title:
Topological charged black holes in massive gravity's rainbow and their
  thermodynamical analysis through various approaches

abstract:
  Violation of Lorentz invariancy in the high energy quantum gravity motivates
one to consider an energy dependent spacetime with massive deformation of
standard general relativity. In this paper, we take into account an energy
dependent metric in the context of a massive gravity model to obtain exact
solutions. We investigate the geometry of black hole solutions and also
calculate the conserved and thermodynamic quantities, which are fully
reproduced by the analysis performed with the standard techniques. After
examining the validity of the first law of thermodynamics, we conduct a study
regarding the effects of different parameters on thermal stability of the
solutions. In addition, we employ the relation between cosmological constant
and thermodynamical pressure to study the possibility of phase transition.
Interestingly, we will show that for the specific configuration considered in
this paper, van der Waals like behavior is observed for different topology. In
other words, for flat and hyperbolic horizons, similar to spherical horizon, a
second order phase transition and van der Waals like behavior are observed.
Furthermore, we use geometrical method to construct phase space and study phase
transition and bound points for these black holes. Finally, we obtain critical
values in extended phase space through the use of a new method.


title: Near-horizon Kerr Magnetosphere

abstract:
  We exploit the near-horizon conformal symmetry of rapidly spinning black
holes to determine universal properties of their magnetospheres. Analytic
expressions are derived for the limiting form of the magnetosphere in the
near-horizon region. The symmetry is shown to imply that the black hole
Meissner effect holds for free Maxwell fields but is generically violated for
force-free fields. We further show that in the extremal limit, near-horizon
plasma particles are infinitely boosted relative to accretion flow. Active
galactic nuclei powered by rapidly spinning black holes are therefore natural
sites for high-energy particle collisions.


title: Brane Brick Models and 2d (0,2) Triality

abstract:
  We provide a brane realization of 2d (0,2) Gadde-Gukov-Putrov triality in
terms of brane brick models. These are Type IIA brane configurations that are
T-dual to D1-branes over singular toric Calabi-Yau 4-folds. Triality translates
into a local transformation of brane brick models, whose simplest
representative is a cube move. We present explicit examples and construct their
triality networks. We also argue that the classical mesonic moduli space of
brane brick model theories, which corresponds to the probed Calabi-Yau 4-fold,
is invariant under triality. Finally, we discuss triality in terms of phase
boundaries, which play a central role in connecting Calabi-Yau 4-folds to brane
brick models.


title:
Non-classical state generation in macroscopic systems via hybrid
  discrete-continuous quantum measurements

abstract:
  Non-classical state generation is an important component throughout
experimental quantum science for quantum information applications and probing
the fundamentals of physics. Here, we investigate permutations of quantum
non-demolition quadrature measurements and single quanta addition/subtraction
to prepare quantum superposition states in bosonic systems. The performance of
each permutation is quantified and compared using several different
non-classicality criteria including Wigner negativity, non-classical depth, and
optimal fidelity with a coherent state superposition. We also compare the
performance of our protocol using squeezing instead of a quadrature measurement
and find that the purification provided by the quadrature measurement can
significantly increase the non-classicality generated. Our approach is ideally
suited for implementation in light-matter systems such as quantum optomechanics
and atomic spin ensembles, and offers considerable robustness to initial
thermal occupation.


title:
Theory of Multifarious Quantum Phases and Large Anomalous Hall effect in
  Pyrochlore Iridate Thin Films

abstract:
  We theoretically investigate emergent quantum phases in the thin film
geometries of the pyrochore iridates, where a number of exotic quantum ground
states are proposed to occur in bulk materials as a result of the interplay
between electron correlation and strong spin-orbit coupling. The fate of these
bulk phases as well as novel quantum states that may arise only in the thin
film platforms, are studied via a theoretical model that allows layer-dependent
magnetic structures. It is found that the magnetic order develop in
inhomogeneous fashions in the thin film geometries. This leads to a variety of
magnetic metal phases with modulated magnetic ordering patterns across
different layers. Both the bulk and boundary electronic states in these phases
conspire to promote unusual electronic properties. In particular, such phases
are akin to the Weyl semimetal phase in the bulk system and they would exhibit
an unusually large anomalous Hall effect.


title:
The Velocity Distribution Function of Galaxy Clusters as a Cosmological
  Probe

abstract:
  We present a new approach for quantifying the abundance of galaxy clusters
and constraining cosmological parameters using dynamical measurements. In the
standard method, galaxy line-of-sight (LOS) velocities, $v$, or velocity
dispersions are used to infer cluster masses, $M$, in order to quantify the
halo mass function (HMF), $dn(M)/d\log(M)$, which is strongly affected by mass
measurement errors. In our new method, the probability distribution of
velocities for each cluster in the sample are summed to create a new statistic
called the velocity distribution function (VDF), $dn(v)/dv$. The VDF can be
measured more directly and precisely than the HMF and it can also be robustly
predicted with cosmological simulations which capture the dynamics of subhalos
or galaxies. We apply these two methods to mock cluster catalogs and forecast
the bias and constraints on the matter density parameter $\Omega_m$ and the
amplitude of matter fluctuations $\sigma_8$ in flat $\Lambda$CDM cosmologies.
For an example observation of 200 massive clusters, the VDF with (without)
velocity errors constrains the parameter combination $\sigma_8\Omega_m^{0.29\
(0.29)} = 0.587 \pm 0.011\ (0.583 \pm 0.011)$ and shows only minor bias.
However, the HMF with dynamical mass errors is biased to low $\Omega_m$ and
high $\sigma_8$ and the fiducial model lies well outside of the forecast
constraints, prior to accounting for Eddington bias. When the VDF is combined
with constraints from the cosmic microwave background (CMB), the degeneracy
between cosmological parameters can be significantly reduced. Upcoming
spectroscopic surveys that probe larger volumes and fainter magnitudes will
provide a larger number of clusters for applying the VDF as a cosmological
probe.


title:
The SLUGGS survey: Exploring the globular cluster systems of the Leo II
  group and their global relationships

abstract:
  We present an investigation of the globular cluster (GC) systems of NGC 3607
and NGC 3608 as part of the ongoing SLUGGS survey. We use wide-field imaging
data from the Subaru telescope in the g, r, and i filters to analyse the radial
density, colour and azimuthal distributions of both GC systems. With the
complementary kinematic data obtained from the Keck II telescope, we measure
the radial velocities of a total of 81 GCs.
  Our results show that the GC systems of NGC 3607 and NGC 3608 have a
detectable spatial extent of ~ 15, and 13 galaxy effective radii, respectively.
Both GC systems show a clear bimodal colour distribution. We detect a
significant radial colour gradient for the GC subpopulations in both galaxies.
NGC 3607 exhibits an overabundance of red GCs on the galaxy minor axis and NGC
3608 shows a misalignment in the GC subpopulation position angles with respect
to the galaxy stellar component.
  With the aid of literature data, we discuss several relationships between the
properties of GC systems and their host galaxies. A one-to-one relation between
the ellipticities of red GCs and the galaxy stellar light emphasises the
evolutionary similarities between them. In our sample of four slowly rotating
galaxies with kinematically decoupled cores, we observe a higher ellipticity
for the blue GC subpopulation than their red counterparts. Also, we notice the
flattening of negative colour gradients for the blue GC subpopulations with
increasing galaxy stellar mass. Finally, we discuss the formation scenarios
associated with the blue GC subpopulation.


title:
Large scale distribution of total mass versus luminous matter from
  Baryon Acoustic Oscillations: First search in the SDSS-III BOSS Data Release
  10

abstract:
  Baryon Acoustic Oscillations (BAOs) in the early Universe are predicted to
leave an as yet undetected signature on the relative clustering of total mass
versus luminous matter. A detection of this effect would provide an important
confirmation of the standard cosmological paradigm and constrain alternatives
to dark matter as well as non-standard fluctuations such as Compensated
Isocurvature Perturbations (CIPs). We conduct the first observational search
for this effect, by comparing the number-weighted and luminosity-weighted
correlation functions, using the SDSS-III BOSS Data Release 10 CMASS sample.
When including CIPs in our model, we formally obtain evidence at $3.2\sigma$ of
the relative clustering signature and a limit that matches the existing upper
limits on the amplitude of CIPs. However, various tests suggest that these
results are not yet robust, perhaps due to systematic biases in the data. The
method developed in this Letter, used with more accurate future data such as
that from DESI, is likely to confirm or disprove our preliminary evidence.


title:
Size evolution of star-forming galaxies with $2<z<4.5$ in the VIMOS
  Ultra-Deep Survey

abstract:
  We measure galaxy sizes on a sample of $\sim1200$ galaxies with confirmed
spectroscopic redshifts $2 \leq z_{spec} \leq 4.5$ in the VIMOS Ultra Deep
Survey (VUDS), representative of star-forming galaxies with $i_\mathrm{AB} \leq
25$. We first derive galaxy sizes applying a classical parametric profile
fitting method using GALFIT. We then measure the total pixel area covered by a
galaxy above a given surface brightness threshold, which overcomes the
difficulty of measuring sizes of galaxies with irregular shapes. We then
compare the results obtained for the equivalent circularized radius enclosing
100\% of the measured galaxy light $r_T^{100}$ to those obtained with the
effective radius $r_{e,\mathrm{circ}}$ measured with GALFIT. We find that the
sizes of galaxies computed with our non-parametric approach span a large range
but remain roughly constant on average with a median value $r_T^{100}\sim2.2$
kpc for galaxies with $2<z<4.5$. This is in stark contrast with the strong
downward evolution of $r_e$ with increasing redshift, down to sizes of $<1$ kpc
at $z\sim4.5$. We analyze the difference and find that parametric fitting of
complex, asymmetric, multi-component galaxies is severely underestimating their
sizes. By comparing $r_T^{100}$ with physical parameters obtained through SED
fitting we find that the star-forming galaxies that are the largest at any
redshift are, on average, more massive and more star-forming. We discover that
galaxies present more concentrated light profiles as we move towards higher
redshifts. We interpret these results as the signature of several, possibly
different, evolutionary paths of galaxies in their early stages of assembly,
including major and minor merging or star-formation in multiple bright regions.
(abridged)


title:
The extended epoch of galaxy formation: age dating of ~3600 galaxies
  with 2<z<6.5 in the VIMOS Ultra-Deep Survey

abstract:
  We aim at improving constraints on the epoch of galaxy formation by measuring
the ages of 3597 galaxies with spectroscopic redshifts 2<z<6.5 in the VIMOS
Ultra Deep Survey (VUDS). We derive ages and other physical parameters from the
simultaneous fitting with the GOSSIP+ software of observed UV rest-frame
spectra and photometric data from the u-band up to 4.5 microns using composite
stellar population models. We conclude from extensive simulations that at z>2
the joint analysis of spectroscopy and photometry combined with restricted age
possibilities when taking into account the age of the Universe substantially
reduces systematic uncertainties and degeneracies in the age derivation. We
find galaxy ages ranging from very young with a few tens of million years to
substantially evolved with ages up to ~1.5-2 Gyr. The formation redshifts z_f
derived from the measured ages indicate that galaxies may have started forming
stars as early as z_f~15. We produce the formation redshift function (FzF), the
number of galaxies per unit volume formed at a redshift z_f, and compare the
FzF in increasing redshift bins finding a remarkably constant 'universal' FzF.
The FzF is parametrized with (1+z)^\zeta, with \zeta~0.58+/-0.06, indicating a
smooth 2 dex increase from z~15 to z~2. Remarkably this observed increase is of
the same order as the observed rise in the star formation rate density (SFRD).
The ratio of the SFRD with the FzF gives an average SFR per galaxy of
~7-17Msun/yr at z~4-6, in agreement with the measured SFR for galaxies at these
redshifts. From the smooth rise in the FzF we infer that the period of galaxy
formation extends from the highest possible redshifts that we can probe at z~15
down to redshifts z~2. This indicates that galaxy formation is a continuous
process over cosmic time, with a higher number of galaxies forming at the peak
in SFRD at z~2 than at earlier epochs. (Abridged)


title:
The VIMOS Ultra Deep Survey First Data Release: spectra and
  spectroscopic redshifts of 698 objects up to z~6 in CANDELS

abstract:
  This paper describes the first data release (DR1) of the VIMOS Ultra Deep
Survey (VUDS). The DR1 includes all low-resolution spectroscopic data obtained
in 276.9 arcmin2 of the CANDELS-COSMOS and CANDELS-ECFDS survey areas,
including accurate spectroscopic redshifts z_spec and individual spectra
obtained with VIMOS on the ESO-VLT. A total of 698 objects have a measured
redshift, with 677 galaxies, two type-I AGN and a small number of 19
contaminating stars. The targets of the spectroscopic survey are selected
primarily on the basis of their photometric redshifts to ensure a broad
population coverage. About 500 galaxies have z_spec>2, 48 with z_spec>4, and
the highest reliable redshifts reach beyond z_spec=6. This dataset
approximately doubles the number of galaxies with spectroscopic redshifts at
z>3 in these fields. We discuss the general properties of the sample in terms
of the spectroscopic redshift distribution, the distribution of Lyman-alpha
equivalent widths, and physical properties including stellar masses M_star and
star formation rates (SFR) derived from spectral energy distribution fitting
with the knowledge of z_spec. We highlight the properties of the most massive
star-forming galaxies, noting the large range in spectral properties, with
Lyman-alpha in emission or in absorption, and in imaging properties with
compact, multi-component or pair morphologies. We present the catalogue
database and data products. All data are publicly available and can be
retrieved from a dedicated query-based database available at
http://cesam.lam.fr/vuds.


title:
The Launching of Cold Clouds by Galaxy Outflows II: The Role of Thermal
  Conduction

abstract:
  We explore the impact of electron thermal conduction on the evolution of
radiatively-cooled cold clouds embedded in flows of hot and fast material, as
occur in outflowing galaxies. Performing a parameter study of three-dimensional
adaptive mesh refinement hydrodynamical simulations, we show that electron
thermal conduction causes cold clouds to evaporate, but it can also extend
their lifetimes by compressing them into dense filaments. We distinguish
between low column-density clouds, which are disrupted on very short times, and
high-column density clouds with much-longer disruption times that are set by a
balance between impinging thermal energy and evaporation. We provide fits to
the cloud lifetimes and velocities that can be used in galaxy-scale simulations
of outflows, in which the evolution of individual clouds cannot be modeled with
the required resolution. Moreover, we show that the clouds are only accelerated
to a small fraction of the ambient velocity because compression by evaporation
causes the clouds to present a small cross-section to the ambient flow. This
means that either magnetic fields must suppress thermal conduction, or that the
cold clouds observed in galaxy outflows are not formed of cold material carried
out from the galaxy.


title:
The very wide-field $gzK$ galaxy survey -- I. Details of the clustering
  properties of star-forming galaxies at $z \sim 2$

abstract:
  We present the results of clustering analysis on the $z \sim 2$ star-forming
galaxies. By combining our data with data from publicly available archives, we
collect $g$-, $\zb / z$-, and $K$-band imaging data over 5.2 deg$^{2}$, which
represents the largest area BzK/gzK survey. We apply colour corrections to
translate our filter-set to those used in the original BzK selection for the
gzK selection. Because of the wide survey area, we obtain a sample of 41,112
star-forming gzK galaxies at $z \sim 2$ (sgzKs) down to $\KAB < 23.0$, and
determine high-quality two-point angular correlation functions (ACFs). Our ACFs
show an apparent excess from power-law behaviour at small angular scale
$(\theta \la 0.01^{\circ})$, which corresponds the virial radius of a dark halo
at $z \sim 2$ with a mass of $\sim 10^{13} \Msun$. We find that the correlation
lengths are consistent with the previous estimates over all magnitude range;
however, our results are evaluated with a smaller margin of error than that in
previous studies. The large amount of data enables us to determine ACFs
differentially depending on the luminosity of the subset of the data. The mean
halo mass of faint sgzKs $(22.0 < K \leq 23.0)$ was found to be $\Mh =
(1.32^{+0.09}_{-0.12}) \times 10^{12} h^{-1} \Msun$, whereas bright sgzKs
($18.0 \leq K \leq 21.0)$ were found to reside in dark haloes with a mass of
$\Mh = (3.26^{+1.23}_{-1.02}) \times 10^{13} h^{-1} \Msun$.


title:
The very wide-field $gzK$ galaxy survey -- II. The relationship between
  star-forming galaxies at $z \sim 2$ and their host haloes based upon HOD
  modelling

abstract:
  We present the results of an halo occupation distribution (HOD) analysis of
star-forming galaxies at $z \sim 2$. We obtained high-quality angular
correlation functions based on a large sgzK sample, which enabled us to carry
out the HOD analysis. The mean halo mass and the HOD mass parameters are found
to increase monotonically with increasing $K$-band magnitude, suggesting that
more luminous galaxies reside in more massive dark haloes. The luminosity
dependence of the HOD mass parameters was found to be the same as in the local
Universe; however, the masses were larger than in the local Universe over all
ranges of magnitude. This implies that galaxies at $z \sim 2$ tend to form in
more massive dark haloes than in the local Universe, a process known as
downsizing. By analysing the dark halo mass evolution using the extended
Press--Schechter formalism and the number evolution of satellite galaxies in a
dark halo, we find that faint Lyman break galaxies at $z \sim 4$ could evolve
into the faintest sgzKs $(22.0 < K \leq 23.0)$ at $z \sim 2$ and into the
Milky-Way-like galaxies or elliptical galaxies in the local Universe, whereas
the most luminous sgzKs $(18.0 \leq K \leq 21.0)$ could evolve into the most
massive systems in the local Universe. The stellar-to-halo mass ratio (SHMR) of
the sgzKs was found to be consistent with the prediction of the model, except
that the SHMR of the faintest sgzKs was smaller than the prediction at $z \sim
2$. This discrepancy may be attributed that our samples are confined to
star-forming galaxies.


title: The cosmic assembly of stellar haloes in massive Early-Type Galaxies

abstract:
  Using the exquisite depth of the Hubble Ultra Deep Field (HUDF12 programme)
dataset, we explore the ongoing assembly of the outermost regions of the most
massive galaxies ($\rm M_{\rm stellar}\geq$ 5$\times$10$^{10}$ M$_{\odot}$) at
$z \leq$ 1. The outskirts of massive objects, particularly Early-Types Galaxies
(ETGs), are expected to suffer a dramatic transformation across cosmic time due
to continuous accretion of small galaxies. HUDF imaging allows us to study this
process at intermediate redshifts in 6 massive galaxies, exploring the
individual surface brightness profiles out to $\sim$25 effective radii. We find
that 5-20\% of the total stellar mass for the galaxies in our sample is
contained within 10 $< R <$ 50 kpc. These values are in close agreement with
numerical simulations, and higher than those reported for local late-type
galaxies ($\lesssim$5\%). The fraction of stellar mass stored in the outer
envelopes/haloes of Massive Early-Type Galaxies increases with decreasing
redshift, being 28.7\% at $< z > =$ 0.1, 15.1\% at $< z > =$ 0.65 and 3.5\% at
$< z > =$ 2. The fraction of mass in diffuse features linked with ongoing minor
merger events is $>$ 1-2\%, very similar to predictions based on observed close
pair counts. Therefore, the results for our small albeit meaningful sample
suggest that the size and mass growth of the most massive galaxies have been
solely driven by minor and major merging from $z =$ 1 to today.


title:
Prescriptions for measuring and transporting local angular momenta in
  general relativity

abstract:
  For observers in curved spacetimes, elements of the dual space of the set of
linearized Poincar\'e transformations from an observer's tangent space to
itself can be naturally interpreted as local linear and angular momenta. We
present an operational procedure by which observers can measure such quantities
using only information about the spacetime curvature at their location. When
applied by observers near spacelike or null infinity in stationary, vacuum,
asymptotically flat spacetimes, there is a sense in which the procedure yields
the well-defined linear and angular momenta of the spacetime.
  We also describe a general method by which observers can transport local
linear and angular momenta from one point to another, which improves previous
prescriptions. This transport is not path independent in general, but becomes
path independent for the measured momenta in the same limiting regime. The
transport prescription is defined in terms of differential equations, but it
can also be interpreted as parallel transport in a particular direct-sum vector
bundle. Using the curvature of the connection on this bundle, we compute and
discuss the holonomy of the transport law. We anticipate that these measurement
and transport definitions may ultimately prove useful for clarifying the
physical interpretation of the Bondi-Metzner-Sachs charges of asymptotically
flat spacetimes.


title: Stochastic modeling of cell growth with symmetric or asymmetric division

abstract:
  We consider a class of biologically-motivated stochastic processes in which a
unicellular organism divides its resources (volume or damaged proteins, in
particular) symmetrically or asymmetrically between its progeny. Assuming the
final amount of the resource is controlled by a growth policy and subject to
additive and multiplicative noise, we derive the "master equation" describing
how the resource distribution evolves over subsequent generations and use it to
study the properties of stable resource distributions. We find conditions under
which a unique stable resource distribution exists and calculate its moments
for the class of affine linear growth policies. Moreover, we apply an
asymptotic analysis to elucidate the conditions under which the stable
distribution (when it exists) has a power-law tail. Finally, we use the results
of this asymptotic analysis along with the moment equations to draw a stability
phase diagram for the system that reveals the counterintuitive result that
asymmetry serves to increase stability while at the same time widening the
stable distribution. We also briefly discuss how cells can divide damaged
proteins asymmetrically between their progeny as a form of damage control. In
the appendix, motivated by the asymmetric division of cell volume in
Saccharomyces cerevisiae, we extend our results to the case wherein mother and
daughter cells follow different growth policies.


title:
Quantum nonergodicity and fermion localization in a system with a
  single-particle mobility edge

abstract:
  We study the many-body localization aspects of single-particle mobility edges
in fermionic systems. We investigate incommensurate lattices and random
disorder Anderson models. Many-body localization and quantum nonergodic
properties are studied by comparing entanglement and thermal entropy, and by
calculating the scaling of subsystem particle number fluctuations,
respectively. We establish a nonergodic extended phase as a generic
intermediate phase (between purely ergodic extended and nonergodic localized
phases) for the many-body localization transition of non-interacting fermions
where the entanglement entropy manifests a volume law (`extended'), but there
are large fluctuations in the subsystem particle numbers (`nonergodic'). We
argue such an intermediate phase scenario may continue holding even for the
many-body localization in the presence of interactions as well. We find for
many-body states in non-interacting 1d Aubry-Andre and 3d Anderson models that
the entanglement entropy density and the normalized particle-number fluctuation
have discontinuous jumps at the localization transition where the entanglement
entropy is sub-thermal but obeys the "volume law". In the vicinity of the
localization transition we find that both the entanglement entropy and the
particle number fluctuations obey a single parameter scaling. We argue using
numerical and theoretical results that such a critical scaling behavior should
persist for the interacting many-body localization problem with important
consequences. Our work provides persuasive evidence in favor of there being two
transitions in many-body systems with single-particle mobility edges, the first
one indicating a transition from the purely localized nonergodic many-body
localized phase to a nonergodic extended many-body metallic phase, and the
second one being a transition eventually to the usual ergodic many-body
extended phase.


title: Classical noise and the structure of minimal uncertainty states

abstract:
  Which quantum states minimise the unavoidable uncertainty arising from the
non-commutativity of two observables? The immediate answer to such a question
is: it depends. Due to the plethora of uncertainty measures there are many
answers. Here, instead of restricting our study to a particular measure, we
present plausible axioms for the set $\mathcal{F}$ of bona-fide
information-theoretic uncertainty functions. Then, we discuss the existence of
states minimising uncertainty with respect to all members of $\mathcal{F}$,
i.e., universal minimum uncertainty states (MUS). We prove that such states do
not exist within the full state space and study the effect of classical noise
on the structure of minimum uncertainty states. We present an explicit example
of a qubit universal MUS that arises when purity is constrained by introducing
a threshold amount of noise. For higher dimensional systems we derive several
no-go results limiting the existence of noisy universal MUS. However, we
conjecture that universality may emerge in an approximate sense. We conclude by
discussing connections with thermodynamics, and highlight the privileged role
that non-equilibrium free energy $F_2$ plays close to equilibrium.


title:
The K2-ESPRINT Project II: Spectroscopic follow-up of three exoplanet
  systems from Campaign 1 of K2

abstract:
  We report on Doppler observations of three transiting planet candidates that
were detected during Campaign 1 of the K2 mission. The Doppler observations
were conducted with FIES, HARPS-N and HARPS. We measure the mass of K2-27b
(EPIC 201546283b), and provide constraints and upper limits for EPIC 201295312b
and EPIC 201577035b. K2-27b is a warm Neptune orbiting its host star in 6.77
days and has a radius of $4.45^{+0.33}_{-0.33}~\mathrm{R_\oplus}$ and a mass of
$29.1^{+7.5}_{-7.4}~\mathrm{M_\oplus}$, which leads to a mean density of
$1.80^{+0.70}_{-0.55}~\mathrm{g~cm^{-3}}$. EPIC 201295312b is smaller than
Neptune with an orbital period of 5.66 days, radius
$2.75^{+0.24}_{-0.22}~\mathrm{R_\oplus}$ and we constrain the mass to be below
$12~\mathrm{M_\oplus}$ at 95% confidence. We also find a long-term trend
indicative of another body in the system. EPIC 201577035b, previously confirmed
as the planet K2-10b, is smaller than Neptune orbiting its host star in 19.3
days, with radius $3.84^{+0.35}_{-0.34}~\mathrm{R_\oplus}$. We determine its
mass to be $27^{+17}_{-16}~\mathrm{M_\oplus}$, with a 95% confidence uppler
limit at $57~\mathrm{M_\oplus}$, and mean density $2.6^{+2.1}_{-1.6}~{\rm
g~cm}^{-3}$. These measurements join the relatively small collection of planets
smaller than Neptune with measurements or constraints of the mean density. Our
code for performing K2 photometry and detecting planetary transits is now
publicly available.


title: Involutory quandles of (2,2,r)-Montesinos links

abstract:
  In this paper we show that Montesinos links of the form L(1/2, 1/2, p/q;e),
which we call (2,2,r)-Montesinos links, have finite involutory quandles. This
generalizes an observation of Winker regarding the (2, 2, q)-pretzel links. We
also describe some properties of these quandles.


title: Covariant Hyperbolization of Force-free Electrodynamics

abstract:
  Force-Free Flectrodynamics (FFE) is a non-linear system of equations modeling
the evolution of the electromagnetic field, in the presence of a magnetically
dominated relativistic plasma. This configuration arises on several
astrophysical scenarios, which represent exciting laboratories to understand
physics in extreme regimes. We show that this system, when restricted to the
correct constraint submanifold, is symmetric hyperbolic. In numerical
applications is not feasible to keep the system in that submanifold, and so, it
is necessary to analyze its structure first in the tangent space of that
submanifold and then in a whole neighborhood of it. As already shown by
Pfeiffer, a direct (or naive) formulation of this system (in the whole tangent
space) results in a weakly hyperbolic system of evolution equations for which
well-possednes for the initial value formulation does not follows.
  Using the generalized symmetric hyperbolic formalism due to Geroch, we
introduce here a covariant hyperbolization for the FFE system. In fact, in
analogy to the usual Maxwell case, a complete family of hyperbolizers is found,
both for the restricted system on the constraint submanifold as well as for a
suitably extended system defined in a whole neighborhood of it. A particular
symmetrizer among the family is then used to write down the pertaining
evolution equations, in a generic ($3+1$)-decomposition on a background
spacetime. Interestingly, it turns out that for a particular choice of the
lapse and shift functions of the foliation, our symmetrized system reduces to
the one found by Pfeiffer. Finally we analyze the characteristic structure of
the resulting evolution system.


title: APOGEE strings: a fossil record of the gas kinematic structure

abstract:
  We compare APOGEE radial velocities (RVs) of young stars in the Orion A cloud
with CO line gas emission and find a correlation between the two at
large-scales, in agreement with previous studies. However, at smaller scales we
find evidence for the presence of substructure in the stellar velocity field.
Using a Friends-of-Friends approach we identify 37 stellar groups with almost
identical RVs. These groups are not randomly distributed but form elongated
chains or strings of stars with five or more members with low velocity
dispersion, across lengths of 1-1.5~pc. The similarity between the kinematic
properties of the APOGEE strings and the internal velocity field of the chains
of dense cores and fibers recently identified in the dense ISM is striking and
suggests that for most of the Orion A cloud, young stars keep memory of the
parental gas substructure where they originated.


title: Scaling behavior of the Compton profile of alkali metals

abstract:
  The contribution of the valence electrons to the Compton profiles of the
alkali metals is calculated using density functional theory. We show that the
Compton profiles can be modeled by a $q-$Gaussian distribution, which is
characterized by an anisotropic, element dependent parameter $q$. Thereby we
derive an unexpected scaling behavior of the Compton profiles of all alkali
metals.


title:
The clustering amplitude of X-ray selected AGN at z=0.8: Evidence for a
  negative dependence on accretion luminosity

abstract:
  The northern tile of the wide-area and shallow XMM-XXL X-ray survey field is
used to estimate the average dark matter halo mass of relatively luminous X-ray
selected AGN [$\rm
  log\, L_X (\rm 2-10\,keV)= 43.6^{+0.4}_{-0.4}\,erg/s$] in the redshift
interval $z=0.5-1.2$. Spectroscopic follow-up observations of X-ray sources in
the XMM-XXL field by the Sloan telescope are combined with the VIPERS
spectroscopic galaxy survey to determine the cross-correlation signal between
X-ray selected AGN (total of 318) and galaxies (about 20,\,000). We model the
large scales (2-25\,Mpc) of the correlation function to infer a mean dark
matter halo mass of $\log M / (M_{\odot} \, h^{-1}) = 12.50 ^{+0.22} _{-0.30}$
for the X-ray selected AGN sample. This measurement is about 0.5\,dex lower
compared to estimates in the literature of the mean dark matter halo masses of
moderate luminosity X-ray AGN [$L_X (\rm 2-10\,keV)\approx 10^{42} -
  10^{43}\,erg/s$] at similar redshifts. Our analysis also links the mean
clustering properties of moderate luminosity AGN with those of powerful
UV/optically selected QSOs, which are typically found in halos with masses few
times $10^{12}\,M_{\odot}$. There is therefore evidence for a negative
luminosity dependence of the AGN clustering. This is consistent with
suggestions that AGN have a broad dark matter halo mass distribution with a
high mass tail that becomes sub-dominant at high accretion luminosities. We
further show that our results are in qualitative agreement with semi-analytic
models of galaxy and AGN evolution, which attribute the wide range of dark
matter halo masses among the AGN population to different triggering mechanisms
and/or black hole fueling modes.


title:
Error Sensitivity to Environmental Noise in Quantum Circuits for
  Chemical State Preparation

abstract:
  Calculating molecular energies is likely to be one of the first useful
applications to achieve quantum supremacy, performing faster on a quantum than
a classical computer. However, if future quantum devices are to produce
accurate calculations, errors due to environmental noise and algorithmic
approximations need to be characterized and reduced. In this study, we use the
high performance qHiPSTER software to investigate the effects of environmental
noise on the preparation of quantum chemistry states. We simulated eighteen
16-qubit quantum circuits under environmental noise, each corresponding to a
unitary coupled cluster state preparation of a different molecule or molecular
configuration. Additionally, we analyze the nature of simple gate errors in
noise-free circuits of up to 40 qubits. We find that the Jordan-Wigner (JW)
encoding produces consistently smaller errors under a noisy environment as
compared to the Bravyi-Kitaev (BK) encoding. For the JW encoding,
pure-dephasing noise is shown to produce substantially smaller errors than pure
relaxation noise of the same magnitude. We report error trends in both
molecular energy and electron particle number within a unitary coupled cluster
state preparation scheme, against changes in nuclear charge, bond length,
number of electrons, noise types, and noise magnitude. These trends may prove
to be useful in making algorithmic and hardware-related choices for quantum
simulation of molecular energies.


title: Superintegrability of $d$-dimensional Conformal Blocks

abstract:
  We observe that conformal blocks of scalar 4-point functions in a
$d$-dimensional conformal field theory can mapped to eigenfunctions of a
2-particle hyperbolic Calogero-Sutherland Hamiltonian. The latter describes two
coupled P\"oschl-Teller particles. Their interaction, whose strength depends
smoothly on the dimension $d$, is known to be superintegrable. Our observation
enables us to exploit the rich mathematical literature on Calogero-Sutherland
models in deriving various results for conformal field theory. These include an
explicit construction of conformal blocks in terms of Heckman-Opdam
hypergeometric functions and a remarkable duality that relates the blocks of
theories in different dimensions.


title:
Comment on "Significant-Loophole-Free Test of Bell's Theorem with
  Entangled Photons"

abstract:
  In a recent article Giustina et al. [Phys. Rev. Lett. 115, 250401 (2015)]
report on an advanced Bell experiment, simultaneously closing loopholes for
local hidden-variable theories. The authors claim that 'local realism' has been
refuted, unless 'truly exotic hypotheses' are made. Here I argue that a
particularly wide and natural class of local hidden-variable theories survives,
for instance when the hidden variables describe a background field. Such
background-based theories exploit the freedom-of-choice loophole, which cannot
be closed for this type of hidden variables. The dynamics of such models can be
illustrated by existing systems, e.g. from fluid mechanics.


title:
On directional derivatives of Skorokhod maps in convex polyhedral
  domains

abstract:
  The study of both sensitivity analysis and differentiability of the
stochastic flow of a reflected process in a convex polyhedral domain is
challenging because the dynamics are discontinuous at the boundary of the
domain and the boundary of the domain is not smooth. These difficulties can be
addressed by studying directional derivatives of an associated extended
Skorokhod map, which is a deterministic mapping that takes an unconstrained
path to a suitably reflected version. In this work we develop an axiomatic
framework for the analysis of directional derivatives of a large class of
Lipschitz continuous extended Skorokhod maps in convex polyhedral domains with
oblique directions of reflection. We establish existence of directional
derivatives at a path whose reflected version satisfies a certain boundary
jitter property, and also show that the right-continuous regularization of such
a directional derivative can be characterized as the unique solution to a
Skorokhod-type problem, where both the domain and directions of reflection vary
(discontinuously) with time. A key ingredient in the proof is establishing
certain contraction properties for a family of (oblique) derivative projection
operators. As an application, we establish pathwise differentiability of
reflected Brownian motion in the nonnegative quadrant with respect to the
initial condition, drift vector, dispersion matrix and directions of
reflection. The results of this paper are also used in subsequent work to
establish pathwise differentiability of a much larger class of reflected
diffusions in convex polyhedral domains.


title: Twisted geometries, twistors and conformal transformations

abstract:
  The twisted geometries of spin network states are described by simple
twistors, isomorphic to null twistors with a time-like direction singled out.
The isomorphism depends on the Immirzi parameter, and reduces to the identity
when the parameter goes to infinity. Using this twistorial representation we
study the action of the conformal group SU(2,2) on the classical phase space of
loop quantum gravity, described by twisted geometry. The generators of
translations and conformal boosts do not preserve the geometric structure,
whereas the dilatation generator does. It corresponds to a 1-parameter family
of embeddings of T*SL(2,C) in twistor space, and its action preserves the
intrinsic geometry while changing the extrinsic one - that is the boosts among
polyhedra. We discuss the implication of this action from a dynamical point of
view, and compare it with a discretisation of the dilatation generator of the
continuum phase space, given by the Lie derivative of the group character. At
leading order in the continuum limit, the latter reproduces the same
transformation of the extrinsic geometry, while also rescaling the areas and
volumes and preserving the angles associated with the intrinsic geometry. Away
from the continuum limit its action has an interesting non-linear structure,
but is in general incompatible with the closure constraint needed for the
geometric interpretation. As a side result, we compute the precise relation
between the extrinsic geometry used in twisted geometries and the one defined
in the gauge-invariant parametrization by Dittrich and Ryan, and show that the
secondary simplicity constraints they posited coincide with those dynamically
derived in the toy model of [1409.0836].


title:
Large-scale 3D mapping of the intergalactic medium using the Lyman Alpha
  Forest

abstract:
  Maps of the large-scale structure of the Universe at redshifts 2-4 can be
made with the Lyman-alpha forest which are complementary to low redshift galaxy
surveys. We apply the Wiener interpolation method of Caucci et al. to construct
three-dimensional maps from sets of Lyman-alpha forest spectra taken from
cosmological hydrodynamic simulations. We mimic some current and future quasar
redshift surveys (BOSS, eBOSS and MS-DESI) by choosing similar sightline
densities. We use these appropriate subsets of the Lyman-alpha absorption
sightlines to reconstruct the full three dimensional Lyman-alpha flux field and
perform comparisons between the true and the reconstructed fields. We study
global statistical properties of the intergalactic medium (IGM) maps with
auto-correlation and cross-correlation analysis, slice plots, local peaks and
point by point scatter. We find that both the density field and the statistical
proper- ties of the IGM are recovered well enough that the resulting IGM maps
can be meaningfully considered to represent large-scale maps of the Universe in
agreement with Caucci et al., on larger scales and for sparser sightlines than
had been tested previously. Quantitatively, for sightline parameters comparable
to current and near future surveys the correlation coefficient between true and
reconstructed fields is r > 0.9 on scales > 30 h^-1 Mpc. The properties of the
maps are relatively insensitive to the precise form of the covariance matrix
used. The final BOSS quasar Lyman-alpha forest sample will allow maps to be
made with a resolution of ~ 30 h^-1 Mpc over a volume of ~ 15 h^-3 Gpc^3
between redshifts 1.9 and 2.3.


title:
Efficient On-the-Fly Interpolation Technique for Bethe-Salpeter
  Calculations of Optical Spectra

abstract:
  The Bethe-Salpeter formalism represents the most accurate method available
nowadays for computing neutral excitation energies and optical spectra of
crystalline systems from first principles. Bethe-Salpeter calculations yield
very good agreement with experiment but are notoriously difficult to converge
with respect to the sampling of the electronic wavevectors. Well-converged
spectra therefore require significant computational and memory resources, even
by today's standards. These bottlenecks hinder the investigation of systems of
great technological interest. They are also barriers to the study of derived
quantities like piezoreflectance, thermoreflectance or resonant Raman
intensities.
  We present a new methodology that decreases the workload needed to reach a
given accuracy. It is based on a double-grid on-the-fly interpolation within
the Brillouin zone, combined with the Lanczos algorithm. It achieves
significant speed-up and reduction of memory requirements. The technique is
benchmarked in terms of accuracy on silicon, gallium arsenide and lithium
fluoride. The scaling of the performance of the method as a function of the
Brillouin Zone point density is much better than a conventional implementation.
We also compare our method with other similar techniques proposed in the
literature.


title:
Existence of periodic solution for a class of neutral differential
  equations with impulses

abstract:
  By applying a Mawhin's continuation theorem of coincidence degree theory, we
establish sufficient conditions for the existence of a periodic solution for a
class of impulsive neutral differential equations. The procedure adopted in
this work makes use of a non-impulsive associated equation in order to overcome
the difficulties resulting from the moments of impulse effects. Under
particular assumptions this solution is continuously differentiable on each
interval with no impulse effect.


title:
Assessment of the Effects of Azimuthal Mode Number Perturbations upon
  the Implosion Processes of Fluids in Cylinders

abstract:
  Fluid instabilities arise in a variety of contexts and are often unwanted
results of engineering imperfections. In one particular model for a magnetized
target fusion reactor, a pressure wave is propagated in a cylindrical annulus
comprised of a dense fluid before impinging upon a plasma and imploding it.
Part of the success of the apparatus is a function of how axially-symmetric the
final pressure pulse is upon impacting the plasma. We study a simple model for
the implosion of the system to study how imperfections in the pressure imparted
on the outer circumference grow due to geometric focusing. Our methodology
entails linearizing the compressible Euler equations for mass and momentum
conservation about a cylindrically symmetric problem and analyzing the
perturbed profiles at different mode numbers. The linearized system gives rise
to singular shocks and through analyzing the perturbation profiles at various
times, we infer that high mode numbers are dampened through the propagation. We
also study the Linear Klein-Gordon equation in the context of stability of
linear cylindrical wave formation whereby highly oscillatory, bounded behaviour
is observed in a far field solution.


title: Cofinite Graphs and their Profinite Completions

abstract:
  We generalize the idea of cofinite groups, due to B. Hartley. First we define
cofinite spaces in general. Then, as a special situation, we study cofinite
graphs and their uniform completions.
  The idea of constructing a cofinite graph starts with defining a uniform
topological graph Gamma, in an appropriate fashion. We endow abstract graphs
with uniformities corresponding to separating filter bases of equivalence
relations with finitely many equivalence classes over Gamma. It is established
that for any cofinite graph there exists a unique cofinite completion.


title:
Scheduling of unit-length jobs with bipartite incompatibility graphs on
  four uniform machines

abstract:
  In the paper we consider the problem of scheduling $n$ identical jobs on 4
uniform machines with speeds $s_1 \geq s_2 \geq s_3 \geq s_4,$ respectively.
Our aim is to find a schedule with a minimum possible length. We assume that
jobs are subject to some kind of mutual exclusion constraints modeled by a
bipartite incompatibility graph of degree $\Delta$, where two incompatible jobs
cannot be processed on the same machine. We show that the problem is NP-hard
even if $s_1=s_2=s_3$. If, however, $\Delta \leq 4$ and $s_1 \geq 12 s_2$,
$s_2=s_3=s_4$, then the problem can be solved to optimality in time
$O(n^{1.5})$. The same algorithm returns a solution of value at most 2 times
optimal provided that $s_1 \geq 2s_2$. Finally, we study the case $s_1 \geq s_2
\geq s_3=s_4$ and give an $O(n^{1.5})$-time $32/15$-approximation algorithm in
all such situations.


title:
2nd Workshop on Cognitive Architectures for Social Human-Robot
  Interaction 2016 (CogArch4sHRI 2016)

abstract:
  This volume is the proceedings of the 2nd workshop on Cognitive Architectures
for Social Human-Robot Interaction, held at the ACM/IEEE HRI 2016 conference,
which took place on Monday 7th March 2016, in Christchurch, New Zealand.
  Organised by Paul Baxter (Plymouth University, U.K.), J. Gregory Trafton
(Naval Research Laboratory, USA), and Severin Lemaignan (Plymouth University,
U.K.).


title: Arithmetic Progressions in the Primitive Length Spectrum

abstract:
  In this article, we prove that every arithmetic locally symmetric orbifold of
classical type without Euclidean or compact factors has arbitrarily long
arithmetic progressions in its primitive length spectrum. Moreover, we show the
stronger property that every primitive length occurs in arbitrarily long
arithmetic progressions in its primitive length spectrum. This confirms one
direction of a conjecture of Lafont--McReynolds, which states that the property
of having every primitive length occur in arbitrarily long arithmetic
progressions characterizes the arithmeticity of such spaces.


title: Polar Coding for Processes with Memory

abstract:
  We study polar coding for stochastic processes with memory. For example, a
process may be defined by the joint distribution of the input and output of a
channel. The memory may be present in the channel, the input, or both. We show
that $\psi$-mixing processes polarize under the standard Ar\i{}kan transform,
under a mild condition. We further show that the rate of polarization of the
\emph{low-entropy} synthetic channels is roughly $O(2^{-\sqrt{N}})$, where $N$
is the blocklength. That is, essentially the same rate as in the memoryless
case.


title:
Identifying the Major Sources of Variance in Transaction Latencies:
  Towards More Predictable Databases

abstract:
  Decades of research have sought to improve transaction processing performance
and scalability in database management systems (DBMSs). However, significantly
less attention has been dedicated to the predictability of performance: how
often individual transactions exhibit execution latency far from the mean?
Performance predictability is vital when transaction processing lies on the
critical path of a complex enterprise software or an interactive web service,
as well as in emerging database-as-a-service markets where customers contract
for guaranteed levels of performance. In this paper, we take several steps
towards achieving more predictable database systems. First, we propose a
profiling framework called VProfiler that, given the source code of a DBMS, is
able to identify the dominant sources of variance in transaction latency.
VProfiler automatically instruments the DBMS source code to deconstruct the
overall variance of transaction latencies into variances and covariances of the
execution time of individual functions, which in turn provide insight into the
root causes of variance. Second, we use VProfiler to analyze MySQL and Postgres
- two of the most popular and complex open-source database systems. Our case
studies reveal that the primary causes of variance in MySQL and Postgres are
lock scheduling and centralized logging, respectively. Finally, based on
VProfiler's findings, we further focus on remedying the performance variance of
MySQL by (1) proposing a new lock scheduling algorithm, called Variance-Aware
Transaction Scheduling (VATS), (2) enhancing the buffer pool replacement
policy, and (3) identifying tuning parameters that can reduce variance
significantly. Our experimental results show that our schemes reduce overall
transaction latency variance by 37% on average (and up to 64%) without
compromising throughput or mean latency.


title: Photoacoustic imaging taking into account thermodynamic attenuation

abstract:
  In this paper we consider a mathematical model for photoacoustic imaging
which takes into account attenuation due to thermodynamic dissipation. The
propagation of acoustic (compressional) waves is governed by a scalar wave
equation coupled to the heat equation for the excess temperature. We seek to
recover the initial acoustic profile from knowledge of acoustic measurements at
the boundary.
  We recognize that this inverse problem is a special case of boundary
observability for a thermoelastic system. This leads to the use of
control/observability tools to prove the unique and stable recovery of the
initial acoustic profile in the weak thermoelastic coupling regime. This
approach is constructive, yielding a solvable equation for the unknown acoustic
profile. Moreover, the solution to this reconstruction equation can be
approximated numerically using the conjugate gradient method. If certain
geometrical conditions for the wave speed are satisfied, this approach is
well--suited for variable media and for measurements on a subset of the
boundary. We also present a numerical implementation of the proposed
reconstruction algorithm.


title:
Dispersion of Magnetic Fields in Molecular Clouds. IV - Analysis of
  Interferometry Data

abstract:
  We expand on the dispersion analysis of polarimetry maps toward applications
to interferometry data. We show how the filtering of low-spatial frequencies
can be accounted for within the idealized Gaussian turbulence model, initially
introduced for single-dish data analysis, to recover reliable estimates for
correlation lengths of magnetized turbulence, as well as magnetic field
strengths (plane-of-the-sky component) using the Davis-Chandrasekhar-Fermi
method. We apply our updated technique to TADPOL/CARMA data obtained on W3(OH),
W3 Main, and DR21(OH). For W3(OH) our analysis yields a turbulence correlation
length $\delta\simeq19$ mpc, a ratio of turbulent-to-total magnetic energy
$\left\langle B_{\mathrm{t}}^{2}\right\rangle /\left\langle B^{2}\right\rangle
\simeq0.58$, and a magnetic field strength $B_{0}\sim1.1\:\mathrm{mG}$; for W3
Main $\delta\simeq22$ mpc, $\left\langle B_{\mathrm{t}}^{2}\right\rangle
/\left\langle B^{2}\right\rangle \simeq0.74$, and $B_{0}\sim0.7\:\mathrm{mG}$;
while for DR21(OH) $\delta\simeq12$ mpc, $\left\langle
B_{\mathrm{t}}^{2}\right\rangle /\left\langle B^{2}\right\rangle \simeq0.70$,
and $B_{0}\sim1.2\:\mathrm{mG}$.


title:
Quantum Chaos and Thermalization in Isolated Systems of Interacting
  Particles

abstract:
  This review is devoted to the problem of thermalization in a small isolated
conglomerate of interacting constituents. A variety of physically important
systems of intensive current interest belong to this category: complex atoms,
molecules (including biological molecules), nuclei, small devices of condensed
matter and quantum optics on nano- and micro-scale, cold atoms in optical
lattices, ion traps. Physical implementations of quantum computers, where there
are many interacting qubits, also fall into this group. Statistical
regularities come into play through inter-particle interactions, which have two
fundamental components: mean field, that along with external conditions, forms
the regular component of the dynamics, and residual interactions responsible
for the complex structure of the actual stationary states. At sufficiently high
level density, the stationary states become exceedingly complicated
superpositions of simple quasiparticle excitations. At this stage, regularities
typical of quantum chaos emerge and bring in signatures of thermalization. We
describe all the stages and the results of the processes leading to
thermalization, using analytical and massive numerical examples for realistic
atomic, nuclear, and spin systems, as well as for models with random
parameters. The structure of stationary states, strength functions of simple
configurations, and concepts of entropy and temperature in application to
isolated mesoscopic systems are discussed in detail. We conclude with a
schematic discussion of the time evolution of such systems to equilibrium.


title: Gene Ontology: Pitfalls, Biases, Remedies

abstract:
  The Gene Ontology (GO) is a formidable resource but there are several
considerations about it that are essential to understand the data and interpret
it correctly. The GO is sufficiently simple that it can be used without deep
understanding of its structure or how it is developed, which is both a strength
and a weakness. In this chapter, we discuss some common misinterpretations of
the ontology and the annotations. A better understanding of the pitfalls and
the biases in the GO should help users make the most of this very rich
resource. We also review some of the misconceptions and misleading assumptions
commonly made about GO, including the effect of data incompleteness, the
importance of annotation qualifiers, and the transitivity or lack thereof
associated with different ontology relations. We also discuss several biases
that can confound aggregate analyses such as gene enrichment analyses. For each
of these pitfalls and biases, we suggest remedies and best practices.


title: Primer on the Gene Ontology

abstract:
  The Gene Ontology (GO) project is the largest resource for cataloguing gene
function. The combination of solid conceptual underpinnings and a practical set
of features have made the GO a widely adopted resource in the research
community and an essential resource for data analysis. In this chapter, we
provide a concise primer for all users of the GO. We briefly introduce the
structure of the ontology and explain how to interpret annotations associated
with the GO.


title: Seeing Through the Ring: Near-Infrared Photometry of V582 Mon (KH 15D)

abstract:
  We examine the light and color evolution of the T Tauri binary KH 15D through
photometry obtained at wavelengths between 0.55 and 8.0 $\mu$m. The data were
collected with ANDICAM on the 1.3 m SMARTS telescope at Cerro-Tololo
Inter-American Observatory and with IRAC on the Spitzer Space Telescope. We
show that the system's circumbinary ring, which acts as a screen that covers
and uncovers different portions of the binary orbit as the ring precesses, has
reached an orientation where the brighter component (star B) fully or nearly
fully emerges during each orbital cycle. The fainter component (star A) remains
fully occulted by the screen at all phases. The leading and trailing edges of
the screen move across the sky at the same rate of $\sim$15 meters per second,
consistent with expectation for a ring with a radius and width of $\sim$4 AU
and a precession period of $\sim$6500 years. Light and color variations
continue to indicate that the screen is sharp edged and opaque at \emph{VRIJH}
wavelengths. However, we find an increasing transparency of the ring edge at
2.2, 3.6, and 4.5 $\mu$m. Reddening seen at the beginning of the eclipse that
occurred during the CSI 2264 campaign particularly suggests selective
extinction by a population of large dust grains. Meanwhile, the gradual bluing
observed while star B is setting is indicative of forward scattering effects at
the edge of the ring. The SED of the system at its bright phase shows no
evidence of infrared excess emission that can be attributed to radiation from
the ring or other dust component out to 8 microns.


title:
On the microscopic origin and macroscopic implications of lane formation
  in mixtures of oppositely-driven particles

abstract:
  Colloidal particles of two types, driven in opposite directions, can
segregate into lanes [Vissers et al. Soft Matter 7, 2352 (2011)]. This
phenomenon can be reproduced by two-dimensional Brownian dynamics simulations
of model particles [Dzubiella et al. Phys. Rev. E 65, 021402 (2002)]. Here we
use computer simulation to assess the generality of lane formation with respect
to variation of particle type and dynamical protocol. We find that laning
results from rectification of diffusion on the scale of a particle diameter:
oppositely-driven particles must, in the time taken to encounter each other in
the direction of the drive, diffuse in the perpendicular direction by about one
particle diameter. This geometric constraint implies that the diffusion
constant of a particle, in the presence of those of the opposite type, grows
approximately linearly with Peclet number, a prediction confirmed by our
numerics over a range of model parameters. Such environment-dependent diffusion
is statistically similar to an effective interparticle attraction; consistent
with this observation, we find that oppositely-driven non-attractive colloids
display features characteristic of the simplest model system possessing both
interparticle attractions and persistent motion, the driven Ising lattice gas
[Katz, Leibowitz, Spohn, J. Stat. Phys. 34, 497 (1984)]. These features include
long-ranged correlations in the disordered regime, and a critical regime
characterized by a change in slope of the particle current with Peclet number
and by fluctuations that grow with system size. By analogy, we suggest that
lane formation in the driven colloid system is in the macroscopic limit a phase
transition, but that macroscopic phase separation would not occur in finite
time upon starting from disordered initial conditions.


title:
Geometric constants for quantifying the difference between orthogonality
  types

abstract:
  This paper is devoted to introduce new geometric constants that quantify the
difference between Roberts orthogonality and Birkhoff orthogonality in normed
planes. We start by characterizing Roberts orthogonality in two different ways:
via bisectors of two points and using certain linear transformations. Each of
these characterizations yields one of those geometric constants that we will
study.


title: Distinguished theta representations for certain covering groups

abstract:
  For Brylinski-Deligne covering groups of an arbitrary split reductive group,
we consider theta representations attached to certain exceptional genuine
characters. The goal of the paper is to determine when a theta representation
has exactly a one-dimensional space of Whittaker functionals, in which case it
is called distinguished. For this purpose, we first give effective lower and
upper bounds for the dimension of Whittaker functionals for general theta
representations. As a consequence, the dimension in many cases can be reduced
to simple combinatorial computations, e.g., the Kazhdan-Patterson covering
groups, or covering groups whose complex dual group is of adjoint type. In the
second part of the paper, we consider covering groups of certain
simply-connected groups and give necessary and sufficient condition for the
theta representation to be distinguished. There are subtleties arising from the
relation between the rank and the degree of the covering group. However, in
each case we will determine the exceptional character such that its associated
theta representation is distinguished.


title:
Solo Dwarfs I: Survey introduction and first results for the Sagittarius
  Dwarf Irregular Galaxy

abstract:
  We introduce the Solitary Local Dwarfs Survey (Solo), a wide field
photometric study targeting every isolated dwarf galaxy within 3 Mpc of the
Milky Way. Solo is based on (u)gi multi-band imaging from CFHT/MegaCam for
northern targets, and Magellan/Megacam for southern targets. All galaxies
fainter than Mv = -18 situated beyond the nominal virial radius of the Milky
Way and M31 (>300 kpc) are included in this volume-limited sample, for a total
of 42 targets. In addition to reviewing the survey goals and strategy, we
present results for the Sagittarius Dwarf Irregular Galaxy (Sag DIG), one of
the most isolated, low mass galaxies, located at the edge of the Local Group.
We analyze its resolved stellar populations and their spatial distributions. We
provide updated estimates of its central surface brightness and integrated
luminosity, and trace its surface brightness profile to a level fainter than 30
mag./sq.arcsec. Sag DIG is well described by a highly elliptical (disk-like)
system following a single component Sersic model. However, a low-level
distortion is present at the outer edges of the galaxy that, were Sag DIG not
so isolated, would likely be attributed to some kind of previous tidal
interaction. Further, we find evidence of an extremely low level, extended
distribution of stars beyond 5 arcmins (>1.5 kpc) that suggests Sag DIG may be
embedded in a very low density stellar halo. We compare the stellar and HI
structures of Sag DIG, and discuss results for this galaxy in relation to other
isolated, dwarf irregular galaxies in the Local Group.


title:
Double scattering contribution to small-x processes: Mueller-Navelet
  jets at the LHC

abstract:
  We study the importance of double parton scattering (DPS) in Mueller-Navelet
jets production at the LHC. We evaluate this contribution in kinematics
corresponding to existing and possible future measurements at the LHC, for the
cross section and the azimuthal correlation of the jets.


title:
Diagnosis and Repair for Synthesis from Signal Temporal Logic
  Specifications

abstract:
  We address the problem of diagnosing and repairing specifications for hybrid
systems formalized in signal temporal logic (STL). Our focus is on the setting
of automatic synthesis of controllers in a model predictive control (MPC)
framework. We build on recent approaches that reduce the controller synthesis
problem to solving one or more mixed integer linear programs (MILPs), where
infeasibility of a MILP usually indicates unrealizability of the controller
synthesis problem. Given an infeasible STL synthesis problem, we present
algorithms that provide feedback on the reasons for unrealizability, and
suggestions for making it realizable. Our algorithms are sound and complete,
i.e., they provide a correct diagnosis, and always terminate with a non-trivial
specification that is feasible using the chosen synthesis method, when such a
solution exists. We demonstrate the effectiveness of our approach on the
synthesis of controllers for various cyber-physical systems, including an
autonomous driving application and an aircraft electric power system.


title: A 20-Liter Test Stand with Gas Purification for Liquid Argon Research

abstract:
  We describe the design of a 20-liter test stand constructed to study
fundamental properties of liquid argon (LAr). This system utilizes a simple,
cost-effective gas argon (GAr) purification to achieve high purity, which is
necessary to study electron transport properties in LAr. An electron drift
stack with up to 25 cm length is constructed to study electron drift,
diffusion, and attachment at various electric fields. A gold photocathode and a
pulsed laser are used as a bright electron source. The operational performance
of this system is reported.


title:
Picosecond electric-field-induced threshold switching in phase-change
  materials

abstract:
  Many chalcogenide glasses undergo a breakdown in electronic resistance above
a critical field strength. Known as threshold switching, this mechanism enables
field-induced crystallization in emerging phase-change memory. Purely
electronic as well as crystal nucleation assisted models have been employed to
explain the electronic breakdown. Here, picosecond electric pulses are used to
excite amorphous Ag$_4$In$_3$Sb$_{67}$Te$_{26}$. Field-dependent reversible
changes in conductivity and pulse-driven crystallization are observed. The
present results show that threshold switching can take place within the
electric pulse on sub-picosecond time-scales - faster than crystals can
nucleate. This supports purely electronic models of threshold switching and
reveals potential applications as an ultrafast electronic switch.


title: Variational Perspective on Local Graph Clustering

abstract:
  Modern graph clustering applications require the analysis of large graphs and
this can be computationally expensive. In this regard, local spectral graph
clustering methods aim to identify well-connected clusters around a given "seed
set" of reference nodes without accessing the entire graph. The celebrated
Approximate Personalized PageRank (APPR) algorithm in the seminal paper by
Andersen et al. is one such method. APPR was introduced and motivated purely
from an algorithmic perspective. In other words, there is no a priori notion of
objective function/optimality conditions that characterizes the steps taken by
APPR. Here, we derive a novel variational formulation which makes explicit the
actual optimization problem solved by APPR. In doing so, we draw connections
between the local spectral algorithm of and an iterative shrinkage-thresholding
algorithm (ISTA). In particular, we show that, appropriately initialized ISTA
applied to our variational formulation can recover the sought-after local
cluster in a time that only depends on the number of non-zeros of the optimal
solution instead of the entire graph. In the process, we show that an
optimization algorithm which apparently requires accessing the entire graph,
can be made to behave in a completely local manner by accessing only a small
number of nodes. This viewpoint builds a bridge across two seemingly disjoint
fields of graph processing and numerical optimization, and it allows one to
leverage well-studied, numerically robust, and efficient optimization
algorithms for processing today's large graphs.


title: Visual Tracking via Reliable Memories

abstract:
  In this paper, we propose a novel visual tracking framework that
intelligently discovers reliable patterns from a wide range of video to resist
drift error for long-term tracking tasks. First, we design a Discrete Fourier
Transform (DFT) based tracker which is able to exploit a large number of
tracked samples while still ensures real-time performance. Second, we propose a
clustering method with temporal constraints to explore and memorize consistent
patterns from previous frames, named as reliable memories. By virtue of this
method, our tracker can utilize uncontaminated information to alleviate
drifting issues. Experimental results show that our tracker performs favorably
against other state of-the-art methods on benchmark datasets. Furthermore, it
is significantly competent in handling drifts and able to robustly track
challenging long videos over 4000 frames, while most of others lose track at
early frames.


title:
Construction of Nano-Assembled Microcapsules Embedded with Gold
  Nanoparticles for use in Novel Drug Delivery Systems

abstract:
  Coronary stents have changed the way in which coronary artery diseases are
managed. Although bare-metal stents can be traced back to 1994, long term
efficacy of these stents has been shattered by ISR (In-Stent restenosis) and
late stent thrombosis. Research on finding a solution to these issues has led
to the development of DESs (Drug eluting stents). However long term
effectiveness of DESs and various drug delivery systems have raised concerns.
Also current DESs does not have the capability to adjust the drug dose or
release kinetics that corresponds to the diseased status of the affected
vessel. Through the use of a drug delivery system which employs controlled drug
release, it may be possible to control the release rate of the pharmacological
drugs or substances of interest, and therefore one might be able to circumvent
the range of events that leads to ISR, thus preventing the need for further
invasive interventions. To overcome the limitations of drug delivery systems,
the administration of drugs using nanoparticle based microcapsules as carriers
is being researched for their ability to facilitate a sustained, prolonged and
controlled release of drugs. But still much research is needed to evaluate and
fix issues relating toxicity, chemical and mechanical properties of the
nanoparticles. This project combines a range of nanobiotechnological techniques
to synthesise nano-components which are finally assembled together to get the
microcapsules which could be used in drug delivery systems. The microcapsules
were engineered keeping in mind their potential use in an ultrasound based drug
delivery system.

categories: physics.med-ph cond-mat.mtrl-sci physics.bio-ph physics.chem-ph q-bio.BM


title:
Discovering Neuronal Cell Types and Their Gene Expression Profiles Using
  a Spatial Point Process Mixture Model

abstract:
  Cataloging the neuronal cell types that comprise circuitry of individual
brain regions is a major goal of modern neuroscience and the BRAIN initiative.
Single-cell RNA sequencing can now be used to measure the gene expression
profiles of individual neurons and to categorize neurons based on their gene
expression profiles. While the single-cell techniques are extremely powerful
and hold great promise, they are currently still labor intensive, have a high
cost per cell, and, most importantly, do not provide information on spatial
distribution of cell types in specific regions of the brain. We propose a
complementary approach that uses computational methods to infer the cell types
and their gene expression profiles through analysis of brain-wide single-cell
resolution in situ hybridization (ISH) imagery contained in the Allen Brain
Atlas (ABA). We measure the spatial distribution of neurons labeled in the ISH
image for each gene and model it as a spatial point process mixture, whose
mixture weights are given by the cell types which express that gene. By fitting
a point process mixture model jointly to the ISH images, we infer both the
spatial point process distribution for each cell type and their gene expression
profile. We validate our predictions of cell type-specific gene expression
profiles using single cell RNA sequencing data, recently published for the
mouse somatosensory cortex. Jointly with the gene expression profiles, cell
features such as cell size, orientation, intensity and local density level are
inferred per cell type.


title:
Search Tracker: Human-derived object tracking in-the-wild through
  large-scale search and retrieval

abstract:
  Humans use context and scene knowledge to easily localize moving objects in
conditions of complex illumination changes, scene clutter and occlusions. In
this paper, we present a method to leverage human knowledge in the form of
annotated video libraries in a novel search and retrieval based setting to
track objects in unseen video sequences. For every video sequence, a document
that represents motion information is generated. Documents of the unseen video
are queried against the library at multiple scales to find videos with similar
motion characteristics. This provides us with coarse localization of objects in
the unseen video. We further adapt these retrieved object locations to the new
video using an efficient warping scheme. The proposed method is validated on
in-the-wild video surveillance datasets where we outperform state-of-the-art
appearance-based trackers. We also introduce a new challenging dataset with
complex object appearance changes.


title:
Distributed Estimation of State and Parameters in Multi-Agent
  Cooperative Load Manipulation

abstract:
  We present two distributed methods for the estimation of the kinematic
parameters, the dynamic parameters, and the kinematic state of an unknown
planar body manipulated by a decentralized multi-agent system. The proposed
approaches rely on the rigid body kinematics and dynamics, on nonlinear
observation theory, and on consensus algorithms. The only three requirements
are that each agent can exert a 2D wrench on the load, it can measure the
velocity of its contact point, and that the communication graph is connected.
Both theoretical nonlinear observability analysis and convergence proofs are
provided. The first method assumes constant parameters while the second one can
deal with time-varying parameters and can be applied in parallel to any
task-oriented control law. For the cases in which a control law is not
provided, we propose a distributed and safe control strategy satisfying the
observability condition. The effectiveness and robustness of the estimation
strategy is showcased by means of realistic MonteCarlo simulations.


title: Structural stability of Supersonic solutions to the Euler-Poisson system

abstract:
  The well-posedness for the supersonic solutions of the Euler-Poisson system
for hydrodynamical model in semiconductor devices and plasmas is studied in
this paper. We first reformulate the Euler-Poisson system in the supersonic
region into a second order hyperbolic-elliptic coupled system together with
several transport equations. One of the key ingredients of the analysis is to
obtain the well-posedness of the boundary value problem for the associated
linearized hyperbolic-elliptic coupled system, which is achieved via a delicate
choice of multiplier to gain energy estimate. The nonlinear structural
stability of supersonic solution in the general situation is established by
combining the iteration method with the estimate for hyperbolic-elliptic system
and the transport equations together.


title: What is absolutely continuous spectrum?

abstract:
  This note is an expanded version of the author's contribution to the
Proceedings of the ICMP Santiago, 2015, and is based on a talk given by the
second author at the same Congress. It concerns a research program devoted to
the characterization of the absolutely continuous spectrum of a self-adjoint
operator H in terms of the transport properties of a suitable class of open
quantum systems canonically associated to H.

categories: math-ph cond-mat.stat-mech math.MP quant-ph


title:
Databases of elliptic curves ordered by height and distributions of
  Selmer groups and ranks

abstract:
  Most systematic tables of data associated to ranks of elliptic curves order
the curves by conductor. Recent developments, led by work of Bhargava-Shankar
studying the average sizes of $n$-Selmer groups, have given new upper bounds on
the average algebraic rank in families of elliptic curves over $\mathbb{Q}$
ordered by height. We describe databases of elliptic curves over $\mathbb{Q}$
ordered by height in which we compute ranks and $2$-Selmer group sizes, the
distributions of which may also be compared to these theoretical results. A
striking new phenomenon observed in these databases is that the average rank
eventually decreases as height increases.


title:
Generate Image Descriptions based on Deep RNN and Memory Cells for
  Images Features

abstract:
  Generating natural language descriptions for images is a challenging task.
The traditional way is to use the convolutional neural network (CNN) to extract
image features, followed by recurrent neural network (RNN) to generate
sentences. In this paper, we present a new model that added memory cells to
gate the feeding of image features to the deep neural network. The intuition is
enabling our model to memorize how much information from images should be fed
at each stage of the RNN. Experiments on Flickr8K and Flickr30K datasets showed
that our model outperforms other state-of-the-art models with higher BLEU
scores.


title: Catcher-Evader Games

abstract:
  Algorithms for computing game-theoretic solutions have recently been applied
to a number of security domains. However, many of the techniques developed for
compact representations of security games do not extend to {\em Bayesian}
security games, which allow us to model uncertainty about the attacker's type.
In this paper, we introduce a general framework of {\em catcher-evader} games
that can capture Bayesian security games as well as other game families of
interest. We show that computing Stackelberg strategies is NP-hard, but give an
algorithm for computing a Nash equilibrium that performs well in experiments.
We also prove that the Nash equilibria of these games satisfy the {\em
interchangeability} property, so that equilibrium selection is not an issue.


title:
Ca II triplet spectroscopy of RGB stars in NGC 6822: kinematics and
  metallicities

abstract:
  We present a detailed analysis of the chemistry and kinematics of red giants
in the dwarf irregular galaxy NGC 6822. Spectroscopy at 8500 Angstroms was
acquired for 72 red giant stars across two fields using FORS2 at the VLT. Line
of sight extinction was individually estimated for each target star to
accommodate the variable reddening across NGC 6822. The mean radial velocity
was found to be v_helio = (52.8 +/- 2.2) km/s with dispersion rms = 24.1 km/s,
in agreement with other studies. Ca II triplet equivalent widths were converted
into [Fe/H] metallicities using a V magnitude proxy for surface gravity. The
average metallicity was [Fe/H] = (-0.84 +/- 0.04) with dispersion rms = 0.31
dex and interquartile range 0.48. Our assignment of individual reddening values
makes our analysis more sensitive to spatial variations in metallicity than
previous studies. We divide our sample into metal-rich and metal-poor stars;
the former are found to cluster towards small radii with the metal-poor stars
more evenly distributed across the galaxy. The velocity dispersion of the
metal-poor stars is higher than that of the metal-rich stars; combined with the
age-metallicity relation this indicates that older populations have either been
dynamically heated or were born in a less disclike distribution. The low ratio
(v_rot/v_rms) suggests that within the inner 10', NGC 6822's stars are
dynamically decoupled from the HI gas, possibly in a thick disc or spheroid.


title:
Simulation of the Efficiency of CdS/CIGS Tandem Multi-Junction Solar
  Cells Using AMPS-1D

abstract:
  In this paper we conduct numerical simulation of CdS/CIGS solar cells by use
of the AMPS-1D software aiming to formulate the optimal design of the new
multi-junction tandem solar cell providing its most efficient operation. We
start with the numerical simulation of single-junction CdS/CIGS solar cells,
which shows that its highest efficiency of 17.3% could be achieved by the
thickness of CIGS p-layer of 200 nm. This result is in a good agreement with
experimental data where the highest efficiency was 17.1% with the solar cell
thickness of 1 micron. By use of the results of the numerical simulation of the
single-junction solar cells we developed the design and conducted optimization
of the new multi-junction tandem CdS/CIGS solar cell structure. Numerical
simulation shows that the maximum efficiency of this solar cell is equal to
48.3%, which could be obtained with the thickness of the CIGS p-layer of 600 nm
at a standard illumination of AM 1.5.


title: Temporal Evolution of the Vela Pulsar's Pulse Profile

abstract:
  The mechanisms of emission and changes in rotation frequency ('glitching') of
the Vela pulsar (J0835-4510) are not well understood. Further insight into
these mechanisms can be achieved by long-term studies of integrated pulse
width, timing residuals, and bright pulse rates. We have undertaken an
intensive observing campaign of Vela and collected over 6000 hours of single
pulse data. The data shows that the pulse width changes with time, including
marked jumps in width after micro-glitches (frequency changes). The abundance
of bright pulses also changes after some micro-glitches, but not all. The
secular changes in pulse width have three possible cyclic periods, that match
with X-ray periodicities of a helical jet that are interpreted as free
precession.


title:
Volume-preserving maps between Hermitian symmetric spaces of compact
  type

abstract:
  In this paper, we establish the rigidity result for local holomorphic volume
preserving maps from an irreducible Hermitian manifold of compact type into its
Cartesian products.


title:
New Pleiades Eclipsing Binaries and a Hyades Transiting System
  Identified by K2

abstract:
  We present the discovery in Kepler's $K2$ mission observations and our
follow-up radial velocity observations from Keck/HIRES for four eclipsing
binary (EB) star systems in the young benchmark Pleiades cluster. Based on our
modeling results, we announce two new low mass ($M_{tot} < 0.6 M_\odot$) EBs
among Pleiades members (HCG 76 and MHO 9) and we report on two previously known
Pleiades binaries that are also found to be EB systems (HII 2407 and HD 23642).
We measured the masses of the binary HCG 76 to $\lesssim$2.5% precision, and
the radii to $\lesssim$4.5% precision, which together with the precise
effective temperatures yield an independent Pleiades distance of 132$\pm$5 pc.
We discuss another EB towards the Pleiades that is a possible but unlikely
Pleiades cluster member (AK II 465). The two new confirmed Pleiades systems
extend the mass range of Pleiades EB components to 0.2-2 $M_\odot$. Our initial
measurements of the fundamental stellar parameters for the Pleiades EBs are
discussed in the context of the current stellar models and the nominal cluster
isochrone, finding good agreement with the stellar models of Baraffe et al.
(2015) at the nominal Pleiades age of 120 Myr.
  Finally, in the Hyades, we report a new low mass eclipsing system (vA 50)
that was concurrently discovered and studied by Mann et al. (2016). We confirm
that the eclipse is likely caused by a Neptune-sized transiting planet, and
with the additional radial velocity constraints presented here we improve the
constraint on the maximum mass of the planet to be $\lesssim$1.2
$M_\mathrm{Jup}$.


title: Sharp pointwise estimates for functions in the Sobolev spaces Hs(Rn)

abstract:
  We obtain the optimal value of the constant K(n,s) in the
Sobolev-Nirenberg-Gagliardo inequality $ \|\,u\,\|_{L^{\infty}(\mathbb{R}^{n})}
\leq K(n,s) \,\|\, u \,\|_{L^{2}(\mathbb{R}^{n})}^{1 - n/(2s)} \|\, u
\,\|_{\dot{H}^{s}(\mathbb{R}^{n})}^{n/(2s)} $ where $ s > n/2 $.


title: A double-inductive proof of Moessner's theorem

abstract:
  We present a proof of Moessner's theorem by double induction, using only
basic rules of arithmetic. No prerequisite knowledge is assumed. Familiarity
with summation is advised.


title: On the Discovery of Success Trajectories of Authors

abstract:
  Understanding the qualitative patterns of research endeavor of scientific
authors in terms of publication count and their impact (citation) is important
in order to quantify success trajectories. Here, we examine the career profile
of authors in computer science and physics domains and discover at least six
different success trajectories in terms of normalized citation count in
longitudinal scale. Initial observations of individual trajectories lead us to
characterize the authors in each category. We further leverage this trajectory
information to build a two-stage stratification model to predict future success
of an author at the early stage of her career. Our model outperforms the
baseline with an average improvement of 15.68% for both the datasets.


title: Dissipation in small systems: A Landau-Zener approach

abstract:
  We establish a stochastic thermodynamics for a Fermionic level driven by a
time-dependent force and interacting with initially thermalized levels playing
the role of a reservoir. The driving induces consecutive avoided crossings
between system and reservoir levels described within Landau-Zener theory. We
derive the resulting system dynamics and thermodynamics and identify energy,
work, heat, entropy and dissipation. Our theory perfectly reproduces the
numerically exact quantum work statistics obtained using a two point
measurements approach of the total energy and provides an explicit expression
for the dissipation in terms of diabatic transitions.


title: Selecting wavelengths for least squares range estimation

abstract:
  We consider the problem of estimating the distance, or range, between two
locations by measuring the phase of multiple sinusoidal signals transmitted
between the locations. Traditional estimators developed for optical
interferometry include the beat wavelength and excess fractions methods. More
recently, estimators based on the Chinese remainder theorem (CRT) and least
squares have appeared. Recent research suggests the least squares estimator to
be most accurate in many cases. The accuracy of all of these range estimators
depends upon the wavelengths chosen. This leads to the problem of selecting
wavelengths that maximise accuracy. Procedures for selecting wavelengths for
the beat wavelength and excess fractions methods have previously been
described, but procedures for the CRT and least squares estimators are yet to
be developed. In this paper we develop an algorithm to automatically select
wavelengths for use with the least square range estimator. The algorithm
minimises an optimisation criterion connected with the mean square error.
Interesting properties of a particular class of lattices simplify the criterion
allowing minimisation by depth first search. Monte-Carlo simulations indicate
that wavelengths that minimise the criterion can result is considerably more
accurate range estimates than wavelengths selected by ad hoc means.


title: What does it take to see entanglement?

abstract:
  Tremendous progress has been realized in quantum optics for engineering and
detecting the quantum properties of light. Today, photon pairs are routinely
created in entangled states. Entanglement is revealed using single-photon
detectors in which a single photon triggers an avalanche current. The resulting
signal is then processed and stored in a computer. Here, we propose an approach
to get rid of all the electronic devices between the photons and the
experimentalist i.e. to use the experimentalist's eye to detect entanglement.
We show in particular, that the micro entanglement that is produced by sending
a single photon into a beam-splitter can be detected with the eye using the
magnifying glass of a displacement in phase space. The feasibility study
convincingly demonstrates the possibility to realize the first experiment where
entanglement is observed with the eye.


title: ASEP(q,j) converges to the KPZ equation

abstract:
  We show that a generalized Asymmetric Exclusion Process called ASEP(q,j)
introduced by Carinci, Giardina, Redig and Sasamoto converges to the Cole-Hopf
solution to the KPZ equation under weak asymmetry scaling.


title: Modelling the flare activity of Sgr A*

abstract:
  Latest observational data provides evidence that the emissions from Sgr A*
originate from an accretion disc within ten gravitational radii of the
dynamical centre of Milky Way. We investigate the physical processes
responsible for the variable observed emissions from the compact radio source
Sgr A*. We study the evolution of the variable emission region and analyse
light curves and time-resolved spectra of emissions originated at the surface
of the accretion disk, close to the event horizon, near the marginally stable
orbit of a Kerr black hole.


title:
Fast Multiplier Methods to Optimize Non-exhaustive, Overlapping
  Clustering

abstract:
  Clustering is one of the most fundamental and important tasks in data mining.
Traditional clustering algorithms, such as K-means, assign every data point to
exactly one cluster. However, in real-world datasets, the clusters may overlap
with each other. Furthermore, often, there are outliers that should not belong
to any cluster. We recently proposed the NEO-K-Means (Non-Exhaustive,
Overlapping K-Means) objective as a way to address both issues in an integrated
fashion. Optimizing this discrete objective is NP-hard, and even though there
is a convex relaxation of the objective, straightforward convex optimization
approaches are too expensive for large datasets. A practical alternative is to
use a low-rank factorization of the solution matrix in the convex formulation.
The resulting optimization problem is non-convex, and we can locally optimize
the objective function using an augmented Lagrangian method. In this paper, we
consider two fast multiplier methods to accelerate the convergence of an
augmented Lagrangian scheme: a proximal method of multipliers and an
alternating direction method of multipliers (ADMM). For the proximal augmented
Lagrangian or proximal method of multipliers, we show a convergence result for
the non-convex case with bound-constrained subproblems. These methods are up to
13 times faster---with no change in quality---compared with a standard
augmented Lagrangian method on problems with over 10,000 variables and bring
runtimes down from over an hour to around 5 minutes.


title:
An Achievable Rate-Distortion Region for Multiple Descriptions Source
  Coding Based on Coset Codes

abstract:
  We consider the problem of multiple descriptions (MD) source coding and
propose new coding strategies involving both unstructured and structured coding
layers. Previously, the most general achievable rate-distortion (RD) region for
the $l$-descriptions problem was the Combinatorial Message Sharing with Binning
(CMSB) region. The CMSB scheme utilizes unstructured quantizers and
unstructured binning. In the first part of the paper, we show that this
strategy can be improved upon using more general unstructured quantizers and a
more general unstructured binning method. In the second part, structured coding
strategies are considered. First, structured coding strategies are developed by
considering specific MD examples involving three or more descriptions. We show
that application of structured quantizers results in strict RD improvements
when there are more than two descriptions. Furthermore, we show that structured
binning also yields improvements. These improvements are in addition to the
ones derived in the first part of the paper. This suggests that structured
coding is essential when coding over more than two descriptions. Using the
ideas developed through these examples we provide a new unified coding strategy
by considering several structured coding layers. Finally, we characterize its
performance in the form of an inner bound to the optimal rate-distortion region
using computable single-letter information quantities. The new RD region
strictly contains all of the previous known achievable regions.


title:
Living with a Red Dwarf: Rotation and X-ray and Ultraviolet Properties
  of the Halo Population Kapteyn's Star

abstract:
  As part of Villanova's Living with a Red Dwarf program, we have obtained UV,
X-ray and optical data of the Population II red dwarf -- Kapteyn's Star.
Kapteyn's Star is noteworthy for its large proper motions and high RV of ~+245
km s^-1. As the nearest Pop II red dwarf, it serves as an old age anchor for
calibrating Activity/Irradiance-Rotation-Age relations, and an important test
bed for stellar dynamos and the resulting X-ray -- UV emissions of slowly
rotating, near-fully convective red dwarf stars. Adding to the notoriety,
Kapteyn's Star has recently been reported to host two super-Earth candidates,
one of which (Kapteyn b) is orbiting within the habitable zone (Anglada-Escude
et al. 2014a, 2015). However, Robertson et al. (2015) questioned the planet's
existence since its orbital period may be an artifact of activity, related to
the star's rotation period. Because of its large Doppler-shift, measures of the
important, chromospheric H I Lyman-alpha 1215.67A emission line can be reliably
made, because it is mostly displaced from ISM and geo-coronal sources.
Lyman-alpha emission dominates the FUV region of cool stars. Our measures can
help determine the X-ray--UV effects on planets hosted by Kapteyn's Star, and
planets hosted by other old red dwarfs. Stellar X-ray and Lyman-alpha emissions
have strong influences on the heating and ionization of upper planetary
atmospheres and can (with stellar winds and flares) erode or even eliminate
planetary atmospheres. Using our program stars, we have reconstructed the past
exposures of Kapteyn's Star's planets to coronal -- chromospheric XUV emissions
over time.


title:
Effective Clipart Image Vectorization Through Direct Optimization of
  Bezigons

abstract:
  Bezigons, i.e., closed paths composed of B\'ezier curves, have been widely
employed to describe shapes in image vectorization results. However, most
existing vectorization techniques infer the bezigons by simply approximating an
intermediate vector representation (such as polygons). Consequently, the
resultant bezigons are sometimes imperfect due to accumulated errors, fitting
ambiguities, and a lack of curve priors, especially for low-resolution images.
In this paper, we describe a novel method for vectorizing clipart images. In
contrast to previous methods, we directly optimize the bezigons rather than
using other intermediate representations; therefore, the resultant bezigons are
not only of higher fidelity compared with the original raster image but also
more reasonable because they were traced by a proficient expert. To enable such
optimization, we have overcome several challenges and have devised a
differentiable data energy as well as several curve-based prior terms. To
improve the efficiency of the optimization, we also take advantage of the local
control property of bezigons and adopt an overlapped piecewise optimization
strategy. The experimental results show that our method outperforms both the
current state-of-the-art method and commonly used commercial software in terms
of bezigon quality.


title: The ATLAS-SPT Radio Survey of Cluster Galaxies

abstract:
  Using a high-performance computing cluster to mosaic 4,787 pointings, we have
imaged the 100 sq. deg. South Pole Telescope (SPT) deep-field at 2.1 GHz using
the Australian Telescope Compact Array to an rms of 80 $\mu$Jy and a resolution
of 8". Our goal is to generate an independent sample of radio-selected galaxy
clusters to study how the radio properties compare with cluster properties at
other wavelengths, over a wide range of redshifts in order to construct a
timeline of their evolution out to $z \sim 1.3$. A preliminary analysis of the
source catalogue suggests there is no spatial correlation between the clusters
identified in the SPT-SZ catalogue and our wide-angle tail galaxies.


title:
Clustering action potential spikes: Insights on the use of overfitted
  finite mixture models and Dirichlet process mixture models

abstract:
  The modelling of action potentials from extracellular recordings, or spike
sorting, is a rich area of neuroscience research in which latent variable
models are often used. Two such models, Overfitted Finite Mixture models (OFMs)
and Dirichlet Process Mixture models (DPMs) are considered to provide insights
for unsupervised clustering of complex, multivariate medical data when the
number of clusters is unknown. OFM and DPM are structured in a similar
hierarchical fashion but they are based on different philosophies with
different underlying assumptions. This study investigates how these differences
impact on a real study of spike sorting, for the estimation of multivariate
Gaussian location-scale mixture models in the presence of common difficulties
arising from complex medical data. The results provide insights allowing the
future analyst to choose an approach suited to the situation and goal of the
research problem at hand.