  Deep VLT optical spectroscopy, HST+ACS (GOODS) imaging and VLA observations
are used to unveil the nature of a complete sample of 47 EROs with R-Ks>5 and
Ks<20. The spectroscopic redshift completeness is 62%. Morphological
classification was derived for each ERO through visual inspection and surface
brightness profile fitting. Three main ERO morphological types are found: E/S0
galaxies (30-37%), spiral-like (24-46%) and irregular systems (17-39%). The
only ERO detected in the radio is likely to host an obscured AGN. The average
radio luminosity of the star-forming EROs undetected in the radio implies star
formation rates of the order of 33 Msun yr^-1. The colors, redshifts and masses
of the E/S0 galaxy subsample imply a minimum formation redshift z_f \sim 2.
With this z_f there is enough time to have old and massive stellar spheroids
already assembled at z \sim 1. We verify that the R-Ks vs. J-Ks color diagram
is efficient in segregating old and dusty-star-forming EROs.


  In this paper we establish the Mackey formula for groupoids, extending the
well known formula in abstract groups context. This formula involves the notion
of groupoid-biset, its orbit set and the tensor product over groupoids, as well
as cosets by subgroupoids.


  We consider two spin-1/2 particles with isotropic Heisenberg interaction, as
the working substance of a quantum heat engine. We observe a frictional effect
on the adiabatic branches of the heat cycle, which arises due to an
inhomogeneous driving at a finite rate of the external magnetic field. The
frictional effect is characterized by entropy production in the system and
reduction in the work extracted. Corresponding to a sudden and a very slow
driving, we find expressions for the lower and upper bounds of work that can be
extracted on the adiabatic branches. These bounds are also confirmed with
numerical simulations of the corresponding Liouville-von Neumann equation.


  We study the formation and destruction of molecules in the ejecta of
Population III supernovae (SNe) using a chemical kinetic approach to follow the
evolution of molecular abundances from day 100 to day 1000 after explosion. The
chemical species included range from simple di-atomic molecules to more complex
dust precursor species. All relevant chemical processes that are unique to the
SN environment are considered. Our work focuses on zero-metallicity progenitors
with masses of 20, 170, and 270 Msun, and we study the effect of different
levels of heavy element mixing and the inward diffusion of hydrogen on the
ejecta chemistry. We show that the ejecta chemistry does not reach a steady
state within the relevant time-span for molecule formation. The primary species
formed are O2, CO, SiS, and SO. The SiO, formed as early as 200 days after
explosion, is rapidly depleted by the formation of silica molecular precursors
in the ejecta. The rapid conversion of CO to C2 and its thermal fractionation
at temperatures above 5000 K allow for the formation of carbon chains in the
oxygen-rich zone of the unmixed models, providing an important pathway for the
formation of carbon dust in hot environments where the C/O ratio is less than
1. We show that the fully-mixed ejecta of a 170 Msun progenitor synthesizes
11.3 Mun of molecules whereas 20 Msun and 270 Msun progenitors produce 0.78,
and 3.2 Msun of molecules, respectively. The admixing of 10 % of hydrogen into
the fully-mixed ejecta of the 170 Msun progenitor increases its molecular yield
to ~ 47Msun. The unmixed ejecta of a 170 Msun progenitor supernova without
hydrogen penetration synthesizes ~37 Msun of molecules, whereas its 20 Msun
counterpart produces ~ 1.2 Msun. Finally, we discuss the cosmological
implication of molecule formation by Pop. III SNe in the early universe.


  We discuss the properties of a large number N of one-dimensional (bounded)
locally periodic potential barriers in a finite interval. We show that the
transmission coefficient, the scattering cross section $\sigma$, and the
resonances of $\sigma$ depend sensitively upon the ratio of the total spacing
to the total barrier width. We also show that a time dependent wave packet
passing through the system of potential barriers rapidly spreads and deforms, a
criterion suggested by Zaslavsky for chaotic behaviour. Computing the spectrum
by imposing (large) periodic boundary conditions we find a Wigner type
distribution. We investigate also the S-matrix poles; many resonances occur for
certain values of the relative spacing between the barriers in the potential.


  We study two-component bosonic systems with strong inter-species and
vanishing intra-species interactions. A new class of exact eigenstates is found
with energies that are {\it not} sums of the single-particle energies with wave
functions that have the characteristic feature that they vanish over extended
regions of coordinate space. This is demonstrated in an analytically solvable
model for three equal mass particles, two of which are identical bosons, which
is exact in the strongly-interacting limit. We numerically verify our results
by presenting the first application of the stochastic variational method to
this kind of system. We also demonstrate that the limit where both inter- and
intra-component interactions become strong must be treated with extreme care as
these limits do not commute. Moreover, we argue that such states are generic
also for general multi-component systems with more than three particles. The
states can be probed using the same techniques that have recently been used for
fermionic few-body systems in quasi-1D.


  The focus of this paper is the study of the regularity properties of the time
harmonic Maxwell's equations with anisotropic complex coefficients, in a
bounded domain with $C^{1,1}$ boundary. We assume that at least one of the
material parameters is $W^{1,3+\delta}$ for some $\delta>0$. Using regularity
theory for second order elliptic partial differential equations, we derive
$W^{1,p}$ estimates and H\"older estimates for electric and magnetic fields up
to the boundary. We also derive interior estimates in bi-anisotropic media.


  On a Peano continuum, all local stable and unstable components of a
continuum-wise expansive homeomorphism are non trivial. In particular, there is
sensitive dependence on initial conditions.
  This generalizes results in \cite{h,l} about lack of Lyapunov stable points
(weak sinks) and existence of non trivial stable and unstable components for
expansive homeomorphisms on Peano continua. We also use this fact to generalize
a result in \cite{ktt}: a Peano curve $X$ admitting a continuum-wise expansive
homeomorphism is nowhere rim-countable. However, it is not resolved the
question of whether such a dynamics could be possible in a locally planar Peano
curve. Some other questions are posed.


  We have studied the single particle heat engine and refrigerator driven by
time asymmetric protocol of finite duration. Our system consists of a particle
in a harmonic trap with time-periodic strength that drives the particle
cyclically between two baths. Each cycle consists of two isothermal steps at
different temperatures and two adiabatic steps connecting them. The system
works in irreversible mode of operation even in the quasistatic regime. This is
indicated by finite entropy production even in the large cycle time limit.
Consequently, Carnot efficiency for heat engine or Carnot Co-efficient of
performance (COP) for refrigerators are not achievable. We further analysed the
phase diagram of heat engines and refrigerators. They are sensitive to
time-asymmetry of the protocol. Phase diagram shows several interesting
features, often counterintuitive. The distribution of stochastic efficiency and
COP is broad and exhibits power law tails.


  Learned sparse retrieval (LSR) is a family of neural methods that encode
queries and documents into sparse lexical vectors that can be indexed and
retrieved efficiently with an inverted index. We explore the application of LSR
to the multi-modal domain, with a focus on text-image retrieval. While LSR has
seen success in text retrieval, its application in multimodal retrieval remains
underexplored. Current approaches like LexLIP and STAIR require complex
multi-step training on massive datasets. Our proposed approach efficiently
transforms dense vectors from a frozen dense model into sparse lexical vectors.
We address issues of high dimension co-activation and semantic deviation
through a new training algorithm, using Bernoulli random variables to control
query expansion. Experiments with two dense models (BLIP, ALBEF) and two
datasets (MSCOCO, Flickr30k) show that our proposed algorithm effectively
reduces co-activation and semantic deviation. Our best-performing sparsified
model outperforms state-of-the-art text-image LSR models with a shorter
training time and lower GPU memory requirements. Our approach offers an
effective solution for training LSR retrieval models in multimodal settings.
Our code and model checkpoints are available at
github.com/thongnt99/lsr-multimodal


  We present the results of ISO SWS and LWS grating scans towards the three
brightest members of the BD+40 4124 group in the infrared: BD+40 4124 (B2Ve),
LkHalpha 224 (A7e) and the embedded source LkHalpha 225. Emission from the pure
rotational lines of H_2, from ro-vibrational transitions of CO, from PAHs, from
H I recombination lines and from the infrared fine structure lines of [Fe II],
[Si II], [S I], [O I], [O III] and [C II] was detected. These emission lines
arise in the combination of a low-density (approx 10^2 cm^-3) H II region with
a clumpy PDR in the case of BD+40 4124. The lower transitions of the infrared H
I lines observed in BD+40 4124 are optically thick; most likely they arise in
either a dense wind or a circumstellar disk. This same region is also
responsible for the optical H I lines and the radio continuum emission. In the
lines of sight towards LkHalpha 224 and LkHalpha 225, the observed emission
lines arise in a non-dissociative shock produced by a slow (approx 20 km/s)
outflow arising from LkHalpha 225. Toward LkHalpha 225 we also observe a
dissociative shock, presumably located closer to the outflow source than the
non-dissociative shock. In the line of sight towards LkHalpha 225 we observed
absorption features due to solid water ice and amorphous silicates, and due to
gas-phase H_2O, CO and CO_2. No solid CO_2 was detected towards LkHalpha 225,
making this the first line of sight where the bulk of the CO_2 is in the
gas-phase.


  The non-linear stress-strain relation for crosslinked polymer networks is
studied using molecular dynamics simulations. Previously we demonstrated the
importance of trapped entanglements in determining the elastic and relaxational
properties of networks. Here we present new results for the stress versus
strain for both dry and swollen networks. Models which limit the fluctuations
of the network strands like the tube model are shown to describe the stress for
both elongation and compression. For swollen networks, the total modulus is
found to decrease like (V_0/V)^{2/3} and goes to the phantom model result only
for short strand networks.


  In this paper, we generally formulate the dynamics prediction problem of
various network systems (e.g., the prediction of mobility, traffic and
topology) as the temporal link prediction task. Different from conventional
techniques of temporal link prediction that ignore the potential non-linear
characteristics and the informative link weights in the dynamic network, we
introduce a novel non-linear model GCN-GAN to tackle the challenging temporal
link prediction task of weighted dynamic networks. The proposed model leverages
the benefits of the graph convolutional network (GCN), long short-term memory
(LSTM) as well as the generative adversarial network (GAN). Thus, the dynamics,
topology structure and evolutionary patterns of weighted dynamic networks can
be fully exploited to improve the temporal link prediction performance.
Concretely, we first utilize GCN to explore the local topological
characteristics of each single snapshot and then employ LSTM to characterize
the evolving features of the dynamic networks. Moreover, GAN is used to enhance
the ability of the model to generate the next weighted network snapshot, which
can effectively tackle the sparsity and the wide-value-range problem of edge
weights in real-life dynamic networks. To verify the model's effectiveness, we
conduct extensive experiments on four datasets of different network systems and
application scenarios. The experimental results demonstrate that our model
achieves impressive results compared to the state-of-the-art competitors.


  With the release of Amazon Alexa and the first Amazon Echo device, the
company revolutionised the smart home. It allowed their users to communicate
with, and control, their smart home ecosystem purely using voice commands.
However, this also means that Amazon processes and stores a large amount of
personal data about their users, as these devices are always present and always
listening in peoples' private homes. That makes this data a valuable source of
evidence for investigators performing digital forensics. The Alexa Voice
Service uses a series of APIs for communication between clients and the Amazon
cloud. These APIs return a wide range of data related to the functionality of
the device used.
  The first goal of this research was to clarify exactly what kind of
information about the user is stored and accessible through these APIs. To do
this, a combination of literature review and exploratory analysis was used to
establish a list of all relevant APIs. Then, possible artefacts and conclusions
to be drawn from their responses were identified and presented. Lastly, the
perspective of the users was taken, and options for improving their privacy
were reviewed. Specifically, the history of interaction between the user and
Alexa is available through multiple APIs, and there are several options to
delete it. It was determined that these options have different behaviours and
that most of them do not remove all data related to user interaction.


  The forces between colloidal particles at a decane-water interface, in the
presence of low concentrations of a monovalent salt (NaCl) and of the
surfactant sodium dodecylsulfate (SDS) in the aqueous subphase, have been
studied using laser tweezers. In the absence of electrolyte and surfactant,
particle interactions exhibit a long-range repulsion, yet the variation of the
interaction for different particle pairs is found to be considerable. Averaging
over several particle pairs was hence found to be necessary to obtain reliable
assessment of the effects of salt and surfactant. It has previously been
suggested that the repulsion is consistent with electrostatic interactions
between a small number of dissociated charges in the oil phase, leading to a
decay with distance to the power -4 and an absence of any effect of electrolyte
concentration. However, the present work demonstrates that increasing the
electrolyte concentration does yield, on average, a reduction of the magnitude
of the interaction force with electrolyte concentration. This implies that
charges on the water side also contribute significantly to the electrostatic
interactions. An increase in the concentration of SDS leads to a similar
decrease of the interaction force. Moreover the repulsion at fixed SDS
concentrations decreases over longer times. Finally, measurements of three-body
interactions provide insight into the anisotropic nature of the interactions.
The unique time-dependent and anisotropic interactions between particles at the
oil-water interface allow tailoring of the aggregation kinetics and structure
of the suspension structure.


  The New Luyten Two-Tenths catalog contains a large number of high-proper
motion white dwarf candidates that remain to be spectroscopically confirmed. We
present new spectroscopic observations as well as SDSS archival spectra of 49
white dwarf candidates which have been selected from the revised NLTT catalog
of Salim & Gould 2003. Out of these, 34 are cool DA white dwarfs with
temperatures ranging from approximately 5000 K up to 11690 K, and 11 are DC
white dwarfs with temperatures ranging from 4300 K (NLTT 18555) up to 11000 K.
Three of the DA white dwarfs also display abundances of heavy elements (NLTT
3915, NLTT 44986 and NLTT 43806) and one is a cool magnetic white dwarf (NLTT
44447) with an estimated magnetic field strength of 1.3 MG. We also present a
new cool DQ white dwarf (NLTT 31347) with an estimated temperature of 6250 K.
We supplement our sample with SDSS ugriz photometry for a fraction of the newly
identified white dwarfs. A kinematical study of this sample of white dwarfs,
characterized by proper motions ranging from 0.136 to 0.611 arcsec per yr
suggest that they belong to the thin disk population.


  Recently, deep learning-based language models have significantly enhanced
text-to-SQL tasks, with promising applications in retrieving patient records
within the medical domain. One notable challenge in such applications is
discerning unanswerable queries. Through fine-tuning model, we demonstrate the
feasibility of converting medical record inquiries into SQL queries.
Additionally, we introduce an entropy-based method to identify and filter out
unanswerable results. We further enhance result quality by filtering
low-confidence SQL through log probability-based distribution, while
grammatical and schema errors are mitigated by executing queries on the actual
database. We experimentally verified that our method can filter unanswerable
questions, which can be widely utilized even when the parameters of the model
are not accessible, and that it can be effectively utilized in practice.


  The average cost optimality is known to be a challenging problem for
partially observable stochastic control, with few results available beyond the
finite state, action, and measurement setup, for which somewhat restrictive
conditions are available. In this paper, we present explicit and easily
testable conditions for the existence of solutions to the average cost
optimality equation where the state space is compact. In particular, we present
a new contraction based analysis, which is new to the literature to our
knowledge, building on recent regularity results for non-linear filters. Beyond
establishing existence, we also present several implications of our analysis
that are new to the literature: (i) robustness to incorrect priors (ii) near
optimality of policies based on quantized approximations, (iii) near optimality
of policies with finite memory, and (iv) convergence in Q-learning. In addition
to our main theorem, each of these represents a novel contribution for average
cost criteria.


  We show that the cosmological abundance of string axions is much smaller than
naive estimates if the Hubble scale of inflation, $H_{\rm inf}$, is
sufficiently low (but can still be much higher than the axion masses) and if
the inflation lasts sufficiently long. The reason is that the initial
misalignment angles of the string axions follow the Bunch-Davies distribution
peaked at the potential minima. As a result, the cosmological moduli problem
induced by the string axions can be significantly relaxed by low-scale
inflation, and astrophysical and cosmological bounds are satisfied over a wide
range of the mass without any fine-tuning of the initial misalignment angles.
Specifically, the axion with its decay constant $f_\phi = 10^{16}$\,GeV
satisfies the bounds over $10^{-18}{\rm \, eV} \lesssim m_\phi \lesssim
10{\rm\,TeV}$ for $H_{\rm inf} \lesssim 10{\rm\,keV}- 10^{6}$\,{\rm GeV}. We
also discuss cases with multiple axions and the QCD axion.


  Besides the conventional strong and electromagnetic decay modes, the
$J/{\psi}$ particle can also decay via the weak interaction in the standard
model. In this paper, nonleptonic $J/{\psi}$ ${\to}$ $D_{s,d}{\pi}$, $D_{s,d}K$
weak decays, corresponding to the externally emitted virtual $W$ boson process,
are investigated with the perturbative QCD approach. It is found that branching
ratio for the Cabibbo-favored $J/{\psi}$ ${\to}$ $D_{s}{\pi}$ decay can reach
up to ${\cal O}(10^{-10})$, which might be potentially measurable at the future
high-luminosity experiments.


  We apply the configuration-interaction method to calculate the spectra of
two-component Fermi systems in a harmonic trap, studying the convergence of the
method at the unitary interaction limit. We find that for a fixed
regularization of the two-body interaction the convergence is exponential or
better in the truncation parameter of the many-body space. However, the
conventional regularization is found to have poor convergence in the
regularization parameter, with an error that scales as a low negative power of
this parameter. We propose a new regularization of the two-body interaction
that produces exponential convergence for systems of three and four particles.
  From the systematics, we estimate the ground-state energy of the
four-particle system to be (5.05 +- 0.024)hbar omega.


  We study bitangents of non-smooth tropical plane quartics. Our main result is
that with appropriate multiplicities, every such curve has 7 equivalence
classes of bitangent lines. Moreover, the multiplicity of bitangent lines
varies continuously in families of tropical plane curves.


  In this paper we obtain some sophisticated combinatorial congruences
involving binomial coefficients and confirm two conjectures of the author and
Davis. They are closely related to our investigation of the periodicity of the
sequence $\sum_{j=0}^l{l\choose j}S(j,m)a^{l-j}(l=m,m+1,...)$ modulo a prime
$p$, where $a$ and $m>0$ are integers, and those $S(j,m)$ are Stirling numbers
of the second kind. We also give a new extension of Glaisher's congruence by
showing that $(p-1)p^{[\log_p m]}$ is a period of the sequence $\sum_{j=r(mod
p-1)}{l\choose j}S(j,m)(l=m,m+1,...)$ modulo $p$.


  Temporal-Difference (TD) learning is a general and very useful tool for
estimating the value function of a given policy, which in turn is required to
find good policies. Generally speaking, TD learning updates states whenever
they are visited. When the agent lands in a state, its value can be used to
compute the TD-error, which is then propagated to other states. However, it may
be interesting, when computing updates, to take into account other information
than whether a state is visited or not. For example, some states might be more
important than others (such as states which are frequently seen in a successful
trajectory). Or, some states might have unreliable value estimates (for
example, due to partial observability or lack of data), making their values
less desirable as targets. We propose an approach to re-weighting states used
in TD updates, both when they are the input and when they provide the target
for the update. We prove that our approach converges with linear function
approximation and illustrate its desirable empirical behaviour compared to
other TD-style methods.


  Heavy quark potentials are investigated at high temperatures. The temperature
range covered by the analysis extends from $T$ values just below the
deconfinement temperature up to about $4 T_c$ in the deconfined phase. We
simulated the pure gauge sector of QCD on lattices with temporal extents of 4,
6 and 8 with spatial volumes of $32^3$. On the smallest lattice a tree level
improved action was employed while in the other two cases the standard Wilson
action was used. Below $T_c$ we find a temperature dependent logarithmic term
contributing to the confinement potential and observe a string tension which
decreases with rising temperature but retains a finite value at the
deconfinement transition. Above $T_c$ the potential is Debye-screened, however
simple perturbative predictions do not apply.


  Oysters are an essential species in the Chesapeake Bay living ecosystem.
Oysters are filter feeders and considered the vacuum cleaners of the Chesapeake
Bay that can considerably improve the Bay's water quality. Many oyster
restoration programs have been initiated in the past decades and continued to
date. Advancements in robotics and artificial intelligence have opened new
opportunities for aquaculture. Drone-like ROVs with high maneuverability are
getting more affordable and, if equipped with proper sensory devices, can
monitor the oysters. This work presents our efforts for videography of the
Chesapeake bay bottom using an ROV, constructing a database of oysters,
implementing Mask R-CNN for detecting oysters, and counting their number in a
video by tracking them.


  In the light of the discovery of numerous (almost) dark galaxies from the
ALFALAFA and LITTLE THINGS surveys, we revisit the predictions of Jimenez et
al. 1997, based on the Toomre stability of rapidly-spinning gas disks. We have
updated the predictions for $\Lambda$CDM with parameters given by Planck18,
computing the expected number densities of dark objects, and their spin
parameter and mass distributions. Comparing with the data is more challenging,
but where the spins are more reliably determined, the spins are close to the
threshold for disks to be stable according to the Toomre criterion, where the
expected number density is highest, and reinforces the concept that there is a
bias in the formation of luminous galaxies based on the spin of their parent
halo.


  Event Horizon Telescope (EHT) observations at 230 GHz are combined with Very
Long Baseline Interferometry (VLBI) observations at 86 GHz and high resolution
Hubble Space Telescope optical observations in order to constrain the broadband
spectrum of the emission from the base of the jet in M87. The recent VLBI
observations of Hada et al provide much stricter limits on the 86 GHz
luminosity and component acceleration in the jet base than was available to
previous modelers. They reveal an almost hollow jet on sub-mas scales. Thus,
tubular models of the jet base emanating from the innermost accretion disk are
considered within the region responsible for the EHT correlated flux. There is
substantial synchrotron self absorbed opacity at 86 GHz. A parametric analysis
indicates that the jet dimensions and power depend strongly on the 86 GHz flux
density and the black hole spin, but weakly on other parameters such as jet
speed, 230 GHz flux density and optical flux. The entire power budget of the
M87 jet, $\lesssim 10^{44}\rm{ergs/sec}$, can be accommodated by the tubular
jet. No invisible, powerful spine is required. Even though this analysis never
employs the resolution of the EHT, the spectral shape implies a dimension
transverse to the jet direction of 12-21 $\mu \rm{as}$ ($\sim$24-27$\, \mu
\rm{as}$) for $0.99 > a/M > 0.95$ ($a/M\sim 0.7 $), where $M$ is the mass and
$a$ is the angular momentum per unit mass of the central black hole.


  The odd-mass $^{117}$Sn nucleus was investigated in nuclear resonance
fluorescence experiments up to an endpoint energy of the incident photon
spectrum of 4.1 MeV at the bremsstrahlung facility of the Stuttgart University.
More than 50 mainly hitherto unknown levels were found. From the measurement of
the scattering cross sections model independent absolute electric dipole
excitation strengths were extracted. The measured angular distributions
suggested the spins of 11 excited levels. Quasi-particle phonon model
calculations including a complete configuration space were performed for the
first time for a heavy odd-mass spherical nucleus. These calculations give a
clear insight in the fragmentation and distribution of the $E1$, $M1$, and $E2$
excitation strength in the low energy region. It is proven that the $1^{-}$
component of the two-phonon $[2^{+}_{1} \otimes 3^{-}_{1}]$ quintuplet built on
top of the $1/2^{+}$ ground state is strongly fragmented. The theoretical
calculations are consistent with the experimental data.


  A web of cohomological facts relates quantum error correction,
measurement-based quantum computation, symmetry protected topological order and
contextuality. Here we extend this web to quantum computation with magic
states. In this computational scheme, the negativity of certain
quasiprobability functions is an indicator for quantumness. However, when
constructing quasiprobability functions to which this statement applies, a
marked difference arises between the cases of even and odd local Hilbert space
dimension. At a technical level, establishing negativity as an indicator of
quantumness in quantum computation with magic states relies on two properties
of the Wigner function: their covariance with respect to the Clifford group and
positive representation of Pauli measurements. In odd dimension, Gross' Wigner
function -- an adaptation of the original Wigner function to
odd-finite-dimensional Hilbert spaces -- possesses these properties. In even
dimension, Gross' Wigner function doesn't exist. Here we discuss the broader
class of Wigner functions that, like Gross', are obtained from operator bases.
We find that such Clifford-covariant Wigner functions do not exist in any even
dimension, and furthermore, Pauli measurements cannot be positively represented
by them in any even dimension whenever the number of qudits is n>=2. We
establish that the obstructions to the existence of such Wigner functions are
cohomological.


  Using the HST ACS, we have obtained deep optical images reaching well below
the oldest main sequence turnoff in fields on the southeast minor-axis of the
Andromeda Galaxy, 35 kpc from the nucleus. These data probe the star formation
history in the extended halo of Andromeda -- that region beyond 30 kpc that
appears both chemically and morphologically distinct from the metal-rich,
highly-disturbed inner spheroid. The present data, together with our previous
data for fields at 11 and 21 kpc, do not show a simple trend toward older ages
and lower metallicities, as one might expect for populations further removed
from the obvious disturbances of the inner spheroid. Specifically, the mean
ages and [Fe/H] values at 11 kpc, 21 kpc, and 35 kpc are 9.7 Gyr and -0.65,
11.0 Gyr and -0.87, and 10.5 Gyr and -0.98, respectively. In the best-fit model
of the 35 kpc population, one third of the stars are younger than 10 Gyr, while
only ~10% of the stars are truly ancient and metal-poor. The extended halo thus
exhibits clear evidence of its hierarchical assembly, and the contribution from
any classical halo formed via early monolithic collapse must be small.


  This note is a correction of (statement and proof of) proposition 3.3.1 of
Toby Gee's preprint intitled *On the weights of mod p Hilbert modular forms*.
The aim is to compare Galois representations arising from extensions of some
group schemes (over the ring of integers of a p-adic field) endowed with a
descent data, and extensions of some crystalline representations with given
Hodge-Tate weights. The main tool of the proof is the theory of Breuil.


  The Heston stochastic volatility process is a degenerate diffusion process
where the degeneracy in the diffusion coefficient is proportional to the square
root of the distance to the boundary of the half-plane. The generator of this
process with killing, called the elliptic Heston operator, is a second-order,
degenerate-elliptic partial differential operator, where the degeneracy in the
operator symbol is proportional to the distance to the boundary of the
half-plane. In mathematical finance, solutions to the obstacle problem for the
elliptic Heston operator correspond to value functions for perpetual
American-style options on the underlying asset. With the aid of weighted
Sobolev spaces and weighted Holder spaces, we establish the optimal $C^{1,1}$
regularity (up to the boundary of the half-plane) for solutions to obstacle
problems for the elliptic Heston operator when the obstacle functions are
sufficiently smooth.


  In recent biomedical scientific problems, it is a fundamental issue to
integratively cluster a set of objects from multiple sources of datasets. Such
problems are mostly encountered in genomics, where data is collected from
various sources, and typically represent distinct yet complementary
information. Integrating these data sources for multi-source clustering is
challenging due to their complex dependence structure including directional
dependency. Particularly in genomics studies, it is known that there is certain
directional dependence between DNA expression, DNA methylation, and RNA
expression, widely called The Central Dogma.
  Most of the existing multi-view clustering methods either assume an
independent structure or pair-wise (non-directional) dependency, thereby
ignoring the directional relationship. Motivated by this, we propose a
copula-based multi-view clustering model where a copula enables the model to
accommodate the directional dependence existing in the datasets. We conduct a
simulation experiment where the simulated datasets exhibiting inherent
directional dependence: it turns out that ignoring the directional dependence
negatively affects the clustering performance. As a real application, we
applied our model to the breast cancer tumor samples collected from The Cancer
Genome Altas (TCGA).


  We present the results of a study of the temporal behaviour of several
diagnostic lines formed in the region of the accretion-disk/star interaction in
the three magnetic Herbig Ae stars HD101412, HD104237, and HD190073. More than
100 spectra acquired with the ISAAC, X-shooter, and CRIRES spectrographs
installed at the VLT-8m telescope (ESO, Chile), as well as at other
observatories (OHP, Crimean AO) were analyzed. The spectroscopic data were
obtained in the He I lambda10830, Pa gamma and He I lambda5876 lines. We found
that the temporal behaviour of the diagnostic lines in the spectra of all
program stars can be widely explained by a rotational modulation of the line
profiles generated by a local accretion flow. This result is in good agreement
with the predictions of the magnetospheric accretion model. For the first time,
the rotation period of HD104237 (P_rot = 5.37+-0.03 days), as well as the
inclination angle (i = 21+-4deg) were determined. Additional analysis of the
HARPSpol spectra of HD104237 and HD190073, taken from the ESO archive, with the
use of the SVD method shows that the magnetic field structure of HD190073 is
likely more complex than a simple dipole and contains a circumstellar
component. For the first time, the magnetic field of the secondary component of
the binary system HD104237 was also detected (<B_z> = 128+-10G).


  This paper presents a neural network based method Multi-Task Affect
Net(MTANet) submitted to the Affective Behavior Analysis in-the-Wild Challenge
in FG2020. This method is a multi-task network and based on SE-ResNet modules.
By utilizing multi-task learning, this network can estimate and recognize three
quantified affective models: valence and arousal, action units, and seven basic
emotions simultaneously. MTANet achieve Concordance Correlation
Coefficient(CCC) rates of 0.28 and 0.34 for valence and arousal, F1-score of
0.427 and 0.32 for AUs detection and categorical emotion classification.


  Active matter physics and swarm robotics have provided powerful tools for the
study and control of ensembles driven by internal sources. At the macroscale,
controlling swarms typically utilizes significant memory, processing power, and
coordination unavailable at the microscale, e.g., for colloidal robots, which
could be useful for fighting disease, fabricating intelligent textiles, and
designing nanocomputers. To develop principles that that can leverage physics
of interactions and thus can be utilized across scales, we take a two-pronged
approach: a theoretical abstraction of self-organizing particle systems and an
experimental robot system of active cohesive granular matter that intentionally
lacks digital electronic computation and communication, using minimal (or no)
sensing and control, to test theoretical predictions. We consider the problems
of aggregation, dispersion, and collective transport. As predicted by the
theory, as a parameter representing interparticle attraction increases, the
robots transition from a dispersed phase to an aggregated one, forming a dense,
compact collective. When aggregated, the collective can transport non-robot
"impurities" in their environment, thus performing an emergent task driven by
the physics underlying the transition. These results point to a fruitful
interplay between algorithm design and active matter robophysics that can
result in new nonequilibrium physics and principles for programming collectives
without the need for complex algorithms or capabilities.


  In the recent literature there has been a resurgence of interest in the
fourth-order field-theoretic model of Pais-Uhlenbeck \cite {Pais-Uhlenbeck 50
a}, which has not had a good reception over the last half century due to the
existence of {\em ghosts} in the properties of the quantum mechanical solution.
Bender and Mannheim \cite{Bender 08 a} were successful in persuading the
corresponding quantum operator to `give up the ghost'. Their success had the
advantage of making the model of Pais-Uhlenbeck acceptable to the physical
community and in the process added further credit to the cause of advancement
of the use of ${\cal PT} $ symmetry. We present a case for the acceptance of
the Pais-Uhlenbeck model in the context of Dirac's theory by providing an
Hamiltonian which is not quantum mechanically haunted. The essential point is
the manner in which a fourth-order equation is rendered into a system of
second-order equations. We show by means of the method of reduction of order
\cite {Nucci} that it is possible to construct an Hamiltonian which gives rise
to a satisfactory quantal description without having to abandon Dirac.


  We present a sensitivity study on the cubic and quartic self couplings in
double Higgs production via gluon fusion at hadron colliders. Considering the
relevant operators in the Standard Model Effective Field Theory up to dimension
eight, we calculate the dominant contributions up to two-loop level, where the
first dependence on the quartic interaction appears. Our approach allows to
study the independent variations of the two self couplings and to clearly
identify the terms necessary to satisfy gauge invariance and to obtain
UV-finite results order by order in perturbation theory. We focus on the $b
\bar b \gamma \gamma$ signature for simplicity and provide the expected bounds
for the cubic and quartic self couplings at the 14 TeV LHC with 3000 fb$^{-1}$
(HL-LHC) and for a future 100 TeV collider (FCC-100) with 30 ab$^{-1}$. We find
that while the HL-LHC will provide very limited sensitivity on the quartic self
coupling, precision measurements of double Higgs production at a FCC-100 will
offer the opportunity to set competitive bounds. We show that combining
information from double and triple Higgs production leads to significantly
improved prospects for the determination of the quartic self coupling.


  W.H. Woodin showed that if $\kappa_1 < \cdots < \kappa_n$ are strong
cardinals then two-step ${\bf\Sigma}^1_{n+3}$ generic absoluteness holds after
collapsing $2^{2^{\kappa_n}}$ to be countable. We show that this number can be
reduced to $2^{\kappa_n}$, and to $\kappa_n^+$ in the case $n = 1$, but cannot
be further reduced to $\kappa_n$.


  Projection effects, whereby galaxies along the line-of-sight to a galaxy
cluster are mistakenly associated with the cluster halo, present a significant
challenge for optical cluster cosmology. We use statistically representative
spectral coverage of luminous galaxies to investigate how projection effects
impact the low-redshift limit of the Sloan Digital Sky Survey (SDSS) redMaPPer
galaxy cluster catalogue. Spectroscopic redshifts enable us to differentiate
true cluster members from false positives and determine the fraction of
candidate cluster members viewed in projection. Our main results can be
summarized as follows: first, we show that a simple double-Gaussian model can
be used to describe the distribution of line-of-sight velocities in the
redMaPPer sample; second, the incidence of projection effects is substantial,
accounting for $\sim 16$ per cent of the weighted richness for the lowest
richness objects; third, projection effects are a strong function of richness,
with the contribution in the highest richness bin being several times smaller
than for low-richness objects; fourth, our measurement has a similar amplitude
to state-of-the-art models, but finds a steeper dependence of projection
effects on richness than these models; and fifth, the slope of the observed
velocity dispersion--richness relation, corrected for projection effects,
implies an approximately linear relationship between the true,
three-dimensional halo mass and three-dimensional richness. Our results provide
a robust, empirical description of the impact of projection effects on the SDSS
redMaPPer cluster sample and exemplify the synergies between optical imaging
and spectroscopic data for studies of galaxy cluster astrophysics and
cosmology.


  We consider the transport statistics of classical bistable systems driven by
noise. The stochastic path integral formalism is used to investigate the
dynamics and distribution of transmitted charge. Switching rates between the
two stable states are found from an instanton calculation, leading to an
effective two-state system on a long time scale. In the bistable current range,
the telegraph noise dominates the distribution, whose logarithm is found to be
universally described by a tilted ellipse.


  We implement a semi-analytic approach for stability analysis, addressing the
ongoing uncertainty about stability and structure of neutron star magnetic
fields. Applying the energy variational principle, a model system is displaced
from its equilibrium state. The related energy density variation is set up
analytically, whereas its volume integration is carried out numerically. This
facilitates the consideration of more realistic neutron star characteristics
within the model compared to analytical treatments. At the same time, our
method retains the possibility to yield general information about neutron star
magnetic field and composition structures that are likely to be stable. In
contrast to numerical studies, classes of parametrized systems can be studied
at once, finally constraining realistic configurations for interior neutron
star magnetic fields. We apply the stability analysis scheme on polytropic and
non-barotropic neutron stars with toroidal, poloidal and mixed fields testing
their stability in a Newtonian framework. Furthermore, we provide the
analytical scheme for dropping the Cowling approximation in an axisymmetric
system and investigate its impact. Our results confirm the instability of
simple magnetised neutron star models as well as a stabilisation tendency in
the case of mixed fields and stratification. These findings agree with
analytical studies whose spectrum of model systems we extend by lifting former
simplifications.


  In single star systems like our own Solar system, comets dominate the mass
budget of bodies that are ejected into interstellar space, since they form
further away and are less tightly bound. However 1I/`Oumuamua, the first
interstellar object detected, appears asteroidal in its spectra and in its lack
of detectable activity. We argue that the galactic budget of interstellar
objects like 1I/`Oumuamua should be dominated by planetesimal material ejected
during planet formation in circumbinary systems, rather than in single star
systems or widely separated binaries. We further show that in circumbinary
systems, rocky bodies should be ejected in comparable numbers to icy ones. This
suggests that a substantial fraction of additional interstellar objects
discovered in the future should display an active coma. We find that the rocky
population, of which 1I/`Oumuamua seems to be a member, should be predominantly
sourced from A-type and late B-star binaries.


  We demonstrate a novel comb tuning method for microresonator-based Kerr comb
generators. Continuously tunable, low-noise, and coherent comb generation is
achieved in a CMOS-compatible silicon nitride microring resonator.


  We study connections between orthogonal polynomials, reproducing kernel
functions, and polynomials $p$ minimizing Dirichlet-type norms
$\|pf-1\|_{\alpha}$ for a given function $f$. For $\alpha\in [0,1]$ (which
includes the Hardy and Dirichlet spaces of the disk) and general $f$, we show
that such extremal polynomials are non-vanishing in the closed unit disk. For
negative $\alpha$, the weighted Bergman space case, the extremal polynomials
are non-vanishing on a disk of strictly smaller radius, and zeros can move
inside the unit disk. We also explain how $\mathrm{dist}_{D_{\alpha}}(1,f\cdot
\mathcal{P}_n)$, where $\mathcal{P}_n$ is the space of polynomials of degree at
most $n$, can be expressed in terms of quantities associated with orthogonal
polynomials and kernels, and we discuss methods for computing the quantities in
question.


  Recent advances in the development of ultra-low loss silicon nitride
integrated photonic circuits have heralded a new generation of integrated
lasers capable of reaching fiber laser coherence. However, these devices
presently are based on self-injection locking of distributed feedback (DFB)
laser diodes, increasing both the cost and requiring tuning of laser setpoints
for their operation. In contrast, turn-key legacy laser systems use reflective
semiconductor optical amplifiers (RSOA). While this scheme has been utilized
for integrated photonics-based lasers, so far, no cost-effective RSOA-based
integrated lasers exist that are low noise and simultaneously feature fast,
mode-hop-free and linear frequency tuning as required for frequency modulated
continuous wave (FMCW) LiDAR or for laser locking in frequency metrology. Here
we overcome this challenge and demonstrate a RSOA-based, frequency agile
integrated laser, that can be tuned with high speed, with high linearity at low
power. This is achieved using monolithic integration of piezoelectrical
actuators on ultra-low loss silicon nitride photonic integrated circuits in a
Vernier filter-based laser scheme. The laser operates at 1550 nm, features 6 mW
output power, 400 Hz intrinsic laser linewidth, and allows ultrafast wavelength
switching within 7 ns rise time and 75 nW power consumption. In addition, we
demonstrate the suitability for FMCW LiDAR by showing laser frequency tuning
over 1.5 GHz at 100 kHz triangular chirp rate with nonlinearity of 0.25% after
linearization, and use the source for measuring a target scene 10 m away with a
8.5 cm distance resolution.


  A concrete realization of Enright's $T$ modules is obtained. This is used to
show their self-duality. As a consequence, the restricted duals of Verma
modules are also identified.


  We present the derivation, implementation, and analysis of a multiresolution
adaptive grid framework for numerical simulations on octree-based 3D
block-structured collocated grids with distributed computational architectures.
Our approach provides a consistent handling of non-lifted and lifted
interpolating wavelets of arbitrary order demonstrated using second, fourth,
and sixth order wavelets, combined with standard finite-difference based
discretization operators. We first validate that the wavelet family used
provides strict and explicit error control when coarsening the grid, and show
that lifting wavelets increase the grid compression rate while conserving
discrete moments across levels. Further, we demonstrate that high-order PDE
discretization schemes combined with sufficiently high order wavelets retain
the expected convergence order even at resolution jumps. We then simulate the
advection of a scalar to analyze convergence for the temporal evolution of a
PDE. The results shows that our wavelet-based refinement criterion is
successful at controlling the overall error while the coarsening criterion is
effective at retaining the relevant information on a compressed grid. Our
software exploits a block-structured grid data structure for efficient
multi-level operations, combined with a parallelization strategy that relies on
a one-sided MPI-RMA communication approach with active PSCW synchronization.
Using performance tests up to 16,384 cores, we demonstrate that this leads to a
highly scalable performance. The associated code is available under a BSD-3
license at https://github.com/vanreeslab/murphy.


  Space debris larger than 1 cm can damage space instruments and impact Earth.
The low-Earth orbits (at heights smaller than 2000 km) and orbits near the
geostationary- Earth orbit (at 35786 km height) are especially endangered,
because most satellites orbit at these latitudes. With current technology space
debris smaller than 10 cm cannot be tracked. Smaller space debris burn up and
evaporate in the atmosphere, but larger ones fall to the Earth's surface. For
practical reasons it would be important to know the mass, composition, shape,
velocity, direction of motion and impact time of space debris re-entering the
atmosphere and falling to Earth. Since it is very difficult to measure these
physical parameters, almost nothing is known about them. To partly fill this
gap, we performed computer modelling with which we studied the celestial
mechanics of spherical re-entry particles falling to Earth due to air drag.We
determined the time, velocity and angle of impact as functions of the launch
height, direction, speed and size of spherical re-entry particles. Our results
can also be used for semi-spherical meteoroid particles of the interplanetary
dust entering the Earth's atmosphere.


  Agricultural production is highly dependent on naturally occurring
environmental conditions like change of seasons and the weather. Especially in
fruit and wine growing, late frosts occurring shortly after the crops have
sprouted have the potential to cause massive damage to plants [L1,L2] [1]. In
this article we present a cost-efficient temperature monitoring system for
detecting and reacting to late frosts to prevent crop failures. The proposed
solution includes a data space where Internet of Things (IoT) devices can form
a cyber-physical system (CPS) to interact with their nearby environment and
securely exchange data. Based on this data, more accurate predictions can be
made in the future using machine learning (ML), which will further contribute
to minimising economic damage caused by crop failures.


  In this paper, we present a novel computational framework for portfolio-wide
risk management problems, where the presence of a potentially large number of
risk factors makes traditional numerical techniques ineffective. The new method
utilises a coupled system of BSDEs for the valuation adjustments (xVA) and
solves these by a recursive application of a neural network based BSDE solver.
This not only makes the computation of xVA for high-dimensional problems
feasible, but also produces hedge ratios and dynamic risk measures for xVA, and
allows simulations of the collateral account.


  We observe the almost edge-on (i $\sim$ 90 degrees) galaxy NGC 4302 using
ALMA (CO) and VLA (H I) to measure the gas disk thickness for investigating the
volumetric star formation law (SFL). The recent star formation rate (SFR) is
estimated based on a linear combination of IR 24 micron and H$\alpha$
emissions. The measured scale heights of CO and H I increase significantly with
radius. Using the scale heights along with the vertically integrated surface
densities, we derive the mid-plane volume densities of the gas ($\rho_{\rm
HI}$, $\rho_{\rm H_2}$, and $\rho_{\rm gas}$ = $\rho_{\rm HI}$+$\rho_{\rm
H_2}$) and the SFR ($\rho_{\rm SFR}$) and compare the volumetric SFL
($\rho_{\rm SFR} \propto \rho_{\rm gas}^n$) with the vertically integrated SFL
($\Sigma_{\rm SFR} \propto \Sigma_{\rm gas}^N$). We find tight power-law
correlations between the SFR and the gas (H I, H$_2$, and the total gas) in
both volume and surface densities. The power-law indices of the total gas and H
I for the volumetric SFL are noticeably smaller than the indices for the
vertically integrated SFL while the H$_2$ indices for both cases are similar to
each other. In terms of the star formation efficiency (SFE), we find that the
molecular and total gas SFEs are roughly constant, while the atomic SFE is
clearly decreasing with radius in both cases.


  To deploy deep learning algorithms on resource-limited scenarios, an emerging
device-resistive random access memory (ReRAM) has been regarded as promising
via analog computing. However, the practicability of ReRAM is primarily limited
due to the weight drifting of ReRAM neural networks due to multi-factor
reasons, including manufacturing, thermal noises, and etc. In this paper, we
propose a novel Bayesian optimization method for fault tolerant neural network
architecture (BayesFT). For neural architecture search space design, instead of
conducting neural architecture search on the whole feasible neural architecture
search space, we first systematically explore the weight drifting tolerance of
different neural network components, such as dropout, normalization, number of
layers, and activation functions in which dropout is found to be able to
improve the neural network robustness to weight drifting. Based on our
analysis, we propose an efficient search space by only searching for dropout
rates for each layer. Then, we use Bayesian optimization to search for the
optimal neural architecture robust to weight drifting. Empirical experiments
demonstrate that our algorithmic framework has outperformed the
state-of-the-art methods by up to 10 times on various tasks, such as image
classification and object detection.


  I present the next-to-next-to-leading-logarithm (NNLL) resummation of soft
and collinear gluon corrections to single top quark production in the s
channel. Attaining NNLL accuracy involves the calculation of the two-loop soft
anomalous dimension for the partonic subprocesses. Finite-order expansions of
the resummed cross section are calculated through next-to-next-to-leading order
(NNLO). Numerical results are presented for s-channel single top quark
production at the Tevatron and the LHC, including the dependence of the cross
sections on the top quark mass and the uncertainties in the theoretical
prediction. The higher-order corrections are significant for energies at both
colliders and they decrease the theoretical uncertainty.


  We find the gravity solution corresponding to a large number of NS or D
fivebranes wrapped on a two sphere so that we have pure ${\cal N}=1$ super
Yang-Mills in the IR. The supergravity solution is smooth, it shows confinement
and it breaks the $U(1)_R$ chiral symmetry in the appropriate way. When the
gravity approximation is valid the masses of glueballs are comparable to the
masses of Kaluza Klein states on the fivebrane, but if we could quantize
strings on this background it looks like we should be able to decouple the KK
states.


  A simple construction of quaternary hermitian self-orthogonal codes with
parameters $[2n+1,k+1]$ and $[2n+2,k+2]$ from a given pair of self-orthogonal
$[n,k]$ codes, and its link to quantum codes is considered. As an application,
an optimal quaternary linear $[28,20,6]$ dual containing code is found that
yields a new optimal $[[28,12,6]]$ quantum code.


  This article develops analysis on fractal $3N$-gaskets, a class of
post-critically finite fractals which include the Sierpinski triangle for
$N=1$, specifically properties of the Laplacian $\Delta$ on these gaskets. We
first prove the existence of a self-similar geodesic metric on these gaskets,
and prove heat kernel estimates for this Laplacian with respect to the geodesic
metric. We also compute the elements of the method of spectral decimation, a
technique used to determine the spectrum of post-critically finite fractals.
Spectral decimation on these gaskets arises from more complicated dynamics than
in previous examples, i.e. the functions involved are rational rather than
polynomial. Due to the nature of these dynamics, we are able to show that there
are gaps in the spectrum.


  Laser diodes based on solution-processable materials could benefit numerous
technologies including integrated electronics and photonics, telecommunication,
and medical diagnostics. An attractive system for implementing these devices is
colloidal semiconductor quantum dots (QDs). The primary challenge that hampered
progress towards a QD laser diode (QLD) has been fast nonradiative Auger decay
of optical-gain-active multicarrier states. Recently, this problem has been
resolved by employing continuously graded QDs (cg-QDs) wherein Auger
recombination is strongly suppressed. The use of these structures allowed for
demonstrations of optical gain with electrical pumping and optically-excited
lasing in multilayered LED-like devices. Here we report on achieving the next
critical milestone towards a QLD, which is the demonstration of optically
excited amplified spontaneous emission from a fully functional high-current
density electroluminescent device. This advance has become possible due to
excellent optical gain properties of novel 'compact' cg-QDs and a new LED
architecture, which allows for concerted optimization of its optical and
electrical properties. The results of this work strongly suggest the
feasibility of the final step towards a functional QLD, which is the
demonstration of lasing with electrical pumping.


  In this sequence of papers, noncommutative analysis is used to give a
consistent axiomatic approach to a unified conceptual foundation of classical
and quantum physics.
  The present Part I defines the concepts of observables, states and ensembles,
clarifies the logical relations and operations for them, and shows how they
give rise to dynamics and probabilities.
  States are identified with maximal consistent sets of weak equalities in the
algebra of observables (instead of, as usual, with the rays in a Hilbert
space). This leads to a concise foundation of quantum mechanics, free of
undefined terms, separating in a clear way the deterministic and the stochastic
features of quantum physics.
  The traditional postulates of quantum mechanics are derived from
well-motivated axiomatic assumptions. No special quantum logic is needed to
handle the peculiarities of quantum mechanics. Foundational problems associated
with the measurement process, such as the reduction of the state vector,
disappear.
  The new interpretation of quantum mechanics contains `elements of physical
reality' without the need to introduce a classical framework with hidden
variables. In particular, one may talk about the state of the universe without
the need of an external observer and without the need to assume the existence
of multiple universes.


  We consider the use of Bayesian information criteria for selection of the
graph underlying an Ising model. In an Ising model, the full conditional
distributions of each variable form logistic regression models, and variable
selection techniques for regression allow one to identify the neighborhood of
each node and, thus, the entire graph. We prove high-dimensional consistency
results for this pseudo-likelihood approach to graph selection when using
Bayesian information criteria for the variable selection problems in the
logistic regressions. The results pertain to scenarios of sparsity and
following related prior work the information criteria we consider incorporate
an explicit prior that encourages sparsity.


  We analyze correlations between pairs of particle detectors quadratically
coupled to a real scalar field. We find that, while a single quadratically
coupled detector presents no divergences, when one considers pairs of detectors
there emerge unanticipated persistent divergences (not regularizable via smooth
switching or smearing) in the entanglement they acquire from the field. We have
characterized such divergences, discussed whether a suitable regularization can
allow for fair comparison of the entanglement harvesting ability of the
quadratic and the linear couplings, and finally we have found a UV-safe
quantifier of harvested correlations. Our results are relevant to future
studies of the entanglement structure of the fermionic vacuum.


  Evaluation of biases in language models is often limited to synthetically
generated datasets. This dependence traces back to the need for a prompt-style
dataset to trigger specific behaviors of language models. In this paper, we
address this gap by creating a prompt dataset with respect to occupations
collected from real-world natural sentences present in Wikipedia. We aim to
understand the differences between using template-based prompts and natural
sentence prompts when studying gender-occupation biases in language models. We
find bias evaluations are very sensitive to the design choices of template
prompts, and we propose using natural sentence prompts for systematic
evaluations to step away from design choices that could introduce bias in the
observations.


  At IPEC 2020, Bergougnoux, Bonnet, Brettell, and Kwon showed that a number of
problems related to the classic Feedback Vertex Set (FVS) problem do not admit
a $2^{o(k \log k)} \cdot n^{\mathcal{O}(1)}$-time algorithm on graphs of
treewidth at most $k$, assuming the Exponential Time Hypothesis. This contrasts
with the $3^{k} \cdot k^{\mathcal{O}(1)} \cdot n$-time algorithm for FVS using
the Cut&Count technique.
  During their live talk at IPEC 2020, Bergougnoux et al.~posed a number of
open questions, which we answer in this work.
  - Subset Even Cycle Transversal, Subset Odd Cycle Transversal, Subset
Feedback Vertex Set can be solved in time $2^{\mathcal{O}(k \log k)} \cdot n$
in graphs of treewidth at most $k$. This matches a lower bound for Even Cycle
Transversal of Bergougnoux et al.~and improves the polynomial factor in some of
their upper bounds.
  - Subset Feedback Vertex Set and Node Multiway Cut can be solved in time
$2^{\mathcal{O}(k \log k)} \cdot n$, if the input graph is given as a
clique-width expression of size $n$ and width $k$.
  - Odd Cycle Transversal can be solved in time $4^k \cdot k^{\mathcal{O}(1)}
\cdot n$ if the input graph is given as a clique-width expression of size $n$
and width $k$. Furthermore, the existence of a constant $\varepsilon > 0$ and
an algorithm performing this task in time $(4-\varepsilon)^k \cdot
n^{\mathcal{O}(1)}$ would contradict the Strong Exponential Time Hypothesis.


  We propose Marve, a system for extracting measurement values, units, and
related words from natural language text. Marve uses conditional random fields
(CRF) to identify measurement values and units, followed by a rule-based system
to find related entities, descriptors and modifiers within a sentence. Sentence
tokens are represented by an undirected graphical model, and rules are based on
part-of-speech and word dependency patterns connecting values and units to
contextual words. Marve is unique in its focus on measurement context and early
experimentation demonstrates Marve's ability to generate high-precision
extractions with strong recall. We also discuss Marve's role in refining
measurement requirements for NASA's proposed HyspIRI mission, a hyperspectral
infrared imaging satellite that will study the world's ecosystems. In general,
our work with HyspIRI demonstrates the value of semantic measurement
extractions in characterizing quantitative discussion contained in large
corpuses of natural language text. These extractions accelerate broad,
cross-cutting research and expose scientists new algorithmic approaches and
experimental nuances. They also facilitate identification of scientific
opportunities enabled by HyspIRI leading to more efficient scientific
investment and research.


  We present results on two related topics: 1. A discussion of high redshift
candidates (z>4.5), and 2. A study of very small galaxies at intermediate
redshifts, both sets being detected in the region of the northern Hubble Deep
Field covered by deep NICMOS observations at 1.6 and 1.1 microns. The high
redshift candidates are just those with redshift z>4.5 as given in the recent
catalog of Thompson, Weymann and Storrie-Lombardi, while the ``small galaxy''
sample is defined to be those objects with isophotal area <= 0.2 squ. arcsec
and with photometric redshifts 1<z<4.5. Of the 19 possible high redshift
candidates listed in the Thompson et al. catalog, 11 have (nominal) photometric
redshifts less than 5.0. Of these, however, only 4 are ``robust'' in the sense
of yielding high redshifts when the fluxes are randomly perturbed with errors
comparable to the estimated measuring error in each wave band. For the 8 other
objects with nominal photometric redshifts greater than 5.0, one (WFPC2 4--473)
has a published spectroscopic redshift. Of the remaining 7, 4 are robust in the
sense indicated above. Two of these form a close pair (NIC 586 and NIC 107).
The redshift of the object having formally the highest redshift, at 6.56
(NIC118 = WFPC2 4--601), is problematic, since F606W and F814W flux are clearly
present, and the nature of this object poses a dilemma. (abridged)


  It is argued that high energy density excitations, responsible for UV
divergences in quantum field theories, including quantum gravity, are likely to
be the source of child universes which carry them out of the original space
time. This decoupling prevents these high UV excitations from having any
influence on physical amplitudes. Child universe production could therefore be
responsible for UV regularization in quantum field theories which takes into
account gravitational effects. Also child universe production in the last
stages of black hole evaporation, the prediction of absence of tranplanckian
primordial perturbations, connection to the minimum length hypothesis and in
particular connection to the maximal curvature hypothesis are discussed.


  In a recent Letter Ciftci and Cakmak [EPL 87, 60003 (2009)] showed that the
two dimensional random walk in a bounded domain, where walkers which cross the
boundary return to a base curve near origin with deterministic rules, can
produce regular patterns. Our numerical calculations suggest that the
cumulative probability distribution function of the returning walkers along the
base curve is a Devil's staircase, which can be explained from the mapping of
these walks to a non-linear stochastic map. The non-trivial probability
distribution function(PDF) is a universal feature of CCRW characterized by the
fractal dimension d=1.75(0) of the PDF bounding curve.


  Let $X$ be a smooth projective variety. We construct partial Okounkov bodies
associated to Hermitian pseudo-effective line bundles $(L,\phi)$ on $X$. We
show that partial Okounkov bodies are universal invariants of the singularity
of $\phi$. As an application, we generalize the theorem of Boucksom--Chen and
construct Duistermaat--Heckman measures associated with finite energy metrics
on the Berkovich analytification of an ample line bundle.


  An Earth orbiting detector sensitive to gamma ray photons will see step-like
occultation features in its counting rate when a gamma ray point source crosses
the Earth's limb. This is due to the change in atmospheric attenuation of the
gamma rays along the line of sight. In an uncollimated detector, these
occultation features can be used to locate and monitor astrophysical sources
provided their signals can be individually separated from the detector
background. We show that the Earth occultation technique applied to the Burst
and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory
(CGRO) is a viable and flexible all-sky monitor in the low energy gamma ray and
hard X-ray energy range (20 keV - 1 MeV). The method is an alternative to more
sophisticated photon imaging devices for astronomy, and can serve well as a
cost-effective science capability for monitoring the high energy sky.
  Here we describe the Earth occultation technique for locating new sources and
for measuring source intensity and spectra without the use of complex
background models. Examples of transform imaging, step searches, spectra, and
light curves are presented. Systematic uncertainties due to source confusion,
detector response, and contamination from rapid background fluctuations are
discussed and analyzed for their effect on intensity measurements. A sky
location-dependent average systematic error is derived as a function of
galactic coordinates. The sensitivity of the technique is derived as a function
of incident photon energy and also as a function of angle between the source
and the normal to the detector entrance window. Occultations of the Crab Nebula
by the Moon are used to calibrate Earth occultation flux measurements
independent of possible atmospheric scattering effects.


  We consider move-making algorithms for energy minimization of multi-label
Markov Random Fields (MRFs). Since this is not a tractable problem in general,
a commonly used heuristic is to minimize over subsets of labels and variables
in an iterative procedure. Such methods include {\alpha}-expansion,
{\alpha}{\beta}-swap, and range-moves. In each iteration, a small subset of
variables are active in the optimization, which diminishes their effectiveness,
and increases the required number of iterations. In this paper, we present a
method in which optimization can be carried out over all labels, and most, or
all variables at once. Experiments show substantial improvement with respect to
previous move-making algorithms.


  In this paper, four sets of evolutionary models are computed with different
values of the mixing length parameter $\alpha_{\rm p}$ and the overshooting
parameter $\delta_{\rm ov}$. The properties of the convective cores and the
convective envelopes are studied in the massive stars. We get three
conclusions: First, the larger $\alpha_{\rm p}$ leads to enhancing the
convective mixing, removing the chemical gradient, and increasing the
convective heat transfer efficiency. Second, core potential $\phi_{\rm c} =
M_{\rm c} / R_{\rm c}$ describes sufficiently the evolution of a star, whether
it is a red or blue supergiant at central helium ignition. Third, the
discontinuity of hydrogen profile above the hydrogen burning shell seriously
affect the occurrence of blue loops in the Hertzsprung--Russell diagram.


  The discovery of quantum Hall effect in two-dimensional (2D) electronic
systems inspired the topological classifications of electronic systems1,2. By
stacking 2D quantum Hall effects with interlayer coupling much weaker than the
Landau level spacing, quasi-2D quantum Hall effects have been experimentally
observed3~7, due to the similar physical origin of the 2D counterpart.
Recently, in a real 3D electronic gas system where the interlayer coupling is
much stronger than the Landau level spacing, 3D quantum Hall effect has been
observed in ZrTe58. In this Letter, we report the electronic transport features
of its sister bulk material, i.e., HfTe5, under external magnetic field. We
observe a series of plateaus in Hall resistance \r{ho}xy as magnetic field
increases until it reaches the quantum limit at 1~2 Tesla. At the plateau
regions, the longitudinal resistance \r{ho}xx exhibits local minima. Although
\r{ho}xx is still nonzero, its value becomes much smaller than \r{ho}xy at the
last few plateaus. By mapping the Fermi surface via measuring the Shubonikov-de
Haas oscillation, we find that the strength of Hall plateau is proportional to
the Fermi wavelength, suggesting that its formation may be attributed to the
gap opening from the interaction driven Fermi surface instability. By comparing
the bulk band structures of ZrTe5 and HfTe5, we find that there exists an extra
pocket near the Fermi level of HfTe5, which may lead to the finite but nonzero
longitudinal conductance.


  Automatic Speech Recognition (ASR) using multiple microphone arrays has
achieved great success in the far-field robustness. Taking advantage of all the
information that each array shares and contributes is crucial in this task.
Motivated by the advances of joint Connectionist Temporal Classification
(CTC)/attention mechanism in the End-to-End (E2E) ASR, a stream attention-based
multi-array framework is proposed in this work. Microphone arrays, acting as
information streams, are activated by separate encoders and decoded under the
instruction of both CTC and attention networks. In terms of attention, a
hierarchical structure is adopted. On top of the regular attention networks,
stream attention is introduced to steer the decoder toward the most informative
encoders. Experiments have been conducted on AMI and DIRHA multi-array corpora
using the encoder-decoder architecture. Compared with the best single-array
results, the proposed framework has achieved relative Word Error Rates (WERs)
reduction of 3.7% and 9.7% in the two datasets, respectively, which is better
than conventional strategies as well.


  Synthesizing medical images while preserving their structural information is
crucial in medical research. In such scenarios, the preservation of anatomical
content becomes especially important. Although recent advances have been made
by incorporating instance-level information to guide translation, these methods
overlook the spatial coherence of structural-level representation and the
anatomical invariance of content during translation. To address these issues,
we introduce hierarchical granularity discrimination, which exploits various
levels of semantic information present in medical images. Our strategy utilizes
three levels of discrimination granularity: pixel-level discrimination using a
Brain Memory Bank, structure-level discrimination on each brain structure with
a re-weighting strategy to focus on hard samples, and global-level
discrimination to ensure anatomical consistency during translation. The image
translation performance of our strategy has been evaluated on three independent
datasets (UK Biobank, IXI, and BraTS 2018), and it has outperformed
state-of-the-art algorithms. Particularly, our model excels not only in
synthesizing normal structures but also in handling abnormal (pathological)
structures, such as brain tumors, despite the variations in contrast observed
across different imaging modalities due to their pathological characteristics.
The diagnostic value of synthesized MR images containing brain tumors has been
evaluated by radiologists. This indicates that our model may offer an
alternative solution in scenarios where specific MR modalities of patients are
unavailable. Extensive experiments further demonstrate the versatility of our
method, providing unique insights into medical image translation.


  We report the first observed outburst of the magnetic cataclysmic variable XY
Ari. X-ray observations show a flux increase by an order of magnitude the day
after the first signs of outburst. During the 5-d duration the X-ray spin pulse
is greatly enhanced and the X-ray spectrum far more absorbed. We suggest that
the inner disc pushes inwards during outburst, blocking the view to the lower
accreting pole, breaking the symmetry present in quiescence, and so producing a
large pulsation. The observations are consistent with a disc instability as the
cause of the outburst, although we can't rule out alternatives. We draw
parallels between our data and the UV delay and dwarf nova oscillations seen in
non-magnetic dwarf novae.


  While Indices, Index tracking funds and ETFs have grown in popularity during
then last ten years, there are many structural problems inherent in Index
calculation methodologies and the legal/economic structure of ETFs. These
problems raise actionable issues of Suitability and fraud under US securities
laws, because most Indices and ETFs are misleading, have substantial tracking
errors and dont reflect what they are supposed to track. This article
contributes to the existing literature by: a) introducing and characterizing
the errors and Biases inherent in risk-adjusted index weighting methods and the
associated adverse effects; b) showing how these biases/effects inherent in
Index calculation methods reduce social welfare, and can form the basis for
harmful arbitrage activities.


  We address the problem of text-guided video temporal grounding, which aims to
identify the time interval of a certain event based on a natural language
description. Different from most existing methods that only consider RGB images
as visual features, we propose a multi-modal framework to extract complementary
information from videos. Specifically, we adopt RGB images for appearance,
optical flow for motion, and depth maps for image structure. While RGB images
provide abundant visual cues of certain events, the performance may be affected
by background clutters. Therefore, we use optical flow to focus on large motion
and depth maps to infer the scene configuration when the action is related to
objects recognizable with their shapes. To integrate the three modalities more
effectively and enable inter-modal learning, we design a dynamic fusion scheme
with transformers to model the interactions between modalities. Furthermore, we
apply intra-modal self-supervised learning to enhance feature representations
across videos for each modality, which also facilitates multi-modal learning.
We conduct extensive experiments on the Charades-STA and ActivityNet Captions
datasets, and show that the proposed method performs favorably against
state-of-the-art approaches.


  Given a Muckenhoupt weight $w$ and a second order divergence form elliptic
operator $L$, we consider different versions of the weighted Hardy space
$H^1_L(w)$ defined by conical square functions and non-tangential maximal
functions associated with the heat and Poisson semigroups generated by $L$. We
show that all of them are isomorphic and also that $H^1_L(w)$ admits a
molecular characterization. One of the advantages of our methods is that our
assumptions extend naturally the unweighted theory developed by S. Hofmann and
S. Mayboroda and we can immediately recover the unweighted case. Some of our
tools consist in establishing weighted norm inequalities for the non-tangential
maximal functions, as well as comparing them with some conical square functions
in weighted Lebesgue spaces.


  Ga$_{0.51}$In$_{0.49}$P is a promising candidate for thermally tunable
nanophotonic devices due to its low thermal conductivity. In this work we study
its thermo-optical response. We obtain the linear thermo-optical coefficient
$dn/dT=2.0\pm0.3\cdot 10^{-4}\,\rm{K}^{-1}$ by investigating the transmission
properties of a single mode-gap photonic crystal nanocavity.


  We investigate the algebraic properties of the quantum counterpart of the
classical canonical transformations using the symbol-calculus approach to
quantum mechanics. In this framework we construct a set of pseudo-differential
operators which act on the symbols of operators, i.e., on functions defined
over phase-space. They act as operatorial left- and right- multiplication and
form a $W_{\infty}\times W_{\infty}$- algebra which contracts to its diagonal
subalgebra in the classical limit. We also describe the Gel'fand-Naimark-Segal
(GNS) construction in this language and show that the GNS representation-space
(a doubled Hilbert space) is closely related to the algebra of functions over
phase-space equipped with the star-product of the symbol-calculus.


  A theory of photoinduced directed bending of non-crystalline molecular films
is presented. Our approach is based on elastic deformation of the film due to
interaction between molecules ordered through polarized light irradiation. The
shape of illuminated film is obtained in the frame of the nonlinear elasticity
theory. It is shown that the shape and the curvature of the film depend on the
polarization and intensity of the light. The curvature of an irradiated film is
a non-monotonic function of the extinction coefficient.


  Sequential Multiple-Assignment Randomized Trials (SMARTs) play an
increasingly important role in psychological and behavioral health research.
This experimental approach enables researchers to answer scientific questions
about how to sequence and match interventions to the unique, changing needs of
individuals. A variety of sample size planning resources for SMART studies have
been developed in recent years; these enable researchers to plan SMARTs for
addressing different types of scientific questions. However, relatively limited
attention has been given to planning SMARTs with binary (dichotomous) outcomes,
which often require higher sample sizes relative to continuous outcomes.
Existing resources for estimating sample size requirements for SMARTs with
binary outcomes do not consider the potential to improve power by including a
baseline measurement and/or multiple repeated outcome measurements. The current
paper addresses this issue by providing sample size simulation code and
approximate formulas for two-wave repeated measures binary outcomes (i.e., two
measurement times for the outcome variable, before and after receiving the
intervention). The simulation results agree well with the formulas. We also
discuss how to use simulations to calculate power for studies with more than
two outcome measurement occasions. The results show that having at least one
repeated measurement of the outcome can substantially improve power under
certain conditions.


  The recent discovery and resummation of a class of single-logarithmic effects
(non-global logs), has a significant impact on several QCD observables ranging
from the classic Sterman-Weinberg jet definition to currently studied event
shapes and rapidity gap observables. The discovery of the above effects
overturns, for example, the common wisdom that hadronic energy flow in limited
interjet regions is dictated primarily by the colour flow in the underlying
hard partonic subprocess. We discuss some features of non-global logs and the
rapid progress being made in estimating and controlling such corrections.


  In 1956 Marguerite Frank and Paul Wolfe proved that a quadratic function
which is bounded below on a polyhedron $P$ attains its infimum on $P$. In this
work we search for larger classes of sets $F$ with this Frank-and-Wolfe
property. We establish the existence of non-polyhedral Frank-and-Wolfe sets,
obtain internal characterizations by way of asymptotic properties, and
investigate stability of the Frank-and-Wolfe class under various operations.


  We establish the Hopf boundary point lemma for the Schr\"odinger operator
$-\Delta + V$ involving potentials $V$ that merely belong to the space
$L^{1}_{loc}(\Omega)$. More precisely, we prove that among all supersolutions
$u$ of $-\Delta + V$ which vanish on the boundary $\partial\Omega$ and are such
that $V u \in L^{1}(\Omega)$, if there exists one supersolution which satisfies
$\partial u/\partial n < 0$ almost everywhere on $\partial\Omega$ with respect
to the outward unit vector $n$, then such a property holds for every nontrivial
supersolution in the same class. We rely on the existence of nontrivial
solutions of the nonhomogeneous Dirichlet problem with boundary datum in
$L^{\infty}(\partial\Omega)$.


  This paper and its prequel ("Part I") prove a generalization of the usual
gluing theorem for two index 1 pseudoholomorphic curves U_+ and U_- in the
symplectization of a contact 3-manifold. We assume that for each embedded Reeb
orbit gamma, the total multiplicity of the negative ends of U_+ at covers of
gamma agrees with the total multiplicity of the positive ends of U_- at covers
of gamma. However, unlike in the usual gluing story, here the individual
multiplicities are allowed to differ. In this situation, one can often glue U_+
and U_- to an index 2 curve by inserting genus zero branched covers of
R-invariant cylinders between them. This paper shows that the signed count of
such gluings equals a signed count of zeroes of a certain section of an
obstruction bundle over the moduli space of branched covers of the cylinder.
Part I obtained a combinatorial formula for the latter count and, assuming the
result of the present paper, deduced that the differential d in embedded
contact homology satisfies d^2=0. The present paper completes all of the
analysis that was needed in Part I. The gluing technique explained here is in
principle applicable to more gluing problems. We also prove some lemmas
concerning the generic behavior of pseudoholomorphic curves in
symplectizations, which may be of independent interest.


  Spatial interaction effects between charge carriers in ionic systems play a
sizable role beyond a classical Maxwellian description. We develop a nonlocal,
two-fluid, hydrodynamic theory of charges and study ionic plasmon effects, i.
e. collective charge oscillations in electrolytes. Ionic spatial dispersion
arises from both positive and negative charge dynamics with an impact in the
(far-)infrared. Despite highly classical parameters, nonlocal quenching of up
to 90% is observed for particle sizes spanning orders of magnitude. Notably,
the ionic system is widely tunable via ion concentration, mass and charge, in
contrast to solid metal nanoparticles. A nonlocal soft plasmonic theory for
ions is relevant for biological and chemical systems bridging hard and soft
matter theory and allowing the investigation of non-classical effects in
electrolytes in full analogy to solid metal particles. The presented
semi-classical approach allows studying plasmonic photo-catalysis introducing
nonlocal aspects into electrolyte-metal interactions.


  Let $M$ be a non-zero finitely generated module over a finite dimensional
commutative Noetherian local ring $(R,\mathfrak{m})$ with dim$_R(M)=t$. Let $I$
be an ideal of $R$ with grade$(I,M)=c$. In this article we will investigate
several natural homomorphisms of local cohomology modules. The main purpose of
this article is to investigate that the natural homomorphisms
Tor$^R_c(k,H^c_I(M))\to k\otimes_R M$ and Ext$^{d}_R(k,H^c_I(M))\to {\rm
Ext}^t_R(k, M)$ are non-zero where $d:=t-c$. In fact for a Cohen-Macaulay
module $M$ we will show that the homomorphism Ext$^d_R(k,H^c_I(M))\to {\rm
Ext}^t_R(k, M)$ is injective (resp. surjective) if and only if the homomorphism
$H^{d}_{\mathfrak{m}}(H^c_{I}(M))\to H^t_{\mathfrak{m}}(M)$ is injective (resp.
surjective) under the additional assumption of vanishing of Ext modules. The
similar results are obtained for the homomorphism Tor$^R_c(k,H^c_I(M))\to
k\otimes_R M$. Moreover we will construct the natural homomorphism ${\rm
Tor}^R_c(k, H^c_I(M))\to {\rm Tor}^R_c(k, H^c_J(M))$ for the ideals $J\subseteq
I$ with $c = {\rm grade}(I,M)= {\rm grade}(J,M)$. There are several sufficient
conditions on $I$ and $J$ to prove this homomorphism is an isomorphism.


  We show that the class of inductive limits of the representations of finite
symmetric groups with simple spectrum coinsides with the class of Markov
representations of the infinite symmetric group associated with Markov measures
on the space of infinite Young tableaux.
  We also show that the representations of infinite symmetric group induced
from identity representation of two-block Young subgroup are Markov
representations and find explicit formulas for transition probabilities of
corresponding Markov measure on the Young diagrmas.
  Induced two-row representations of finite symmetric group are studied using
tensor model of those representations which alows easily to obtain the formulas
for Gel'fand-Zetlin basis.


  By means of quantum Monte Carlo simulations, combined with a stochastic
analytic continuation, we examine the spin dynamics of the spin-1/2 planar (XY)
ferromagnet on the kagome lattice with additional four-site ring exchange
terms. Such exchange processes were previously considered to lead into an
extended $Z_2$ quantum spin liquid phase beyond a quantum critical point from
the XY-ferromagnet. We examine the dynamical spin structure factor in the
non-magnetic regime and probe for signatures of spin fractionalization.
Furthermore, we contrast our findings and the corresponding energy scales of
the excitation gaps in the ring exchange model to those emerging in a related
Balents-Fisher-Girvin model with a $Z_2$ quantum spin liquid phase, and monitor
the softening of the magnon mode upon approaching the quantum critical point
from the XY-ferromagnetic regime.


  We study gravothermal evolution of dark matter halos in the presence of
differential self-scattering that has strong velocity and angular dependencies.
We design controlled N-body simulations to model Rutherford and Moller
scatterings in the halo, and follow its evolution in both core-expansion and
-collapse phases. The simulations show the commonly-used transfer cross section
underestimates the effects of dark matter self-interactions, but the viscosity
cross section provides an accurate approximation for modeling angular-dependent
dark matter scattering. We investigate thermodynamic properties of the halo,
and find that the three moments of the Boltzmann equation under the fluid
approximation are satisfied. We further propose a constant effective cross
section, which integrates over the halo's characteristic velocity dispersion
with weighting kernels motivated by kinetic theory of heat conduction. The
effective cross section provides a good approximation to differential
self-scattering for most of the halo evolution. It indicates that we can map
astrophysical constraints on a constant self-interacting cross section to an
SIDM model with velocity- and angular-dependent scatterings.


  The workshop `Astrophysical Dynamics 1999/2000' followed a homonymous
advanced research course, and both activities were organized by me. In this
opening paper of the proceedings book, I describe them and document their
strong impact on the academic life of the local institutions. The advanced
research course was open to graduate students, senior researchers, and
motivated under-graduate students with good background in physics and
mathematics. The course covered several multi-disciplinary issues of modern
research on astrophysical dynamics, and thus also of interest to physicists,
mathematicians and engineers. The major topic was gas dynamics, viewed in
context with stellar dynamics and plasma physics. The course was complemented
by parallel seminars on hot topics given by experts in such fields, and open to
a wide scientific audience. In particular, I gave a friendly introduction to
wavelets, which are becoming an increasingly powerful tool not only for
processing signals and images but also for analysing fractals and turbulence,
and which promise to have important applications to dynamical modelling of disc
galaxies. The workshop was open to a wide scientific audience. The workshop
with published proceedings book was, as a matter of fact, the innovative form
of exam that I proposed for the advanced research course. The contributions
were refereed and their quality is high on average, exceptionally high in a few
cases. The advanced research course and the workshop all together produced
great enthusiasm in the students and welcomed the participation of a hundred
different people, which means an order of magnitude more than an average
graduate course at Chalmers University of Technology and G\"oteborg University.


  We explore the effects of Coulomb interaction upon the nuclear liquid vapor
phase transition. Because large nuclei (A>60) are metastable objects, phases,
phase coexistence, and phase transitions cannot be defined with any generality
and the analogy to liquid vapor is ill-posed for these heavy systems. However,
it is possible to account for the Coulomb interaction in the decay rates and
obtain the coexistence phase diagram for the corresponding uncharged system.


  This paper provides a new model to compute the fractal dimension of a subset
on a generalized-fractal space. Recall that fractal structures are a perfect
place where a new definition of fractal dimension can be given, so we perform a
suitable discretization of the Hausdorff theory of fractal dimension. We also
find some connections between our definition and the classical ones and also
with fractal dimensions I & II (see http://arxiv.org/submit/0080421/pdf).
Therefore, we generalize them and obtain an easy method in order to calculate
the fractal dimension of strict self-similar sets which are not required to
verify the open set condition.


  Recent work has established clear links between the generalization
performance of trained neural networks and the geometry of their loss landscape
near the local minima to which they converge. This suggests that qualitative
and quantitative examination of the loss landscape geometry could yield
insights about neural network generalization performance during training. To
this end, researchers have proposed visualizing the loss landscape through the
use of simple dimensionality reduction techniques. However, such visualization
methods have been limited by their linear nature and only capture features in
one or two dimensions, thus restricting sampling of the loss landscape to lines
or planes. Here, we expand and improve upon these in three ways. First, we
present a novel "jump and retrain" procedure for sampling relevant portions of
the loss landscape. We show that the resulting sampled data holds more
meaningful information about the network's ability to generalize. Next, we show
that non-linear dimensionality reduction of the jump and retrain trajectories
via PHATE, a trajectory and manifold-preserving method, allows us to visualize
differences between networks that are generalizing well vs poorly. Finally, we
combine PHATE trajectories with a computational homology characterization to
quantify trajectory differences.


  We investigate how the criticality of the quantum Hall plateau transition in
disordered graphene differs from those in the ordinary quantum Hall systems,
based on the honeycomb lattice with ripples modeled as random hoppings. The
criticality of the graphene-specific n=0 Landau level is found to change
dramatically to an anomalous, almost exact fixed point as soon as we make the
random hopping spatially correlated over a few bond lengths. We attribute this
to the preserved chiral symmetry and suppressed scattering between K and K'
points in the Brillouin zone. The results suggest that a fixed point for random
Dirac fermions with chiral symmetry can be realized in free-standing, clean
graphene with ripples.


  Four dense cores, L1582A, L1689A, B133 and B68, classified as prestellar in
terms of the absence of detectable NIR emission, are observed at radio
wavelengths to investigate whether they nurture very young protostars. No
definite young protostars were discovered in any of the four cores observed. A
few radio sources were discovered close to the observed cores, but these are
most likely extragalactic sources or YSOs unrelated to the cores observed. In
L1582A we discovered a weak radio source near the centre of the core with radio
characteristics and offset from the peak of the submillimeter emission similar
to that of the newly discovered protostar in the core L1014, indicating a
possible protostellar nature for this source. This needs to be confirmed with
near- and/or mid-infrared observations (e.g. with Spitzer). Hence based on the
current observations we are unable to confirm unequivocally that L1582A is
starless. In L1689A a possible 4.5-sigma radio source was discovered at the
centre of the core, but needs to be confirmed with future observations. In B133
a weak radio source, possibly a protostar, was discovered at the edge of the
core on a local peak of the core submm emission, but no source was detected at
the centre of the core. Thus, B133 is probably starless, but may have a
protostar at its edge. In B68 no radio sources were discovered inside or at the
edge of the core, and thus B68 is indeed starless. Four more radio sources with
spectral indices characteristic of young protostars were discovered outside the
cores but within the extended clouds in which these cores reside. Conclusions:
We conclude that the number of cores misclassified as prestellar is probably
very small and does not significantly alter the estimated lifetime of the
prestellar phase.


  A finite set X in the d-dimensional Euclidean space is called an s-distance
set if the set of Euclidean distances between any two distinct points of X has
size s. Larman--Rogers--Seidel proved that if the cardinality of a two-distance
set is greater than 2d+3, then there exists an integer k such that
a^2/b^2=(k-1)/k, where a and b are the distances. In this paper, we give an
extension of this theorem for any s. Namely, if the size of an s-distance set
is greater than some value depending on d and s, then certain functions of s
distances become integers. Moreover, we prove that if the size of X is greater
than the value, then the number of s-distance sets is finite.


  Current-voltage ($I$-$V$) characteristics of Tl$_2$Ba$_2$CaCu$_2$O$_8$ thin
films in zero magnetic field are measured and analyzed with the conventional
Kosterlitz-Thouless-Berezinskii (KTB) approach, dynamic scaling approach and
finite-size scaling approach, respectively. It is found from these results that
the $I$-$V$ relation is determined by the vortex-unbinding mechanism with the
KTB dynamic critical exponent $z=2$. On the other hand, the evidence of
finite-size effect is also found, which blurs the feature of a phase
transition.


  We present the results of a long-term monitoring campaign of the H\alpha line
in a sample of bright OB-supergiants (O7.5-B9) that aims at detecting
rotationally modulated changes potentially related to the existence of
large-scale wind structures. A total of 22 objects were monitor ed during 36
nights spread over 6 months in 2001-2002. Coordinated broad-band photometric
observations were also obtained for some targets. Conspicuous evidence for
variability in H\alpha is found for the stars displaying a feature contaminated
by wind emission. Most changes take place on a daily time-scale, although
hourly variations are also occasionally detected. Convincing evidence for a
cyclical pattern of variability in H\alpha has been found in 2 stars: HD 14134
and HD 42087 (periodic signals are also detected in other stars, but
independent confirmation is required). Rotational modulation is suggested from
the similarity between the observed recurrence time-scales (in the range 13-25
days) and estimated periods of stellar rotation. We call attention to the
atypical case of HD 14134 which exhibits a clear 12.8-d periodicity both in the
photometric and in the spectroscopic data sets. This places this object among a
handful of early-type stars where one may observe a clear link between extended
wind structures and photospheric disturbances. Further modelling may test the
hypothesis that azimuthally-extended wind streams are responsible for the
patterns of spectral variability in our target stars.