cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Spherically symmetric, static black holes with scalar hair, and naked singularities in nonminimally coupled k-essence
Creators: name: Nagy, Cecília
name: Keresztes, Zoltán
name: Gergely, László Á.
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: We apply a recently developed 2+1+1 decomposition of spacetime, based on a nonorthogonal double foliation for the study of spherically symmetric, static black hole solutions of Horndeski scalar-tensor theory. Our discussion proceeds in an effective field theory (EFT) of modified gravity approach, with the action depending on metric and embedding scalars adapted to the nonorthogonal 2+1+1 decomposition. We prove that the most generic class of Horndeski Lagrangians compatible with observations can be expressed in this EFT form. By studying the first order perturbation of the EFT action we derive three equations of motion, which reduce to those derived earlier in an orthogonal 2+1+1 decomposition, and a fourth equation for the metric parameter N related to the nonorthogonality of the foliation. For the Horndeski class of theories with vanishing $G_3$ and $G_5$, but generic functions $G_2(ϕ,X)$ (k-essence) and $G_4(ϕ)$ (nonminimal coupling to the metric) we prove the unicity theorem that no action beyond Einstein--Hilbert allows for the Schwarzschild solution. Next we integrate the EFT field equations for the case with only one independent metric function obtaining new solutions characterized by a parameter interpreted as either mass or tidal charge, the cosmological constant and a third parameter. These solutions represent naked singularities, black holes with scalar hair or have the double horizon structure of the Schwarzschild--de Sitter spacetime. Solutions with homogeneous Kantowski--Sachs type regions also emerge. Finally, one of the solutions obtained for the function $G_4$ linear in the curvature coordinate, in certain parameter range exhibits an intriguing logarithmic singularity lying outside the horizon. The newly derived hairy black hole solutions evade previously known unicity theorems by being asymptotically nonflat, even in the absence of the cosmological constant.
description: 20 pages, 4 figures
A Systematic Comparison of Galaxy Cluster Temperatures Measured with NuSTAR and Chandra
Creators: name: Wallbank, A. N.
name: Maughan, B. J.
name: Gastaldello, F.
name: Potter, C.
name: Wik, D. R.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Temperature measurements of galaxy clusters are used to determine their masses, which in turn are used to determine cosmological parameters. However, systematic differences between the temperatures measured by different telescopes imply a significant source of systematic uncertainty on such mass estimates. We perform the first systematic comparison between cluster temperatures measured with Chandra and NuSTAR. This provides a useful contribution to the effort of cross-calibrating cluster temperatures due to the harder response of NuSTAR compared with most other observatories. We measure average temperatures for 8 clusters observed with NuSTAR and Chandra. We fit the NuSTAR spectra in a hard (3-10 keV) energy band, and the Chandra spectra in both the hard and a broad (0.6-9 keV) band. We fit a power-law cross-calibration model to the resulting temperatures. At a Chandra temperature of 10 keV, the average NuSTAR temperature was $(10.5 \pm 3.7)\%$ and $(15.7 \pm 4.6)\%$ lower than Chandra for the broad and hard band fits respectively. We explored the impact of systematics from background modelling and multiphase temperature structure of the clusters, and found that these did not affect our results. Our sample are primarily merging clusters with complex thermal structures so are not ideal calibration targets. However, given the harder response of NuSTAR it would be expected to measure a higher average temperature than Chandra for a non-isothermal cluster, so we interpret our measurement as a lower limit on the difference in temperatures between NuSTAR and Chandra.
description: 12 pages plus appendices. Accepted for publication in MNRAS
Quantum Supergroup $U_{r,s}(osp(1,2))$, Scasimir Operators, and Dickson polynomials
Creators: name: Liu, Fu
name: Hu, Naihong
name: Jing, Naihuan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Algebra (math.QA)
subject: FOS: Mathematics
subject: 17B37, 20G42, 33C47

description: We study the center of the two-parameter quantum supergroup $U_{r,s}(osp(1,2))$ using the Dickson polynomial. We show that the Scasimir operator is completely determined by the $q$-deformed Chebychev polynomial, generalizing an earlier work of Arnaudon and Bauer.
Measuring bar pattern speeds from single simulation snapshots
Creators: name: Dehnen, Walter
name: Semczuk, Marcin
name: Schoenrich, Ralph
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We describe methods to measure simultaneously the orientation angle $ψ$ and pattern speed $Ω$ from single snapshots of simulated barred galaxies. Unlike previous attempts, our approach is unbiased, precise, and consistent in the sense that $ψ=\intΩ\mathrm{d}t$. It can be extended to obtain the rate and axis of rotation, i.e. the vector $\boldsymbolΩ$. We provide computer code implementing our method.
description: 7 pages, accepted at MNRAS; v2: clarified discussion of previous work
Calling Bull Case Study — 99.9% Caffeine-free with R
Creators: name: Eaton, Carrie
name: Bergstrom, Carl
name: West, Jevin
Publisher: name: QUBES Educational Resources
Year: 2020

description: This is an adaptation of Calling Bull's Case Study on how caffeine free is hot chocolate versus coffee in order to make it into a student project that uses R.
The Spitzer Survey of Stellar Structure in Galaxies (S$^4$G): Precise Stellar Mass Distributions from Automated Dust Correction at 3.6 microns
Creators: name: Querejeta, M.
name: Meidt, S. E.
name: Schinnerer, E.
name: Cisternas, M.
name: Muñoz-Mateos, J. C.
name: Sheth, K.
name: Knapen, J.
name: van de Ven, G.
name: Norris, M. A.
name: Peletier, R.
name: Laurikainen, E.
name: Salo, H.
name: Holwerda, B. W.
name: Athanassoula, E.
name: Bosma, A.
name: Groves, B.
name: Ho, L. C.
name: Gadotti, D. A.
name: Zaritsky, D.
name: Regan, M.
name: Hinz, J.
name: de Paz, A. Gil
name: Menendez-Delmestre, K.
name: Seibert, M.
name: Mizusawa, T.
name: Kim, T.
name: Erroz-Ferrer, S.
name: Laine, J.
name: Comerón, S.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The mid-infrared is an optimal window to trace stellar mass in nearby galaxies and the 3.6$μm$ IRAC band has been exploited to this effect, but such mass estimates can be biased by dust emission. We present our pipeline to reveal the old stellar flux at 3.6$μm$ and obtain stellar mass maps for more than 1600 galaxies available from the Spitzer Survey of Stellar Structure in Galaxies (S$^{4}$G). This survey consists of images in two infrared bands (3.6 and 4.5$μm$), and we use the Independent Component Analysis (ICA) method presented in Meidt et al. (2012) to separate the dominant light from old stars and the dust emission that can significantly contribute to the observed 3.6$μm$ flux. We exclude from our ICA analysis galaxies with low signal-to-noise ratio (S/N < 10) and those with original [3.6]-[4.5] colors compatible with an old stellar population, indicative of little dust emission (mostly early Hubble types, which can directly provide good mass maps). For the remaining 1251 galaxies to which ICA was successfully applied, we find that as much as 10-30% of the total light at 3.6$μm$ typically originates from dust, and locally it can reach even higher values. This contamination fraction shows a correlation with specific star formation rates, confirming that the dust emission that we detect is related to star formation. Additionally, we have used our large sample of mass estimates to calibrate a relationship of effective mass-to-light ratio ($M/L$) as a function of observed [3.6]-[4.5] color: $\log(M/L)=-0.339 (\pm 0.057) \times ([3.6]-[4.5]) -0.336 (\pm 0.002)$. Our final pipeline products have been made public through IRSA, providing the astronomical community with an unprecedentedly large set of stellar mass maps ready to use for scientific applications.
description: Published by the Astrophysical Journal (Supplements). Data available as a tar-ball from IRSA (http://irsa.ipac.caltech.edu/data/SPITZER/S4G/S4Gp5.tar.gz); searchable option as part of S4G will become available in November 2014. Readme file and table of parameters inside tar-ball (P5_README.txt, P5_table.txt). 2015ApJS..219....5Q
Evaluation of Aerodynamic Characteristics in Oscillatory Coning Using CFD Methods
Creators: name: Sereez, Mohamed
name: Goman, Mikhail
Publisher: name: arXiv
Year: 2022
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: The wind tunnel rotary-balance testing is widely used in aircraft dynamics to characterise aerodynamics at moderate and high angles of attack during stall and spin regimes. In such experiments an aircraft test model is rotated along the wind-tunnel free-stream velocity vector allowing the measurement of aerodynamic characteristics in steady rotational flow conditions with constant angle of attack and sideslip. In modified tests named as oscillatory coning, the rotation vector is tilted from the free-stream velocity vector making flow conditions with periodic variations in angle of attack and sideslip. This allows evaluation of unsteady aerodynamic responses superimposed on steady conical rotation. The use of CFD methods for prediction of aerodynamic characteristics in rotary-balance and oscillatory coning conditions may significantly complement experimental data via extrapolation of data for higher Reynolds numbers, elimination of interference effects from supporting system, extraction of unsteady aerodynamic derivatives affecting aircraft dynamic stability. This paper presents CFD simulation results obtained in rotary-balance and oscillatory coning motions for the NASA Common Research Model (CRM) in its wing-body configuration at moderate $Re=1\times10^6$, low Mach number $M\mbox{=}0.2$ and the use of the obtained unsteady responses in aerodynamic modelling.
Constraints on Electron Acceleration in Gamma-Ray Bursts Afterglows from Radio Peaks
Creators: name: Duncan, Ruby A.
name: van der Horst, Alexander J.
name: Beniamini, Paz
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Studies of gamma-ray bursts (GRBs) and their multi-wavelength afterglows have led to insights in electron acceleration and emission properties from relativistic, high-energy astrophysical sources. Broadband modeling across the electromagnetic spectrum has been the primary means of investigating the physics behind these sources, although independent diagnostic tools have been developed to inform and corroborate assumptions made in particle acceleration simulations and broadband studies. We present a methodology to constrain three physical parameters related to electron acceleration in GRB blast waves: the fraction of shock energy in electrons, $ε_e$; the fraction of electrons that gets accelerated into a power-law distribution of energies, $ξ_e$; and the minimum Lorentz factor of the accelerated electrons, $γ_m$. These parameters are constrained by observations of the peaks in radio afterglow light curves and spectral energy distributions. From a sample of 49 radio afterglows, we are able to find narrow distributions for these parameters, hinting at possible universality of the blast wave microphysics, although observational bias could play a role in this. Using radio peaks and considerations related to the prompt gamma-ray emission efficiency, we constrain the allowed parameter ranges for both $ε_e$ and $ξ_e$ to within about one order of magnitude, $0.01\lesssimε_e\lesssim0.2$ and $0.1\lesssimξ_e\lesssim1$. Such stringent constraints are inaccessible for $ξ_e$ from broadband studies due to model degeneracies.
description: 10 pages, 6 figures, 2 tables; accepted for publication in MNRAS
Refining the Masses and Radii of the Star Kepler-33 and its Five Transiting Planets
Creators: name: Sikora, James
name: Rowe, Jason
name: Jontof-Hutter, Daniel
name: Lissauer, Jack J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Kepler-33 hosts five validated transiting planets ranging in period from 5 to 41 days. The planets are in nearly co-planar orbits and exhibit remarkably similar (appropriately scaled) transit durations indicative of similar impact parameters. The outer three planets have radii of $3.5\lesssim R_{\rm p}/R_\oplus\lesssim4.7$ and are closely-packed dynamically, and thus transit timing variations can be observed. Photodynamical analysis of transit timing variations provide $2σ$ upper bounds on the eccentricity of the orbiting planets (ranging from $<0.02$ to $<0.2$) and the mean density of the host-star ($0.39_{-0.02}^{+0.01}\,{\rm g/cm^3}$). We combine \emph{Gaia} Early Data Release 3 parallax observations, the previously reported host-star effective temperature and metallicity, and our photodynamical model to refine properties of the host-star and the transiting planets. Our analysis yields well-constrained masses for Kepler-33~e ($6.6_{-1.0}^{+1.1}\,M_\oplus$) and f ($8.2_{-1.2}^{+1.6}\,M_\oplus$) along with $2σ$ upper limits for planets c ($<19\,M_\oplus$) and d ($<8.2\,M_\oplus$). We confirm the reported low bulk densities of planet d ($<0.4\,{\rm g/cm^3}$), e ($0.8\pm0.1\,{\rm g/cm^3}$), and f ($0.7\pm0.1\,{\rm g/cm^3}$). Based on comparisons with planetary evolution models, we find that Kepler-33~e and f exhibit relatively high envelope mass fractions of $f_{\rm env}=7.0_{-0.5}^{+0.6}\%$ and $f_{\rm env}=10.3\pm0.6\%$, respectively. Assuming a mass for planet d $\sim4\,M_\oplus$ suggests that it has $f_{\rm env}\gtrsim12\%$.
description: 15 pages, 11 figures, accepted for publication in AJ
Integral group actions on symmetric spaces and discrete duality symmetries of supergravity theories
Creators: name: Carbone, Lisa
name: Murray, Scott H.
name: Sati, Hisham
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Group Theory (math.GR)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 17B81

description: For $G(\mathbb{R})$ a split, simply connected, semisimple Lie group of rank $n$ and $K$ the maximal compact subgroup of $G$, we give a method for computing Iwasawa coordinates of $G/K$ using the Chevalley generators and the Steinberg presentation. When $G/K$ is a scalar coset for a supergravity theory in dimensions $\geq 3$, we determine the action of the integral form $G(\mathbb{Z})$ on $G/K$. We give explicit results for the action of the discrete $U$--duality groups $SL_2(\mathbb{Z})$ and $E_7(\mathbb{Z})$ on the scalar cosets $SL_2(\mathbb{R})/SO_2(\mathbb{R})$ and $E_{7(+7)}(\mathbb{R})/[SU(8,\mathbb{R})/\{\pm Id\}]$ for type IIB supergravity in ten dimensions and 11--dimensional supergravity in $D=4$ dimensions, respectively. For the former, we use this to determine the discrete U--duality transformations on the scalar sector in the Borel gauge and we describe the discrete symmetries of the dyonic charge lattice. We determine the spectrum--generating symmetry group for fundamental BPS solitons of type IIB supergravity in $D=10$ dimensions at the classical level and we propose an analog of this symmetry at the quantum level. We indicate how our methods can be used to study the orbits of discrete U--duality groups in general.
title: Бухгалтерлік есеп негіздері
Creators: name: ELS IPR BOOKS
Publisher: name: EDP Hub (Идипи Хаб), Профобразование
Year: 2023

description: Оқу құралдың негізгі мақсаты — студенттердің ХҚЕС шот жоспарына көшіруде дағдыны қалыптастыру мен қолдануды жетілдіру. Бухгалтерлік есептің ұғымы, оның шаруашылықты басқарудағы рөлі мен орны қарастырылған; коммерциялық және коммерциялық емес ұйымдарда бухгалтерлік есептің формалары мен ұйымдастырылуы, негізгі есептік санаттар мен қағидаттардың, нысандардың, әдістердің мазмұны. Теоретикалық білімді және тәжірибелік дағдыларды бекіту үшін тәжірибелік сабақты өткізуге арналған материалдар берілген, өзін-өзі бақылау сұрақтары, өздік жұмыстар үшін тапсырмалар мен оларды орындаудың әдістемелік ұсыныстары, өзінің мазмұны бойынша және орындау жүйелігіне қарай байланысты тапсырмалары және есептері бар жұмыс дәптері берілген. Осы оқу құралы тәжірибелік сабақтарды тереңдете жүргізуге жәрдемдеседі. Келтірілген сандық мәліметтер шартты болып табылады. Орта кәсіптік оқу орындарының «Есеп және аудит» мамандығының бағдарламасы негізінде колледж оқытушылары мен студенттеріне арналған.
Partially coherent Airy beams: A cross-spectral density approach
Creators: name: Martínez-Herrero, R.
name: Sanz, A. S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Airy beams are known for displaying shape invariance and self-acceleration along the transverse direction while they propagate forwards. Although these properties could be associated with the beam coherence, it has been revealed that they also manifest in the case of partially coherent Airy-type. Here, these properties are further investigated by introducing and analyzing a class of partially coherent Airy beams under both infinite and finite energy conditions. The key element within the present approach is the so-called cross-spectral density, which enables a direct connection with the quantum density matrix, making the analysis exportable to the quantum realm to study the dynamics of Airy wave packets acted by both incoherence and decoherence. As it is shown, in the case of infinite energy beams both properties are preserved even under the circumstance of total incoherence provided the underlying structure of the beam remains equal to that of an Airy beam. In the case of finite energy beams, a situation closer to a realistic scenario, as experimental beams cannot have an infinite extension, it is shown that a propagation range along which both properties are preserved can be warranted. This is controlled by a critical distance, which depends on the spread range determined by the parameters ruling the extension of random field spatial fluctuations. Such a distance is determined by defining a position-dependent parameter that quantifies the degree of overlapping between the propagated beam and the input one displaced by an amount equivalent to the propagation distance.
description: 13 pages, 6 figures (very minor corrections with respect to previous version)
The discovery of three hot Jupiters, NGTS-23b, 24b and 25b, and updated parameters for HATS-54b from the Next Generation Transit Survey
Creators: name: Jackson, David G.
name: Watson, Christopher A.
name: de Mooij, Ernst J. W.
name: Acton, Jack S.
name: Alves, Douglas R.
name: Anderson, David R.
name: Armstrong, David J.
name: Bayliss, Daniel
name: Belardi, Claudia
name: Bouchy, François
name: Bryant, Edward M.
name: Burleigh, Matthew R.
name: Casewell, Sarah L.
name: Costes, Jean C.
name: Eigmüller, Phillip
name: Goad, Michael R.
name: Gill, Samuel
name: Gillen, Edward
name: Günther, Maximilian N.
name: Hawthorn, Faith
name: Henderson, Beth A.
name: Jackman, James A. G.
name: Jenkins, James S.
name: Lendl, Monika
name: Kendall, Alicia
name: McCormac, James
name: Moyano, Maximiliano
name: Nielsen, Louise. D.
name: Osborn, Ares
name: Sefako, Ramotholo R.
name: Smith, Alexis M. S.
name: Tilbrook, Rosanna H.
name: Turner, Oliver
name: Udry, Stéphane
name: Vines, Jose I.
name: West, Richard G.
name: Wheatley, Peter J.
name: Worters, Hannah
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We report the discovery of three new hot Jupiters with the Next Generation Transit Survey (NGTS) as well as updated parameters for HATS-54b, which was independently discovered by NGTS. NGTS-23b, NGTS-24b and NGTS-25b have orbital periods of 4.076, 3.468, and 2.823 days and orbit G-, F- and K-type stars, respectively. NGTS-24 and HATS-54 appear close to transitioning off the main-sequence (if they are not already doing so), and therefore are interesting targets given the observed lack of Hot Jupiters around sub-giant stars. By considering the host star luminosities and the planets' small orbital separations (0.037 - 0.050 au), we find that all four hot Jupiters are above the minimum irradiance threshold for inflation mechanisms to be effective. NGTS-23b has a mass of 0.61 $M_{J}$ and radius of 1.27 $R_{J}$ and is likely inflated. With a radius of 1.21 $R_{J}$ and mass of 0.52 $M_{J}$, NGTS-24b has a radius larger than expected from non-inflated models but its radius is smaller than the predicted radius from current Bayesian inflationary models. Finally, NGTS-25b is intermediate between the inflated and non-inflated cases, having a mass of 0.64 $M_{J}$ and a radius of 1.02 $R_{J}$. The physical processes driving radius inflation remain poorly understood, and by building the sample of hot Jupiters we can aim to identify the additional controlling parameters, such as metallicity and stellar age.
description: 17 pages, 8 figures. Accepted for publication in MNRAS
Failure of Nehari's Theorem for Multiplicative Hankel Forms in Schatten Classes
Creators: name: Brevig, Ole Fredrik
name: Perfekt, Karl-Mikael
Publisher: name: arXiv
Year: 2014
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: Primary 47B35, Secondary 30B50

description: Ortega-Cerdà -- Seip demonstrated that there are bounded multiplicative Hankel forms which do not arise from bounded symbols. On the other hand, when such a form is in the Hilbert-Schmidt class $\mathcal{S}_2$, Helson showed that it has a bounded symbol. The present work investigates forms belonging to the Schatten classes between these two cases. It is shown that for every $p>(1-\logπ/\log{4})^{-1}$ there exist multiplicative Hankel forms in the Schatten class $\mathcal{S}_p$ which lack bounded symbols. The lower bound on $p$ is in a certain sense optimal when the symbol of the multiplicative Hankel form is a product of homogeneous linear polynomials.
description: Minor typographical changes. This paper has been accepted for publication in Studia Mathematica
Dust temperature uncertainties hamper the inference of dust and molecular gas masses from the dust continuum emission of quiescent high-redshift galaxies
Creators: name: Cochrane, R. K.
name: Hayward, C. C.
name: Anglés-Alcázar, D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Single flux density measurements at observed-frame sub-millimeter and millimeter wavelengths are commonly used to probe dust and gas masses in galaxies. In this Letter, we explore the robustness of this method to infer dust mass, focusing on quiescent galaxies, using a series of controlled experiments on four massive haloes from the Feedback in Realistic Environments (FIRE) project. Our starting point is four star-forming, central galaxies at seven redshifts between z=1.5 and z=4.5. We generate modified quiescent galaxies that have been quenched for 100Myr, 500Myr, or 1Gyr prior to each of the studied redshifts by re-assigning stellar ages. We derive spectral energy distributions for each fiducial and modified galaxy using radiative transfer. We demonstrate that the dust mass inferred is highly dependent on the assumed dust temperature, T_dust, which is often unconstrained observationally. Motivated by recent work on quiescent galaxies that assumed T_dust~25K, we show that the ratio between dust mass and 1.3mm flux density can be higher than inferred by up to an order of magnitude, due to the considerably lower dust temperatures seen in non star-forming galaxies. This can lead to an underestimation of dust mass (and, when sub-mm flux density is used as a proxy for molecular gas content, gas mass). This underestimation is most severe at higher redshifts, where the observed-frame 1.3mm flux density probes rest-frame wavelengths far from the Rayleigh-Jeans regime, and hence depends super-linearly on dust temperature. We fit relations between ratios of rest-frame far-infrared flux densities and mass-weighted dust temperature that can be used to constrain dust temperatures from observations and hence derive more reliable dust and molecular gas masses.
description: 10 pages, 4 figures; accepted for publication in ApJL
Coproducts of proximity spaces
Creators: name: Grzegrzolka, Pawel
Publisher: name: arXiv
Year: 2019
Subjects: subject: General Topology (math.GN)
subject: FOS: Mathematics
subject: 54E05, 54D35

description: In this paper, we introduce coproducts of proximity spaces. After exploring several of their basic properties, we show that given a collection of proximity spaces, the coproduct of their Smirnov compactifications proximally and densely embeds in the Smirnov compactification of the coproduct of the original proximity spaces. We also show that the dense proximity embedding is a proximity isomorphism if and only if the index set is finite. After constructing a number of examples of coproducts and their Smirnov compactifications, we explore several properties of the Smirnov compactification of the coproduct, including its metrizability, connectedness of the boundary, dimension, and its relation to the Stone-Cech compactification. In particular, we show that the Smirnov compactification of the infinite coproduct is never metrizable and that its boundary is highly disconnected. We also show that the proximity dimension of the Smirnov compactification of the coproduct equals the supremum of the covering dimensions of the individual Smirnov compactifications and that the Smirnov compactification of the coproduct is homeomorphic to the Stone-Cech compactification if and only if each individual proximity space is equipped with the Stone-Cech proximity. We finish with an example of a coproduct with the covering dimension $0$ but the proximity dimension $\infty.$
description: 24 pages
SPIRIT Checklist for Efficacy Of Muscle Energy Technique Versus Strain Counterstrain Technique On Pain And Functional Disabilities In The Individuals With Carpal Tunnel Syndrome- A prospective Comparative Study
Creators: name: Kandarkar, Madhavi
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 320216
subject: Orthopaedics

description:
SPIRIT Checklist for Efficacy Of Muscle Energy Technique Versus Strain Counterstrain Technique On Pain And Functional Disabilities In The Individuals With Carpal Tunnel Syndrome- A prospective Comparative Study
A family of non-restricted $D=11$ geometric supersymmetries
Creators: name: Klinker, Frank
Publisher: name: arXiv
Year: 2014
Subjects: subject: Differential Geometry (math.DG)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We construct a two parameter family of eleven-dimensional indecomposable Cahen-Wallach spaces with irreducible, non-flat, non-restricted geometric supersymmetry of fraction $ν=\tfrac{3}{4}$. Its compactified moduli space can be parametrized by a compact interval with two points corresponding to two non-isometric, decomposable spaces. These singular spaces are associated to a restricted $N=4$ geometric supersymmetry with $ν=\tfrac{1}{2}$ in dimension six and a non-restricted $N=2$ geometric supersymmetry with $ν=\tfrac{3}{4}$ in dimension nine.
description: 26pp, v3: compared with the published version we clarified the content of Section 7 and corrected one of the interpretations
The pattern speeds of vertical breathing waves
Creators: name: Khachaturyants, Tigran
name: Debattista, Victor P.
name: Ghosh, Soumavo
name: Silva, Leandro Beraldo e
name: Daniel, Kathryne J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We measure and compare the pattern speeds of vertical breathing, vertical bending, and spiral density waves in two isolated N-body+SPH simulations, using windowed Fourier transforms over 1 Gyr time intervals. We show that the pattern speeds of the breathing waves match those of the spirals but are different from those of the bending waves. We also observe matching pattern speeds between the bar and breathing waves. Our results not only strengthen the case that, throughout the disc, breathing motions are driven by spirals but indeed that the breathing motions are part and parcel of the spirals.
description: 5 pages, 4 figures, published in MNRAS Letters
Constructing the Milky Way Stellar Halo in the Galactic Center by Direct Orbit Integration
Creators: name: Yang, Chengqun
name: Zhu, Ling
name: Tahmasebzadeh, Behzad
name: Xue, Xiang-Xiang
name: Liu, Chao
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The halo stars on highly radial orbits should inevitably pass the center regions of the Milky Way. Under the assumption that the stellar halo is in dynamical equilibrium and axisymmetric, we integrate the orbits of $\sim 10,000$ halo K-giants at $5\leq r \leq 50$ kpc cross-matched from LAMOST DR5 and $Gaia$ DR3. By carefully considering the selection function, we construct the stellar halo distribution at the entire regions of $r \leq 50$ kpc. We find that a double-broken power-law function well describes the stellar halo density distribution with shallower slopes in the inner regions and the two breaks at $r=10$ kpc and $r=25$ kpc, respectively. The stellar halo becomes flatter from outer to inner regions but has $q\sim 0.5$ at $r \lesssim 5$ kpc. The stellar halo becomes isotropic with a slight prograde rotation in the inner 5 kpc, and reaches velocity dispersions of $\sim 250\rm \ km\ s^{-1}$. We get a weak negative metallicity gradient of $-0.005$ dex kpc$^{-1}$ at $5\leq r \leq 50$ kpc, while there is an excess of relative metal-rich stars with [Fe/H]$>-1$ in the inner 10 kpc. The halo interlopers at $r \leq 5$ kpc from integration of our sample has a mass of $\sim1.2 \times 10^8\ M_{\odot}$ ($\sim 4.7 \times 10^7\ M_{\odot}$ at [Fe/H]$<-1.5$), which can explain 50-100% of the metal-poor stars with [Fe/H]$<-1.5$ directly observed in the Galactic central regions.
description: 22 pages, 12 figures, Accepted for publication in AJ
A comparison of the Georgescu and Vasy spaces associated to the N-body problems and applications
Creators: name: Ammann, Bernd
name: Mougel, Jeremy
name: Nistor, Victor
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mathematical Physics (math-ph)
subject: Differential Geometry (math.DG)
subject: Functional Analysis (math.FA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We provide new insight into the analysis of N-body problems by studying a compactification $M_N$ of $\mathbb{R}^{3N}$ that is compatible with the analytic properties of the $N$-body Hamiltonian $H_N$. We show that our compactification coincides with the compactification introduced by Vasy using blow-ups in order to study the scattering theory of N-body Hamiltonians and with a compactification introduced by Georgescu using $C^*$-algebras. In particular, the compactifications introduced by Georgescu and by Vasy coincide (up to a homeomorphism that is the identity on $\mathbb{R}^{3N}$). Our result has applications to the spectral theory of $N$-body problems and to some related approximation properties. For instance, results about the essential spectrum, the resolvents, and the scattering matrices of $H_N$ (when they exist) may be related to the behavior near $M_N\setminus \mathbb{R}^{3N}$ (i.e. "at infinity") of their distribution kernels, which can be efficiently studied using our methods. The compactification $M_N$ is compatible with the action of the permutation group $S_N$, which allows to implement bosonic and fermionic (anti-)symmetry relations. We also indicate how our results lead to a regularity result for the eigenfunctions of $H_N$.
description: In version 2 several application towards physics were added, according to the wishes of the journal. The numbering has changed. In version 3 several formulations were improved, however the mathematical content is unchanged. Again the numbering has changed. The article was accepted in Annales Henri Poincare
Discontinuous Buckling of Wide Beams and Metabeams
Creators: name: Coulais, Corentin
name: Overvelde, Johannes T. B.
name: Lubbers, Luuk A.
name: Bertoldi, Katia
name: van Hecke, Martin
Publisher: name: arXiv
Year: 2014
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We uncover how nonlinearities dramatically alter the buckling of elastic beams. First, we show experimentally that sufficiently wide ordinary elastic beams and specifically designed metabeams ---beams made from a mechanical metamaterial--- exhibit discontinuous buckling, an unstable form of buckling where the post-buckling stiffness is negative. Then we use simulations to uncover the crucial role of nonlinearities, and show that beams made from increasingly nonlinear materials exhibit increasingly negative post-buckling slope. Finally, we demonstrate that for sufficiently strong nonlinearity, we can observe discontinuous buckling for metabeams as slender as $1\%$ numerically and $5\%$ experimentally.
description: 5 pages, 5 figures. See http://corentincoulais.wordpress.com/movies/metabeam-movies/ for movies. 2 pages of SI
Josephson Effect in NbS$_{2}$ van der Waals Junctions
Creators: name: Zhao, Chuanwen
name: Yi, Xin
name: Chen, Qiao
name: Yan, Chengyu
name: Wang, Shun
Publisher: name: arXiv
Year: 2022
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Van der Waals (vdW) Josephson junctions can possibly accelerate the development of advanced superconducting device that utilizes the unique properties of two-dimensional (2D) transition metal dichalcogenide (TMD) superconductors such as spin-orbit coupling, spin-valley locking. Here, we fabricate vertically stacked NbS$_{2}$/NbS$_{2}$ Josephson junctions using a modified all-dry transfer technique and characterize the device performance via systematic low-temperature transport measurements. The experimental results show that the superconducting transition temperature of the NbS$_{2}$/NbS$_{2}$ Josephson junction is 5.84 K, and the critical current density reaches 3975 A/cm$^{2}$ at 2K. Moreover, we extract a superconducting energy gap $Δ=0.58$ meV, which is considerably smaller than that expected from the single band s-wave Bardeen-Cooper-Schrieffer (BCS) model ($Δ=0.89$ meV).
Weyl group orbits on Kac--Moody root systems
Creators: name: Carbone, Lisa
name: Conway, Alexander
name: Freyn, Walter
name: Penta, Diego
Publisher: name: arXiv
Year: 2014
Subjects: subject: Group Theory (math.GR)
subject: High Energy Physics - Theory (hep-th)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 17B81

description: Let $\mathcal{D}$ be a Dynkin diagram and let $Π=\{α_1,\dots ,α_{\ell}\}$ be the simple roots of the corresponding Kac--Moody root system. Let $\mathfrak{h}$ denote the Cartan subalgebra, let $W$ denote the Weyl group and let $Δ$ denote the set of all roots. The action of $W$ on $\mathfrak{h}$, and hence on $Δ$, is the discretization of the action of the Kac--Moody algebra. Understanding the orbit structure of $W$ on $Δ$ is crucial for many physical applications. We show that for $i\neq j$, the simple roots $α_i$ and $α_j$ are in the same $W$--orbit if and only if vertices $i$ and $j$ in the Dynkin diagram corresponding to $α_i$ and $α_j$ are connected by a path consisting only of single edges. We introduce the notion of `the Cayley graph $\mathcal{P}$ of the Weyl group action on real roots' whose connected components are in one-to-one correspondence with the disjoint orbits of $W$. For a symmetric hyperbolic generalized Cartan matrix $A$ of rank $\geq 4$ we prove that any 2 real roots of the same length lie in the same $W$--orbit. We show that if the generalized Cartan matrix $A$ contains zeros, then there are simple roots that are stabilized by simple root reflections in $W$, that is, $W$ does not act simply transitively on real roots. We give sufficient conditions in terms of the generalized Cartan matrix $A$ (equivalently ${\mathcal D}$) for $W$ to stabilize a real root. Using symmetry properties of the imaginary light cone in the hyperbolic case, we deduce that the number of $W$--orbits on imaginary roots on a hyperboloid of fixed radius is bounded above by the number of root lattice points on the hyperboloid that intersect the closure of the fundamental region for $W$.
Spectroscopic follow-up of a sub-set of the Gaia/IPHAS catalogue of Hα-excess sources
Creators: name: Fratta, M.
name: Scaringi, S.
name: Monguió, M.
name: Pala, A. F.
name: Drew, J. E.
name: Knigge, C.
name: Iłkiewicz, K. A.
name: Gandhi, P.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: State-of-the-art techniques to identify Hαemission line sources in narrow-band photometric surveys consist of searching for Hαexcess with reference to nearby objects in the sky (position-based selection). However, while this approach usually yields very few spurious detections, it may fail to select intrinsically faint and/or rare Hα-excess sources. In order to obtain a more complete representation of the heterogeneous emission line populations, we recently developed a technique to find outliers relative to nearby objects in the colour-magnitude diagram (CMD-based selection). By combining position-based and CMD-based selections, we built an updated catalogue of Hα-excess candidates in the northern Galactic Plane. Here we present spectroscopic follow-up observations and classification of 114 objects from this catalogue, that enable us to test our novel selection method. Out of the 70 spectroscopically confirmed Hαemitters in our sample, 15 were identified only by the CMD-based selection, and would have been thus missed by the classic position-based technique. In addition, we explore the distribution of our spectroscopically confirmed emitters in the Gaia CMD. This information can support the classification of emission line sources in large surveys, such as the upcoming WEAVE and 4MOST, especially if augmented with the introduction of other colours.
description: 13 pages, 8 figures
Positioning of Multiple Unmanned Aerial Vehicle Base Stations in future Wireless Network
Creators: name: Sivalingam, Thushan
name: Manosha, K. B. Shashika
name: Rajatheva, Nandana
name: Latva-aho, M.
name: Dissanayake, Maheshi B.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Signal Processing (eess.SP)
subject: Optimization and Control (math.OC)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Mathematics

description: Unmanned aerial vehicle (UAV) base stations (BSs) are reliable and efficient alternative to full fill the coverage and capacity requirements when the backbone network fails to provide such requirements due to disasters. In this paper, we consider optimal UAV-deployment problem in 3D space for a mmWave network. The objective is to deploy multiple aerial BSs simultaneously to completely serve the ground users. We develop a novel algorithm to find the feasible positions for a set of UAV-BSs from a predefined set of locations, subject to a signal-to-interference-plus-noise ratio (SINR) constraint of every associated user, UAV-BS's limited hovering altitude constraint and restricted operating zone constraint. We cast this 3D positioning problem as an l_0 minimization problem. This is a combinatorial, NP-hard problem. We approximate the l_0 minimization problem as non-combinatorial l_1-norm problem. Therefore, we provide a suboptimal algorithm to find a set of feasible locations for the UAV-BSs to operate. The analysis shows that the proposed algorithm achieves a set of the location to deploy multiple UVA-BSs simultaneously while satisfying the constraints.
Implicit Higher-Order Moment Matching Technique for Model Reduction of Quadratic-bilinear Systems
Creators: name: Asif, Mian Muhammad Arsalan
name: Ahmad, Mian Ilyas
name: Benner, Peter
name: Feng, Lihong
name: Stykel, Tatjana
Publisher: name: arXiv
Year: 2019
Subjects: subject: Systems and Control (eess.SY)
subject: Analysis of PDEs (math.AP)
subject: Dynamical Systems (math.DS)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Mathematics
subject: 35G50

description: We propose a projection based multi-moment matching method for model order reduction of quadratic-bilinear systems. The goal is to construct a reduced system that ensures higher-order moment matching for the multivariate transfer functions appearing in the input-output representation of the nonlinear system. An existing technique achieves this for the first two multivariate transfer functions, in what is called the symmetric form of the multivariate transfer functions. We extend this framework to an equivalent and simplified form, the regular form, which allows us to show moment matching for the first three multivariate transfer functions. Numerical results for three benchmark examples of quadratic-bilinear systems show that the proposed framework exhibits better performance with reduced computational cost in comparison to existing techniques.
description: 19 pages, 11 subfigures in 6 figures, Journal
20 Master 1 – Diplôme Universitaire en Sciences de l'Information et des Bibliothèques Les serious games en bibliothèque pour l'appropriation des compétences informationnelles par les lycéens
Creators: name: Weber, Corinne
Publisher: name: Zenodo
Year: 2021
Subjects: Compétences informationnelles, CDI, bibliothèques, formations

description: Résumé : Ce mémoire démontre en quoi l’utilisation de serious games est profitable dans un cours de formation aux compétences informationnelles destiné aux lycéens (16 - 20 ans) en fonction de 4 aspects: psychologique, kinesthésique, ludique et social. Il propose quelques pistes permettant d’intégrer les serious games dans les formations aux compétences informationnelles données par les bibliothécaires. This diploma’s dissertation explains why and how, according to psychological, kinesthetic, playful and social factors, it is appropriate to use serious games in a library class in order to develop the students’ information literacy skills (16 - 20 years old). It presents a few ideas allowing the use of serious games in a library class.
Efficient Computation of Instantons for Multi-Dimensional Turbulent Flows with Large Scale Forcing
Creators: name: Grafke, Tobias
name: Grauer, Rainer
name: Schindel, Stephan
Publisher: name: arXiv
Year: 2014
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Extreme events play a crucial role in fluid turbulence. Inspired by methods from field theory, these extreme events, their evolution and probability can be computed with help of the instanton formalism as minimizers of a suitable action functional. Due to the high number of degrees of freedom in multi-dimensional fluid flows, traditional global minimization techniques quickly become prohibitive in their memory requirements. We outline a novel method for finding the minimizing trajectory in a wide class of problems that typically occurs in turbulence setups, where the underlying dynamical system is a non-gradient, non-linear partial differential equation, and the forcing is restricted to a limited length scale. We demonstrate the efficiency of the algorithm in terms of performance and memory by computing high resolution instanton field configurations corresponding to viscous shocks for 1D and 2D compressible flows.
Mobility edges and critical regions in periodically kicked incommensurate optical Raman lattice
Creators: name: Wang, Yucheng
Publisher: name: arXiv
Year: 2022
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Conventionally the mobility edge (ME) separating extended states from localized ones is a central concept in understanding Anderson localization transition. The critical state, being delocalized and non-ergodic, is a third type of fundamental state that is different from both the extended and localized states. Here we study the localization phenomena in a one dimensional periodically kicked quasiperiodic optical Raman lattice by using fractal dimensions. We show a rich phase diagram including the pure extended, critical and localized phases in the high frequency regime, the MEs separating the critical regions from the extended (localized) regions, and the coexisting phase of extended, critical and localized regions with increasing the kicked period. We also find the fragility of phase boundaries, which are more susceptible to the dynamical kick, and the phenomenon of the reentrant localization transition. Finally, we demonstrate how the studied model can be realized based on current cold atom experiments and how to detect the rich physics by the expansion dynamics. Our results provide insight into studying and detecting the novel critical phases, MEs, coexisting quantum phases, and some other physics phenomena in the periodically kicked systems.
description: To appear in PRA
Finding binary words with a given number of subsequences
Creators: name: Żak, Radosław
Publisher: name: arXiv
Year: 2022
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We relate binary words with a given number of subsequences to continued fractions of rational numbers with a given denominator. We deduce that there are binary strings of length $O(\log n \log \log n)$ with exactly $n$ subsequences; this can be improved to $O(\log n)$ under assumption of Zaremba's conjecture.