cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Resonance mediated by fermions in kink-antikink collisions
Creators: name: Bazeia, Dionisio
name: Campos, João G. F.
name: Mohammadi, Azadeh
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Pattern Formation and Solitons (nlin.PS)
subject: FOS: Physical sciences

description: We investigate generalizations of the $ϕ^4$ and sine-Gordon models, including interactions with Dirac Fermions. We observe new resonance phenomena by taking the fermion back-reaction into account. First, we show that the vibrational mode responsible for the resonance structure of the $ϕ^4$ model has the same frequency as the energy of the fermion excited state when the back-reaction becomes more significant. Second, we consider the sine-Gordon model with the addition of a fermion field and find that a resonant structure appears, despite the absence of a scalar vibrational mode. The vibrational frequency of the mode responsible for the exchange mechanism is again the energy of the fermion excited state. Therefore, we find a new type of resonant energy exchange mechanism which is mediated by fermions.
description: Accepted for publication in JHEP
A quantitative model of takeover request time budget for conditionally automated driving
Creators: name: Tanshi, Foghor
name: Söffker, Dirk
Publisher: name: arXiv
Year: 2024
Subjects: subject: Systems and Control (eess.SY)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Human-Computer Interaction (cs.HC)
subject: Robotics (cs.RO)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: In conditional automation, the automated driving system assumes full control and only issues a takeover request to a human driver to resume driving in critical situations. Previous studies have concluded that the time budget required by drivers to resume driving after a takeover request varies with situations and different takeover variables. However, no comprehensive generalized approaches for estimating in advance the time budget required by drivers to takeover have been provided. In this contribution, fixed (7 s) and variable time budgets (6 s, 5 s, and 4 s) with and without visual imagery assistance were investigated for suitability in three takeover scenarios using performance measures such as average lateral displacement. The results indicate that 7 s is suitable for two of the studied scenarios based on their characteristics. Using the obtained results and known relations between takeover variables, a mathematical formula for estimating takeover request time budget is proposed. The proposed formula integrates individual stimulus response time, driving experience, scenario specific requirements and allows increased safety for takeover maneuvers. Furthermore, the visual imagery resulted in increased takeover time which invariably increases the time budget. Thus the time demand of the visualized information if applicable (such as visual imagery) should be included in the time budget.
description: Manuscript: 12 pages, 12 figures, 7 tables
Entanglement harvesting: state dependence and covariance
Creators: name: Maeso-García, Héctor
name: Polo-Gómez, José
name: Martín-Martínez, Eduardo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We analyze entanglement harvesting for arbitrary initial states of particle detectors and arbitrary quasifree states of the field. Despite the fact that spatially smeared particle detectors are known to break covariance for arbitrary initial states, we show that the entanglement harvested by a pair of detectors from a quasifree state of a scalar field is a covariant quantity up to second order in perturbation theory.
description: 7 Pages. RevTeX 4.2
The BioExcel methodology for developing dynamic, scalable, reliable and portable computational biomolecular workflows
Creators: name: Ejarque, Jorge
name: Andrio, Pau
name: Hospital, Adam
name: Conejero, Javier
name: Lezzi, Daniele
name: Gelpi, Josep LL.
name: Badia, Rosa M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences
subject: D.1; D.2; J.3

description: Developing complex biomolecular workflows is not always straightforward. It requires tedious developments to enable the interoperability between the different biomolecular simulation and analysis tools. Moreover, the need to execute the pipelines on distributed systems increases the complexity of these developments. To address these issues, we propose a methodology to simplify the implementation of these workflows on HPC infrastructures. It combines a library, the BioExcel Building Blocks (BioBBs), that allows scientists to implement biomolecular pipelines as Python scripts, and the PyCOMPSs programming framework which allows to easily convert Python scripts into task-based parallel workflows executed in distributed computing systems such as HPC clusters, clouds, containerized platforms, etc. Using this methodology, we have implemented a set of computational molecular workflows and we have performed several experiments to validate its portability, scalability, reliability and malleability.
description: Accepted in IEEE eScience conference 2022
Scalable Adversarial Attack Algorithms on Influence Maximization
Creators: name: Sun, Lichao
name: Rui, Xiaobin
name: Chen, Wei
Publisher: name: arXiv
Year: 2022
Subjects: subject: Social and Information Networks (cs.SI)
subject: Data Structures and Algorithms (cs.DS)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: In this paper, we study the adversarial attacks on influence maximization under dynamic influence propagation models in social networks. In particular, given a known seed set S, the problem is to minimize the influence spread from S by deleting a limited number of nodes and edges. This problem reflects many application scenarios, such as blocking virus (e.g. COVID-19) propagation in social networks by quarantine and vaccination, blocking rumor spread by freezing fake accounts, or attacking competitor's influence by incentivizing some users to ignore the information from the competitor. In this paper, under the linear threshold model, we adapt the reverse influence sampling approach and provide efficient algorithms of sampling valid reverse reachable paths to solve the problem. We present three different design choices on reverse sampling, which all guarantee $1/2 - \varepsilon$ approximation (for any small $\varepsilon >0$) and an efficient running time.
description: 11 pages, 2 figures
A Variational Approach to the Quantum Separability Problem
Creators: name: Consiglio, Mirko
name: Apollaro, Tony John George
name: Wieśniak, Marcin
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present the variational separability verifier (VSV), which is a novel variational quantum algorithm (VQA) that determines the closest separable state (CSS) of an arbitrary quantum state with respect to the Hilbert-Schmidt distance (HSD). We first assess the performance of the VSV by investigating the convergence of the optimization procedure for Greenberger-Horne-Zeilinger (GHZ) states of up to seven qubits, using both statevector and shot-based simulations. We also numerically determine the (CSS) of maximally entangled multipartite $X$-states ($X$-MEMS), and subsequently use the results of the algorithm to surmise the analytical form of the aforementioned (CSS). Our results indicate that current noisy intermediate-scale quantum (NISQ) devices may be useful in addressing the $NP$-hard full separability problem using the VSV, due to the shallow quantum circuit imposed by employing the destructive SWAP test to evaluate the (HSD). The (VSV) may also possibly lead to the characterization of multipartite quantum states, once the algorithm is adapted and improved to obtain the closest $k$-separable state ($k$-CSS) of a multipartite entangled state.
description: 13 pages, 7 figures
Higher Order Oscillating Sequences, Affine Distal Flows on the $d$-Torus, and Sarnak's Conjecture
Creators: name: Jiang, Yunping
Publisher: name: arXiv
Year: 2016
Subjects: subject: Dynamical Systems (math.DS)
subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11K65, 37A35 (Primary), 37A25, 11N05 (Secondary)

description: In this paper, we give two precise definitions of a higher order oscillating sequence and show the importance of this concept in the study of Sarnak's conjecture. We prove that any higher order oscillating sequence of order $d$ is linearly disjoint from all affine distal flows on the $d$-torus for all $d\geq 2$. One consequence of this result is that any higher order oscillating sequence of order $2$ is linearly disjoint from all affine flows on the $2$-torus with zero topological entropy. In particular, this reconfirms Sarnak's conjecture for all affine flows on the $2$-torus with zero topological entropy and for all affine distal flows on the $d$-torus for all $d\geq 2$.
Nonlinear symmetries of black hole entropy in gauged supergravity
Creators: name: Klemm, Dietmar
name: Marrani, Alessio
name: Petri, Nicolò
name: Rabbiosi, Marco
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Freudenthal duality in N=2, D=4 ungauged supergravity is generated by an anti-involutive operator that acts on the electromagnetic fluxes, and results to be a symmetry of the Bekenstein-Hawking entropy. We show that, with a suitable extension, this duality can be generalized to the abelian gauged case as well, even in presence of hypermultiplets. By defining Freudenthal duality along the scalar flow, one can prove that two configurations of charges and gaugings linked by the Freudenthal operator share the same set of values of the scalar fields at the black hole horizon. Consequently, Freudenthal duality is promoted to a nonlinear symmetry of the black hole entropy. We explicitly show this invariance for the model with prepotential $F=-i X^0 X^1$ and Fayet-Iliopoulos gauging.
description: 16 pages, uses jheppub.sty
Maxwell theory of fractons
Creators: name: Bertolini, Erica
name: Maggiore, Nicola
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We show that the main properties of the fracton quasiparticles can be derived from a generalized covariant Maxwell-like action. Starting from a rank-2 symmetric tensor field $A_{μν}(x)$, we build a partially symmetric rank-3 tensor field strength $F_{μνρ}(x)$ which obeys a kind of Bianchi identity. The most general action invariant under the covariant ``fracton'' transformation $δ_{fract}A_{μν}(x)=\partial_μ\partial_νΛ(x)$ consists of two independent terms: one describing Linearized Gravity (LG) and the other referable to fractons. The whole action can be written in terms of $F_{μνρ}(x)$, and the fracton part of the invariant Lagrangian writes as $F^2(x)$, in analogy with Maxwell theory. The canonical momentum derived from the fracton Lagrangian coincides with the tensor electric field appearing in the fracton Literature, and the field equations of motion, which have the same form as the covariant Maxwell equations ($\partial^μF_{αβμ}(x)=0$), can be written in terms of the generalized electric and magnetic fields and yield two of the four Maxwell equations (generalized electric Gauss and Ampère laws), while the other two (generalized magnetic Gauss and Faraday laws) are consequences of the ``Bianchi identity'' for the tensor $F_{μνρ}(x)$, as in Maxwell theory. In the covariant generalization of the fracton theory, the equations describing the fracton limited mobility, $i.e.$ the charge and dipole conservation, are not external constraints, but rather consequences of the field equations of motion, hence of the invariant action and, ultimately, of the fracton covariant symmetry. Finally, we increase the known analogies between LG and fracton theory by noting that both satisfy the generalized Gauss constraint which underlies the limited mobility property, which one would not expect in LG.
description: 27 pages, published in Phys.Rev.D
Explicit Cutoff Regularization in Coordinate Representation
Creators: name: Ivanov, A. V.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: In this paper, we study a special type of cutoff regularization in the coordinate representation. We show how this approach unites such concepts and properties as an explicit cut, a spectral representation, a homogenization, and a covariance. Besides that, we present new formulae to work with the regularization and give additional calculations of the infrared asymptotics for some regularized Green's functions, appearing in the pure four-dimensional Yang-Mills theory and in the standard two-dimensional Sigma-model.
description: LaTeX, 17 pages
Quantum master equations for a fast particle in a gas
Creators: name: Gaspard, David
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The propagation of a fast particle in a low-density gas at thermal equilibrium is studied in the context of quantum mechanics. A quantum master equation in the Redfield form governing the reduced density matrix of the particle is derived explicitly from first principles. Under some approximations, this equation reduces to the linear Boltzmann equation. The issue of the positivity of the time evolution is also discussed by means of a Lindblad form. The Born and Markov assumptions underlying these equations, as well as other approximations regarding the bath correlation function, are discussed in details. Furthermore, all these master equations are shown to be equivalent with each other if the density matrix of the particle is diagonal in the momentum basis, or if the collision rate is independent of the particle momentum.
description: 18 pages, 81 references
Code for manuscript entitled "Exponential or unimodal relationships between nighttime ecosystem respiration and temperature at the eddy covariance flux tower sites".
Creators: name: Meng, Cheng
name: Xiao, Xiangming
name: Wagle, Pradeep
name: Zhang, Chenchen
name: Pan, Li
name: Pan, Baihong
name: Qin, Yuanwei
name: Newman, Gregory
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 310308
subject: Terrestrial ecology

description: Code for manuscript entitled "Exponential or unimodal relationships between nighttime ecosystem respiration and temperature at the eddy covariance flux tower sites" for consideration in Ecology Letters.
Dissipative Quantum Vortices and Superradiant Scattering
Creators: name: Cardoso, Thiago A. S.
name: Richartz, Maurício
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Inspired by Analogue Gravity, superradiance has been previously investigated in Bose-Einstein condensates (BECs). In this work, we revisit this problem by introducing dissipation to the system. After establishing the possibility of quantum vortices in dissipative BECs, we analyze the propagation of elementary excitations and demonstrate the existence of superradiant modes which can be interpreted in terms of the dissipation of ``antiparticles". Our findings support the possibility of superradiant scattering around dissipative quantum vortices and paves the way for future experimental realization of the phenomenon.
description: v2: 12 pages, 4 figures, matches published version
Very long-periodic pulsations detected simultaneously in a white-light flare and sunspot penumbra
Creators: name: Li, Dong
name: Wang, Jincheng
name: Huang, Yu
Publisher: name: arXiv
Year: 2024
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We investigate the origin of very long-periodic pulsations (VLPs) in the white-light emission of an X6.4 flare on 2024 February 22 (SOL2024-02-22T22:08), which occurred at the edge of a sunspot group. The flare white-light fluxes reveal four successive and repetitive pulsations, which are simultaneously measured by the Helioseismic and Magnetic Imager and the White-light Solar Telescope. A quasi-period of 8.6$^{+1.5}_{-1.9}$ minutes, determined by the Morlet wavelet transform, is detected in the visible continuum channel. The modulation depth, which is defined as the ratio between the oscillatory amplitude and its long-term trend, is smaller than 0.1%, implying that the QPP feature is a weak wave process. Imaging observations show that the X6.4 flare occurs near a sunspot group. Moreover, the white-light brightening is located in sunspot penumbra, and a similar quasi-period of about 8.5$^{+1.6}_{-1.8}$ minutes is identified in one penumbral location of the nearest sunspot. The map of Fourier power distribution suggests that a similar periodicity is universally existing in most parts of the penumbra that is close to the penumbral-photospheric boundary. Our observations support the scenario of that the white-light QPP is probably modulated by the slow-mode magnetoacoustic gravity wave leaking from the sunspot penumbra.
description: published in ApJL
The Poor Old Heart of the Milky Way
Creators: name: Rix, Hans-Walter
name: Chandra, Vedant
name: Andrae, René
name: Price-Whelan, Adrian M.
name: Weinberg, David H.
name: Conroy, Charlie
name: Fouesneau, Morgan
name: Hogg, David W.
name: De Angeli, Francesca
name: Naidu, Rohan P.
name: Xiang, Maosheng
name: Ruz-Mieres, Daniela
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Massive disk galaxies like our Milky Way should host an ancient, metal-poor, and centrally concentrated stellar population. This population reflects the star formation and enrichment in the few most massive progenitor components that coalesced at high redshift to form the proto-Galaxy. While metal-poor stars are known to reside in the inner few kiloparsecs of our Galaxy, current data do not yet provide a comprehensive picture of such a metal-poor "heart" of the Milky Way. We use information from Gaia DR3, especially the XP spectra, to construct a sample of 2 million bright (BP $<15.5$ mag) giant stars within $30^\circ$ of the Galactic Center with robust [M/H] estimates, $δ$ [M/H] $\lesssim 0.1$. For most sample members we can calculate orbits based on Gaia RVS velocities and astrometry. This sample reveals an extensive, ancient, and metal-poor population that includes $\sim 18,000$ stars with $-2.7<$ [M/H] $<-1.5$, representing a stellar mass of $\gtrsim 5\times 10^7$ M$_\odot$. The spatial distribution of these [M/H] $<-1.5$ stars has a Gaussian extent of only $σ_{\mathrm{R_{GC}}} \sim 2.7$ kpc around the Galactic center, with most of these orbits being confined to the inner Galaxy. At high orbital eccentricities, there is clear evidence for accreted halo stars in their pericentral orbit phase. Stars with [M/H] $< -2$ show no net rotation, whereas those with [M/H] $\sim -1$ are rotation dominated. Most of the tightly bound stars show $[α/\text{Fe}]$-enhancement and [Al/Fe]-[Mn/Fe] abundance patterns expected for an origin in the more massive portions of the proto-Galaxy. These central, metal-poor stars most likely predate the oldest part of the disk ($τ_{\text{age}}\approx 12.5$ Gyrs), which implies that they formed at $z\gtrsim 5$, forging the proto-Milky Way.
description: 21 pages, 9 figures, submitted to ApJ
More Circulant Graphs exhibiting Pretty Good State Transfer
Creators: name: Pal, Hiranmoy
Publisher: name: arXiv
Year: 2017
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C12, 05C50

description: The transition matrix of a graph $G$ corresponding to the adjacency matrix $A$ is defined by $H(t):=\exp{\left(-itA\right)},$ where $t\in\mathbb{R}$. The graph is said to exhibit pretty good state transfer between a pair of vertices $u$ and $v$ if there exists a sequence $\left\lbrace t_k\right\rbrace$ of real numbers such that $\lim\limits_{k\rightarrow\infty} H(t_k) {\bf e}_u=γ{\bf e}_v$, where $γ$ is a complex number of unit modulus. We classify some circulant graphs exhibiting or not exhibiting pretty good state transfer. This generalize several pre-existing results on circulant graphs admitting pretty good state transfer.
A Volcanic Hydrogen Habitable Zone
Creators: name: Ramirez, Ramses
name: Kaltenegger, Lisa
Publisher: name: arXiv
Year: 2017
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The classical habitable zone is the circular region around a star in which liquid water could exist on the surface of a rocky planet. The outer edge of the traditional N2-CO2-H2O habitable zone (HZ) extends out to nearly 1.7 AU in our Solar System, beyond which condensation and scattering by CO2 outstrips its greenhouse capacity. Here, we show that volcanic outgassing of atmospheric H2 on a planet near the outer edge can extend the habitable zone out to ~2.4 AU in our solar system. This wider volcanic hydrogen habitable zone (N2-CO2-H2O-H2) can be sustained as long as volcanic H2 output offsets its escape from the top of the atmosphere. We use a single-column radiative-convective climate model to compute the HZ limits of this volcanic hydrogen habitable zone for hydrogen concentrations between 1% and 50%, assuming diffusion-limited atmospheric escape. At a hydrogen concentration of 50%, the effective stellar flux required to support the outer edge decreases by ~35% to 60% for M to A stars. The corresponding orbital distances increase by ~30% to 60%. The inner edge of this HZ only moves out by ~0.1 to 4% relative to the classical HZ because H2 warming is reduced in dense H2O atmospheres. The atmospheric scale heights of such volcanic H2 atmospheres near the outer edge of the HZ also increase, facilitating remote detection of atmospheric signatures.
description: 13 pages, 3 figures, 2 tables (published in The Astrophysical Journal Letters)
Joseph Wolfgang von Deschwanden (1819-1866) an Ottilie Grossbach (1836-1919), verheiratete von Deschwanden
Creators: name: Deschwanden, Joseph Wolfgang von
Publisher: name: [s.n.]
Year: 1862

description: Brief aus Weggis, adressiert an Ottilie von Deschwanden, Rigi-Kaltbad, datiert mit Sonntag 24.8.
Atmospheric retrievals suggest the presence of a secondary atmosphere and possible sulfur species on L 98-59 d from JWST NIRSpec G395H transmission spectroscopy
Creators: name: Banerjee, Agnibha
name: Barstow, Joanna K.
name: Gressier, Amélie
name: Espinoza, Néstor
name: Sing, David K.
name: Allen, Natalie H.
name: Birkmann, Stephan M.
name: Challener, Ryan C.
name: Crouzet, Nicolas
name: Haswell, Carole A.
name: Lewis, Nikole K.
name: Lewis, Stephen R.
name: Yang, Jingxuan
Publisher: name: arXiv
Year: 2024
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: L 98-59 d is a Super-Earth planet orbiting an M-type star. We performed retrievals on the transmission spectrum of L 98-59 d obtained using NIRSpec G395H during a single transit, from JWST Cycle 1 GTO 1224. The wavelength range of this spectrum allows us to detect the presence of several atmospheric species. We found that the spectrum is consistent with a high mean molecular weight atmosphere. The atmospheric spectrum indicates the possible presence of the sulfur-bearing species H$_2$S and SO$_2$, which could hint at active volcanism on this planet if verified by future observations. We also tested for signs of stellar contamination in the spectrum, and found signs of unocculted faculae on the star. The tentative signs of an atmosphere on L 98-59 d presented in this work from just one transit bodes well for possible molecular detections in the future, particularly as it is one of the best targets among small exoplanets for atmospheric characterization using JWST.
description: Accepted for publication to ApJL
Superconducting diode effect and nonreciprocal transition lines
Creators: name: Daido, Akito
name: Yanase, Youichi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Nonreciprocity in superconductors is attracting much interest owing to its fundamental importance as well as its potential applicability to engineering. In this paper, we generalize the previous theories of the intrinsic superconducting diode effect (SDE) and microscopically elucidate its relationship with the nonreciprocity of the transition lines under supercurrent. We derive a general formula for the intrinsic SDE by using the phenomenological Ginzburg-Landau theory and thereby show that the SDE is determined by the relative angle between the magnetic field and an effective anti-symmetric spin-orbit coupling defined from the Ginzburg-Landau coefficients. The obtained formula offers a convenient criterion to obtain a finite SDE. We also study the SDE and the nonreciprocal phase transitions of the $s$-wave and $d$-wave superconductors by using the mean-field theory. It is established that the sign reversal of the SDE accompanied by the crossover of the helical superconductivity is a general feature irrespective of the system details. We study the phase transition lines in the temperature-magnetic-field phase diagram under the supercurrent, and clarify that the sign reversal of the SDE generally accompanies the crossings of the transition lines under positive and negative current directions. Furthermore, the superconducting phases under the supercurrent even become re-entrant under moderate strength of the electric current, implying the current-induced first-order phase transitions. Our findings establish the electric current as the control parameter and the powerful probe to study the superconducting properties related to the finite-momentum Cooper pairs.
description: 20 pages, 14 figures
Symbolic Representation and Classification of Logos
Creators: name: Guru, D. S.
name: Kumar, N. Vinay
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences
subject: I.4.9; I.4.9; I.5.0; I.5.4
subject: 68U10

description: In this paper, a model for classification of logos based on symbolic representation of features is presented. The proposed model makes use of global features of logo images such as color, texture, and shape features for classification. The logo images are broadly classified into three different classes, viz., logo image containing only text, an image with only symbol, and an image with both text and a symbol. In each class, the similar looking logo images are clustered using K-means clustering algorithm. The intra-cluster variations present in each cluster corresponding to each class are then preserved using symbolic interval data. Thus referenced logo images are represented in the form of interval data. A sample logo image is then classified using suitable symbolic classifier. For experimentation purpose, relatively large amount of color logo images is created consisting of 5044 logo images. The classification results are validated with the help of accuracy, precision, recall, F-measure, and time. To check the efficacy of the proposed model, the comparative analyses are given against the other models. The results show that the proposed model outperforms the other models with respect to time and F-measure.
description: 15 pages, 6 figures, 6 tables, Proceedings of International Conference on Computer Vision and Image Processing (CVIP 2016). arXiv admin note: text overlap with arXiv:1609.01414
Perspective: non-Hermitian physics in magnetic systems
Creators: name: Hurst, Hilary M.
name: Flebus, Benedetta
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Non-Hermitian Hamiltonians provide an alternative perspective on the dynamics of quantum and classical systems coupled non-conservatively to an environment. Once primarily an interest of mathematical physicists, the theory of non-Hermitian Hamiltonians has solidified and expanded to describe various physically observable phenomena in optical, photonic, and condensed matter systems. Self-consistent descriptions of quantum mechanics based on non-Hermitian Hamiltonians have been developed and continue to be refined. In particular, non-Hermitian frameworks to describe magnonic and hybrid magnonic systems have gained popularity and utility in recent years, with new insights into the magnon topology, transport properties, and phase transitions coming into view. Magnonic systems are in many ways a natural platform in which to realize non-Hermitian physics because they are always coupled to a surrounding environment and exhibit lossy dynamics. In this perspective we review recent progress in non-Hermitian frameworks to describe magnonic and hybrid magnonic systems, such as cavity magnonic systems and magnon-qubit coupling schemes. We discuss progress in understanding the dynamics of inherently lossy magnetic systems as well as systems with gain induced by externally applied spin currents. We enumerate phenomena observed in both purely magnonic and hybrid magnonic systems which can be understood through the lens of non-Hermitian physics, such as PT and Anti-PT-symmetry breaking, dynamical magnetic phase transitions, non-Hermitian skin effect, and the realization of exceptional points and surfaces. Finally, we comment on some open problems in the field and discuss areas for further exploration.
description: 15 pages, 4 figures, invited Perspective article submitted to Journal of Applied Physics. Updated references and minor copyediting
Steady helix states in a resonant XXZ Heisenberg model with Dzyaloshinskii-Moriya interaction
Creators: name: Ma, E. S.
name: Zhang, K. L.
name: Song, Z.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We systematically investigate possible helix states in XXZ Heisenberg model with Dzyaloshinskii-Moriya (DM) interaction. Exact solutions show that a set of precession helix states can be constructed by deliberate superposition of degenerate eigenstates of the Hamiltonian under the resonant condition. When a non-Hermitian balance boundary term is imposed as a quenching action, the quench dynamics shows that a steady helix state emerges from some easily prepared initial states, including saturate and maximally mixed ferromagnetic states, according to the analysis of perturbation method. The corresponding dynamics for near resonant cases is also investigated numerically, indicating the robustness of the scheme. Our findings highlight the cooperation of non-Hermiticity and the DM interaction in quantum spin system, suggesting a way for preparing steady helix state in non-Hermitian quantum spin system.
description: 9 pages, 4 figures
Stable Homotopy Groups of Moore Spaces
Creators: name: Saihi, Inès
Publisher: name: arXiv
Year: 2024
Subjects: subject: Algebraic Topology (math.AT)
subject: FOS: Mathematics
subject: 55Q10 (Primary) 55U20, 18G99 (Secondary)

description: We determine explicitly the stable homotopy groups of Moore spaces up to the range 7, using an equivalence of categories which allows to consider each Moore space as an exact couple of $\mathbb Z$-modules.
Theoretic Guide for Using Photonic Glasses as Colored Covers for Solar Energy Harvesting
Creators: name: Li, Zhenpeng
name: Li, Sinan
name: Ma, Tao
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: The increasing demand for renewable energy is promoting technologies that integrate solar energy harvesting materials with the human living environment, such as building-integrated photovoltaics (BIPVs). This places requirements on developing colored covers with a trade-off between efficiency and aesthetics, providing a new stage for the large-scale application of structural color technologies. Here in this study, we have investigated the theoretic feasibility of employing the photonic glass, a random packing of monodisperse dielectric microspheres, as the colored cover for solar energy harvesting. Based on numerous optical simulations, we have evaluated the color and average solar transmissivity (AST) of the photonic glasses with varying parameters. Results show that using non-absorbing microspheres with relatively high refractive index, about 3 μm thick photonic glasses could enable colors with lightness over 50 while keeping AST at around 80%. Besides, we demonstrate that due to the short-range structural correlation, photonic glasses could generate purple, blue, cyan, light green, and grey colors, but cannot help with yellow and red color hues. Finally, the effects of several enhancement methods are clarified, and possible ways for expanding the color range are demonstrated. These results provide a comprehensive guide to the practical implementations of structural color using photonic glasses, particularly in the colorization of solar energy materials.
description: 18 Pages, 7 figures, supporting information
Joseph Wolfgang von Deschwanden (1819-1866) an Ottilie Grossbach (1836-1919), verheiratete von Deschwanden
Creators: name: Deschwanden, Joseph Wolfgang von
Publisher: name: [s.n.]
Year: 1862

description: Brief aus Weggis, Gasthof Löwen.
Eine Skizze zeigt den Gasthofl und das Zimmerfenster
An efficient approach to suppress the negative role of contrarian oscillators in synchronization
Creators: name: Zhang, Xiyun
name: Ruan, Zhongyuan
name: Liu, Zonghua
Publisher: name: arXiv
Year: 2017
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: FOS: Physical sciences

description: It has been found that contrarian oscillators usually take a negative role in the collective behaviors formed by conformist oscillators. However, experiments revealed that it is also possible to achieve a strong coherence even when there are contrarians in the system such as neuron networks with both excitable and inhibitory neurons. To understand the underlying mechanism of this abnormal phenomenon, we here consider a complex network of coupled Kuramoto oscillators with mixed positive and negative couplings and present an efficient approach, i.e. tit-for-tat strategy, to suppress the negative role of contrarian oscillators in synchronization and thus increase the order parameter of synchronization. Two classes of contrarian oscillators are numerically studied and a brief theoretical analysis is provided to explain the numerical results.
Determination of diffusion coefficients of mercury atoms in various gases from longitudinal spin relaxation in magnetic gradients
Creators: name: Clément, B.
name: Guigue, M.
name: Leredde, A.
name: Pignol, G.
name: Rebreyend, D.
name: Roccia, S.
name: Touati, S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We present a method to measure the binary diffusion coefficient of mercury atoms in a gas at room temperature and low pressure. It is based on the measurement of the longitudinal spin relaxation of optically pumped mercury-199 atoms in a magnetic field gradient. We provide a consistent set of diffusion coefficients for helium-3, helium-4, argon, krypton, xenon, nitrogen, carbon dioxide, oxygen, and air.
3 Recommendations for Machine Unlearning Evaluation Challenges
Creators: name: Grimes, Keltin
name: Abidi, Collin
name: Frank, Cole
Publisher: name: Carnegie Mellon University
Year: 2024
Subjects: Software Engineering

description: Machine learning (ML) models are becoming more deeply integrated into many products and services we use every day. This proliferation of artificial intelligence (AI)/ML technology raises a host of concerns about privacy breaches, model bias, and unauthorized use of data to train models. All of these areas point to the importance of having flexible and responsive control over the data a model is trained on. Retraining a model from scratch to remove specific data points, however, is often impractical due to the high computational and financial costs involved. Research into machine unlearning (MU) aims to develop new methods to remove data points efficiently and effectively from a model without the need for extensive retraining. In this post from the Carnegie Mellon University Software Engineering Institute, we discuss our work on machine unlearning challenges and offer recommendations for more robust evaluation methods.
title: 3 Recommendations for Machine Unlearning Evaluation Challenges
Creators: name: Grimes, Keltin
name: Abidi, Collin
name: Frank, Cole
Publisher: name: Software Engineering Institute
publisherIdentifier: https://ror.org/01xqjjn94
publisherIdentifierScheme: ROR
Year: 2024

description: Machine learning (ML) models are becoming more deeply integrated into many products and services we use every day. This proliferation of artificial intelligence (AI)/ML technology raises a host of concerns about privacy breaches, model bias, and unauthorized use of data to train models. All of these areas point to the importance of having flexible and responsive control over the data a model is trained on. Retraining a model from scratch to remove specific data points, however, is often impractical due to the high computational and financial costs involved. Research into machine unlearning (MU) aims to develop new methods to remove data points efficiently and effectively from a model without the need for extensive retraining. In this post from the Carnegie Mellon University Software Engineering Institute, we discuss our work on machine unlearning challenges and offer recommendations for more robust evaluation methods.
De Sitter bubbles from anti-de Sitter fluctuations
Creators: name: Biasi, Anxo
name: Evnin, Oleg
name: Sypsas, Spyros
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Cosmological acceleration is difficult to accommodate in theories of fundamental interactions involving supergravity and superstrings. An alternative is that the acceleration is not universal but happens in a large localized region, which is possible in theories admitting regular black holes with de Sitter-like interiors. We considerably strengthen this scenario by placing it in a global anti-de Sitter background, where the formation of 'de Sitter bubbles' will be enhanced by mechanisms analogous to the Bizon-Rostworowski instability in general relativity. This opens an arena for discussing the production of multiple accelerating universes from anti-de Sitter fluctuations. We demonstrate such collapse enhancement by explicit numerical work in the context of a simple two-dimensional dilaton-gravity model that mimics the spherically symmetric sector of higher-dimensional gravities.
description: v3: minor improvements, accepted for publication in Phys.Rev.Lett
Theory of adiabatic fountain resonance
Creators: name: Williams, Gary A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: The theory of "Adiabatic Fountain Resonance" with superfluid $^4$He is clarified. In this geometry a film region between two silicon wafers bonded at their outer edge opens up to a central region with a free surface. We find that the resonance in this system is not a Helmholtz resonance as claimed by Gasparini and co-workers, but in fact is a fourth sound resonance. We postulate that it occurs at relatively low frequency because the thin silicon wafers flex appreciably from the pressure oscillations of the sound wave.
description: Accepted for Journal of Low Temperature Physics
An analytical study of the MHD clamshell instability on a sphere
Creators: name: Wang, Chen
name: Gilbert, Andrew D.
name: Mason, Joanne
Publisher: name: arXiv
Year: 2022
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: This paper studies the instability of two-dimensional magnetohydrodynamic (MHD) systems on a sphere using analytical methods. The underlying flow consists of a zonal differential rotation and a toroidal magnetic field is present. Semicircle rules that prescribe the possible domain of the wave velocity in the complex plane for general flow and field profiles are derived. The paper then sets out an analytical study of the `clamshell instability', which features field lines on the two hemispheres tilting in opposite directions (Cally 2001, Sol. Phys. vol. 199, pp. 231--249). An asymptotic solution for the instability problem is derived for the limit of weak shear of the zonal flow, via the method of matched asymptotic expansions. It is shown that when the zonal flow is solid body rotation, there exists a neutral mode that tilts the magnetic field lines, referred to as the `tilting mode'. A weak shear of the zonal flow excites the critical layer of the tilting mode, which reverses the tilting direction to form the clamshell pattern and induces the instability. The asymptotic solution provides insights into properties of the instability for a range of flow and field profiles. A remarkable feature is that the magnetic field affects the instability only through its local behaviour in the critical layer.
A systematic search for hidden type 1 AGNs: gas kinematics and scaling relations
Creators: name: Eun, Da-In
name: Woo, Jong-Hak
name: Bae, Hyun-Jin
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We search type 1 AGNs among emission-line galaxies, that are typically classified as type 2 AGNs based on emission line flux ratios if a broad component in the H$α$ line profile is not properly investigated. Using ~24,000 type 2 AGNs at z $
description: ApJ submitted, revised based on referee's comments, 12 pages, 12 figures
Running of the Charm-Quark Mass from HERA Deep-Inelastic Scattering Data
Creators: name: Gizhko, A.
name: Geiser, A.
name: Moch, S.
name: Abt, I.
name: Behnke, O.
name: Bertolin, A.
name: Blümlein, J.
name: Britzger, D.
name: Brugnera, R.
name: Buniatyan, A.
name: Bussey, P. J.
name: Carlin, R.
name: Cooper-Sarkar, A. M.
name: Daum, K.
name: Dusini, S.
name: Elsen, E.
name: Favart, L.
name: Feltesse, J.
name: Foster, B.
name: Garfagnini, A.
name: Garzelli, M.
name: Gayler, J.
name: Haidt, D.
name: Hladky, J.
name: Jung, A. W.
name: Kapichine, M.
name: Korzhavina, I. A.
name: Levchenko, B. B.
name: Lipka, K.
name: Lisovyi, M.
name: Longhin, A.
name: Mikocki, S.
name: Naumann, Th.
name: Nowak, G.
name: Paul, E.
name: Plačakytė, R.
name: Rabbertz, K.
name: Schmitt, S.
name: Shcheglova, L. M.
name: Si, Z.
name: Spiesberger, H.
name: Stanco, L.
name: Truöl, P.
name: Tymieniecka, T.
name: Verbytskyi, A.
name: Wichmann, K.
name: Wing, M.
name: Żarnecki, A. F.
name: Zenaiev, O.
name: Zhang, Z.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Combined HERA data on charm production in deep-inelastic scattering have previously been used to determine the charm-quark running mass $m_c(m_c)$ in the MSbar renormalisation scheme. Here, the same data are used as a function of the photon virtuality $Q^2$ to evaluate the charm-quark running mass at different scales to one-loop order, in the context of a next-to-leading order QCD analysis. The scale dependence of the mass is found to be consistent with QCD expectations.
description: 12 pages, 4 figures
Large Bilinear Magnetoresistance from Rashba Spin-Splitting on the Surface of a Topological Insulator
Creators: name: Wang, Yang
name: Liu, Binbin
name: Huang, Yue-Xin
name: Mambakkam, Sivakumar V.
name: Wang, Yong
name: Yang, Shengyuan A.
name: Sheng, Xian-Lei
name: Law, Stephanie A.
name: Xiao, John Q.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: In addition to the topologically protected linear dispersion, a band-bending-confined two-dimensional electron gas with tunable Rashba spin-splitting (RSS) was found to coexist with the topological surface states on the surface of topological insulators (TIs). Here, we report the observation of large bilinear magnetoresistance (BMR) in Bi2Se3 films decorated with transition metal atoms. The magnitude of the BMR sensitively depends on the type and amount of atoms deposited, with a maximum achieved value close to those of strong Rashba semiconductors. Our first-principles calculations reproduce the quantum well states and reveal sizable RSS in all Bi2Se3 heterostructures with broken inversion symmetry. Our results show that charge-spin interconversion through RSS states in TIs can be fine-tuned through surface atom deposition and easily detected via BMR for potential spintronic applications.
description: Typos in Fig. 4 caption and Ref. [27] were corrected in this version
Efficient reconstruction of CASCI-type wave functions for a DMRG state using quantum information theory and genetic algorithm
Creators: name: Luo, Zhen
name: Ma, Yingjin
name: Liu, Chungen
name: Ma, Haibo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We improve the methodology to construct a complete active space-configuration interaction (CAS-CI) expansion for density-matrix renormalization group (DMRG) wave function using matrix-product state representation, inspired by the sampling-reconstructed CAS [SR-CAS, Boguslawski et al, J. Chem. Phys. 2011, 134, 224101] algorithm. In our scheme, a genetic algorithm, in which the "crossover" and "mutation" process can be optimized based on quantum information theory, is employed when reconstructing the CASCI-type wave function in the Hilbert space. Test analysis results for the ground and excited state wave functions of conjugated molecules and transition metal compounds illustrate that our scheme is very efficient for searching the most important CI expansions in large active spaces.
description: 27 pages, 9 figures
Bifurcations, stability, and mode evolution in segregated condensate mixtures
Creators: name: Pal, Sukla
name: Roy, Arko
name: Angom, D.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We present new features of low energy Bogoliubov quasiparticle excitations of a two component Bose-Einstein condensate (TBEC) in quasi-2D geometry at zero temperature using Hartree-Fock-Bogoliubov (HFB). We, in particular, consider the TBECs of $^{133}$Cs~-$^{87}$Rb and $^{85}$Rb~-$^{87}$Rb, and show specific features in the low energy excitation spectrum as a function of the interaction strength. For $^{85}$Rb~-$^{87}$Rb TBEC, the appearance of a new zero energy mode is observed. Whereas for $^{133}$Cs~-$^{87}$Rb TBEC we report a bifurcation of the softened Kohn mode at the point of transition from miscible to immiscible domain. The lower energy mode, after the bifurcation, goes soft and becomes a new Goldstone mode of the system.
description: The paper has 9 pages and 12 figures