  Recommender Systems (RSs) have become increasingly important in many
application domains, such as digital marketing. Conventional RSs often need to
collect users' data, centralize them on the server-side, and form a global
model to generate reliable recommendations. However, they suffer from two
critical limitations: the personalization problem that the RSs trained
traditionally may not be customized for individual users, and the privacy
problem that directly sharing user data is not encouraged. We propose
Personalized Federated Recommender Systems (PersonalFR), which introduces a
personalized autoencoder-based recommendation model with Federated Learning
(FL) to address these challenges. PersonalFR guarantees that each user can
learn a personal model from the local dataset and other participating users'
data without sharing local data, data embeddings, or models. PersonalFR
consists of three main components, including AutoEncoder-based RSs (ARSs) that
learn the user-item interactions, Partially Federated Learning (PFL) that
updates the encoder locally and aggregates the decoder on the server-side, and
Partial Compression (PC) that only computes and transmits active model
parameters. Extensive experiments on two real-world datasets demonstrate that
PersonalFR can achieve private and personalized performance comparable to that
trained by centralizing all users' data. Moreover, PersonalFR requires
significantly less computation and communication overhead than standard FL
baselines.


  The space-air-ground integrated network (SAGIN) is a pivotal architecture to
support ubiquitous connectivity in the upcoming 6G era. Inter-operator resource
and service sharing is a promising way to realize such a huge network,
utilizing resources efficiently and reducing construction costs. Given the
rationality of operators, the configuration of resources and services in SAGIN
should focus on both the overall system performance and individual benefits of
operators. Motivated by emerging symbiotic communication facilitating mutual
benefits across different radio systems, we investigate the resource and
service sharing in SAGIN from a symbiotic communication perspective in this
paper. In particular, we consider a SAGIN consisting of a ground network
operator (GNO) and a satellite network operator (SNO). Specifically, we aim to
maximize the weighted sum rate (WSR) of the whole SAGIN by jointly optimizing
the user association, resource allocation, and beamforming. Besides, we
introduce a sharing coefficient to characterize the revenue of operators.
Operators may suffer revenue loss when only focusing on maximizing the WSR. In
pursuit of mutual benefits, we propose a mutual benefit constraint (MBC) to
ensure that each operator obtains revenue gains. Then, we develop a centralized
algorithm based on the successive convex approximation (SCA) method.
Considering that the centralized algorithm is difficult to implement, we
propose a distributed algorithm based on Lagrangian dual decomposition and the
consensus alternating direction method of multipliers (ADMM). Finally, we
provide extensive numerical simulations to demonstrate the effectiveness of the
two proposed algorithms, and the distributed optimization algorithm can
approach the performance of the centralized one.


  This paper describes my talk given to the 27th Johns Hopkins Workshop:
Symmetries and Mysteries of M Theory, G\"oteborg, Sweden, 24-26 August, 2003.
After a brief introduction to the lightcone worldsheet formalism for summing
the planar diagrams of field theory, I explain how the {\it uv} divergences of
quantum field theory translate to the new language of string. It is shown
through one loop that, at least for scalar cubic vertices, the counter-terms
necessary for Poincar\'e invariance in space-time dimensions $D\leq 6$ are
indeed local on the worldsheet. The extension to cover the case of gauge field
vertices will be more complicated due to the extra divergences at $p^+=0$ in
lightcone gauge.


  The mean exit time escaping basin of attraction in the presence of white
noise is of practical importance in various scientific fields. In this work, we
propose a strategy to control mean exit time of general stochastic dynamical
systems to achieve a desired value based on the quasipotential concept and
machine learning. Specifically, we develop a neural network architecture to
compute the global quasipotential function. Then we design a systematic
iterated numerical algorithm to calculate the controller for a given mean exit
time. Moreover, we identify the most probable path between metastable
attractors with help of the effective Hamilton-Jacobi scheme and the trained
neural network. Numerical experiments demonstrate that our control strategy is
effective and sufficiently accurate.


  We introduce a new class of finite dimensional algebras, called extended
canonical, investigate their derived categories and study the spectral behavior
of their Coxeter transformations. The subject relates to the triangulated
categories of (graded) singularities introduced by R. Buchweitz (1987) and D.
Orlov (2004).


  This paper addresses the following question of Oort: "Are there any postive
dimensional locally symmetric subvarieties of the moduli space of abelian
varieties that are contained in the jacobian locus and contain the jacobian of
at least one smooth curve? Some partial results are given.


  The ability of quantum computers to directly manipulate and analyze quantum
states stored in quantum memory allows them to learn about aspects of our
physical world that would otherwise be invisible given a modest number of
measurements. Here we investigate a new learning resource which could be
available to quantum computers in the future -- measurements on the unknown
state accompanied by its complex conjugate $\rho \otimes \rho^\ast$. For a
certain shadow tomography task, we surprisingly find that measurements on only
copies of $\rho \otimes \rho^\ast$ can be exponentially more powerful than
measurements on $\rho^{\otimes K}$, even for large $K$. This expands the class
of provable exponential advantages using only a constant overhead quantum
memory, or minimal quantum memory, and we provide a number of examples where
the state $\rho^\ast$ is naturally available in both computational and physical
applications. In addition, we precisely quantify the power of classical shadows
on single copies under a generalized Clifford ensemble and give a class of
quantities that can be efficiently learned. The learning task we study in both
the single copy and quantum memory settings is physically natural and
corresponds to real-space observables with a limit of bosonic modes, where it
achieves an exponential improvement in detecting certain signals under a noisy
background. We quantify a new and powerful resource in quantum learning, and we
believe the advantage may find applications in improving quantum simulation,
learning from quantum sensors, and uncovering new physical phenomena.


  We investigate the spatial distributions and production mechanisms of
vorticity and turbulent kinetic energy around a finite NACA 0018 wing with
square wingtip profile at $Re_c=10^4$ and $10^{\circ}$ angle of attack with the
aid of Direct Numerical Simulation (DNS). The analysis focuses on the highly
inhomogeneous region around the tip and the near wake; this region is highly
convoluted, strongly three-dimensional, and far from being self-similar. The
flow separates close to the leading edge creating a large, open recirculation
zone around the central part of the wing. In the proximity of the tip, the flow
remains attached but another smaller recirculation zone forms closer to the
trailing edge; this zone strongly affects the development of main wing tip
vortex. The early formation mechanisms of three vortices close to the leading
edge are elucidated and discussed. More specifically, we analyse the role of
vortex stretching/compression and tilting, and how it affects the strength of
each vortex as it approaches the trailing edge. We find that the
three-dimensional flow separation at the sharp tip close to the leading edge
plays an important role on the subsequent vortical flow development on the
suction side. The production of turbulent kinetic energy and Reynolds stresses
is also investigated and discussed in conjunction with the identified vortex
patterns. The detailed analysis of the mechanisms that sustain vorticity and
turbulent kinetic energy improves our understanding of these highly three
dimensional, non-equilibrium flows and can lead to better actuation methods to
manipulate these flows.


  The red-giant branch (RGB) in globular clusters is extended to larger
brightness if the degenerate helium core loses too much energy in "dark
channels." Based on a large set of archival observations, we provide
high-precision photometry for the Galactic globular cluster M5 (NGC 5904),
allowing for a detailed comparison between the observed tip of the RGB with
predictions based on contemporary stellar evolution theory. In particular, we
derive 95% confidence limits of $g_{ae}<4.3\times10^{-13}$ on the
axion-electron coupling and $\mu_\nu<4.5\times10^{-12}\,\mu_{\rm B}$ (Bohr
magneton $\mu_{\rm B}=e/2m_e$) on a neutrino dipole moment, based on a detailed
analysis of statistical and systematic uncertainties. The cluster distance is
the single largest source of uncertainty and can be improved in the future.


  We report the first demonstration of an inductively coupled magnetic ring
trap for cold atoms. A uniform, ac magnetic field is used to induce current in
a copper ring, which creates an opposing magnetic field that is time-averaged
to produce a smooth cylindrically symmetric ring trap of radius 5 mm. We use a
laser-cooled atomic sample to characterise the loading efficiency and
adiabaticity of the magnetic potential, achieving a vacuum-limited lifetime in
the trap. This technique is suitable for creating scalable toroidal waveguides
for applications in matterwave interferometry, offering long interaction times
and large enclosed areas.


  In this paper, we describe the irreducible representations and give a
dimension formula for the Framisation of the Temperley-Lieb algebra. We then
prove that the Framisation of the Temperley-Lieb algebra is isomorphic to a
direct sum of matrix algebras over tensor products of classical Temperley-Lieb
algebras. This allows us to construct a basis for it. We also study in a
similar way the Complex Reflection Temperley-Lieb algebra.


  Microservices have become popular in the past few years, attracting the
interest of both academia and industry. Despite of its benefits, this new
architectural style still poses important challenges, such as resilience,
performance and evolution. Self-adaptation techniques have been applied
recently as an alternative to solve or mitigate those problems. However, due to
the range of quality attributes that affect microservice architectures, many
different self-adaptation strategies can be used. Thus, to understand the
state-of-the-art of the use of self-adaptation techniques and mechanisms in
microservice-based systems, this work conducted a systematic mapping, in which
21 primary studies were analyzed considering qualitative and quantitative
research questions. The results show that most studies focus on the Monitor
phase (28.57%) of the adaptation control loop, address the self-healing
property (23.81%), apply a reactive adaptation strategy (80.95%) in the system
infrastructure level (47.62%) and use a centralized approach (38.10%). From
those, it was possible to propose some research directions to fill existing
gaps.


  We propose an approach to measuring nonresonant coupled systems, which gives
a parametrically smaller error than the conventional fast projective
measurements. The approach takes into account that, due to the coupling,
excitations are not entirely localized on individual systems. It combines high
spectral selectivity of the detector with temporal resolution and uses the
ideas of the quantum diffusion theory. The results bear on quantum computing
with perpetually coupled qubits.


  We study quantum effects of strong driving field applied to dissipative
hybrid qubit-cavity system which are relevant for a realization of quantum
gates in superconducting quantum metamaterials. We demonstrate that effects of
strong and non-stationary drivings have significantly quantum nature and can
not be treated by means of mean-field approximation. This is shown from a
comparison of steady state solution of the standard Maxwell-Bloch equations and
numerical solution of Lindblad equation on a density matrix. We show that
mean-field approach provides very good agreement with the density matrix
solution at not very strong drivings $f<f^*$ but at $f>f^*$ a growing value of
quantum correlations between fluctuations in qubit and photon sectors changes a
behavior of the system. We show that in regime of non-adiabatic switching on of
the driving such a quantum correlations influence a dynamics of qubit and
photons even at weak $f$.


  The recent PAMELA and ATIC/Fermi/HESS experiments have observed an excess of
electrons and positrons, but not anti-protons, in the high energy cosmic rays.
To explain this result, we construct a decaying hidden dark matter model in
string theory compactification that incorporates the following two ingredients,
the hidden dark matter scenario in warped compactification and the
phenomenological proposal of hidden light particles that decay to the Standard
Model. In this model, on higher dimensional warped branes, various warped
Kaluza-Klein particles and the zero-mode of gauge field play roles of the
hidden dark matter or mediators to the Standard Model.


  We present a multi-process application called HISTEX (HISTory EXerciser),
which executes input histories in a generic transactional notation on
commercial DBMS platforms. HISTEX could be used to discover potential errors in
the implementation of Isolation Levels by Relational Database Management
Systems or cases where a system behaves over restrictively. It can also be used
for performance measurements related to database workloads executing on real
database systems instead of simulated environments. HISTEX has been implemented
in C by utilizing Embedded SQL. However, many of its ideas could be
reincarnated in new implementations that could rely on other database
connectivity paradigms such as JDBC, JPA etc. We expect that by presenting some
of the ideas behind its development we could re-invigorate some fresh interest
and involvement in the research community regarding such tools.


  Linear magnetization dynamics in the presense of a thermal bath is analyzed
for two general classes of microscopic damping mechanisms. The resulting
stochastic differential equations are always in the form of a damped harmonic
oscillator driven by a thermal field. The damping term contains both the
interaction mechanisms and the symmetry of the magnetic system. Back
transformation from the oscillator coordinates to the magnetization variables
results in a macroscopic tensor form of damping that reflects the system
anisotropy. Scalar Landau-Lifshitz-Gilbert damping term is valid only for
systems with axial symmetry. Analysis of FMR linewith measurements versus
frequency, temperature, and film thickness in NiFe films shows good agreement
with a combination of slow-relaxing impurity and magnon-electron confluence
processes.


  Permutations of correlated sequences of random variables appear naturally in
a variety of applications such as graph matching and asynchronous
communications. In this paper, the asymptotic statistical behavior of such
permuted sequences is studied. It is assumed that a collection of random
vectors is produced based on an arbitrary joint distribution, and the vectors
undergo a permutation operation. The joint typicality of the resulting permuted
vectors with respect to the original distribution is investigated. As an
initial step, permutations of pairs of correlated random vectors are
considered. It is shown that the probability of joint typicality of the
permuted vectors depends only on the number and length of the disjoint cycles
of the permutation. Consequently, it suffices to study typicality for a class
of permutations called 'standard permutations', for which, upper-bounds on the
probability of joint typicality are derived. The notion of standard
permutations is extended to a class of permutation vectors called 'Bell
permutation vectors'. By investigating Bell permutation vectors, upper-bounds
on the probability of joint typicality of permutations of arbitrary collections
of random sequences are derived.


  We consider the problem of energy-efficient on-line scheduling for
slice-parallel video decoders on multicore systems. We assume that each of the
processors are Dynamic Voltage Frequency Scaling (DVFS) enabled such that they
can independently trade off performance for power, while taking the video
decoding workload into account. In the past, scheduling and DVFS policies in
multi-core systems have been formulated heuristically due to the inherent
complexity of the on-line multicore scheduling problem. The key contribution of
this report is that we rigorously formulate the problem as a Markov decision
process (MDP), which simultaneously takes into account the on-line scheduling
and per-core DVFS capabilities; the power consumption of the processor cores
and caches; and the loss tolerant and dynamic nature of the video decoder's
traffic. In particular, we model the video traffic using a Direct Acyclic Graph
(DAG) to capture the precedence constraints among frames in a Group of Pictures
(GOP) structure, while also accounting for the fact that frames have different
display/decoding deadlines and non-deterministic decoding complexities. The
objective of the MDP is to minimize long-term power consumption subject to a
minimum Quality of Service (QoS) constraint related to the decoder's
throughput. Although MDPs notoriously suffer from the curse of dimensionality,
we show that, with appropriate simplifications and approximations, the
complexity of the MDP can be mitigated. We implement a slice-parallel version
of H.264 on a multiprocessor ARM (MPARM) virtual platform simulator, which
provides cycle-accurate and bus signal-accurate simulation for different
processors. We use this platform to generate realistic video decoding traces
with which we evaluate the proposed on-line scheduling algorithm in Matlab.


  Symmetries of Poisson manifolds are in general quantized just to symmetries
up to homotopy of the quantized algebra of functions. It is therefore
interesting to study symmetries up to homotopy of Poisson manifolds. We notice
that they are equivalent to Poisson principal bundles and describe their
quantization to symmetries up to homotopy of the quantized algebras of
functions.


  K-Means clustering algorithm is one of the most commonly used clustering
algorithms because of its simplicity and efficiency. K-Means clustering
algorithm based on Euclidean distance only pays attention to the linear
distance between samples, but ignores the overall distribution structure of the
dataset (i.e. the fluid structure of dataset). Since it is difficult to
describe the internal structure of two data points by Euclidean distance in
high-dimensional data space, we propose a new distance measurement, namely,
view-distance, and apply it to the K-Means algorithm. On the classical manifold
learning datasets, S-curve and Swiss roll datasets, not only this new distance
can cluster the data according to the structure of the data itself, but also
the boundaries between categories are neat dividing lines. Moreover, we also
tested the classification accuracy and clustering effect of the K-Means
algorithm based on view-distance on some real-world datasets. The experimental
results show that, on most datasets, the K-Means algorithm based on
view-distance has a certain degree of improvement in classification accuracy
and clustering effect.


  In 1979, Lusztig proposed a cohomological construction of supercuspidal
representations of reductive $p$-adic groups, analogous to Deligne-Lusztig
theory for finite reductive groups. In this paper we establish a new instance
of Lusztig's program. Precisely, let $X$ be the $p$-adic Deligne-Lusztig
ind-scheme associated to a division algebra $D$ of invariant k/n over a
non-Archimedean local field $K$. We study its homology groups by establishing a
Deligne-Lusztig theory for families of finite unipotent groups that arise as
subquotients of $D^\times$. The homology of $X$ induces a natural
correspondence between quasi-characters of the (multiplicative group of the)
unramified degree-$n$ extension of $K$ and representations of $D^{\times}$. For
a broad class of characters $\theta,$ we show that the representation
$H_\bullet(X)[\theta]$ is irreducible and concentrated in a single degree.
Moreover, we show that this correspondence matches the bijection given by local
Langlands and Jacquet-Langlands. As a corollary, we obtain a geometric
realization of Jacquet-Langlands transfers between representations of division
algebras.


  Ellenberg proved that the abc conjecture would follow if this conjecture were
known for sums $a+b=c$ such that $D\mid abc$ for some integer~$D$. Mochizuki
proved a theorem with an opposite restriction, that the full abc conjecture
would follow if it were known for abc sums that are not highly divisible. We
prove both theorems for general number fields.


  Many datasets such as market basket data, text or hypertext documents, and
sensor observations recorded in different locations or time periods, are
modeled as a collection of sets over a ground set of keys. We are interested in
basic aggregates such as the weight or selectivity of keys that satisfy some
selection predicate defined over keys' attributes and membership in particular
sets. This general formulation includes basic aggregates such as the Jaccard
coefficient, Hamming distance, and association rules.
  On massive data sets, exact computation can be inefficient or infeasible.
Sketches based on coordinated random samples are classic summaries that support
approximate query processing.
  Queries are resolved by generating a sketch (sample) of the union of sets
used in the predicate from the sketches these sets and then applying an
estimator to this union-sketch.
  We derive novel tighter (unbiased) estimators that leverage sampled keys that
are present in the union of applicable sketches but excluded from the union
sketch. We establish analytically that our estimators dominate estimators
applied to the union-sketch for {\em all queries and data sets}. Empirical
evaluation on synthetic and real data reveals that on typical applications we
can expect a 25%-4 fold reduction in estimation error.


  Instabilities of transverse waves due to a constant magnetic field in a
non-degenerate quantum electron-ion plasmas are studied. A new type of
cyclotron oscillation with a small growth rate is disclosed. Excitation of a
new quantum mode is also revealed. Furthermore, the kinetic instabilities of
Alfven waves are discussed and the growth rates are obtained. A novel branch of
waves that we call a magnetic quantum string waves is found.


  We discuss the extraction of ground-state parameters, such as decay constants
and form factors, from two- and three-point dispersive sum rules, making use of
a quantum-mechanical potential model. This model provides a unique possibility
to probe the reliability and the accuracy of the method of sum rules: one
obtains the bound-state parameters by the standard procedures adopted in sum
rules, and compares these results with the exact values, known in the potential
model. We demonstrate the presence of uncontrollable uncertainties in the
ground-state parameters obtained from sum rules and estimate their magnitude.
The uncontrolled uncertainties in ground-state form factors are shown to be
typically much larger than those in the decay constants. In the example
presented, the uncontrolled systematic error in the extracted form factor is
found to exceed the 10% level.


  These notes are based on work done in collaboration with Frank Ferrari. We
show how to determine the spectra of stable BPS states in $N=2$ supersymmetric
$SU(2)$ Yang-Mills theories that are asymptotically free, i.e. without and with
$N_f=1,2,3$ quark hypermultiplets. In all cases: $\bullet$ There is a curve of
marginal stability diffeomorphic to a circle and going through all (finite)
singular points of moduli space. $\bullet$ The BPS spectra are discontinuous
across these curves. $\bullet$ The strong-coupling spectra (inside the curves)
contain only those BPS states that can become massless and are responsible for
the singularities. Except for $N_f=3$, they form a multiplet (with different
masses) of the broken global discrete symmetry. $\bullet$ All other
semi-classical BPS states must and do decay consistently when crossing the
curves. $\bullet$ The weak-coupling, i.e. semi-classical BPS spectra, contain
no magnetic charges larger than one for $N_f=0,1,2$ and no magnetic charges
larger than two for $N_f=3$.


  Long period comet C/2021 A1 (Leonard) will approach Venus to within 0.029 au
on 2021 December 18 and may subsequently graze the planet with its dust trail
less than two days later. We observed C/2021 A1 with the Lowell Discovery
Telescope on 2021 January 13 and March 3, as well as with the Palomar Hale
Telescope on 2021 March 20, while the comet was inbound at heliocentric
distances of r=4.97 au, 4.46 au, and 4.28 au, respectively. Tail morphology
suggests that the dust is optically dominated by ~0.1-1 mm radius grains
produced in the prior year. Neither narrowband imaging photometry nor
spectrophotometry reveal any definitive gas emission, placing 3-sigma upper
bounds on CN production of <1e23 molec/s at both of the latter two epochs.
Trajectory analysis indicates that large (>1 mm) grains ejected at extremely
large heliocentric distances (r>30 au) are most strongly favored to reach
Venus. The flux of such meteors on Venus, and thus their potential direct or
indirect observability, is highly uncertain as the comet's dust production
history is poorly constrained at these distances, but will likely fall well
below the meteor flux from comet C/2013 A1 (Siding Spring)'s closer encounter
to Mars in 2014, and thus poses negligible risk to any spacecraft in orbit
around Venus. Dust produced in previous apparitions will not likely contribute
substantially to the meteor flux, nor will dust from any future activity apart
from an unlikely high speed (>0.5 km/s) dust outburst prior to the comet
reaching r~2 au in 2021 September.


  This paper gives a necessary and sufficient condition for Gorensteinness in
Rees algebras of the $d$-th power of parameter ideals in certain Noetherian
local rings of dimension $d\ge 2$. The main result of this paper produces many
Gorenstein Rees algebras over non-Cohen-Macaulay local rings. For example, the
Rees algebra $\mathcal{R}(\mathfrak{q}^d)=\oplus_{i\ge 0}\mathfrak{q}^{di}$ is
Gorenstein for every parameter ideal $\mathfrak{q}$ that is a reduction of the
maximal ideal in a $d$-dimensional Buchsbaum local ring of depth 1 and
multiplicity 2.


  We investigate the Membership Problem for hypergeometric sequences: given a
hypergeometric sequence $\langle u_n \rangle_{n=0}^\infty$ of rational numbers
and a target $t \in \mathbb{Q}$, decide whether $t$ occurs in the sequence. We
show decidability of this problem under the assumption that in the defining
recurrence $p(n)u_{n}=q(n)u_{n-1}$, the roots of the polynomials $p(x)$ and
$q(x)$ are all rational numbers. Our proof relies on bounds on the density of
primes in arithmetic progressions. We also observe a relationship between the
decidability of the Membership problem (and variants) and the Rohrlich-Lang
conjecture in transcendence theory.


  We show that the Ueno-Campana's threefold cannot be obtained as the blow-up
of any smooth threefold along a smooth centre, answering negatively a question
raised by Oguiso and Truong.


  We study axiomatic foundations for different classes of constant-function
automated market makers (CFMMs). We focus particularly on separability and on
different invariance properties under scaling. Our main results are an
axiomatic characterization of a natural generalization of constant product
market makers (CPMMs), popular in decentralized finance, on the one hand, and a
characterization of the Logarithmic Scoring Rule Market Makers (LMSR), popular
in prediction markets, on the other hand. The first class is characterized by
the combination of independence and scale invariance, whereas the second is
characterized by the combination of independence and translation invariance.
The two classes are therefore distinguished by a different invariance property
that is motivated by different interpretations of the num\'eraire in the two
applications.
  However, both are pinned down by the same separability property.
  Moreover, we characterize the CPMM as an extremal point within the class of
scale invariant, independent, symmetric AMMs with non-concentrated liquidity
provision. Our results add to a formal analysis of mechanisms that are
currently used for decentralized exchanges and connect the most popular class
of DeFi AMMs to the most popular class of prediction market AMMs.


  The flexibility-rigidity index (FRI) is a newly proposed method for the
construction of atomic rigidity functions. The FRI method analyzes protein
rigidity and flexibility and is capable of predicting protein B-factors without
resorting to matrix diagonalization. A fundamental assumption used in the FRI
is that protein structures are uniquely determined by various internal and
external interactions, while the protein functions, such as stability and
flexibility, are solely determined by the structure. As such, one can predict
protein flexibility without resorting to the protein interaction Hamiltonian.
Consequently, bypassing the matrix diagonalization, the original FRI has a
computational complexity of O(N^2). This work introduces a fast FRI (fFRI)
algorithm for the flexibility analysis of large macromolecules. The proposed
fFRI further reduces the computational complexity to O(N). Additionally, we
propose anisotropic FRI (aFRI) algorithms for the analysis of protein
collective dynamics. The aFRI algorithms admit adaptive Hessian matrices, from
a completely global 3N*3N matrix to completely local 3*3 matrices. However,
these local 3*3 matrices have built in much non-local correlation. Furthermore,
we compare the accuracy and efficiency of FRI with some {established}
approaches to flexibility analysis, namely, normal mode analysis (NMA) and
Gaussian network model (GNM). The accuracy of the FRI method is tested. The
FRI, particularly the fFRI, is orders of magnitude more efficient and about 10%
more accurate overall than some of the most popular methods in the field. The
proposed fFRI is able to predict B-factors for alpha-carbons of the HIV virus
capsid (313,236 residues) in less than 30 seconds on a single processor using
only one core. Finally, we demonstrate the application of FRI and aFRI to
protein domain analysis.


  Pink has given a qualitative answer to the Mumford-Tate conjecture for
Drinfeld modules in the 90s. He showed that the image of the v-adic Galois
representation is v-adically open in the motivic Galois group for any prime v.
In contrast to this result, we provide a family of uniformizable Anderson
t-modules for which the Galois representations of their t-adic Tate-modules are
"far from" having t-adically open image in their motivic Galois groups.
Nevertheless, the image is still Zariski-dense in the motivic Galois group
which is in accordance to the Mumford-Tate conjecture. For the proof, we
explicitly determine the motivic Galois group as well as the Galois
representation for these t-modules.


  Radiation reaction acting on a charged particle moving at a stable circular
orbit of a magnetized black hole can lead to the shift of the orbital radius
outwards from the black hole. The effect causes increase of the energy and
angular momentum of the particle measured by an observer at rest at infinity.
In this note we show that "widening" of such orbits is independent of the field
configuration, however, it appears only in the cases with the external Lorentz
force acting outwards from the black hole. This condition corresponds to $q L B
> 0$, where $q$ and $L$ are the charge and angular momentum of the particle and
$B$ is intensity of the external magnetic field. As examples of the orbital
widening we consider two scenarios with an external homogeneous magnetic field
and a magnetic dipole field generated by a current loop around a Schwarzschild
black hole. We show that the orbital widening is accompanied by quasi-harmonic
oscillations of the particle which are considerably large in the magnetic
dipole fields. We also estimate the timescales of orbital widening from which
it follows that the effect can be relevant in the vicinity of stellar mass
black holes.


  Real-time robot motion planning in complex high-dimensional environments
remains an open problem. Motion planning algorithms, and their underlying
collision checkers, are crucial to any robot control stack. Collision checking
takes up a large portion of the computational time in robot motion planning.
Existing collision checkers make trade-offs between speed and accuracy and
scale poorly to high-dimensional, complex environments. We present a novel
space decomposition method using K-Means clustering in the Forward Kinematics
space to accelerate proxy collision checking. We train individual configuration
space models using Fastron, a kernel perceptron algorithm, on these decomposed
subspaces, yielding compact yet highly accurate models that can be queried
rapidly and scale better to more complex environments. We demonstrate this new
method, called Decomposed Fast Perceptron (D-Fastron), on the 7-DOF Baxter
robot producing on average 29x faster collision checks and up to 9.8x faster
motion planning compared to state-of-the-art geometric collision checkers.


  How much of the uncertainty in predicting measurement outcomes for
non-commuting quantum observables is genuinely quantum mechanical? We provide a
natural decomposition of the total entropic uncertainty of two non-commuting
observables into a classical component, and an intrinsically quantum mechanical
component. We show that the total quantum component in a state is never lower
or upper bounded by any state-independent quantities, but instead admits
"purity-based" lower bounds that generalize entropic formulations such as the
Maassen-Uffink relation. These relations reveal a non-trivial interplay between
quantum and classical randomness in any finite-dimensional state.


  The purpose of this paper is to study the properties of holomorphic Poisson
manifolds $(M,\pi)$ under the assumption of $\partial_{}\bar{\partial}$--lemma
or $\partial_{\pi}\bar{\partial}$--lemma. Under these assumptions,we show that
the Koszul--Brylinski homology can be recovered by the Dolbeault cohomology,
and prove that the DGLA
$(A_M^{\bullet,\bullet},\bar{\partial},[-,-]_{\partial_\pi})$ is
formal.Furthermore,we discuss the Maurer--Cartan elements of
$(A_M^{\bullet,\bullet}[[t]],\bar{\partial},[-,-]_{\partial_\pi})$ which induce
the deformations of complex structure of $M$.


  In this paper we consider first-order logic theorem proving and model
building via approximation and instantiation. Given a clause set we propose its
approximation into a simplified clause set where satisfiability is decidable.
The approximation extends the signature and preserves unsatisfiability: if the
simplified clause set is satisfiable in some model, so is the original clause
set in the same model interpreted in the original signature. A refutation
generated by a decision procedure on the simplified clause set can then either
be lifted to a refutation in the original clause set, or it guides a refinement
excluding the previously found unliftable refutation. This way the approach is
refutationally complete. We do not step-wise lift refutations but conflicting
cores, finite unsatisfiable clause sets representing at least one refutation.
The approach is dual to many existing approaches in the literature because our
approximation preserves unsatisfiability.


  Radiative decays $\pi^0({\pi^0}')\to\gamma+\gamma$,
${\pi^0}'\to\rho^0(\omega)+\gamma$, ${\rho^0}'(\omega')\to\pi^0+\gamma$, and
${\rho^0}'(\omega')\to{\pi^0}'+\gamma$ are considered in the framework of the
non-local SU(2)$\times$SU(2) NJL model. Radially excited mesons are described
with the help of polynomial form factor $f({k^\bot}^2)$, where $k^\bot$ is the
quark momentum transverse to the external meson momentum. In spite of mixing of
the ground and excited meson states in this model, the decay widths of
$\pi^0\to\gamma+\gamma$ and $\rho^0(\omega)\to\pi^0+\gamma$ are found to be in
good agreement with experimental data as in the standard local NJL model. Our
predictions for decay widths of radially excited mesons can be verified in
future experiments.


  Let $G = (VG, AG)$ be a directed graph with a set $S \subseteq VG$ of
terminals and nonnegative integer arc capacities $c$. A feasible multiflow is a
nonnegative real function $F(P)$ of "flows" on paths $P$ connecting distinct
terminals such that the sum of flows through each arc $a$ does not exceed
$c(a)$. Given $\mu \colon S \times S \to \R_+$, the \emph{$\mu$-value} of $F$
is $\sum_P F(P) \mu(s_P, t_P)$, where $s_P$ and $t_P$ are the start and end
vertices of a path $P$, respectively.
  Using a sophisticated topological approach, Hirai and Koichi showed that the
maximum $\mu$-value multiflow problem has an integer optimal solution when
$\mu$ is the distance generated by subtrees of a weighted directed tree and
$(G,S,c)$ satisfies certain Eulerian conditions.
  We give a combinatorial proof of that result and devise a strongly polynomial
combinatorial algorithm.


  We investigate the pairing tendencies in the hole-doped Haldane spin-1 chain.
To allow for doping, we extend the original spin chain Hamiltonian into a
fermionic model involving a two-orbital Hubbard chain at intermediate or strong
repulsive interaction strengths $U$, and for degenerate orbitals. At
half-filling and large $U$, the ferromagnetic Hund's coupling, $J_\mathrm{H}$,
generates effective spin-$1$ moments, with antiferromagnetic correlations
between sites. Using large-scale density matrix renormalization group
calculations, we study accurately the system's behavior under light
hole-doping. For $U=1.6$ in units of the non-interacting bandwidth and for
$J_\mathrm{H}/U\gtrsim 0.275$ we find that singlet pairing dominates the
long-distance physics, establishing this system as a promising platform for
repulsively mediated superconductivity. We provide concrete examples of
materials that could realize the physics described here. We also provide
evidence that the system approaches a Luther-Emery liquid state at large system
sizes, reminiscent of the behavior of doped one-orbital two-leg ladders at weak
coupling, which also have superconducting tendencies. The numerically
calculated central charge approaches one in the thermodynamic limit, indicating
a single gapless mode as is expected for the Luther-Emery state. Exponents
characterizing the power-law decays of singlet pair-pair and charge
density-density correlations are determined, and found to approximately satisfy
the Luther-Emery identity.


  Consider the indicator function $f$ of a two-dimensional percolation crossing
event. In this paper, the Fourier transform of $f$ is studied and sharp bounds
are obtained for its lower tail in several situations. Various applications of
these bounds are derived. In particular, we show that the set of exceptional
times of dynamical critical site percolation on the triangular grid in which
the origin percolates has dimension 31/36 a.s., and the corresponding dimension
in the half-plane is 5/9. It is also proved that critical bond percolation on
the square grid has exceptional times a.s. Also, the asymptotics of the number
of sites that need to be resampled in order to significantly perturb the global
percolation configuration in a large square is determined.


  Detecting the reflection symmetry plane of an object represented by a 3D
point cloud is a fundamental problem in 3D computer vision and geometry
processing due to its various applications, such as compression, object
detection, robotic grasping, 3D surface reconstruction, etc. There exist
several efficient approaches for solving this problem for clean 3D point
clouds. However, it is a challenging problem to solve in the presence of
outliers and missing parts. The existing methods try to overcome this challenge
mostly by voting-based techniques but do not work efficiently. In this work, we
proposed a statistical estimator-based approach for the plane of reflection
symmetry that is robust to outliers and missing parts. We pose the problem of
finding the optimal estimator for the reflection symmetry as an optimization
problem on a 2-Sphere that quickly converges to the global solution for an
approximate initialization. We further adapt the heat kernel signature for
symmetry invariant matching of mirror symmetric points. This approach helps us
to decouple the chicken-and-egg problem of finding the optimal symmetry plane
and correspondences between the reflective symmetric points. The proposed
approach achieves comparable mean ground-truth error and 4.5\% increment in the
F-score as compared to the state-of-the-art approaches on the benchmark
dataset.


  Aircraft target detection in SAR images is a challenging task due to the
discrete scattering points and severe background clutter interference.
Currently, methods with convolution-based or transformer-based paradigms cannot
adequately address these issues. In this letter, we explore diffusion models
for SAR image aircraft target detection for the first time and propose a novel
\underline{Diff}usion-based aircraft target \underline{Det}ection network
\underline{for} \underline{SAR} images (DiffDet4SAR). Specifically, the
proposed DiffDet4SAR yields two main advantages for SAR aircraft target
detection: 1) DiffDet4SAR maps the SAR aircraft target detection task to a
denoising diffusion process of bounding boxes without heuristic anchor size
selection, effectively enabling large variations in aircraft sizes to be
accommodated; and 2) the dedicatedly designed Scattering Feature Enhancement
(SFE) module further reduces the clutter intensity and enhances the target
saliency during inference. Extensive experimental results on the
SAR-AIRcraft-1.0 dataset show that the proposed DiffDet4SAR achieves 88.4\%
mAP$_{50}$, outperforming the state-of-the-art methods by 6\%. Code is
availabel at \href{https://github.com/JoyeZLearning/DiffDet4SAR}.


  In the aligned two-Higgs-doublet model, the alignment of Yukawa matrices in
flavour space guarantees the absence of tree-level flavour-changing neutral
currents, while allowing at the same time for new sources of CP violation,
implying potentially large effects in many low-energy processes. In this work
we study the constraints from exclusive radiative $B\to V\gamma$ decays, where
$V$ denotes a light vector meson. The current experimental data on the
CP-averaged branching ratios and the direct CP and isospin asymmetries are
analyzed. It is found that, while the branching ratios and direct CP
asymmetries do not constrain the parameter space much further compared to the
inclusive $B\to X_{s,d} \gamma$ decays, complementary constraints can be
obtained from the isospin asymmetries $\Delta(K^*\gamma)$ and
$\Delta(\rho\gamma)$. In addition, correlations between the various observables
in exclusive $B\to V\gamma$ and inclusive $B\to X_{s,d} \gamma$ decays are
investigated in detail, and predictions are made for several so far unmeasured
observables.


  In this paper, we present an efficient resource allocation with user
discrimination framework for 5G Wireless Systems to allocate multiple carriers
resources among users with elastic and inelastic traffic. Each application
running on the user equipment (UE) is assigned an application utility function.
In the proposed model, different classes of user groups are considered and
users are partitioned into different groups based on the carriers coverage
area. Each user has a minimum required application rate based on its class and
the type of its application. Our objective is to allocate multiple carriers
resources optimally among users, that belong to different classes, located
within the carriers' coverage area. We use a utility proportional fairness
approach in the utility percentage of the application running on the UE. Each
user is guaranteed a minimum quality of service (QoS) with a priority criterion
that is based on user's class and the type of application running on the UE. In
addition, we prove the existence of optimal solutions for the proposed resource
allocation optimization problem and present a multi-carrier resource allocation
with user discrimination algorithm. Finally, we present simulation results for
the performance of the proposed algorithm.


  Computing an optimal chain of fragments is a classical problem in string
algorithms, with important applications in computational biology. There exist
two efficient dynamic programming algorithms solving this problem, based on
different principles. In the present note, we show how it is possible to
combine the principles of two of these algorithms in order to design a hybrid
dynamic programming algorithm that combines the advantages of both algorithms.


  In a Vlasov equation, the destabilization of a homogeneous stationary state
is typically described by a continuous bifurcation characterized by strong
resonances between the unstable mode and the continuous spectrum. However, when
the reference stationary state has a flat top, it is known that resonances
drastically weaken, and the bifurcation becomes discontinuous. In this article,
we use a combination of analytical tools and precise numerical simulations to
demonstrate that this behavior is related to a codimension-two bifurcation,
which we study in details.


  We examine minimal seesaw mechanism in which the masses of light neutrinos
are described with tri/bi-maximal mixing in the basis where the charged-lepton
Yukawa matrix and heavy Majorana neutrino mass matrix are diagonal. We search
for all possible Dirac mass textures which contain at least one zero entry in
$3 \times 2$ matrix and evaluate the corresponding lepton asymmetries. We
present the baryon asymmetry in terms of a single low energy unknown, a
Majorana CP phase to be clued from neutrinoless double beta decay.


  We propose in this letter a relativistic coordinate independent
interpretation for Milgrom's acceleration $a_{0}=1.2 \times 10^{-8}
\hbox{cm/s}^{2}$ through a geometric constraint obtained from the product of
the Kretschmann invariant scalar times the surface area of 2--spheres defined
through suitable characteristic length scales for local and cosmic regimes,
described by Schwarzschild and Friedman--Lema\^\i tre--Robertson--Walker (FLRW)
geometries, respectively. By demanding consistency between these regimes we
obtain an appealing expression for the empirical (so far unexplained) relation
between the accelerations $a_0$ and $c H_0$.
  Imposing this covariant geometric criterion upon a FLRW model, yields a
dynamical equation for the Hubble scalar whose solution matches, to a very high
accuracy, the cosmic expansion rate of the $\Lambda$CDM concordance model fit
for cosmic times close to the present epoch. We believe that this geometric
interpretation of $a_0$ could provide relevant information for a deeper
understanding of gravity


  The thorny issue of relating information theory to cosmology is here
addressed by assuming a possible connection between quantum entanglement
measures and observable universe. In particular, we propose a cosmological toy
model, where the equation of state of the cosmological fluid, which drives the
today observed cosmic acceleration, can be inferred from quantum entanglement
between different cosmological epochs. In such a way the dynamical dark energy
results as byproduct of quantum entanglement.


  We use 4d ambitwistor string theory to derive new worldsheet formulae for
tree-level conformal supergravity amplitudes supported on refined scattering
equations. Unlike the worldsheet formulae for super-Yang-Mills or supergravity,
the scattering equations for conformal supergravity are not in general refined
by MHV degree. Nevertheless, we obtain a concise worldsheet formula for any
number of scalars and gravitons which we lift to a manifestly supersymmetric
formula using four types of vertex operators. The theory also contains states
with non-plane wave boundary conditions and we show that the corresponding
amplitudes can be obtained from plane-wave amplitudes by applying momentum
derivatives. Such derivatives are subtle to define since the formulae are
intrinsically four-dimensional and on-shell, so we develop a method for
computing momentum derivatives of spinor variables.


  We consider the asymptotic behavior of bounded solutions of the difference
equations of the form $x(n+1)=Bx(n) + y(n)$ in a Banach space $\X$, where
$n=1,2,...$, $B$ is a linear continuous operator in $\X$, and $(y(n))$ is a
sequence in $\X$ converging to 0 as $n\to\infty$. An obtained result with an
elementary proof says that if $\sigma (B) \cap \{|z|=1\} \subset \{1\}$, then
every bounded solution $x(n)$ has the property that $\lim_{n\to\infty}
(x(n+1)-x(n)) =0$. This result extends a theorem due to Katznelson-Tzafriri.
Moreover, the techniques of the proof are furthered to study the individual
stability of solutions of the discrete system. A discussion on further
extensions is also given.


  We carry out simulated annealing and employ a generalized Kibble-Zurek
scaling hypothesis to study the 2D Ising spin glass with normal-distributed
couplings. The system has an equilibrium glass transition at temperature $T=0$.
From a scaling analysis when $T\rightarrow 0$ at different annealing
velocities, we extract the dynamic critical exponent $z$, i.e., the exponent
relating the relaxation time $\tau$ to the system length $L$; $\tau\sim L^z$.
We find $z=13.6 \pm 0.4$ for both the Edwards-Anderson spin-glass order
parameter and the excess energy. This is different from a previous study of the
system with bimodal couplings [S. J. Rubin, N. Xu, and A. W. Sandvik, Phys.
Rev. E {\bf 95}, 052133 (2017)] where the dynamics is faster and the above two
quantities relax with different exponents (and that of the energy is larger).
We here argue that the different behaviors arise as a consequence of the
different low-energy landscapes---for normal-distributed couplings the ground
state is unique (up to a spin reflection) while the system with bimodal
couplings is massively degenerate. Our results reinforce the conclusion of
anomalous entropy-driven relaxation behavior in the bimodal Ising glass. In the
case of a continuous coupling distribution, our results presented here indicate
that, although Kibble-Zurek scaling holds, the perturbative behavior normally
applying in the slow limit breaks down, likely due to quasi-degenerate states,
and the scaling function takes a different form.


  This thesis deals with the study of dynamical properties of
out-of-equilibrium quantum systems. We introduce in particular a general class
of Spin-Boson models, which describe for example light-matter interaction or
dissipative phenomena. We contribute to the development of a stochastic
approach to describe the spin dynamics in these models. In this context, the
effect of the bosonic environment is encapsulated into additional stochastic
degrees of freedom whose time-correlations are determined by spectral
properties of the bosonic environment. We use this approach to study many-body
phenomena such as the dissipative quantum phase transition induced by an ohmic
bosonic environment. Synchronization phenomena as well as dissipative
topological transitions are identified. We also progress in the study of arrays
of interacting light-matter systems. These theoretical developments follow
recent experimental achievements, which could ensure a quantitative study of
these phenomena. This notably includes ultra-cold atoms, trapped ions and
cavity and circuit electrodynamics setups. We finally investigate hybrid
systems comprising electronic quantum dots coupled to electromagnetic
resonators, which enable us to provide a spectroscopic analysis of many-body
phenomena linked to the Kondo effect. We also introduce thermoelectric
applications in these devices.


  A new approximation of the cluster variational method is introduced for the
three-dimensional Ising model on the simple cubic lattice. The maximal cluster
is, as far as we know, the largest ever used in this method. A message-passing
algorithm, generalized belief propagation, is used to minimize the variational
free energy. Convergence properties and performance of the algorithm are
investigated. The approximation is used to compute the spontaneous
magnetization, which is then compared to previous results. Using the present
results as the last step in a sequence of three cluster variational
approximations, an extrapolation is obtained which captures the leading
critical behaviour with a good accuracy.


  We consider the Newtonian planar three-body problem, defining a syzygy
(velocity syzygy) as a configuration where the positions (velocities) of the
three bodies become collinear. We demonstrate that if the total energy is
negative, every collision-free solution has an infinite number of velocity
syzygies. Specifically, the velocities of the three bodies become parallel
within every interval of time containing three consecutive syzygies. Using
comparison theory for matrix Riccati equations, we derive new upper and lower
bounds on the moments when syzygies occur.


  The electronic ground state of a periodic system is usually described in
terms of extended Bloch orbitals, but an alternative representation in terms of
localized "Wannier functions" was introduced by Gregory Wannier in 1937. The
connection between the Bloch and Wannier representations is realized by
families of transformations in a continuous space of unitary matrices, carrying
a large degree of arbitrariness. Since 1997, methods have been developed that
allow one to iteratively transform the extended Bloch orbitals of a
first-principles calculation into a unique set of maximally localized Wannier
functions, accomplishing the solid-state equivalent of constructing localized
molecular orbitals, or "Boys orbitals" as previously known from the chemistry
literature. These developments are reviewed here, and a survey of the
applications of these methods is presented. This latter includes a description
of their use in analyzing the nature of chemical bonding, or as a local probe
of phenomena related to electric polarization and orbital magnetization.
Wannier interpolation schemes are also reviewed, by which quantities computed
on a coarse reciprocal-space mesh can be used to interpolate onto much finer
meshes at low cost, and applications in which Wannier functions are used as
efficient basis functions are discussed. Finally the construction and use of
Wannier functions outside the context of electronic-structure theory is
presented, for cases that include phonon excitations, photonic crystals, and
cold-atom optical lattices.


  The appearance of scalar/moduli fields in the early universe, as motivated by
string theory, naturally leads to non-thermal "moduli cosmology". Such
cosmology provides a consistent framework where the generation of radiation,
baryons, and dark matter can occur while maintaining successful Big Bang
Nucleosynthesis and avoiding the cosmological moduli problem. We present a
relatively economical construction with moduli cosmology, building on a variety
of string-inspired components (e.g. supersymmetry, discrete symmetries,
Green-Schwarz anomaly cancellation). We address a range of outstanding problems
of particle physics and cosmology simultaneously, including the fermion mass
hierarchy and flavor puzzle, the smallness of neutrino masses, baryogenesis and
dark matter. Our setup, based on discrete $\mathrm{Z}_{12}^{R}$ symmetry and
anomalous $\mathrm{U}(1)_A$, is void of the usual issues plaguing the Minimal
Supersymmetric Standard Model, i.e. the $\mu$-problem and the overly-rapid
proton decay due to dimension-4,-5 operators. The model is compatible with
$\mathrm{SU}(5)$ Grand Unification. The smallness of Dirac neutrino masses is
automatically established by requiring the cancellation of mixed
gravitational-gauge anomalies. The decay of the moduli field provides a common
origin for the baryon number and dark matter abundance, explaining the observed
cosmic coincidences, $\Omega_{B} \sim \Omega_{DM}$.


  This paper deals with the use of hybrid simulation to build and compose
heterogeneous simulation scenarios that can be proficiently exploited to model
and represent the Internet of Things (IoT). Hybrid simulation is a methodology
that combines multiple modalities of modeling/simulation. Complex scenarios are
decomposed into simpler ones, each one being simulated through a specific
simulation strategy. All these simulation building blocks are then synchronized
and coordinated. This simulation methodology is an ideal one to represent IoT
setups, which are usually very demanding, due to the heterogeneity of possible
scenarios arising from the massive deployment of an enormous amount of sensors
and devices. We present a use case concerned with the distributed simulation of
smart territories, a novel view of decentralized geographical spaces that,
thanks to the use of IoT, builds ICT services to manage resources in a way that
is sustainable and not harmful to the environment. Three different simulation
models are combined together, namely, an adaptive agent-based parallel and
distributed simulator, an OMNeT++ based discrete event simulator and a
script-language simulator based on MATLAB. Results from a performance analysis
confirm the viability of using hybrid simulation to model complex IoT
scenarios.


  We present a deep model that can accurately produce dense depth maps given an
RGB image with known depth at a very sparse set of pixels. The model works
simultaneously for both indoor/outdoor scenes and produces state-of-the-art
dense depth maps at nearly real-time speeds on both the NYUv2 and KITTI
datasets. We surpass the state-of-the-art for monocular depth estimation even
with depth values for only 1 out of every ~10000 image pixels, and we
outperform other sparse-to-dense depth methods at all sparsity levels. With
depth values for 1/256 of the image pixels, we achieve a mean absolute error of
less than 1% of actual depth on indoor scenes, comparable to the performance of
consumer-grade depth sensor hardware. Our experiments demonstrate that it would
indeed be possible to efficiently transform sparse depth measurements obtained
using e.g. lower-power depth sensors or SLAM systems into high-quality dense
depth maps.


  In this paper, we consider the following $k$-dispersion problem. Given a set
$S$ of $n$ points placed in the plane in a convex position, and an integer $k$
($0<k<n$), the objective is to compute a subset $S'\subset S$ such that
$|S'|=k$ and the minimum distance between a pair of points in $S'$ is
maximized. Based on the bounded search tree method we propose an exact
fixed-parameter algorithm in $O(2^k(n^2\log n+n(\log^2 n)(\log k)))$ time, for
this problem, where $k$ is the parameter. The proposed exact algorithm is
better than the current best exact exponential algorithm
[$n^{O(\sqrt{k})}$-time algorithm by Akagi et al.,(2018)] whenever
$k<c\log^2{n}$ for some constant $c$. We then present an $O(\log{n})$-time
$\frac{1}{2\sqrt{2}}$-approximation algorithm for the problem when $k=3$ if the
points are given in convex position order.


  Using $980~\rm fb^{-1}$ of data on and around the $\Upsilon(nS)(n=1,2,3,4,5)$
resonances collected with the Belle detector at the KEKB asymmetric-energy
$e^+e^-$ collider, the two-photon process $\gamma\gamma\to \gamma\psi(2S)$ is
studied from the threshold to $4.2~{\rm GeV}$ for the first time. Two
structures are seen in the invariant mass distribution of $\gamma\psi(2S)$: one
at $M_{R_1} = 3922.4\pm 6.5 \pm 2.0~{\rm MeV}/c^2$ with a width of
$\Gamma_{R_1} = 22\pm 17\pm 4~{\rm MeV}$, and another at $M_{R_2} = 4014.3\pm
4.0 \pm 1.5~{\rm MeV}/c^2$ with a width of $\Gamma_{R_2} = 4\pm 11 \pm 6~{\rm
MeV}$; the signals are parametrized with the incoherent sum of two Breit-Wigner
functions. The first structure is consistent with the $X(3915)$ or the
$\chi_{c2}(3930)$, and the local statistical significance is determined to be
$3.1\sigma$ with the systematic uncertainties included. The second matches none
of the known charmonium or charmoniumlike states, and its global significance
is determined to be $2.8\sigma$ including the look-elsewhere effect. The
production rates are $\Gamma_{\gamma\gamma}{\cal B}(R_1\to\gamma\psi(2S)) =
9.8\pm 3.6\pm 1.2~{\rm eV}$ assuming $(J^{PC}, |\lambda|) =(0^{++}, 0)$ or
$2.0\pm 0.7\pm 0.2~{\rm eV}$ with $(2^{++}, 2)$ for the first structure and
$\Gamma_{\gamma\gamma}{\cal B}(R_2\to\gamma\psi(2S)) = 6.2\pm 2.2\pm 0.8~{\rm
eV}$ with $(0^{++}, 0)$ or $1.2\pm 0.4\pm 0.2~{\rm eV}$ with $(2^{++}, 2)$ for
the second one. Here, the first errors are statistical and the second
systematic, and $\lambda$ is the helicity.


  Implementing image processing algorithms using FPGAs or ASICs can improve
energy efficiency by orders of magnitude over optimized CPU, DSP, or GPU code.
These efficiency improvements are crucial for enabling new applications on
mobile power-constrained devices, such as cell phones or AR/VR headsets.
Unfortunately, custom hardware is commonly implemented using a waterfall
process with time-intensive manual mapping and optimization phases. Thus, it
can take years for a new algorithm to make it all the way from an algorithm
design to shipping silicon. Recent improvements in hardware design tools, such
as C-to-gates High-Level Synthesis (HLS), can reduce design time, but still
require manual tuning from hardware experts.
  In this paper, we present HWTool, a novel system for automatically mapping
image processing and computer vision algorithms to hardware. Our system maps
between two domains: HWImg, an extensible C++ image processing library
containing common image processing and parallel computing operators, and
Rigel2, a library of optimized hardware implementations of HWImg's operators
and backend Verilog compiler. We show how to automatically compile HWImg to
Rigel2, by solving for interfaces, hardware sizing, and FIFO buffer allocation.
Finally, we map full-scale image processing applications like convolution,
optical flow, depth from stereo, and feature descriptors to FPGA using our
system. On these examples, HWTool requires on average only 11% more FPGA area
than hand-optimized designs (with manual FIFO allocation), and 33% more FPGA
area than hand-optimized designs with automatic FIFO allocation, and performs
similarly to HLS.


  Excitons are elementary optical excitation in semiconductors. The ability to
manipulate and transport these quasiparticles would enable excitonic circuits
and devices for quantum photonic technologies. Recently, interlayer excitons in
2D semiconductors have emerged as a promising candidate for engineering
excitonic devices due to their long lifetime, large exciton binding energy, and
gate tunability. However, the charge-neutral nature of the excitons leads to
weak response to the in-plane electric field and thus inhibits transport beyond
the diffusion length. Here, we demonstrate the directional transport of
interlayer excitons in bilayer WSe2 driven by the propagating potential traps
induced by surface acoustic waves (SAW). We show that at 100 K, the SAW-driven
excitonic transport is activated above a threshold acoustic power and reaches
20 mm, a distance at least ten times longer than the diffusion length and only
limited by the device size. Temperature-dependent measurement reveals the
transition from the diffusion-limited regime at low temperature to the acoustic
field-driven regime at elevated temperature. Our work shows that acoustic waves
are an effective, contact-free means to control exciton dynamics and transport,
promising for realizing 2D materials-based excitonic devices such as exciton
transistors, switches, and transducers up to room temperature.


  (21) Lutetia has been visited by Rosetta mission on July 2010 and observed
with a phase angle ranging from 0.15 to 156.8 degrees. The Baetica region,
located at the north pole has been extensively observed by OSIRIS cameras
system. Baetica encompass a region called North Pole Crater Cluster (NPCC),
shows a cluster of superposed craters which presents signs of variegation at
the small phase angle images. For studying the location, we used 187 images
distributed throughout 14 filter recorded by the NAC (Narrow Angle Camera) and
WAC (Wide Angle Camera) taken during the fly-by. We photometrically modeled the
region using Minnaert disk-function and Akimov phase function to finally
reconstruct a resolved spectral slope map at 5 and 20 degrees of phase angle.
We observed a dichotomy between Gallicum and Danuvius-Sarnus Labes in the NPCC,
but no significant phase reddening. In the next step, we applied the Hapke
(2008, 2012) model for the NAC F82+F22 (649.2 nm), WAC F13 (375 nm) and WAC F17
(631.6 nm), enabling us to compose the normal albedo and Hapke parameter maps
for NAC F82+F22. On Baetica, the 649 nm global properties are: geometric albedo
of 0.205+-0.005, the average single-scattering albedo of 0.181+-0.005, the
average asymmetric factor of -0.342+-0.003, the average shadow-hiding
opposition effect amplitude and width respectivelly of 0.824+-0.002 and
0.040+-0.0007, the average roughness slope of 11.45+-3 deg. and the average
porosity is 85+-0.2%. In the NPCC, the normal albedo variegation among the
craters walls reach 8% brighter for Gallicum Labes and 2% fainter for Danuvius
Labes. The Hapke parameter maps also show a dichotomy at the opposition effect
coefficients, single-scattering albedo and asymmetric factor, that may be
attributed to the maturation degree of the regolith or to compositonal
variation.


  The $N$-dimensional quantum Hamiltonian $ \hat{H} = -\frac{\hbar^2
{|\mathbf{q} } | }{2(\eta +| {\mathbf{q}} |)} {\mathbf{\nabla}}^2 -
\frac{k}{\eta + |{\mathbf{q}} |} $ is shown to be exactly solvable for any real
positive value of the parameter $\eta$. Algebraically, this Hamiltonian system
can be regarded as a new maximally superintegrable $\eta$-deformation of the
$N$-dimensional Kepler-Coulomb Hamiltonian while, from a geometric viewpoint,
this superintegrable Hamiltonian can be interpreted as a system on an
$N$-dimensional Riemannian space with nonconstant curvature. The eigenvalues
and eigenfunctions of the model are explicitly obtained, and the spectrum
presents a hydrogen-like shape for positive values of the deformation parameter
$\eta$ and of the coupling constant $k$.


  We propose a new scenario for early cosmology, where inflationary de Sitter
phase dynamically occurs. The effect emerges as a result of dynamics of the
topologically nontrivial sectors in expanding universe. Technically the effect
can be described in terms of the auxiliary fields which effectively describe
the dynamics of the topological sectors in a gauge theory. Inflaton in this
framework is an auxiliary topological non-propagating field with no canonical
kinetic term, similar to known topologically ordered phases in condensed matter
systems. We explain many deep questions in this framework using the so-called
weakly coupled "deformed QCD" toy model.While this theory is weakly coupled
gauge theory, it preserves all the crucial elements of strongly interacting
gauge theory, including confinement, nontrivial $\theta$ dependence, degeneracy
of the topological sectors, etc. We discuss a specific realization of these
ideas using a scaled up version of QCD, coined as \qcd, with the scale
M_{PL}\gg \Lbar\gg \sqrt[3]{M_{EW}^2M_{PL}}\sim 10^8 {\mathrm{GeV}}. If no
other fields are present in the system de Sitter phase will be the final
destination of evolution of the universe. If other interactions are present in
the system, the inflationary de Sitter phase lasts for a finite period of time.
The inflation starts from the thermal equilibrium state long after the \qcd
-confinement phase transition at temperature T_{i}\sim
\Lbar\sqrt{\frac{\Lbar}{M_{PL}}}. The end of inflation is triggered by the
coupling with gauge bosons from the Standard Model. The corresponding
interaction is unambiguously fixed by the triangle anomaly. Number of e-folds
in the \qcd-inflation framework is determined by the gauge coupling constant at
the moment of inflation, and estimated as N_{\rm inf}\sim \alpha_s^{-2}\sim
10^2.


  A base model of the high-resolution fiber-fed spectrograph is developed. In
combination with the SAO 1-meter telescope the spectrograph has the following
parameters: spectral resolution R=45000, the number of simultaneous registered
orders is 86 within spectral region 3850$\div$10850 \AA{}, echelle orders are
overlapping for $\lambda <9000$ \AA{}.


  We have taken deep $R$-band images of fields around five radiogalaxies:
0956+47, 1217+36, 3C256, 3C324 and 3C294 with $1<z<2$ . 0956+47 is found to
show a double nucleus. Our data on 1217+36 suggest the revision of its
classification as a radiogalaxy. We found a statistically significant excess of
bright ($19.5<R<22$) galaxies on scales of 2 arcmin around the radiogalaxies
(which have $R \approx 21.4$) in our sample. The excess has been determined
empirically to be at $\gtrsim 99.5\%$ level. It is remarkable that this excess
is not present for $22<R<23.75$ galaxies within the same area, suggesting that
the excess is not physically associated to the galaxies but due to intervening
groups and then related to gravitational lensing.


  In recent years, large language models (LLMs) have become increasingly
capable and can now interact with tools (i.e., call functions), read documents,
and recursively call themselves. As a result, these LLMs can now function
autonomously as agents. With the rise in capabilities of these agents, recent
work has speculated on how LLM agents would affect cybersecurity. However, not
much is known about the offensive capabilities of LLM agents.
  In this work, we show that LLM agents can autonomously hack websites,
performing tasks as complex as blind database schema extraction and SQL
injections without human feedback. Importantly, the agent does not need to know
the vulnerability beforehand. This capability is uniquely enabled by frontier
models that are highly capable of tool use and leveraging extended context.
Namely, we show that GPT-4 is capable of such hacks, but existing open-source
models are not. Finally, we show that GPT-4 is capable of autonomously finding
vulnerabilities in websites in the wild. Our findings raise questions about the
widespread deployment of LLMs.


  We explore how the splashback radius ($R_{\rm sp}$) of galaxy clusters,
measured using the number density of the subhalo population, changes based on
various selection criteria using the IllustrisTNG cosmological galaxy formation
simulation. We identify $R_{\rm sp}$ by extracting the steepest radial gradient
in a stacked set of clusters in 0.5 dex wide mass bins, with our clusters
having halo masses $10^{13} \leq M_{\rm 200, mean} / {\rm M}_\odot \leq
10^{15}$. We apply cuts in subhalo mass, galaxy stellar mass, $i$-band absolute
magnitude and specific star formation rate. We find that, generally, galaxies
of increasing mass and luminosity trace smaller measured splashback radii
relative to the intrinsic dark matter radius. We also show that quenched
galaxies may be used to reliably reconstruct the dark matter splashback radius.
This trend is likely due to changes in the galaxy population. Additionally, we
are able to reconcile different observational predictions that $R_{\rm sp}$
based upon galaxy number counts and dark matter may either align or show
significant offset (e.g. those using optically- or SZ-selected clusters)
through the selection functions that these studies employ. Finally, we
demonstrate that changes in $R_{\rm sp}$ measured through number counts are not
due to a simple change in galaxy abundance inside and outside of the cluster.


  Advanced driving functions, for assistance or full automation, require strong
guarantees to be deployed. This means that such functions may not be available
all the time, like now commercially available SAE Level 3 modes that are made
available only on some roads and at law speeds. The specification of such
restriction is described technically in the Operational Design Domain (ODD)
which is a fundamental concept for the design of automated driving systems
(ADS). In this work, we focus on the example of trajectory planning and control
which are crucial functions for SAE level 4+ vehicles and often rely on
model-based methods. Hence, the quality of the underlying models has to be
evaluated with respect to the ODD. Mathematical analyses such as uncertainty
and sensitivity analysis support the quantitative assessment of model quality
in general. In this paper, we present a new approach to assess the quality of
vehicle dynamics models using an ODD-centric sensitivity analysis. The
sensitivity analysis framework is implemented for a 10-DoF nonlinear
double-track vehicle dynamics model used inside a model-predictive trajectory
controller. The model sensitivity is evaluated with respect to given ODD and
maneuver parameters. Based on the results, ODD-compliant behavior generation
strategies with the goal of minimizing model sensitivity are outlined.


  We prove that the C*-algebra of a directed graph $E$ is liminal iff the graph
satisfies the finiteness condition: if $p$ is an infinite path or a path ending
with a sink or an infinite emitter, and if $v$ is any vertex, then there are
only finitely many paths starting with $v$ and ending with a vertex in $p$.
Moreover, C*(E) is Type I precisely when the circuits of $E$ are either
terminal or transitory, i.e., $E$ has no vertex which is on multiple circuits,
and $E$ satisfies the weaker condition: for any infinite path $\lambda$, there
are only finitely many vertices of $\lambda$ that get back to $\lambda$ in an
infinite number of ways.


  Given a random time, we characterize the set of martingales for which the
stopping theorems still hold. We also investigate how the stopping theorems are
modified when we consider arbitrary random times. To this end, we introduce
some families of martingales with remarkable properties. We also investigate,
in the Brownian setting, the relationships between a given random time and the
underlying Brownian Motion in the progressively enlarged filtration with
respect to this random time.


  We give a representation theoretical proof of Branson's classification of
minimal elliptic sums of generalized gradients. The original proof uses tools
of harmonic analysis, which as powerful as they are, seem to be specific for
the structure groups SO(n) and Spin(n). The different approach we propose is
based on the relationship between ellipticity and optimal Kato constants and on
the representation theory of so(n). Optimal Kato constants for elliptic
operators were computed by Calderbank, Gauduchon and Herzlich. We extend their
method to all generalized gradients (not necessarily elliptic) and recover
Branson's result, up to one special case. The interest of this method is that
it is better suited to be applied for classifying elliptic sums of generalized
gradients of G-structures, for other subgroups G of the special orthogonal
group.


  Starting from the observation that quite often the Earth's oscillating
electric field varies in amplitude, a mechanism is postulated that accounts for
these observations. That mechanism is the piezoelectric one driven by the M1
and K1 tidal components. It is demonstrated how the system: piezoelectricity
triggered in the lithosphere - M1 and K1 tidal components is activated and
produces the amplitude modulated Earth's oscillating electric field. This
procedure is linked to the strain load conditions met in the seismogenic area
before the occurrence of a large EQ. Peaks of the oscillating Earth's electric
field are tightly connected to the M1 peak tidal component and to the timing of
the occurrence of large EQs. Typical examples from real recordings of the
Earth's oscillating electric field, recorded by the ATH (Greece) monitoring
site, are given in order to verify the postulated detailed piezoelectric
mechanism.


  Hallucination has emerged as the most vulnerable aspect of contemporary Large
Language Models (LLMs). In this paper, we introduce the Sorry, Come Again (SCA)
prompting, aimed to avoid LLM hallucinations by enhancing comprehension
through: (i) optimal paraphrasing and (ii) injecting [PAUSE] tokens to delay
LLM generation. First, we provide an in-depth analysis of linguistic nuances:
formality, readability, and concreteness of prompts for 21 LLMs, and elucidate
how these nuances contribute to hallucinated generation. Prompts with lower
readability, formality, or concreteness pose comprehension challenges for LLMs,
similar to those faced by humans. In such scenarios, an LLM tends to speculate
and generate content based on its imagination (associative memory) to fill
these information gaps. Although these speculations may occasionally align with
factual information, their accuracy is not assured, often resulting in
hallucination. Recent studies reveal that an LLM often neglects the middle
sections of extended prompts, a phenomenon termed as lost in the middle. While
a specific paraphrase may suit one LLM, the same paraphrased version may elicit
a different response from another LLM. Therefore, we propose an optimal
paraphrasing technique to identify the most comprehensible paraphrase of a
given prompt, evaluated using Integrated Gradient (and its variations) to
guarantee that the LLM accurately processes all words. While reading lengthy
sentences, humans often pause at various points to better comprehend the
meaning read thus far. We have fine-tuned an LLM with injected [PAUSE] tokens,
allowing the LLM to pause while reading lengthier prompts. This has brought
several key contributions: (i) determining the optimal position to inject
[PAUSE], (ii) determining the number of [PAUSE] tokens to be inserted, and
(iii) introducing reverse proxy tuning to fine-tune the LLM for [PAUSE]
insertion.


  Trap models describe glassy dynamics as a stochastic process on a network of
configurations representing local energy minima. We study within this class the
paradigmatic Barrat-M\'ezard model, which has Glauber transition rates. Our
focus is on the effects of the network connectivity, where we go beyond the
usual mean field (fully connected) approximation and consider sparse networks,
specifically random regular graphs. We obtain the spectral density of
relaxation rates of the master operator using the cavity method, revealing very
rich behaviour as a function of network connectivity $c$ and temperature $T$.
We trace this back to a crossover from initially entropic barriers, resulting
from a paucity of downhill directions, to energy barriers that govern the
escape from local minima at long times. The insights gained are used to
rationalize the relaxation of the energy after a quench from high $T$, as well
as the corresponding correlation and persistence functions.


  We derive the representative Bernstein measure of the density of
$(X_{\alpha})^{-\alpha/(1-\alpha)}, 0 < \alpha < 1$, where $X_{\alpha}$ is a
positive stable random variable, as a Fox-H function. When $1-\alpha = 1/j$ for
some integer $j \geq 2$, the Fox H-function reduces to a Meijer G-function so
that the Kanter's random variable (see below) is closely related to a product
of $(j-1)$ independent Beta random variables. When $\alpha$ tends to 0, the
Bernstein measure becomes degenerate thereby agrees with Cressie's result for
the asymptotic behaviour of stable distributions for small values of $\alpha$.
Coming to free probability, our result makes more explicit that of Biane on the
density of its free analog. The paper is closed with analytic arguments
explaining the occurence of the Kanter's random variable in both the classical
and the free settings.


  A promising approach to improve the robustness and exploration in
Reinforcement Learning is collecting human feedback and that way incorporating
prior knowledge of the target environment. It is, however, often too expensive
to obtain enough feedback of good quality. To mitigate the issue, we aim to
rely on a group of multiple experts (and non-experts) with different skill
levels to generate enough feedback. Such feedback can therefore be inconsistent
and infrequent. In this paper, we build upon prior work -- Advise, a Bayesian
approach attempting to maximise the information gained from human feedback --
extending the algorithm to accept feedback from this larger group of humans,
the trainers, while also estimating each trainer's reliability. We show how
aggregating feedback from multiple trainers improves the total feedback's
accuracy and make the collection process easier in two ways. Firstly, this
approach addresses the case of some of the trainers being adversarial.
Secondly, having access to the information about each trainer reliability
provides a second layer of robustness and offers valuable information for
people managing the whole system to improve the overall trust in the system. It
offers an actionable tool for improving the feedback collection process or
modifying the reward function design if needed. We empirically show that our
approach can accurately learn the reliability of each trainer correctly and use
it to maximise the information gained from the multiple trainers' feedback,
even if some of the sources are adversarial.


  We make a theoretical prediction for the ratio of the dark energy to other
components in the Universe based on the scenario of the sequestering mechanism
which was recently proposed as one possible way to solve the cosmological
constant problem. In order to evaluate the value of dark energy and the others,
we assume a specific scale factor which describes the Big-Crunch scenario in
the scalar-tensor theory. We specify the parameter region where the one can
explain the observed dark energy-matter ratio.


  We implement dynamical decoupling techniques to mitigate noise and enhance
the lifetime of an entangled state that is formed in a superconducting flux
qubit coupled to a microscopic two-level system. By rapidly changing the
qubit's transition frequency relative to the two-level system, we realize a
refocusing pulse that reduces dephasing due to fluctuations in the transition
frequencies, thereby improving the coherence time of the entangled state. The
coupling coherence is further enhanced when applying multiple refocusing
pulses, in agreement with our $1/f$ noise model. The results are applicable to
any two-qubit system with transverse coupling, and they highlight the potential
of decoupling techniques for improving two-qubit gate fidelities, an essential
prerequisite for implementing fault-tolerant quantum computing.


  This study investigates human and ChatGPT text simplification and its
relationship to dependency distance. A set of 220 sentences, with increasing
grammatical difficulty as measured in a prior user study, were simplified by a
human expert and using ChatGPT. We found that the three sentence sets all
differed in mean dependency distances: the highest in the original sentence
set, followed by ChatGPT simplified sentences, and the human simplified
sentences showed the lowest mean dependency distance.


  Given any smooth toric surface S, we prove a SYM-HILB correspondence which
relates the 3-point, degree zero, extended Gromov-Witten invariants of the
n-fold symmetric product stack [Sym^n(S)] of S to the 3-point extremal
Gromov-Witten invariants of the Hilbert scheme Hilb^n(S) of n points on S. As
we do not specialize the values of the quantum parameters involved, this result
proves a strengthening of Ruan's Cohomological Crepant Resolution Conjecture
for the Hilbert-Chow morphism from Hilb^n(S) to Sym^n(S) and yields a method of
reconstructing the cup product for Hilb^n(S) from the orbifold invariants of
[Sym^n(S)].


  We use the fivebrane of M theory to study the $\theta$ dependence of four
dimensional $SU(N_c)$ super Yang-Mills and super QCD softly broken by a gaugino
mass. We compute the energy of the vacuum in the supergravity approximation.
The results obtained are in qualitative agreement with field theory. We also
study the $\theta$ dependence of the QCD string tension via the fivebrane.


  Several observed anomalies in neutrino oscillation data can be explained by a
hypothetical fourth neutrino separated from the three standard neutrinos by a
squared mass difference of a few eV^2. We show that this hypothesis can be
tested with a PBq (ten kilocurie scale) 144Ce or 106Ru antineutrino beta-source
deployed at the center of a large low background liquid scintillator detector.
In particular, the compact size of such a source could yield an
energy-dependent oscillating pattern in event spatial distribution that would
unabiguously determine neutrino mass differences and mixing angles.


  We present an enhanced design -- in terms of resolution flexibility, input
port position arbitrariness and frequency-range tunability -- of the planar
Rotman lens spectrum decomposer (RL-SD). This enhancement is achieved by
manipulating the output port locations through proper sampling of the
frequency-position law of the RL-SD, inserting a calibration array compensating
for frequency deviation induced by input modification and introducing port
switching, respectively. A complete design procedure is provided and two
enhanced RL-SD prototypes, with uniform port distribution and uniform frequency
resolution, respectively, are numerically and experimentally demonstrated.


  Motivated by the study of black attractors in 8D supergravity with 16
supersymmetries, we use the field theory approach and 8D supersymmetry with non
trivial central charges to shed light on the exact duality between heterotic
string on T^2 and type IIA on real connected and compact surfaces {\Sigma}2. We
investigate the two constraints that should be obeyed by {\Sigma}2 and give
their solutions in terms of intersecting 2-cycles as well their classification
using Dynkin diagrams of affine Kac-Moody algebras. It is shown as well that
the moduli space of these dual theories is given by
SO(1,1)x((SO(2,r+2))/(SO(2)xSO(r+2))) where r stands for the rank of the gauge
symmetry G_{r} of the 10D heterotic string on T^2. The remarkable cases
r=-2,-1,0 as well as other features are also investigated.


  Replacing conventional power sources by renewable sources in current power
grids drastically alters their structure and functionality. The resulting grid
will be far more decentralized with an distinctly different topology. Here we
analyze the impact of grid topologies on spontaneous synchronization,
considering regular, random and small-world topologies and focusing on the
influence of decentralization. We employ the classic model of power grids
modeling consumers and sources as second order oscillators. We first analyze
the global dynamics of the simplest non-trivial (two-node) network that exhibit
a synchronous (normal operation) state, a limit cycle (power outage) and
coexistence of both. Second, we estimate stability thresholds for the
collective dynamics of small network motifs, in particular star-like networks
and regular grid motifs. For larger networks we numerically investigate
decentralization scenarios finding that decentralization itself may support
power grids in reaching stable synchrony for lower lines transmission
capacities. Decentralization may thus be beneficial for power grids, regardless
of their special resulting topology. Regular grids exhibit a specific
transition behavior not found for random or small-world grids.


  We calculate the finite temperature X-ray photoemission spectroscopy for the
Falicov-Kimball model using a Weiner-Hopf sum equation approach. In the
metallic state, the core-hole spectral function shows two side peaks
corresponding to the creation of a core-hole on an empty site (or a doubly
occupied site) and also has two nearly degenerate central peaks (because of our
choice of the model parameters) corresponding to the creation of a core-hole on
a singly occupied site. The nearly doubly degenerate central peaks merge into a
single peak at higher temperatures. In the insulating state, we obtain two
peaks and a strongly temperature dependent low-energy peak corresponding to the
creation of a core-hole on a thermally excited empty site. These results for
the insulating state should be similar to those of the more general Hubbard
model. Also, the strong correlations suggest that even without any additional
broadening due to Auger like processes, the core-hole lifetime will be short.


  The dynamics of the reaction H + OH $\to$ O (3P) + H2 have been studied in a
series of quasi-classical trajectory (QCT) calculations and transition state
theory (TST) methods using high quality 3A' and 3A'' potential energy surfaces
(PESs). Accurate OH (v, j) state resolved cross sections and rate constants on
both potential energy surfaces are presented and fitted for OH at (v = 0, j =
0-16) and (v = 1, j = 0-6). The cross sections were calculated for different
collisional energies (Ec), ranging from the threshold energy at each specific
rovibrational state up to 1.0 eV with step sizes of 0.1 eV or less. They
increase steeply with collision energy when the barrier to reaction can be
overcome, after which the cross sections stay nearly constant with energy.
State resolved rate constants in the temperature range 200-2500 K are presented
based on the cross sections. Total thermal rate constants were calculated by
summing the rates for reaction on the 3A' and 3A'' potential energy surfaces
weighted by 1/3 and taking into account the thermal populations of the
rovibrational states of the OH molecules. It is shown that the improved
canonical variational transition (CVT) treatments with the approximation of
zero-curvature tunneling (ZCT) or small-curvature tunneling (SCT) produce
results more in accord with the QCT results than the TST and CVT methods. The
reactions are governed by the direct reaction mechanism. The rate constants for
OH in excited vibrational and rotational states are orders of magnitude larger
than the thermal rate constants, which needs to be taken into account in
astrochemical models.


  We propose using radio line spectroscopy to detect molecular absorption lines
(such as OH at 1.6-1.7 GHz) before and after the total eclipse of black widow
(BW) and other short orbital period binary pulsars with low mass companions.
The companion in such a binary may be ablated away by energetic particles and
high energy radiation produced by the pulsar wind. The observations will probe
the eclipsing wind being ablated by the pulsar and constrain the nature of the
companion and its surroundings. Maser emission from the interstellar medium
stimulated by a pulsar beam might also be detected from the intrabinary medium.
The short temporal resolution allowed by the millisecond pulsars can probe this
medium with the high angular resolution of the pulsar beam.


  This work proposes a new challenge set for multimodal classification,
focusing on detecting hate speech in multimodal memes. It is constructed such
that unimodal models struggle and only multimodal models can succeed: difficult
examples ("benign confounders") are added to the dataset to make it hard to
rely on unimodal signals. The task requires subtle reasoning, yet is
straightforward to evaluate as a binary classification problem. We provide
baseline performance numbers for unimodal models, as well as for multimodal
models with various degrees of sophistication. We find that state-of-the-art
methods perform poorly compared to humans (64.73% vs. 84.7% accuracy),
illustrating the difficulty of the task and highlighting the challenge that
this important problem poses to the community.


  General Relativity predicts that binary systems of stars produce
gravitational waves of significant intensity. Here we are particularly
interested in the cataclysmic variable binaries (CVs). These systems emit low
frequency gravitational waves, $ f < 10^{-3} Hz$. We present here a catalog of
CVs and argue that part of them are capable of being detected by the Laser
Interferometer Space Antenna (LISA).


  Tree-size distribution is one of the most investigated subjects in plant
population biology. The forestry literature reports that tree-size distribution
trajectories vary across different stands and/or species, while the metabolic
scaling theory suggests that the tree number scales universally as -2 power of
diameter. Here, we propose a simple functional scaling model in which these two
opposing results are reconciled. Basic principles related to crown shape,
energy optimization and the finite size scaling approach were used to define a
set of relationships based on a single parameter, which allows us to predict
the slope of the tree-size distributions in a steady state condition. We tested
the model predictions on four temperate mountain forests. Plots (4 ha each,
fully mapped) were selected with different degrees of human disturbance
(semi-natural stands vs. formerly managed). Results showed that the size
distribution range successfully fitted by the model is related to the degree of
forest disturbance: in semi-natural forests the range is wide, while in
formerly managed forests, the agreement with the model is confined to a very
restricted range. We argue that simple allometric relationships, at individual
level, shape the structure of the whole forest community.


  In this work, we approximate the surface photovoltage (SPV) transients in
nm-sized ZnO films by the equivalent RC circuit model. The SPV rises in time in
time for about 90 mcs after the exciting light pulse at 275 nm is off at
different pulse widths ranging from 1.2 to 12 mcs. The key to this observation
is a considerable amount of defects in the films, which form a trap capacitance
in the equivalent circuit. The photogeneration of nonequilibrium electrons and
holes near the film surface is described by charging of a capacitance by the
current source whereas the rate of their spatial separation is determined by a
resistance. This resistance reflects an obstacle in the carrier movement while
another capacitance determines the charge separation distance. The
electron-hole recombination is account for a second resistance introduced into
the equivalent circuit. The resulting modeled SPV transient allows to reproduce
the observed experimental curve rather well.


  It has been hypothesized that the sustained narrowness observed in the
asymptotic cylindrical region of bipolar outflows from Young Stellar Objects
(YSO) indicates that these jets are magnetically collimated. The j cross B
force observed in z-pinch plasmas is a possible explanation for these
observations. However, z-pinch plasmas are subject to current driven
instabilities (CDI). The interest in using z-pinches for controlled nuclear
fusion has lead to an extensive theory of the stability of magnetically
confined plasmas. Analytical, numerical, and experimental evidence from this
field suggest that sheared flow in magnetized plasmas can reduce the growth
rates of the sausage and kink instabilities. Here we propose the hypothesis
that sheared helical flow can exert a similar stabilizing influence on CDI in
YSO jets.


  Network Function Virtualization is considered one of the key technologies for
developing the future mobile networks. In this paper, we propose a theoretical
framework to evaluate the performance of an LTE virtualized Mobility Management
Entity (vMME) hosted in a data center. This theoretical framework consists of
i) a queuing network to model the vMME in a data center, and ii) analytic
expressions to estimate the overall mean system delay and the signaling
workload to be processed by the vMME. We validate our mathematical model by
simulation. One direct use of the proposed model is vMME dimensioning, i.e., to
compute the number of vMME processing instances to provide a target system
delay given the number of users in the system. Additionally, the paper includes
a scalability analysis of the system. In our study, we consider the billing
model and a data center setup of Amazon Elastic Compute Cloud service, and
estimate experimentally the processing time of MME processing instances for
different LTE control procedures. For the considered setup, our results show
that a vMME is scalable for signaling workloads up to 37000 LTE control
procedures per second for a target mean system delay of 1 ms. The database
performance assumed imposes this limit in the system scalability.


  Strong effect of beam coherent scattering ("reflection") in a field of bent
crystal is observed in crystal collimation experiments performed with heavy
ions and protons at RHIC and started at Tevatron collider. Detailed simulation
using Monte Carlo code CATCH is done in order to understand the observations
and relate them to the physics of beam coherent scattering in crystal. A.M.
Taratin and S.A. Vorobiev predicted the effect of beam "volume reflection" in
bent crystals in 1987. The presented data is the first manifestation of this
new physical phenomenon in experiment.


  We investigate the feasibility of quantum seals. A quantum seal is a state
provided by Alice to Bob along with information which Bob can use to make a
measurement, "break the seal," and read the classical message stored inside.
There are two success criteria for a seal: the probability Bob can successfully
read the message without any further information from Alice must be high, and
if Alice asks for the state back from Bob, the probability Alice can tell if
Bob broke the seal without permission must be high. We build on the work of
[Chau, PRA 2007], which gave optimal bounds on these criteria, showing that
they are mutually exclusive for high probability. We weaken the assumptions of
this previous work by providing Bob with only a classical description of a
prescribed measurement, rather than classical descriptions of the possible seal
states. We show that this weakening does not affect the bounds but does
simplify the analysis. We also prove upper and lower bounds on an alternative
operational metric for measuring the success criteria.