cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Single-photon single ionization of W$^{+}$ ions: experiment and theory
Creators: name: Müller, A.
name: Schippers, S.
name: Hellhund, J.
name: Holste, K.
name: Kilcoyne, A. L. D.
name: Phaneuf, R. A.
name: Ballance, C. P.
name: McLaughlin, B. M.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Experimental and theoretical results are reported for photoionization of Ta-like (W$^{+}$) tungsten ions. Absolute cross sections were measured in the energy range 16 to 245 eV employing the photon-ion merged-beam setup at the Advanced Light Source in Berkeley. Detailed photon-energy scans at 100 meV bandwidth were performed in the 16 to 108 eV range. In addition, the cross section was scanned at 50 meV resolution in regions where fine resonance structures could be observed. Theoretical results were obtained from a Dirac-Coulomb R-matrix approach. Photoionization cross section calculations were performed for singly ionized atomic tungsten ions in their $5s^2 5p^6 5d^4({^5}D)6s \; {^6}{\rm D}_{J}$, $J$=1/2, ground level and the associated excited metastable levels with $J$=3/2, 5/2, 7/2 and 9/2. Since the ion beams used in the experiments must be expected to contain long-lived excited states also from excited configurations, additional cross-section calculations were performed for the second-lowest term, $5d^5 \; ^6{\rm S}_{J}$, $J$=5/2, and for the $^4$F term, $5d^3 6s^2 \; ^4{\rm F}_{J}$, with $J$ = 3/2, 5/2, 7/2 and 9/2. Given the complexity of the electronic structure of W$^+$ the calculations reproduce the main features of the experimental cross section quite well.
description: 23 pages, 7 figures, 1 table: Accepted for publication in J. Phys. B: At. Mol. & Opt. Phys
Stochastic drift in discrete waves of non-locally interacting-particles
Creators: name: Sontag, Andrei
name: Rogers, Tim
name: Yates, Christian A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantitative Methods (q-bio.QM)
subject: Physics and Society (physics.soc-ph)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: In this paper, we investigate a generalised model of $N$ particles undergoing second-order non-local interactions on a lattice. Our results have applications across many research areas, including the modelling of migration, information dynamics and Muller's ratchet -- the irreversible accumulation of deleterious mutations in an evolving population. Strikingly, numerical simulations of the model are observed to deviate significantly from its mean-field approximation even for large population sizes. We show that the disagreement between deterministic and stochastic solutions stems from finite-size effects that change the propagation speed and cause the position of the wave to fluctuate. These effects are shown to decay anomalously as $(\log N)^{-2}$ and $(\log N)^{-3}$, respectively -- much slower than the usual $N^{-1/2}$ factor. Our results suggest that the accumulation of deleterious mutations in a Muller's ratchet and the loss of awareness in a population may occur much faster than predicted by the corresponding deterministic models. The general applicability of our model suggests that this unexpected scaling could be important in a wide range of real-world applications.
description: 14 pages, 9 figures
Effective microscopic models for sympathetic cooling of atomic gases
Creators: name: Onofrio, Roberto
name: Sundaram, Bala
Publisher: name: arXiv
Year: 2015
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Thermalization of a system in the presence of a heat bath has been the subject of many theoretical investigations especially in the framework of solid-state physics. In this setting, the presence of a large bandwidth for the frequency distribution of the harmonic oscillators schematizing the heat bath is crucial, as emphasized in the Caldeira-Leggett model. By contrast, ultracold gases in atomic traps oscillate at well-defined frequencies and therefore seem to lie outside the Caldeira-Leggett paradigm. We introduce interaction Hamiltonians which allow us to adapt the model to an atomic physics framework. The intrinsic nonlinearity of these models differentiates them from the original Caldeira-Leggett model and calls for a nontrivial stability analysis to determine effective ranges for the model parameters. These models allow for molecular dynamics simulations of mixtures of ultracold gases, which is of current relevance for optimizing sympathetic cooling in degenerate Bose-Fermi mixtures.
description: 14 pages, 7 figures
The HI supershell GS 118+01-44 and its role in the interstellar medium
Creators: name: Suad, L. A.
name: Cichowolski, S.
name: Noriega-Crespo, A.
name: Arnal, E. M.
name: Testori, J. C.
name: Flagey, N.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We carry out a multiwavelength study to characterize the HI supershell designated GS 118+01-44, and to analyse its possible origin. A multiwavlength study has been carried out to study the supershell and its environs. We performed an analysis of the HI, CO, radio continuum, and infrared emission distributions. The Canadian Galactic Plane Survey (CGPS) HI data reveals that GS 118+01-44 is centred at (l, b) = (117.7, 1.4) with a systemic velocity of -44.3 km/s. According to Galactic rotation models this structure is located at 3.0 +- 0.6 kpc from the Sun. There are several HII regions and three supernova remnants (SNRs) catalogued in the region. On the other hand, the analysis of the temperature spectral index distribution shows that in the region there is a predominance of non-thermal emission. Infrared emission shows that cool temperatures dominate the area of the supershell. Concerning the origin of the structure, we found that even though several OB stars belonging to Cas OB5 are located in the interior of GS 118+01-44, an analysis of the energy injected by these stars through their stellar winds indicates that they do not have sufficient energy to create GS 118+01-44. Therefore, an additional energy source is needed to explain the genesis of GS 118+01-44. On the other hand, the presence of several HII regions and young stellar object candidates in the edges of GS 118+01-44 shows that the region is still active in forming new stars.
description: 11 pages, 11 figures, accepted for publication in A&A
A Generic Slice of the Moduli Space of Line Arrangements
Creators: name: Ascher, Kenneth
name: Gallardo, Patricio
Publisher: name: arXiv
Year: 2016
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: We study the compactification of the locus parametrizing lines with a fixed intersection to a given line, inside the moduli space of line arrangements in the projective plane constructed for weight one by Hacking-Keel-Tevelev and Alexeev for general weights. We show that this space is smooth, with normal crossing boundary, and that it has a morphism to the moduli space of marked rational curves which can be understood as a natural continuation of the blow up construction of Kapranov. In addition, we prove that it is isomorphic to a closed subvariety inside a non-reductive Chow quotient. The parametrized objects are surfaces with broken lines, whose dual graphs are rooted trees with possibly repeated markings.
description: Improved exposition and various corrections made
Framing Perceptions of Violence against Women in Film: Les Silences du Palais and Incendies
Creators: name: Bernard-Hoverstad, Anna
Publisher: name: University of North Carolina at Chapel Hill
Year: 2013

description: Framing Perceptions of Violence against Women in Film: Les Silences du Palais and Incendies (Under the direction of Dominique D. Fisher) This thesis focuses on how contemporary Francophone films visually represent violence against women, and explores how sexual violence functions to continue the subjugation and systematic victimization of women. I examine how Moufida Tlatli's Les Silences du Palais and Denis Villeneuve's Incendies approach the subject and portrayal of rape within the greater narrative of the film. The two films, quite different in their premise and setting, find commonality as they both treat and depict rape and family dynamics. As such, my goal is to evaluate how the historical contexts of the films affect the portrayal of the violent act and how it is committed, and I consider questions about the viewer's perceptions of the perpetrators intentions might nuance their reactions to the rape scene, as well as to the film as a whole.
Classical Limit of Black Hole Quantum N-Portrait and BMS Symmetry
Creators: name: Dvali, Gia
name: Gomez, Cesar
name: Lüst, Dieter
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Black hole entropy, denoted by N, in (semi)classical limit is infinite. This scaling reveals a very important information about the qubit degrees of freedom that carry black hole entropy. Namely, the multiplicity of qubits scales as N, whereas their energy gap and their coupling as 1/N. Such a behavior is indeed exhibited by Bogoliubov-Goldstone degrees of freedom of a quantum-critical state of N soft gravitons (a condensate or a coherent state) describing the black hole quantum portrait. They can be viewed as the Goldstone modes of a broken symmetry acting on the graviton condensate. In this picture Minkowski space naturally emerges as a coherent state of infinite-N gravitons of infinite wavelength and it carries an infinite entropy. In this paper we ask what is the geometric meaning (if any) of the classical limit of this symmetry. We argue that the infinite-N limit of Bogoliubov-Goldstone modes of critical graviton condensate is described by recently-discussed classical BMS super-translations broken by the black hole geometry. However, the full black hole information can only be recovered for finite N, since the recovery time becomes infinite in classical limit in which N is infinite.
description: 15 pages, Latex
An Adaptive Framework for Optimized Passenger Flow in Urban Public Transportation Networks Using Deep Learning
Creators: name: SUTOPO, RICKY
Publisher: name: Monash University
Year: 2023
Subjects: Artificial intelligence not elsewhere classified
Public transport

description: Intelligent transportation system (ITS) plays a critical role in modernizing the transportation network. However, practical applications of ITS itself pose a multitude of technological hurdles to address. Especially with the rapid rate of worldwide urbanization, the volume of vehicles has increased significantly. Transport operators always seek out solutions to cope with this issue without affecting their timely service and minimizing their operating costs simultaneously. This research aims to design an adaptive and optimized passenger flow framework to achieve both objectives, which comprises three phases: passenger counting, passenger flow forecasting, and vehicle scheduling.
Photonic Maxwell's demon
Creators: name: Vidrighin, Mihai D.
name: Dahlsten, Oscar
name: Barbieri, Marco
name: Kim, M. S.
name: Vedral, Vlatko
name: Walmsley, Ian A.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We report an experimental realisation of Maxwell's demon in a photonic setup. We show that a measurement at the single-photon level followed by a feed-forward operation allows the extraction of work from intense thermal light into an electric circuit. The interpretation of the experiment stimulates the derivation of a new equality relating work extraction to information acquired by measurement. We derive a bound using this relation and show that it is in agreement with the experimental results. Our work puts forward photonic systems as a platform for experiments related to information in thermodynamics.
description: 8 pages, 3 figures
Quantum Sensing of Single Phonons via Phonon Drag in Two-Dimensional Materials
Creators: name: Kefayati, Ali
name: Bird, Jonathan P.
name: Perebeinos, Vasili
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The capacity to electrically detect phonons, ultimately at the single-phonon limit, is a key requirement for many schemes for phonon-based quantum computing, so-called quantum phononics. Here, we predict that by exploiting the strong coupling of their electrons to surface-polar phonons, van der Waals heterostructures can offer a suitable platform for phonon sensing, capable of resolving energy transfer at the single-phonon level. The geometry we consider is one in which a drag momentum is exerted on electrons in a graphene layer, by a single out-of-equilibrium phonon in a dielectric layer of hexagonal boron nitride, giving rise to a measurable induced voltage ($V_{\rm drag}$). Our numerical solution of the Boltzmann Transport Equation shows that this drag voltage can reach a level of a few hundred microvolts per phonon, well above experimental detection limits. Furthermore, we predict that $V_{\rm drag}$ should be highly insensitive to the mobility of carriers in the graphene layer and to increasing the temperature to at least 300 K, offering the potential of a versatile material platform for single-phonon sensing.
description: 13 pages, 6 figures
How Large is $A_g(\mathbb{F}_q)$?
Creators: name: Lipnowski, Michael
name: Tsimerman, Jacob
Publisher: name: arXiv
Year: 2015
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics

description: Let $B(g,p)$ denote the number of isomorphism classes of $g$-dimensional abelian varieties over the finite field of size $p.$ Let $A(g,p)$ denote the number of isomorphism classes of principally polarized $g$ dimensional abelian varieties over the finite field of size $p.$ We derive upper bounds for $B(g,p)$ and lower bounds for $A(g,p)$ for $p$ fixed and $g$ increasing. The extremely large gap between the lower bound for $A(g,p)$ and the upper bound $B(g,p)$ implies some statistically counterintuitive behavior for abelian varieties of large dimension over a fixed finite field.
description: 38 pages
Negligibility of small divisor effects in the normal form theory for nearly-integrable Hamiltonians with decaying non-autonomous perturbations
Creators: name: Fortunati, Alessandro
name: Wiggins, Stephen
Publisher: name: arXiv
Year: 2015
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: Primary: 70H08, Secondary: 37J40, 37J25

description: The paper deals with the problem of the existence of a normal form for a nearly-integrable real-analytic Hamiltonian with aperiodically time-dependent perturbation decaying (slowly) in time. In particular, in the case of an isochronous integrable part, the system can be cast in an exact normal form, regardless of the properties of the frequency vector. The general case is treated by a suitable adaptation of the finite order normalization techniques usually used for Nekhoroshev arguments. The key point is that the so called "geometric part" is not necessary in this case. As a consequence, no hypotheses on the integrable part are required, apart from analyticity. The work, based on two different perturbative approaches developed by A.Giorgilli et al., is a generalisation of the techniques used by the same authors to treat more specific aperiodically time-dependent problems.
description: 16 pages
Ultrafast Response of Monolayer Molybdenum Disulfide (MoS2) Photodetectors
Creators: name: Wang, Haining
name: Zhang, Changjian
name: Chan, Weimin
name: Tiwari, Sandip
name: Rana, Farhan
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The strong light emission and absorption exhibited by single atomic layer transitional metal dichalcogenides in the visible to near-infrared wavelength range makes them attractive for optoelectronic applications. In this work, using two-pulse photovoltage correlation technique, we show that monolayer molybdenum disulfide photodetector can have intrinsic response times as short as 3 ps implying photodetection bandwidths as wide as 300 GHz. The fast photodetector response is a result of the short electron-hole and exciton lifetimes in this material. Recombination of photoexcited carriers in most two-dimensional metal dichalcogenides is dominated by non-radiative processes, most notable among which is Auger scattering. The fast response time, and the ease of fabrication of these devices, make them interesting for low-cost ultrafast optical communication links.
description: 14 pages, 3 figures, 5 Supplementary Notes
Socioeconomic Status and Well-Being During COVID-19: A Resource Based Examination
Creators: name: Zhou, Le
name: Wanberg, Connie
name: Csillag, Borbala
name: Pollard, Michael
name: Douglass, Richard
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences
subject: Conservation of resources
subject: COVID-19
subject: Socioeconomic status
subject: Well-being

description: Welcome to the OSF site for the paper Wanberg, Csillag, Douglass, Zhou, & Pollard, Socioeconomic Status and Well-Being During COVID-19: A Resource Based Examination, Journal of Applied Psychology. To find syntax files for primary analyses, and syntax and tables for supplementary analyses for this paper, please click the "Files" folder to the left. Then, choose "Archive of OSF Storage"
X-ray Properties of NGC 253's Starburst-Driven Outflow
Creators: name: Lopez, Sebastian
name: Lopez, Laura A.
name: Nguyen, Dustin D.
name: Thompson, Todd A.
name: Mathur, Smita
name: Bolatto, Alberto D.
name: Vulic, Neven
name: Sardone, Amy
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We analyze image and spectral data from $\approx$365~ks of observations from the {\it Chandra} X-ray Observatory of the nearby, edge-on starburst galaxy NGC 253 to constrain properties of the hot phase of the outflow. We focus our analysis on the $-$1.1 to $+$0.63 kpc region of the outflow and define several regions for spectral extraction where we determine best-fit temperatures and metal abundances. We find that the temperatures and electron densities peak in the central $\sim$250 pc region of the outflow and decrease with distance. These temperature and density profiles are in disagreement with an adiabatic spherically expanding starburst wind model and suggest the presence of additional physics such as mass loading and non-spherical outflow geometry. Our derived temperatures and densities yield few-Myr cooling times in the nuclear region, which may imply that the hot gas can undergo bulk radiative cooling as it escapes along the minor axis. Our metal abundances of O, Ne, Mg, Si, S, and Fe all peak in the central region and decrease with distance along the outflow, with the exception of Ne which maintains a flat distribution. The metal abundances indicate significant dilution outside of the starburst region. We also find estimates on the mass outflow rates which are $2.8\:M_{\odot}/\rm{yr}$ in the northern outflow and $3.2\:M_{\odot}/\rm{yr}$ in the southern outflow. Additionally, we detect emission from charge exchange and find it has a significant contribution ($20-42$\%) to the total broad-band ($0.5-7$ keV) X-ray emission in the central and southern regions of the outflow.
description: 15 pages, 9 figures; submitted (19 September 2022), accepted ApJ (22 November 2022)
Tournament a study of the opinions of Ivy League men's basketball student-athletes and coaches on a potential post-season conference
Creators: name: Pogach, Andrew A.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2006

description: The Ivy League is the only NCAA Division I conference that does not sponsor a basketball post season championship. Missed class time and increased expenses were cited as the main reasons why a tournament has not been held in the past. Student-athletes and coaches of all eight Ivy men's basketball teams completed surveys asking questions on whether they favored adding a conference tournament. Overall, 76% were in favor of a postseason tournament, and most believed the addition of a tournament would provide an opportunity for additional games (84%) and increased television exposure (82%), while not jeopardizing academic success (67%). Coaches and student-athletes selected having each tournament game played on individual campus sites as their most preferable tournament location (53%). A traditional eight-team bracket with no byes was their most favorable tournament format option (59%).
Fate of the Wiedemann-Franz law near quantum critical points of electron systems in solids
Creators: name: Khodel, V. A.
name: Clark, J. W.
name: Shaginyan, V. R.
name: Zverev, M. V.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We introduce and analyze two different scenarios for violation of the Wiedemann-Franz law in strongly correlated electron systems of solids, close to a topological quantum critical point (TQCP) where the density of states $N(0)$ diverges. The first, applicable to the Fermi-liquid (FL) side of the TQCP, involves a transverse zero-sound collective mode that opens a new channel for the thermal conductivity, thereby enhancing the Lorenz number $L(0)$ relative to the value $L_0=π^2k^2_B/3e^2$ dictated by conventional FL theory. The second mechanism for violation of the WF law, relevant to the non-Fermi-liquid (NFL) side of the TQCP, involves the formation of a flat band and leads instead to a reduction of the Lorenz number.
description: 7 pages, 1 figure
Loop-current charge density wave driven by long-range Coulomb repulsion on the kagome lattice
Creators: name: Dong, Jin-Wei
name: Wang, Ziqiang
name: Zhou, Sen
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Recent experiments on vanadium-based nonmagnetic kagomé metals $A$V$_3$Sb$_5$ ($A=$ K, Rb, Cs) revealed evidence for possible spontaneous time-reversal symmetry (TRS) breaking in the charge density wave (CDW) ordered state. The long-sought-after quantum order of loop currents has been suggested as a candidate for the TRS breaking state. However, a microscopic model for the emergence of the loop-current CDW due to electronic correlations is still lacking. Here, we calculate the susceptibility of the real and imaginary bond orders on the kagomé lattice near van Hove filling, and reveal the importance of next-nearest-neighbor Coulomb repulsion $V_2$ in triggering the instability toward imaginary bond ordered CDW. The concrete effective single-orbital $t$-$V_1$-$V_2$ model on the kagomé lattice is then studied, where $t$ and $V_1$ are the hopping and Coulomb repulsion on the nearest-neighbor bonds. We obtain the mean-field ground states, analyze their properties, and determine the phase diagram in the plane spanned by $V_1$ and $V_2$ at van Hove filling. The region dominated by $V_1$ is occupied by a $2a_0 \times 2a_0$ real CDW insulator with the inverse of Star-of-David (ISD) bond configuration. Increasing $V_2$ indeed drives a first-order transition from ISD to stabilized loop-current insulators that exhibit four possible current patterns of different topological properties, leading to orbital Chern insulators. We then extend these results away from van Hove filling and show that electron doping helps the stabilization of loop currents, and gives rise to doped orbital Chern insulators with emergent Chern Fermi pockets carrying large Berry curvature and orbital magnetic moment. Our findings provide a concrete model realization of the loop-current Chern metal at the mean-field level for the TRS breaking normal state of the kagomé superconductors.
description: 12 pages, 7 figures
Centrality dependence of multistrange baryon production in high-energy heavy-ion collisions
Creators: name: Arakelyan, G. H.
name: Merino, C.
name: Shabelski, Yu. M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider the experimental data on the production of strange Lambdas, and multistrange baryons (Xi, Omega), and antibaryons, on nuclear targets, at the energy region from SPS up to LHC, in the framework of the Quark-Gluon String Model. One remarkable result of this analysis is the significant dependence on the centrality of the collision of the experimental ratios bar(Xi)+/bar(Lambda) and bar(Omega)+/bar(Lambda) ratios in heavy-ion collisions, at SPS energies.
description: 4 pages, 2 figures, 1 table Contribution to the 51th International Symposium on Multiparticle Dynamics (ISMD2022), Pitlochry, Scotland, UK, July 31st-August 5th (2022)
Code Execution in Peer Review
Creators: name: Nüst, Daniel
name: Seibold, Heidi
name: Eglen, Stephen
name: Schulz-Vanheyden, Lea
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Physical Sciences and Mathematics
subject: Computer Sciences
subject: Software Engineering

description: Research idea: survey the practices of code execution during peer review across all disciplines, journals, and conferences. More information in https://osf.io/zasmf/
Light Rings around Five Dimensional Stationary Black Holes and Naked Singularities
Creators: name: Tavlayan, Aydin
name: Tekin, Bayram
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The existence of light rings in a spacetime is closely related to the existence of black hole horizons and observables such as the ringdown and the shadow. Black holes, compared to nonvacuum ultracompact objects, have rather unique environments. To this aim, recently [P.V.P. Cunha and C.A.R. Herdeiro, Phys. Rev. Lett. \textbf{124}, 181101 (2020)] topological arguments, independent of the underlying gravity theory, were developed to prove the existence of unstable light rings outside the Killing horizon of {\it four} dimensional asymptotically flat, stationary, axisymmetric, nonextremal black holes. Here we extend these arguments to five-dimensional stationary black holes. Generically in five dimensions, there are two possible conserved angular momenta, hence the four-dimensional discussion does not extend verbatim to five dimensions; nevertheless, we prove that there is a light ring for each rotation sense for a stationary black hole. We give the static and the Myers-Perry rotating black holes as examples. We also show that when the horizon of the black hole disappears and the singularity becomes naked, only one of the light rings survives; a similar phenomenon also occurs in four dimensions which might allow testing the cosmic censorship hypothesis.
description: 11 pages, 7 figures, v2 matches the published version
title: “Follow your bliss” — Jesse Enkamp and Iain Abernethy Talking about Karate
Creators: name: Abernethy, Iain
name: Enkamp, Jesse
name: Kuhn, Peter
Publisher: name: Journal of Martial Arts Research
Year: 2019

description: For this JOMAR | Interview we decided to combine Iain’s and Jesse’s talks from 2013 and 2018 in order to show both development and consistency in their perspectives on Karate. But this is not the only reason for this JOMAR | Interview’s focus. What is addressed between the lines is the fascinating journey an ancient Asian martial art took from the Far East across America to Europe and back again over the last hundred years — and this journey is still going on. What we can study here is kind of a transcultural flow in which the flowing subject is de- and reconstructed by millions of people practicing, teaching, and researching on it.
description: Journal of Martial Arts Research, Vol 2 No 1 (2019): Contributions 2019
Boosting Few-shot Fine-grained Recognition with Background Suppression and Foreground Alignment
Creators: name: Zha, Zican
name: Tang, Hao
name: Sun, Yunlian
name: Tang, Jinhui
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Few-shot fine-grained recognition (FS-FGR) aims to recognize novel fine-grained categories with the help of limited available samples. Undoubtedly, this task inherits the main challenges from both few-shot learning and fine-grained recognition. First, the lack of labeled samples makes the learned model easy to overfit. Second, it also suffers from high intra-class variance and low inter-class differences in the datasets. To address this challenging task, we propose a two-stage background suppression and foreground alignment framework, which is composed of a background activation suppression (BAS) module, a foreground object alignment (FOA) module, and a local-to-local (L2L) similarity metric. Specifically, the BAS is introduced to generate a foreground mask for localization to weaken background disturbance and enhance dominative foreground objects. The FOA then reconstructs the feature map of each support sample according to its correction to the query ones, which addresses the problem of misalignment between support-query image pairs. To enable the proposed method to have the ability to capture subtle differences in confused samples, we present a novel L2L similarity metric to further measure the local similarity between a pair of aligned spatial features in the embedding space. What's more, considering that background interference brings poor robustness, we infer the pairwise similarity of feature maps using both the raw image and the refined image. Extensive experiments conducted on multiple popular fine-grained benchmarks demonstrate that our method outperforms the existing state of the art by a large margin. The source codes are available at: https://github.com/CSer-Tang-hao/BSFA-FSFG.
description: Accepted to IEEE Transactions on Circuits and Systems for Video Technology (TCSVT) 2023
Dark matter and muon $(g-2)$ in local $U(1)_{L_μ-L_τ}$-extended Ma Model
Creators: name: Baek, Seungwon
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider right-handed neutrino dark matter $N_1$ in local $U(1)_{L_μ-L_τ}$-extended Ma model. With the light $U(1)_{μ-τ}$ gauge boson ($m_{Z'} \sim {\cal O}(100)$ MeV) and small $U(1)_{μ-τ}$ gauge coupling ($g_{Z'}\sim 10^{-4}-10^{-3}$) which can accommodate the muon $(g-2)$ anomaly and is still allowed by other experimental constraints, we show that we can get correct relic density of dark matter for wide range of dark matter mass ($M_1 \sim 10-100$ GeV), although the gauge coupling constant $g_{Z'}$ is small. This is due to the fact that the annihilation cross section of dark matter pair is enhanced by $M_1^4/m_{Z'}^4$ in the processes $N_1 N_1 \to Z' Z'$ or $N_1 N_1 \to Z' H_2$. We also consider the constraints from direct detection, collider searches.
description: 11 pages, 3 figures
Constraining the Contribution of Galaxies and Active Galactic Nuclei to Cosmic Reionization
Creators: name: Yoshiura, Shintaro
name: Hasegawa, Kenji
name: Ichiki, Kiyotomo
name: Tashiro, Hiroyuki
name: Shimabukuro, Hayato
name: Takahashi, Keitaro
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Understanding the detailed process of cosmic reionization is one of the remaining problems in astrophysics and cosmology. Here we construct a model of cosmic reionization that includes contribution from high-$z$ galaxies and active galactic nuclei (AGNs), and calculate the reionization and thermal histories with the model. To keep the model to be general and realistic, we vary the escape fraction of ionizing photons, $f_{\rm esc}$, and the faint-end slope of the AGN luminosity function at high redshifts, $α_{\rm hz}$, within the constraints from the observed cosmic star formation history and the observed bright-end UV luminosity functions at $z \leq 6$. Additionally, we model the spectral energy distribution (SED) of AGNs which depends on the Eddington ratio and the black-hole mass. By comparing the computed reionization histories with the observed \ion{H}{i} fractions and the optical depth for Thomson scattering from Planck, we find that $α_{\rm hz} > -1.5$ and $f_{\rm esc} < 0.15$ are favored when we employ the bright-end luminosity function obtained by Giallongo et al. Our result suggests that an AGN-dominated model with the abundance of faint-AGNs being as large as the estimate by Giallongo et al. is allowed only if the contribution from high-z galaxies is almost negligible, while a galaxy-dominant model is also allowed. We also find that the shape of SED has a significant impact on the thermal history. Therefore it is expected that measurements of the thermal state of the IGM provide useful information on properties of ionizing sources.
description: 14 pages, 14 figures, accepted to MNRAS
Operator analysis of effective spin-flavor interactions for L=1 excited baryons
Creators: name: Willemyns, Cintia
name: Schat, Carlos
Publisher: name: arXiv
Year: 2015
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We match the non-relativistic quark model, with both flavor dependent and flavor independent effective quark-quark interactions, to the spin-flavor operator basis of the 1/Nc expansion for the L=1 non-strange baryons. We obtain analytic expressions for the coefficients of the 1/Nc operators in terms of radial integrals that depend on the shape and relative strength of the spin-spin, spin-orbit and tensor interactions of the model, which are left unspecified. We obtain several new, parameter-free relations between the seven masses and the two mixing angles that can discriminate between different spin-flavor structures of the effective quark-quark interaction. We discuss in detail how a general parametrization of the mass matrix depends on the mixing angles and is constrained by the assumptions on the effective quark-quark interaction. We find that, within the present experimental uncertainties, consistency with the best values of the mixing angles as determined by a recent global fit to masses and decays does not exclude any of the two most extreme possibilities of flavor dependent (independent) quark-quark interactions, as generated by meson (gluon) exchange interactions.
description: 36 pages, 9 figures
Linker Code Size Optimization for Native Mobile Applications
Creators: name: Liu, Gai
name: Farooq, Umar
name: Zhao, Chengyan
name: Liu, Xia
name: Sun, Nian
Publisher: name: arXiv
Year: 2022
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences

description: Modern mobile applications have grown rapidly in binary size, which restricts user growth and hinders updates for existing users. Thus, reducing the binary size is important for application developers. Recent studies have shown the possibility of using link-time code size optimizations by re-invoking certain compiler optimizations on the linked intermediate representation of the program. However, such methods often incur significant build time overhead and require intrusive changes to the existing build pipeline. In this paper, we propose several novel optimization techniques that do not require significant customization to the build pipeline and reduce binary size with low build time overhead. As opposed to re-invoking the compiler during link time, we perform true linker optimization directly as optimization passes within the linker. This enables more optimization opportunities such as pre-compiled libraries that prior work often could not optimize. We evaluate our techniques on several commercial iOS applications including NewsFeedApp, ShortVideoApp, and CollaborationSuiteApp, each with hundreds of millions of daily active users. Our techniques on average achieve 18.4% binary size reduction across the three commercial applications without any user-perceivable performance degradations.
Prospective clinical trial of a new press-over crown system
Creators: name: Conard, Kathryn L.
Publisher: name: University of North Carolina at Chapel Hill
Year: 2010

description: Porcelain-fused-to-metal (PFM) and all-ceramic alternatives to metal alloy crowns are preferred in esthetically-oriented communities. When strength is of concern, the PFM crown is an accepted historical reference. Pressed-on-metal (POM) crowns are PFM restorations produced by an alternative method. Their advantages include durability, reduced abrasion, reduced porosity, and pragmatic advantages in mass production. Strong, predictable, wear-resistant, well-fitting, esthetic POM crowns may offer significant advantages over conventional PFMs. This study's aim was to evaluate two-year crown survivability. It required six clinical visits. Evaluation was planned at six, 12 and 24 months after crown cementation using CDA and USPHS quality evaluations. Follow-up evaluations continue for this IRB-approved study, but POM technology has been favorable with few adverse events. Results are 36 patients treated with 40 crowns with good to very good esthetics, veneer porcelain with reproducible quality, lacking surface porosity at the metal-ceramic interface, no voids and acceptable to satisfactory marginal adaptation.
H$_α$ line as an indicator of envelope presence around the Cepheid Polaris Aa ($α~ UMi$)
Creators: name: Usenko, I. A.
name: Miroshnichenko, A. S.
name: Klochkova, V. G.
name: Tavolzhanskaya, N. S.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present the results of the radial velocity ($RV$) measurements of metallic lines as well as H$_α$ (H$_β$) obtained in 55 high-resolution spectra of the Cepheid $α$ UMi (Polaris Aa) in 1994-2010. While the $RV$ amplitudes of these lines are roughly equal, their mean $RV$ begin to differ essentially with growth of the Polaris Aa pulsational activity. This difference is accompanied by the H$_α$ line core asymmetries on the red side mainly (so-called knife-like profiles) and reaches 8-12 km/s in 2003 with a subsequent decrease to 1.5-2 km/s. We interpret a so unusual behaviour of the H$_α$ line core as dynamical changes in the envelope around Polaris Aa.
description: 5 pages, 6 figures, 1 table
Tracking online searches for emotional wellbeing concerns and coping strategies in the UK during the COVID-19 pandemic: a Google Trends analysis
Creators: name: Evans, Hannah
name: John, Ann
name: Knipe, Duleeka
name: Gunnell, David
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Psychiatric and Mental Health
subject: Public Health
subject: Medicine and Health Sciences
subject: Epidemiology
subject: Mental and Social Health

description: Background: The COVID-19 pandemic is the largest acute public health emergency of this century. Government intervention to contain the virus focuses on non-pharmacological procedures. As the situation develops, the impact of these measures on mental health and coping strategies in individuals and the population is unknown. Methods: We used Google Trends data (01 Jan 2020 to 09 Jun 2020) to explore the changing pattern of public concern in response to government measures as indexed by changes in search frequency for topics related to mental distress as well as coping and resilience. We explored the changes of specific topics in Google trends within the UK in relation to key dates. In addition, we examined search terms that experienced the most marked rises in search frequency during the pandemic.
Status achieved in an organization -- rank dynamics
Creators: name: Wołoszyn, Maciej
name: Kułakowski, Krzysztof
Publisher: name: arXiv
Year: 2022
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: A new model of an evolution of ranks of employees due to staff turnover in an organization is designed. If the rank is determined only by the performance, the rank shift of incumbents due to the turnover is proportional to the initial rank: the status of high staff is reduced only slightly. This effect that has been observed in the literature. However, if the status also depends on some other variable, the positions of high staff may be greatly deteriorated. In that case, the effect depends nonlinearly on the time $τ$ between subsequent replacements of staff.
description: 10 pages, 6 figures
Isotropic Brownian motions over complex fields as a solvable model for May-Wigner stability analysis
Creators: name: Ipsen, J. R.
name: Schomerus, H.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We consider matrix-valued stochastic processes known as isotropic Brownian motions, and show that these can be solved exactly over complex fields. While these processes appear in a variety of questions in mathematical physics, our main motivation is their relation to a May-Wigner-like stability analysis, for which we obtain a stability phase diagram. The exact results establish the full joint probability distribution of the finite-time Lyapunov exponents, and may be used as a starting point for a more detailed analysis of the stability-instability phase transition. Our derivations rest on an explicit formulation of a Fokker-Planck equation for the Lyapunov exponents. This formulation happens to coincide with an exactly solvable class of models of the Calgero-Sutherland type, originally encountered for a model of phase-coherent transport. The exact solution over complex fields describes a determinantal point process of biorthogonal type similar to recent results for products of random matrices, and is also closely related to Hermitian matrix models with an external source.
description: 14 pages
SYMBIOTIC RELATIONSHIP REVISITED: A STUDY ON THE IMPACT OF MASS MEDIA ON TERRORISM IN THE TRANSATLANTIC REGION
Creators: name: Shuaibi, Nourah
Publisher: name: University of North Carolina at Chapel Hill Graduate School
Year: 2015
Subjects: subject: Political science
subject: FOS: Political science

description: The mass media have had a strong presence in publicizing acts of terror throughout regions where such activities can be seen. Since the late 1960s scholars agreed on the existence of a relationship between mass media and terrorism, which they called `a symbiotic relationship'. However, minimal efforts have been dedicated to empirical studies on the impact of terrorism intensity due to media coverage. This research set out to examine the literature to support the impact on acts of terror through mass communication. The study concludes that there is a lack of empirical evidence to support the correlation due to outdated approaches to the matter in question. The existing data is limited to the period until 2005. This thesis provides a refurbished model to collect recent data from 2005 to the present. The renovated model shows promise to establishing a stronger correlation for this symbiotic relationship.
Distinguishing a Slowly Accelerating Black Hole by Differential Time Delays of Images
Creators: name: Ashoorioon, Amjad
name: Poshteh, Mohammad Bagher Jahani
name: Mann, Robert B.
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 - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Accelerating supermassive black holes, connected to cosmic strings, could contribute to structure formation and get captured by galaxies if their velocities are small. This would mean that the acceleration of these black holes is small too. Such a slow acceleration has no significant effect on the shadow of such supermassive black holes. We also show that, for slowly accelerating black holes, the angular position of images in the gravitational lensing effects do not change significantly. We propose a method to observe the acceleration of these black holes through the gravitational lensing. The method is based on the observation that differential time delays associated with the images are substantially different with respect to the case of non-accelerating black holes.
description: 5 pages, 3 figures, matched the published version in PRL. arXiv admin note: substantial text overlap with arXiv:2110.13132
Atomic Scale Visualization of Quantum Interference on a Weyl Semimetal Surface by Scanning Tunneling Microscopy/Spectroscopy
Creators: name: Zheng, Hao
name: Xu, Su-Yang
name: Bian, Guang
name: Guo, Cheng
name: Chang, Guoqing
name: Sanchez, Daniel S.
name: Belopolski, Ilya
name: Lee, Chi-Cheng
name: Huang, Shin-Ming
name: Zhang, Xiao
name: Sankar, Raman
name: Alidoust, Nasser
name: Chang, Tay-Rong
name: Wu, Fan
name: Neupert, Titus
name: Chou, Fangcheng
name: Jeng, Horng-Tay
name: Yao, Nan
name: Bansil, Arun
name: Jia, Shuang
name: Lin, Hsin
name: Hasan, M. Zahid
Publisher: name: arXiv
Year: 2015
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Weyl semimetals may open a new era in condensed matter physics, materials science and nanotech after graphene and topological insulators. We report the first atomic scale view of the surface states of a Weyl semimetal (NbP) using scanning tunneling microscopy/spectroscopy. We observe coherent quantum interference patterns that arise from the scattering of quasiparticles near point defects on the surface. The measurements reveal the surface electronic structure both below and above the chemical potential in both real and reciprocal spaces. Moreover, the interference maps uncover the scattering processes of NbP's exotic surface states. Through comparison between experimental data and theoretical calculations, we further discover that the scattering channels are largely restricted by the orbital and/or spin texture of the surface band. The visualization of the scattering processes can help design novel transport effects and electronics on the topological surface of a Weyl semimetal.
description: Submitted October 2015