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The Dark Dimension and the Standard Model Landscape
We study the landscape of lower-dimensional vacua of the SM coupled to
gravity in the presence of the ``dark dimension'' of size in the
micron range, focusing on the validity of the swampland conjecture forbidding
the presence of non-SUSY AdS vacua in a consistent quantum gravity theory. We
first adopt the working assumption that right-handed neutrinos propagate in the
bulk, so that neutrino Yukawa couplings become tiny due to a volume
suppression, leading to naturally light Dirac neutrinos. We show that the
neutrino KK towers compensate for the graviton tower to maintain stable dS
vacua found in the past, but neutrino oscillation data set restrictive bounds
on and therefore the first KK neutrino mode is too heavy to alter the
shape of the radon potential or the required maximum mass for the lightest
neutrino to carry dS rather than AdS vacua found in the absence of the dark
dimension, . We also show that a very
light gravitino (with mass in the meV range) could help relax the neutrino mass
constraint . The differences for the
predicted total neutrino mass among these two scenarios are within
reach of next-generation cosmological probes that may measure the total
neutrino mass with an uncertainty . We
also demonstrate that the KK tower of a very light gravitino can compensate for
the graviton tower to sustain stable dS vacua and thus right-handed neutrinos
can (in principle) be locked on the brane. For this scenario, Majorana
neutrinos could develop dS vacua, which is not possible in the SM coupled to
gravity. Finally, we investigate the effects of bulk neutrino masses in
suppressing oscillations of the 0-modes into the first KK modes to relax the
oscillation bound on .Comment: Matching version to be published in PR
Domain-Invariant Proposals based on a Balanced Domain Classifier for Object Detection
Object recognition from images means to automatically find object(s) of
interest and to return their category and location information. Benefiting from
research on deep learning, like convolutional neural networks~(CNNs) and
generative adversarial networks, the performance in this field has been
improved significantly, especially when training and test data are drawn from
similar distributions. However, mismatching distributions, i.e., domain shifts,
lead to a significant performance drop. In this paper, we build
domain-invariant detectors by learning domain classifiers via adversarial
training. Based on the previous works that align image and instance level
features, we mitigate the domain shift further by introducing a domain
adaptation component at the region level within Faster \mbox{R-CNN}. We embed a
domain classification network in the region proposal network~(RPN) using
adversarial learning. The RPN can now generate accurate region proposals in
different domains by effectively aligning the features between them. To
mitigate the unstable convergence during the adversarial learning, we introduce
a balanced domain classifier as well as a network learning rate adjustment
strategy. We conduct comprehensive experiments using four standard datasets.
The results demonstrate the effectiveness and robustness of our object
detection approach in domain shift scenarios.Comment: fixed some issue
Tracking sustainability: co-evolution of economic and ecological activities in the industrialization of the United Kingdom and China
The co-evolution of economic and ecological activities represents one of the
fundamental challenges in the realm of sustainable development. This study on
the word trends in mainstream newspapers from the UK and China reveals that
both early-industrialised countries and latecomers follow three modes of
economic and ecological co-evolution. First, both economic and ecological words
demonstrate an S-shaped growth trajectory, and the mode underscores the
importance of information propagation, whilst also highlighting the crucial
role of self-organisation in the accept society. Second, the co-occurrence of
these two type words exhibits a Z-shaped relationship: for two-thirds of the
observed period, they display synergistic interactions, while the remaining
time shows trade-offs. Lastly, the words related to ecological degradation
follow M-shaped trajectories in parallel with economic growth, suggesting
periodic disruptions and reconstructions in their interrelationships. Our
findings contribute to a more nuanced understanding of the co-evolutionary
mechanisms that govern collective behaviours in human society
Overwhelmed software developers: An Interpretative Phenomenological Analysis
In this paper, we report on an Interpretive Phenomenological Analysis (IPA)
study on experiencing overwhelm in a software development context. The
objectives of our study are, hence, to understand the experiences developers
have when being overwhelmed, how this impacts their productivity and which role
stress plays in the process. To this end, we interviewed two software
developers who have experienced overwhelm recently. Throughout a qualitative
analysis of the shared experiences, we uncover seven categories of overwhelm
(communication, disturbance, organizational, variety, technical, temporal, and
positive overwhelm). While the first six themes all are related to negative
outcomes, including low productivity and stress, the participants reported that
overwhelm can sometimes be experienced to be positive and pleasant, and it can
increase their mental focus, self ambition, and productivity. Stress was the
most mentioned feeling experienced when overwhelmed. Our findings, for the
most, are along the same direction of similar studies from other disciplines
and with other participants. However, there may be unique attributes to
software developers that mitigate the negative experiences of overwhelm.Comment: 46 pages, technical repor
Sequential Monte Carlo Graph Convolutional Network for Dynamic Brain Connectivity
An increasingly important brain function analysis modality is functional
connectivity analysis which regards connections as statistical codependency
between the signals of different brain regions. Graph-based analysis of brain
connectivity provides a new way of exploring the association between brain
functional deficits and the structural disruption related to brain disorders,
but the current implementations have limited capability due to the assumptions
of noise-free data and stationary graph topology. We propose a new methodology
based on the particle filtering algorithm, with proven success in tracking
problems, which estimates the hidden states of a dynamic graph with only
partial and noisy observations, without the assumptions of stationarity on
connectivity. We enrich the particle filtering state equation with a graph
Neural Network called Sequential Monte Carlo Graph Convolutional Network
(SMC-GCN), which due to the nonlinear regression capability, can limit spurious
connections in the graph. Experiment studies demonstrate that SMC-GCN achieves
the superior performance of several methods in brain disorder classification
Equivariant localization and holography
We discuss the theory of equivariant localization focussing on applications
relevant for holography. We consider geometries comprising compact and
non-compact toric orbifolds, as well as more general non-compact toric
Calabi-Yau singularities. A key object in our constructions is the equivariant
volume, for which we describe two methods of evaluation: the Berline-Vergne
fixed-point formula and the Molien-Weyl formula, supplemented by the
Jeffrey-Kirwan prescription. We present two applications in supersymmetric
field theories. Firstly, we describe a method for integrating the anomaly
polynomial of SCFTs on compact toric orbifolds. Secondly, we discuss
equivariant orbifold indices that are expected to play a key role in the
computation of supersymmetric partition functions. In the context of
supergravity, we propose that the equivariant volume can be used to
characterise universally the geometry of a large class of supersymmetric
solutions. As an illustration, we employ equivariant localization to prove the
factorization in gravitational blocks of various supergravity free energies,
recovering previous results as well as obtaining generalizations.Comment: 69 pages, 10 figures; published version, few typos correcte
Combining Matrix Product States and Noisy Quantum Computers for Quantum Simulation
Matrix Product States (MPS) and Operators (MPO) have been proven to be a
powerful tool to study quantum many-body systems but are restricted to
moderately entangled states as the number of parameters scales exponentially
with the entanglement entropy. While MPS can efficiently find ground states of
1D systems, their capacities are limited when simulating their dynamics, where
the entanglement can increase ballistically with time. On the other hand,
quantum devices appear as a natural platform to encode and perform the time
evolution of correlated many-body states. However, accessing the regime of
long-time dynamics is hampered by quantum noise. In this study we use the best
of worlds: the short-time dynamics is efficiently performed by MPSs, compiled
into short-depth quantum circuits, and is performed further in time on a
quantum computer thanks to efficient MPO-optimized quantum circuits. We
quantify the capacities of this hybrid classical-quantum scheme in terms of
fidelities taking into account a noise model. We show that using classical
knowledge in the form of tensor networks provides a way to better use limited
quantum resources and lowers drastically the noise requirements to reach a
practical quantum advantage. Finally we successfully demonstrate our approach
with an experimental realization of the technique. Combined with efficient
circuit transpilation we simulate a 10-qubit system on an actual quantum device
over a longer time scale than low-bond-dimension MPSs and purely quantum
Trotter evolution
Histopathology Slide Indexing and Search: Are We There Yet?
The search and retrieval of digital histopathology slides is an important
task that has yet to be solved. In this case study, we investigate the clinical
readiness of three state-of-the-art histopathology slide search engines,
Yottixel, SISH, and RetCCL, on three patients with solid tumors. We provide a
qualitative assessment of each model's performance in providing retrieval
results that are reliable and useful to pathologists. We found that all three
image search engines fail to produce consistently reliable results and have
difficulties in capturing granular and subtle features of malignancy, limiting
their diagnostic accuracy. Based on our findings, we also propose a minimal set
of requirements to further advance the development of accurate and reliable
histopathology image search engines for successful clinical adoption
Track Lab: extensible data acquisition software for fast pixel detectors, online analysis and automation
Fast, incremental evolution of physics instrumentation raises the question of
efficient software abstraction and transferability of algorithms across similar
technologies. This contribution aims to provide an answer by introducing Track
Lab, a modern data acquisition program focusing on extensibility and high
performance. Shipping with documented API and more than 20 standard modules,
Track Lab allows complex analysis pipelines to be constructed from simple,
reusable building blocks. Thanks to multi-threaded infrastructure, data can be
clustered, filtered, aggregated and plotted concurrently in real-time. In
addition, full hardware support for Timepix2, Timepix3 pixel detectors and
embedded photomultiplier systems enables such analysis to be carried out online
during data acquisition. Repetitive procedures can be automated with support
for motorized stages and X-ray tubes. Freely distributed on 7 popular operating
systems and 2 CPU architectures, Track Lab is a versatile tool for high energy
physics research.Comment: Proceedings of the 24th International Workshop on Radiation Imaging
Detectors (IWORID 2023
Parabolic frequency monotonicity on the conformal Ricci flow
This paper is devoted to the investigation of the monotonicity of parabolic
frequency functional under conformal Ricci flow defined on a closed Riemannian
manifold of constant scalar curvature and dimension not less than 3. Parabolic
frequency functional for solutions of certain linear heat equation coupled with
conformal pressure is defined and its monotonicity under the conformal Ricci
flow is proved by applying Bakry-Emery Ricci curvature bounds. Some
consequences of the monotonicity are also presented.Comment: 18 page