cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Real-Time Trajectory Replanning for MAVs using Uniform B-splines and a 3D Circular Buffer
Creators: name: Usenko, Vladyslav
name: von Stumberg, Lukas
name: Pangercic, Andrej
name: Cremers, Daniel
Publisher: name: arXiv
Year: 2017
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: In this paper, we present a real-time approach to local trajectory replanning for microaerial vehicles (MAVs). Current trajectory generation methods for multicopters achieve high success rates in cluttered environments, but assume that the environment is static and require prior knowledge of the map. In the presented study, we use the results of such planners and extend them with a local replanning algorithm that can handle unmodeled (possibly dynamic) obstacles while keeping the MAV close to the global trajectory. To ensure that the proposed approach is real-time capable, we maintain information about the environment around the MAV in an occupancy grid stored in a three-dimensional circular buffer, which moves together with a drone, and represent the trajectories by using uniform B-splines. This representation ensures that the trajectory is sufficiently smooth and simultaneously allows for efficient optimization.
Soil Health & Soil Heritage Project - Workshop Reports
Creators: name: Opitz, Rachel
Publisher: name: Zenodo
Year: 2022
Subjects: archaeology
soil health
precision agriculture
remote sensing
land management

description: This archive contains reports on workshops organised by the Soil Health & Soil Heritage Project. It mirrors content linked from the ipaast-czo project website. This project aimed to build links between groups exploring how soils in farmed landscapes are qualified, studied, modelled, and valued from different perspectives: agricultural, environmental, and archaeological. It focused on data created through remote and near-surface sensing technologies to provide an impetus for cross-disciplinary conversations, because these data have the potential to serve as a shared resource for research and management. The project aimed to identify shared research and management priorities related to soil health and soil heritage in agricultural landscapes, to evaluate the capability of commercial and experimental sensors to provide data to address these shared priorities, and to identify barriers to the creation of interoperable remote and near-surface sensing data resources on soils and their role in agricultural systems. The project was led by a group of researchers at the University of Glasgow, working on initiatives including agri-environment sensing projects in CENSIS, the Global Soil Heath network, and the ipaast-czo project on archaeological remote and near-surface sensing. In 2022, the project reviewed instruments to assess their suitability for cross-domain data collection and ran two workshops, in Dalswinton and Glasgow, to build a research and practice network focused on sensing methods for soils.
Twisting Dirac fermions: Circular dichroism in bilayer graphene
Creators: name: Morell, E. Suarez
name: Chico, Leonor
name: Brey, Luis
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Twisted bilayer graphene is a chiral system which has been recently shown to present circular dichroism. In this work we show that the origin of this optical activity is the rotation of the Dirac fermions' helicities in the top and bottom layer. Starting from the Kubo formula, we obtain a compact expression for the Hall conductivity that takes into account the dephasing of the electromagnetic field between the top and bottom layers and gathers all the symmetries of the system. Our results are based in both a continuum and a tight-binding model, and they can be generalized to any two-dimensional Dirac material with a chiral stacking between layers.
The Birth of Collective Memories: Analyzing Emerging Entities in Text Streams
Creators: name: Graus, David
name: Odijk, Daan
name: de Rijke, Maarten
Publisher: name: arXiv
Year: 2017
Subjects: subject: Information Retrieval (cs.IR)
subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: We study how collective memories are formed online. We do so by tracking entities that emerge in public discourse, that is, in online text streams such as social media and news streams, before they are incorporated into Wikipedia, which, we argue, can be viewed as an online place for collective memory. By tracking how entities emerge in public discourse, i.e., the temporal patterns between their first mention in online text streams and subsequent incorporation into collective memory, we gain insights into how the collective remembrance process happens online. Specifically, we analyze nearly 80,000 entities as they emerge in online text streams before they are incorporated into Wikipedia. The online text streams we use for our analysis comprise of social media and news streams, and span over 579 million documents in a timespan of 18 months. We discover two main emergence patterns: entities that emerge in a "bursty" fashion, i.e., that appear in public discourse without a precedent, blast into activity and transition into collective memory. Other entities display a "delayed" pattern, where they appear in public discourse, experience a period of inactivity, and then resurface before transitioning into our cultural collective memory.
description: To appear in JASIST
Transition probability generating function of a transitionless quantum parametric oscillator
Creators: name: Mishima, Hiroaki
name: Izumida, Yuki
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The transitionless tracking (TT) algorithm enables the exact tracking of quantum adiabatic dynamics in an arbitrary short time by adding a counterdiabatic Hamiltonian to the original adiabatic Hamiltonian. By applying Husimi's method originally developed for a quantum parametric oscillator (QPO) to the transitionless QPO achieved using the TT algorithm, we obtain the transition probability generating function with a time-dependent parameter constituted with solutions of the corresponding classical parametric oscillator (CPO). By obtaining the explicit solutions of this CPO using the phase-amplitude method, we find that the time-dependent parameter can be reduced to the frequency ratio between the Hamiltonians without and with the counterdiabatic Hamiltonian, from which we can easily characterize the result achieved by the TT algorithm. We illustrate our theory by showing the trajectories of the CPO on the classical phase space, which elucidate the effect of the counterdiabatic Hamiltonian of the QPO.
description: 13 pages, 3 figures
Darkness without dark matter and energy -- generalized unimodular gravity
Creators: name: Barvinsky, A. O.
name: Kamenshchik, A. Yu.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We suggest a Lorentz non-invariant generalization of the unimodular gravity theory, which is classically equivalent to general relativity with a locally inert (devoid of local degrees of freedom) perfect fluid having an equation of state with a constant parameter $w$. For the range of $w$ near $-1$ this dark fluid can play the role of dark energy, while for $w=0$ this dark dust admits spatial inhomogeneities and can be interpreted as dark matter. We discuss possible implications of this model in the cosmological initial conditions problem. In particular, this is the extension of known microcanonical density matrix predictions for the initial quantum state of the closed cosmology to the case of spatially open Universe, based on the imitation of the spatial curvature by the dark fluid density. We also briefly discuss quantization of this model necessarily involving the method of gauge systems with reducible constraints and the effect of this method on the treatment of recently suggested mechanism of vacuum energy sequestering.
description: 11 pages, final version, to be published in Physics Letters B
title: Beziehung als Grundlage für Gleichheit
Creators: name: Antony Cruze, Edmond
Year: 2023

description: Alle Menschen sind gleich. Die Menschen haben das Recht, als Gleiche miteinander zu leben und in Beziehung zu treten. Real gesehen existiert die Gleichheit jedoch nicht immer. Z.B. in einer Pflegesituation entsteht eine Ungleichheit zwischen Patient und Arzt. Auch im Sozialsystem gibt es an vielen Orten auch strukturelle Ungleichheit, die weite Bereiche des Lebens beeinflusst. Über Generationen hinweg werden Menschen in Indien durch das Kastensystem gespaltet, gefoltert und ermordet. Giovanni Maio, ein gefragter Ethik-Experte aus der Universität Freiburg versucht die Ungleichheit zwischen Arzt und Patient im Kontext der medizinischen Ethik aufzuheben und stellt dazu die Gestaltung der Beziehung zwischen beiden als Möglichkeit vor, um die ursprüngliche Gleichheit herzustellen. Diese Masterarbeit bezieht sich auf die Überlegungen G. Maios und auf die Enzyklika ‚Fratelli tutti‘ von Papst Franziskus und untersucht, ob diese im Alltag des indischen Kastensystems einen Ansatz bieten könnten, um in der Praxis an der Überwindung der Ungleichheit zu arbeiten, die das Kastensystem unter den Menschen bewirkt.
description: All human beings are equal. People have the right to live and relate to each other as equals. In reality, however, equality does not always exist. For example, in a care situation, inequality arises between the patient and the doctor. In the social system too, there is also structural inequality in many places, which affects wide areas of life. For generations, people in India are divided, tortured and murdered by the caste system. Giovanni Maio, a sought-after ethics expert from the University of Fribourg, seeks to address the inequality between doctor and patient in the context of medical ethics by presenting the shaping of the relationship between the two as a way to establish the original equality. This Master's thesis refers to G. Maio's reflections and to Pope Francis' encyclical 'Fratelli tutti' and examines whether these could offer an approach in the everyday life of the Indian caste system to work in practice on overcoming the inequality that the caste system brings about among people.
The average size of the kernel of a matrix and orbits of linear groups
Creators: name: Rossmann, Tobias
Publisher: name: arXiv
Year: 2017
Subjects: subject: Number Theory (math.NT)
subject: Combinatorics (math.CO)
subject: Group Theory (math.GR)
subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 15B33, 05A15, 11M41, 11S80, 20D60, 20D15, 20E45

description: Let $\mathfrak{O}$ be a compact discrete valuation ring of characteristic zero. Given a module $M$ of matrices over $\mathfrak{O}$, we study the generating function encoding the average sizes of the kernels of the elements of $M$ over finite quotients of $\mathfrak{O}$. We prove rationality and establish fundamental properties of these generating functions and determine them explicitly for various natural families of modules $M$. Using $p$-adic Lie theory, we then show that special cases of these generating functions enumerate orbits and conjugacy classes of suitable linear pro-$p$ groups.
description: 50 pages; expanded version
Exact Virasoro Blocks from Wilson Lines and Background-Independent Operators
Creators: name: Fitzpatrick, A. Liam
name: Kaplan, Jared
name: Li, Daliang
name: Wang, Junpu
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Aspects of black hole thermodynamics and information loss can be derived as a consequence of Virasoro symmetry. To bolster the connection between Virasoro conformal blocks and AdS$_3$ quantum gravity, we study sl$(2)$ Chern-Simons Wilson line networks and revisit the idea that they compute a variety of CFT$_2$ observables, including Virasoro OPE blocks, exactly. We verify this in the semiclassical large central charge limit and to low orders in a perturbative $1/c$ expansion. Wilson lines connecting the boundary to points in the bulk play a natural role in bulk reconstruction. Because quantum gravity in AdS$_3$ is rigidly fixed by Virasoro symmetry, we argue that sl$(2)$ Wilson lines provide building blocks for background independent bulk reconstruction. In particular, we show explicitly that they automatically compute the uniformizing coordinates appropriate to any background state.
description: V3- Added some references V2- Significantly Expanded Appendix on Regulation; 32+21 pages
Transport properties of iron at the Earth's core conditions: the effect of spin disorder
Creators: name: Drchal, V.
name: Kudrnovský, J.
name: Wagenknecht, D.
name: Turek, I.
name: Khmelevskyi, S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The electronic and thermal transport properties of the Earth's core are crucial for many geophysical models such as the geodynamo model of the Earth's magnetic field and of its reversals. Here we show, by considering bcc-iron and iron-rich iron-silicon alloy as a representative of the Earth's core composition and applying the first-principles modeling that the spin disorder at the Earth's core conditions provides an essential contribution, of order 20~$μΩ$\,cm, to the electrical resistivity. This value is comparable in magnitude with the electron-phonon and with the recently estimated electron-electron scattering contributions. The origin of the spin-disorder resistivity (SDR) consists in the existence of fluctuating local moments that are stabilized at high temperatures by the magnetic entropy even at pressures at which the ground state of iron is non-magnetic. We find that electron-phonon and SDR contributions are not additive at high temperatures. We thus observe a large violation of the Matthiessen rule, not common in conventional metallic alloys at ambient conditions.
description: 4 figures
Dark Matter "Transporting" Mechanism Explaining Positron Excesses
Creators: name: Kim, Doojin
name: Park, Jong-Chul
name: Shin, Seodong
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We propose a novel mechanism to explain the positron excesses, which are observed by satellite-based telescopes including PAMELA and AMS-02, in dark matter (DM) scenarios. The novelty behind the proposal is that it makes direct use of DM around the Galactic Center where DM populates most densely, allowing us to avoid tensions from cosmological and astrophysical measurements. The key ingredients of this mechanism include DM annihilation into unstable states with a very long laboratory-frame life time and their "retarded" decay near the Earth to electron-positron pair(s) possibly with other (in)visible particles. We argue that this sort of explanation is not in conflict with relevant constraints from big bang nucleosynthesis and cosmic microwave background. Regarding the resultant positron spectrum, we provide a generalized source term in the associated diffusion equation, which can be readily applicable to any type of two-"stage" DM scenarios wherein production of Standard Model particles occurs at completely different places from those of DM annihilation. We then conduct a data analysis with the recent AMS-02 data to validate our proposal.
description: 14 pages, 3 figures
Length scale of puddle formation in compensation-doped semiconductors and topological insulators
Creators: name: Bömerich, Thomas
name: Lux, Jonathan
name: Feng, Qingyufei Terenz
name: Rosch, Achim
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In most semiconductors and insulators the presence of a small density of charged impurities cannot be avoided, but their effect can be reduced by compensation doping, i.e. by introducing defects of opposite charge. Screening in such a system leads to the formation of electron-hole puddles, which dominate bulk transport, as first recognized by Efros and Shklovskii. Metallic surface states of topological insulators (TI) contribute extra screening channels, suppressing puddles. We investigate the typical length $l_p$, which determines the distance between puddles and the suppression of puddle formation close to metallic surfaces in the limit where the gap $Δ$ is much larger than the typical Coulomb energy $E_c$ of neighboring dopants, $Δ\gg E_c$. In particular, this is relevant for three dimensional Bi-based topological insulators, where $Δ/E_c \sim 100$. Scaling arguments predict $l_p \sim (Δ/E_c)^2$. In contrast, we find numerically that $l_p$ is much smaller and grows in an extended crossover regime approximately linearly with $Δ/E_c$ for numerically accessible values, $Δ/E_c \lesssim 35$. We show how a quantitative scaling argument can be used to extrapolate to larger $Δ/E_c$, where $l_p \sim (Δ/E_c)^2/\ln(Δ/E_c)$. Our results can be used to predict a characteristic thickness of TI thin films, below which the sample quality is strongly enhanced.
description: new version with substantially changed interpretation of numerical results, new first author
Canonical RDEs and general semimartingales as rough paths
Creators: name: Chevyrev, Ilya
name: Friz, Peter K.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 60H99 (Primary) 60H10 (Secondary)

description: In the spirit of Marcus canonical stochastic differential equations, we study a similar notion of rough differential equations (RDEs), notably dropping the assumption of continuity prevalent in the rough path literature. A new metric is exhibited in which the solution map is a continuous function of the driving rough path and a so-called path function, which directly models the effect of the jump on the system. In a second part, we show that general multidimensional semimartingales admit canonically defined rough path lifts. An extension of Lépingle's BDG inequality to this setting is given, and in turn leads to a number of novel limit theorems for semimartingale driven differential equations, both in law and in probability, conveniently phrased via Kurtz-Protter's uniformly-controlled-variations (UCV) condition. A number of examples illustrate the scope of our results.
description: Added details to several sections. Accepted version to appear in Annals of Probability
Prototypes of People with Depression
Creators: name: Ziano, Ignazio
Publisher: name: OSF Registries
Year: 2023
Subjects: subject: Social and Behavioral Sciences
subject: depression
subject: prototypes

description: This registration contains materials, data, and analyses for the paper "Prototypes of People with Depression". This paper investigates the content and the consequences of the prototypes of people with depression in a multi-method fashion. Fourteen preregistered studies (total N = 5023, with U.S. American, British, and French adult participants) show that laypeople consider people with depression as having specific psychological, social, and physical features (e.g., unattractive, overweight, unsuccessful, introverted). Target prototypicality influences how much laypeople believe others have depression, how much observers believe that depression-like symptoms cause someone to experience psychological pain, and how much professional mental healthcare is appropriate for others. This effect was not reduced by instructing people to focus on the symptoms and ignore the target features, yet weakly reduced by informing them of the effect. We discuss theoretical implications for the understanding of prototypes of people with depression and practical implications for alleviating the impact of prototypes.
Low Dimensional Embedding of Climate Data for Radio Astronomical Site Testing in the Colombian Andes
Creators: name: Molano, Germán Chaparro
name: Suárez, Oscar Leonardo Ramírez
name: Restrepo, Oscar
name: Martínez, Alexander
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We set out to evaluate the potential of the Colombian Andes for millimeter-wave astronomical observations. Previous studies for astronomical site testing in this region have suggested that nighttime humidity and cloud cover conditions make most sites unsuitable for professional visible-light observations. Millimeter observations can be done during the day, but require that the precipitable water vapor column above a site stays below $\sim$10 mm. Due to a lack of direct radiometric or radiosonde measurements, we present a method for correlating climate data from weather stations to sites with a low precipitable water vapor column. We use unsupervised learning techniques to low-dimensionally embed climate data (precipitation, rain days, relative humidity, and sunshine duration) in order to group together stations with similar long-term climate behavior. The data were taken over a period of 30 years by 2046 weather stations across the Colombian territory. We find 6 regions with unusually dry, clear-sky conditions, ranging in elevations from 2200 to 3800 masl. We evaluate the suitability of each region using a quality index derived from a Bayesian probabilistic analysis of the station type and elevation distributions. Two of these regions show a high probability of having an exceptionally low precipitable water vapor column. We compared our results with global precipitable water vapor maps and find a plausible geographical correlation with regions with low water vapor columns ($\sim10$ mm) at an accuracy of $\sim20$ km. Our methods can be applied to similar datasets taken in other countries as a first step toward astronomical site evaluation.
description: 29 pages, 17 figures, accepted in PASP, high resolution version at https://github.com/saint-germain/ideam/blob/master/pasp/paperclimate.pdf
Stochastic Maps, Continuous Approximation and Stable Distribution
Creators: name: Kessler, David A.
name: Burov, Stanislav
Publisher: name: arXiv
Year: 2016
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A continuous approximation framework for non-linear stochastic as well as deterministic discrete maps is developed. For the stochastic map with uncorelated Gaussian noise, by successively applying the Itô lemma, we obtain a Langevin type of equation. Specifically, we show how non-linear maps give rise to a Langevin description that involves multiplicative noise. The multiplicative nature of the noise induces an additional effective force, not present in the absence of noise. We further exploit the continuum description and provide an explicit formula for the stable distribution of the stochastic map and conditions for its existence. Our results are in good agreement with numerical simulations of several maps.
description: Phys. Rev. E 2017
Phase transitions in Restricted Boltzmann Machines with generic priors
Creators: name: Barra, Adriano
name: Genovese, Giuseppe
name: Sollich, Peter
name: Tantari, Daniele
Publisher: name: arXiv
Year: 2016
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Machine Learning (cs.LG)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Machine Learning (stat.ML)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We study Generalised Restricted Boltzmann Machines with generic priors for units and weights, interpolating between Boolean and Gaussian variables. We present a complete analysis of the replica symmetric phase diagram of these systems, which can be regarded as Generalised Hopfield models. We underline the role of the retrieval phase for both inference and learning processes and we show that retrieval is robust for a large class of weight and unit priors, beyond the standard Hopfield scenario. Furthermore we show how the paramagnetic phase boundary is directly related to the optimal size of the training set necessary for good generalisation in a teacher-student scenario of unsupervised learning.
description: 5 pages, 4 figures; extensive simulations and 2 new figures added; corrected typos; added references
Parallel tempering algorithm for integration over Lefschetz thimbles
Creators: name: Fukuma, Masafumi
name: Umeda, Naoya
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The algorithm based on integration over Lefschetz thimbles is a promising method to resolve the sign problem for complex actions. However, this algorithm often meets a difficulty in actual Monte Carlo calculations because the configuration space is not easily explored due to the infinitely high potential barriers between different thimbles. In this paper, we propose to use the flow time of the antiholomorphic gradient flow as an auxiliary variable for the highly multimodal distribution. To illustrate this, we implement the parallel tempering method by taking the flow time as a tempering parameter. In this algorithm, we can take the maximum flow time to be sufficiently large such that the sign problem disappears there, and two separate modes are connected through configurations at small flow times. To exemplify that this algorithm does work, we investigate the (0+1)-dimensional massive Thirring model at finite density and show that our algorithm correctly reproduces the analytic results for large flow times such as T=2.
description: 14 pages, 5 figures. v2: typos corrected, figures updated. v3: title changed, references added, typos corrected
On the $η$ and $η'$ Photoproduction Beam Asymmetry at High Energies
Creators: name: Mathieu, V.
name: Nys, J.
name: Fernández-Ramírez, C.
name: Jackura, A.
name: Mikhasenko, M.
name: Pilloni, A.
name: Szczepaniak, A. P.
name: Fox, G.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We show that, in the Regge limit, beam asymmetries in $η$ and $η'$ photoproduction are sensitive to hidden strangeness components. Under reasonable assumptions about the couplings we estimate the contribution of the $ϕ$ Regge pole, which is expected to be the dominant hidden strangeness contribution. The ratio of the asymmetries in $η'$ and $η$ production is estimated to be close to unity in the forward region $0 < -t/\text{GeV}^2 \leq 1$ at the photon energy $E_\text{lab} = 9$~GeV, relevant for the upcoming measurements at Jefferson Lab.
description: 9 pages, 4 figures
Investigation of Icephobic Coatings for Supercooling Heat Exchangers under Submerged Conditions Using Ice Detection Equipment
Creators: name: Frandsen, Jens R.
name: Losada, Ricardo
name: Carbonell, Daniel
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Space Science
subject: Medicine
subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Astronomical and Space Sciences not elsewhere classified
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified

description: By using ice slurry generated through a supercooler as storage, it is possible to reduce energy consumption due to high energy density and heat transfer rate along with the phase change. The supercooled water will then be disturbed to create ice crystals in a crystallizer. The main challenge is to prevent the formation of ice in the supercooler since this leads to its blockage. One aim of the European H2020 TRI-HP project is to develop icephobic coatings for supercoolers, that promote high-water supercooling and avoid the formation of ice. In this study, three coatings to prevent or depress freezing in supercoolers are investigated. Specialized equipment for testing freezing on submerged surfaces has been developed, and the results have been correlated to standard surface properties like roughness and contact angle. It was found that the submerged surfaces do not necessarily follow normal icing theory, where freeze depression is related to contact angle. Instead, it is believed that the mobility of surface additives in amphiphilic coatings has an important role.
Barjols, à proximité de l'hôpital (actuelle Maison régionale de l'eau), les chevaux des gardians boivent à la fontaine
Creators: name: Musée National Des Arts Et Traditions Populaires (Paris)
name: Centre D'ethnologie Française
Publisher: name: École des Hautes Études en Sciences Sociales; Institut  interdisciplinaire d'anthropologie du contemporain (Paris); Laboratoire d'anthropologie et d'histoire de l'institution de la culture (Paris)
Year: 2024

Abstract
A formula for the Entropy of the Convolution of Gibbs probabilities on the circle
Creators: name: Lopes, Artur O.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Dynamical Systems (math.DS)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 37D35, 37E10

description: Consider the transformation $T:S^1 \to S^1$, such that $T(x)=2\, x$ (mod 1), and where $S^1$ is the unitary circle. Suppose $J:S^1 \to \mathbb{R}$ is Holder continuous and positive, and moreover that, for any $y\in S^1$, we have that $\sum_{x\,\,\text{such that}\,\,\, T(x)= y} \, J(x)=1.$ We say that $ρ$ is a Gibbs probability for the Holder continuous potential $\log J$, if $\mathcal{L}_{\log J}^* \,(ρ)=ρ,$ where $\mathcal{L}_{\log J}$ is the Ruelle operator for $\log J$. We call $J$ the Jacobian of $ρ$. Suppose $ν=μ_1*μ_2$ is the convolution of two Gibbs probabilities $μ_1$ and $μ_2$ associated, respectively, to $\log J_1$ and $\log J_2$. We show that $ν$ is also Gibbs and its Jacobian $\tilde{J}$ is given by $\tilde{J}(u) = \int J_1(u-x) d μ_2(x)$ In this case, the entropy $h(ν)$ is given by the expression $$ h(ν) = - \int\,[\,\,\int\, \log \,(\,\int J_1(r+s-x) d μ_2(x)\,) \, d μ_2(r)\,\, ]\,\,d μ_1 (s).$$ For a fixed $μ_2$ we consider differentiable variations $μ_1^t$, $t \in (-ε,ε)$, of $μ_1$ on the Banach manifold of Gibbs probabilities, where $μ_1^0=μ_1$, and we estimate the derivative of the entropy $h(μ_1^t * μ_2)$ at $t=0$. We also present an expression for the Jacobian of the convolution of a Gibbs probability $ρ$ with the invariant probability with support on a periodic orbit of period two. This expression is based on the Jacobian of $ρ$ and two Radon-Nidodym derivatives.
ALMA reveals sequential high-mass star formation in the G9.62+0.19 complex
Creators: name: Liu, Tie
name: Lacy, John
name: Li, Pak Shing
name: Wang, Ke
name: Qin, Sheng-Li
name: Zhang, Qizhou
name: Kim, Kee-Tae
name: Garay, Guido
name: Wu, Yuefang
name: Mardones, Diego
name: Zhu, Qingfeng
name: Tatematsu, Ken'ichi
name: Hirota, Tomoya
name: Ren, Zhiyuan
name: Liu, Sheng-Yuan
name: Chen, Huei-Ru
name: Su, Yu-Nung
name: Li, Di
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Stellar feedback from high-mass stars (e.g., H{\sc ii} regions) can strongly influence the surrounding interstellar medium and regulate star formation. Our new ALMA observations reveal sequential high-mass star formation taking place within one sub-virial filamentary clump (the G9.62 clump) in the G9.62+0.19 complex. The 12 dense cores (MM 1-12) detected by ALMA are at very different evolutionary stages, from starless core phase to UC H{\sc ii} region phase. Three dense cores (MM6, MM7/G, MM8/F) are associated with outflows. The mass-velocity diagrams of outflows associated with MM7/G and MM8/F can be well fitted with broken power laws. The mass-velocity diagram of SiO outflow associated with MM8/F breaks much earlier than other outflow tracers (e.g., CO, SO, CS, HCN), suggesting that SiO traces newly shocked gas, while the other molecular lines (e.g., CO, SO, CS, HCN) mainly trace the ambient gas continuously entrained by outflow jets. Five cores (MM1, MM3, MM5, MM9, MM10) are massive starless core candidates whose masses are estimated to be larger than 25 M$_{\sun}$, assuming a dust temperature of $\leq$ 20 K. The shocks from the expanding H{\sc ii} regions ("B" \& "C") to the west may have great impact on the G9.62 clump through compressing it into a filament and inducing core collapse successively, leading to sequential star formation. Our findings suggest that stellar feedback from H{\sc ii} regions may enhance the star formation efficiency and suppress the low-mass star formation in adjacent pre-existing massive clumps.
description: Accepted to ApJ
Optical lattices as a tool to study defect-induced superfluidity
Creators: name: Astrakharchik, Grigory E.
name: Krutitsky, Konstantin V.
name: Lewenstein, Maciej
name: Mazzanti, Ferran
name: Boronat, Jordi
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We study the superfluid response, the energetic and structural properties of a one-dimensional ultracold Bose gas in an optical lattice of arbitrary strength. We use the Bose-Fermi mapping in the limit of infinitely large repulsive interaction and the diffusion Monte Carlo method in the case of finite interaction. For slightly incommensurate fillings we find a superfluid behavior which is discussed in terms of vacancies and interstitials. It is shown that both the excitation spectrum and static structure factor are different for the cases of microscopic and macroscopic fractions of defects. This system provides a extremely well-controlled model for studying defect-induced superfluidity.
description: 14 pages, 13 figures, published version
Applications of position-based coding to classical communication over quantum channels
Creators: name: Qi, Haoyu
name: Wang, Qingle
name: Wilde, Mark M.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: Information Theory (cs.IT)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Recently, a coding technique called position-based coding has been used to establish achievability statements for various kinds of classical communication protocols that use quantum channels. In the present paper, we apply this technique in the entanglement-assisted setting in order to establish lower bounds for error exponents, lower bounds on the second-order coding rate, and one-shot lower bounds. We also demonstrate that position-based coding can be a powerful tool for analyzing other communication settings. In particular, we reduce the quantum simultaneous decoding conjecture for entanglement-assisted or unassisted communication over a quantum multiple access channel to open questions in multiple quantum hypothesis testing. We then determine achievable rate regions for entanglement-assisted or unassisted classical communication over a quantum multiple-access channel, when using a particular quantum simultaneous decoder. The achievable rate regions given in this latter case are generally suboptimal, involving differences of Renyi-2 entropies and conditional quantum entropies.
description: v4: 44 pages, v4 includes a simpler proof for an upper bound on one-shot entanglement-assisted capacity, also found recently and independently in arXiv:1804.09644
Rotation curves of high-resolution LSB and SPARC galaxies with fuzzy and multistate (ultra-light boson) scalar field dark matter
Creators: name: Bernal, Tula
name: Fernández-Hernández, Lizbeth M.
name: Matos, Tonatiuh
name: Rodríguez-Meza, Mario A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Cold dark matter (CDM) has shown to be an excellent candidate for the dark matter (DM) of the Universe at large scales, however it presents some challenges at the galactic level. The scalar field dark matter (SFDM), also called fuzzy, wave, Bose-Einstein condensate or ultra-light axion DM, is identical to CDM at cosmological scales but different at the galactic ones. SFDM forms core halos, it has a natural cut-off in its matter power spectrum and it predicts well-formed galaxies at high redshifts. In this work we reproduce the rotation curves of high-resolution low surface brightness (LSB) and SPARC galaxies with two SFDM profiles: (1)~The soliton+NFW profile in the fuzzy DM (FDM) model, arising empirically from cosmological simulations of real, non-interacting scalar field (SF) at zero temperature, and (2)~the multistate SFDM (mSFDM) profile, an exact solution to the Einstein-Klein-Gordon equations for a real, self-interacting SF, with finite temperature into the SF potential, introducing several quantum states as a realistic model for a SFDM halo. From the fits with the soliton+NFW profile, we obtained for the boson mass $0.212< m_ψ/(10^{-23} \mathrm{eV}/c^2)<27.0$ and for the core radius $0.326< r_c/\mathrm{kpc}<8.96$. From the combined analysis with the LSB galaxies, we obtained $m_ψ= 0.554 \times10^{-23}\mathrm{eV}$, a result in tension with the severe cosmological constraints. Also, we show the analytical mSFDM model fits the observations as well as or better than the empirical soliton+NFW profile, and it reproduces naturally the wiggles present in some galaxies, being a theoretically motivated framework additional or alternative to the FDM profile.
description: 24 pages, 11 figures. Accepted for publication in MNRAS
Experimental Verification of the Universality of Magnetic-Field-Induced Bose-Einstein Condensation of Magnons
Creators: name: Shirasawa, Kazuki
name: Kurita, Nobuyuki
name: Tanaka, Hidekazu
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: CsFeBr$_3$ is an $S\,{=}\,1$ hexagonal antiferromagnet that has a singlet ground state owing to its large easy-plane single-ion anisotropy. The critical behavior of the magnetic-field-induced phase transition for a magnetic field parallel to the $c$ axis, which can be described by the Bose-Einstein condensation (BEC) of magnons under the $U(1)$ symmetry, was investigated via magnetization and specific heat measurements down to 0.1$\,$K. For the specific heat measurement, we have developed a method of effectively suppressing the torque acting on a sample with strong anisotropy that uses the spin dimer compound Ba$_2$CoSi$_2$O$_6$Cl$_2$ with large and anisotropic Van Vleck paramagnetism. The temperature dependence of the transition field $H_{\rm c}(T)$ was found to follow the power-law $H_{\rm c}(T)\,{-}\,H_{\rm c}\,{\propto}\,T^ϕ$ with a critical exponent of $ϕ\,{=}\,1.50\,{\pm}\,0.02$ and critical field of $H_{\rm c}\,{=}\,2.60$ T. This result verifies the universality of the three-dimensional BEC of magnons described by $ϕ_{\rm BEC}\,{=}\,3/2$.
description: 5 pages, 3 figures, to appear in Phys. Rev. B
A Quantum Algorithm for Finding Common Matches Between Databases with Reliable Behavior
Creators: name: El-Wazan, Khaled
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Given $κ$ databases of unstructured entries, we propose a quantum algorithm to find the common entries between those databases. The proposed algorithm requires $\mathcal{O}(κ\sqrt{N})$ queries to find the common entries, where $N$ is the number of records for each database. The proposed algorithm constructs an oracle to mark common entries, and then uses a variation of amplitude amplification technique with reliable behavior to increase the success probability of finding them.
description: 12 pages, 5 figures
A Phase Vocoder based on Nonstationary Gabor Frames
Creators: name: Ottosen, Emil Solsbæk
name: Dörfler, Monika
Publisher: name: arXiv
Year: 2016
Subjects: subject: Sound (cs.SD)
subject: FOS: Computer and information sciences

description: We propose a new algorithm for time stretching music signals based on the theory of nonstationary Gabor frames (NSGFs). The algorithm extends the techniques of the classical phase vocoder (PV) by incorporating adaptive time-frequency (TF) representations and adaptive phase locking. The adaptive TF representations imply good time resolution for the onsets of attack transients and good frequency resolution for the sinusoidal components. We estimate the phase values only at peak channels and the remaining phases are then locked to the values of the peaks in an adaptive manner. During attack transients we keep the stretch factor equal to one and we propose a new strategy for determining which channels are relevant for reinitializing the corresponding phase values. In contrast to previously published algorithms we use a non-uniform NSGF to obtain a low redundancy of the corresponding TF representation. We show that with just three times as many TF coefficients as signal samples, artifacts such as phasiness and transient smearing can be greatly reduced compared to the classical PV. The proposed algorithm is tested on both synthetic and real world signals and compared with state of the art algorithms in a reproducible manner.
description: 10 pages, 6 figures
title: Wie verdeutlicht sich Demokratielernen im Bürgerrat?
Creators: name: Hausberger, Franz-Josef
Year: 2023

description: Ein Bürgerrat setzt sich aus repräsentativ ausgewählten Teilnehmenden zusammen und unterliegt, wie jedes soziale Aggregat, einer bestimmten Strukturlogik. Die Masterthesis geht den verwobenen Fragen nach, welchen Ordnungsprinzipien die Interaktanten im Zuge der ihnen auferlegten Aufgabe, Lösungen zu den Themen fairer Wahlprozess und hohe Wahlbeteiligung zu erarbeiten, konversational folgen und welches Deutungsmuster hinsichtlich einer demokratischen Lerndisposition innerhalb der Vollzugswirklichkeit des Dialogs zum Vorschein kommt. Dafür wird zunächst mit Hilfe des Begriffs der „Reflexivität“ auf den Zusammenhang von sprachlichem Handeln (im Bürgerrat von einer „Teilgesellschaft“ praktiziert) und „der Gesellschaft“ allgemein verwiesen, um in weiterer Folge die Institution Bürgerrat demokratietheoretisch einzubetten. Anschließend wird anhand von drei Textsequenzen die „latente Sinnstruktur“ des Bürgerrates objektiviert und die demokratische Modalität bewertet. Es zeigt sich, dass eine teleologisch-essentialistische Reflexionsebene nicht verlassen wird und somit kein deliberatives bzw. transformatives Demokratielernen vorliegt.
description: A citizens' council is made up of representatively selected participants and, like any social aggregate, is subject to a certain structural logic. The Master‘s Thesis investigates the interwoven question of which organizing principles the interactants follow in conversation in the course of the task imposed on them to develop solutions on the subject of a fair election process and high election turnout, and which interpretation pattern emerges with regard to a democratic learning disposition within the ongoing accomplishment of the dialogue. First of all, the concept of "reflexivity" is used to refer to the connection between linguistic action (practiced by a "sub-society" in the citizens' council) and "society" in general, in order to subsequently embed the institution of the citizens' council in democratic theory. Then, based on three text sequences, the "latent structure of meaning" of the citizens' council is objectified and the democratic modality is evaluated. It shows that a teleological-essentialistic level of reflection is not left and thus there is no deliberative or transformative learning of democracy.
The part and the whole: voids, supervoids, and their ISW imprint
Creators: name: Kovács, András
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The integrated Sachs-Wolfe imprint of extreme structures in the cosmic web probes the dynamical nature of dark energy. Looking through typical cosmic voids, no anomalous signal has been reported. On the contrary, supervoids, associated with large-scale fluctuations in the gravitational potential, have shown potentially disturbing excess signals. In this study, we used the Jubilee ISW simulation to demonstrate how the stacked signal depends on the void definition. We found that large underdensities, with at least $\approx5$ merged sub-voids, show a peculiar ISW imprint shape with central cold spots and surrounding hot rings, offering a natural way to define supervoids in the cosmic web. We then inspected the real-world BOSS DR12 data using the simulated imprints as templates. The imprinted profile of BOSS supervoids appears to be more compact than in simulations, requiring an extra $α\approx 0.7$ re-scaling of filter sizes. The data reveals an excess ISW-like signal with $A_{\rm ISW}\approx9$ amplitude at the $\approx2.5σ$ significance level, unlike previous studies that used isolated voids and reported good consistency with $A_{\rm ISW}=1$. The tension with the Jubilee-based $Λ$CDM predictions is $\sim 2σ$, in consistency with independent analyses of supervoids in Dark Energy Survey data. We show that such a very large enhancement of the $A_{\rm ISW}$ parameter hints at a possible causal relation between the CMB Cold Spot and the Eridanus supervoid. The origin of these findings remains unclear.
description: 16 pages, 10 figures. Version accepted by MNRAS
Surface States in Holographic Weyl Semimetals
Creators: name: Ammon, Martin
name: Heinrich, Markus
name: Jiménez-Alba, Amadeo
name: Moeckel, Sebastian
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the surface states of a strongly coupled Weyl semimetal within holography. By explicit numerical computation of an inhomogeneous holographic Weyl semimetal we observe the appearance of an electric current restricted to the surface in presence of electric chemical potential. The total current is universal in the sense that it only depends on the topology of the phases showing that the bulk-boundary correspondence holds even at strong coupling. The implications of this result are subtle and may shed some light on anomalous transport at weak coupling.
description: 7 pages, 6 figures. v2: citation added
Existence and approximation of fixed points of vicinal mappings in geodesic spaces
Creators: name: Kohsaka, Fumiaki
Publisher: name: arXiv
Year: 2017
Subjects: subject: Functional Analysis (math.FA)
subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 47H10, 47J05, 52A41, 90C25

description: We propose the concepts of vicinal mappings and firmly vicinal mappings in metric spaces. We obtain fixed point and convergence theorems for these mappings in complete geodesic spaces with curvature bounded above by one and apply our results to convex optimization in such spaces.
description: 14 pages; some minor corrections were made. arXiv admin note: text overlap with arXiv:1704.01360