cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Induced topological gravity and anomaly inflow from Kaehler-Dirac fermions in odd dimensions
Creators: name: Catterall, Simon
name: Pradhan, Arnab
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We show that the effective action that results from integrating out massive Kaehler-Dirac fermions propagating on a curved three dimensional space is a topological gravity theory of Chern-Simons type. In the presence of a domain wall, massless, two dimensional Kaehler-Dirac fermions appear that are localized to the wall. Potential gravitational anomalies arising for these domain wall fermions are cancelled via anomaly inflow from the bulk gravitational theory. We also study the invariance of the theory under large gauge transformations. The analysis and conclusions generalize straightforwardly to higher dimensions.
description: 9 pages. 3 figures. Version to be published in PRD
Virtual staining of defocused autofluorescence images of unlabeled tissue using deep neural networks
Creators: name: Zhang, Yijie
name: Huang, Luzhe
name: Liu, Tairan
name: Cheng, Keyi
name: de Haan, Kevin
name: Li, Yuzhu
name: Bai, Bijie
name: Ozcan, Aydogan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Deep learning-based virtual staining was developed to introduce image contrast to label-free tissue sections, digitally matching the histological staining, which is time-consuming, labor-intensive, and destructive to tissue. Standard virtual staining requires high autofocusing precision during the whole slide imaging of label-free tissue, which consumes a significant portion of the total imaging time and can lead to tissue photodamage. Here, we introduce a fast virtual staining framework that can stain defocused autofluorescence images of unlabeled tissue, achieving equivalent performance to virtual staining of in-focus label-free images, also saving significant imaging time by lowering the microscope's autofocusing precision. This framework incorporates a virtual-autofocusing neural network to digitally refocus the defocused images and then transforms the refocused images into virtually stained images using a successive network. These cascaded networks form a collaborative inference scheme: the virtual staining model regularizes the virtual-autofocusing network through a style loss during the training. To demonstrate the efficacy of this framework, we trained and blindly tested these networks using human lung tissue. Using 4x fewer focus points with 2x lower focusing precision, we successfully transformed the coarsely-focused autofluorescence images into high-quality virtually stained H&E images, matching the standard virtual staining framework that used finely-focused autofluorescence input images. Without sacrificing the staining quality, this framework decreases the total image acquisition time needed for virtual staining of a label-free whole-slide image (WSI) by ~32%, together with a ~89% decrease in the autofocusing time, and has the potential to eliminate the laborious and costly histochemical staining process in pathology.
description: 26 Pages, 5 Figures
What is a good medical decision? A research agenda guided by perspectives from multiple stakeholders
Creators: name: Goldstein, Mary K.
name: Brewster, Mikki
name: Craddock Lee, Simon
name: Rini, Christine
name: Waters, Erika A.
name: Oser, Megan
name: Baleix, John
name: Zikmund-Fisher, Brian J.
name: Tanaka, Miho
name: Lillie, Sarah E.
name: Jacobson, Robert M.
name: Myers, Ronald E.
name: Scherer, Laura
name: Alden, Dana L.
name: Hamilton, Jada G.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2017

description: Informed and shared decision making are critical aspects of patient-centered care, which has contributed to an emphasis on decision support interventions to promote good medical decision making. However, researchers and healthcare providers have not reached a consensus on what defines a good decision, nor how to evaluate it. This position paper, informed by conference sessions featuring diverse stakeholders held at the 2015 Society of Behavioral Medicine and Society for Medical Decision Making annual meetings, describes key concepts that influence the decision making process itself and that may change what it means to make a good decision: interpersonal factors, structural constraints, affective influences, and values clarification methods. This paper also proposes specific research questions within each of these priority areas, with the goal of moving medical decision making research to a more comprehensive definition of a good medical decision, and enhancing the ability to measure and improve the decision making process.
Matrix Product States with Backflow correlations
Creators: name: Lami, Guglielmo
name: Carleo, Giuseppe
name: Collura, Mario
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: By taking inspiration from the backflow transformation for correlated systems, we introduce a novel tensor network ansatz which extend the well-established Matrix Product State representation of a quantum-many body wave function. This new structure provides enough resources to ensure that states in dimension larger or equal than one obey an area law for entanglement. It can be efficiently manipulated to address the ground-state search problem by means of an optimization scheme which mixes tensor-network and variational Monte-Carlo algorithms. We benchmark the new ansatz against spin models both in one and two dimensions, demonstrating high accuracy and precision. We finally employ our approach to study the challenging $S=1/2$ two dimensional $J_1 - J_2$ model, demonstrating that it is competitive with the state of the art methods in 2D.
Osaka Feedback Model II: Modeling Supernova Feedback Based on High-Resolution Simulations
Creators: name: Oku, Yuri
name: Tomida, Kengo
name: Nagamine, Kentaro
name: Shimizu, Ikkoh
name: Cen, Renyue
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Feedback from supernovae (SNe) is an essential mechanism that self-regulates the growth of galaxies, and a better model of SN feedback is still needed in galaxy formation simulations. In the first part of this paper, using an Eulerian hydrodynamic code Athena++, we find universal scaling relations for the time evolution of momentum and radius for a superbubble, when the momentum and time are scaled by those at the shell-formation time. In the second part of this paper, we develop an SN feedback model based on the Athena++ simulation results utilizing Voronoi tessellation around each star particle, and implement it into the GADGET3-Osaka smoothed particle hydrodynamic code. Our feedback model was demonstrated to be isotropic and conservative in terms of energy and momentum. We examined the mass/energy/metal loading factors and find that our stochastic thermal feedback model produced galactic outflow that carries metals high above the galactic plane but with weak suppression of star formation. Additional mechanical feedback further suppressed star formation and brought the simulation results in better agreement with the observations of the Kennicutt--Schmidt relation, with all the results being within the uncertainties of observed data. We argue that both thermal and mechanical feedback are necessary for the SN feedback model of galaxy evolution when an individual SN bubble is unresolved.
description: 36 pages, 22 figures, accepted for publication in The Astrophysical Journal Supplement Series. Movies available at https://www.yurioku.com/research/
A corrugated planar-Goubau-line termination for terahertz waves
Creators: name: Cabello-Sánchez, Juan
name: Drakinskiy, Vladimir
name: Stake, Jan
name: Rodilla, Helena
Publisher: name: arXiv
Year: 2022
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: The planar Goubau line is a promising low-loss metal waveguide for terahertz interconnects. To enable advanced system architectures and multi-port measurements based on planar Goubau lines, there is a strong need for broadband impedance-matched loads, which can be used to absorb the energy and minimize standing waves in a system. In this work, we propose a matched load for planar Goubau lines based on an exponentially-tapered corrugated line, gradually increasing conductor losses while maintaining small reflections. The corrugation density is high enough to increase conductor losses without requiring an auxiliary low-conductivity material, simplifying the fabrication process. A 400-$μ$m long planar Goubau line load was fabricated on a 10-$μ$m thick silicon substrate suspended in the air. Electromagnetic simulations of the load show excellent agreement with calibrated reflection measurements in the frequency range 0.5 THz - 1.1 THz. Above the cut-off frequency of around 580 GHz, the measured reflections are much less than -19 dB, below the noise floor of the characterization setup.
Harnessing Administrative Data Inventories to Create a Reliable Transnational Reference Database for Crop Type Monitoring
Creators: name: Schneider, Maja
name: Körner, Marco
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: With leaps in machine learning techniques and their applicationon Earth observation challenges has unlocked unprecedented performance across the domain. While the further development of these methods was previously limited by the availability and volume of sensor data and computing resources, the lack of adequate reference data is now constituting new bottlenecks. Since creating such ground-truth information is an expensive and error-prone task, new ways must be devised to source reliable, high-quality reference data on large scales. As an example, we showcase E URO C ROPS, a reference dataset for crop type classification that aggregates and harmonizes administrative data surveyed in different countries with the goal of transnational interoperability.
title: Die Änderungen der WEG-Novelle 2022 im Hinblick auf den Klimaschutz
Creators: name: Fock, Freia Fee
Year: 2023

description: Die Bewältigung der Klimakrise als eine der größten Herausforderungen unserer Zeit er- fordert ein Bündel unterschiedlichster und ambitionierter Maßnahmen. Die WEG-Novelle kann dabei nur einen Teilbereich beeinflussen und vor allem einen Beitrag zur nach- haltigen Transformation im Gebäude- und Verkehrssektor leisten. Diese Arbeit soll einen Überblick über die globalen und nationalen klimapolitischen Bestrebungen geben, um die Neuerungen der WEG-Novelle 2022 einordnen zu können. In weiterer Folge werden die Änderungen im Detail diskutiert und analysiert. Abschließend werden die Ergebnisse zusammengefasst und Verbesserungsmöglichkeiten aufgezeigt. Es stellt sich vor allem die Frage, ob im Bereich des Wohnungseigentumsrechts ein geeigneter Grundstein gelegt wurde.
Transmutation operators and expansions for $1$-loop Feynman integrands
Creators: name: Zhou, Kang
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper, the connections among $1$-loop Feynman integrands of a large variety of theories with massless external states are further investigated. The work includes two parts. First, we construct a new class of differential operators which transmute the $1$-loop gravitational Feynman integrands to $1$-loop Yang-Mills Feynman integrands. The new operators are commutable with the integration of loop momentum, thus the corresponding transmutational relations hold at not only the integrands level, but also the $1$-loop amplitudes level. Secondly, by using $1$-loop level transmutational relations, together with some general requirements such as gauge and Lorentz invariance, we derive the expansions of the Feynman integrands of one theory to those of other theories. The unified web for expansions is established, including a wide range of theories which are gravitational theory, Einstein-Yang-Mills theory, Einstein-Maxwell theory, Born-Infeld theory, pure Yang-Mills theory, Yang-Mills-scalar theory, special Yang-Mills-scalar theory, Dirac-Born-Infeld theory, extended Dirac-Born-Infeld theory, special Galileon theory, non-linear sigma model. The systematic rules for evaluating coefficients in the expansions are provided, and the duality between transmutational relations and expansions is shown.
description: 53 pages, 4 figures, 6 tables
On the sub-parsec scale core composition of FR 0 radio galaxies
Creators: name: Boughelilba, Margot
name: Reimer, Anita
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Although Fanaroff-Riley (FR) type 0 radio galaxies are known to be the most numerous jet population in the local Universe, they are much less explored than the well-established class of FR I and FR II galaxies due to their intrinsic weakness. Observationally, their nuclear radio, optical and X-ray properties are comparable to the nuclear environment of FR Is. The recent detection of two FR 0s in the high-energy band suggests that like in FR Is, charged particles are accelerated there to energies that enable gamma-ray production. Up to now, only the lack of extended radio emission from FR 0s distinguishes them from FR Is. By comparing the spectral energy distribution of FR 0s with that of FR Is and in particular with that of M87 as a well-studied reference source of the FR I population, we find the broadband spectrum of FR 0s exceptionally close to M87's quiet core emission. Relying on that similarity, we apply a lepto-hadronic jet-accretion flow model to FR 0s. This model is able to explain the broadband spectral energy distribution, with parameters close to particle-field equipartition and matching all observational constraints. In this framework, FR 0s are multi-messenger jet sources, with a nature and highly magnetized environment similar to that of the naked quiet core of FR Is.
description: Published in ApJL on 2023 October 4, data is available at https://iopscience.iop.org/article/10.3847/2041-8213/acf83c
Field Theory of Interacting Boundary Gravitons
Creators: name: Ebert, Stephen
name: Hijano, Eliot
name: Kraus, Per
name: Monten, Ruben
name: Myers, Richard M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Pure three-dimensional gravity is a renormalizable theory with two free parameters labelled by $G$ and $Λ$. As a consequence, correlation functions of the boundary stress tensor in AdS$_3$ are uniquely fixed in terms of one dimensionless parameter, which is the central charge of the Virasoro algebra. The same argument implies that AdS$_3$ gravity at a finite radial cutoff is a renormalizable theory, but now with one additional parameter corresponding to the cutoff location. This theory is conjecturally dual to a $T\overline{T}$-deformed CFT, assuming that such theories actually exist. To elucidate this, we study the quantum theory of boundary gravitons living on a cutoff planar boundary and the associated correlation functions of the boundary stress tensor. We compute stress tensor correlation functions to two-loop order ($G$ being the loop counting parameter), extending existing tree level results. This is made feasible by the fact that the boundary graviton action simplifies greatly upon making a judicious field redefinition, turning into the Nambu-Goto action. After imposing Lorentz invariance, the correlators at this order are found to be unambiguous up to a single undetermined renormalization parameter.
description: 71 pages, 1 figure, typos corrected and clarifications added in response to the referees' questions
Planar Black Holes as a Route to Understanding the Weak Gravity Conjecture
Creators: name: McInnes, Brett
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: One version of the Weak Gravity Conjecture requires that it should be possible for an extremal black hole to emit a smaller black hole: that is, the original black hole bifurcates. For asymptotically flat and asymptotically AdS Reissner-Nordström black holes with spherical event horizons, such a bifurcation reduces the total classical entropy of the system, and so it is apparently forbidden by the second law of thermodynamics. It may well be possible to remedy this by taking other (for example, quantum-gravitational) effects into account, but it is difficult to understand this in a quantitative way. In the case of asymptotically AdS Reissner-Nordström black holes with \emph{planar} event horizons, however, one can show that bifurcations are definitely compatible with the second law. (Naked singularities, generated by the bifurcation, may play an important role here.) Furthermore, in this case one can exhibit a detailed mechanism explaining precisely why planar black holes must indeed be unstable (through emission of branes) when they are sufficiently close to extremality. Thus planar black holes can improve our understanding of the WGC.
description: Non-dependence of results on energy conditions stressed; 18 pages, no figures; version appearing in NPB
Ghost instability in the teleparallel gravity model with parity violations
Creators: name: Li, Mingzhe
name: Li, Zhihao
name: Rao, Haomin
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this paper we consider the parity violating gravity model within the framework of teleparallel gravity. The parity violations are caused by the couplings of a scalar field to the scalar invariants which are parity-odd and quadratic in the torsion tensor. Totally there are two such type independent invariants, and one of them is the Nieh-Yan density. Through investigations on the cosmological perturbations of this model, we find that in general it suffers from the difficulties of ghost instability in the scalar and vector perturbations. But in the special case only the coupling to the Nieh-Yan density exists, this model is ghost free and reduces to the Nieh-Yan modified Teleparallel Gravity model. We also analyze the severity of the ghost instability by studying the perturbations around the Minkowski background.
description: 11 pages, 0 figure, teleparallel gravity, parity violation
Veneziano Variations: How Unique are String Amplitudes?
Creators: name: Cheung, Clifford
name: Remmen, Grant N.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: String theory offers an elegant and concrete realization of how to consistently couple states of arbitrarily high spin. But how unique is this construction? In this paper we derive a novel, multi-parameter family of four-point scattering amplitudes exhibiting i) polynomially bounded high-energy behavior and ii) exchange of an infinite tower of high-spin modes, albeit with a finite number of states at each resonance. These amplitudes take an infinite-product form and, depending on parameters, exhibit mass spectra that are either unbounded or bounded, thus corresponding to generalizations of the Veneziano and Coon amplitudes, respectively. For the bounded case, masses converge to an accumulation point, a peculiar feature seen in the Coon amplitude but more recently understood to arise naturally in string theory. Importantly, our amplitudes contain free parameters allowing for the customization of the slope and offset of the spin-dependence in the Regge trajectory. We compute all partial waves for this multi-parameter class of amplitudes and identify unitary regions of parameter space. For the unbounded case, we apply similar methods to derive new deformations of the Veneziano and Virasoro-Shapiro amplitudes.
description: 32 pages, 3 figures
title: Maschinelle Übersetzung: Rolle und Stellenwert in der Flüchtlingswelle 2022 in Österreich
Creators: name: Semenyuk, Maryna
Year: 2023

description: Die vorliegende Masterarbeit fokussiert sich auf die Analyse der Anwendung maschineller Übersetzung (MÜ) durch ukrainische Flüchtlinge in Österreich infolge der russischen Invasion vom 24. Februar 2022. Angesichts der vorhandenen Sprachbarrieren zwischen den Flüchtlingen und ihrem Zielland Österreich erlangt die Relevanz moderner Sprachtechnologien und Übersetzungssysteme für die Flüchtlingskommunikation erhebliche Bedeutung. Ziel dieser Arbeit ist es, den Umfang und die Art der Nutzung von MÜ durch ukrainische Flüchtlinge in Österreich zur Bewältigung ihrer Kommunikationsanforderungen zu erforschen. Im theoretischen Teil werden die historische Entwicklung, unterschiedliche Kategorien maschineller Übersetzung und relevante MÜ-Tools ausführlich behandelt. Ebenso erfolgt eine Analyse der Anwendung von MÜ sowohl durch professionelle Übersetzer:innen als auch durch Lai:innen. Die Hauptzielsetzung dieser Untersuchung liegt in der Analyse der MÜ-Anwendung bei ukrainischen Flüchtlingen und deren Einfluss auf die Kommunikation und das Verständnis in verschiedenen Kontexten. Die erzielten Resultate bieten tiefe Einblicke in die Erfahrungen und Sichtweisen der Flüchtlinge bezüglich der MÜ-Nutzung, einschließlich der damit verbundenen Erleichterungen und Herausforderungen. Nach der Umsiedlung stieg die Nutzung von MÜ, insbesondere des Google Übersetzers, signifikant an. Es zeigt sich, dass 100% der Proband:innen den Google Übersetzer zur Überwindung von Sprachbarrieren einsetzen. Die identifizierten Herausforderungen, wie beispielsweise Übersetzungsqualität, Geschwindigkeit des Prozesses, Frustration und Missverständnisse, wurden von den Befragten einheitlich benannt. Es sei betont, dass die Analyse der MÜ-Nutzung im Flüchtlingskontext nicht nur für die Übersetzungswissenschaft von Relevanz ist, sondern auch politische Implikationen aufzeigt. Durch die Untersuchung von Kommunikationslücken bei ukrainischen Flüchtlingen und die Analyse der am häufigsten verwendeten Übersetzungssysteme kann der effektive Einsatz von MÜ in künftigen Flüchtlingsströmen optimiert werden. Diese Untersuchung zur MÜ-Nutzung während der ukrainischen Migrationskrise trägt nicht nur zur Bewältigung aktueller Flüchtlingsströme bei, sondern ist auch für die Übersetzungswissenschaft und die fortlaufende Entwicklung maschineller Übersetzungssysteme von Bedeutung.
Nevanlinna theory via holomorphic forms
Creators: name: Dong, Xianjing
name: Yang, Shuangshuang
Publisher: name: arXiv
Year: 2022
Subjects: subject: Complex Variables (math.CV)
subject: FOS: Mathematics
subject: 30D35

description: This paper re-develops the Nevanlinna theory for meromorphic functions on $\mathbb C$ in the viewpoint of holomorphic forms. According to our observation, Nevanlinna's functions can be formulated by a holomorphic form. Applying this thought to Riemann surfaces, one then extends the definition of Nevanlinna's functions using a holomorphic form $\mathscr S$. With the new settings, an analogue of Nevanlinna theory on \emph{weak $\mathscr S$-exhausted Riemann surfaces} is obtained, which is viewed as a generalization of the classical Nevanlinna theory on $\mathbb C$ and $\mathbb D.$
description: This is a final version, prepared for publication in Pacific Journal of Mathematics
MPEC 2023-Q118 : 2023 QQ4
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2023
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2023 QQ4

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Nuclear and magnetic spin structure of the antiferromagnetic triangular lattice compound LiCrTe$_2$ investigated by $μ^+$SR as well as neutron and X-ray diffraction
Creators: name: Nocerino, E.
name: Witteveen, C.
name: Kobayashi, S.
name: Forslund, O. K.
name: Matsubara, N.
name: Zubayer, A.
name: Mazza, F.
name: Kawaguchi, S.
name: Hoshikawa, A.
name: Umegaki, I.
name: Sugiyama, J.
name: Yoshimura, K.
name: Sassa, Y.
name: von Rohr, F. O.
name: Månsson, M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Two$-$dimensional (2D) triangular lattices antiferromagnets (2D$-$TLA) often manifest intriguing physical and technological properties, due to the strong interplay between lattice geometry and electronic properties. The recently synthesized 2$-$dimensional transition metal dichalcogenide LiCrTe$_2$, being a 2D$-$TLA, enriched the range of materials which can present such properties. In this work, muon spin rotation ($μ^+$SR) and neutron powder diffraction (NPD) have been utilized to reveal the true magnetic nature and ground state of LiCrTe$_2$. From high$-$resolution NPD the magnetic spin order at base$-$temperature is not, as previously suggested, helical, but rather collinear antiferromagnetic (AFM) with ferromagnetic (FM) spin coupling within the $ab-$plane and AFM coupling along the $c-$axis. The ordered magnetic Cr moment is established as $μ_{\rm Cr}=$ 2.36 $μ_{\rm B}$. From detailed $μ^+$SR measurements we observe an AFM ordering temperature $T_{\rm N}\approx$ 125 K. This value is remarkably higher than the one previously reported by magnetic bulk measurements. From $μ^+$SR we are able to extract the magnetic order parameter, whose critical exponent allows us to categorize LiCrTe$_2$ in the 3D Heisenberg AFM universality class. Finally, by combining our magnetic studies with high$-$resolution synchrotron X$-$ray diffraction (XRD), we find a clear coupling between the nuclear and magnetic spin lattices. This suggests the possibility for a strong magnon$-$phonon coupling, similar to what has been previously observed in the closely related compound LiCrO$_2$.
Intrinsic Nonlinear Spin Magnetoelectricity in Centrosymmetric Magnets
Creators: name: Xiao, Cong
name: Liu, Huiying
name: Wu, Weikang
name: Wang, Hui
name: Niu, Qian
name: Yang, Shengyuan A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We propose an intrinsic nonlinear spin magnetoelectric effect in magnetic materials, offering the potential of all-electric control of spin degree of freedom in centrosymmetric magnets, which reside outside of the current paradigm based on linear spin response. We reveal the band geometric origin of this effect in the momentum and magnetization space Berry connection polarizabilities, and clarify its symmetry characters. As an intrinsic effect, it is determined solely by the material's band structure and represents a material characteristic. Combining our theory with first-principles calculations, we predict sizable nonlinear spin magnetoelectricity in single-layer MnBi$_{2}$Te$_{4}$, which can be detected in experiment. Our theory paves the way for exploring rich nonlinear spintronic effects and novel device concepts based on them.
Q-balls in polynomial potentials
Creators: name: Heeck, Julian
name: Sokhashvili, Mikheil
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Bosons carrying a conserved charge can form stable bound states if their Lagrangian contains attractive self-interactions. Bound-state configurations with a large charge $Q$ can be described classically and are denoted as Q-balls, their properties encoded in a non-linear differential equation. Here, we study Q-balls in arbitrary polynomial single-scalar-field potentials both numerically and via various analytical approximations. We highlight some surprising universal features of Q-balls that barely depend on the details of the potential. The polynomial potentials studied here can be realized in renormalizable models involving additional heavy or light scalars, as we illustrate with several examples.
description: 13 pages, matches PRD version
Effectiveness of the Self-Consistent Harmonic Approximation in ferromagnets with dipolar interactions
Creators: name: Moura, A. R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Among the various methods for treating magnetic models, the Self-Consistent Harmonic Approximation (SCHA) has successfully described ferro and antiferromagnetism in many different scenarios. In particular, the SCHA is a valuable and easy formalism for determining transition temperatures as, for example, the Berezinskii-Kosterlitz-Thouless. The heart of the method includes thermal fluctuations through of a renormalization parameter depending on temperature. Nevertheless, most of the work has been done considering only short-range interactions, which results in an incomplete description of actual magnetic samples. Here, we generalize the SCHA to include the dipolar interaction in the thermodynamic analysis. The method is applied to analyze the well-known Europium Chalcogenides EuO and EuS. The SCHA results are in good agreement with the experimental measurements.
description: 10 pages, 6 figures
Experimental Evidence of Large Collective Enhancement of Nuclear Level Density and its Significance in Radiative Neutron Capture
Creators: name: Santhosh, T.
name: Rout, P. C.
name: Santra, S.
name: Shrivastava, A.
name: Mohanto, G.
name: Pandit, S. K.
name: Pal, A.
name: Gandhi, Ramandeep
name: Baishya, A.
name: Dhuri, Sangeeta
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The collective enhancement of nuclear level density and its fade out with excitation energy in deformed $^{171}$Yb nucleus has been inferred through an exclusive measurement of neutron spectra.The statistical model analysis of neutron spectra demonstrated a large collective enhancement factor of 40$\pm$3 for the first time, which corroborates with the recent microscopic model predictions but is an anomalous result compared with the measurements in the nearby deformed nuclei. The complete picture of the energy dependent collective enhancement has been obtained by combining with Oslo data below neutron binding energy. The significance of large collective enhancement in radiative neutron capture cross section of astrophysical interest is highlighted.
description: 12 pages, 5 figures
$Z_2$ Dirac points with topologically protected multihelicoid surface states
Creators: name: Zhang, Tiantian
name: Hara, Daisuke
name: Murakami, Shuichi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In some Dirac systems with time-reversal (T) and glide (G) symmetries, multihelicoid surface states (MHSSs) appear, as discussed in various systems such as electronic and photonic ones. However, the topological nature and the conditions for the appearance of the MHSSs have not been understood. Here we show that MHSSs result from bulk-surface correspondence for the $Z_2$ monopole charge Q, which cannot be defined as a local quantity associated with the Dirac point, unlike the Z monopole charge characterizing Weyl points. The previously known formula of Q turns out to be non-gauge-invariant and thus cannot characterize the MHSSs. This shortcoming of the definition of Q is amended by redefining Q as a global topological invariant in k-space. Surprisingly, the newly defined Q, characterizing GT invariant gapless systems, is equal to the G-protected $Z_2$ topological invariant v, which is nontrivial only in T-breaking gapped systems. This global definition of Q automatically guarantees the appearance of MHSSs even when the Dirac point splits into Weyl points or a nodal ring by lowering the symmetry, as long as the GT symmetry is preserved. Q can be simplified to symmetry-based indicators when two vertical Gs are preserved, and filling-enforced topological crystalline insulators are diagnosed in several cases when a T-breaking perturbation is induced. Material candidate Li2B4O7 together with a list of space groups preserving MHSSs are also proposed.
description: 10 pages, 5 figures, 1 table
Data-driven approach in a compartmental epidemic model to assess undocumented infections
Creators: name: Costa, Guilherme S.
name: Cota, Wesley
name: Ferreira, Silvio C.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: Nowcasting and forecasting of epidemic spreading rely on incidence series of reported cases to derive the fundamental epidemiological parameters for a given pathogen. Two relevant drawbacks for predictions are the unknown fractions of undocumented cases and levels of nonpharmacological interventions, which span highly heterogeneously across different places and times. We describe a simple data-driven approach using a compartmental model including asymptomatic and presymptomatic contagions that allows to estimate both the level of undocumented infections and the value of effective reproductive number R t from time series of reported cases, deaths, and epidemiological parameters. The method was applied to epidemic series for COVID-19 across different municipalities in Brazil allowing to estimate the heterogeneity level of under-reporting across different places. The reproductive number derived within the current framework is little sensitive to both diagnosis and infection rates during the asymptomatic states. The methods described here can be extended to more general cases if data is available and adapted to other epidemiological approaches and surveillance data.
description: Revised version; 10 pages, 7 figures. Supplementary figures available as ancillary files
A Parameter-Free Differential Evolution Algorithm for the Analytic Continuation of Imaginary Time Correlation Functions
Creators: name: Nichols, Nathan S.
name: Sokol, Paul
name: Del Maestro, Adrian
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We report on Differential Evolution for Analytic Continuation (DEAC): a parameter-free evolutionary algorithm to generate the dynamic structure factor from imaginary time correlation functions. Our approach to this long-standing problem in quantum many-body physics achieves enhanced spectral fidelity while using fewer compute (CPU) hours. The need for fine-tuning of algorithmic control parameters is eliminated by embedding them within the genome to be optimized for this evolutionary computation based algorithm. Benchmarks are presented for models where the dynamic structure factor is known exactly, and experimentally relevant results are included for quantum Monte Carlo simulations of bulk $^4$He below the superfluid transition temperature.
description: 10 pages, 6 figures. For associated data and code repository see: https://github.com/DelMaestroGroup/papers-code-DEAC
ลักษณะการกัดเซาะชายฝั่งหน้าผา และแนวทางการจัดการ: กรณีศึกษา บ้านฝั่งแดงจังหวัดประจวบคีรีขันธ์
Creators: name: ศุภกร เทกมล
Publisher: name: คณะบริหารการพัฒนาสิ่งแวดล้อม สถาบันบัณฑิตพัฒนบริหารศาสตร์
Year: 2022
Subjects: การกัดเซาะชายฝั่งหน้าผา
การจัดการชายฝั่ง
การเปลี่ยนแปลงชายฝั่ง

description: วารสารการจัดการสิ่งแวดล้อม, 18, 2, 26-43
Quantum Dynamics of Cold Atomic Gas with $SU(1,1)$ Symmetry
Creators: name: Zhang, Jing
name: Yang, Xiaoyi
name: Lv, Chenwei
name: Ma, Shengli
name: Zhang, Ren
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Motivated by recent advances in quantum dynamics, we investigate the dynamics of the system with $SU(1,1)$ symmetry. Instead of performing the time-ordered integral for the evolution operator of the time-dependent Hamiltonian, we show that the time evolution operator can be expressed as an $SU(1,1)$ group element. Since the $SU(1,1)$ group describes the "rotation" on a hyperbolic surface, the dynamics can be visualized on a Poincaré disk, a stereographic projection of the upper hyperboloid. As an example, we present the trajectory of the revival of Bose-Einstein condensation and that of the scale-invariant Fermi gas on the Poincaré disk. Further considering the quantum gas in the oscillating lattice, we also study the dynamics of the system with time-dependent single-particle dispersion. Our results are hopefully to be checked in current experiments.
description: 10 pages,4,figures
title: Die Wirkung von außerschulischen Lernorten auf die Umweltkompetenz von Schüler*innen im Kontext der Bildung für nachhaltige Entwicklung
Creators: name: Prinz, Sarah
Year: 2023

description: Hochwertige Bildung, die eine Vermittlung von Werten und Wissen rund um Nachhaltigkeit bietet, ist eine Voraussetzung der von der UN präsentierten SDG’s. Schulen tragen eine hohe Verantwortung bei der Umsetzung dieses Ziels durch das übergeordnete Unterrichtsprinzip der Bildung für nachhaltige Entwicklung. Umweltkompetenzen, also Umweltwissen, Umweltbewusstsein und Umweltverhalten ist diesem Konzept entsprechend im Unterricht miteinzubeziehen und zu fördern. Dazu werden in dieser Arbeit grundlegende Theorien, wie die PBT, SIT und die Low-Cost-Hypothese vorgestellt und in praktischen Zusammenhang mit Modellen und Prinzipien zur Umweltbildung, wie dem Rahmenmodell zur BNE und der Environmental Literacy gebracht. Das in der Theorie eingebettete Modell zur Messung der Umweltkompetenz wird anhand einer Kooperation zwischen einem außerschulischen Lernort, einer Müllbehandlungsanlage und dreier Klassen der Sekundarstufe II auf Umsetzbarkeit geprüft. Es zeigt sich, dass vor allem in Bezug auf das Umweltwissen Änderungen erzielt werden. Das Umweltbewusstsein und Umweltverhalten basiert auf einem komplexen System, das von sozialen Einflüssen, Motivation und Interesse der Schüler*innen abhängig ist. Es konnte im Rahmen dieser Querschnittsstudie, die an zwei Erhebungszeitpunkten, einem Pretest vor der Intervention und einem Posttest nach der Intervention, keine weiteren eindeutigen Veränderungen festgestellt werden.
description: High-quality education that promotes values and increases knowledge about sustainability is a prerequisite for the Sustainable Development Goals (SDGs) presented by the UN. Schools bear a high responsibility in implementing this goal through the overarching educational principle of Education for Sustainable Development. Accordingly, environmental competences, including environmental knowledge, environmental awareness, and environmental behavior, should be integrated and promoted in the curriculum. This work presents fundamental theories such as the PBT, SIT, and the Low-Cost Hypothesis, and relates them practically to models and principles of environmental education, such as the framework model for Education for Sustainable Development (BNE) and Environmental Literacy. The theoretically embedded model for measuring environmental competence is tested for feasibility through a collaboration between an extracurricular learning environment, a waste treatment facility, and three classes at upper secondary level. The results indicate that significant changes are primarily achieved regarding environmental knowledge. Environmental awareness and behavior are subject to a complex system influenced by social factors, motivation, and students' interest. No further significant changes could be observed within the scope of this cross-sectional study, which included two data collection points: a pretest before the intervention and a posttest after the intervention.
โครงการเกษตรอาหารกลางวันให้แก่โรงเรียนที่ขาดแคลนตามแนวทางปรัชญาของเศรษฐกิจพอเพียง
Creators: name: สุปรีณา ศรีใสคำ
Publisher: name: คณะบริหารการพัฒนาสิ่งแวดล้อม สถาบันบัณฑิตพัฒนบริหารศาสตร์
Year: 2022
Subjects: โครงการเกษตร
อาหารกลางวัน
โรงเรียนที่ขาดแคลน
แนวทางปรัชญาของเศรษฐกิจพอเพียง

description: วารสารการจัดการสิ่งแวดล้อม, 18, 2, 44-57
Designing robots with the context in mind -- One design does not fit all
Creators: name: Liberman-Pincu, Ela
name: van Grondelle, Elmer D.
name: Oron-Gilad, Tal
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Robots' visual qualities (VQs) impact people's perception of their characteristics and affect users' behaviors and attitudes toward the robot. Recent years point toward a growing need for Socially Assistive Robots (SARs) in various contexts and functions, interacting with various users. Since SAR types have functional differences, the user experience must vary by the context of use, functionality, user characteristics, and environmental conditions. Still, SAR manufacturers often design and deploy the same robotic embodiment for diverse contexts. We argue that the visual design of SARs requires a more scientific approach considering their multiple evolving roles in future society. In this work, we define four contextual layers: the domain in which the SAR exists, the physical environment, its intended users, and the robot's role. Via an online questionnaire, we collected potential users' expectations regarding the desired characteristics and visual qualities of four different SARs: a service robot for an assisted living/retirement residence facility, a medical assistant robot for a hospital environment, a COVID-19 officer robot, and a personal assistant robot for domestic use. Results indicated that users' expectations differ regarding the robot's desired characteristics and the anticipated visual qualities for each context and use case.
description: Accepted to the 15th International Workshop on Human-Friendly Robotics
Non-Gaussian Variational Wavefunctions for Interacting Bosons on the Lattice
Creators: name: Qian, Tian
name: Fernandez-Melgarejo, Jose J.
name: Zueco, David
name: Molina-Vilaplana, Javier
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A variational method for studying the ground state of strongly interacting quantum many-body bosonic systems is presented. Our approach constructs a class of extensive variational non-Gaussian wavefunctions which extend Gaussian states by means of nonlinear canonical transformations (NLCT) on the fields of the theory under consideration. We illustrate this method with the one dimensional Bose-Hubbard model for which the proposal presented here, provides a family of approximate ground states at arbitrarily large values of the interaction strength. We find that, for different values of the interaction, the non-Gaussian NLCT-trial states sensibly improve the ground state energy estimation when the system is in the Mott phase.
description: 10 pages, 2 figures
Stochastic representation of processes with resetting
Creators: name: Magdziarz, Marcin
name: Taźbierski, Kacper
Publisher: name: arXiv
Year: 2023
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: G.3
subject: 60J75

description: In this paper we introduce a general stochastic representation for an important class of processes with resetting. It allows to describe any stochastic process intermittently terminated and restarted from a predefined random or non-random point. Our approach is based on stochastic differential equations called jump-diffusion models. It allows to analyze processes with resetting both, analytically and using Monte Carlo simulation methods. To depict the strength of our approach, we derive a number of fundamental properties of Brownian motion with Poissonian resetting, such as: the Itô lemma, the moment-generating function, the characteristic function, the explicit form of the probability density function, moments of all orders, various forms of the Fokker-Planck equation, infinitesimal generator of the process and its adjoint operator. Additionally, we extend the above results to the case of time-nonhomogeneous Poissonian resetting. This way we build a general framework for the analysis of any stochastic process with intermittent random resetting.
Observables from spherically symmetric modified dispersion relations
Creators: name: Läänemets, Dagmar
name: Hohmann, Manuel
name: Pfeifer, Christian
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this work we continue the systematic study of observable effects emerging from modified dispersion relations. We study the motion of test particles subject to a general first order modification of the general relativistic dispersion relation as well as subject to the $κ$-Poincaré dispersion relation in spherical symmetry. We derive the corrections to the photon sphere, the black hole shadow, the Shapiro delay and the light deflection and identify the additional dependence of these observables on the photons' four momentum, which leads to measurable effects that can be compared to experimental data. The results presented here can be interpreted in two ways, depending on the origin of the modified dispersion relation: on the one hand as prediction for traces of quantum gravity, when the modified dispersion relation is induced by phenomenological approaches to quantum gravity, on the other hand as predictions of observables due to the presence of a medium, like a plasma, which modifies the dispersion relation of light on curved spacetimes.
description: Contribution to the Special Issue of the International Journal of Geometric Methods in Modern Physics dedicated to the conference Geometric Foundations of Gravity 2021, journal version