body. We construct
zero-velocity curves in the vicinity of this asteroid to determine surface
shedding, while we utilize a limit analysis to calculate the lower and upper
bounds of structural failure under the zero-cohesion assumption. Surface
shedding does not occur at the current spin period (5.385 hr) and cannot
directly initiate the formation of the satellites. On the other hand, this body
may be close to structural failure; in particular, the neck may be situated
near a plastic state. In addition, the neck's sensitivity to structural failure
changes as the body size varies. We conclude that plastic deformation has
probably occurred around the neck part in the past. If the true size of this
body is established through additional measurements, this method will provide
strong constraints on the current friction angle for the body.


title: The strange degrees of freedom in QCD at high temperature

abstract:
  We discuss recent results on fluctuations of conserved charges, and their
approach to the hadron resonance gas at temperatures below the chiral crossover
(Tc) as well as to a gas of free quarks at very high temperatures. We will
focus on the strange degrees of freedom and verify that they are consistent
with those of an uncorrelated gas of hadrons for temperatures of T<160 MeV and
that they can be described by a quasi particle model at best for T>2Tc. To
extract this information we use all cumulants of net baryon number and net
strangeness fluctuations and their correlations up to the fourth order. In
particular we propose observables that serve as indicator for the validity of
the hadronic degrees of freedom and show that the partial pressures from
different strangeness sectors agree separately with HRG model predictions.


title: The Borel-Weil theorem for reductive Lie groups

abstract:
  In this manuscript we consider the extent to which an irreducible
representation for a reductive Lie group can be realized as the sheaf cohomolgy
of an equivariant holomorphic line bundle defined on an open invariant
submanifold of a complex flag space. Our main result is the following: suppose
$G_{0}$ is a real reductive group of Harish-Chandra class and let $X$ be the
associated full complex flag space. Suppose $\mathcal{O}_{\lambda}$ is the
sheaf of sections of a $G_{0}$-equivariant holomorphic line bundle on $X$ whose
parameter $\lambda$ (in the usual twisted $\mathcal{D}% $-module context) is
antidominant and regular. Let $S\subseteq X$ be a $G_{0}% $-orbit and suppose
$U\supseteq S$ is the smallest $G_{0}$-invariant open submanifold of $X$ that
contains $S$. From the analytic localization theory of Hecht and Taylor one
knows that there is a nonegative integer $q$ such that the compactly supported
sheaf cohomology groups $H_{\text{c}}^{q}(S,\mathcal{O}_{\lambda}\mid_{S})$
vanish except in degree $q$, in which case
$H_{\text{c}}^{q}(S,\mathcal{O}_{\lambda}\mid_{S})$ is the minimal
globalization of an associated standard Beilinson-Bernstein module. In this
study we show that the $q$-th compactly supported cohomolgy group
$H_{\text{c}}^{q}(U,\mathcal{O}_{\lambda}\mid_{U})$ defines, in a natural way,
a nonzero submodule of $H_{\text{c}}^{q}(S,\mathcal{O}_{\lambda}\mid_{S})$,
which is irreducible (i.e. realizes the unique irreducible submodule of
$H_{\text{c}}^{q}(S,\mathcal{O}_{\lambda}\mid_{S})$) when an associated
algebraic variety is nonsingular. By a tensoring argument, we can show that the
result holds, more generally (for nonsingular Schubert variety), when the
representation $H_{\text{c}}^{q}(S,\mathcal{O}_{\lambda}\mid_{S})$ is what we
call a classifying module.


title: Market models with optimal arbitrage

abstract:
  We construct and study market models admitting optimal arbitrage. We say that
a model admits optimal arbitrage if it is possible, in a zero-interest rate
setting, starting with an initial wealth of 1 and using only positive
portfolios, to superreplicate a constant c>1. The optimal arbitrage strategy is
the strategy for which this constant has the highest possible value. Our
definition of optimal arbitrage is similar to the one in Fernholz and Karatzas
(2010), where optimal relative arbitrage with respect to the market portfolio
is studied. In this work we present a systematic method to construct market
models where the optimal arbitrage strategy exists and is known explicitly. We
then develop several new examples of market models with arbitrage, which are
based on economic agents' views concerning the impossibility of certain events
rather than ad hoc constructions. We also explore the concept of fragility of
arbitrage introduced in Guasoni and Rasonyi (2012), and provide new examples of
arbitrage models which are not fragile in this sense.


title:
The motion law of fronts for scalar reaction-diffusion equations with
  multiple wells : the degenerate case,

abstract:
  We derive a precise motion law for fronts of solutions to scalar
one-dimensional reaction-diffusion equations with equal depth multiple-wells,
in the case the second derivative of the potential vanishes at its minimizers.
We show that, renormalizing time in an algebraic way, the motion of fronts is
governed by a simple system of ordinary differential equations of nearest
neighbor interaction type. These interactions may be either attractive or
repulsive. Our results are not constrained by the possible occurrence of
collisions nor splittings. They present substantial differences with the
results obtained in the case the second derivative does not vanish at the
wells, a case which has been extensively studied in the literature, and where
fronts have been showed to move at exponentially small speed, with motion laws
which are not renormalizable.


title: The fate of fallback matter around newly born compact objects

abstract:
  The presence of fallback disks around young neutron stars has been invoked
over the years to explain a large variety of phenomena. Here we perform a
numerical investigation of the formation of such disks during a supernova
explosion, considering both neutron star (NS) and black hole (BH) remnants.
Using the public code MESA, we compute the angular momentum distribution of the
pre-supernova material, for stars with initial masses M in the range 13 - 40
Msun, initial surface rotational velocities vsurf between 25% and 75% of the
critical velocity, and for metallicities Z of 1%, 10% and 100% of the solar
value. These pre SN models are exploded with energies E varying between 10^{50}
- 3x10^{52} ergs, and the amount of fallback material is computed. We find
that, if magnetic torques play an important role in angular momentum transport,
then fallback disks around NSs, even for low-metallicity main sequence stars,
are not an outcome of SN explosions. Formation of such disks around young NSs
can only happen under the condition of negligible magnetic torques and a
fine-tuned explosion energy. For those stars which leave behind BH remnants,
disk formation is ubiquitous if magnetic fields do not play a strong role;
however, unlike the NS case, even with strong magnetic coupling in the
interior, a disk can form in a large region of the {Z,M,vsurf,E} parameter
space. Together with the compact, hyperaccreting fallback disks widely
discussed in the literature, we identify regions in the above parameter space
which lead to extended, long-lived disks around BHs. We find that the physical
conditions in these disks may be conducive to planet formation, hence leading
to the possible existence of planets orbiting black holes.


title:
Physical properties and transmission spectrum of the WASP-80 planetary
  system from multi-colour photometry

abstract:
  WASP-80 is one of only two systems known to contain a hot Jupiter which
transits its M-dwarf host star. We present eight light curves of one transit
event, obtained simultaneously using two defocussed telescopes. These data were
taken through the Bessell I, Sloan griz and near-infrared JHK passbands. We use
our data to search for opacity-induced changes in the planetary radius, but
find that all values agree with each other. Our data are therefore consistent
with a flat transmission spectrum to within the observational uncertainties. We
also measure an activity index of the host star of log R'_HK=-4.495, meaning
that WASP-80A shows strong chromospheric activity. The non-detection of
starspots implies that, if they exist, they must be small and symmetrically
distributed on the stellar surface. We model all available optical transit
light curves to obtain improved physical properties and orbital ephemerides for
the system.


title: Extreme slowdowns for one-dimensional excited random walks

abstract:
  We study the asymptotics of the probabilities of extreme slowdown events for
transient one-dimensional excited random walks. That is, if $\{X_n\}_{n\geq 0}$
is a transient one-dimensional excited random walk and $T_n = \min\{ k: \, X_k
= n\}$, we study the asymptotics of probabilities of the form $P(X_n \leq
n^\gamma)$ and $P(T_{n^\gamma} \geq n )$ with $\gamma < 1$. We show that there
is an interesting change in the rate of decay of these extreme slowdown
probabilities when $\gamma < 1/2$.


title: Microrheology to probe non-local effects in dense granular flows

abstract:
  A granular material is observed to flow under the Coulomb yield criterion as
soon as this criterion is satisfied in a remote but contiguous region of space.
We investigate this non-local effect using discrete element simulations, in a
geometry similar, in spirit, to the experiment of Reddy et al. (Phys. Rev.
Lett., 106 (2011) 108301): a micro-rheometer is introduced to determine the
influence of a distant shear band on the local rheological behaviour. The
numerical simulations recover the dominant features of this experiment: the
local shear rate is proportional to that in the shear band and decreases
(roughly) exponentially with the distance to the yield conditions. The
numerical results are in quantitative agreement with the predictions of the
non-local rheology proposed by (Phys. Rev. Lett., 111 (2013) 238301) and
derived from a gradient expansion of the rheology $\mu[I]$. The consequences of
these findings for the dynamical mechanisms controlling non-locality are
finally discussed.


title:
All-electrical time-resolved spin generation and spin manipulation in
  n-InGaAs

abstract:
  We demonstrate all-electrical spin generation and subsequent manipulation by
two successive electric field pulses in an n-InGaAs heterostructure in a
time-resolved experiment at zero external magnetic field. The first electric
field pulse along the $[1\bar10]$ crystal axis creates a current induced spin
polarization (CISP) which is oriented in the plane of the sample. The
subsequent electric field pulse along [110] generates a perpendicular magnetic
field pulse leading to a coherent precession of this spin polarization with
2-dimensional electrical control over the final spin orientation. Spin
precession is probed by time-resolved Faraday rotation. We determine the
build-up time of CISP during the first field pulse and extract the spin
dephasing time and internal magnetic field strength during the spin
manipulation pulse.


title:
A Comparative Evaluation of Curriculum Learning with Filtering and
  Boosting

abstract:
  Not all instances in a data set are equally beneficial for inferring a model
of the data. Some instances (such as outliers) are detrimental to inferring a
model of the data. Several machine learning techniques treat instances in a
data set differently during training such as curriculum learning, filtering,
and boosting. However, an automated method for determining how beneficial an
instance is for inferring a model of the data does not exist. In this paper, we
present an automated method that orders the instances in a data set by
complexity based on the their likelihood of being misclassified (instance
hardness). The underlying assumption of this method is that instances with a
high likelihood of being misclassified represent more complex concepts in a
data set. Ordering the instances in a data set allows a learning algorithm to
focus on the most beneficial instances and ignore the detrimental ones. We
compare ordering the instances in a data set in curriculum learning, filtering
and boosting. We find that ordering the instances significantly increases
classification accuracy and that filtering has the largest impact on
classification accuracy. On a set of 52 data sets, ordering the instances
increases the average accuracy from 81% to 84%.


title: Tilings with infinite local complexity

abstract:
  This is a chapter surveying the current state of our understanding of tilings
with infinite local complexity. It is intended to appear in the volume {\em
Directions in Aperiodic Order}, D. Lenz, J. Kellendonk, and J. Savienen, eds.


title:
High Resolution Radio and Optical Observations of the Central Starburst
  in the Low-Metallicity Dwarf Galaxy II Zw 40

abstract:
  The extent to which star formation varies in galaxies with low masses, low
metallicities, and high star formation rate surface densities is not
well-constrained. To gain insight into star formation under these physical
conditions, this paper estimates the ionizing photon fluxes, masses, and ages
for young massive clusters in the central region of II Zw 40 -- the
prototypical low-metallicity dwarf starburst galaxy -- from radio continuum and
optical observations. Discrete, cluster-sized sources only account for half the
total radio continuum emission; the remainder is diffuse. The young (<5 Myr)
central burst has a star formation rate surface density that significantly
exceeds that of the Milky Way. Three of the 13 sources have ionizing photon
fluxes (and thus masses) greater than R136 in 30 Doradus. Although isolating
the effects of galaxy mass and metallicity is difficult, the HII region
luminosity function and the internal extinction in the center of II Zw 40
appear to be primarily driven by a merger-related starburst. The relatively
flat HII region luminosity function may be the result of an increase in ISM
pressure during the merger and the internal extinction is similar to that
generated by the clumpy and porous dust in other starburst galaxies.


title: Maximal Privacy Without Coherence

abstract:
  Privacy lies at the fundament of quantum mechanics. A coherently transmitted
quantum state is inherently private. Remarkably, coherent quantum communication
is not a prerequisite for privacy: there are quantum channels that are too
noisy to transmit any quantum information reliably that can nevertheless send
private classical information. Here, we ask how much private classical
information a channel can transmit if it has little quantum capacity. We
present a class of channels N_d with input dimension d^2, quantum capacity
Q(N_d) <= 1, and private capacity P(N_d) = log d. These channels asymptotically
saturate an interesting inequality P(N) <= (log d_A + Q(N))/2 for any channel N
with input dimension d_A, and capture the essence of privacy stripped of the
confounding influence of coherence.


title: Progress in resolving charge symmetry violation in nucleon structure

abstract:
  Recent work unambiguously resolves the level of charge symmetry violation in
moments of parton distributions using 2+1-flavor lattice QCD. We introduce the
methods used for that analysis by applying them to determine the strong
contribution to the proton-neutron mass difference. We also summarize related
work which reveals that the fraction of baryon spin which is carried by the
quarks is in fact structure-dependent rather than universal across the baryon
octet.


title:
On the velocity space discretization for the Vlasov-Poisson system:
  comparison between Hermite spectral and Particle-in-Cell methods. Part 2:
  fully-implicit scheme

abstract:
  We describe a spectral method for the numerical solution of the
Vlasov-Poisson system where the velocity space is decomposed by means of an
Hermite basis, and the configuration space is discretized via a Fourier
decomposition. The novelty of our approach is an implicit time discretization
that allows exact conservation of charge, momentum and energy. The
computational efficiency and the cost-effectiveness of this method are compared
to the fully-implicit PIC method recently introduced by Markidis and Lapenta
(2011) and Chen et al. (2011). The following examples are discussed: Langmuir
wave, Landau damping, ion-acoustic wave, two-stream instability. The
Fourier-Hermite spectral method can achieve solutions that are several orders
of magnitude more accurate at a fraction of the cost with respect to PIC. This
paper concludes the study presented in Camporeale et al. (2013) where the same
method has been described for a semi-implicit time discretization, and was
compared against an explicit PIC.


title: Exotic Decays of the 125 GeV Higgs Boson

abstract:
  We perform an extensive survey of non-standard Higgs decays that are
consistent with the 125 GeV Higgs-like resonance. Our aim is to motivate a
large set of new experimental analyses on the existing and forthcoming data
from the Large Hadron Collider (LHC). The explicit search for exotic Higgs
decays presents a largely untapped discovery opportunity for the LHC
collaborations, as such decays may be easily missed by other searches. We
emphasize that the Higgs is uniquely sensitive to the potential existence of
new weakly coupled particles and provide a unified discussion of a large class
of both simplified and complete models that give rise to characteristic
patterns of exotic Higgs decays. We assess the status of exotic Higgs decays
after LHC Run 1. In many cases we are able to set new nontrivial constraints by
reinterpreting existing experimental analyses. We point out that improvements
are possible with dedicated analyses and perform some preliminary collider
studies. We prioritize the analyses according to their theoretical motivation
and their experimental feasibility. This document is accompanied by a website
that will be continuously updated with further information:
http://exotichiggs.physics.sunysb.edu.


title: Heterogeneous Programming with Single Operation Multiple Data

abstract:
  Heterogeneity is omnipresent in today's commodity computational systems,
which comprise at least one multi-core Central Processing Unit (CPU) and one
Graphics Processing Unit (GPU). Nonetheless, all this computing power is not
being exploited in mainstream computing, as the programming of these systems
entails many details of the underlying architecture and of its distinct
execution models. Current research on parallel programming is addressing these
issues but, still, the systems' heterogeneity is exposed at language level.
This paper proposes a uniform framework, grounded on the Single Operation
Multiple Data model, for the programming of such heterogeneous systems. The
model is declarative, empowering the compiler to generate code for multiple
architectures from the same source. To this extent, we designed a simple
extension of the Java programming language that embodies the model, and
developed a compiler that generates code for both multi-core CPUs and GPUs. A
performance evaluation attests the validity of the approach that, despite being
based on a simple programming model, is able to deliver performance gains on
par with hand-tuned data parallel multi-threaded Java applications.


title: On autoequivalences of the (\infty, 1)-category of \infty-operads

abstract:
  We study the (\infty, 1)-category of autoequivalences of \infty-operads.
Using techniques introduced by To\"en, Lurie, and Barwick and Schommer-Pries,
we prove that this (\infty, 1)-category is a contractible \infty-groupoid. Our
calculation is based on the model of complete dendroidal Segal spaces
introduced by Cisinski and Moerdijk. Similarly, we prove that the (\infty,
1)-category of autoequivalences of non-symmetric \infty-operads is the discrete
monoidal category associated to Z/2Z. We also include a computation of the
(\infty, 1)-category of autoequivalences of (\infty, n)-categories based on
Rezk's \Theta_n-spaces.


title:
Geodesic Completeness for Sobolev Metrics on the Space of Immersed Plane
  Curves

abstract:
  We study properties of Sobolev-type metrics on the space of immersed plane
curves. We show that the geodesic equation for Sobolev-type metrics with
constant coefficients of order 2 and higher is globally well-posed for smooth
initial data as well as initial data in certain Sobolev spaces. Thus the space
of closed plane curves equipped with such a metric is geodesically complete. We
find lower bounds for the geodesic distance in terms of curvature and its
derivatives.


title:
SDSS-III Baryon Oscillation Spectroscopic Survey: Analysis of Potential
  Systematics in Fitting of Baryon Acoustic Feature

abstract:
  Extraction of the Baryon Acoustic Oscillations (BAO) to percent level
accuracy is challenging and demands an understanding of many potential
systematic to an accuracy well below 1 per cent, in order ensure that they do
not combine significantly when compared to statistical error of the BAO
measurement. Sloan Digital Sky Survey (SDSS)-III Baryon Oscillation
Spectroscopic Survey (BOSS) SDSS Data Release Eleven (DR11) reaches a distance
measurement with $\sim 1\%$ statistical error and this prompts an extensive
search for all possible sub-percent level systematic errors which could be
safely ignored previously. In this paper, we analyze the potential systematics
in BAO fitting methodology using mocks and data from BOSS DR10 and DR11. We
demonstrate the robustness of the fiducial multipole fitting methodology to be
at $0.1\%-0.2\%$ level with a wide range of tests in mock galaxy catalogs pre-
and post-reconstruction. We also find the DR10 and DR11 data from BOSS to be
robust against changes in methodology at similar level. This systematic error
budget is incorporated into the the error budget of Baryon Oscillation
Spectroscopic Survey (BOSS) DR10 and DR11 BAO measurements. Of the wide range
of changes we have investigated, we find that when fitting pre-reconstructed
data or mocks, the following changes have the largest effect on the best fit
values of distance measurements both parallel and perpendicular to the line of
sight: (a) Changes in non-linear correlation function template; (b) Changes in
fitting range of the correlation function; (c) Changes to the non-linear
damping model parameters. The priors applied do not matter in the estimates of
the fitted errors as long as we restrict ourselves to physically meaningful
fitting regions.[abridged]


title:
An analysis of the R\"uschendorf transform - with a view towards Sklar's
  Theorem

abstract:
  In many applications including financial risk measurement, copulas have shown
to be a powerful building block to reflect multivariate dependence between
several random variables including the mapping of tail dependencies.
  A famous key result in this field is Sklar's Theorem. Meanwhile, there exist
several approaches to prove Sklar's Theorem in its full generality. An elegant
probabilistic proof was provided by L. R\"{u}schendorf. To this end he
implemented a certain "distributional transform" which naturally transforms an
arbitrary distribution function $F$ to a flexible parameter-dependent function
which exhibits exactly the same jump size as $F$.
  By using some real analysis and measure theory only (without involving the
use of a given probability measure) we expand into the underlying rich
structure of the distributional transform. Based on derived results from this
analysis (such as Proposition 2.5 and Theorem 2.12) including a strong and
frequent use of the right quantile function, we revisit R\"{u}schendorf's proof
of Sklar's theorem and provide some supplementing observations including a
further characterisation of distribution functions (Remark 2.3) and a strict
mathematical description of their "flat pieces" (Corollary 2.8 and Remark 2.9).


title: A Refined Waring Problem for Finite Simple Groups

abstract:
  Let v and w be nontrivial words in two free groups. We prove that, for all
sufficiently large finite non-abelian simple groups G, there exist subsets C of
v(G) and D of w(G) of size such that every element of G can be realized in at
least one way as the product of an element of C and an element of D and the
average number of such representations is O(log |G|). In particular, if w is a
fixed nontrivial word and G is a sufficiently large finite non-abelian simple
group, then w(G) contains a thin base of order 2. This is a non-abelian
analogue of a result of Van Vu for the classical Waring problem. Further
results concerning thin bases of G of order 2 are established for any finite
group and for any compact Lie group G.


title: Chiral perturbation theory for gradient flow observables

abstract:
  We construct the next-to-leading order chiral lagrangian for scalar and
pseudo-scalar densities defined using the gradient flow. We calculate the
chiral condensate and the pion decay constant to this order from operators at
positive flow time, and confirm results obtained earlier in the chiral limit.
We also calculate the quark mass dependence of the scales $t_0$ and $w_0$
defined from the scalar gluon density and find that nonanalytic terms in the
quark mass only enter at next-to-next-to-leading order.


title: Mass distributions marginalized over per-event errors

abstract:
  We present generalizations of the Crystal-Ball function to describe mass
peaks in which the per-event mass resolution is unknown and marginalized over.
The presented probability density functions are tested using a series of toy-MC
samples generated with Pythia and smeared with different amounts of multiple
scattering and for different detector resolutions.


title: Defect Networks and Supersymmetric Loop Operators

abstract:
  We consider topological defect networks with junctions in $A_{N-1}$ Toda CFT
and the connection to supersymmetric loop operators in $\mathcal{N} = 2$
theories of class S on a four-sphere. Correlation functions in the presence of
topological defect networks are computed by exploiting the monodromy of
conformal blocks, generalising the notion of a Verlinde operator. Concentrating
on a class of topological defects in $A_2$ Toda theory, we find that the
Verlinde operators generate an algebra whose structure is determined by a set
of generalised skein relations. These relations encode the representation
theory of a quantum group. In the second half of the paper, we explore the
dictionary between topological defect networks and supersymmetric loop
operators in the $\mathcal{N}=2^*$ star theory by comparing to exact
localisation computations. In this context, the the generalised skein relations
are related to the operator product expansion of loop operators.


title:
Efficient Performance Evaluation of the Generalized Shiryaev--Roberts
  Detection Procedure in a Multi-Cyclic Setup

abstract:
  We propose a numerical method to evaluate the performance of the emerging
Generalized Shiryaev--Roberts (GSR) change-point detection procedure in a
"minimax-ish" multi-cyclic setup where the procedure of choice is applied
repetitively (cyclically) and the change is assumed to take place at an unknown
time moment in a distant-future stationary regime. Specifically, the proposed
method is based on the integral-equations approach and uses the collocation
technique with the basis functions chosen so as to exploit a certain
change-of-measure identity and the GSR detection statistic's unique martingale
property. As a result, the method's accuracy and robustness improve, as does
its efficiency since using the change-of-measure ploy the Average Run Length
(ARL) to false alarm and the Stationary Average Detection Delay (STADD) are
computed simultaneously. We show that the method's rate of convergence is
quadratic and supply a tight upperbound on its error. We conclude with a case
study and confirm experimentally that the proposed method's accuracy and rate
of convergence are robust with respect to three factors: (a) partition fineness
(coarse vs. fine), (b) change magnitude (faint vs. contrast), and (c) the level
of the ARL to false alarm (low vs. high). Since the method is designed not
restricted to a particular data distribution or to a specific value of the GSR
detection statistic's headstart, this work may help gain greater insight into
the characteristics of the GSR procedure and aid a practitioner to design the
GSR procedure as needed while fully utilizing its potential.


title: Extracting jet transport coefficient from jet quenching at RHIC and LHC

abstract:
  Within five different approaches to parton propagation and energy loss in
dense matter, a phenomenological study of experimental data on suppression of
large $p_T$ single inclusive hadrons in heavy-ion collisions at both RHIC and
LHC was carried out. The evolution of bulk medium used in the study for parton
propagation was given by 2+1D or 3+1D hydrodynamic models which are also
constrained by experimental data on bulk hadron spectra. Values for the jet
transport parameter $\hat q$ at the center of the most central heavy-ion
collisions are extracted or calculated within each model, with parameters for
the medium properties that are constrained by experimental data on the hadron
suppression factor $R_{AA}$. For a quark with initial energy of 10 GeV we find
that $\hat q\approx 1.2 \pm 0.3$ GeV$^2$/fm at an initial time $\tau_0=0.6$
fm/$c$ in Au+Au collisions at $\sqrt{s}=200$ GeV/n and $\hat q\approx 1.9 \pm
0.7 $ GeV$^2$/fm in Pb+Pb collisions at $\sqrt{s}=2.76 $ TeV/n. Compared to
earlier studies, these represent significant convergence on values of the
extracted jet transport parameter, reflecting recent advances in theory and the
availability of new experiment data from the LHC.


title:
High-Order Fully General-Relativistic Hydrodynamics: new Approaches and
  Tests

abstract:
  We present a new approach for achieving high-order convergence in fully
general-relativistic hydrodynamic simulations. The approach is implemented in
WhiskyTHC, a new code that makes use of state-of-the-art numerical schemes and
was key in achieving, for the first time, higher than second-order convergence
in the calculation of the gravitational radiation from inspiraling binary
neutron stars Radice et al. (2013). Here, we give a detailed description of the
algorithms employed and present results obtained for a series of classical
tests involving isolated neutron stars. In addition, using the
gravitational-wave emission from the late inspiral and merger of binary neutron
stars, we make a detailed comparison between the results obtained with the new
code and those obtained when using standard second-order schemes commonly
employed for matter simulations in numerical relativity. We find that even at
moderate resolutions and for binaries with large compactness, the phase
accuracy is improved by a factor 50 or more.


title: Single Past Null Geodesic in the Lemaitre-Tolman-Bondi Cosmology

abstract:
  This work provides a general discussion of the spatially inhomogeneous
Lema\^itre-Tolman-Bondi (LTB) cosmology, as well as its basic properties and
many useful relevant quantities, such as the cosmological distances. We apply
the concept of the single null geodesic to produce some simple analytical
solutions for observational quantities such as the redshift. As an application
of the single null geodesic technique, we carry out a fractal approach to the
parabolic LTB model, comparing it to the spatially homogeneous Einstein-de
Sitter cosmology. The results obtained indicate that the standard model, in
this case represented by the Einstein-de Sitter cosmology, can be equivalently
described by a fractal distribution of matter, as we found that different
single fractal dimensions describe different scale ranges of the parabolic LTB
matter distribution. It is shown that at large ranges the parabolic LTB model
with fractal dimension equal to 0.5 approximates the matter distribution of the
Einstein-de Sitter universe.


title: Beam-beam compensation studies in the Tevatron with electron lenses

abstract:
  At the Fermilab Tevatron collider, we studied the feasibility of suppressing
the antiproton head-on beam-beam tune spread using a magnetically confined
5-keV electron beam with Gaussian transverse profile overlapping with the
circulating beam. When electron cooling of antiprotons was applied in regular
Tevatron operations, the nonlinear head-on beam-beam effect on antiprotons was
small. Therefore, we first focused on the operational aspects, such as beam
alignment and stability, and on fundamental observations of tune shifts, tune
spreads, lifetimes, and emittances. We also attempted two special collider
stores with only 3 proton bunches colliding with 3 antiproton bunches, to
suppress long-range forces and enhance head-on effects. We present here the
results of this study and a comparison between numerical simulations and
observations. These results contributed to the application of this compensation
concept to RHIC at Brookhaven.


title:
Measurements of the effect of collisions on transverse beam halo
  diffusion in the Tevatron and in the LHC

abstract:
  Beam-beam forces and collision optics can strongly affect beam lifetime,
dynamic aperture, and halo formation in particle colliders. Extensive
analytical and numerical simulations are carried out in the design and
operational stage of a machine to quantify these effects, but experimental data
is scarce. The technique of small-step collimator scans was applied to the
Fermilab Tevatron collider and to the CERN Large Hadron Collider to study the
effect of collisions on transverse beam halo dynamics. We describe the
technique and present a summary of the first results on the dependence of the
halo diffusion coefficient on betatron amplitude in the Tevatron and in the
LHC.


title: Symmetric matrices, orthogonal Lie algebras, and Lie-Yamaguti algebras

abstract:
  On the set H_n(K) of symmetric n by n matrices over the field K we can define
various binary and ternary products which endow it with the structure of a
Jordan algebra or a Lie or Jordan triple system. All these non-associative
structures have the orthogonal Lie algebra so(n,K) as derivation algebra. This
gives an embedding of so(n,K) into so(N,K) for N = n(n+1)/2 - 1. We obtain a
sequence of reductive pairs (so(N,K), so(n,K)) that provides a family of
irreducible Lie-Yamaguti algebras. In this paper we explain in detail the
construction of these Lie-Yamaguti algebras. In the cases n < 5, we use
computer algebra to determine the polynomial identities of degree < 7; we also
study the identities relating the bilinear Lie-Yamaguti product with the
trilinear product obtained from the Jordan triple product.


title: Ergodic Action Semigroups which Was Inspired by Pesin's Theory

abstract:
  By benefit of Pesin's method to prove ergodicity with respect to Lebesgue
measure for ordinary dynamical systems, we conclude ergodicity (resp.
term-ergodicity) for some action semigroups with respect to volume measure
(resp. quasi measure). To this aim, the main tool is the theory of local
ergodicity.


title:
Detection of coherent beam-beam modes with digitized beam position
  monitor signals

abstract:
  A system for bunch-by-bunch detection of transverse proton and antiproton
coherent oscillations in the Fermilab Tevatron collider is described. It is
based on the signal from a single beam-position monitor located in a region of
the ring with large amplitude functions. The signal is digitized over a large
number of turns and Fourier-analyzed offline with a dedicated algorithm. To
enhance the signal, band-limited noise is applied to the beam for about 1 s.
This excitation does not adversely affect the circulating beams even at high
luminosities. The device has a response time of a few seconds, a frequency
resolution of $1.6\times 10^{-5}$ in fractional tune, and it is sensitive to
oscillation amplitudes of 60 nm. It complements Schottky detectors as a
diagnostic tool for tunes, tune spreads, and beam-beam effects. Measurements of
coherent mode spectra are presented and compared with models of beam-beam
oscillations.


title: Update on the 2+1+1 flavor QCD equation of state with HISQ

abstract:
  We present recent results on the QCD equation of state with 2+1+1 flavors of
highly improved staggered quarks (HISQ). We focus on three sets of ensembles
with temporal extent 6, 8 and 10, that reach up to temperatures of 967, 725 and
580 MeV, respectively. The strange and charm quark masses are tuned to the
physical values and the light quarks mass is set to one fifth of the strange.
This corresponds to a Goldstone pion of about 300 MeV.


title: The Highly Connected Matroids in Minor-closed Classes

abstract:
  For any minor-closed class of matroids over a fixed finite field, we state an
exact structural characterization for the sufficiently connected matroids in
the class. We also state a number of conjectures that might be approachable
using the structural characterization.


title: A Roadmap for Canadian Submillimetre Astronomy

abstract:
  We survey the present landscape in submillimetre astronomy for Canada and
describe a plan for continued engagement in observational facilities to ~2020.
Building on Canada's decadal Long Range Plan process, we emphasize that
continued involvement in a large, single-dish facility is crucial given
Canada's substantial investment in ALMA and numerous PI-led submillimetre
experiments. In particular, we recommend: i) an extension of Canadian
participation in the JCMT until at least the unique JCMT Legacy Survey program
is able to realize the full scientific potential provided by the world-leading
SCUBA-2 instrument; and ii) involvement of the entire Canadian community in
CCAT, with a large enough share in the partnership for Canadian astronomers to
participate at all levels of the facility. We further recommend continued
participation in ALMA development, involvement in many focused PI-led
submillimetre experiments, and partnership in SPICA.


title:
Control protocol of finite dimensional quantum systems using alternating
  square pulse

abstract:
  Control protocol to drive finite dimensional quantum systems to an arbitrary
target state using square pulses is proposed explicitly. It is a multi-cycle
control process and in each cycle we apply square pulses to cause single or a
few transitions between energy levels. Systems with equal energy gaps except
the first one, four dimensional system with equal first and third energy gaps
and different second energy gap, and systems with all equal energy gaps of
dimension three, are investigated in detail. The control parameters, the
interaction time between systems and control fields and free evolution times
between cycles, are connected with the probability amplitudes of target states
via trigonometric functions and are determined analytically.


title: Stability of multivacancies in graphene

abstract:
  The stability of graphene multivacancy systems is studied using Density
Functional Theory (DFT) calculations. This work describes the evolution of the
energy of formation per carbon atom for zigzag and armchair complementary
figures -i.e. the figure formed by the carbon atoms extracted from graphene to
form the vacancy-. Multivacancy systems formed when armchair complementary
figures are removed are more stable for higher orders (>5) in comparison with
the zigzag ones. The case of the construction of a 6-order vacancy from a
5-order one (branch-like) is discussed with the dependence on the place where
the extra carbon atom is removed from graphene. The stability of multivacancy
systems could be explained through the relative positions of the pentagonal
rings present in the resulting defected graphene structure, as the more
relevant factor. Other secondary factors that affect the stability of a
graphene multivacancy system are the dangling bonds magnetic arrangements and
their steric hindrance.


title: Essential surfaces in highly twisted link complements

abstract:
  We prove that in the complement of a highly twisted link, all closed,
essential, meridionally incompressible surfaces must have high genus. The genus
bound is proportional to the number of crossings per twist region. A similar
result holds for surfaces with meridional boundary: such a surface either has
large negative Euler characteristic, or is an n-punctured sphere visible in the
diagram.


title:
Cannon-Thurston maps for Coxeter groups including affine special
  subgroups

abstract:
  For a Coxeter group $W$ we have an associating bi-linear form $B$ on a real
vector space. We assume that $B$ has the signature $(n-1,1)$. In this case we
have the Cannon-Thurston map for $W$, that is, a $W$-equivariant continuous
surjection from the Gromov boundary of $W$ to the limit set of $W$. We focus on
the case where Coxeter groups contain affine special subgroups.


title: Model spaces: a survey

abstract:
  This is a brief and gentle introduction, aimed at graduate students, to the
subject of model subspaces of the Hardy space.


title: A Short Proof of Stirling's Formula

abstract:
  By changing variables in a suitable way and using dominated convergence
methods, this note gives a short proof of Stirling's formula and its
refinement.


title: A Non-Pythagorean Musical Scale Based on Logarithms

abstract:
  A new musical scale devised by the author, based on natural logarithms, is
described. Most of the logarithmic pitches bear no correspondence to the twelve
tones of the ancient tuning system attributed to Pythagoras, based on ratios of
whole numbers, nor to the chromatic tones of scales in equal temperament used
widely in the modern era. Logarithms obey a special arithmetic compared to
whole and rational numbers, which can be heard in beat frequencies between
tones of the scale, suggesting extended harmonic possibilities by incorporating
the beat frequencies into compositions. The author uses the broad term
"non-Pythagorean" to describe the logarithmic musical scale, as the ratios of
pitches are usually irrational numbers.


title: Efficient Online Bootstrapping for Large Scale Learning

abstract:
  Bootstrapping is a useful technique for estimating the uncertainty of a
predictor, for example, confidence intervals for prediction. It is typically
used on small to moderate sized datasets, due to its high computation cost.
This work describes a highly scalable online bootstrapping strategy,
implemented inside Vowpal Wabbit, that is several times faster than traditional
strategies. Our experiments indicate that, in addition to providing a black
box-like method for estimating uncertainty, our implementation of online
bootstrapping may also help to train models with better prediction performance
due to model averaging.


title:
Mapping between the classical and pseudoclassical models of a
  relativistic spinning particle in external bosonic and fermionic fields. I

abstract:
  The problem on mapping between two Lagrangian descriptions (using a commuting
$c$-number spinor $\psi_{\alpha}$ or anticommuting pseudovector $\xi_{\mu}$ and
pseudoscalar $\xi_5$ variables) of the spin degrees of freedom of a color
spinning massive particle interacting with background non-Abelian gauge field,
is considered. A general analysis of the mapping between a pair of {\it
Majorana} spinors $(\psi_{\alpha},\theta_{\alpha})$ ($\theta_{\alpha}$ is some
auxiliary anticommuting spinor) and a real anticommuting tensor aggregate
$(S,V_{\mu},\!\,^{\ast}T_{\mu \nu},A_{\mu},P)$, is presented. A complete system
of bilinear relations between the tensor quantities, is obtained. The analysis
we have given is used for the above problem of the equivalence of two different
ways of describing the spin degrees of freedom of the relativistic particle.
The mapping of the kinetic term $(i\hbar/2)(\bar{\theta}\theta)
(\dot{\bar{\psi}}\psi-\bar{\psi}\dot{\psi})$, the term
$(1/e)(\bar{\theta}\theta)\dot{x}_{\mu}(\bar{\psi}\gamma^{\mu}\psi)$ that
provides a couple of the spinning variable $\psi$ and the particle velocity
$\dot{x}_{\mu}$, and the interaction term
$\hbar(\bar{\theta}\theta)Q^{a}F_{\mu\nu}^a (\bar{\psi}\sigma^{\mu\nu}\psi)$
with an external non-Abelian gauge field, are considered in detail. In the
former case a corresponding system of bilinear identities including both the
tensor variables and their derivatives
$(\dot{S},\dot{V}_{\mu},\!\,^{\ast}\dot{T}_{\mu\nu},\dot{A}_{\mu}, \dot{P})$,
is defined. A detailed analysis of the local bosonic symmetry of the Lagrangian
with the commuting spinor $\psi_{\alpha}$, is carried out. A connection of this
symmetry with the local SUSY transformation of the Lagrangian containing
anticommuting pseudovector and pseudoscalar variables, is considered.


title:
Contextually Supervised Source Separation with Application to Energy
  Disaggregation

abstract:
  We propose a new framework for single-channel source separation that lies
between the fully supervised and unsupervised setting. Instead of supervision,
we provide input features for each source signal and use convex methods to
estimate the correlations between these features and the unobserved signal
decomposition. We analyze the case of $\ell_2$ loss theoretically and show that
recovery of the signal components depends only on cross-correlation between
features for different signals, not on correlations between features for the
same signal. Contextually supervised source separation is a natural fit for
domains with large amounts of data but no explicit supervision; our motivating
application is energy disaggregation of hourly smart meter data (the separation
of whole-home power signals into different energy uses). Here we apply
contextual supervision to disaggregate the energy usage of thousands homes over
four years, a significantly larger scale than previously published efforts, and
demonstrate on synthetic data that our method outperforms the unsupervised
approach.


title:
12.2-GHz methanol maser MMB follow-up catalogue - III. Longitude range
  10 to 20 degrees

abstract:
  We present the third instalment of a series of catalogues presenting 12.2-GHz
methanol maser observations made towards each of the 6.7-GHz methanol masers
detected in the Methanol Multibeam (MMB) Survey. The current portion of the
catalogue includes the Galactic longitude region 10 to 20 degrees, where we
detect 47 12.2-GHz methanol masers towards 99 6.7-GHz targets. We compare the
occurrence of 12.2-GHz methanol masers with water maser emission, for which all
6.7-GHz methanol masers in the 6 to 20 degrees longitude range have now been
searched. We suggest that the water masers follow a more complicated
evolutionary scenario than has been found for the methanol and OH masers,
likely due to their different pumping mechanisms. Comparisons of the 6.7-GHz
methanol to OH maser peak flux density ratio and the luminosity of the
associated 12.2-GHz sources suggests that the 12.2-GHz maser luminosity begins
to decline around the time that an OH maser becomes detectable.


title:
Gaussian-modulated coherent-state measurement-device-independent quantum
  key distribution

abstract:
  Measurement-device-independent quantum key distribution (MDI-QKD), leaving
the detection procedure to the third partner and thus being immune to all
detector side-channel attacks, is very promising for the construction of
high-security quantum information networks. We propose a scheme to implement
MDI-QKD, but with continuous variables instead of discrete ones, i.e., with the
source of Gaussian-modulated coherent states, based on the principle of
continuous-variable entanglement swapping. This protocol not only can be
implemented with current telecom components but also has high key rates
compared to its discrete counterpart; thus it will be highly compatible with
quantum networks.


title:
Magneto-transport characteristics of a 2D electron system driven to
  negative magneto-conductivity by microwave photoexcitation

abstract:
  Negative diagonal magneto-conductivity/resistivity is a spectacular- and
thought provoking- property of driven, far-from-equilibrium, low dimensional
electronic systems. The physical response of this exotic electronic state is
not yet fully understood since it is rarely encountered in experiment. The
microwave-radiation-induced zero-resistance state in the high mobility
GaAs/AlGaAs 2D electron system is believed to be an example where negative
magneto-conductivity/resistivity is responsible for the observed phenomena.
Here, we examine the magneto-transport characteristics of this negative
conductivity/resistivity state in the microwave photo-excited two-dimensional
electron system (2DES) through a numerical solution of the associated boundary
value problem. The results suggest, surprisingly, that a bare negative diagonal
conductivity/resistivity state in the 2DES under photo-excitation should yield
a positive diagonal resistance with a concomitant sign reversal in the Hall
voltage.


title: Mixing in thermally stratified nonlinear spin-up with sources and sinks

abstract:
  Stratified spin-up experiments in enclosed cylinders have reported the
presence of small pockets of well-mixed fluids but quantitative measurements of
the mixedness of the fluid has been lacking. Previous numerical simulations
have not addressed these measurements. Here we present numerical simulations
that address how the combined effect of spin-up and thermal boundary conditions
enhances or hinders mixing of a fluid in a cylinder. Measurements of efficiency
of mixing are based on the variance of temperature and explained in terms of
the potential energy available. The numerical simulations of the Navier--Stokes
equations for the problem with different sets of thermal boundary conditions at
the horizontal walls helped shed some light on the physical mechanisms of
mixing, for which a clear explanation was lacking.


title:
Dephasing in single-electron generation due to environmental noise
  probed by Hong Ou Mandel interferometry

abstract:
  We consider the effect of dephasing on a quantum dot which injects single
electrons on a chiral edge channel of the quantum Hall effect. Dephasing is
described by the coupling of the dot to a bosonic bath which represents the
electromagnetic environment. Using the input-output formalism of quantum
optics, we derive the density matrix of the edge degrees of freedom. Results
are illustrated by computing the zero frequency current-current correlations
when two such single electron emitters achieve a collision at the location of a
quantum point contact, in the same spirit as the Hong Ou Mandel experiment of
quantum optics. Such correlations are directly linked to the quantum mechanical
purity. We show that as observed in a recent experiment, the effect of
dephasing leads to a non-vanishing of the Hong Ou Mandel dip when the time
delay between the two electron wave packets is zero. Generalizations to time
filtered wave packets as well as to asymmetric, detuned injection between
opposite edges are obtained.


title:
Hrushovski's Algorithm for Computing the Galois Group of a Linear
  Differential Equation

abstract:
  We present a detailed and simplified version of Hrushovski's algorithm that
determines the Galois group of a linear differential equation. There are three
major ingredients in this algorithm. The first is to look for a degree bound
for proto-Galois groups, which enables one to compute one of them. The second
is to determine the identity component of the Galois group that is the pullback
of a torus to the proto-Galois group. The third is to recover the Galois group
from its identity component and a finite Galois group.


title:
Irreducible $p$-local compact groups I. The structure of $p$-local
  compact groups of rank $1$

abstract:
  Let $p$ be a fixed prime number. The main purpose of this paper is to
introduce the notion of \textit{irreducible} $p$-local compact group, which
provides a first reduction towards a classification of all $p$-local compact
groups. In order to test this idea, in this note we describe all $p$-local
compact groups of rank $1$ in terms of this notion.


title: 5-mg suspended mirror driven by measurement-induced back-action

abstract:
  Quantum mechanics predicts superposition of position states even for
macroscopic objects. Recently, the use of a quasi-freely suspended mirror
combined with laser was proposed to prepare such states, by M\"uller-Ebhardt et
al. [Phys.Rev.Lett.100, 013601 (2008)]. One of the key milestones towards this
goal is the preparation of the mechanical oscillator mainly driven by quantum
back-action, which identifies the connection between the object and quantumness
of the light. Here, we describe development of a suspended 5-mg mirror driven
by quantum back-action larger than thermal fluctuating force by a factor of
1.4$\pm$0.2 at 325 Hz,which is confirmed by using a triangular optical cavity.


title:
Statistical and Systematic Errors in Measurement of Weak-Lensing
  Minkowski Functionals: Application to Canada-France-Hawaii Lensing Survey

abstract:
  The measurement of cosmic shear using weak gravitational lensing is a
challenging task that involves a number of complicated procedures. We study in
detail the systematic errors in the measurement of weak lensing Minkowski
Functionals (MFs). Specifically, we focus on systematics associated with galaxy
shape measurements, photometric redshift errors, and shear calibration
correction. We first generate mock weak-lensing catalogs that directly
incorporate the actual observational characteristics of the
Canada-France-Hawaii Lensing Survey (CFHTLenS). We then perform a Fisher
analysis using the large set of mock catalogs for various cosmological models.
We find that the statistical error associated with the observational effects
degrades the cosmological parameter constraints by a factor of a few. The
Subaru Hyper Suprime-Cam (HSC) survey with a sky coverage of ~1400 deg2 will
constrain the dark energy equation of the state parameter with an error of
Delta w_0 ~ 0.25 by the lensing MFs alone, but biases induced by the
systematics can be comparable to the 1-sigma error. We conclude that the
lensing MFs are powerful statistics beyond the two-point statistics, only if
well-calibrated measurement of both the redshifts and the shapes of source
galaxies is performed. Finally, we analyze the CFHTLenS data to explore the
ability of the MFs to break degeneracies between a few cosmological parameters.
Using a combined analysis of the MFs and the shear correlation function, we
derive the matter density Omega_m0= 0.256+0.054-0.046.


title:
Evaluation of Plane Detection with RANSAC According to Density of 3D
  Point Clouds

abstract:
  We have implemented a method that detects planar regions from 3D scan data
using Random Sample Consensus (RANSAC) algorithm to address the issue of a
trade-off between the scanning speed and the point density of 3D scanning.
However, the limitation of the implemented method has not been clear yet. In
this paper, we conducted an additional experiment to evaluate the implemented
method by changing its parameter and environments in both high and low point
density data. As a result, the number of detected planes in high point density
data was different from that in low point density data with the same parameter
value.


title: The D_4 flavor symmery in 3-3-1 model with neutral leptons

abstract:
  We construct a $D_4$ flavor model based on SU(3)_C X SU}(3_L X U(1)_X gauge
symmetry responsible for fermion masses and mixings. The neutrinos get small
masses from antisextets which are in a singlet and a doublet under $D_4$. If
the D_4 symmetry is violated as perturbation by a Higgs triplet under SU(3)_L
and lying in {1}''' of D_4, the corresponding neutrino mass mixing matrix gets
the most general form. In this case, the model can fit the experimental data in
2012 on neutrino masses and mixing. Our results show that the neutrino masses
are naturally small and a little deviation from the tribimaximal neutrino
mixing form can be realized. The quark masses and mixing matrix are also
discussed. In the model under consideration, the CKM matrix can be different
from the unit matrix. The scalar potential of the model is more simpler than
those of the model based on $S_3$ and $S_4$. Assignation of VEVs to antisextets
leads to the mixing of the new gauge bosons and those in the Standard Model.
The mixing in the charged gauge bosons as well as the neutral gauge boson is
considered.


title:
SybilBelief: A Semi-supervised Learning Approach for Structure-based
  Sybil Detection

abstract:
  Sybil attacks are a fundamental threat to the security of distributed
systems. Recently, there has been a growing interest in leveraging social
networks to mitigate Sybil attacks. However, the existing approaches suffer
from one or more drawbacks, including bootstrapping from either only known
benign or known Sybil nodes, failing to tolerate noise in their prior knowledge
about known benign or Sybil nodes, and being not scalable.
  In this work, we aim to overcome these drawbacks. Towards this goal, we
introduce SybilBelief, a semi-supervised learning framework, to detect Sybil
nodes. SybilBelief takes a social network of the nodes in the system, a small
set of known benign nodes, and, optionally, a small set of known Sybils as
input. Then SybilBelief propagates the label information from the known benign
and/or Sybil nodes to the remaining nodes in the system.
  We evaluate SybilBelief using both synthetic and real world social network
topologies. We show that SybilBelief is able to accurately identify Sybil nodes
with low false positive rates and low false negative rates. SybilBelief is
resilient to noise in our prior knowledge about known benign and Sybil nodes.
Moreover, SybilBelief performs orders of magnitudes better than existing Sybil
classification mechanisms and significantly better than existing Sybil ranking
mechanisms.


title:
Double injection, resonant-tunneling recombination, and current-voltage
  characteristics in double-graphene-layer structures

abstract:
  We evaluate the effect of the recombination associated with interlayer
transitions in ungated and gated double-graphene-layer (GL) structures on the
injection of electrons and holes. Using the proposed model, we derive
analytical expressions for the spatial distributions of the electron and hole
Fermi energies and the energy gap between the Dirac points in GLs as well as
their dependences on the bias and gate voltages. The current-voltage
characteristics are calculated as well. % The model is based on hydrodynamic
equations for the electron and hole transport in GLs under the self-consistent
electric field. It is shown that in undoped double-GL structures with weak
scattering of electrons and holes on disorder, the Fermi energies and the
energy gap are virtually constant across the main portions of GLs, although
their values strongly depend on the voltages and recombination parameters. In
contrast, the electron and hole scattering on disorder lead to substantial
nonuniformities. The resonant inter-GL tunneling enables N-shaped
current-voltage characteristics provided that GLs are sufficiently short. The
width of the current maxima is much larger than the broadening of the tunneling
resonance. In the double-GL structures with relatively long GLs the N-shaped
characteristics transform into the Z-shaped characteristics. % The obtained
results are in line with the experimental observations \cite{1} and might be
useful for design and optimization of different devices based on double-GL
structures, including field-effect transistors and terahertz lasers.


title: Schr\"odinger representations from the viewpoint of monoidal categories

abstract:
  The Drinfel'd double D(A) of a finite-dimensional Hopf algebra A is a Hopf
algebraic counterpart of the monoidal center construction. Majid introduced an
important representation of the Drinfel'd double, which he called the
Schr\"odinger representation. We study this representation from the viewpoint
of the theory of monoidal categories. One of our main results is as follows: If
two finite-dimensional Hopf algebras A and B over a field k are monoidally
Morita equivalent, i.e., there exists an equivalence F from the module category
over A to the module category over B of k-linear monoidal categories, then the
equivalence between the module categories over D(A) and D(B) induced by F
preserves the Schr\"odinger representation.
  As an application, we construct a family of invariants of finite-dimensional
Hopf algebras under the monoidal Morita equivalence. This family is
parameterized by braids. The invariant associated to a braid b is, roughly
speaking, defined by "coloring'' the closure of b by the Schr\"odinger
representation. We investigate what algebraic properties this family have and,
in particular, show that the invariant associated to a certain braid closely
relates to the number of irreducible representations.


title: Sharp maximal $L^p$-estimates for martingales

abstract:
  Let $X$ be a supermartingale starting from $0$ which has only nonnegative
jumps. For each $0<p<1$ we determine the best constants $c_p$, $C_p$ and
$\mathfrak{c}_p$ such that $$ \,\,\,\,\sup_{t\geq
0}\left|\left|X_t\right|\right|_p\leq C_p\left|\left|-\inf_{t\geq
0}X_t\right|\right|_p,$$ $$ \,\,||\sup_{t\geq 0}X_t||_p\leq
c_p\left|\left|-\inf_{t\geq 0}X_t\right|\right|_p$$ and $$ ||\sup_{t\geq
0}|X_t|\;||_p\leq \mathfrak{c}_p\left|\left|-\inf_{t\geq
0}X_t\right|\right|_p.$$ The estimates are shown to be sharp if $X$ is assumed
to be a stopped one-dimensional Brownian motion. The inequalities are deduced
from the existence of special functions, enjoying certain majorization and
convexity-type properties. Some applications concerning harmonic functions on
Euclidean domains are indicated.


title:
NuSTAR and Swift observations of the fast rotating magnetized white
  dwarf AE Aquarii

abstract:
  AE Aquarii is a cataclysmic variable with the fastest known rotating
magnetized white dwarf (P_spin = 33.08 s). Compared to many intermediate
polars, AE Aquarii shows a soft X-ray spectrum with a very low luminosity (L_X
~ 10^{31} erg/s). We have analyzed overlapping observations of this system with
the NuSTAR and the Swift X-ray observatories in September of 2012. We find the
0.5-30 keV spectra to be well fitted by either an optically thin thermal plasma
model with three temperatures of 0.75 +0.18 -0.45, 2.29 +0.96 -0.82, and 9.33
+6.07 -2.18 keV, or an optically thin thermal plasma model with two
temperatures of 1.00 +0.34 -0.23 and 4.64 +1.58 -0.84 keV plus a power-law
component with photon index of 2.50 +0.17 -0.23. The pulse profile in the 3-20
keV band is broad and approximately sinusoidal, with a pulsed fraction of 16.6
+/- 2.3%. We do not find any evidence for a previously reported sharp feature
in the pulse profile.


title: Uniform local finiteness of the curve graph via subsurface projections

abstract:
  The curve graphs are not locally finite. In this paper, we show that the
curve graphs satisfy a property which is equivalent to graphs being uniformly
locally finite via Masur--Minsky's subsurface projections. As a direct
application of this study, we show that there exist computable bounds for
Bowditch's slices on tight geodesics, which depend only on the surface. As an
extension of this application, we define a new class of geodesics, weak tight
geodesics, and we also obtain a computable finiteness statement on the
cardinalities of the slices on weak tight geodesics.


title:
Emergence of heavy quasiparticles from a massless Fermi sea: Optical
  conductivity

abstract:
  We study the density of states and the optical conductivity of a Kondo
lattice which is immersed in a massless Dirac Fermi sea, as characterized by a
linear dispersion relation. As a result of the hybridization $V$ with the
$f$-electron levels, the pseudo-gap in the conduction band becomes duplicated
and is shifted both into the upper and the lower quasiparticle band. We find
that due to the linear dispersion of the Dirac fermions, the Kondo insulator
gap is observable in the optical conductivity in contrast to the Kondo lattice
system in a conventional conduction band, and the resulting gap\,[$\Delta_{\rm
gap}(T)$] depends on temperature. The reason is that the Kondo insulator gap is
an {\it indirect gap} in conventional Kondo lattices, while it becomes a {\it
direct gap} in the Dirac Fermi Sea. We find that the optical conductivity
attains two peaks and is vanishing exactly at $2 b(T)V$ where $b$ depends on
temperature.


title: Ergodicity for Time Changed Symmetric Stable Processes

abstract:
  In this paper we study the ergodicity and the related semigroup property for
a class of symmetric Markov jump processes associated with time changed
symmetric $\alpha$-stable processes. For this purpose, explicit and sharp
criteria for Poincar\'{e} type inequalities (including Poincar\'{e}, super
Poincar\'{e} and weak Poincar\'{e} inequalities) of the corresponding non-local
Dirichlet forms are derived. Moreover, our main results, when applied to a
class of one-dimensional stochastic differential equations driven by symmetric
$\alpha$-stable processes, yield sharp criteria for their various ergodic
properties and corresponding functional inequalities.


title: Steepest entropy ascent paths towards the Max-Ent distribution

abstract:
  With reference to two general probabilistic description frameworks,
Information Theory and Classical Statistical Mechanics, we discuss the
geometrical reasoning and mathematical formalism leading to the differential
equation that defines in probability space the smooth path of Steepest Entropy
Ascent (SEA) connecting an arbitrary initial probability distribution to the
unique Maximum Entropy (MaxEnt) distribution with the same mean values of a set
of constraints. The SEA path is relative to a metric chosen to measure
distances in square-root probability distribution space. Along the resulting
SAE path, the metric turns out to be proportional to the concept of Onsager
resistivity generalized to the far non-equilibrium domain. The length of the
SEA path to MaxEnt provides a novel global measure of degree of disequilibrium
(DoD) of the initial probability distribution, whereas a local measure of DoD
is given by the norm of a novel generalized concept of non-equilibrium
affinity.

categories: math-ph cond-mat.stat-mech math.MP physics.data-an


title: Partial regularity for parabolic systems with VMO-coefficients

abstract:
  We establish partial regularity for vector-valued solutions to parabolic
systems where the coefficients are possibly discontinuous with respect to
(x,t). More precisely, we assume a VMO-condition with respect to the (x,t) and
continuity with respect to u and prove H\"older continuity of the solutions
outside of singular sets.


title: Comparative analysis of evolutionary algorithms for image enhancement

abstract:
  Evolutionary algorithms are metaheuristic techniques that derive inspiration
from the natural process of evolution. They can efficiently solve (generate
acceptable quality of solution in reasonable time) complex optimization
(NP-Hard) problems. In this paper, automatic image enhancement is considered as
an optimization problem and three evolutionary algorithms (Genetic Algorithm,
Differential Evolution and Self Organizing Migration Algorithm) are employed to
search for an optimum solution. They are used to find an optimum parameter set
for an image enhancement transfer function. The aim is to maximize a fitness
criterion which is a measure of image contrast and the visibility of details in
the enhanced image. The enhancement results obtained using all three
evolutionary algorithms are compared amongst themselves and also with the
output of histogram equalization method.


title: Electromagnetic way of accelerating the magnetic dipoles

abstract:
  The article considers an opportunity of electrodynamics accelerating the
magnetic dipoles at initial velocity six hundred meters per second, which is
the magnetic dipole gain after pre-gas-dynamic acceleration to finite velocity
eight and half kilometers per second. The acceleration length is more than two
kilometers. When selecting the drag coefficient and the lift coefficient equal
to one hundredth, the dipoles rise to height ten kilometers during a period of
time fourteen seconds, thus reaching the vertical velocity one kilometer per
second and reducing the forward velocity till seven and a half kilometer per
second. The magnetic dipoles reach flight range twelve thousand three hundred
kilometers.


title: Stable Camera Motion Estimation Using Convex Programming

abstract:
  We study the inverse problem of estimating n locations $t_1, ..., t_n$ (up to
global scale, translation and negation) in $R^d$ from noisy measurements of a
subset of the (unsigned) pairwise lines that connect them, that is, from noisy
measurements of $\pm (t_i - t_j)/\|t_i - t_j\|$ for some pairs (i,j) (where the
signs are unknown). This problem is at the core of the structure from motion
(SfM) problem in computer vision, where the $t_i$'s represent camera locations
in $R^3$. The noiseless version of the problem, with exact line measurements,
has been considered previously under the general title of parallel rigidity
theory, mainly in order to characterize the conditions for unique realization
of locations. For noisy pairwise line measurements, current methods tend to
produce spurious solutions that are clustered around a few locations. This
sensitivity of the location estimates is a well-known problem in SfM,
especially for large, irregular collections of images.
  In this paper we introduce a semidefinite programming (SDP) formulation,
specially tailored to overcome the clustering phenomenon. We further identify
the implications of parallel rigidity theory for the location estimation
problem to be well-posed, and prove exact (in the noiseless case) and stable
location recovery results. We also formulate an alternating direction method to
solve the resulting semidefinite program, and provide a distributed version of
our formulation for large numbers of locations. Specifically for the camera
location estimation problem, we formulate a pairwise line estimation method
based on robust camera orientation and subspace estimation. Lastly, we
demonstrate the utility of our algorithm through experiments on real images.


title: Inverse problems and uncertainty quantification

abstract:
  In a Bayesian setting, inverse problems and uncertainty quantification (UQ) -
the propagation of uncertainty through a computational (forward) model - are
strongly connected. In the form of conditional expectation the Bayesian update
becomes computationally attractive. This is especially the case as together
with a functional or spectral approach for the forward UQ there is no need for
time-consuming and slowly convergent Monte Carlo sampling. The developed
sampling-free non-linear Bayesian update is derived from the variational
problem associated with conditional expectation. This formulation in general
calls for further discretisation to make the computation possible, and we
choose a polynomial approximation. After giving details on the actual
computation in the framework of functional or spectral approximations, we
demonstrate the workings of the algorithm on a number of examples of increasing
complexity. At last, we compare the linear and quadratic Bayesian update on the
small but taxing example of the chaotic Lorenz 84 model, where we experiment
with the influence of different observation or measurement operators on the
update.


title:
Gamma-ray emitting narrow-line Seyfert 1 galaxies. New discoveries and
  open questions

abstract:
  The discovery of gamma-ray emission from 5 radio-loud narrow-line Seyfert 1
galaxies revealed the presence of a possible emerging third class of AGNs with
relativistic jets, in addition to blazars and radio galaxies. The existence of
relativistic jets also in this subclass of Seyfert galaxies opened an
unexplored research space for our knowledge of the radio-loud AGNs. Here, we
discuss the radio-to-gamma-rays properties of the gamma-ray emitting
narrow-line Seyfert 1 galaxies, also in comparison with the blazar scenario.