cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Chandra X-ray Observatory Observations of 13 Fermi LAT Sources
Creators: name: Rangelov, Blagoy
name: Yang, Hui
name: Williams, Brice
name: Kargaltsev, Oleg
name: Hare, Jeremy
name: Martinic, Kean
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In the latest data release from the Fermi $γ$-ray Space Telescope (the 4th Fermi LAT 14 yr Catalog, or 4FGL), more than 50% of the Galactic sources are yet to be identified. We observed 13 unidentified Fermi LAT sources with the Chandra X-Ray Observatory to explore their nature. We report the results of the classification of X-ray sources in the fields of these $γ$-ray sources and discuss the implications for their nature. We use multiwavelength (MW) data for a machine-learning classification, accompanied by a more detailed spectral/variability analysis for brighter sources. Eight 4FGL sources have $γ$-ray pulsars within their position error ellipses. We consider three of these pulsars (PSR J1906+0722, PSR J1105-6037, and PSR J1358-6025) to be detected in X-rays, while PSR J1203-6242 shows a hint of X-ray emission. Within the positional uncertainties of three of the 4FGL sources, we detect X-ray sources that may be yet unknown pulsars, depending on the MW association. In addition to point sources, we discovered two extended sources, one of which is likely to be a bow-shock pulsar-wind nebula associated with PSR J1358-6025. Finally, we classify other X-ray sources detected in these observations and report the most interesting classifications.
description: Published in ApJ 961, 26 (2024). 16 pages, 4 figures, 5 tables
Challenges in Domain-Specific Abstractive Summarization and How to Overcome them
Creators: name: Afzal, Anum
name: Vladika, Juraj
name: Braun, Daniel
name: Matthes, Florian
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Large Language Models work quite well with general-purpose data and many tasks in Natural Language Processing. However, they show several limitations when used for a task such as domain-specific abstractive text summarization. This paper identifies three of those limitations as research problems in the context of abstractive text summarization: 1) Quadratic complexity of transformer-based models with respect to the input text length; 2) Model Hallucination, which is a model's ability to generate factually incorrect text; and 3) Domain Shift, which happens when the distribution of the model's training and test corpus is not the same. Along with a discussion of the open research questions, this paper also provides an assessment of existing state-of-the-art techniques relevant to domain-specific text summarization to address the research gaps.
Uncertainties in constraining low-energy constants from $^3$H $β$ decay
Creators: name: Klos, P.
name: Carbone, A.
name: Hebeler, K.
name: Menéndez, J.
name: Schwenk, A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We discuss the uncertainties in constraining low-energy constants of chiral effective field theory from $^3$H $β$ decay. The half-life is very precisely known, so that the Gamow-Teller matrix element has been used to fit the coupling $c_D$ of the axial-vector current to a short-range two-nucleon pair. Because the same coupling also describes the leading one-pion-exchange three-nucleon force, this in principle provides a very constraining fit, uncorrelated with the $^3$H binding energy fit used to constrain another low-energy coupling in three-nucleon forces. However, so far such $^3$H half-life fits have only been performed at a fixed cutoff value. We show that the cutoff dependence due to the regulators in the axial-vector two-body current can significantly affect the Gamow-Teller matrix elements and consequently also the extracted values for the $c_D$ coupling constant. The degree of the cutoff dependence is correlated with the softness of the employed NN interaction. As a result, present three-nucleon forces based on a fit to $^3$H $β$ decay underestimate the uncertainty in $c_D$. We explore a range of $c_D$ values that is compatible within cutoff variation with the experimental $^3$H half-life and estimate the resulting uncertainties for many-body systems by performing calculations of symmetric nuclear matter.
description: 9 pages, 11 figures, published version, includes Erratum, which corrects Figs. 2-6 due to the incorrect c_D relation between 3N forces and two-body currents used
Outcome analysis on individual health budgets in mental Health: finding from the Friuli Venezia Giulia Region, Italy
Creators: name: Fontecedro, Elisa
name: Tossut, Davide
name: Scattoni, Maria Luisa
name: Micai, Martina
name: Bonavigo, Tommaso
name: Salvador-Carulla, Luis
name: D’Avanzo, Barbara
name: Furlan, Morena
name: Castelpietra, Giulio
Publisher: name: Taylor & Francis
Year: 2025
Subjects: subject: Medicine
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Science Policy
subject: Mental Health
subject: Computational Biology

description: Individual Health Budget (IHB) is used for social and health integration and to facilitate processes of resource reorientation in healthcare. Despite its increased use in mental health settings, few studies investigated its effectiveness in severe mental disorders. 383 IHB beneficiaries were recruited among Mental Health Departments users of the Italian region Friuli Venezia Giulia. Data involved sociodemographic and clinical variables, IHB type and scores of Health of the Nation Outcome Scale (HoNOS) at admission to IHB programme (T0), after 12 months (T1), and after 24 months (T2). The length and the mean number of hospitalisations and healthcare interventions decreased at T1. A significant scores’ reduction from T0 to T1 evaluation was found in HoNOS total score (T-test (P) < 0.05) and in most of its items. An improvement throughout the whole evaluation period (T0 vs. T2) was found in 36% of the IHB beneficiaries, while more than 60% of them remained in the same HoNOS severity category. Our results support the use of IHB in patients with severe mental problems, since it may contribute to an improvement in social and clinical functioning, consequently lowering the burden on MHDs.
Interaction-driven (quasi-) insulating ground states of gapped electron-doped bilayer graphene
Creators: name: Seiler, Anna M.
name: Statz, Martin
name: Weimer, Isabell
name: Jacobsen, Nils
name: Watanabe, Kenji
name: Taniguchi, Takashi
name: Dong, Zhiyu
name: Levitov, Leonid S.
name: Weitz, R. Thomas
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Bernal bilayer graphene has recently been discovered to exhibit a wide range of unique ordered phases resulting from interaction-driven effects and encompassing spin and valley magnetism, correlated insulators, correlated metals, and superconductivity. This letter reports on a novel family of correlated phases characterized by spin and valley ordering, observed in electron-doped bilayer graphene. The novel correlated phases demonstrate an intriguing non-linear current-bias behavior at ultralow currents that is sensitive to the onset of the phases and is accompanied by an insulating temperature dependence, providing strong evidence for the presence of unconventional charge carrying degrees of freedom originating from ordering. These characteristics cannot be solely attributed to any of the previously reported phases, and are qualitatively different from the behavior seen previously on the hole-doped side. Instead, our observations align with the presence of charge- or spin-density-waves state that open a gap on a portion of the Fermi surface or fully gapped Wigner crystals. The resulting new phases, quasi-insulators in which part of the Fermi surface remains intact or valley-polarized and valley-unpolarized Wigner crystals, coexist with previously known Stoner phases, resulting in an exceptionally intricate phase diagram.
Applied AI/ML for automatic customisation of medical implants
Creators: name: Burge, Thomas Alexander
Publisher: name: Imperial College London
Year: 2023

description: Most knee replacement surgeries are performed using ‘off-the-shelf’ implants, supplied with a set number of standardised sizes. X-rays are taken during pre-operative assessment and used by clinicians to estimate the best options for patients. Manual templating and implant size selection have, however, been shown to be inaccurate, and frequently the generically shaped products do not adequately fit patients’ unique anatomies. Furthermore, off-the-shelf implants are typically made from solid metal and do not exhibit mechanical properties like the native bone. Consequently, the combination of these factors often leads to poor outcomes for patients. Various solutions have been outlined in the literature for customising the size, shape, and stiffness of implants for the specific needs of individuals. Such designs can be fabricated via additive manufacturing which enables bespoke and intricate geometries to be produced in biocompatible materials. Despite this, all customisation solutions identified required some level of manual input to segment image files, identify anatomical features, and/or drive design software. These tasks are time consuming, expensive, and require trained resource. Almost all currently available solutions also require CT imaging, which adds further expense, incurs high levels of potentially harmful radiation, and is not as commonly accessible as X-ray imaging. This thesis explores how various levels of knee replacement customisation can be completed automatically by applying artificial intelligence, machine learning and statistical methods. The principal output is a software application, believed to be the first true ‘mass-customisation’ solution. The software is compatible with both 2D X-ray and 3D CT data and enables fully automatic and accurate implant size prediction, shape customisation and stiffness matching. It is therefore seen to address the key limitations associated with current implant customisation solutions and will hopefully enable the benefits of customisation to be more widely accessible.
Curved spacetimes with local $κ$-Poincaré dispersion relation
Creators: name: Barcaroli, Leonardo
name: Brunkhorst, Lukas K.
name: Gubitosi, Giulia
name: Loret, Niccoló
name: Pfeifer, Christian
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We use our previously developed identification of dispersion relations with Hamilton functions on phase space to locally implement the $κ$-Poincaré dispersion relation in the momentum spaces at each point of a generic curved spacetime. We use this general construction to build the most general Hamiltonian compatible with spherical symmetry and the Plank-scale-deformed one such that in the local frame it reproduces the $κ$-Poincaré dispersion relation. Specializing to Planck-scale-deformed Schwarzschild geometry, we find that the photon sphere around a black hole becomes a thick shell since photons of different energy will orbit the black hole on circular orbits at different altitudes. We also compute the redshift of a photon between different observers at rest, finding that there is a Planck-scale correction to the usual redshift only if the observers detecting the photon have different masses.
description: 28 pages, updated to accepted journal version, appendix on kappa-Poincare electrodynamics added
Outcome analysis on individual health budgets in mental Health: finding from the Friuli Venezia Giulia Region, Italy
Creators: name: Elisa, Fontecedro
name: Davide, Tossut
name: Luisa, Scattoni Maria
name: Martina, Micai
name: Tommaso, Bonavigo
name: Luis, Salvador-Carulla
name: Barbara, D’Avanzo
name: Morena, Furlan
name: Giulio, Castelpietra
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Biotechnology
subject: Sociology
subject: FOS: Sociology
subject: Science Policy
subject: Mental Health
subject: Computational Biology

description: Individual Health Budget (IHB) is used for social and health integration and to facilitate processes of resource reorientation in healthcare. Despite its increased use in mental health settings, few studies investigated its effectiveness in severe mental disorders. 383 IHB beneficiaries were recruited among Mental Health Departments users of the Italian region Friuli Venezia Giulia. Data involved sociodemographic and clinical variables, IHB type and scores of Health of the Nation Outcome Scale (HoNOS) at admission to IHB programme (T0), after 12 months (T1), and after 24 months (T2). The length and the mean number of hospitalisations and healthcare interventions decreased at T1. A significant scores’ reduction from T0 to T1 evaluation was found in HoNOS total score (T-test (P) < 0.05) and in most of its items. An improvement throughout the whole evaluation period (T0 vs. T2) was found in 36% of the IHB beneficiaries, while more than 60% of them remained in the same HoNOS severity category. Our results support the use of IHB in patients with severe mental problems, since it may contribute to an improvement in social and clinical functioning, consequently lowering the burden on MHDs.
Ambiguous measurements, signalling and violations of Leggett-Garg inequalities
Creators: name: Emary, Clive
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Ambiguous measurements do not reveal complete information about the system under test. Their quantum-mechanical counterparts are semi-weak (or in the limit, weak-) measurements and here we discuss their role in tests of the Leggett-Garg inequalities. We show that, whilst ambiguous measurements allow one to forgo the usual non-invasive measureability assumption, to derive an LGI that may be violated, we are forced to introduce another assumption that equates the invasive influence of ambiguous and unambiguous detectors. Based on this assumption, we derive signalling conditions that should be fulfilled for the plausibility of the Leggett-Garg test. We then propose an experiment on a three-level system with a direct quantum-optics realisation that satisfies all signalling constraints and violates a Leggett-Garg inequality.
description: 9 pages; 4 figures
Gauge-invariant approach to the beta function in Yang-Mills theories with universal extra dimensions
Creators: name: Huerta-Leal, M.
name: Novales-Sánchez, H.
name: Toscano, J. J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The radiative correction to beta function is comprehensively studied at 1 loop in the context of universal extra dimensions. Instead of using cutoffs to regularize 1-loop divergences, the dimensional regularization scheme is used. Large momenta effects are removed from physical amplitudes by adjusting the parameters of the appropriate counterterms. The use of a SU(N)-covariant gauge-fixing procedure is stressed. 1-loop contributions of KK excitations are characterized by discrete KK sums and continuous momenta sums, which can diverge. Two types of UVs are identified, one arising from poles of the gamma function and associated with short-distance effects in the usual 4-dimensional spacetime manifold, and the other emerging either from poles of the 1-dimensional Epstein function or from the gamma function, and corresponding to short-distance effects in the compact manifold. We address the cases of 5 and 4+n dimensions (n>1) separately. In 5 dimensions the 1-dimensional Epstein function is convergent, so the usual counterterm renormalizes the vacuum polarization function. For 4+n dimensions, the 1-dimensional Epstein function is divergent, so renormalization is implemented by interactions of canonical dimension higher than 4, already present in the effective theory. The polarization function is renormalized using both mass-dependent and mass-independent schemes, with extra-dimensions effects decoupling in the former case but not in the latter. The beta function is calculated for an arbitrary number of extra dimensions. Our main result is that Yang-Mills theory remains perturbative at 1 loop, which is in disagreement with the results obtained in the literature by using a cutoff regulator, which suggest that Yang-Mills theory in more than 4 dimensions ceases to be perturbative. We emphasize the advantages of a mass-dependent scheme in this type of theories, in which decoupling is manifest.
description: 30 pages
Standardized Interpretable Fairness Measures for Continuous Risk Scores
Creators: name: Becker, Ann-Kristin
name: Dumitrasc, Oana
name: Broelemann, Klaus
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (stat.ML)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We propose a standardized version of fairness measures for continuous scores with a reasonable interpretation based on the Wasserstein distance. Our measures are easily computable and well suited for quantifying and interpreting the strength of group disparities as well as for comparing biases across different models, datasets, or time points. We derive a link between the different families of existing fairness measures for scores and show that the proposed standardized fairness measures outperform ROC-based fairness measures because they are more explicit and can quantify significant biases that ROC-based fairness measures miss.
New Land Managers: opportunities for delivering public goods through collaborative conservation
Creators: name: Kam, Hermann Jun Wei
Publisher: name: Imperial College London
Year: 2023

description: A shift in the scale and ambition of a new suite of agri-environmental policies in the UK, towards delivering public goods on a landscape scale, is occurring in the midst of changing land occupancy patterns in the countryside. The central contention of this thesis is that the emergence of ‘new land managers’ – many of whom appear equally well-placed as main occupation farmers to deliver public goods – needs to be seized as an opportunity by policymakers for promoting more collaborative and landscape scale conservation. The challenge thus lies in the ability of future schemes to recruit a broader range of landholders than, at present, into these collaborations. However, the make-up and motivations of these new land managers remains poorly understood, following decades long hiatus in research investigating structural changes in agriculture. In this thesis, we first draw on a survey and key-informant interviews with land agents to better understand the trends and drivers shaping the rural land market and the characteristics of what we term “new land managers”. The work proceeds to establish various models of collaboration, drawing on outputs from the Q-methodology conducted with land managers themselves, to assess how an increasingly diverse land management community might in future be engaged with and can work together in collaboration. Our findings suggest a continued restructuring of the agriculture industry, and the countryside overall, due to longstanding pressures and the implications of the shifting agriculture policy agenda. The result is a growing heterogeneity of landholder groups managing land in increasingly diverse ways and have values and motivations that are different to farmers. Our various models of collaboration also point to a need for future policies to think more directly about how this diversifying land management community might be grouped, and incentivised, into collaborative conservation according to their perspectives. We conclude that policymakers would need to deliver a suite of interventions specifically tailored to the various types of landholders to ensure an effective, and collaborative, delivery of public goods under the new Environmental Land Management schemes.
title: EDUCATION AIMED TO INCREASE TRAIN-OF-FOUR RATIO USE
Creators: name: Bougher, Frank
Publisher: name: Digital Commons@Becker, Barnes Jewish College Goldfarb School of Nursing
Year: 2023
Subjects: classificationCode: 3
subject: FOS: Medical and health sciences

description: Background and Review of Literature: The current state of practice surrounding non-depolarizing neuromuscular blocking drug monitoring is variable among practitioners and poses a safety risk to patients who may subsequently experience residual neuromuscular blockade and complications. The literature supports that train-of-four ratio monitoring, with an emphasis on use prior to extubation, is superior to other techniques and reduces the occurrence of complications related to residual neuromuscular blockade, improving patient safety and outcomes.
Purpose: The purpose of the project was to determine if an education intervention founded on evidence-based neuromuscular monitoring leads to increased use of train-of-four ratio in practitioner practice as well as improved knowledge and confidence in monitoring techniques.
Methods: A pre-intervention-post-intervention design was conducted with an educational intervention in participants from a local anesthesia group in the metropolitan St. Louis area. Retrospective electronic health record extraction was used to assess train-of-four ratio rate of use.
Implementation Plan/Procedure: A pre-recorded asynchronous powerpoint lecture was presented as the educational intervention. Word document surveys were emailed to participants the week immediately prior to education, the week immediately following intervention, thirty-day and sixty-day post-intervention to assess impact.
Implications/Conclusion: Study participants gained new knowledge evidenced by survey mean scores pre-intervention vs. post-intervention. There was not an increase in train-of-four ratio monitoring rate according to the electronic health record data. A pre-recorded education is a practical way to present evidence-based education to increase knowledge of neuromuscular monitoring among practitioners.
Difference between charge-voltage relations of ordinary and fractional capacitors
Creators: name: Marthins, Eirik Brenner
name: Holm, Sverre
Publisher: name: arXiv
Year: 2023
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: In an ordinary time-varying capacitor, there is debate whether a time-domain multiplication or a time-domain convolution of capacitance and voltage determines charge. A time-varying capacitor in parallel with a resistor was implemented by a motor-driven potentiometer and op-amps. The response matched a power-law function over about two decades of time, and not an exponential, for several sets of parameters. This confirms the time-domain multiplication model. This result is the opposite of that obtained for a Constant Phase Element (CPE) in its common time- and frequency-varying capacitor interpretation. This demonstrates that a CPE is fundamentally different from an ordinary time- and frequency-varying capacitor.
description: 13 pages, 6 figures
An embedding theorem for tangent categories
Creators: name: Garner, Richard
Publisher: name: arXiv
Year: 2017
Subjects: subject: Category Theory (math.CT)
subject: FOS: Mathematics

description: Tangent categories were introduced by Rosicky as a categorical setting for differential structures in algebra and geometry; in recent work of Cockett, Crutwell and others, they have also been applied to the study of differential structure in computer science. In this paper, we prove that every tangent category admits an embedding into a representable tangent category---one whose tangent structure is given by exponentiating by a free-standing tangent vector, as in, for example, any model of Kock and Lawvere's synthetic differential geometry. The key step in our proof uses a coherence theorem for tangent categories due to Leung to exhibit tangent categories as a certain kind of enriched category.
description: 17 pages. v3: final journal version
A lambda calculus for density matrices with classical and probabilistic controls
Creators: name: Díaz-Caro, Alejandro
Publisher: name: arXiv
Year: 2017
Subjects: subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences

description: In this paper we present two flavors of a quantum extension to the lambda calculus. The first one, $λ_ρ$, follows the approach of classical control/quantum data, where the quantum data is represented by density matrices. We provide an interpretation for programs as density matrices and functions upon them. The second one, $λ_ρ^\circ$, take advantage of the density matrices presentation in order to follow the mixed trace of programs in a kind of generalised density matrix. Such a control can be seen as a weaker form of the quantum control and data approach.
description: This version includes a 11-pages appendix with proofs, and a small fix in the definition of property P(b,A)
Entanglement dynamics in $κ$-deformed spacetime
Creators: name: Liu, Xiaobao
name: Tian, Zehua
name: Jing, Jiliang
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We treat two identical and mutually independent two-level atoms that are coupled to a quantum field as an open quantum system. The master equation that governs their evolution is derived by tracing over the degree of freedom of the field. With this, we compare the entanglement dynamics of the two atoms moving with different trajectories in $κ$-deformed and Minkowski spacetimes. Notably, when the environment-induced interatomic interaction does not exist, the entanglement dynamics of two static atoms in $κ$-deformed spacetime are reduced to that in Minkowski spacetime in the case that the spacetime deformation parameter $κ$ is sufficiently large as theoretically predicted. However, if the atoms undergo relativistic motion, regardless of whether inertial or non-inertial, their entanglement dynamics in $κ$-deformed spacetime behave differently from that in Minkowski spacetime even when $κ$ is large. We investigate various types of entanglement behavior, such as decay and generation, and discuss how different relativistic motions, such as uniform motion in a straight line and circular motion, amplify the differences in the entanglement dynamics between the $κ$-deformed and Minkowski spacetime cases. In addition, when the environment-induced interatomic interaction is considered, we find that it may also enhance the differences in the entanglement dynamics between these two spacetimes. Thus, in principle, one can tell whether she/he is in $κ$-deformed or Minkowski spacetime by checking the entanglement behavior between two atoms in certain circumstances.
description: 41 pages, 16 figures
Interconnectedness in the Global Financial Market
Creators: name: Raddant, Matthias
name: Kenett, Dror Y.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Statistical Finance (q-fin.ST)
subject: General Economics (econ.GN)
subject: General Finance (q-fin.GN)
subject: FOS: Economics and business

description: The global financial system is highly complex, with cross-border interconnections and interdependencies. In this highly interconnected environment, local financial shocks and events can be easily amplified and turned into global events. This paper analyzes the dependencies among nearly 4,000 stocks from 15 countries. The returns are normalized by the estimated volatility using a GARCH model and a robust regression process estimates pairwise statistical relationships between stocks from different markets. The estimation results are used as a measure of statistical interconnectedness, and to derive network representations, both by country and by sector. The results show that countries like the United States and Germany are in the core of the global stock market. The energy, materials, and financial sectors play an important role in connecting markets, and this role has increased over time for the energy and materials sectors. Our results confirm the role of global sectoral factors in stock market dependence. Moreover, our results show that the dependencies are rather volatile and that heterogeneity among stocks is a non-negligible aspect of this volatility.
Novel methods for multi-view learning with applications in cyber security
Creators: name: Hogan, Jack
Publisher: name: Imperial College London
Year: 2023

description: Modern data is complex. It exists in many different forms, shapes and kinds. Vectors, graphs, histograms, sets, intervals, etc.: they each have distinct and varied structural properties. Tailoring models to the characteristics of various feature representations has been the subject of considerable research. In this thesis, we address the challenge of learning from data that is described by multiple heterogeneous feature representations. This situation arises often in cyber security contexts. Data from a computer network can be represented by a graph of user authentications, a time series of network traffic, a tree of process events, etc. Each representation provides a complementary view of the holistic state of the network, and so data of this type is referred to as multi-view data. Our motivating problem in cyber security is anomaly detection: identifying unusual observations in a joint feature space, which may not appear anomalous marginally. Our contributions include the development of novel supervised and unsupervised methods, which are applicable not only to cyber security but to multi-view data in general. We extend the generalised linear model to operate in a vector-valued reproducing kernel Hilbert space implied by an operator-valued kernel function, which can be tailored to the structural characteristics of multiple views of data. This is a highly flexible algorithm, able to predict a wide variety of response types. A distinguishing feature is the ability to simultaneously identify outlier observations with respect to the fitted model. Our proposed unsupervised learning model extends multidimensional scaling to directly map multi-view data into a shared latent space. This vector embedding captures both commonalities and disparities that exist between multiple views of the data. Throughout the thesis, we demonstrate our models using real-world cyber security datasets.
OmniLRS: A Photorealistic Simulator for Lunar Robotics
Creators: name: Richard, Antoine
name: Kamohara, Junnosuke
name: Uno, Kentaro
name: Santra, Shreya
name: van der Meer, Dave
name: Olivares-Mendez, Miguel
name: Yoshida, Kazuya
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Developing algorithms for extra-terrestrial robotic exploration has always been challenging. Along with the complexity associated with these environments, one of the main issues remains the evaluation of said algorithms. With the regained interest in lunar exploration, there is also a demand for quality simulators that will enable the development of lunar robots. % In this paper, we explain how we built a Lunar simulator based on Isaac Sim, Nvidia's robotic simulator. In this paper, we propose Omniverse Lunar Robotic-Sim (OmniLRS) that is a photorealistic Lunar simulator based on Nvidia's robotic simulator. This simulation provides fast procedural environment generation, multi-robot capabilities, along with synthetic data pipeline for machine-learning applications. It comes with ROS1 and ROS2 bindings to control not only the robots, but also the environments. This work also performs sim-to-real rock instance segmentation to show the effectiveness of our simulator for image-based perception. Trained on our synthetic data, a yolov8 model achieves performance close to a model trained on real-world data, with 5% performance gap. When finetuned with real data, the model achieves 14% higher average precision than the model trained on real-world data, demonstrating our simulator's photorealism.% to realize sim-to-real. The code is fully open-source, accessible here: https://github.com/AntoineRichard/LunarSim, and comes with demonstrations.
description: 7 pages, 4 figures
Double Coupled Canonical Polyadic Decomposition for Joint Blind Source Separation
Creators: name: Gong, Xiao-Feng
name: Lin, Qiu-Hua
name: Cong, Feng-Yu
name: De Lathauwer, Lieven
Publisher: name: arXiv
Year: 2016
Subjects: subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Joint blind source separation (J-BSS) is an emerging data-driven technique for multi-set data-fusion. In this paper, J-BSS is addressed from a tensorial perspective. We show how, by using second-order multi-set statistics in J-BSS, a specific double coupled canonical polyadic decomposition (DC-CPD) problem can be formulated. We propose an algebraic DC-CPD algorithm based on a coupled rank-1 detection mapping. This algorithm converts a possibly underdetermined DC-CPD to a set of overdetermined CPDs. The latter can be solved algebraically via a generalized eigenvalue decomposition based scheme. Therefore, this algorithm is deterministic and returns the exact solution in the noiseless case. In the noisy case, it can be used to effectively initialize optimization based DC-CPD algorithms. In addition, we obtain the determini- stic and generic uniqueness conditions for DC-CPD, which are shown to be more relaxed than their CPD counterpart. Experiment results are given to illustrate the superiority of DC-CPD over standard CPD based BSS methods and several existing J-BSS methods, with regards to uniqueness and accuracy.
description: Accepted by IEEE Transactions on Signal Processing
Strong coupling of microwave photons to antiferromagnetic fluctuations in an organic magnet
Creators: name: Mergenthaler, M.
name: Liu, J.
name: Roy, J. J. Le
name: Ares, N.
name: Thompson, A. L.
name: Bogani, L.
name: Luis, F.
name: Blundell, S. J.
name: Lancaster, T.
name: Ardavan, A.
name: Briggs, G. A. D.
name: Leek, P. J.
name: Laird, E. A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Coupling between a crystal of di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium radicals and a superconducting microwave resonator is investigated in a circuit quantum electrodynamics (circuit QED) architecture. The crystal exhibits paramagnetic behavior above 4~K, with antiferromagnetic correlations appearing below this temperature, and we demonstrate strong coupling at base temperature. The magnetic resonance acquires a field angle dependence as the crystal is cooled down, indicating anisotropy of the exchange interactions. These results show that multispin modes in organic crystals are suitable for circuit QED, offering a platform for their coherent manipulation. They also utilize the circuit QED architecture as a way to probe spin correlations at low temperature.
Consistency of scalar and vector effective field theories
Creators: name: Pozsgay, Victor Matyas
Publisher: name: Imperial College London
Year: 2023

description: In the absence of a theory of everything, modern physicists need to rely on other predictive tools and turned to Effective Field Theories (EFTs) in a number of fields, including but not limited to statistical mechanics, condensed matter, particle physics, cosmology and gravity. The coefficients of an EFT can be constrained with high precision by experiments, which can involve high-energy particle colliders for instance but are generally left free from the theoretical point of view. The focus of this thesis is to use various consistency criteria to get theoretical constraints on the low-energy coefficients of EFTs. In particular, we construct a new model of massive spin-1 field by requiring that the theory is free of any ghostly degree of freedom. We then study its cosmological perturbations and ask that all propagating modes are stable and subluminal, reducing the space of viable cosmological solutions. Finally, we implement a method to get ‘causality bounds’, which are obtained by requiring infrared causality. This is imposed by forbidding any resolvable time advance in the EFT. We derive such ‘causality bounds’ for shift-symmetric and Galileon scalar EFTs, before turning to gauge-symmetric vector fields. We prove that our causality bounds can be competitive with positivity bounds and can even be used in scenarios that are out of reach of the positivity approach. The result of this thesis, by exploring several consistency criteria, is to provide compact causality bounds for low-energy EFT coefficients, in addition to constraints coming from the absence of ghosts, stability and cosmological viability.
On the generic part of the cohomology of non-compact PEL-type A Shimura varieties
Creators: name: Milheiro Marques Da Silva Santos, Mafalda
Publisher: name: Imperial College London
Year: 2023

description: In this thesis, we use the new methods of Koshikawa to prove that the generic l-adic cohomology of non-compact type A Shimura varieties vanishes below middle degree, when localized at a maximal ideal of the Hecke algebra. This generalizes previously established vanishing results of Caraiani-Scholze.
A unique van Hove singularity in kagome superconductor CsV$_{3-x}$Ta$_x$Sb$_5$ with enhanced superconductivity
Creators: name: Luo, Yang
name: Han, Yulei
name: Liu, Jinjin
name: Chen, Hui
name: Huang, Zihao
name: Huai, Linwei
name: Li, Hongyu
name: Wang, Bingqian
name: Shen, Jianchang
name: Ding, Shuhan
name: Li, Zeyu
name: Peng, Shuting
name: Wei, Zhiyuan
name: Miao, Yu
name: Sun, Xiupeng
name: Ou, Zhipeng
name: Xiang, Ziji
name: Hashimoto, Makoto
name: Lu, Donghui
name: Yao, Yugui
name: Yang, Haitao
name: Chen, Xianhui
name: Gao, Hong-Jun
name: Qiao, Zhenhua
name: Wang, Zhiwei
name: He, Junfeng
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Van Hove singularity (VHS) has been considered as a driving source for unconventional superconductivity. A VHS in two-dimensional (2D) materials consists of a saddle point connecting electron-like and hole-like bands. In a rare case, when a VHS appears at Fermi level, both electron-like and hole-like conduction can coexist, giving rise to an enhanced density of states as well as an attractive component of Coulomb interaction for unconventional electronic pairing. However, this van Hove scenario is often destroyed by an incorrect chemical potential or competing instabilities. Here, by using angle-resolved photoemission measurements, we report the observation of a VHS perfectly aligned with the Fermi level in a kagome superconductor CsV$_{3-x}$Ta$_x$Sb$_5$ (x~0.4), in which a record-high superconducting transition temperature is achieved among all the current variants of AV$_3$Sb$_5$ (A=Cs, Rb, K) at ambient pressure. Doping dependent measurements reveal the important role of van Hove scenario in boosting superconductivity, and spectroscopic-imaging scanning tunneling microscopy measurements indicate a distinct superconducting state in this system.
description: 20 pages, 4 figures
The ZX calculus is a language for surface code lattice surgery
Creators: name: de Beaudrap, Niel
name: Horsman, Dominic
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Logic in Computer Science (cs.LO)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: A leading choice of error correction for scalable quantum computing is the surface code with lattice surgery. The basic lattice surgery operations, the merging and splitting of logical qubits, act non-unitarily on the logical states and are not easily captured by standard circuit notation. This raises the question of how best to design, verify, and optimise protocols that use lattice surgery, in particular in architectures with complex resource management issues. In this paper we demonstrate that the operations of the ZX calculus -- a form of quantum diagrammatic reasoning based on bialgebras -- match exactly the operations of lattice surgery. Red and green "spider" nodes match rough and smooth merges and splits, and follow the axioms of a dagger special associative Frobenius algebra. Some lattice surgery operations require non-trivial correction operations, which are captured natively in the use of the ZX calculus in the form of ensembles of diagrams. We give a first taste of the power of the calculus as a language for lattice surgery by considering two operations (T gates and producing a CNOT ) and show how ZX diagram re-write rules give lattice surgery procedures for these operations that are novel, efficient, and highly configurable.
description: 20 pages, many figures. Minor revisions. Accepted to Quantum Journal
Photonic implementation of Majorana-based Berry phases
Creators: name: Xu, Jin-Shi
name: Sun, Kai
name: Pachos, Jiannis K.
name: Han, Yong-Jian
name: Li, Chuan-Feng
name: Guo, Guang-Can
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Geometric phases, generated by cyclic evolutions of quantum systems, offer an inspiring playground for advancing fundamental physics and technologies, alike. Intriguingly, the exotic statistics of anyons realised in physical systems can be interpreted as a topological version of geometric phases. However, non-Abelian statistics has not yet been demonstrated in the laboratory. Here we employ an all optical quantum system that simulates the statistical evolution of Majorana fermions. As a result we experimentally realise non-Abelian Berry phases with the topological characteristic that they are invariant under continues deformations of their control parameters. We implement a universal set of Majorana inspired gates by performing topological and non-topological evolutions and investigate their resilience against perturbative errors. Our photonic experiment, while it is not scalable, it suggests the intriguing possibility of experimentally simulating Majorana statistics with scalable technologies.
description: 8 pages, 4 figures
The analytic structure and the transcendental weight of the BFKL ladder at NLL accuracy
Creators: name: Del Duca, Vittorio
name: Duhr, Claude
name: Marzucca, Robin
name: Verbeek, Bram
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study some analytic properties of the BFKL ladder at next-to-leading logarithmic accuracy (NLLA). We use a procedure by Chirilli and Kovchegov to construct the NLO eigenfunctions, and we show that the BFKL ladder can be evaluated order by order in the coupling in terms of certain generalised single-valued multiple polylogarithms recently introduced by Schnetz. We develop techniques to evaluate the BFKL ladder at any loop order, and we present explicit results up to five loops. Using the freedom in defining the matter content of the NLO BFKL eigenvalue, we obtain conditions for the BFKL ladder in momentum space at NLLA to have maximal transcendental weight. We observe that, unlike in moment space, the result in momentum space in N = 4 SYM is not identical to the maximal weight part of QCD, and moreover that there is no gauge theory with this property. We classify the theories for which the BFKL ladder at NLLA has maximal weight in terms of their field content, and we find that these theories are highly constrained: there are precisely four classes of theories with this property involving only fundamental and adjoint matter, all of which have a vanishing one-loop beta function and a matter content that fits into supersymmetric multiplets. Our findings indicate that theories which have maximal weight are highly constrained and point to the possibility that there is a connection between maximal transcendental weight and superconformal symmetry.
description: 45 pages, 1 figure, 1 table. v2: published version
Electronic zero-point fluctuation forces inside circuit components
Creators: name: Shahmoon, Ephraim
name: Leonhardt, Ulf
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: One of the most intriguing manifestations of quantum zero-point fluctuations are the van der Waals and Casimir forces, often associated with vacuum fluctuations of the electromagnetic field. Here we study generalized fluctuation potentials acting on internal degrees of freedom of components in electrical circuits. These electronic Casimir-like potentials are induced by the zero-point current fluctuations of any general conductive circuit. For realistic examples of an electromechanical capacitor and a superconducting qubit, our results reveal the possibility of tunable forces between the capacitor plates, or the level shifts of the qubit, respectively. Our analysis suggests an alternative route towards the exploration of Casimir-like fluctuation potentials, namely, by characterizing and measuring them as a function of parameters of the environment. Such tunable potentials may be useful for future nanoelectromechanical and quantum technologies.
description: Published version has open access
Games with finitely generated structures
Creators: name: Krawczyk, Adam
name: Kubiś, Wiesław
Publisher: name: arXiv
Year: 2017
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03C07, 03C50

description: We study the abstract Banach-Mazur game played with finitely generated structures instead of open sets. We characterize the existence of winning strategies aiming at a single countably generated structure. We also introduce the concept of weak Fraisse classes, extending the classical Fraisse theory and revealing its relations to our Banach-Mazur game.
description: Last section extended (16 pages)
Cosmological reconstructed solutions in extended teleparallel gravity theories with a teleparallel Gauss-Bonnet term
Creators: name: de la Cruz-Dombriz, Alvaro
name: Farrugia, Gabriel
name: Said, Jackson Levi
name: Gomez, Diego Saez-Chillon
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In the context of extended Teleparallel gravity theories with a 3+1 dimensions Gauss-Bonnet analog term, we address the possibility of these theories reproducing several well-known cosmological solutions. In particular when applied to a Friedmann-Lemaître-Robertson-Walker geometry in four-dimensional spacetime with standard fluids exclusively. We study different types of gravitational Lagrangians and reconstruct solutions provided by analytical expressions for either the cosmological scale factor or the Hubble parameter. We also show that it is possible to find Lagrangians of this type without a cosmological constant such that the behaviour of the LCDM model is precisely mimicked. The new Lagrangians may also lead to other phenomenological consequences opening up the possibility for new theories to compete directly with other extensions of General Relativity.
description: 40 pages, 3 tables, 2 appendices. For a quick view: see Tables 1,2,3. Extended analysis and conclusions. Version published in CQG