title: Star formation triggered by galaxy interactions in modified gravity

abstract:
  Together with interstellar turbulence, gravitation is one key player in star
formation. It acts both at galactic scales in the assembly of gas into dense
clouds, and inside those structures for their collapse and the formation of
pre-stellar cores. To understand to what extent the large scale dynamics govern
the star formation activity of galaxies, we present hydrodynamical simulations
in which we generalise the behaviour of gravity to make it differ from
Newtonian dynamics in the low acceleration regime. We focus on the extreme
cases of interacting galaxies, and compare the evolution of galaxy pairs in the
dark matter paradigm to that in the Milgromian Dynamics (MOND) framework.
Following up on the seminal work by Tiret & Combes, this paper documents the
first simulations of galaxy encounters in MOND with a detailed Eulerian
hydrodynamical treatment of baryonic physics, including star formation and
stellar feedback. We show that similar morphologies of the interacting systems
can be produced by both the dark matter and MOND formalisms, but require a much
slower orbital velocity in the MOND case. Furthermore, we find that the star
formation activity and history are significantly more extended in space and
time in MOND interactions, in particular in the tidal debris. Such differences
could be used as observational diagnostics and make interacting galaxies prime
objects in the study of the nature of gravitation at galactic scales.


title:
Unbounded memory advantage in stochastic simulation using quantum
  mechanics

abstract:
  Simulating the stochastic evolution of real quantities on a digital computer
requires a trade-off between the precision to which these quantities are
approximated, and the memory required to store them. The statistical accuracy
of the simulation is thus generally limited by the internal memory available to
the simulator. Here, using tools from computational mechanics, we show that
quantum processors with a fixed finite memory can simulate stochastic processes
of real variables to arbitrarily high precision. This demonstrates a provable,
unbounded memory advantage that a quantum simulator can exhibit over its best
possible classical counterpart.


title:
The Razor's Edge of Collapse: The Transition Point from Lognormal to
  Powerlaw in Molecular Cloud PDFs

abstract:
  We derive an analytic expression for the transitional column density value
($s_t$) between the lognormal and power-law form of the probability
distribution function (PDF) in star-forming molecular clouds. Our expression
for $s_t$ depends on the mean column density, the variance of the lognormal
portion of the PDF, and the slope of the power-law portion of the PDF. We show
that $s_t$ can be related to physical quantities such as the sonic Mach number
of the flow and the power-law index for a self-gravitating isothermal sphere.
This implies that the transition point between the lognormal and power-law
density/column density PDF represents the critical density where turbulent and
thermal pressure balance, the so-called "post-shock density." We test our
analytic prediction for the transition column density using dust PDF
observations reported in the literature as well as numerical MHD simulations of
self-gravitating supersonic turbulence with the Enzo code. We find excellent
agreement between the analytic $s_t$ and the measured values from the numerical
simulations and observations (to within 1.5 A$_V$). We discuss the utility of
our expression for determining the properties of the PDF from unresolved low
density material in dust observations, for estimating the post-shock density,
and for determining the HI-H$_2$ transition in clouds.


title:
On-sky single-mode fiber coupling measurements at the Large Binocular
  Telescope

abstract:
  The demonstration of efficient single-mode fiber (SMF) coupling is a key
requirement for the development of a compact, ultra-precise radial velocity
(RV) spectrograph. iLocater is a next generation instrument for the Large
Binocular Telescope (LBT) that uses adaptive optics (AO) to inject starlight
into a SMF. In preparation for commissioning iLocater, a prototype SMF
injection system was installed and tested at the LBT in the Y-band (0.970-1.065
$\mu$m). This system was designed to verify the capability of the LBT AO system
as well as characterize on-sky SMF coupling efficiencies. SMF coupling was
measured on stars with variable airmasses, apparent magnitudes, and seeing
conditions for six half-nights using the Large Binocular Telescope
Interferometer. We present the overall optical and mechanical performance of
the SMF injection system, including details of the installation and alignment
procedure. A particular emphasis is placed on analyzing the instrument's
performance as a function of telescope elevation to inform the final design of
the fiber injection system for iLocater.


title:
The iLocater cryostat: design and thermal control strategy for precision
  radial velocity measurements

abstract:
  The current generation of precision radial velocity (RV) spectrographs are
seeing-limited instruments. In order to achieve high spectral resolution on 8m
class telescopes, these spectrographs require large optics and in turn, large
instrument volumes. Achieving milli-Kelvin thermal stability for these systems
is challenging but is vital in order to obtain a single measurement RV
precision of better than 1m/s. This precision is crucial to study Earth-like
exoplanets within the habitable zone. iLocater is a next generation RV
instrument being developed for the Large Binocular Telescope. Unlike
seeing-limited RV instruments, iLocater uses adaptive optics (AO) to inject a
diffraction-limited beam into single-mode fibers. These fibers illuminate the
instrument spectrograph, facilitating a diffraction-limited design and a small
instrument volume compared to present-day instruments. This enables intrinsic
instrument stability and facilitates precision thermal control. We present the
current design of the iLocater cryostat which houses the instrument
spectrograph and the strategy for its thermal control. The spectrograph is
situated within a pair of radiation shields mounted inside an MLI lined vacuum
chamber. The outer radiation shield is actively controlled to maintain
instrument stability at the sub-mK level and minimize effects of thermal
changes from the external environment. An inner shield passively dampens any
residual temperature fluctuations and is radiatively coupled to the optical
board. To provide intrinsic stability, the optical board and optic mounts will
be made from Invar and cooled to 58K to benefit from a zero coefficient of
thermal expansion (CTE) value at this temperature. Combined, the small
footprint of the instrument spectrograph, the use of Invar, and precision
thermal control will allow long-term sub-milliKelvin stability to facilitate
precision RV measurements.


title:
iLocater: A Diffraction-limited Doppler Spectrometer for the Large
  Binocular Telescope

abstract:
  We are developing a stable and precise spectrograph for the Large Binocular
Telescope (LBT) named "iLocater." The instrument comprises three principal
components: a cross-dispersed echelle spectrograph that operates in the
YJ-bands (0.97-1.30 microns), a fiber-injection acquisition camera system, and
a wavelength calibration unit. iLocater will deliver high spectral resolution
(R~150,000-240,000) measurements that permit novel studies of stellar and
substellar objects in the solar neighborhood including extrasolar planets.
Unlike previous planet-finding instruments, which are seeing-limited, iLocater
operates at the diffraction limit and uses single mode fibers to eliminate the
effects of modal noise entirely. By receiving starlight from two 8.4m diameter
telescopes that each use "extreme" adaptive optics (AO), iLocater shows promise
to overcome the limitations that prevent existing instruments from generating
sub-meter-per-second radial velocity (RV) precision. Although optimized for the
characterization of low-mass planets using the Doppler technique, iLocater will
also advance areas of research that involve crowded fields, line-blanketing,
and weak absorption lines.


title:
Three-dimensional distribution of ejecta in Supernova 1987A at 10 000
  days

abstract:
  Due to its proximity, SN 1987A offers a unique opportunity to directly
observe the geometry of a stellar explosion as it unfolds. Here we present
spectral and imaging observations of SN 1987A obtained ~10,000 days after the
explosion with HST/STIS and VLT/SINFONI at optical and near-infrared
wavelengths. These observations allow us to produce the most detailed 3D map of
H-alpha to date, the first 3D maps for [Ca II] \lambda \lambda 7292, 7324, [O
I] \lambda \lambda 6300, 6364 and Mg II \lambda \lambda 9218, 9244, as well as
new maps for [Si I]+[Fe II] 1.644 \mu m and He I 2.058 \mu m. A comparison with
previous observations shows that the [Si I]+[Fe II] flux and morphology have
not changed significantly during the past ten years, providing evidence that it
is powered by 44Ti. The time-evolution of H-alpha shows that it is
predominantly powered by X-rays from the ring, in agreement with previous
findings. All lines that have sufficient signal show a similar large-scale 3D
structure, with a north-south asymmetry that resembles a broken dipole. This
structure correlates with early observations of asymmetries, showing that there
is a global asymmetry that extends from the inner core to the outer envelope.
On smaller scales, the two brightest lines, H-alpha and [Si I]+[Fe II] 1.644
\mu m, show substructures at the level of ~ 200 - 1000 km/s and clear
differences in their 3D geometries. We discuss these results in the context of
explosion models and the properties of dust in the ejecta.


title: A convergent $\frac{1}{N}$ expansion for GUE

abstract:
  We show that the asymptotic $1/N$ expansion for the averages of linear
statistics of the GUE is convergent when the test function is an entire
function of order two and finite type. This allows to fully recover the mean
eigenvalue density function for finite $N$ from the coefficients of the
expansion thus providing a resummation procedure. As an intermediate result we
compute the bilateral Laplace transform of the GUE reproducing kernel in the
half-sum variable, generalizing a formula of Haagerup and Thorbj{\o}rnsen.


title:
Fabrication of fully automated setup for high temperature thermal
  conductivity measurement

abstract:
  In this work, we report the fabrication of experimental setup for high
temperature thermal conductivity ($\kappa$) measurement. It can characterize
samples with various dimensions and shapes. Steady state based axial heat flow
technique is used for $\kappa$ measurement. Heat loss is measured using
parallel thermal conductance technique. Simple design, lightweight and small
size sample holder is developed by using a thin heater and limited components.
Low heat loss value is achieved by using very low thermal conductive insulator
block with small cross sectional area. Power delivered to the heater is
measured accurately by using 4-wire technique and for this, heater is developed
with 4-wire. This setup is validated by using $Bi_{0.36}Sb_{1.45}Te_3$,
polycrystalline bismuth, gadolinium, and alumina samples. The data obtained for
these samples are found to be in good agreement with the reported data. The
maximum deviation of 6 \% in the value $\kappa$ are observed. This maximum
deviation is observed with the gadolinium sample. We also report the thermal
conductivity of polycrystalline tellurium from 320 K to 550 K and the non
monotonous behavior of $\kappa$ with temperature is observed.


title: No hydrogen exosphere detected around the super-Earth HD97658 b

abstract:
  The exoplanet HD97658b provides a rare opportunity to probe the atmospheric
composition and evolution of moderately irradiated super-Earths. It transits a
bright K star at a moderate orbital distance of 0.08 au. Its low density is
compatible with a massive steam envelope that could photodissociate at high
altitudes and become observable as escaping hydrogen. Our analysis of 3
transits with HST/STIS at Ly-alpha reveals no such signature, suggesting that
the thermosphere is not hydrodynamically expanding and is subjected to a low
escape of neutral hydrogen (<10^8 g/s at 3 sigma). Using HST Ly-alpha and
Chandra & XMM-Newton observations at different epochs, we find that HD97658 is
a weak and soft X-ray source with signs of chromospheric variability in the
Ly-alpha line core. We determine an average reference for the intrinsic
Ly-alpha line and XUV spectrum of the star, and show that HD97658 b is in mild
conditions of irradiation compared to other known evaporating exoplanets with
an XUV irradiation about 3 times lower than the evaporating warm Neptune GJ436
b. This could be why the thermosphere of HD97658b is not expanding: the low XUV
irradiation prevents an efficient photodissociation of any putative steam
envelope. Alternatively, it could be linked to a low hydrogen content or
inefficient conversion of the stellar energy input. The HD97658 system provides
clues for understanding the stability of low-mass planet atmospheres. Our study
of HD97658 b can be seen as a control experiment of our methodology, confirming
that it does not bias detections of atmospheric escape and underlining its
strength and reliability. Our results show that stellar activity can be
efficiently discriminated from absorption signatures by a transiting exospheric
cloud. They also highlight the potential of observing the upper atmosphere of
small transiting planets to probe their physical and chemical properties


title: An Adaptive Psychoacoustic Model for Automatic Speech Recognition

abstract:
  Compared with automatic speech recognition (ASR), the human auditory system
is more adept at handling noise-adverse situations, including environmental
noise and channel distortion. To mimic this adeptness, auditory models have
been widely incorporated in ASR systems to improve their robustness. This paper
proposes a novel auditory model which incorporates psychoacoustics and
otoacoustic emissions (OAEs) into ASR. In particular, we successfully implement
the frequency-dependent property of psychoacoustic models and effectively
improve resulting system performance. We also present a novel double-transform
spectrum-analysis technique, which can qualitatively predict ASR performance
for different noise types. Detailed theoretical analysis is provided to show
the effectiveness of the proposed algorithm. Experiments are carried out on the
AURORA2 database and show that the word recognition rate using our proposed
feature extraction method is significantly increased over the baseline. Given
models trained with clean speech, our proposed method achieves up to 85.39%
word recognition accuracy on noisy data.


title: Synchronous Lagrangian variational principles in General Relativity

abstract:
  The problem of formulating synchronous variational principles in the context
of General Relativity is discussed. Based on the analogy with classical
relativistic particle dynamics, the existence of variational principles is
pointed out in relativistic classical field theory which are either
asynchronous or synchronous. The historical Einstein-Hilbert and Palatini
variational formulations are found to belong to the first category.
Nevertheless, it is shown that an alternative route exists which permits one to
cast these principles in terms of equivalent synchronous Lagrangian variational
formulations. The advantage is twofold. First, synchronous approaches allow one
to overcome the lack of gauge symmetry of the asynchronous principles. Second,
the property of manifest covariance of the theory is also restored at all
levels, including the symbolic Euler-Lagrange equations, with the variational
Lagrangian density being now identified with a $4-$scalar. As an application, a
joint synchronous variational principle holding both for the non-vacuum
Einstein and Maxwell equations is displayed, with the matter source being
described by means of a Vlasov kinetic treatment.


title:
Inhibitory loop robustly induces anticipated synchronization in neuronal
  microcircuits

abstract:
  We investigate the synchronization properties between two excitatory coupled
neurons in the presence of an inhibitory loop mediated by an interneuron.
Dynamical inhibition together with noise independently applied to each neuron
provide phase diversity in the dynamics of the neuronal motif. We show that the
interplay between the coupling strengths and external noise controls the phase
relations between the neurons in a counter-intuitive way. For a master-slave
configuration (unidirectional coupling) we find that the slave can anticipate
the master, on average, if the slave is subject to the inhibitory feedback. In
this non-usual regime, called anticipated synchronization (AS), the phase of
the post-synaptic neuron is advanced with respect to that of the pre-synaptic
neuron. We also show that the AS regime survives even in the presence of
unbalanced bidirectional excitatory coupling. Moreover, for the symmetric
mutually coupled situation, the neuron that is subject to the inhibitory loop
leads in phase.


title: On a Local Version of the Bak-Sneppen Model

abstract:
  A major difficulty in studying the Bak-Sneppen model is in effectively
comparing it with well-understood models. This stems from the use of two
geometries: complete graph geometry to locate the global fitness minimizer, and
graph geometry to replace the species in the neighborhood of the minimizer. We
present a variant in which only the graph geometry is used. This allows to
obtain the stationary distribution through random walk dynamics. We use this to
show that for constant-degree graphs, the stationary fitness distribution
converges to an IID law as the number of vertices tends to infinity. We also
discuss exponential ergodicity through coupling, and avalanches for the model.


title: Scaling of tripartite entanglement at impurity quantum phase transitions

abstract:
  The emergence of a diverging length scale in many-body systems at a quantum
phase transition implies that total entanglement has to reach its maximum
there. In order to fully characterize this, one has to consider multipartite
entanglement as, for instance, bipartite entanglement between individual
particles fails to signal this effect. However, quantification of multipartite
entanglement is very hard and detecting it may not be possible due to the lack
of accessibility to all individual particles. For these reasons it will be more
sensible to partition the system into relevant subsystems, each containing few
to many spins, and study entanglement between those constituents as a
coarse-grain picture of multipartite entanglement between individual particles.
In impurity systems, famously exemplified by two-impurity and two-channel Kondo
models, it is natural to divide the system into three parts, namely, impurities
and the left and right bulks. By exploiting two tripartite entanglement
measures, based on negativity, we show that at impurity quantum phase
transitions the tripartite entanglement diverges and shows scaling behavior.
While the critical exponents are different for each tripartite entanglement
measure they both provide very similar critical exponents for the two-impurity
and the two-channel Kondo models suggesting that they belong to the same
universality class.


title: Manifest Covariant Hamiltonian Theory of General Relativity

abstract:
  The problem of formulating a manifest covariant Hamiltonian theory of General
Relativity in the presence of source fields is addressed, by extending the
so-called "DeDonder-Weyl" formalism to the treatment of classical fields in
curved space-time. The theory is based on a synchronous variational principle
for the Einstein equation, formulated in terms of superabundant variables. The
technique permits one to determine the continuum covariant Hamiltonian
structure associated with the Einstein equation. The corresponding continuum
Poisson bracket representation is also determined. The theory relies on
first-principles, in the sense that the conclusions are reached in the
framework of a non-perturbative covariant approach, which allows one to
preserve both the 4-scalar nature of Lagrangian and Hamiltonian densities as
well as the gauge invariance property of the theory.


title:
The Close AGN Reference Survey (CARS) - Mrk 1018 returns to the shadows
  after 30 years as a Seyfert 1

abstract:
  We report the discovery that the known `changing look' AGN Mrk 1018 has
changed spectral type for a second time. New VLT-MUSE data taken in 2015 as
part of the Close AGN Reference Survey (CARS) shows that the AGN has returned
to its original Seyfert 1.9 classification. The CARS sample is selected to
contain only bright type 1 AGN, but Mrk 1018's broad emission lines and
continuum, typical of type 1 AGN, have almost entirely disappeared. We use
spectral fitting of the MUSE spectrum and previously available spectra to
determine the drop in broad line flux and the Balmer decrement. We find that
the broad line flux has decreased by a factor of 4.75+/- 0.5 in H{\alpha} since
an SDSS spectrum was taken in 2000. The Balmer decrement has not changed
significantly implying no enhanced reddening with time, but the remaining broad
lines are more asymmetric than those present in the type 1 phase. We posit that
the change is due to an intrinsic drop in flux from the accretion disk rather
than variable extinction or a tidal disruption event.


title:
Ornstein-Uhlenbeck approximation of one-step processes: a differential
  equation approach

abstract:
  The steady state of the Fokker-Planck equation corresponding to a density
dependent one-step process is approximated by a suitable normal distribution.
Starting from the master equations of the process, written in terms of the time
dependent probabilities, $p_k(t)$ of the states $k=0,1,\ldots , N$, their
continuous (in space) version, the Fokker-Planck equation is formulated. This
PDE approximation enables us to create analytic approximation formulas for the
steady state distribution. These formulas are derived based on heuristic
reasoning and then their accuracy is proved to be of order $1/N^{\beta}$ with
some power $\beta <1$.


title:
The Close AGN Reference Survey (CARS) - What is causing Mrk1018's return
  to the shadows after 30 years?

abstract:
  We recently discovered that the active galactic nucleus (AGN) of Mrk 1018 has
changed optical type again after 30 years as a type 1 AGN. Here we combine
Chandra, NuStar, Swift, Hubble Space Telescope and ground-based observations to
explore the cause of this change. The 2-10keV flux declines by a factor of ~8
between 2010 and 2016. We show with our X-ray observation that this is not
caused by varying neutral hydrogen absorption along the line-of-sight up to the
Compton-thick level. The optical-UV spectral energy distributions are well fit
with a standard geometrically thin optically thick accretion disc model that
seems to obey the expected $L\sim T^4$ relation. It confirms that a decline in
accretion disc luminosity is the primary origin for the type change. We detect
a new narrow-line absorber in Lya blue-shifted by ~700km/s with respect to the
systemic velocity of the galaxy. This new Lya absorber could be evidence for
the onset of an outflow or a companion black hole with associated gas that
could be related to the accretion rate change. However, the low column density
of the absorber means that it is not the direct cause for Mrk 1018's
changing-look nature.


title:
Hamiltonian approach to GR - Part 1: covariant theory of classical
  gravity

abstract:
  A challenging issue in General Relativity concerns the determination of the
manifestly-covariant continuum Hamiltonian structure underlying the Einstein
field equations and the related formulation of the corresponding covariant
Hamilton-Jacobi theory. The task is achieved by adopting a synchronous
variational principle requiring distinction between the prescribed
deterministic metric tensor $\widehat{g}(r)\equiv \left\{ \widehat{g}_{\mu \nu
}(r)\right\} $ solution of the Einstein field equations which determines the
geometry of the background space-time and suitable variational fields $x\equiv
\left\{ g,\pi \right\} $ obeying an appropriate set of continuum Hamilton
equations, referred to here as GR-Hamilton equations$.$ It is shown that a
prerequisite for reaching such a goal is that of casting the same equations in
evolutionary form by means of a Lagrangian parametrization for a
suitably-reduced canonical state. As a result, the corresponding
Hamilton-Jacobi theory is established in manifestly-covariant form. Physical
implications of the theory are discussed. These include the investigation of
the structural stability of the GR-Hamilton equations with respect to vacuum
solutions of the Einstein equations, assuming that wave-like perturbations are
governed by the canonical evolution equations.


title: Connecting the quantum and classical worlds

abstract:
  By considering (non-relativistic) quantum mechanics as it is done in practice
in particular in condensed-matter physics, it is argued that a deterministic,
unitary time evolution within a chosen Hilbert space always has a limited
scope, leaving a lot of room for embedding the quantum-classical transition
into our current theories without recurring to difficult-to-accept
interpretations of quantum mechanics. Nonunitary projections to initial and
final states, the breaking of time-reversal symmetry, a change of Hilbert
space, and the introduction of classical concepts such as external potentials
or localized atomic nuclei are widespread in quantum mechanical calculations.
Furthermore, quantum systems require classical environments that enable the
symmetry breaking that is necessary for creating the atomic configurations of
molecules and crystals. This paper argues that such classical environments are
provided by finite-temperature macroscopic systems in which the range of
quantum correlations and entanglement is limited. This leads to classical
behavior on larger scales, and to collapse-like events in all dynamical
processes that become coupled to the thermalized degrees of freedom.


title: Hamiltonian approach to GR - Part 2: covariant theory of quantum gravity

abstract:
  A non-perturbative quantum field theory of General Relativity is presented
which leads to a new realization of the theory of Covariant Quantum-Gravity
(CQG-theory). The treatment is founded on the recently-identified Hamiltonian
structure associated with the classical space-time, i.e., the corresponding
manifestly-covariant Hamilton equations and the related Hamilton-Jacobi theory.
The quantum Hamiltonian operator and the CQG-wave equation for the
corresponding CQG-state and wave-function are realized in $% 4-$scalar form.
The new quantum wave equation is shown to be equivalent to a set of quantum
hydrodynamic equations which warrant the consistency with the classical GR
Hamilton-Jacobi equation in the semiclassical limit. A perturbative
approximation scheme is developed, which permits the adoption of the harmonic
oscillator approximation for the treatment of the Hamiltonian potential. As an
application of the theory, the stationary vacuum CQG-wave equation is studied,
yielding a stationary equation for the CQG-state in terms of the $4-$scalar
invariant-energy eigenvalue associated with the corresponding approximate
quantum Hamiltonian operator. The conditions for the existence of a discrete
invariant-energy spectrum are pointed out. This yields a possible estimate for
the graviton mass together with a new interpretation about the quantum origin
of the cosmological constant.


title: Extended Harmonic Map Equations and the Chaotic Soliton Solutions

abstract:
  In this paper, the theory of harmonic maps is extended. The soliton or
traveling wave solutions of Euler's equations of the extended harmonic maps are
studied. In certain cases, the chaotic behaviors of these partial equations can
be found for the particular case of the metrics and the potential functions of
the extended harmonic equations.


title: Soft-Collinear Supersymmetry

abstract:
  Soft-Collinear Effective Theory (SCET) is a framework for modeling the
infrared structure of theories whose long distance behavior is dominated by
soft and collinear divergences. This paper demonstrates that SCET can be made
compatible with supersymmetry (SUSY). Explicitly, the effective Lagrangian for
$\mathcal{N} = 1$ SUSY Yang-Mills is constructed and shown to be a complete
description for the infrared of this model. For contrast, we also construct the
effective Lagrangian for chiral SUSY theories with Yukawa couplings,
specifically the single flavor Wess-Zumino model. Only a subset of the infrared
divergences are reproduced by the Lagrangian -- to account for the complete low
energy description requires the inclusion of local operators. SCET is
formulated by expanding fields along a light-like direction and then
subsequently integrating out degrees-of-freedom that are away from the
light-cone. Defining the theory with respect to a specific frame obfuscates
Lorentz invariance -- given that SUSY is a space-time symmetry, this presents a
possible obstruction. The cleanest language with which to expose the congruence
between SUSY and SCET requires exploring two novel formalisms: collinear
fermions as two-component Weyl spinors, and SCET in light-cone gauge. By
expressing SUSY Yang-Mills in "collinear superspace", a slice of superspace
derived by integrating out half the fermionic coordinates, the light-cone gauge
SUSY SCET theory can be written in terms of superfields. As a byproduct,
bootstrapping up to the full theory yields the first algorithmic approach for
determining the SUSY Yang-Mills on-shell superspace action. This work paves the
way toward discovering the effective theory for the collinear limit of
$\mathcal{N} = 4$ SUSY Yang-Mills.


title: Note on the Bondal-Orlov Functors for Toric DM Stacks

abstract:
  We calculate explicit formulas for the general equivariant Bondal-Orlov
functors on the localized K-theory groups for a crepant birational
transformation of toric DM stacks. We recall some facts that the Bondal-Orlov
functors give equivalences on the bounded derived categories. Applying twice of
these functors we get the Seidel-Thomas spherical twists for the derived
category.


title: One-loop gravity divergences in D>4 cannot all be removed

abstract:
  Unlike the one-loop QG divergences in D=4, which can all be transformed away,
those in arbitrary higher (even) dimension cannot.


title: $L^p$ Expander Graphs

abstract:
  We discuss how graph expansion is related to the behavior of
$L^{p}$-functions on the covering tree. We show that the non-trivial
eigenvalues of the adjacency operator on aa $(q+1)$-regular graph are bounded
by $q^{1/p}+q^{(p-1)/p}$ - the $L^{p}$-norm of the operator on the covering
tree - if and only if properly averaged lifts of functions from the graph to
the tree lie in $L^{p+\epsilon}$ for every $\epsilon>0$. We generalize the
result to operators on edges and to bipartite graphs.
  The work is based on a combinatorial interpretation of
representation-theoretic ideas.


title:
A Panchromatic View of Relativistic Jets in Narrow-Line Seyfert 1
  Galaxies

abstract:
  The discovery by the Large Area Telescope on board Fermi of variable
gamma-ray emission from radio-loud narrow-line Seyfert 1 (NLSy1) galaxies
revealed the presence of a possible third class of Active Galactic Nuclei (AGN)
with relativistic jets in addition to blazars and radio galaxies. Considering
that NLSy1 are usually hosted in spiral galaxies, this finding poses intriguing
questions about the nature of these objects and the formation of relativistic
jets. We report on a systematic investigation of the gamma-ray properties of a
sample of radio-loud NLSy1, including the detection of new objects, using 7
years of Fermi-LAT data with the new Pass 8 event-level analysis. In addition
we discuss the radio-to-very-high-energy properties of the gamma-ray emitting
NLSy1, their host galaxy, and black hole mass in the context of the blazar
scenario and the unification of relativistic jets at different scales.


title: Pulse reflection in a random waveguide with a turning point

abstract:
  We present an analysis of wave propagation and reflection in an acoustic
waveguide with random sound soft boundary and a turning point. The waveguide
has slowly bending axis and variable cross section. The variation consists of a
slow and monotone change of the width of the waveguide and small and rapid
fluctuations of the boundary, on the scale of the wavelength. These
fluctuations are modeled as random. The turning point is many wavelengths away
from the source, which emits a pulse that propagates toward the turning point,
where it is reflected. To focus attention on this reflection, we assume that
the waveguide supports a single propagating mode from the source to the turning
point, beyond which all the waves are evanescent. We consider a scaling regime
where scattering at the random boundary has a significant effect on the
reflected pulse. In this regime scattering from the random boundary away from
the turning point is negligible, while scattering from the random boundary
around the turning point results in a strong, deterministic pulse deformation.
The reflected pulse shape is not the same as the emitted one. It is damped, due
to scattering at the boundary, and is deformed by dispersion in the waveguide.
The reflected pulse also carries a random phase.


title: Bayesian Reinforcement Learning: A Survey

abstract:
  Bayesian methods for machine learning have been widely investigated, yielding
principled methods for incorporating prior information into inference
algorithms. In this survey, we provide an in-depth review of the role of
Bayesian methods for the reinforcement learning (RL) paradigm. The major
incentives for incorporating Bayesian reasoning in RL are: 1) it provides an
elegant approach to action-selection (exploration/exploitation) as a function
of the uncertainty in learning; and 2) it provides a machinery to incorporate
prior knowledge into the algorithms. We first discuss models and methods for
Bayesian inference in the simple single-step Bandit model. We then review the
extensive recent literature on Bayesian methods for model-based RL, where prior
information can be expressed on the parameters of the Markov model. We also
present Bayesian methods for model-free RL, where priors are expressed over the
value function or policy class. The objective of the paper is to provide a
comprehensive survey on Bayesian RL algorithms and their theoretical and
empirical properties.


title:
Robust recovery-type a posteriori error estimators for streamline
  upwind/Petrov Galerkin discretizations for singularly perturbed problems

abstract:
  In this paper, we investigate adaptive streamline upwind/Petrov Galerkin
(SUPG) methods for singularly perturbed convection-diffusion-reaction equations
in a new dual norm presented in [Du and Zhang, J. Sci. Comput. (2015)]. The
flux is recovered by either local averaging in conforming $H({\rm div})$ spaces
or weighted global $L^2$ projection onto conforming $H({\rm div})$ spaces. We
further introduce a recovery stabilization procedure, and develop completely
robust a posteriori error estimators with respect to the singular perturbation
parameter $\varepsilon$. Numerical experiments are reported to support the
theoretical results and to show that the estimated errors depend on the degrees
of freedom uniformly in $\varepsilon$.


title:
Local approximation of arbitrary functions by solutions of nonlocal
  equations

abstract:
  We show that any function can be locally approximated by solutions of
prescribed linear equations of nonlocal type. In particular, we show that every
function is locally $s$-caloric, up to a small error. The case of non-elliptic
and non-parabolic operators is taken into account as well.


title:
Unrestricted State Complexity of Binary Operations on Regular and Ideal
  Languages

abstract:
  We study the state complexity of binary operations on regular languages over
different alphabets. It is known that if $L'_m$ and $L_n$ are languages of
state complexities $m$ and $n$, respectively, and restricted to the same
alphabet, the state complexity of any binary boolean operation on $L'_m$ and
$L_n$ is $mn$, and that of product (concatenation) is $m 2^n - 2^{n-1}$. In
contrast to this, we show that if $L'_m$ and $L_n$ are over different
alphabets, the state complexity of union and symmetric difference is
$(m+1)(n+1)$, that of difference is $mn+m$, that of intersection is $mn$, and
that of product is $m2^n+2^{n-1}$. We also study unrestricted complexity of
binary operations in the classes of regular right, left, and two-sided ideals,
and derive tight upper bounds. The bounds for product of the unrestricted cases
(with the bounds for the restricted cases in parentheses) are as follows: right
ideals $m+2^{n-2}+2^{n-1}$ ($m+2^{n-2}$); left ideals $mn+m+n$ ($m+n-1$);
two-sided ideals $m+2n$ ($m+n-1$). The state complexities of boolean operations
on all three types of ideals are the same as those of arbitrary regular
languages, whereas that is not the case if the alphabets of the arguments are
the same. Finally, we update the known results about most complex regular,
right-ideal, left-ideal, and two-sided-ideal languages to include the
unrestricted cases.


title: $\downarrow$-posets

abstract:
  We investigate a certain class of posets arising from semilattice actions.
Let $S$ be a semilattice with identity. Let $S$ act on a set $C$. For $c,d\in
C$ put $c\leq d$ iff there is some $s\in S$ with $ds=c$. Then $(C,\leq)$ is a
poset. Let's call the posets that arise in this way $\downarrow$-posets. We
give a reasonable second order characterization of $\downarrow$-posets and show
that there is no first order characterization.


title: Long-time behavior for crystal dislocation dynamics

abstract:
  We describe the asymptotic states for the solutions of a nonlocal equation of
evolutionary type, which have the physical meaning of the atom dislocation
function in a periodic crystal.
  More precisely, we can describe accurately the "smoothing effect" on the
dislocation function occurring slightly after a "particle collision" (roughly
speaking, two opposite transitions layers average out) and, in this way, we can
trap the atom dislocation function between a superposition of transition layers
which, as time flows, approaches either a constant function or a single
heteroclinic (depending on the algebraic properties of the orientations of the
initial transition layers).
  The results are endowed of explicit and quantitative estimates and, as a
byproduct, we show that the ODE systems of particles that governs the evolution
of the transition layers does not admit stationary solutions (i.e., roughly
speaking, transition layers always move).


title: Acoustic quasi-lossless transmission in arbitrary pathway of network

abstract:
  Acoustic metamaterials have exhibited extraordinary possibilities to
manipulate the propagation of the sound wave. Up to now, it is still a
challenge to control the propagation of the sound wave in an arbitrary pathway
of a network. Here, we design a symmetry breaking cross-shape metamaterial
comprised of Helmholtz resonant cells and a square column. The square column is
eccentrically arranged. The sound wave can quasi-lossless transmit through
channels along the eccentric direction with compressed spaces, which breaks
through the general transmission phenomenon. This exotic propagation
characteristic is verified by the band structure and the mode of the
metamaterial. Two acoustic networks, including a 2x2 network and an 8x8
network, show that the sound wave can quasi-lossless propagate along various
arbitrary pathways, such as the Great Wall shape, the stair step shape and the
serpentine shape, by reconfiguring eccentric directions. This ability opens up
a new venue to route the sound wave and exhibits promising applications, from
the acoustic communication to the energy transmission.


title: Stochastic evolution in populations of ideas

abstract:
  It is known that learning of players who interact in a repeated game can be
interpreted as an evolutionary process in a population of ideas. These
analogies have so far mostly been established in deterministic models, and
memory loss in learning has been seen to act similarly to mutation in
evolution. We here propose a representation of reinforcement learning as a
stochastic process in finite "populations of ideas". The resulting birth-death
dynamics has absorbing states and allows for the extinction or fixation of
ideas, marking a key difference to mutation-selection processes in finite
populations. We characterize the outcome of evolution in populations of ideas
for several classes of symmetric and asymmetric games.


title:
SPIRITS 15c and SPIRITS 14buu: Two Obscured Supernovae in the Nearby
  Star-Forming Galaxy IC 2163

abstract:
  SPIRITS---SPitzer InfraRed Intensive Transients Survey---is an ongoing survey
of nearby galaxies searching for infrared (IR) transients with Spitzer/IRAC. We
present the discovery and follow-up observations of one of our most luminous
($M_{[4.5]} = -17.1\pm0.4$ mag, Vega) and red ($[3.6] - [4.5] = 3.0 \pm 0.2$
mag) transients, SPIRITS 15c. The transient was detected in a dusty spiral arm
of IC 2163 ($D\approx35.5$ Mpc). Pre-discovery ground-based imaging revealed an
associated, shorter-duration transient in the optical and near-IR (NIR). NIR
spectroscopy showed a broad ($\approx 8400$ km s$^{-1}$), double-peaked
emission line of He I at $1.083 \mu$m, indicating an explosive origin. The NIR
spectrum of SPIRITS 15c is similar to that of the Type IIb SN 2011dh at a phase
of $\approx 200$ days. Assuming $A_V = 2.2$ mag of extinction in SPIRITS 15c
provides a good match between their optical light curves. The IR light curves
and the extreme $[3.6]-[4.5]$ color cannot be explained using only a standard
extinction law. Another luminous ($M_{4.5} = -16.1\pm0.4$ mag) event, SPIRITS
14buu, was serendipitously discovered in the same galaxy. The source displays
an optical plateau lasting $\gtrsim 80$ days, and we suggest a scenario similar
to the low-luminosity Type IIP SN 2005cs obscured by $A_V \approx 1.5$ mag.
Other classes of IR-luminous transients can likely be ruled out in both cases.
If both events are indeed SNe, this may suggest $\gtrsim 18\%$ of nearby
core-collapse SNe are missed by currently operating optical surveys.


title:
Temperature Dependent Luminescent Decay Properties of CdTe Quantum Dot
  Monolayers: Impact of Concentration on Carrier Trapping

abstract:
  We have investigated the temperature dependence of the photoluminescence
spectra and average photoluminescence decay rate of CdTe quantum dot monolayers
of different sizes as a function of concentration in the range 77 K to 296 K.
It is shown that a simple three level analytic model involving bright and dark
exciton states can only describe the lower temperature data but is unable to
satisfactorily fit the data over the full temperature range. An extended model
which includes external trap states is necessary to fit the data above
approximately 150 K. Parameters for the model are obtained using both temporal
and spectral data. The model indicates that the efficiency of interaction with
trap states increases as the QD monolayer concentration increases, which is
likely due to an increase in the density of available traps.


title: On the Magnetic Interaction of Dirac Particles

abstract:
  It is shown that the magnetic force between two classical point charges, each
undergoing relativistic circulatory motion of small radius compared to the
separation between their centers of circulation, and assuming a time-symmetric
electromagnetic interaction, is modulated by a factor that behaves similarly to
the Schr\"odinger wavefunction. The modulation solves an equation formally
identical to the time-dependent free-particle Schr\"odinger equation, apart
from a factor of two on the partial time derivative term. Separating variables
and considering motion in a time-independent potential obtains that the
modulation also satisfies an equation formally similar to the time-independent
Schro\"dinger equation. Using a formula for relativistic rest energy advanced
by Osiak, the time-independent Schr\"odinger equation is solved exactly by the
resulting modulation function. A simple interpretation for the quantum
mechanical wavefunction is proposed.


title:
Direct data-driven control of constrained linear parameter-varying
  systems: A hierarchical approach

abstract:
  In many nonlinear control problems, the plant can be accurately described by
a linear model whose operating point depends on some measurable variables,
called scheduling signals. When such a linear parameter-varying (LPV) model of
the open-loop plant needs to be derived from a set of data, several issues
arise in terms of parameterization, estimation, and validation of the model
before designing the controller. Moreover, the way modeling errors affect the
closed-loop performance is still largely unknown in the LPV context. In this
paper, a direct data-driven control method is proposed to design LPV
controllers directly from data without deriving a model of the plant. The main
idea of the approach is to use a hierarchical control architecture, where the
inner controller is designed to match a simple and a-priori specified
closed-loop behavior. Then, an outer model predictive controller is synthesized
to handle input/output constraints and to enhance the performance of the inner
loop. The effectiveness of the approach is illustrated by means of a simulation
and an experimental example. Practical implementation issues are also
discussed.


title: New Physics from rare decays of charm

abstract:
  Abundance of charm data in the current and future low energy flavor
experiments makes it possible to study rare decays of D-mesons with ever
increased precision. I discuss theoretical implications of derived constraints
on New Physics models from these transitions. I argue that those constraints
could be competitive with results of direct searches for New Physics particles
(including Dark Matter) at the Large Hadron Collider.


title:
On the Computational Complexity of Minimal Cumulative Cost Graph
  Pebbling

abstract:
  We consider the computational complexity of finding a legal black pebbling of
a DAG $G=(V,E)$ with minimum cumulative cost. A black pebbling is a sequence
$P_0,\ldots, P_t \subseteq V$ of sets of nodes which must satisfy the following
properties: $P_0 = \emptyset$ (we start off with no pebbles on $G$),
$\mathsf{sinks}(G) \subseteq \bigcup_{j \leq t} P_j$ (every sink node was
pebbled at some point) and $\mathsf{parents}\big(P_{i+1}\backslash P_i\big)
\subseteq P_i$ (we can only place a new pebble on a node $v$ if all of $v$'s
parents had a pebble during the last round). The cumulative cost of a pebbling
$P_0,P_1,\ldots, P_t \subseteq V$ is $\mathsf{cc}(P) = | P_1| + \ldots + |
P_t|$. The cumulative pebbling cost is an especially important security metric
for data-independent memory hard functions, an important primitive for password
hashing. Thus, an efficient (approximation) algorithm would be an invaluable
tool for the cryptanalysis of password hash functions as it would provide an
automated tool to establish tight bounds on the amortized space-time cost of
computing the function. We show that such a tool is unlikely to exist. In
particular, we prove the following results. (1) It is
$\texttt{NP}\mbox{-}\texttt{Hard}$ to find a pebbling minimizing cumulative
cost. (2) The natural linear program relaxation for the problem has integrality
gap $\tilde{O}(n)$, where $n$ is the number of nodes in $G$. We conjecture that
the problem is hard to approximate. (3) We show that a related problem, find
the minimum size subset $S\subseteq V$ such that $\textsf{depth}(G-S) \leq d$,
is also $\texttt{NP}\mbox{-}\texttt{Hard}$. In fact, under the unique games
conjecture there is no $(2-\epsilon)$-approximation algorithm.


title: An Introduction to Graphene Plasmonics

abstract:
  This book is meant as an introduction to graphene plasmonics and aims at the
advanced undergraduate and graduate students entering the field of plasmonics
in graphene. In it different theoretical methods are introduced, starting with
an elementary description of graphene plasmonics and evolving towards more
advanced topics. This book is essentially self-contained and brings together a
number of different topics about the field that are scattered in the vast
literature. The text is composed of eleven chapters and of a set of detailed
appendices. It can be read in two different ways: Reading only the chapters to
get acquainted with the field of plasmonics in graphene or reading the chapters
and studying the appendices to get a working knowledge of the topic. The study
of the material in this book will bring the students to the forefront of the
research in this field.


title:
Search for ultrarelativistic magnetic monopoles with the Pierre Auger
  Observatory

abstract:
  We present a search for ultra-relativistic magnetic monopoles with the Pierre
Auger Observatory. Such particles, possibly a relic of phase transitions in the
early universe, would deposit a large amount of energy along their path through
the atmosphere, comparable to that of ultrahigh-energy cosmic rays (UHECRs).
The air shower profile of a magnetic monopole can be effectively distinguished
by the fluorescence detector from that of standard UHECRs. No candidate was
found in the data collected between 2004 and 2012, with an expected background
of less than 0.1 event from UHECRs. The corresponding 90% confidence level
(C.L.) upper limits on the flux of ultra-relativistic magnetic monopoles range
from $10^{-19}$ (cm$^{2}$ sr s)$^{-1}$ for a Lorentz factor $\gamma=10^9$ to
$2.5 \times10^{-21}$ (cm$^{2}$ sr s)$^{-1}$ for $\gamma=10^{12}$. These results
- the first obtained with a UHECR detector - improve previously published
limits by up to an order of magnitude.


title: Fragmentation Kinematics in Comet 332P/Ikeya-Murakami

abstract:
  We present initial time-resolved observations of the split comet
332P/Ikeya-Murakami taken using the Hubble Space Telescope. Our images reveal a
dust-bathed cluster of fragments receding from their parent nucleus at
projected speeds in the range 0.06 to 3.5 m s$^{-1}$ from which we estimate
ejection times from October to December 2015. The number of fragments with
effective radii $\gtrsim$20 m follows a differential power law with index
$\gamma$ = -3.6$\pm$0.6, while smaller fragments are less abundant than
expected from an extrapolation of this power-law. We argue that, in addition to
losses due to observational selection, torques from anisotropic outgassing are
capable of destroying the small fragments by driving them quickly to rotational
instability. Specifically, the spin-up times of fragments $\lesssim$20 m in
radius are shorter than the time elapsed since ejection from the parent
nucleus. The effective radius of the parent nucleus is $r_e \le$ 275 m
(geometric albedo 0.04 assumed). This is about seven times smaller than
previous estimates and results in a nucleus mass at least 300 times smaller
than previously thought. The mass in solid pieces, $2\times10^9$ kg, is about
4% of the mass of the parent nucleus. As a result of its small size, the parent
nucleus also has a short spin-up time. Brightness variations in time-resolved
nucleus photometry are consistent with rotational instability playing a role in
the release of fragments.


title:
A Large Contextual Dataset for Classification, Detection and Counting of
  Cars with Deep Learning

abstract:
  We have created a large diverse set of cars from overhead images, which are
useful for training a deep learner to binary classify, detect and count them.
The dataset and all related material will be made publically available. The set
contains contextual matter to aid in identification of difficult targets. We
demonstrate classification and detection on this dataset using a neural network
we call ResCeption. This network combines residual learning with
Inception-style layers and is used to count cars in one look. This is a new way
to count objects rather than by localization or density estimation. It is
fairly accurate, fast and easy to implement. Additionally, the counting method
is not car or scene specific. It would be easy to train this method to count
other kinds of objects and counting over new scenes requires no extra set up or
assumptions about object locations.


title: Calabi-Yau compactification of type II string theories

abstract:
  Superstring theories are the most promising theories for unified description
of all fundamental interactions including gravity. However, these theories are
formulated consistently only in 10 spacetime dimensions. Therefore, to connect
to the observable world, it is required to compactify 6 out of those 10
dimensions in a suitable fashion.
  In this thesis, we mainly consider compactifications of type II string
theories on Calabi-Yau threefolds. As a consequence, the resulting four
dimensional theories preserve $\mathcal{N}=2$ supersymmetry. In these cases the
metrics on the moduli spaces of the matter multiplets, vector and
hypermultiplets, completely determine the low energy theories. Whereas the
former are very well understood by now, the complete description of
hypermultiplets is more complicated. In fact, hypermultiplets receive both
perturbative and non-perturbative corrections. The thesis mainly pertains to
the understanding of the non-perturbative corrections. Our findings for the
hypermultiplets rely on the so called twistorial construction. We discuss this
technique in details and use it throughout the course of this thesis. In
particular, armed with this, and exploiting various symmetries, especially
S-duality and mirror symmetry, we discuss the procedure to derive the D-brane
and NS5-brane instanton corrections to the hypermultiplet moduli space.


title:
Public repository with Monte Carlo simulations for high-energy particle
  collision experiments

abstract:
  Planning high-energy collision experiments for the next few decades requires
extensive Monte Carlo simulations in order to accomplish physics goals of these
experiments. Such simulations are essential for understanding fundamental
physics processes, as well as for setting up the detector parameters that help
establish R&D projects required over the next few decades. This paper describes
a public repository with Monte Carlo event samples before and after
detector-response simulation. The goal of this repository is to facilitate the
accomplishment of many goals in planning a next generation of particle
experiments.


title: Extraction of the proton charge radius from experiments

abstract:
  Static properties of hadrons such as their radii and other moments of the
electric and magnetic distributions can only be extracted using theoretical
methods and not directly measured from experiments. As a result, discrepancies
between the extracted values from different precision measurements can exist.
The proton charge radius, $r_p$, which is either extracted from electron proton
elastic scattering data or from hydrogen atom spectroscopy seems to be no
exception. The value $r_p = 0.84087(39)$ fm extracted from muonic hydrogen
spectroscopy is about 4% smaller than that obtained from electron proton
scattering or standard hydrogen spectroscopy. The resolution of this so called
proton radius puzzle has been attempted in many different ways over the past
six years. The present article reviews these attempts with a focus on the
methods of extracting the radius.


title: The Final Fates of Accreting Supermassive Stars

abstract:
  The formation of supermassive stars (SMSs) via rapid mass accretion and their
direct collapse into black holes (BHs) is a promising pathway for sowing seeds
of supermassive BHs in the early universe. We calculate the evolution of
rapidly accreting SMSs by solving the stellar structure equations including
nuclear burning as well as general relativistic (GR) effects up to the onset of
the collapse. We find that such SMSs have less concentrated structure than
fully-convective counterpart, which is often postulated for non-accreting ones.
This effect stabilizes the stars against GR instability even above the
classical upper mass limit $\gtrsim 10^5~M_\odot$ derived for the
fully-convective stars. The accreting SMS begins to collapse at the higher mass
with the higher accretion rate. The collapse occurs when the nuclear fuel is
exhausted only for cases with $\dot M \lesssim 0.1~M_\odot~{\rm yr}^{-1}$. With
$\dot{M} \simeq 0.3 - 1~M_\odot~{\rm yr}^{-1}$, the star becomes GR-unstable
during the helium-burning stage at $M \simeq 2 - 3.5~\times 10^5~M_\odot$. In
an extreme case with $10~M_\odot~{\rm yr}^{-1}$, the star does not collapse
until the mass reaches $\simeq 8.0\times 10^5~M_\odot$, where it is still in
the hydrogen-burning stage. We expect that BHs with roughly the same mass will
be left behind after the collapse in all the cases.


title: On the asymptotic Fermat's Last Theorem over number fields

abstract:
  Assuming two deep but standard conjectures from the Langlands Programme, we
prove that the asymptotic Fermat's Last Theorem holds for imaginary quadratic
fields Q(\sqrt{-d}) with -d=2, 3 mod 4. For a general number field K, again
assuming standard conjectures, we give a criterion based on the solutions to a
certain S-unit equation, which if satisfied implies the asymptotic Fermat's
Last Theorem.


title:
Anisotropic flow measurements in Pb--Pb collisions at 5.02 TeV with
  ALICE

abstract:
  Anisotropic flow is a sensitive probe of the initial conditions and the
transport properties of the Quark Gluon Plasma (QGP) produced in heavy-ion
collisions. In these proceedings, we present the first results of elliptic
($v_2$), triangular ($v_3$) and quadrangular flow ($v_4$) of charged particles
in Pb--Pb collisions at $\sqrt{s_{_{\rm NN}}}=$ 5.02 TeV with the ALICE
detector. In addition, the comparison of experimental measurements to various
theoretical calculations will be discussed. This provides a unique opportunity
to test the validity of the hydrodynamic picture and discriminates between
various possibilities for the temperature dependence of shear viscosity to
entropy density ratio of the produced QGP.


title:
On completeness of coherent states in noncommutative spaces with
  generalised uncertainty principle

abstract:
  Coherent states are required to form a complete set of vectors in the Hilbert
space by providing the resolution of identity. We study the completeness of
coherent states for two different models in a noncommutative space associated
with the generalised uncertainty relation by finding the resolution of unity
with a positive definite weight function. The weight function, which is
sometimes known as the Borel measure, is obtained through explicit analytic
solutions of the Stieltjes and Hausdorff moment problem with the help of the
standard techniques of inverse Mellin transform.


title: Twisted self-duality for higher spin gauge fields and prepotentials

abstract:
  We show that the equations of motion for (free) integer higher spin gauge
fields can be formulated as twisted self-duality conditions on the higher spin
curvatures of the spin-$s$ field and its dual. We focus on the case of four
spacetime dimensions, but formulate our results in a manner applicable to
higher spacetime dimensions. The twisted self-duality conditions are redundant
and we exhibit a non-redundant subset of conditions, which have the remarkable
property to involve only first-order derivatives with respect to time. This
non-redundant subset equates the electric field of the spin-$s$ field (which we
define) to the magnetic field of its dual (which we also define), and vice
versa. The non-redundant subset of twisted self-duality conditions involve the
purely spatial components of the spin-$s$ field and its dual, and also the
components of the fields with one zero index. One can get rid of these gauge
components by taking the curl of the equations, which does not change their
physical content. In this form, the twisted self-duality conditions can be
derived from a variational principle that involves prepotentials, which are the
higher spin generalizations of the prepotentials previously found in the spins
2 and 3 cases. The prepotentials have again the intriguing feature of
possessing both higher spin diffeomorphism invariance and higher spin conformal
geometry. The tools introduced in an earlier paper for handling higher spin
conformal geometry turn out to be crucial for streamlining the analysis. In
four spacetime dimensions where the electric and magnetic fields are tensor
fields of the same type, the twisted self-duality conditions enjoy an $SO(2)$
electric-magnetic invariance. We explicitly show that this symmetry is an
"off-shell symmetry" (i.e., a symmetry of the action and not just of the
equations of motion). Remarks on the extension to higher dimensions are given.


title:
Do individual Spitzer young stellar object candidates enclose multiple
  UKIDSS sources?

abstract:
  We analyze near-infrared UKIDSS observations of a sample of 8325 objects
taken from a catalog of intrinsically red sources in the Galactic plane
selected in the Spitzer-GLIMPSE survey. Given the differences in angular
resolution (factor >2 better in UKIDSS), our aim is to investigate whether
there are multiple UKIDSS sources that might all contribute to the GLIMPSE
flux, or there is only one dominant UKIDSS counterpart. We then study possible
corrections to estimates of the SFR based on counts of GLIMPSE young stellar
objects (YSOs). This represents an exploratory work towards the construction of
a hierarchical YSO catalog. After performing PSF fitting photometry in the
UKIDSS data, we implemented a technique to automatically recognize the dominant
UKIDSS sources by evaluating their match with the spectral energy distribution
(SED) of the associated GLIMPSE red sources. This is a generic method which
could be robustly applied for matching SEDs across gaps at other wavelengths.
We found that most (87.0% +- 1.6%) of the candidate YSOs from the GLIMPSE red
source catalog have only one dominant UKIDSS counterpart which matches the
mid-infrared SED (fainter associated UKIDSS sources might still be present).
Though at first sight this could seem surprising, given that YSOs are typically
in clustered environments, we argue that within the mass range covered by the
GLIMPSE YSO candidates (intermediate to high masses), clustering with objects
with comparable mass is unlikely at the GLIMPSE resolution. Indeed, by
performing simple clustering experiments based on a population synthesis model
of Galactic YSOs, we found that although ~60% of the GLIMPSE YSO enclose at
least two UKIDSS sources, in general only one dominates the flux. No
significant corrections are needed for estimates of the SFR of the Milky Way
based on the assumption that the GLIMPSE YSOs are individual objects.
(Abridged)


title: Momentum distribution of N$^*$ in nuclei

abstract:
  Due to its dominance in the low energy eta-nucleon interaction, the S11
N$^*$(1535) resonance enters as an important ingredient in the analyses of
experiments aimed at finding evidence for the existence of eta-mesic nuclei.
The static properties of the resonance get modified inside the nucleus and its
momentum distribution is used in deciding these properties as well as the
kinematics in the analyses. Here we show that given the possibility for the
existence of an N$^*$-$^3$He quasibound state, the relative momentum
distribution of an N$^*$ and $^3$He inside such a $^4$He is narrower than that
of neutron-$^3$He in $^4$He. Results for the N$^*$-$^{24}$Mg system are also
presented. The present exploratory work could be useful in motivating searches
of exotic N$^*$-nucleus quasibound states as well as in performing analyses of
eta meson production data.


title:
Peer Encouragement Designs in Causal Inference with Partial Interference
  and Identification of Local Average Network Effects

abstract:
  In non-network settings, encouragement designs have been widely used to
analyze causal effects of a treatment, policy, or intervention on an outcome of
interest when randomizing the treatment was considered impractical or when
compliance to treatment cannot be perfectly enforced. Unfortunately, such
questions related to treatment compliance have received less attention in
network settings and the most well-studied experimental design in networks, the
two-stage randomization design, requires perfect compliance with treatment. The
paper proposes a new experimental design called peer encouragement design to
study network treatment effects when enforcing treatment randomization is not
feasible. The key idea in peer encouragement design is the idea of personalized
encouragement, which allows point-identification of familiar estimands in the
encouragement design literature. The paper also defines new causal estimands,
local average network effects, that can be identified under the new design and
analyzes the effect of non-compliance behavior in randomized experiments on
networks.


title: Early observations of the nearby type Ia supernova SN 2015F

abstract:
  We present photometry and time-series spectroscopy of the nearby type Ia
supernova (SN Ia) SN 2015F over $-16$ days to $+80$ days relative to maximum
light, obtained as part of the Public ESO Spectroscopic Survey of Transient
Objects (PESSTO). SN 2015F is a slightly sub-luminous SN Ia with a decline rate
of $\Delta m15(B)=1.35 \pm 0.03$ mag, placing it in the region between normal
and SN 1991bg-like events. Our densely-sampled photometric data place tight
constraints on the epoch of first light and form of the early-time light curve.
The spectra exhibit photospheric C II $\lambda 6580$ absorption until $-4$
days, and high-velocity Ca II is particularly strong at $<-10$ days at
expansion velocities of $\simeq$23000\kms. At early times, our spectral
modelling with syn++ shows strong evidence for iron-peak elements (Fe II, Cr
II, Ti II, and V II) expanding at velocities $>14000$ km s$^{-1}$, suggesting
mixing in the outermost layers of the SN ejecta. Although unusual in SN Ia
spectra, including V II in the modelling significantly improves the spectral
fits. Intriguingly, we detect an absorption feature at $\sim$6800 \AA\ that
persists until maximum light. Our favoured explanation for this line is
photospheric Al II, which has never been claimed before in SNe Ia, although
detached high-velocity C II material could also be responsible. In both cases
the absorbing material seems to be confined to a relatively narrow region in
velocity space. The nucleosynthesis of detectable amounts of Al II would argue
against a low-metallicity white dwarf progenitor. We also show that this 6800
\AA\ feature is weakly present in other normal SN Ia events, and common in the
SN 1991bg-like sub-class.


title:
Phenotyping using Structured Collective Matrix Factorization of
  Multi--source EHR Data

abstract:
  The increased availability of electronic health records (EHRs) have
spearheaded the initiative for precision medicine using data driven approaches.
Essential to this effort is the ability to identify patients with certain
medical conditions of interest from simple queries on EHRs, or EHR-based
phenotypes. Existing rule--based phenotyping approaches are extremely labor
intensive. Instead, dimensionality reduction and latent factor estimation
techniques from machine learning can be adapted for phenotype extraction with
no (or minimal) human supervision.
  We propose to identify an easily interpretable latent space shared across
various sources of EHR data as potential candidates for phenotypes. By
incorporating multiple EHR data sources (e.g., diagnosis, medications, and lab
reports) available in heterogeneous datatypes in a generalized
\textit{Collective Matrix Factorization (CMF)}, our methods can generate rich
phenotypes. Further, easy interpretability in phenotyping application requires
sparse representations of the candidate phenotypes, for example each phenotype
derived from patients' medication and diagnosis data should preferably be
represented by handful of diagnosis and medications, ($5$--$10$ active
components). We propose a constrained formulation of CMF for estimating sparse
phenotypes. We demonstrate the efficacy of our model through an extensive
empirical study on EHR data from Vanderbilt University Medical Center.


title:
Measurement of the Drift Velocity and Transverse Diffusion of Electrons
  in Liquid Xenon with the EXO-200 Detector

abstract:
  The EXO-200 Collaboration is searching for neutrinoless double beta decay
using a liquid xenon (LXe) time projection chamber. This measurement relies on
modeling the transport of charge deposits produced by interactions in the LXe
to allow discrimination between signal and background events. Here we present
measurements of the transverse diffusion constant and drift velocity of
electrons at drift fields between 20~V/cm and 615~V/cm using EXO-200 data. At
the operating field of 380~V/cm EXO-200 measures a drift velocity of
1.705$_{-0.010}^{+0.014}$~mm/$\mu$s and a transverse diffusion coefficient of
55$\pm$4~cm$^2$/s.


title: Sampling Generative Networks

abstract:
  We introduce several techniques for sampling and visualizing the latent
spaces of generative models. Replacing linear interpolation with spherical
linear interpolation prevents diverging from a model's prior distribution and
produces sharper samples. J-Diagrams and MINE grids are introduced as
visualizations of manifolds created by analogies and nearest neighbors. We
demonstrate two new techniques for deriving attribute vectors: bias-corrected
vectors with data replication and synthetic vectors with data augmentation.
Binary classification using attribute vectors is presented as a technique
supporting quantitative analysis of the latent space. Most techniques are
intended to be independent of model type and examples are shown on both
Variational Autoencoders and Generative Adversarial Networks.


title:
Anharmonic and Quantum Fluctuations in Molecular Crystals: A
  First-Principles Study of the Stability of Paracetamol

abstract:
  Molecular crystals often exist in multiple competing polymorphs, showing
significantly different physico-chemical properties. Computational crystal
structure prediction is key to interpret and guide the search for the most
stable or useful form: A real challenge due to the combinatorial search space,
and the complex interplay of subtle effects that work together to determine the
relative stability of different structures. Here we take a comprehensive
approach based on different flavors of thermodynamic integration in order to
estimate all contributions to the free energies of these systems with
density-functional theory, including the oft-neglected anharmonic contributions
and nuclear quantum effects. We take the two main stable forms of paracetamol
as a paradigmatic example. We find that anharmonic contributions, different
descriptions of van der Waals interactions, and nuclear quantum effects all
matter to quantitatively determine the stability of different phases. Our
analysis highlights the many challenges inherent in the development of a
quantitative and predictive framework to model molecular crystals. However, it
also indicates which of the components of the free energy can benefit from a
cancellation of errors that can redeem the predictive power of approximate
models, and suggests simple steps that could be taken to improve the
reliability of ab initio crystal structure prediction.


title:
The Type Ia Supernova Color-Magnitude Relation and Host Galaxy Dust: A
  Simple Hierarchical Bayesian Model

abstract:
  Conventional Type Ia supernova (SN Ia) cosmology analyses currently use a
simplistic linear regression of magnitude versus color and light curve shape,
which does not model intrinsic SN Ia variations and host galaxy dust as
physically distinct effects, resulting in low color-magnitude slopes. We
construct a probabilistic generative model for the dusty distribution of
extinguished absolute magnitudes and apparent colors as the convolution of a
intrinsic SN Ia color-magnitude distribution and a host galaxy dust
reddening-extinction distribution. If the intrinsic color-magnitude ($M_B$ vs.
$B-V$) slope $\beta_{int}$ differs from the host galaxy dust law $R_B$, this
convolution results in a specific curve of mean extinguished absolute magnitude
vs. apparent color. The derivative of this curve smoothly transitions from
$\beta_{int}$ in the blue tail to $R_B$ in the red tail of the apparent color
distribution. The conventional linear fit approximates this effective curve
near the average apparent color, resulting in an apparent slope $\beta_{app}$
between $\beta_{int}$ and $R_B$. We incorporate these effects into a
hierarchical Bayesian statistical model for SN Ia light curve measurements, and
analyze a dataset of SALT2 optical light curve fits of 248 nearby SN Ia at z <
0.10. The conventional linear fit obtains $\beta_{app} \approx 3$. Our model
finds a $\beta_{int} = 2.3 \pm 0.3$ and a distinct dust law of $R_B = 3.8 \pm
0.3$, consistent with the average for Milky Way dust, while correcting a
systematic distance bias of $\sim 0.10$ mag in the tails of the apparent color
distribution. Finally, we extend our model to examine the SN Ia luminosity-host
mass dependence in terms of intrinsic and dust components.


title: Sort Race

abstract:
  Sorting is one of the oldest computing problems and is still very important
in the age of big data. Various algorithms and implementation techniques have
been proposed. In this study, we focus on comparison based, internal sorting
algorithms. We created 12 data types of various sizes for experiments and
tested extensively various implementations in a single setting. Using some
effective techniques, we discovered that quicksort is adaptive to nearly sorted
inputs and is still the best overall sorting algorithm. We also identified
which techniques are effective in timsort, one of the most popular and
efficient sorting method based on natural mergesort, and created our version of
mergesort, which runs faster than timsort on nearly sorted instances. Our
implementations of quicksort and mergesort are different from other
implementations reported in all textbooks or research articles, faster than any
version of the C library qsort functions, not only for randomly generated data,
but also for various types of nearly sorted data. This experiment can help the
user to choose the best sorting algorithm for the hard sorting job at hand.
This work provides a platform for anyone to test their own sorting algorithm
against the best in the field.


title:
Graphical analysis of Current-Voltage Characteristics in Typical
  Memristive Interfaces

abstract:
  A graphical representation based on the isothermal current-voltage (IV)
measurements of typical memristive interfaces is presented. This is the
starting point to extract relevant microscopic information of the parameters
that control the electrical properties of a device based on a particular
metal-oxide interface. The convenience of the method is illustrated presenting
some examples were the IV characteristics were simulated in order to gain
insight on the influence of the fitting parameters.


title: Instability of Renormalization

abstract:
  In the theory of renormalization for classical dynamical systems, e.g.
unimodal maps and critical circle maps, topological conjugacy classes are
stable manifolds of renormalization. Physically more realistic systems on the
other hand may exhibit instability of renormalization within a topological
class. This instability gives rise to new phenomena and opens up directions of
inquiry that go beyond the classical theory. In phase space it leads to the
coexistence phenomenon, i.e. there are systems whose attractor has bounded
geometry but which are topologically conjugate to systems whose attractor has
degenerate geometry; in parameter space it causes dimensional discrepancy, i.e.
a topologically full family has too few dimensions to realize all possible
geometric behavior.


title: Polarimetric studies of magnetic turbulence with interferometer

abstract:
  We study statistical properties of synchrotron polarization emitted from
media with magnetohydrodynamic (MHD) turbulence. We use both synthetic and MHD
turbulence simulation data for our studies. We obtain the spatial spectrum and
its derivative with respect to wavelength of synchrotron polarization arising
from both synchrotron radiation and Faraday rotation fluctuations. In
particular, we investigate how the spectrum changes with frequency. We find
that our simulations agree with the theoretical predication in Lazarian \&
Pogosyan (2016). We conclude that the spectrum of synchrotron polarization and
it derivative can be very informative tools to get detailed information about
the statistical properties of MHD turbulence from radio observations of diffuse
synchrotron polarization. Especially, they are useful to recover the statistics
of turbulent magnetic field as well as turbulent density of electrons. We also
simulate interferometric observations that incorporate the effects of noise and
finite telescope beam size, and demonstrate how we recover statistics of
underlying MHD turbulence.


title:
Stability of transition waves and positive entire solutions of
  Fisher-KPP equations with time and space dependence

abstract:
  This paper is concerned with the stability of transition waves and strictly
positive entire solutions of random and nonlocal dispersal evolution equations
of Fisher-KPP type with general time and space dependence, including time and
space periodic or almost periodic dependence as special cases. We first show
the existence, uniqueness, and stability of strictly positive entire solutions
of such equations. Next, we show the stability of uniformly continuous
transition waves connecting the unique strictly positive entire solution and
the trivial solution zero and satisfying certain decay property at the end
close to the trivial solution zero (if it exists). The existence of transition
waves has been studied in [34, 39, 45, 46, 61] for random dispersal Fisher-KPP
equations with time and space periodic dependence, in [41, 42, 43, 51, 52, 53,
58, 63] for random dispersal Fisher-KPP equations with quite general time
and/or space dependence, and in [17, 48, 56] for nonlocal dispersal Fisher-KPP
equations with time and/or space periodic dependence. The stability result
established in this paper implies that the transition waves obtained in many of
the above mentioned papers are asymptotically stable. Up to the author's
knowledge, it is the first time that the stability of transition waves of
Fisher-KPP equations with both time and space dependence is studied.


title:
Comment on 'Unraveling Photoinduced Spin Dynamics in the Topological
  Insulator Bi2Se3'

abstract:
  Comment on a recent paper published in Physical Review Letters by M. C. Wang,
S. Qiao, Z. Jiang, S. N. Luo, and J. Qi [Phys. Rev. Lett. 116, 036601 (2016),
arXiv:1511.02994v2].


title: Eigenvalue location in cographs

abstract:
  We give an $O(n)$ time and space algorithm for constructing a diagonal matrix
congruent to A+xI, where A is the adjacency matrix of a cograph and $x\in
\mathbb{R}$. Applications include determining the number of eigenvalues of a
cograph's adjacency matrix that lie in any interval, obtaining a formula for
the inertia of a cograph, and exhibiting infinitely many pairs of equienergetic
cographs with integer energy.


title: Sterrett Procedure for the Generalized Group Testing Problem

abstract:
  Group testing is a useful method that has broad applications in medicine,
engineering, and even in airport security control. Consider a finite population
of $N$ items, where item $i$ has a probability $p_i$ to be defective. The goal
is to identify all items by means of group testing. This is the generalized
group testing problem. The optimum procedure, with respect to the expected
total number of tests, is unknown even in case when all $p_i$ are equal.
\cite{H1975} proved that an ordered partition (with respect to $p_i$) is the
optimal for the Dorfman procedure (procedure $D$), and obtained an optimum
solution (i.e., found an optimal partition) by dynamic programming. In this
paper, we investigate the Sterrett procedure (procedure $S$). We provide close
form expression for the expected total number of tests, which allows us to find
the optimum arrangement of the items in the particular group. We also show that
an ordered partition is not optimal for the procedure $S$ or even for a
slightly modified Dorfman procedure (procedure $D^{\prime}$). This discovery
implies that finding an optimal procedure $S$ appears to be a hard
computational problem. However, by using an optimal ordered partition for all
procedures, we show that procedure $D^{\prime}$ is uniformly better than
procedure $D$, and based on numerical comparisons, procedure $S$ is uniformly
and significantly better than procedures $D$ and $D^{\prime}$.


title:
Optical and Electrical Properties of Nanostructured Metallic Electrical
  Contacts

abstract:
  We study the optical and electrical properties of silver films with a graded
thickness obtained through metallic evaporation in vacuum on a tilted substrate
to evaluate their use as semitransparent electrical contacts. We measure their
ellipsometric coefficients, optical transmissions and electrical conductivity
for different widths, and we employ an efficient recursive method to calculate
their macroscopic dielectric function, their optical properties and their
microscopic electric fields. The topology of very thin films corresponds to
disconnected islands, while very wide films are simply connected. For
intermediate widths the film becomes semicontinuous, multiply connected, and
its microscopic electric field develops hotspots at optical resonances which
appear near the percolation threshold of the conducting phase, yielding large
ohmic losses that increase the absorptance above that of a corresponding
homogeneous film. Optimizing the thickness of the film to maximize its
transmittance above the percolation threshold of the conductive phase we
obtained a film with transmittance T = 0.41 and a sheet resistance
$R_{\square}^{\mathrm{max}}\approx2.7\Omega$. We also analyze the observed
emission frequency shift of porous silicon electroluminescent devices when Ag
films are used as solid electrical contacts in replacement of electrolytic
ones.


title: Dinv and Area

abstract:
  We give a new combinatorial proof of the well known result that the dinv of
an $(m,n)$-Dyck path is equal to the area of its sweep map image. The first
proof of this remarkable identity for co-prime $(m,n)$ is due to Loehr and
Warrington. There is also a second proof (in the co-prime case) due to Gorsky
and Mazin and a third proof due to Mazin.


title:
Weak Subordination of Multivariate L\'evy Processes and Variance
  Generalised Gamma Convolutions

abstract:
  Subordinating a multivariate L\'evy process, the subordinate, with a
univariate subordinator gives rise to a pathwise construction of a new L\'evy
process, provided the subordinator and the subordinate are independent
processes. The variance-gamma model in finance was generated accordingly from a
Brownian motion and a gamma process. Alternatively, multivariate subordination
can be used to create L\'evy processes, but this requires the subordinate to
have independent components. In this paper, we show that there exists another
operation acting on pairs $(T,X)$ of L\'evy processes which creates a L\'evy
process $X\odot T$. Here, $T$ is a subordinator, but $X$ is an arbitrary L\'evy
process with possibly dependent components. We show that this method is an
extension of both univariate and multivariate subordination and provide two
applications. We illustrate our methods giving a weak formulation of the
variance-$\alpha$-gamma process that exhibits a wider range of dependence than
using traditional subordination. Also, the variance generalised gamma
convolution class of L\'evy processes formed by subordinating Brownian motion
with Thorin subordinators is further extended using weak subordination.


title: Laplacian Distribution and Domination

abstract:
  Let $m_G(I)$ denote the number of Laplacian eigenvalues of a graph $G$ in an
interval $I$, and let $\gamma(G)$ denote its domination number. We extend the
recent result $m_G[0,1) \leq \gamma(G)$, and show that isolate-free graphs also
satisfy $\gamma(G) \leq m_G[2,n]$. In pursuit of better understanding Laplacian
eigenvalue distribution, we find applications for these inequalities. We relate
these spectral parameters with the approximability of $\gamma(G)$, showing that
$\frac{\gamma(G)}{m_G[0,1)} \not\in O(\log n)$. However, $\gamma(G) \leq m_G[2,
n] \leq (c + 1) \gamma(G)$ for $c$-cyclic graphs, $c \geq 1$. For trees $T$,
$\gamma(T) \leq m_T[2, n] \leq 2 \gamma(G)$.


title: Magnetoelectric Response in Multiferroic SrFe12O19 Ceramics

abstract:
  We report here the realization of ferroelectricity, ferromagnetism and
magnetocapacitance effect in SrFe12O19 ceramics at room temperature. The
ceramics demonstrate a saturated polarization hysteresis loop, two I-V peaks
and large anomaly of dielectric constant near Curie temperature. These
evidences confirmed the ferroelectricity of SrFe12O19 ceramics after annealing
in O2 atmosphere. The remnant polarization of the SrFe12O19 ceramic is 103
{\mu}C/cm2. The material also exhibits strong ferromagnetic characterization,
the coercive field and remnant magnetic moment are 6192Oe and 35.8emu/g,
respectively. Subsequent annealing SrFe12O19 ceramics in O2 not only reveals
its innate ferroelectricity but also improves the ferromagnetic properties
through transforming Fe2+ into Fe3+. By applying a magnetic field, the
capacitance demonstrates remarkable change along with B field, the maximum
relative change of dielectric constant is 1174%, which reflects a giant
magnetocapacitance effect in SrFe12O19. These combined functional responses in
SrFe12O19 ceramics opens substantial possibilities for applications in novel
electric devices.


title:
An efficient preconditioner for the fast simulation of a 2D Stokes flow
  in porous media

abstract:
  We consider an efficient preconditioner for boundary integral equation (BIE)
formulations of the two-dimensional Stokes equations in porous media. While
BIEs are well-suited for resolving the complex porous geometry, they lead to a
dense linear system of equations that is computationally expensive to solve for
large problems. This expense is further amplified when a significant number of
iterations is required in an iterative Krylov solver such as GMRES. In this
paper, we apply a fast inexact direct solver, the inverse fast multipole method
(IFMM), as an efficient preconditioner for GMRES. This solver is based on the
framework of $\mathcal{H}^{2}$-matrices and uses low-rank compressions to
approximate certain matrix blocks. It has a tunable accuracy $\varepsilon$ and
a computational cost that scales as $\mathcal{O} (N \log^2 1/\varepsilon)$. We
discuss various numerical benchmarks that validate the accuracy and confirm the
efficiency of the proposed method. We demonstrate with several types of
boundary conditions that the preconditioner is capable of significantly
accelerating the convergence of GMRES when compared to a simple block-diagonal
preconditioner, especially for pipe flow problems involving many pores.


title: Perturbations and quantum relaxation

abstract:
  We investigate whether small perturbations can cause relaxation to quantum
equilibrium over very long timescales. We consider in particular a
two-dimensional harmonic oscillator, which can serve as a model of a field mode
on expanding space. We assume an initial wave function with small perturbations
to the ground state. We present evidence that the trajectories are highly
confined so as to preclude relaxation to equilibrium even over very long
timescales. Cosmological implications are briefly discussed.


title: The transformation laws of algebraic theta functions

abstract:
  We give a comprehensive treatment of the transformation laws of theta
functions from an algebro-geometric perspective, that is, in terms of moduli of
abelian schemes. This is accomplished by introducing geometric notions of
theta-descent structures, metaplectic stacks, and bundles of half-forms, whose
analytic incarnations underlie different aspects of the classical
transformation laws. As an application, we lay the foundations for a geometric
theory of modular forms of half-integral weight and, more generally, for
modular forms taking values in the Weil representation. We discuss further
applications to the algebraic theory of Jacobi forms and to the theory of
determinant bundles of abelian schemes.


title: On biholomorphisms between bounded quasi-Reinhardt domains

abstract:
  In this paper, we define what is called a quasi-Reinhardt domain and study
biholomorphisms between such domains. We show that all biholomorphisms between
two bounded quasi-Reinhardt domains fixing the origin are polynomial mappings,
and we give a uniform upper bound for the degree of such polynomial mappings.
In particular, we generalize the classical Cartan's linearity theorem for
circular domains to quasi-Reinhardt domains.


title:
Classical Universe emerging from quantum cosmology without horizon and
  flatness problems

abstract:
  We apply the complex de Broglie-Bohm formulation of quantum mechanics [1] to
a spatially closed homogeneous and isotropic early Universe whose matter
content are radiation and dust perfect fluids. We then show that an expanding
classical Universe can emerge from an oscillating (with complex scale factor)
quantum Universe without singularity. Furthermore, the Universe obtained in
this process has no horizon or flatness problems.


title: Critical phenomena of regular black holes in anti-de Sitter space-time

abstract:
  In General Relativity coupled to a non-linear electromagnetic field, together
with a negative cosmological constant, we obtain the general static spherical
symmetric black hole solution with magnetic charges, which is asymptotic to
anti-de Sitter (AdS) space-times. In particular, for a degenerate case the
solution becomes a Hayward-AdS black hole, which is regular everywhere in the
full space-time. The existence of such a regular black hole solution preserves
the weak energy condition while the strong energy condition is violated. We
then derive the first law and the Smarr formula of the black hole solution. We
further discuss its thermodynamic properties and study the critical phenomena
in the extended phase space where the cosmological constant is treated as a
thermodynamic variable as well as the parameter associated with the non-linear
electrodynamics. We obtain many interesting results such as: the Maxwell's
equal area law in the $P-V$ (or $S-T$) diagram is violated and consequently the
critical point $(T_*\,,P_*)$ of the first order small-large black hole
transition does not coincide with the inflection point ($T_c\,,P_c$) of the
isotherms; the Clapeyron equation describing the coexistence curve of the Van
der Waals (vdW) fluid is no longer valid; the heat capacity at constant
pressure is finite at the critical point; the various exponents near the
critical point are also different from those of the vdW fluid.


title:
Lattices in crystalline representations and Kisin modules associated
  with iterate extensions

abstract:
  Cais and Liu extended the theory of Kisin modules and crystalline
representations to allow more general coefficient fields and lifts of
Frobenius. Based on their theory, we classify lattices in crystalline
representations by Kisin modules with additional structures under a Cais-Liu's
setting. Furthermore, we give a geometric interpretation of Kisin modules of
height one in terms of Dieudonn\'e crystals of $p$-divisible groups, and show a
full faithfulness theorem for a restriction functor on torsion crystalline
representations.


title: A Few Benchmark Test Cases for Higher-order Euler Solvers

abstract:
  There have been great efforts on the development of higher-order numerical
schemes for compressible Euler equations. The traditional tests mostly
targeting on the strong shock interactions alone may not be adequate to test
the performance of higher-order schemes. This study will introduce a few test
cases with a wide range of wave structures for testing higher-order schemes. As
reference solutions, all test cases will be calculated by our recently
developed two-stage fourth-order gas-kinetic scheme (GKS). All examples are
selected so that the numerical settings are very simple and any high order
accurate scheme can be straightly used for these test cases, and compare their
performance with the GKS solutions. The examples include highly oscillatory
solutions and the large density ratio problem in one dimensional case;
hurricane-like solutions, interactions of planar contact discontinuities (the
composite of entropy wave and vortex sheets) sheets with large Mach number
asymptotic, interaction of planar rarefaction waves with transition from
continuous flows to the presence of shocks, and other types of interactions of
two-dimensional planar waves. The numerical results from the fourth-order
gas-kinetic scheme provide reference solutions only. These benchmark test cases
will help CFD developers to validate and further develop their schemes to a
higher level of accuracy and robustness.


title:
Polarization- and frequency-tunable microwave circuit for selective
  excitation of nitrogen-vacancy spins in diamond

abstract:
  We report on a planar microwave resonator providing arbitrarily polarized
oscillating magnetic fields that enable selective excitation of the electronic
spins of nitrogen-vacancy (NV) centers in diamond. The polarization plane is
parallel to the surface of diamond, which makes the resonator fully compatible
with (111)-oriented diamond. The field distribution is spatially uniform in a
circular area with a diameter of 4 mm, and a near-perfect circular polarization
is achieved. We also demonstrate that the original resonance frequency of 2.8
GHz can be varied in the range of 2-3.2 GHz by introducing varactor diodes that
serve as variable capacitors.


title: Parallel Dynamics Computation using Prefix Sum Operations

abstract:
  We propose a new parallel framework for fast computation of inverse and
forward dynamics of articulated robots based on prefix sums (scans). We
re-investigate the well-known recursive Newton-Euler formulation of robot
dynamics and show that the forward-backward propagation process for robot
inverse dynamics is equivalent to two scan operations on certain semigroups. We
show that the state-of-the-art forward dynamics algorithms may almost
completely be cast into a sequence of scan operations, with unscannable parts
clearly identified. This suggests a serial-parallel hybrid approach for systems
with a moderate number of links. We implement our scan based algorithms on
Nvidia CUDA platform with performance compared with multithreading CPU-based
recursive algorithms; a significant level of acceleration is demonstrated.


title: Mean curvature flow with free boundary - Type 2 singularities

abstract:
  In this paper we give sufficient conditions that guarantee the meancurvature
flow with free boundary on an embedded rotationally symmetric double cone
develops a Type 2 curvature singularity. We additionally prove that Type 0
singularities may only occur at infinity.


title: Tsallis Regularized Optimal Transport and Ecological Inference

abstract:
  Optimal transport is a powerful framework for computing distances between
probability distributions. We unify the two main approaches to optimal
transport, namely Monge-Kantorovitch and Sinkhorn-Cuturi, into what we define
as Tsallis regularized optimal transport (\trot). \trot~interpolates a rich
family of distortions from Wasserstein to Kullback-Leibler, encompassing as
well Pearson, Neyman and Hellinger divergences, to name a few. We show that
metric properties known for Sinkhorn-Cuturi generalize to \trot, and provide
efficient algorithms for finding the optimal transportation plan with formal
convergence proofs. We also present the first application of optimal transport
to the problem of ecological inference, that is, the reconstruction of joint
distributions from their marginals, a problem of large interest in the social
sciences. \trot~provides a convenient framework for ecological inference by
allowing to compute the joint distribution --- that is, the optimal
transportation plan itself --- when side information is available, which is
\textit{e.g.} typically what census represents in political science.
Experiments on data from the 2012 US presidential elections display the
potential of \trot~in delivering a faithful reconstruction of the joint
distribution of ethnic groups and voter preferences.


title: Druse-Induced Morphology Evolution in Retinal Pigment Epithelium

abstract:
  The retinal pigment epithelium (RPE) is a key site of pathogenesis for many
retina diseases. The formation of drusen in the retina is characteristic of
retinal degeneration. We investigate morphological changes in the RPE in the
presence of soft drusen using an integrated experimental and modeling approach.
We collect RPE flat mount images from donated human eyes and develop 1)
statistical tools to quantify the images and 2) a cell-based model to simulate
the morphology evolution. We compare three different mechanisms of RPE repair
evolution, cell apoptosis, cell fusion, and expansion, and Simulations of our
RPE morphogenesis model quantitatively reproduce deformations of human RPE
morphology due to drusen, suggesting that a purse-string mechanism is
sufficient to explain how RPE heals cell loss caused by drusen-damage. We found
that drusen beneath tissue promote cell death in a number that far exceeds the
cell numbers covering the drusen. Tissue deformations are studied using area
distributions, Voronoi domains and a texture tensor.


title:
Indecomposables with smaller cohomological length in the derived
  category of gentle algebras

abstract:
  Bongartz and Ringel proved that there is no gaps in the sequence of lengths
of indecomposable modules for the finite-dimensional algebras over
algebraically closed fields. The present paper mainly study this "no gaps"
theorem for the bounded derived module category $D^b(A)$ of a gentle algebra
$A$: if there is an indecomposable object in $D^b(A)$ of cohomological length
$l>1$, then there exists an indecomposable with cohomological length $l-1$.