cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Fall-to-the-centre as a $\mathcal{PT}$ symmetry breaking transition
Creators: name: Sundaram, Sriram
name: Burgess, C. P.
name: O'Dell, D. H. J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: The attractive inverse square potential arises in a number of physical problems such as a dipole interacting with a charged wire, the Efimov effect, the Calgero-Sutherland model, near-horizon black hole physics and the optics of Maxwell fisheye lenses. Proper formulation of the inverse-square problem requires specification of a boundary condition (regulator) at the origin representing short-range physics not included in the inverse square potential and this generically breaks the Hamiltonian's continuous scale invariance in an elementary example of a quantum anomaly. The system's spectrum qualitatively changes at a critical value of the inverse-square coupling, and we here point out that the transition at this critical potential strength can be regarded as an example of a $\mathcal{PT}$ symmetry breaking transition. In particular, we use point particle effective field theory (PPEFT), as developed by Burgess et al [J. High Energy Phys., 2017(4):106, 2017], to characterize the renormalization group (RG) evolution of the boundary coupling under rescalings. While many studies choose boundary conditions to ensure the system is unitary, these RG methods allow us to systematically handle the richer case of nonunitary physics describing a source or sink at the origin (such as is appropriate for the charged wire or black hole applications). From this point of view the RG flow changes character at the critical inverse-square coupling, transitioning from a sub-critical regime with evolution between two real, unitary fixed points ($\mathcal{PT}$ symmetric phase) to a super-critical regime with imaginary, dissipative fixed points ($\mathcal{PT}$ symmetry broken phase) that represent perfect-sink and perfect-source boundary conditions, around which the flow executes limit-cycle evolution.
description: 15 pages, 4 figures. This article is a contribution to the proceedings for the online seminar series on Pseudo-Hermitian Hamiltonians in Quantum Physics
Modeling and Solving Graph Synthesis Problems Using SAT-Encoded Reachability Constraints in Picat
Creators: name: Zhou, Neng-Fa
Publisher: name: arXiv
Year: 2021
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences
subject: D.3.2

description: Many constraint satisfaction problems involve synthesizing subgraphs that satisfy certain reachability constraints. This paper presents programs in Picat for four problems selected from the recent LP/CP programming competitions. The programs demonstrate the modeling capabilities of the Picat language and the solving efficiency of the cutting-edge SAT solvers empowered with effective encodings.
description: In Proceedings ICLP 2021, arXiv:2109.07914
Chiral Logarithms Tamed
Creators: name: Kivel, N.
name: Polyakov, M. V.
name: Vladimirov, A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We derive non-linear recursion relations for the leading chiral logarithms (LLs). These relations not only provide a very efficient method of computation of LLs (e.g. the 33-loop contribution is calculated in a dozen of seconds on a PC) but also equip us with a powerful tool for the summation of the LLs. Our method is not limited to the chiral perturbation theory only, it is pertinent for any non-renormalizable effective field theory such as, for instance, the theory of critical phenomena, the low-energy quantum gravity, etc.
description: 4 pages
Jets and environment of microquasars
Creators: name: Zhang, Shuang-Nan
name: Hao, JingFang
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Two relativistic X-ray jets have been detected with the Chandra X-ray observatory from the black hole X-ray transient XTE J1550-564. We report a full analysis of the evolution of the two jets with a gamma-ray burst external shock model. A plausible scenario suggests a cavity outside the central source and the jets first travelled with constant velocity and then are slowed down by the interactions between the jets and the interstellar medium (ISM). The best fitted radius of the cavity is $\sim$0.36 pc on the eastern side and $\sim$0.46 pc on the western side, and the densities also show asymmetry, of $\sim$0.015 cm$^{-3}$ on the east to $\sim$0.21 cm$^{-3}$ on the west. A large scale low density region is also found in another microquasar system, H 1743-322. These results are consistent with previous suggestions that the environment of microquasars should be rather vacuous, compared to the normal Galactic environment. A generic scenario for microquasar jets is proposed, classifying the observed jets into three main categories, with different jet morphologies (and sizes) corresponding to different scales of vacuous environments surrounding them.
description: 8 pages, 4 figures, invited talk, the 8th Pacific Rim Conference on Stellar Astrophysics, 5-9 May, 2008, eds B. Soonthornthum, S. Komonjinda, K. S. Cheng and K. C. Leung
Fast and slow light in zig-zag microring resonator chains
Creators: name: Chamorro-Posada, P.
name: Fraile-Pelaez, F. J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We analyze fast and slow light transmission in a zig-zag microring resonator chain. This novel device permits the operation in both regimes. In the superluminal case, a new ubiquitous light transmission effect is found whereby the input optical pulse is reproduced in an almost simultaneous manner at the various system outputs. When the input carrier is tuned to a different frequency, the system permits to slow down the propagating optical signal. Between these two extreme cases, the relative delay can be tuned within a broad range.
From Blue Cloud to Red Sequence: Evidence of Morphological Transition Prior to Star Formation Quenching
Creators: name: Sampaio, V. M.
name: de Carvalho, R. R.
name: Ferreras, I.
name: Aragón-Salamanca, A.
name: Parker, L. C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present a study of a sample of 254 clusters from the SDSS-DR7 Yang Catalog and an auxiliary sample of field galaxies to perform a detailed investigation on how galaxy quenching depends on both environment and galaxy stellar mass. Our samples are restricted to 0.03$\leq$z$\leq$0.1 and we only consider clusters with $\rm log(M_{halo}/M_{\odot}) \geq 14$. Comparing properties of field and cluster galaxies in the Blue Cloud, Green Valley and Red Sequence, we find evidence that field galaxies in the red sequence hosted star formation events $\rm 2.1 \pm 0.7$ Gyr ago, on average, more recently than galaxies in cluster environments. Dissecting the star formation rate vs stellar mass diagram we show how morphology rapidly changes after reaching the green valley region, while the star formation rate keeps decreasing. In addition, we use the relation between location in the projected phase space and infall time to explore the time delay between morphological and specific Star Formation Rate variations. We estimate that the transition from late to early-type morphology happens in $\rm Δt_{inf} \sim$1 Gyr, whereas the quenching of star formation takes $\sim$3 Gyr. The time-scale we estimate for morphological transitions is similar to the expected for the delayed-then-rapid quenching model. Therefore, we suggest that the delay phase is characterized mostly by morphological transition, which then contributes morphological quenching as an additional ingredient in galaxy evolution.
description: 18 pages, 10 Figures, Accepted for Publication in the Monthly Notices of the Royal Astronomical Society
MPEC 2024-S185 : 2024 SU5
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 SU5

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.
Enhancement of sudden death of entanglement for driven qubits
Creators: name: Li, Jian
name: Chalapat, K.
name: Paraoanu, G. S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the recently discovered phenomena of sudden death of entanglement for a system of two qubits, each of them independently longitudinally damped by a reservoir and subjected to a continuous driving. We show that driving produces, in the interaction picture, an effective bath that has elements amounting to various extra sources of noise (transverse, thermal squeezed, thermal longitudinal). As a result, the time of sudden death decreases due to driving, which we verify as well by direct numerical calculation. We suggest that this phenomenon can be studied systematically using superconducting qubits driven by microwave fields.
description: 9 pages, 2 figures
A Logic-based Multi-agent System for Ethical Monitoring and Evaluation of Dialogues
Creators: name: Dyoub, Abeer
name: Costantini, Stefania
name: Letteri, Ivan
name: Lisi, Francesca A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: Multiagent Systems (cs.MA)
subject: FOS: Computer and information sciences
subject: I.2;I.2.11;I.2.6;I.3.8

description: Dialogue Systems are tools designed for various practical purposes concerning human-machine interaction. These systems should be built on ethical foundations because their behavior may heavily influence a user (think especially about children). The primary objective of this paper is to present the architecture and prototype implementation of a Multi Agent System (MAS) designed for ethical monitoring and evaluation of a dialogue system. A prototype application, for monitoring and evaluation of chatting agents' (human/artificial) ethical behavior in an online customer service chat point w.r.t their institution/company's codes of ethics and conduct, is developed and presented. Future work and open issues with this research are discussed.
description: In Proceedings ICLP 2021, arXiv:2109.07914
Giant Magnons and Spiky Strings on S^3 with B-field
Creators: name: Chen, Chiang-Mei
name: Tsai, Jia-Hao
name: Wen, Wen-Yu
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study solutions for a rotating string on S^3 with a background NS-NS B-field and show the existence of spiky string and giant magnon as two limiting solutions. We make a connection to the sine-Gordon model via the Polyakov worldsheet action and study the effect of B-field. In particular, we find the magnon solution can be mapped to the excitation of a fractional spin chain. We conjecture a B-deformed SYM to be the gauge theory dual to this background.
description: 22 pages, 3 figures, more references added
Geolog: Scalable Logic Programming on Spatial Data
Creators: name: Grubenmann, Tobias
name: Lehmann, Jens
Publisher: name: arXiv
Year: 2021
Subjects: subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences

description: Spatial data is ubiquitous in our data-driven society. The Logic Programming community has been investigating the use of spatial data in different settings. Despite the success of this research, the Geographic Information System (GIS) community has rarely made use of these new approaches. This has mainly two reasons. First, there is a lack of tools that tightly integrate logical reasoning into state-of-the-art GIS software. Second, the scalability of solutions has often not been tested and hence, some solutions might work on toy examples but do not scale well to real-world settings. The two main contributions of this paper are (1) the Relation Based Programming paradigm, expressing rules on relations instead of individual entities, and (2) Geolog, a tool for spatio-logical reasoning that can be installed on top of ArcMap, which is an industry standard GIS. We evaluate our new Relation Based Programming paradigm in four real-world scenarios and show that up to two orders of magnitude in performance gain can be achieved compared to the prevalent Entity Based Programming paradigm.
description: In Proceedings ICLP 2021, arXiv:2109.07914
Asymptotically self-similar propagation of the spherical ionization waves
Creators: name: Kyuregyan, A. S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: It is shown that a new type of the self-similar spherical ionization waves may exist in gases. All spatial scales and the propagation velocity of such waves increase exponentially in time. Conditions for existence of these waves are established, their structure is described and approximate analytical relationships between the principal parameters are obtained. It is notable that spherical ionization waves can serve as the simplest, but structurally complete and physically transparent model of streamer in homogeneous electric field.
description: Corrected typos, the more precise formulas are obtained
About Bernoulli's Numbers
Creators: name: Bencze, Mihaly
name: Smarandache, Florentin
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Mathematics (math.GM)
subject: FOS: Mathematics
subject: 11B68

description: In this article we present a simple proof of Borevich-Shafarevich's method to compute the sum of the first n natural numbers of the same power. We also prove several properties of Bernoulli's numbers.
description: 3 pages
Cross-Network Learning with Partially Aligned Graph Convolutional Networks
Creators: name: Jiang, Meng
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Graph neural networks have been widely used for learning representations of nodes for many downstream tasks on graph data. Existing models were designed for the nodes on a single graph, which would not be able to utilize information across multiple graphs. The real world does have multiple graphs where the nodes are often partially aligned. For examples, knowledge graphs share a number of named entities though they may have different relation schema; collaboration networks on publications and awarded projects share some researcher nodes who are authors and investigators, respectively; people use multiple web services, shopping, tweeting, rating movies, and some may register the same email account across the platforms. In this paper, I propose partially aligned graph convolutional networks to learn node representations across the models. I investigate multiple methods (including model sharing, regularization, and alignment reconstruction) as well as theoretical analysis to positively transfer knowledge across the (small) set of partially aligned nodes. Extensive experiments on real-world knowledge graphs and collaboration networks show the superior performance of our proposed methods on relation classification and link prediction.
description: 9 pages, 8 figures, KDD 2021
On the origin of approximate custodial symmetry in the Two-Higgs Doublet Model
Creators: name: Froggatt, C. D.
name: Nevzorov, R.
name: Nielsen, H. B.
name: Thompson, D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We argue that the consistent implementation of the multiple point principle (MPP) in the general non-supersymmetric two Higgs doublet model (2HDM) can lead to a set of approximate global custodial symmetries that ensure CP conservation in the Higgs sector and the absence of flavour changing neutral currents (FCNC) in the considered model. In particular the existence of a large set of degenerate vacua at some high energy scale $Λ$ caused by the MPP can result in approximate U(1) and Z(2) symmetries that suppress FCNC and CP--violating interactions in the 2HDM. We explore the renormalisation group (RG) flow of the Yukawa and Higgs couplings within the MPP inspired 2HDM with approximate custodial symmetries and show that the solutions of the RG equations are focused near quasi--fixed points at low energies if the MPP scale scale $Λ$ is relatively high. We study the Higgs spectrum and couplings near the quasi--fixed point at moderate values of $\tanβ$ and compute a theoretical upper bound on the lightest Higgs boson mass. If $Λ\gtrsim 10^{10} {GeV}$ the lightest CP--even Higgs boson is always lighter than $125 {GeV}$. When the MPP scale is low, the mass of the lightest Higgs particle can reach $180-220 {GeV}$ while its coupling to the top quark can be significantly larger than in the SM, resulting in the enhanced production of Higgs bosons at the LHC.
description: 59 pages, 8 figures, version to be published in IJMPA
Energy and Vorticity in Fast Rotating Bose-Einstein Condensates
Creators: name: Correggi, M.
name: Yngvason, J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mathematical Physics (math-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences
subject: 35Q55,47J30,76M23

description: We study a rapidly rotating Bose-Einstein condensate confined to a finite trap in the framework of two-dimensional Gross-Pitaevskii theory in the strong coupling (Thomas-Fermi) limit. Denoting the coupling parameter by $1/\eps^2$ and the rotational velocity by $Ω$, we evaluate exactly the next to leading order contribution to the ground state energy in the parameter regime $|\log\eps|\ll Ω\ll 1/(\eps^2|\log\eps|)$ with $\eps\to 0$. While the TF energy includes only the contribution of the centrifugal forces the next order corresponds to a lattice of vortices whose density is proportional to the rotational velocity.
description: 19 pages, LaTeX; typos corrected, clarifying remarks added, some rearrangements in the text
Temperature Dependence of Critical Current Fluctuations in Nb/AlO$\mathrm{_{x}}$/Nb Josephson Junctions
Creators: name: Pottorf, Shawn
name: Patel, Vijay
name: Lukens, James E.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We have measured the low frequency critical current noise in Nb/AlO$_{\mathrm{x}}$/Nb Josephson junctions. Unshunted junctions biased above the gap voltage and resistively shunted junctions biased near the critical current, $I_{c}$, have been measured. For both, the spectral density of $δI_{c}/I_{c}$, $S_{i_{c}}(f)$, is proportional to $1/f$, scales inversely as the area, $A$, and is independent of $J_{c} \equiv I_{c}/A$ over a factor of nearly 20 in $J_{c}$. For all devices measured at 4.2 K, $S_{i_{c}}$(1 Hz)$= 2.0 \pm 0.4 \cdot 10^{-12}$/Hz when scaled to A=1 $μ$m$^{2}$. We find that, from 4.2 K to 0.46 K, $S_{i_{c}}(f)$ decreases linearly with temperature.
El chaco y misiones en la narrativa de Horacio Quiroga
Creators: name: Atencio, Raquel
Publisher: name: University of British Columbia
Year: 2010

description: A mediados de 1903 Quiroga visita por primera vez Misiones, región ubicada en el norte de Argentina. Desde este momento, este territorio estará ligado al nombre de Quiroga como parte integrante de toda su existencia. En 1909 decide establecerse definitivamente en este lugar. El propósito de este trabajo es mostrar la importancia que la región de Misiones representa no sólo en la vida sino en la obra literaria de Quiroga, así como observar algunos de los temas característicos de sus cuentos. Con este fin, los relatos seleccionados no sólo tienen en común el escenario—monte chaqueñoo selva misionera—sino que por contener t . temas básicos de la obra de Quirogaj pueden al mismo tiempo servir de punto de referencia para estudiar otra serie de relatos. Esta selección se limita a cuatro cuentos específicamente. "La insolación"—monte chaqueño—"Los mensú," "El hombre muerto" y "El regreso de Anaconda" —escenarios misioneros. En el ambiente en que se mueven los personajes la naturaleza tiene un papel tan relevante como cualquiera de sus protagonistas. A través de. este estudio parcial de los cuentos de Quiroga se puede observar la importancia de la selva tropical con los elementos característicos de su clima; el abuso del hombre contra sus semejantes que en su afán de poder no le importa arriesgar la salud e incluso la vida de los demás, así como la muerte vista no como un acontecimiento extraordinario sino como el elemento al que el hombre debe enfrentarse cada día. En los relatos analizados se ha visto que Quiroga se compenetra en este escenario de tal manera, que sus relatos al mismo tiempo que nos muestran una realidad verificable, son en gran parte la narración de experiencias vividas por el autor. Se espera con esta tesis contribuir al conocimiento de la obra cuentística de Horacio Quiroga.
MPEC 2024-S186 : 2024 SV5
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 SV5

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.
Strongly Fillable Contact Manifolds and J-holomorphic Foliations
Creators: name: Wendl, Chris
Publisher: name: arXiv
Year: 2008
Subjects: subject: Symplectic Geometry (math.SG)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 32Q65; 57R17

description: We prove that every strong symplectic filling of a planar contact manifold admits a symplectic Lefschetz fibration over the disk, and every strong filling of the 3-torus similarly admits a Lefschetz fibration over the annulus. It follows that strongly fillable planar contact structures are also Stein fillable, and all strong fillings of the 3-torus are equivalent up to symplectic deformation and blowup. These constructions result from a compactness theorem for punctured J-holomorphic curves that foliate a convex symplectic manifold. We use it also to show that the compactly supported symplectomorphism group on the cotangent bundle of the 2-torus is contractible, and to define an obstruction to strong fillability that yields a non-gauge-theoretic proof of Gay's recent nonfillability result for contact manifolds with positive Giroux torsion.
description: 44 pages, 2 figures; v.3 has a few significant improvements to the main results: We now classify all strong fillings and exact fillings of T^3 (without assuming Stein), and also show that a planar contact manifold is strongly fillable if and only if all its planar open books have monodromy generated by right-handed Dehn twists. To appear in Duke Math. J
Direct and Reverse Secret-Key Capacities of a Quantum Channel
Creators: name: Pirandola, Stefano
name: Garcia-Patron, Raul
name: Braunstein, Samuel L.
name: Lloyd, Seth
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: Cryptography and Security (cs.CR)
subject: Information Theory (cs.IT)
subject: Optics (physics.optics)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We define the direct and reverse secret-key capacities of a memoryless quantum channel as the optimal rates that entanglement-based quantum key distribution protocols can reach by using a single forward classical communication (direct reconciliation) or a single feedback classical communication (reverse reconciliation). In particular, the reverse secret-key capacity can be positive for antidegradable channels, where no forward strategy is known to be secure. This property is explicitly shown in the continuous variable framework by considering arbitrary one-mode Gaussian channels.
description: 4 pages, 5 figures, REVteX
In-plane quasi-single-domain BaTiO$_3$ via interfacial symmetry engineering
Creators: name: Lee, J. W.
name: Eom, K.
name: Paudel, T. R.
name: Wang, B.
name: Lu, H.
name: Huyan, H.
name: Lindemann, S.
name: Ryu, S.
name: Lee, H.
name: Kim, T. H.
name: Yuan, Y.
name: Zorn, J. A.
name: Lei, S.
name: Gao, W.
name: Tybell, T.
name: Gopalan, V.
name: Pan, X.
name: Gruverman, A.
name: Chen, L. Q.
name: Tsymbal, E. Y.
name: Eom, C. B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The control of the in-plane domain evolution in ferroelectric thin films is not only critical to understanding ferroelectric phenomena but also to enabling functional device fabrication. However, in-plane polarized ferroelectric thin films typically exhibit complicated multi-domain states, not desirable for optoelectronic device performance. Here we report a strategy combining interfacial symmetry engineering and anisotropic strain to design single-domain, in-plane polarized ferroelectric BaTiO$_3$ thin films. Theoretical calculations predict the key role of the BaTiO$_3$ / PrScO$_3$ (110)$_O$ substrate interfacial environment, where anisotropic strain, monoclinic distortions, and interfacial electrostatic potential stabilize a single-variant spontaneous polarization. A combination of scanning transmission electron microscopy, piezoresponse force microscopy, ferroelectric hysteresis loop measurements, and second harmonic generation measurements directly reveals the stabilization of the in-plane quasi-single-domain polarization state. This work offers design principles for engineering in-plane domains of ferroelectric oxide thin films, which is a prerequisite for high performance optoelectronic devices.
Optical Properties of Superconducting Nanowire Single-Photon Detectors
Creators: name: Anant, Vikas
name: Kerman, Andrew J.
name: Dauler, Eric A.
name: Yang, Joel K. W.
name: Rosfjord, Kristine M.
name: Berggren, Karl K.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Optics (physics.optics)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: We measured the optical absorptance of superconducting nanowire single photon detectors. We found that 200-nm-pitch, 50%-fill-factor devices had an average absorptance of 21% for normally-incident front-illumination of 1.55-um-wavelength light polarized parallel to the nanowires, and only 10% for perpendicularly-polarized light. We also measured devices with lower fill-factors and narrower wires that were five times more sensitive to parallel-polarized photons than perpendicular-polarized photons. We developed a numerical model that predicts the absorptance of our structures. We also used our measurements, coupled with measurements of device detection efficiencies, to determine the probability of photon detection after an absorption event. We found that, remarkably, absorbed parallel-polarized photons were more likely to result in detection events than perpendicular-polarized photons, and we present a hypothesis that qualitatively explains this result. Finally, we also determined the enhancement of device detection efficiency and absorptance due to the inclusion of an integrated optical cavity over a range of wavelengths (700-1700 nm) on a number of devices, and found good agreement with our numerical model.
description: will appear in optics express with minor revisions
Precise timing and phase-resolved spectroscopy of the young pulsar J1617-5055 with NuSTAR
Creators: name: Hare, J.
name: Volkov, I.
name: Pavlov, G. G.
name: Kargaltsev, O.
name: Johnston, S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We report on a NuSTAR observation of the young, energetic pulsar PSR J1617-5055. Parkes Observatory 3 GHz radio observations of the pulsar (taken about 7 years before the NuSTAR observations) are also reported here. NuSTAR detected pulsations at a frequency of $f\approx14.4$ Hz ($P\approx69.44$ ms) and, in addition, the observation was long enough to measure the source's frequency derivative, $\dot{f}\approx-2.8\times10^{-11}$ Hz s$^{-1}$. We find that the pulsar shows one peak per period at both hard X-ray and radio wavelengths, but that the hard X-ray pulse is broader (having a duty cycle of $\sim 0.7$), than the radio pulse (having a duty cycle of $\sim 0.08$). Additionally, the radio pulse is strongly linearly polarized. J1617's phase-integrated hard X-ray spectrum is well fit by an absorbed power-law model, with a photon index $Γ=1.59\pm 0.02$. The hard X-ray pulsations are well described by three Fourier harmonics, and have a pulsed fraction that increases with energy. We also fit the phase-resolved NuSTAR spectra with an absorbed power-law model in five phase bins and find that the photon index varies with phase from $Γ= 1.52\pm 0.03$ at phases around the flux maximum to $Γ=1.79\pm 0.06$ around the flux minimum. Lastly, we compare our results with other pulsars whose magnetospheric emission is detected at hard X-ray energies and find that, similar to previous studies, J1617's hard X-ray properties are more similar to the MeV pulsars than the GeV pulsars.
description: Accepted for publication in ApJ
Experiment: Effects of vehicle source intensity on pedestrians' auditory and audiovisual street-crossing decisions
Creators: name: Huisman, Thirsa
name: Oberfeld, Daniel
Publisher: name: OSF
Year: 2025
Subjects: audiovisual perception
audiovisual virtual reality
auditory perception
experimental psychology
internal combustion engine vehicles
loudness
pedestrian
perceptual cues
street-crossing behavior
vehicle simulation
virtual acoustics
visual perception

description: Primary data etc. from an experiment on the effects of vehicle source intensity on street-crossing decisions based on only auditory or combined auditory and visual information
Publication: The effect of vehicle sound intensity on auditory-only time-to-collision estimation
Creators: name: Oberfeld, Daniel
name: Huisman, Thirsa
Publisher: name: OSF
Year: 2024
Subjects: audiovisual virtual reality
auditory perception
experimental psychology
intensity-arrival effect
internal combustion engine vehicles
loudness
pedestrian
perceptual cues
street-crossing behavior
time-to-collision estimation
vehicle simulation
vehicle source intensity
virtual acoustics
visual perception

description: Primary data for a manuscript on auditory time-to-collision estimation, focusing on effect of the acoustic vehicle source intensity and the type of intensity variation (blockwise vs. trial-by-trial) on these judgments.
DiscASP: A Graph-based ASP System for Finding Relevant Consistent Concepts with Applications to Conversational Socialbots
Creators: name: Li, Fang
name: Wang, Huaduo
name: Basu, Kinjal
name: Salazar, Elmer
name: Gupta, Gopal
Publisher: name: arXiv
Year: 2021
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences
subject: I.2.3

description: We consider the problem of finding relevant consistent concepts in a conversational AI system, particularly, for realizing a conversational socialbot. Commonsense knowledge about various topics can be represented as an answer set program. However, to advance the conversation, we need to solve the problem of finding relevant consistent concepts, i.e., find consistent knowledge in the "neighborhood" of the current topic being discussed that can be used to advance the conversation. Traditional ASP solvers will generate the whole answer set which is stripped of all the associations between the various atoms (concepts) and thus cannot be used to find relevant consistent concepts. Similarly, goal-directed implementations of ASP will only find concepts directly relevant to a query. We present the DiscASP system that will find the partial consistent model that is relevant to a given topic in a manner similar to how a human will find it. DiscASP is based on a novel graph-based algorithm for finding stable models of an answer set program. We present the DiscASP algorithm, its implementation, and its application to developing a conversational socialbot.
description: In Proceedings ICLP 2021, arXiv:2109.07914
Scaling Up Rate Limiting Quotas using Proxies
Creators: name: Ashlin Darius, Govindasamy
Publisher: name: Zenodo
Year: 2024
Subjects: Rate limiting
API requests
proxies
scaling
set theory
theorem
lemma
proof
non-overlapping
inclusion-exlusion principle

description: In this paper, we explore a novel approach to circumvent the constraints imposed by ratelimiting quotas on API requests. Rate limiting, a common mechanism employed by webservices, restricts the number of requests a user can make to an API within a given timeframeto ensure equitable server resource distribution and prevent abuse. This limitation poses asignificant challenge for applications requiring high-volume data access in real-time. Wepropose a method to scale up the effective rate limiting quota by employing multiple, nonoverlapping proxy servers to distribute the requests. By assigning a distinct subset of the totalrequests to each proxy, we theoretically increase the total number of requests that can bemade within the rate limiting window. We formalize this approach through a theorem andsupporting lemma, utilizing set theory to articulate and prove the efficacy of proxy-basedrequest distribution in scaling rate limiting quotas. Our method offers a pragmatic solution forapplications needing to surpass the API request thresholds set by service providers, withoutviolating the intended use policies or compromising the integrity of the web service.
Differential fast fixed-point algorithms for underdetermined instantaneous and convolutive partial blind source separation
Creators: name: Thomas, J.
name: Deville, Y.
name: Hosseini, Shahram
Publisher: name: arXiv
Year: 2008
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: This paper concerns underdetermined linear instantaneous and convolutive blind source separation (BSS), i.e., the case when the number of observed mixed signals is lower than the number of sources.We propose partial BSS methods, which separate supposedly nonstationary sources of interest (while keeping residual components for the other, supposedly stationary, "noise" sources). These methods are based on the general differential BSS concept that we introduced before. In the instantaneous case, the approach proposed in this paper consists of a differential extension of the FastICA method (which does not apply to underdetermined mixtures). In the convolutive case, we extend our recent time-domain fast fixed-point C-FICA algorithm to underdetermined mixtures. Both proposed approaches thus keep the attractive features of the FastICA and C-FICA methods. Our approaches are based on differential sphering processes, followed by the optimization of the differential nonnormalized kurtosis that we introduce in this paper. Experimental tests show that these differential algorithms are much more robust to noise sources than the standard FastICA and C-FICA algorithms.
description: this paper describes our differential FastICA-like algorithms for linear instantaneous and convolutive underdetermined mixtures
Local information transfer as a spatiotemporal filter for complex systems
Creators: name: Lizier, Joseph T.
name: Prokopenko, Mikhail
name: Zomaya, Albert Y.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Cellular Automata and Lattice Gases (nlin.CG)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We present a measure of local information transfer, derived from an existing averaged information-theoretical measure, namely transfer entropy. Local transfer entropy is used to produce profiles of the information transfer into each spatiotemporal point in a complex system. These spatiotemporal profiles are useful not only as an analytical tool, but also allow explicit investigation of different parameter settings and forms of the transfer entropy metric itself. As an example, local transfer entropy is applied to cellular automata, where it is demonstrated to be a novel method of filtering for coherent structure. More importantly, local transfer entropy provides the first quantitative evidence for the long-held conjecture that the emergent traveling coherent structures known as particles (both gliders and domain walls, which have analogues in many physical processes) are the dominant information transfer agents in cellular automata.
description: 12 pages
Les portes du sanctuaire de l’Eglise de la Visitation du Sault-au-Récollet, Montreal
Creators: name: Glen-Groarke, Marie-Andrée
Publisher: name: University of British Columbia
Year: 2010

description: L'église de la Visitation de la Bienheureuse Vierge Marie du Sault-au-Récollet, érigée en 1751, demeure actuellement la plus ancienne église de l'île de Montréal. Classée "Monument Historique" par le Ministère des Affaires Culturelles le 13 février 1975, elle attire de plus en plus l'attention des historiens de l'art par l'abondance des oeuvres façonnées par des artistes locaux. Au cours de ce mémoire, nous présenterons dans un premier chapitre un court historique de la paroisse du Sault-au-Récollet pour montrer l'importance de ce secteur de la ville dans l'évolution de la colonie; ensuite nous survolerons rapidement le développement architectural du bâtiment et reviserons sa décoration intérieure. En un second chapitre, nous procéderons â une description détaillée des portes du sanctuaire. Suivra leur étude iconographique qui tentera entre autres d'expliquer le symbolisme des bas-reliefs y figurant et cherchera la source des sujets représentés, Samson tuant le lion de Thamna et Samson emportant les portes de Gaza. Les portes du sanctuaire de La Visitation n'ont pas, jusqu'à ce jour, attiré plus que de raison l'attention des chercheurs. Depuis leur attribution â Philippe Liébert par Ramsay Traquair en 1927 et à la suite du livre de Gérard Morisset (1943) traitant de cet artiste, personne n'a pensé questionner l'auteur de ces pièces. C'est de ce problème que discutera le troisième chapitre. Ainsi â la lumière du style du sculpteur montréalais François Guernon dit Belleville que nous analyserons dans les bas-reliefs du Calvaire d'Oka et de l'église de Saint-Martin (île Jésus), nous étudierons en détail la manière de travailler se dégageant des panneaux des portes du choeur de La Visitation. De plus une courte comparaison avec deux oeuvres de Liébert aidera à exposer les raisons pour lesquelles nous croyons que François Guernon dit Belleville et non Philippe Liébert exécuta ces portes.
d=4 Attractors, Effective Horizon Radius and Fake Supergravity
Creators: name: Ferrara, S.
name: Gnecchi, A.
name: Marrani, A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider extremal black hole attractors (both BPS and non-BPS) for N=3 and N=5 supergravity in d=4 space-time dimensions. Attractors for matter-coupled N=3 theory are similar to attractors in N=2 supergravity minimally coupled to Abelian vector multiplets. On the other hand, N=5 attractors are similar to attractors in N=4 pure supergravity, and in such theories only 1\N-BPS non-degenerate solutions exist. All the above mentioned theories have a simple interpretation in the first order (fake supergravity) formalism. Furthermore, such theories do not have a d=5 uplift. Finally we comment on the "duality" relations among the attractor solutions of N\geq2 supergravities sharing the same full bosonic sector.
description: 1+47 pages, 2 Tables. v2: Eqs. (2.3),(2.4) and Footnote 3 added; minor cosmetic changes; to appear in PRD
CADE em Números PAINEL Condutas Anticompetitivas
Creators: name: Alexandre Cordeiro Macedo
name: Paulo Eduardo Silva de Oliveira
name: Vinicius Eloy dos Reis
name: William José da Conceição Marques
name: Leonardo de Oliveira Alves Sanches Lima
name: Alessandro Lustosa Seixas Pinheiro
name: Cristiane de Freitas Leal
name: Felipe Alberto Moreira
name: Helio Ribeiro da Costa
name: Jorge Luiz Hachem Vasconcelos
name: Wendel Sousa de Anchieta
name: Márcia Abrahão Moura
name: Maria Emília Machado Telles Walter
name: Rafael Timóteo de Sousa Júnior
name: Edna Dias Canedo
name: Georges Daniel Amvame Nze
name: Valério Aymore Martins
name: Adailton Amaro Nunes
name: Alessandra de Vasconcelos Sales
name: Aline Lima da Silva
name: Ana Beatriz de Sousa Monteiro
name: Ana Flavia Araújo Santana
name: André Luiz Chaves da Silva
name: Bruno Justino Garcia Praciano
name: Caroline Emanuele da Silva Sousa
name: Danilo Freire Holanda de Paiva
name: Denise Mitie Taketomi
name: Edle Marcio dos Santos Silva
name: Eduardo Drumond Soares
name: Fábio Lúcio Lopes de Mendonça
name: Felipe Evangelista dos Santos
name: Felipe Lobão Lima
name: Guilherme Pereira Paiva
name: Hugo Bartolomeu Ferreira
name: Ian Porto e Melo
name: Igor de Almeida Gentil
name: Isabela de Lima Silva
name: Italo Eduardo Dias Frota
name: Izadora Oliveira Linhares
name: Jeanne Louize Emygdio
name: Julia Jamile de Oliveira Gonçalves
name: Karen Ferreira Machado
name: Lincoln Abreu Barbosa
name: Lohana Salustiano Cardoso
name: Luiz Fernando Santos de Araujo Caduda
name: Marcelo Dos Santos Vianna
name: Marcio Junior Vieira
name: Marcos Vinicius da Silva Souza
name: Mateus Alves Dantas
name: Noely Gomes de Lima
name: Paulo Henrique Batista Rodrigues
name: Rafael de Arruda Faria
name: Renato Carauta Ribeiro
name: Rogerio de Oliveira Costa
name: Thays de Oliveira Coelho
name: Thiago Augusto Montenegro Pestana
name: Vanessa Coelho Ribeiro
name: Welber Santos de Oliveira
name: Zaquel Isaque Alves Cabral
Publisher: name: Zenodo
Year: 2022

description: Pesquisa Aplicada com fundamento no estudo de necessidades, análise informacional, concepção, prototipação e experimentação com vistas à inovação tecnológica e de processos no domínio da Defesa Econômica para o Conselho Administrativo de Defesa Econômica – Cade.
Jitter radiation: towards TeV-photons of gamma-ray bursts
Creators: name: Mao, Jirong
name: Wang, Jiancheng
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The synchrotron mechanism has the radiation limit of about 160 MeV, and it is not possible to explain the very high energy (VHE) photons that are emitted by high-energy objects. Inverse Compton scattering as a traditional process is applied for the explanation of the VHE emission. In this paper, jitter radiation, the relativistic electron radiation in the random and small-scale magnetic field, is proposed to be a possible mechanism to produce VHE photons. The jitter radiation frequency is associated with the perturbation field. The spectral index of the jitter radiation is dominated by the kinetic turbulence. We utilize the jitter radiation to explain the gamma-ray burst (GRB 190114C and GRB 180720B) VHE emissions that were recently detected by the Imaging Atmospheric Cherenkov Telescopes. We suggest that this mechanism can be applied to other kinds of VHE sources.
description: MNRAS accepted
Generating Concurrent Programs From Sequential Data Structure Knowledge Using Answer Set Programming
Creators: name: Varanasi, Sarat Chandra
name: Mittal, Neeraj
name: Gupta, Gopal
Publisher: name: arXiv
Year: 2021
Subjects: subject: Programming Languages (cs.PL)
subject: Artificial Intelligence (cs.AI)
subject: Logic in Computer Science (cs.LO)
subject: FOS: Computer and information sciences

description: We tackle the problem of automatically designing concurrent data structure operations given a sequential data structure specification and knowledge about concurrent behavior. Designing concurrent code is a non-trivial task even in simplest of cases. Humans often design concurrent data structure operations by transforming sequential versions into their respective concurrent versions. This requires an understanding of the data structure, its sequential behavior, thread interactions during concurrent execution and shared memory synchronization primitives. We mechanize this design process using automated commonsense reasoning. We assume that the data structure description is provided as axioms alongside the sequential code of its algebraic operations. This information is used to automatically derive concurrent code for that data structure, such as dictionary operations for linked lists and binary search trees. Knowledge in our case is expressed using Answer Set Programming (ASP), and we employ deduction and abduction -- just as humans do -- in the reasoning involved. ASP allows for succinct modeling of first order theories of pointer data structures, run-time thread interactions and shared memory synchronization. Our reasoner can systematically make the same judgments as a human reasoner, while constructing provably safe concurrent code. We present several reasoning challenges involved in transforming the sequential data structure into its equivalent concurrent version. All the reasoning tasks are encoded in ASP and our reasoner can make sound judgments to transform sequential code into concurrent code. To the best of our knowledge, our work is the first one to use commonsense reasoning to automatically transform sequential programs into concurrent code. We also have developed a tool that we describe that relies on state-of-the-art ASP solvers and performs the reasoning tasks involved to generate concurrent code.
description: In Proceedings ICLP 2021, arXiv:2109.07914. arXiv admin note: substantial text overlap with arXiv:2011.04045
The HI - Star Formation Connection: Open Questions
Creators: name: Meurer, Gerhardt R.
name: Wong, O. Ivy
name: Hanish, Daniel J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We show data from the Survey of Ionization in Neutral Gas Galaxies (SINGG) and Survey of Ultraviolet emission in Neutral Gas Galaxies (SUNGG) which survey the star formation properties of HI selected galaxies as traced by H-alpha and ultraviolet emission, respectively. The correlations found demonstrate a strong relationship between the neutral ISM, young massive stars, and the evolved stellar populations. For example the correlation between R band surface brightness and the HI cycling time is tighter than the Kennicutt-Schmidt Star Formation Law. Other scaling relations from SINGG give strong direct confirmation of the downsizing scenario: low mass galaxies are more gaseous and less evolved into stars than high mass galaxies. There are strong variations in the H-alpha to UV flux ratios within and between galaxies. The only plausible explanations for this result are that either the escape fraction of ionizing photons or the upper end of the IMF varies with galaxy mass. We argue for the latter interpretation, although either result has major implications for astrophysics. A detailed dissection of the massive star content in the extended HI disk of NGC2915 provides a consistent picture of continuing star formation with a truncated or steep IMF, while other GALEX results indicate that star formation edges seen in Halpha are not always apparent in the UV. These and other recent results settle some old questions but open many new questions about star formation and its relation to the ISM.
description: To appear in AIP Conference Proceedings, "The Evolution of Galaxies through the Neutral Hydrogen Window", Feb 1-3 2008, Arecibo, Puerto Rico, eds. R. Minchin & E. Momjian. 7 pages